PRE2016 3 Groep5: Difference between revisions

From Control Systems Technology Group
Jump to navigation Jump to search
No edit summary
 
(57 intermediate revisions by 5 users not shown)
Line 1: Line 1:
== Group Members ==
= Group Members =


{| class="wikitable" style="width: 300px"
{| class="wikitable" style="width: 300px"
Line 25: Line 25:
|}
|}


== Presentation ==
=Introduction=
Since 1945 plastic is inseparable from our society, where it brought us great fortune and great use. It is used to carry drinks, package foods, toys, etc. Whereas it has a good side that helps humanity, it also has its downsides. A lot of people throw their garbage, of which most is plastic, very easily on the ground and in rivers. This means the mainland and the oceans get polluted, instead of the plastic being recycled, when it is thrown away. On the mainland, there are a lot of organizations, which focus on preserving the mainland’s environment. For example by sending people to collect waste next to roads and beaches. A number of organizations in the seas and oceans are, however, greatly outnumbered. While the organizations on the mainland can hardly keep the pollution at a steady level, the pollution in the seas and oceans has risen exponentially for several years already. The plastic in the ocean decomposes gradually which results in a highly soiled sea which is more difficult to clean up. Even when the plastic decomposes into small parts, it affects and influences the marine ecosystem as a whole. A fish cannot tell food and plastic apart and slowly gets poisoned and killed by the toxic plastic in its stomach. The same happens to many birds that get their food out of the water.


Current situation:
A number of organizations in the seas and oceans are, however, greatly outnumbered. While the organizations on the mainland can hardly keep the pollution at a steady level, the pollution in the seas and oceans has risen exponentially for several years already. The plastics in the ocean decompose gradually which results in a highly soiled sea which is more difficult to clean up. The small parts of plastics influence the marine ecosystem as a whole. Fish cannot tell food and plastic apart and slowly gets poisoned and killed by the toxic plastic in its stomach. The same happens to many birds that get their food out of the water and even humans can be affected by this. If a fish gets poisoned and a human will eats that fish, then the human will also be affected by the effects.


For years the ocean has accumulated a lot of plastic, trapping it in the sea’s current. This plastic soup has become a danger to the oceans ecosystems and it’s wildlife. It has become a danger for animals because birds can get stuck in the plastic, birds and fish eat the plastic. When it decomposes the fish get contaminated with the various toxic residues. This contaminates the whole food chain as birds, larger fish and humans eat the contaminated marine wildlife. Furthermore some species can get dragged along with the floating garbage and negatively influence new ecosystems in which they get introduced.  
The plastic that gets in the sea, gathers in so-called ‘gyres’. These are huge area’s to which the plastic floats due to the current. It slowly floats in circles in the same area. There are 5 huge gyres around the world. See Figure 1 below.
 
Concept idea:
 
We want to design an autonomous robot to help clean the ocean’s garbage. In order to reach this goal the robot has to have certain functions: First of it has to perceive it’s environment and the plastic contaminating it. It has to know or have the ability to get the plastic out of the water, this includes the waves and current of the ocean it’s cleaning. Once it has retrieved the plastic it has to compress it, store it in safe space aboard the robot and empty the compartment at a designated location when full.
 
Users:
 
The technology we want to design will influence the users future by investing in a better environment by cleaning it, preserving the current ecosystems contaminated by the plastic and lastly it helps preventing people from eating contaminated food as mentioned earlier.
 
Society:
 
By using the technology society will improve the future by stopping the influence plastic has on the environment. Cleaning the ocean is a start to creating a better society. And lastly it will preserve the current marine wildlife.
 
Enterprise:
 
This technology can be used by the government to clean up the ocean and may be sponsored by foundations as Greenpeace and the WWF.


Challenges:
[[File:gyres.jpg]]
          Figure 1, the 5 gyres in the world


The biggest challenges in creating a suitable cleaning agent are that it needs to know where it is and where it needs to go. It needs to distinguish plastic content from any other products or wildlife it’s trying to safe, otherwise it would further damage the ecosystem. In order to do the two things mentioned above it needs to take into account the currents and waves so it doesn’t try to clean sections it has already cleaned and because of the current these locations will changes constantly. A big part of the problem is the fact that it needs to be optimized in order to be efficient in cleaning. If one has more than one robot, they need to be able to “communicate” to prevent them from doing each other’s work, also this needs separate optimization because of the fact that we’re dealing with multiple entities. And lastly the technology needs to be sustainable and durable itself, because it wouldn’t have a use if it were to pollute the environment more than it is cleaning it.
Currently, there is a project that is cleaning up these gyres. They put down a giant net in the gyres and let the current of the gyres pour the plastic in the gyres. This way all the plastic gets pushed into the net and collected in one place. However cleaning up the gyres alone is not enough. The plastic that is in the gyres came from somewhere and the gyres are still growing every day. That’s why it is also important to prevent the gyres from getting bigger, by cleaning up the plastic closer to its source.


==History and background of the plastic Ocean==
The thing that has to be accomplished, is preventing the gyre from becoming bigger. Prevention starts with looking at the coast of The Netherlands. The goal that is set for this project is to try to let no plastic/garbage pass through the coast of The Netherlands. The current of the North Sea along The Netherlands is from the bottom to the top or the other way around, which depends on the tides. This is very convenient for setting up places for agents. When a plastic/garbage unit is not cleaned on the beginning of the flow, then it will be cleaned up later by another agent that is in another place at the coast. Also, a lot of plastic comes from the beaches and the harbors. It is, therefore, important to stop the flow of plastic/garbage as close as possible to the source. This is the reason why the agents are placed along the coast of The Netherlands. This will mean that the plastic/garbage will be cleaned up before it comes in the gyres.<ref  name=intro1>http://www.plasticsoupfoundation.org/feiten/gevolgen-voor-het-milieu/</ref> <ref name=intro2> http://www.plasticsoupfoundation.org/feiten/gezondheidseffecten/</ref> <ref name=intro3> http://www.icgrevelingen.nl/blog/2016/01/14/cleanriverproject/</ref> <ref name=intro4> https://www.theoceancleanup.com/</ref> <ref name=intro5> http://www.tedxdelft.nl/2012/10/tedxdelft-first-performer-boyan-slat/</ref> <ref name=intro6> https://plasticsoepsite.wordpress.com/onstaan-plasticsoep/</ref> <ref name=intro7> https://www.theoceancleanup.com/technology/</ref> <ref name=intro8> http://www.wur.nl/nl/Dossiers/dossier/Plastic-afval-in-zee.htm</ref>


The dawn of plastics was in America at the year 1850. However only since 1945, it was inseparable from our society, where it brought us great fortune and great use. Plastics helped people carry drinks, package foods and could be used as a toy for the kids. Present-day plastics are still used in large quantities, helping us in daily life, however the use of plastics also has its dark side.
=Current situation=
While plastic is recyclable most of the time, it is not sure whether a plastic bottle for instance gets recycled at all. People throw their garbage, which is mainly plastic, far too easily on the ground and in the rivers. Polluting the mainland and the oceans, or the environment as a whole, .
In order to tackle the problem, a good overview of the situation need to been set. This is done by writing down all the questions about the garbage problem in the North sea and then the searching for answers started. The strategy was as follows; first search for the answer on internet to get a basic intuition and then contact several organizations asking them all the same questions and combine all this information into one final answer.  
Where on the mainland there are a lot of organizations, which focus on preserving the mainland’s environment. For example by sending people who collect plastics and other waste next to roads and in forests. The amount of organizations in the seas and oceans are however, greatly outnumbered. While the organizations on the mainland can hardly keep the pollution at a steady level, the pollution in the seas and oceans has risen exponentially for several years already.  
The plastics in the ocean decompose gradually which results in a highly soiled sea which is more difficult to clean up. The small parts of plastics influence the marine ecosystem as a whole. Fish cannot tell food and plastic apart and slowly gets poisoned and killed by the toxic plastic in its stomach. The same happens to many birds that gets their food out of the water, for example the albatross displayed below.


'''Image albatross'''
The main sources that were used are either reports or the organizations that were contacted. The following are the reports used:
*Wat spoelt er aan op het strand – Stichting De Noordzee
*Mariene Strategie voor het Nederlandse deel van de Noordzee 2012-2020 – Rijksoverheid
*Jaarverslag 2015 – Stichting De Noordzee
*Guideline for Monitoring Marine Litter on the Beaches in the OSPAR Martime Area – OSPAR commission
*The vertical distribution of buoyant plastics at sea: an observational study in the North Atlantic Gyre – J. Reisser, B. Slat, K. Noble, K. du Plessis, M. Epp, M. Proietti, J. de Sonneville, T. Becker and C. Pattiaratchi


These plastics not only have an influence on the life of fish and birds, but it also has a great influence on mankind. Polluting our drinking water, which is more difficult to purify, and polluting the food chain where we are on top, so that means that we eat all the toxins that animals below us eat.
The following organizations were contacted:
Therefore it is time that mankind focuses on cleaning up the ocean more effectively. In this project we want to create an AI which can help in the dusk of the plastic ocean. In that way the marine ecosystem can be preserved and mankind’s skin can be saved.
*CBS
*Rijkswaterstaat
*Kustwacht
*Clean up
*Greenpeace
*Stichting de Noordzee


==Plan of execution==
Of course, not all organizations were as helpful, but there was enough response to get a complete answer to all the questions there were. Here are the questions that were asked, followed by the answer in italic.  
In this part of the chapter we’re going to define a plan of execution for the chosen project challenge. This will include a first explanation of the things we need to execute to reach our goal. Then there will be a definition of tasks, timetable, deliverables, milestones, Gant chart.


- First, we want to analyze what the current situation is and at what scale we can clean up the plastic polluted ocean. After that we want to analyze what it takes to clean up a part of ocean.
*Is the problem significant enough for organizations like the government to invest money in?


- Contact companies to get more information about demand/the current situation.
''There are several organizations searching for solutions for this problem, which it is significant enough to be solved. Not just the pollution issue in itself is a problem for these organizations, but also the health issues when the garbage breaks down and ends up in the food chain. The government is the biggest investor since it is a societal matter and it is hard for a profit-seeking company to make money off. So if we can show the government that our project is the solution to this problem, our project could be worth investing in.''


- Then we will look at what kind of robot will be fit for gathering garbage. The robot has to be designed.


*Which kinds of garbage objects are most common in the North sea?


- After that the strategy it will use will be made. It is ofcourse difficult to decide how to place them.
''There are multiple organizations (Rijkswaterstaat, Stichting Noordzee en NIOZ) that monitor the garbage on the beaches and in the North sea. With this data a list was composed, summing up the top 10 most found garbage objects in and around the sea.''


- After the strategy is determined, a model in netlogo will be made, to see if the strategy works.
**''Ropes and nets''
**''Plastic pieces''
**''Plastic bags ''
**''lids''
**''Candy wrappers''
**''Balloons ''
**''Plastic bottles''
**''Wood''
**''Plastic food packaging''
**''Industrial plastic contents''


- With that information we can draw a conclusion of how it will work and if it will work.
*Who are responsible for the garbage in the North sea and where are they located at the coastline?


==Current Situation==
''More than half of the waste comes from the maritime sector. So logically the major port cities are geographical hot-spots with regard to the dumping of plastic waste in the North sea. Other pollution comes mainly from the people visiting the beaches, so crowded beaches are also potential hot-spots. Also, the rivers are highly polluted which makes the places where the rivers goes into the ocean as a dumping hot-spot''
Here, we want to analyze the current situation to determine at what scale we can clean up the plastic polluted ocean. The situation is already sketched in the introduction, however in this part it will be clarified more thoroughly.
Recently, the accumulation and possible impact of micro-plastic particles in the ocean have been recognized as an emerging environmental issue. To reduce the quantity of plastic entering the ocean, existing management instruments need to be made more effective and all aspects of waste treatment and disposal need to be improved. Media attention has focused on reports of the relatively high incidence of plastic debris in areas of the ocean referred to as ‘convergence zones’ or ‘ocean gyres’. This has given rise to the widespread use of terms like ’plastic soup’, ‘garbage patch’ and ‘ocean landfill’. Such terms are rather misleading in that much of the plastic debris in the ocean consists of fragments that are very small in size while the areas where they are floating are not, for example, distinguishable on satellite images. Nevertheless, publicity for plastic debris in the ocean has helped to raise public and political awareness of the global scale of the plastic debris problem, together with the larger issue of marine litter.
It is difficult to quantify the amounts and sources of plastic and other types of debris entering the ocean. Land-based sources include poorly managed landfills, river transport, untreated sewage and storm water discharges, industrial and manufacturing facilities within adequate controls, wind-blown debris, recreational use of coastal areas, and tourist activities(Barnes et al. 2009). These sources are thought to dominate the overall supply of marine debris, but there are important regional variations. For example, shipping and fisheries are significant contributors in the East Asian Seas region and the southern North Sea (UNEP/COBSEA 2009, Galgani et al. 2010). In general, more litter is found closer to population centers, including a greater proportion of consumer


'''2 images'''
*Are there hot-spots were the garbage gathers (under influence of the current), are these hot-spots on the coastline and/or in the sea? If they exist, where can they be found?


plastic items, such as bottles, shopping bags and personal hygiene products(Ocean Conservancy 2010).
''Generally speaking, the plastic gets smaller in terms of size the further one distances itself from the coast. Our focus is mainly on the larger pieces of plastic, so in combination with the previous question, the hot-spots can be recorded around the mouths of rivers and harbors and along the coastline crowded beaches.''
As already stated, the ocean is littered with a lot of plastic, almost 80 percent of the plastic that can be found in the oceans originated from the shores. The plastic is carried along by the currents that exist in the ocean. These plastics sometimes run ashore where they can be easily gathered by humans with a garbage bag, however often those plastics stay in the ocean and drift all over the world. Therefore we wanted to look at the idea of collecting plastics inside a gyre, because gyres have a circular current which means that these plastic will float in circles for a long time and therefore can be more easily detected then plastics which stay outside of a gyre.
There are 5 huge gyres in the total stretch of ocean. These gyres are given in the picture below.


'''image gyres'''
*What is the order of magnitude of the garbage that is in the North sea, do you have exact numbers?


These five gyres are evaluated to determine whether it is realistic to clean up a gyre at all. They are evaluated by mentioning the following aspects:
''Regarding soil pollution of the North Sea, we are talking about 110 pieces of plastic per square kilometer in the North sea. Pollution along the coastline is 380 pieces per debris 100 meters beach.''
- Size gyre
- Flow speed
- Plastic Supply
- The amount of plastic
- Size patch
The results of these 5 gyres are given in a table in the appendix.


==Existing organizations==
*At what depth is can the garbage be found?
'''Facts'''


- More litter is found closer to population centers, including a greater proportion of consumer plastic items such as bottles, shopping bags and personal hygiene products (Ocean Conservancy 2010).  
''The greatest concentration of debris is around or on the surface. There has been measured up to a depth of 5 meters, and from this, it was found that 80% of the waste was in the first 2-3 meters. Which will be further explained in the chapter garbage distribution in the Appendix.''


- In general, potential chemical effects are likely to increase with a reduction in the size of plastic particles while physical effects, such as the entanglement of seals and other animals in drift plastic, increase with the size and complexity of the debris.
*Are you familiar with a comparable project like ours, if so could u give us some information about the projects?
   
   
- Costs associated with the presence of plastic and other types of marine debris are often borne by those affected rather than those responsible for the problem (ten Brink et al. 2009, Mouat et al. 2010). The most obvious impacts are economic, such as loss of fishing opportunities due to time spent cleaning litter from nets and propellers, and blocked water intakes. Marine litter costs the Scottish fishing industry an average of between US$15 million and US$17 million per year, the equivalent of 5 per cent of the total revenue of affected fisheries. Marine litter is also a significant ongoing navigational hazard for vessels, as reflected in the increasing number of coastguard rescues to vessels with fouled propellers in Norway and the United Kingdom: there were 286 such rescues in British waters in 2008, at a cost of up to US$2.8 million (Mouat et al. 2010).  
''A similar project is the ocean clean up. The idea is to be achieved on a large scale waste in the North Pacific gyre using two long arms. However, this project is on a much larger scale with a higher concentration of waste per km ^ 2 so not really applicable to our problem.


- Cleanups of beaches and waterways can be expensive. In the Netherlands and Belgium, approximately US$13.65 million per year is spent on removing beach litter.  
Another project was undertaken by water network. It has created an autonomous agent, named Nautonomous, which navigates through the water and gathers waste on a treadmill, this agent can be seen in Figure 2.<ref name=Nautonomous>https://www.youtube.com/watch?v=BYXlv8fgj80&feature=youtu.be</ref> <ref name=Nautonomous2>https://www.waternet.nl/blog/de-nautonomous-automatisch-drijfvuil-vissen/</ref>


- Other considerations include ‘aesthetic intangible costs’. Litter can affect the public’s perception of the quality of the surrounding environment. This, in turn, can lead to loss of income by local communities engaged in tourism, and in some cases by national economies dependent on tourism and associated economic activities (ten Brink et al. 2009, Mouat et al. 2010).
[[File:autonomous.jpg]]
      Figure 2, Nautonomous


'''International conventions and tackling the problem'''
Another similar project was set up by the recycled Island Foundation. they make a sort of trial and place it on the coast of Rotterdam in strategic places and capture that way plastic.'' <ref name=foundation>http://www.recycledisland.com/</ref>


Monitoring, surveillance and research focusing on plastic and other types of marine litter have increased in recent years. Nevertheless, a comprehensive set of environmental indicators for use in assessments has been lacking, as have related social and economic indicators. These types of indicators could include trends in coastal population increase and urbanization, plastics production, fractions of waste recycled, tourism revenue, waste disposal methods, shipping tonnage and fishing activities. Indicators also provide a means to measure the effectiveness of mitigation measures, such as improved waste management and the introduction of economic measures. At the regional level, the European Commission is developing methods to assess the extent of the marine litter problem. This activity is taking place under the comprehensive Marine Strategy Framework Directive (EU 2008, Galgani et al. 2010), with indicators being produced to monitor progress towards achieving ‘good environmental status’ by 2020.
=Environmental aspects=
==Work space of agents==
In the North sea, there are some areas that cannot be traversed or are very busy with traffic. Along the coast of The Netherlands, there are areas that are protected by law. This is however mostly because of fisherman. That means that the agent will not be restricted, when it comes to those areas since it does not fish or harvest any other natural products. The problem that should be taken into account is the ship’s navigational routes. There are areas where there is a lot of boat traffic, especially at the ports. Along the coast, this is not an issue. (Appendix Environment)<ref name=beschermd>https://www.noordzeeloket.nl/functies-en-gebruik/natuur_en_biodiversiteit/</ref><ref name=scheepvaart>https://www.noordzeeloket.nl/functies-en-gebruik/scheepvaart/</ref><ref name=visserij>https://www.noordzeeloket.nl/images/Bodemberoerende%20visserij%20op%20de%20Noordzee%20-%20Huidige%20situatie,%20recente%20ontwikkelingen%20en%20toekomstscenario%E2%80%99s_4125.pdf/</ref><ref name=protected>http://www.rwsnatura2000.nl/default.aspx/</ref><ref name=Noordzee>https://www.noordzee.nl/</ref>


'''Image'''
==Waves and wind issues==
When an agent is at sea it is not safe for the agent when there are high waves. It could break because it gets destroyed by a big wave. Looking at how waves are created, it is found that the wind is playing a big part in it. The harder and longer the wind blows, the bigger the waves will be. It is, therefore, hard to say when the agent should go back at a certain wind speed. However, some things can be determined, like at what wind speed it is dangerous and how big waves will get at a certain wind speed. For small boats, for example, canoes, it is recommended not to go on open sea if the wind speed is bigger or equal to 6Bft. Which means a medium wind. In table 2 is shown how high the waves will get at a certain wind speed.


Short summary: two major conventions specifically address marine litter in the ocean: MARPOL and London convention with its protocol (London Protocol). Three categories:
1. shipping pollution(MARPOL);
2. reception facilities at ports and terminals for the reception of garbage;
3. control of dumping of wastes at sea that have been generated on land (London convention).


'''Ocean clean up'''
      Table 2, Influence wind on wave height
[[File:Wind.jpg]]


TECHNOLOGY
When the waves get higher than 1,7-2 meters it is too high for the agents. Before the agents will go on the water, the wind speed is measured. Also, while they are working the wind speed should be updated. This way the height of the current waves can be determined. When this calculation is done a decision can be made whether the agents should go to work or not. Also when they are working and the wind speed gets too high, it can be determined after how much time they should be called back to the coast. <ref name=wind1>http://www.wadkanovaren.nl/hetwadfysiek.html</ref> <ref name=wind2>http://www.wadkanovaren.nl/veiligheid.html</ref>


Cleanup using conventional methods - vessels and nets - would take thousands of years and tens of billions of dollars to complete. The ocean clean up’s passive system could remove about half the Great Pacific Garbage Patch in 10 years, at a fraction of the cost.
==Animals==
Why move through the ocean, if the ocean can move through you?
===Birds===
Ocean garbage patches are vast but dispersed. By acting like an artificial coastline, the ocean clean up initiative passively concentrates the plastic by orders of magnitude, 100% powered by natural ocean currents. Their passive cleanup units are designed to capture virtually any type of debris. Models show that by utilizing vast rotational ocean currents, cleanup systems with a combined span of 100km can harvest almost half the Great Pacific Garbage Patch in 10 years.
An often overlooked problem are birds sitting on the boat. This is not convenient since a part of the boat might break or can get dirty. This problem is not hard to solve because there are some small tips and tricks that can prevent them from getting on a boat. For example, getting some netting and putting it above places they can land. Putting a fake crow on the boat or a string with cd’s attached to it will most likely scare the most of those birds away.


Instead of using nets, The Ocean Cleanup uses solid screens which catches the floating plastic, but allows sea life to pass underneath the barrier with the current. The Ocean Cleanup Array is designed to be as flexible as possible. This allows it to move along with the waves, which is key in ensuring the structure will be able to survive the most extreme conditions.
===Fish===
Thanks to the orientation of the barriers moored to the seabed, plastic will slowly be pushed towards the center of the array, becoming even more concentrated.
There are a lot of fish in the sea, which poses a problem. It would not be the intention to accidentally catch fish instead of garbage on the way. However, it is assumed, that the agents will make a certain noise and they won’t go too fast. This means the fish have plenty of time to see it coming and have enough time to get away.
A central collection point extracts and buffers the debris, before being shipped to land. By recycling the debris and selling the semi-finished product directly to B2C companies, they aim to eventually make the operation self-sustainable.
The modular array approach can be applied on any scale; from small-scale systems to intercept plastic near land, to multi-kilometer installations to clean up ocean garbage patches.


30 DECEMBER 2015 FIRST CLEANUP BARRIER TEST TO BE DEPLOYED IN DUTCH WATERS


The Ocean Cleanup will be deploying a 100 meter-long barrier segment in the second quarter of 2016 in the North Sea, 23 km off the coast of The Netherlands The main objective of the North Sea test is to monitor the effects of real-life sea conditions, with a focus on waves and currents. The motions of the barrier and the loads on the system will be monitored by cameras and sensors. The floating barriers are regarded as one of the most critical elements of the concept, since they are responsible for capturing and concentrating the plastic debris. The North Sea test will be helping to ensure the effectiveness and durability once the large-scale system will be deployed in the Great Pacific Garbage Patch in 2020.
=Solution=
Sponsors/Partners
==Different concepts==
their partners can be found on the following page
During the project, a few different designs and possible solutions were created. These vary on a wide spectrum. Following are some of the concepts created.
https://www.theoceancleanup.com/partners/


OTHER INITIATIVES FOR OCEAN CLEANUP
===The retrieval arm===
The first design was to construct a boat with a number of arms on it to pick up each piece of garbage separately. While this would be a good option since it could grab pieces that are two to three meters deep. The programming of an arm is a whole project in and of itself. also, this design would make the boat too unstable when picking the garbage out of the water due to a large amount of mass moved.
Nets on either side
The second design was to make a boat with nets on either side that would rotate whenever a piece of garbage is caught. However, this could also, catch fish which is unwanted. Also, the design is not energy efficient because of the fact that it needs to move the nets in a rotational way which would consume a lot of energy.


The Global Programme of Action for the Protection of the Marine Environment from Land-based Activities
===Conveyor belts===
The third design was to make a boat with conveyor belts to guide the garbage to a center flow area where they would be scooped up by another conveyor into a compartment. This design also was not very energy efficient. A lot of energy would be lost in moving the conveyors and the non-hydrodynamic design. It also could only pick up garbage that floats on the surface of the water.


The Global Programme of Action (GPA) for the Protection of the Marine Environment from Land-based Activities, whose Secretariat is provided by UNEP, is the only global initiative that directly addresses the link between watersheds, coastal waters and the open ocean (UNEP/GPA 2011). It provides a mechanism for the development and implementation of initiatives to tackle trans-boundary issues. Plastic and other types of marine debris are such an issue. In collaboration with the Food and Agriculture Organization of the United Nations(FAO), a comprehensive report on abandoned, lost or otherwise discarded fishing gear has been published (Macfadyen et al. 2009).
===Ramp to catch garbage===
The final design was to make a boat with a ramp in the water. This way the garbage drifting two to three meters deep in the water can be pulled to the surface where they will be transported via conveyor belts on either side of the boat into a compartment for storage. This design will generate a lot of downwards force due to the giant ramp in the water, this can, however, be prevented by putting a floater or engine in the front to compensate for the downwards force.
Regional initiatives


The Global Initiative on Marine Litter, a co-operative activity of UNEP/GPA and the UNEP Regional Seas Programme (UNEP/RSP), has organized and implemented numerous regional marine litter activities.
==Requirements, preferences and constraints==
The 18 Regional Seas Conventions and Action Plans could serve as platforms for developing common regional strategies and promoting synergies, mainly at the national level, to prevent, reduce and remove marine litter (UNEP 2009b)
To make sure a good design is made there is a large list of RPCs constructed. These are split up into the following categories to make it easy to read:


National and local initiatives
Dimensions:
*The boat needs to be 2 by 3 by 3 meters. This is so that the boat can still hold a lot of garbage. It also makes sure the boat is stable and it provides a large frontal area to pick up garbage.
*The compartment needs to be 1.5 by 2 by 2 meters, this way it can carry a lot of garbage without having to be emptied.
*The compartment needs to be separable in order to decrease downtime when emptying.
*The clips holding the compartment in place need to be easily removable for easy separation when emptying.
*The vehicle needs to have two floaters on each side (0.25 by 2 by 2.5 meters) in order to keep the boat floating in the water. Via Archimedes’ law, this means that the floaters will stay in the water for 80 percent with a full compartment.
*The boat needs one ball-shaped floater (radius 0.6 meters) to compensate for downwards drag when moving through the water.
*Space needs to be available for the conveyor belts on either side of the boat. These are needed to pull up the garbage once it is out of the water and transfer them to the compartment. This space would equate to 0.25 by 1 by 0.5 meters.
*There must be a guiding slide to transfer the garbage pulled up by the conveyors. The space would equate to 0.25 by 1 by 0.2 meters.


Ways to better understand and ultimately reduce the flow of plastic debris to the ocean are being sought through a range of national and local initiatives. For example, in the United States improved monitoring and assessment methods have been developed to identify and quantify the amounts and composition of marine litter. This initiative is coordinated by the National Oceanic and Atmospheric Administration (NOAA) and its partners. In the United Kingdom, the Waste and Resources Action Programme (WRAP) encourages businesses to reduce waste, increase recycling and decrease reliance on landfill (WRAP 2011). To help raise awareness, UNEP and NOAA co-hosted the 5th International Marine Debris Conference in March 2011 (IMDC 2011).
Material:
*The boat and the compartment are both made of polyester. This material is used in the construction of sailboats and is both strong and light.
*The floaters need to be made of poly-ether since it is the most used material for floaters in general.
*The whole vehicle and all of its parts need to be waterproof to prevent it from sinking. This can be done by using a coating over the polyester. According to the sources used this holds for about 25 years. <ref name=coat1> http://www.bootschilderen.nl/polyester/</ref> <ref name=coat2>https://polyestershoppen.nl/polyester/topcoat-transparant-66.html</ref>


Industry initiatives
Transferring:
*The vehicle needs to have a motor to move forward. In this project we have chosen for a ring motor, this motor should be strong enough for small boats up to 8 meters and therefore should be sufficient for our agent. <ref name=ring>http://www.destilleboot.nl/torque-jet-voor-g2/517/p111/c108/default.html</ref>
*It needs to have a fin located in the water to steer.
*It needs to have a large enough battery in order to fill its compartment and return to a charging station.The battery life should be at least 12 hours, however, to determine the exact battery life the size of the agent, the speed of the agent, the engine  distribution, the conveyor belts and the fin has to be looked at in more detail.


- The Fishing for Litter campaign is an example of a low cost voluntary activity. Developed through the Local Authorities International Environmental Organisation, it encourages fishers based around the North Sea to collect and bring to port any litter retrieved in their nets (KIMO 2011).  
Sensors:
*The vehicle needs to have a laser sensor in order to check if its compartment is full and needs to emptied. This laser gives the "full" signal when its trajectory is interrupted. However, this means that when the plastic is tossed into the container, it gives that signal. Therefore there need to be some kind of counter, which makes sure the signal gets send if and only if a certain time is past.
*It needs a GPS system to locate its position and to make it back to the nearest pickup point when a storm is inbound.
*The agent needs an inertial measurement unit in order to make sure it is still on the right path and the right speed when picking up garbage.<ref name=IMU>https://en.wikipedia.org/wiki/Inertial_measurement_unit#frbanner3 </ref>
*It needs to have an internet connection to check the weather for conditions in which the agent should not be on the water and to communicate with the control station if there is a part that has broken down or the agent needs to be called back to a pickup point in event of an emergency situation.


- Regional Marine Environment Protection Associations (MEPAs) have been established by the shipping sector to preserve the marine environment through educating those in the sector, port communities and children. (HELMEPA 2011) The MEPAs’ commitment ‘To Save the Seas’ includes voluntary cooperation to protect the marine environment from pollution, awareness and educational activities, promotion of health and safety standards, and enhancement of quality standards and professional competence throughout the organization’s membership (INTERMEPA 2011).
Life-cycle:
*The agent needs to keep working for 25 years, to minimize costs and to make sure it can keep cleaning the ocean, which unfortunately is never finished.


- The American and British plastics industries have implemented Operation Clean Sweep to reduce losses of resin pellets to the environment, particularly during their transport and shipment. Motivated by the need to comply with legislation, but also sound economics and good environmental stewardship, Operation Clean Sweep is contributing to the reduction of plastic pellets found in marine debris (Operation Clean Sweep 2011).
==strategy==


NGO Initiatives
For the agents to gather plastics as efficiently as possible a gathering strategy has to be made. To cover the whole area, a strategy in which the agents move vertically would be a logical approach. When this strategy is used, it seems that almost all of the plastic on top of the surface of the water will be gathered. However, due to the fact that most of the plastics in the North sea are found at a depth of 1-3 meters, this strategy will not be sufficient enough. Therefore a new strategy has to be considered. 


- The 5 Gyres initiative, which is currently investigating the distribution of micro-plastics and POPs in each of the five main ocean gyres in conjunction with Pangea Expeditions and the UN Safe Planet Campaign  (5 Gyres 2011).
To gather the plastic that is 1-3 meters deep in the water, 2 slides are designed in front of the agent. These slides are 1-3 meters deep and push the plastics to the surface of the water. To stimulate this upwards thrust, the strategy will be adapted to the figure below:


- Using equipment loaned to them, citizen scientists collect samples of plastic debris during their own sailing voyages and report their findings to the Algalita Foundation (Travel Trawl 2011).


- Project Kaisei is testing ways to remove some of the plastic in the ocean using low energy catch methods. Further studies are designed to determine types of remediation or recycling that could be applied to collected plastic material, including derelict fishing nets, so that there will be some potential for economic value creation to subsidize cleanup efforts (Project Kaisei 2011).
[[File:strategy.jpg]]
      Figure 3, Strategy


- The annual International Coastal Cleanup organized by the Ocean Conservancy is the world’s largest volunteer effort to collect information on the amounts and types of marine debris. In 2009, 498818 volunteers from 108 countries and locations collected 3357 tonnes of debris from over 6000 sites (Ocean Conservancy 2010). Plastic bags, the second most common item removed, have much greater potential impact than the number one item (cigarettes/cigarette filters).
In this strategy, the agent will navigate in the opposite direction of the current of the water. In this way, the plastics will collide to the slides and will be pushed due to the cooperation of the current and the speed of the agent. The best way to stimulate the thrust is to navigate the agents horizontally, parallel to the coast. However when the total area has to be covered there will be a lot of agents needed to gather all the plastics, therefore the strategy in the figure is the final strategy.
In this strategy, the following are presumed. The area which the agents will clean has a width of Y meters and a height of X meter. When tides shift, the current reverse direction. The tides shift every six hours <ref name=locations>http://www.ebvloedgetijde.nl/</ref>. Furthermore, the average speed of the current is equal to 1.15 meters per second. According to the RPC’s the agents need to navigate with a speed of at least 3 meters per seconds, this means that in 6 hours an agent can travel a total amount of 64800 meters. To estimate the size of the area it will be presumed that the agent finishes n spikes at the total width of Y meters. De X and  Y can be calculated by the following Equation 1:


- Clean Up the World is an initiative started by an individual motivated to take action by the amount of plastic debris he discovered when sailing in the open ocean. Since 1993, it has developed into an international program designed to encourage communities to work together to make a positive difference to the environment (CUW 2011).
      Equation 1
64800=2n*√(x^2+(y/2n)^2 )


scources:
When the Y varies between 100 and 300 meters the height X can be calculated with the following Equation 2:
1. http://www.wur.nl/upload_mm/8/7/e/d4e96e28-e836-46ca-8467-664f529430c8_Plastic%20debris%20in%20the%20ocean.pdf main article used for this
2. http://www.wur.nl/nl/Dossiers/dossier/Plastic-afval-in-zee.htm database with atricles about plastic debris
3.      https://www.theoceancleanup.com/ ocean clean up


==Final project plan==
      Equation 2
After some consideration and research we concluded that gyres were not achievable in our project to clean up. First of all, The gyres were way too big. Second, often, the plastics are too small due to decomposition. Third, there are already some organizations, like the Ocean-Clean-Up , which are trying to develop a plan to clean up the gyres (Other information about the gyres can be found in the appendix). Therefore, we want to have a closer look at our home and trying to focus on the North Sea. This means that we won’t clean up the ocean entirely, but we will make a robot that will prevent the plastics in the North Sea to join any gyre at all. This plan, when executed in the right way, could be implemented at many other shores throughout the world. This means that other big companies can focus on the clean up inside a gyre and our robot will prevent the gyre from getting bigger.
x= √((64800/2n)^2-(y/2n)^2 )  (2)
We hope to get financial support by the government of the Netherlands, “ministerie van infrastructuur en Milieu” to be precise. We think that getting rid of all the plastics in the North Sea will result in a better environment, and a better habitat for all the marine wildlife in the North sea. Furthermore, the Netherlands are characterized by its great amount of water, which means that for a good environment inside the Netherlands we have to start with creating a better environment in the waters surrounding the shores. Furthermore, we know for a fact that the government of the Netherlands want to make an effort in cleaning up the garbage in national and international waters. Therefore we think that the government will be interested to possibly invest in our project.
To determine where we should station the groups of robot we should take the currents in the North Sea near the Netherlands and the sources of the plastics that came from the shores into account. The currents near the Netherlands are as follows:


'''two images'''
In the table below the different Y and X are shown, together with an approximation of n.


The current of the Northsea flows northbound, parallel to the coast of the Netherlands. This is the case for the upstream which contains the floating pieces of plastic. However, this is the case when the there is a high tide. For a low tide the current will shift southbound. This will have no influence on the placement of the robots, because the currents location will not change.
      table 1, the size of the area.
The hot-spots for where to place the robots will be determined by a few factors e.g. shipping traffic, recreational beaches and fishing industry.
[[File:tab1.jpg]]
The three most visited recreational beaches in the Netherlands are Zandvoort, Scheveningen and Renesse. The three biggest harbors of the Netherlands can be found in Rotterdam, Amsterdam and Vlissingen. Fisheries can be mostly found in the province of Zeeland and in Ijmuiden. When we take all these locations into account we can set up the following potential locations to station the robots.


'''image'''
The X was estimated to be around 50 meters and therefore the size of the last row is chosen, with an approximate value of n.


We included Den Helder because it also is an important harbor and the pass way into the Waddenzee. Furthermore, we included a part of the North Sea above the Waddeneilanden because we can use it as a control group, to see how much plastic remains in the current after passing several areas where our robots patrol.
Furthermore, there is assumed that at least 10 agents should be behind each other to gather plastics when the agents in front of them miss them. Furthermore, these extra agents are necessary to cover the area when the other agent is emptying its container.
Our project is an success when at the end of the stream (so at the Waddeneilanden) there is no plastic found after the control group, when there is a high tide. In case of a low tide this control group will be at the area in Zeeland.
The plan is to apply robots which scan and map the coastline of the Netherlands. Furthermore they will monitor the amount of plastic and other waste floating in the area. The AI can choose which path is most efficient to clean up the plastics. The system will be a multiple agent environment which means that is has to stay in contact with other agents to clean up the area more efficient. The difference between high tide and low tide will slightly change the most efficient path that the robot has to go, due to the changing current. The AI will gather and store the plastics found in a compartment inside its own body. When the compartment is full the AI can bring it to several spots where the waste is gathered and where the waste can possibly be recycled. The AI has to deal with sea creatures and sea traffic. The AI has to distinguish the difference between waste and marine wildlife.
Now that the focus of our project is clear we will try to get more into the logistics of the problem.


==Logistics==
In the model part, the optimal amount of agents and the optimal angle in which the agents gather the plastic in the area is chosen by simulating different agent numbers and different angles.
At sea the plastic will be gathered and compressed, but the robot has only so much space for the compressed packages. So as soon as the storage space is full, it has to empty itself. In the previous chapter 5 main locations were given in which the robots would operate. At each of these locations a general gathering point has to be established. So the robots operating in area X each share the same gathering point Y where they can deliver their garbage.  


Now all the plastic is gathered at the shore is will have to be compressed once more. The compressors on the robot only have so much power, so in order to make the transport on land as efficient as possible they have to be compressed by a bigger compressor before the final package can be loaded on its next transporter. Seen from the map of the Netherlands Utrecht would be the best point for a global gathering point of all the plastic, due to its central geographic position. The only 2 realistic forms of transport are either by truck or train. The more remote the gathering point is the harder it is to transport them by train, since railroads aren’t as common as highways. Another aspect is that the dense populated areas often have to burden with traffic jams. The combination of these elements lead to the conclusion that for the remote areas 1* and 5* transportation by truck will be more efficient, while for areas 2*,3* and 4* the train would be a more beneficial alternative.
The question remaining now is where the agents have to be placed to clean up the North sea, while not being disturbed by boats, birds, sailors and so on. It is very difficult to take the birds that rest on the agents into account, therefore the focus lies on human disturb factors. According to the information provided in the environment chapter, the following locations are proposed:
* :
1. The coastline of ‘’Zeeland’’, especially peninsulas ‘’Walcheren’’ and ‘’Schouwen-Duiveland’’ (including hotspots like ‘’Vlissingen’’ and ‘’Renesse’’).


2. The outlet of the harbour of ‘’Rotterdam’’ and ‘’Scheveningen’’.
[[File:loc.jpg]]
      Figure 4, Locations


3. The outlet of the harbour of ‘’Amsterdam’’ and ‘’Zandvoort’’.
These locations are based on tourist locations, harbors and places where rivers go into the sea. These locations are according to state of the art research the hot-spots where plastics goes into the North sea. As can be seen in the figure above, the direction shift of the currents is also taken into account by placing agents on both sides of the river.


4.The harbour of ‘’Den Helder’’ and coastline of ‘’Texel’’.
=Model=
==Model design in CAD==
During the project two models were made, the first one functioned as a basis to make decisions upon, such as what sensors to use, pickup strategy and efficiency among others. The second model created is the final design, this design solved the practical problems and limitations that came up during the rest of the project.


5. The northern part of ‘’de Waddenzee’’ especially the 2 bigger islands ‘’Terschelling’’ and ‘’Ameland’’.
===the first design===
The first thing that came to mind when designing the agent was the fact that it needs to pick up garbage efficiently. A lot of options came up in the initial designing phase. Arms to pick up the garbage, giant nets to trap garbage in etcetera. However these options were not efficient enough, it needed a lot of programming to move the different parts and a lot of energy would be lost in picking up something. So the decision was made to design an agent that could pick up garbage by moving through the water. The main inspiration for this was the nautonomous project and some concept designs made. <ref name=intro5> http://www.tedxdelft.nl/2012/10/tedxdelft-first-performer-boyan-slat/</ref> <ref name=intro10>  https://www.waternet.nl/blog/de-nautonomous-automatisch-drijfvuil-vissen/</ref>


Taking a look at the map of the province of ‘’Utrecht’’ a good collecting point would be ‘’Breukelen’’ or ‘’Woerden’’, since it both places are reachable by either truck and train and they lay well out of the busy ring road of ‘’Utrecht’’. In one of those place a collecting point would be established, where after collection the plastic can be recycled.  
And so the first design was made, it uses conveyor belts on the outside to move the garbage horizontally towards the center in front of the agent and then uses a second conveyor to move it from the water in a compartment. The agent would be kept afloat using two floaters on either side and can move forward and steer using two motors at the end of each floater.  


'''image'''
However, the first design had a few problems. First of the conveyor belts were fragile and would get a lot of pressure put on them when moving through the water against the flow. The outside conveyors were also held in place by relatively thin beams which would break easily. The second problem with the original design was the fact that the front area was big and was not hydrodynamic which would lead to a lot of water friction when moving. And lastly, most of the garbage which would be floating in the seas is up to two through three meters deep in the water. With all the limitations mentioned before, the agent would not be able to pick up all of the garbage. Since the friction forces would get too large when trying to get garbage out of the water.
For the 5 gathering points at the coast the most central point will be chosen as location for collection the pre-compressed garbage. Like already mentioned the plastic will be compressed once more by a stronger compressor before it gets stocked in a container which can be shipped to the main collecting point. Since nobody wants a garbage dump in their backyard a town won’t be the best solutions, but any piece of unused land at the shore not too far from the highway would suffice.


[[File:design1.jpg]]
      Figure 5, First design


== Milestones ==  
===The second design===
Given the sheer size of the plastic soup, stated in the chapter context, cleaning it up will be a difficult time-consuming process. So there are some milestones that have to be set, so the progress can be somewhat measured. Basically those milestones are intermediate objectives we set for ourselves, in order to keep the project realistic in the given time.  
With all the limitations in mind, the second design was made. The new design picks up the garbage in the front and guides it to the surface without a large friction force. From there the blue conveyors will pick it up and guide it upwards. The conveyer belts will drop it off on the green panels which guide it further to the storage compartment. This way the design has fewer dangers in breaking, compared to the first design. It no longer has belts kept in place by thin beams, but a big front plate integrated into the front. The only conveyor belts left are located above water and therefore do not face such large forces as the first design. Secondly, the new design generates less friction due to the front plate and can pick up garbage which is located as deep as two to three meters. All together this will greatly reduce maintenance and power usage. And lastly, it has a compartment that is easy to be taken out and emptied.


The ultimate goal is obviously to clean up the whole plastic soup which currently floats in the oceans, as fast as possible. Another goal is to solve the problem at the source, plastic getting thrown in the oceans. Our robot help prevent the plastic soup from getting bigger.


Starting with the first milestone, removing plastic from the oceans. Since the plastic soup is approximately between 700.000 and 15.000.000 square kilometres big it will take years to clean it up entirely. Another problem is that there isn’t just one soup, there are multiple soups located on different parts of the earth. According to Boyan Slats it would take less than 5 years to clean up one gyre. Since there are the 5 major gyres, with only one cleaning system it would still take over two decades to clean up the plastic, so this would be a realistic milestone time-wise.
[[File:design2.jpg]]
      Figure 6, Second design


Another import issue is the definition of a clean ocean. The soup isn’t necessarily visible plastic, it is also the for a part micro plastics. After a period of time a part of the plastic breaks down into micro plastics, those micro plastics end up in the food chain. As a consequence water gets a certain amount of micro parts plastic per cubic meter. We don’t think it is a realistic milestone to purify the water to that extend, so we will define clean as all the visible plastic removed.  
==Considerations for Cad model==
===Detecting Waste in the ocean===
In this section, three types of agents will be defined. The first are agents that clean the ocean via brute force, this means they keep cleaning the same designated area over and over until they have run out of battery to the point their program tells them to move to a charging station. The second type is agents that use sensors to recognize the shape of plastic and other pollutions and move to the location to clean it up. After they’ve cleaned up the garbage they start scanning again. And lastly, the third type are agents that use ultrasound to scan the ocean for garbage and use the same cleaning procedure as agent prototype two. Below follows a description of the different types, good and bad aspects and both construction and operating cost.


Those were the main milestones for the cleaning part of the project. But to solve a problem one has to start at the source. In this case the plastic being thrown in the oceans. This problem can be tackled in two ways, a legal prohibition or a clean-up service right at the shores. A combination of those will probably work best. Since approximately 80% of the plastic ends up in the soup comes from the shores, the rest is due to the sea-industry. So there is definitely room for improvement on that area. The ultimate goal with our platform solution (see chapter context) is to make the coast plastic free, so the soup won’t grow any bigger than it already is.
====Brute force option====
 
=====Description=====
== Tasks ==
This prototype will have all the basic necessities, this means storage, motors, the ability to float on water, GPS and a mechanism for retrieving garbage from the ocean. Its way of working is via brute force: from the central communication center, it will get allocated to an area of the ocean. Once the agent arrives at its location it will start moving over the whole area, sweeping up every piece of garbage on its way. Once it is done it will start over again until the battery level hits a certain threshold or the compartment is full, after which it will make its way over to the charging station and get its compartment emptied as well.
 
1. State-of-the-art: what is the current situation in our field of research? (2 persons)
  Literature study
  What can be improved?
 
2. Description of the robot + requirements (2 persons)
  What kind of robot? (drone, floating, etc.)
  How does the robot pick up the plastic?
  How does the robot store the picked up plastic?
  How much plastic can the robot carry?
  Where does the robot take the plastic?
  What is done with the plastic once it’s removed from the sea?
 
3. NetLogo (2 persons)
  Create the environment of the robot in NetLogo
  Simulate the robot’s behavior
 
4. Conclusions (everybody)
  Is the robot efficient?
  Will the robot reduce the plastic soup? Or just prevent it from growing bigger?
 
 
State-of-the-art: has to be done at the end of week 5
 
Description of the robot: has to be done at the end of week 5
 
NetLogo: has to be done at the end of week 6
 
Conclusions: has to be done at the end of week 7
 
All the different tasks can start right away, except the conclusions, these will start in week 7.
 
==Different types of cleaning robots:==
 
In this section we will define three types of robots.
 
The first are robots that clean the ocean via brute force, this means they keep cleaning the same designated area over and over until they have run out of battery to the point their program tells them to move to a charging station. The second type are robots that use sensors to recognize the shape of plastic and other pollution and move to the location to clean it up. After they’ve cleaned up the garbage they start scanning again. And lastly the third type are robots that use ultrasound to scan the ocean for garbage and use the same cleaning procedure as robot prototype two. Below follows a description of the different types, good and bad aspects and both construction and operating cost.
 
'''Brute force option:'''
 
''Description:''
This prototype will have all the basic necessities, this means storage, motors, the ability to float on water, GPS and a mechanism for retrieving garbage from the ocean. It’s way of working is via brute force: from the central communication center it will get allocated to an area of the ocean. Once the robot arrives at its location it will start moving over the whole area, sweeping up every piece of garbage on its way. Once it is done it will start over again until the battery level hits a certain threshold or the compartment is full, after which it will make its way over to the charging station and get its compartment emptied as well.
 
''Good and bad points:''


=====Good and bad points=====
Good:
Good:
 
*Simple design
- Simple design
*When the path of cleaning is well designed, it should have few pieces of garbage seeping through its area
 
*Compartments can be smaller due to the fact that more agents need to be used for cleaning
- When the path of cleaning is well designed, it should have few pieces of garbage seeping through its area
 
- Compartments can be smaller due to the fact that more robots need to be used for cleaning


Bad:
Bad:
*Needs a lot more agents than the other two options due to the fact that it is using brute force instead of targeted cleaning, or the cleaning can take much longer than when using the other options
*Even with good cleaning paths the garbage can get through
*More agents means more charging options and more substitution agents to fill up the gaps from traveling agents, which can, in turn, cost more


- Needs a lot more agents than the other two options due to the fact that it’s using brute force instead of targeted cleaning, or the cleaning can take much longer than when using the other options
=====Cost=====
 
The costs of this option will be the least of all the options listed. Due to the fact that this option uses only the features that are absolutely necessary for this agent. But the fact that more agents could be necessary (see above), the costs could go up.
- Even with good cleaning paths the garbage can get through
 
- More agents means more charging options and more substitution agents to fill up the gaps from traveling agents, which can in turn cost more


''Cost:''
====Shape recognition option====
The costs of this option will be the least of all the options listed. Due to the fact that this option uses only the features that are absolutely necessary in this robot. But the fact that more robots could be necessary (see above), the costs could go up.
=====Description=====
 
This prototype will have all the basic necessities as described in the previous prototype, but it will also be outfitted with a camera and shape recognition software. From the central communication center, it will get allocated to an area of the ocean. Once arrived it will start scanning the area for shapes it deems worthy of cleaning up. When it sees a shape it perceives as plastic, it will move over to the location and clean it up, storing it in the compartment. When done it will move on with scanning and the cycle will start over again until the battery level hits a certain threshold or the compartment is full, after which it will make its way over to the charging station and get its compartment emptied as well.
'''Shape recognition option:'''
 
''Description''
This prototype will have all the basic necessities as described in the previous prototype, but it will also be outfitted with a camera and shape recognition software. From the central communication center it will get allocated to an area of the ocean. Once arrived it will start scanning the area for shapes it deems worthy of cleaning up. When it sees a shape it perceives as plastic, it will move over to the location and clean it up, storing it in the compartment. When done it will move on with scanning and the cycle will start over again until the battery level hits a certain threshold or the compartment is full, after which it will make its way over to the charging station and get its compartment emptied as well.
 
''Good and bad points:''


=====Good and bad points=====
Good:
Good:
 
*Targeted cleaning means fewer agents than brute force cleaning
- Targeted cleaning means less agents than brute force cleaning
*Fewer agents means less charging options and substitute agents which means lower construction and operation cost
 
- Less agents means less charging options and substitute agents which means lower construction and operation cost


Bad:
Bad:
*Technology is not yet advanced to the point that it is a feasible option due to the recognition range
*Pixel distortion and image distortion can lead to recognition of non-existent garbage
*In scanning and cleaning garbage can seep through if the software is not correctly calibrated.
*Cameras have no depth perception when using a single camera since it only tracks pixel data and no distance
*Some things that are garbage might not be received as such


- Technology is not yet advanced to the point that it is a feasible option due to the recognition range
=====cost=====
The costs of this option would rise severely owing to the fact that shape recognizing technology is fairly new to the market, and new technologies tend to cost more than technologies already longer existing. The implementing of this technology could also cause a rise in the costs. The size of the sensor would cause an increase in the dimensions and weight of the agent, among other things.


- Pixel distortion and image distortion can lead to recognition of non-existent garbage
====Ultrasound option====
 
=====Description=====
- In scanning and cleaning garbage can seep through if the software is not correctly calibrated.
This prototype will have all the basic necessities as described in the first prototype, but it will also be outfitted with an ultrasound device. From the central communication center, it will get allocated to an area of the ocean. When it gets there it will start scanning the ocean for pieces of plastic and other garbage. When it sees something it perceives as garbage the same procedure as the second prototype is initiated.
 
- Cameras have no depth perception when using a single camera, since it only tracks pixel data and no distance
 
- Some things that are garbage might not be received as such
 
''Cost:''
The costs of this option would rise severely owing to the fact that shape recognizing technology is fairly new to the market, and new technologies tend to cost more than technologies already longer existing. The implementing of this technology could also cause a rise in the costs. The size of the sensor would cause an increase in the dimensions and weight of the robot, among other things.
 
'''Ultrasound option:'''
 
''Description''
This prototype will have all the basic necessities as described in the first prototype, but it will also be outfitted with an ultrasound device. From the central communication center it will get allocated to an area of the ocean. When it gets there it will start scanning the ocean for pieces of plastic and other garbage. When it sees something it perceives as garbage the same procedure as the second prototype is initiated.
 
''Good and bad points:''


=====Good and bad points=====
Good:
Good:
 
*Targeted cleaning means fewer agents than brute force cleaning
- Targeted cleaning means less agents than brute force cleaning
*Fewer agents means less charging options and substitute agents which means lower construction and operation cost
 
*Wide scanning area
- Less agents means less charging options and substitute agents which means lower construction and operation cost
*Tracks depth
 
*Can recognize garbage that is underwater
- Wide scanning area
 
- Tracks depth
 
- Can recognize garbage that is underwater


Bad:
Bad:
*Small objects might not be recognized, as they are seen as noise or get lost in continuous error and noise adjustments.
*Maritime life can be seen as garbage and therefore cleaned up.
*Presumably very sensitive to adjustments
*Might have low accuracy compared to prototype two


- Small objects might not be recognized, as they are seen as noise or get lost in continuous error and noise adjustments.
=====Cost=====
 
The costs of this option will lie in between the costs of the other two options. The ultrasound technology has been on the market for a longer time, so it is further developed, and also cheaper and less than shape recognizing sensors. Another advantage is that waterproof ultrasound sensors already exist and could easily be bought. Ultrasound sensors sell at prices between $10 and $250. The scanning range has to be determined, in order to choose one type of ultrasound sensor, and with that its price.
- Maritime life can be seen as garbage and therefore cleaned up.
 
- Presumably very sensitive to adjustments


- Might have low accuracy compared to prototype two
====Our choice====
We chose the brute force option because the agents work in teams on different spots in the North Sea, which lowers the importance of picking up every piece of waste that passes the spot in which the agent works. If one piece passes one agent, another agent can pick it up. For this agent, there is no need to add the extra features mentioned above, and this will only increase the costs of the agent.


''Cost:''
===Picking up waste from the ocean===
The costs of this option will lie in between the costs of the other two options. The ultrasound technology has been on the market for a longer time, so it is further developed, and also cheaper and less than shape recognizing sensors. Another advantage is that waterproof ultrasound sensors already exist and could easily be bought. Ultrasound sensors sell at prices between $10 and $250. We need to determine the scanning range in order to choose one type of ultrasound sensor, and with that its price.
There are different options from which can be chosen regarding picking up waste from the ocean. A simple fishing net, a sort of arm with a basket attached to it, and a slide which would force the waste to the surface of the ocean, where it could be picked up by a conveyor belt, were all considered. Below, the different (dis-)advantages and costs of every option are discussed.


'''Our choice:'''
====Fishing net====
We chose for the ultrasound option, because this extra added feature is worth its costs. It adds efficiency to the robot in a way that it knows where objects in the sea are in its direct environment.
=====Description=====
This option would be about the same as the fishing nets used by the fishing industry (see Figure below), but smaller and used only two meters below the surface of the water.  


'''Our Goal:'''
With the use of our robot we want to make sure that all the plastic waste that originates from the coast of the Netherlands is cleaned up and therefore doesn’t move to the gyres.


== Information gathering ==
[[File:Fishing.jpg]]
1. Is er voldoende behoefte aan een oplossing voor dit probleem, zodat de investering daadwerkelijk gemaakt gaat worden?
      Figure 6, Fishing industry boat.


Er zijn vele organisaties die zich bezig houden met dit probleem, en die er ook echt het probleem van inzien. Niet alleen de vervuilingskwestie op zich vormt volgens deze organisaties een probleem, maar ook de gezondheidskwesties wanneer de plastics afbreken en in de voedselketen terecht komen. In deze organisaties worden vaak veel geld investeert vanuit de regering, echter vaak zijn deze organisaties lang bezig met het vinden van een oplossing en steken ze tot nu toe vaak op concept ideeën. Als wij dus kunnen aantonen dat ons project dé oplossing is, zal er zeker geld in geïnvesteerd worden.
=====Good and bad points=====
2. Welke soorten plastic voorwerpen komen het meest voor als afval in de Noordzee?
Good
*Can cover large patches of ocean
*Many different net sizes to choose from
*Many options for the size of the holes in the nets
*Waste of all sizes can be picked up


Verschillende instanties zoals Rijkswaterstaat en Stichting de Noordzee monitoren het (plastic) afval op de stranden en in de Noordzee. Hieruit is een top 10 samengesteld van de meest voorkomende afvalitems;
Bad
a. Touwen en netten
*Hard to determine the right size of the holes in the net, too large and waste may not be trapped, too small and other things than waste may be trapped in the net
b. Stukjes plastic
*Fish that swim close to the surface of the water could also be trapped by the net
c. Plastic zakken
*How to empty the net into the onboard storage container without humans on board?
d. Doppen
*Takes up a lot of space
e. Snoepverpakkingen
f. Ballonnen
g. Plastic drank flessen
h. Hout
i. Plastic voedsel verpakking
j. Industrieel plastic


3. Wat is de voornaamste bron van plastic afval aan de Nederlandse kustlijn gezien?
=====Cost=====
Recreational fishing nets aren’t that expensive, but when looking at more professional fishing nets, the costs can rise pretty quick, they can cost between 100 and 200 euros.  


Meer dan de helft van het afval komt van de maritieme sector. Dus logischerwijs zijn de grote havensteden geografisch gezien een ‘’hotspot’’ wat betreft het dumpen van plastic afval in de Noordzee. De overige vervuiling komt voornamelijk bij de strandgangers vandaan, dus ook drukbezochten stranden zijn potentiële schoonmaak plaatsen.
====Arm with basket====
=====Description=====
A visual representation of this option can be seen in the image below. A basket, with small holes (so the water doesn’t end up in the storage container), can move up and down around an axis, picking up waste objects.


4. Zijn er zogeheten ‘’Hotspots’’ waar het afval zich (onder invloed van stroming) verzamelt, zijn deze op land en/of op zee? Zo ja, waar bevinden deze plekken zich?


Het is in het algemeen het geval dat het plastic qua afmeting kleiner wordt naarmate men verder uit de kust gaat kijken. Onze focus ligt voornamelijk op de grotere stukken plastic, dus in combinatie met de vorige vraag kunnen de hotspots worden vastgelegd rond de uitmondingen van rivieren en havens en langs de kustlijn van drukbezochte stranden.
[[File:Basket.jpg]]
      Figure 6, Arm with basket agent.


5. Aan welke orde van grootte moeten we denken bij de hoeveelheid plastic afval die in de Noordzee drijft, heeft u hier precieze cijfers van?
=====Good and bad points=====
Good
*Can pick up every piece of waste passing
*The size of the basket can vary, so bigger waste objects can also be picked up


Wat betreft de bodemvervuiling van de Noordzee spreken we over 110 stukken plastic per km² in de Noordzee. De vervuiling langs de kustlijn bedraagt 380 stukken afval per 100 meter strand.
Bad
*The friction force of the water causes the need of a strong motor or servo for turning the axis
*What material is the basket made from? There could be the need of designing this from scratch, and this could cost a lot of time
*If the basket is in the process of picking up a piece of waste, and another piece passes, it can’t pick up the other piece of waste, this is inefficient
*All the electronics need to be at the back of the agent, which can cause the agent to be very heavy in the back and therefore unstable


=====Cost=====
Since this option will be needing a strong motor or servo, the costs can rise pretty quickly. Also, the material of the basket could be something that has to be designed from scratch, which can cost a lot of time and money. A simple fishing net could be used, of course, this could also solve the problem of the friction force of the water. But using a simple fishing net gives the problems mentioned in the section of the simple fishing net.


6. Op welke dieptes bevindt het plastic afval zich voornamelijk?
====Slide with conveyor belt====
=====Description=====
This option will use the upward force of water. On the front of the agent, a slide is made. When a waste object is in the path of the agent, it will bump against the slide, the slide will force the water and the waste object upwards (toward the surface of the ocean). When at the surface, a conveyor belt, made of plastic, with plastic spikes, will take over from the slide, and bring the plastic object further upwards until it falls into the storage container. The conveyor belt will have holes in it, so that the water, which has been forced upward, falls back into the ocean.


De grootste concentratie afval is rond of op het oppervlakte. Er is gemeten tot op een diepte van 5 meter en hieruit bleek dat 80% van het afval zich bevond in de eerst 2-3 meter.
=====Good and bad points=====
Good
*Every piece of waste in the path of the agent is picked up when using this method
*Using forces outside the agent to pick up waste (water’s upward force)
*All the agent has to do is sail its path and keep the conveyor belt running
*No fish and other things than waste will be picked up using this method


7. Zijn er vergelijkbare projecten zoals deze en zo ja, wat houden deze in?
Bad
*All waste objects that aren’t in the agent’s path aren’t picked up
*It may cost a lot of energy to keep the conveyor belt running all the time


Een vergelijkbaar project is de ocean clean up. Het idee is dat op grote schaal afval uit de North pacific gyre gehaald wordt met behulp van 2 lange armen. Echter is dit project op een veel grotere schaal met hogere concentratie afval per km^2 dus niet echt toepasbaar op ons probleem.
=====Cost=====
The slide and the conveyor belt can both be made out of plastic, which just has to be shaped in a specific form. Since the form of a slide is used, the costs of a children’s slide are used as a base for the costs of the slide. These cost around 30 euros. For a plastic conveyor belt of 60 cm wide, a price of about 150 euros per meter has been found.<ref name=Conveyor>http://www.safeconveyor.com/Modular-Plastic-Conveyor-Belting-Pricing.php</ref>


Een ander project is opgezet door waternet. Het heeft een autonome robot gemaakt die heel erg op onze robot lijkt en door het water vaart en afval op een loopband met zich meeneemt.
====Our choice====
The choice fell on the slide option. One of the major advantages was the fact that no harm is done to marine wildlife when using this method. The goal is to clean up the ocean, not damage its ecosystem. Furthermore, the disadvantage concerning not picking up every piece of waste can be countered by the same argument used for the brute force navigational option: other agents can pick it up. The simplicity of the solution is also a plus, the agent does not need any extra sensors of knowing when to rotate (like with the basket). The extra costs for the slide and the conveyor belt are well spent if marine wildlife can be spared.


==Netlogo model==
In this part of the project, a model was made that simulates a certain amount of agents cleaning up an area of the North sea with a width of 300 meters and a length of 54 meters. The purpose of the model was to determine the optimal number of amount of agents by simulation. As said earlier in the chapter about the strategy, the velocity of the agents has to be at least 3 meters per seconds. In the model, this has become 4 meters per seconds because the chance of missing pieces of plastic is smaller. This is determined by simulating the model a few times.


Een ander vergelijkbaar project is opgezet door de recycled Island foundation. ze maken een soort vallen en plaatsen deze aan de kust van Rotterdam op strategische plekken en vangen op die manier plastic op.
The agents have to empty their container when their containers are full. In the total width of 300 meters, there are 6 stations, where the agents can empty their containers and refill their energy level. The initial energy is chosen very high, so the chance of getting the container full is greater than the chance of running out of energy. These stations are located at 25, 75, 125, 175, 225 and 275 meters. The charge time is estimated at around 8 ticks because the emptying the container will be executed as efficiently as possible.


https://www.youtube.com/watch?v=BYXlv8fgj80&feature=youtu.be
The rest of the model can be seen by clicking on the link below:


==Garbage distribution==
https://drive.google.com/file/d/0B-QPPQg1oPoeOTNNUlpybFNkemc/view?usp=sharing


Before we can start with designing our robot we need to have an impression of where our target, the garbage, is located. After contacting several organizations we were able to make a proper estimation of how the garbage is disturbed in the Northsea.  
The result of the simulation with the respect to the number of agents are given in the tables located in the chapter data of model in the Appendix. When the date retrieved is taken into account the following can be concluded. According to the model 13 agent are needed with a agent distance of 2.5 meters. This means that 1,64 percent of plastics are missed.


Starting off with the depth of the garbage, research has shown that in a water column of 5 meter, starting at the surface, 80% of the it can be found in the top 2 to 3 meters [1]. However, these numbers follow from measurements done in the North Atlantic Gyre, so do they also hold for the situation in the Northsea? Without going to much in physical detail, we will try to explain if the North Atlantic ocean is comparable with the Northsea. A object floats if it has a smaller density then the liquid. Density is a ratio of mass and volume and since these quantities are the same in both situations we can assume the results of the study are also applicable for the Northsea.


The second variable is the distance of the plastic to the coast. Since we couldn’t find any reports with the necessary data we contacted Rijkswaterstaat. It turned out there isn’t any specific data, but the rule-of-thumb is; the further away from the coast, the smaller and less dense the garbage gets. Combining this information with location of the hotspots (outlet of rivers, harbours and beaches), only a few potential locations remain.  
=Discussion=
During the project, certain aspects of our progress could have been executed a lot better. Especially at the beginning of the project, the progress went very slow. We could not make decisions on what to focus on during the rest of the project, which resulted in a few shifts of our problem’s composition. When our problem was finally stated in a clear manner, we could finally focus on problem-solving, which resulted in the solution given in this report.


1. The vertical distribution of buoyant plastics at sea: an observational study in the North Atlantic Gyre – J. Reisser, B. Slat, K. Noble,  K. du Plessis, M. Epp, M. Proietti, J. de Sonneville, T. Becker and C. Pattiaratchi
Another problem in our progress was the explanation of choices that we made with respect to the RPCs. Some choices were made by making assumptions, however, it was not clearly stated in our wiki at the time. Another set of choices were based on facts, however, lacked the sources needed. In short, we had to elaborate more on the choices we made, so the tutors could see why those choices were made validly. We have learned a lot about the importance of elaboration of choices and it also led to discussions that have improved our project in the end.


==Requirements and inspirations==
In the group, we had sometimes trouble with meeting up and finding time to work on the project as a group. If we had more time, then we would be exploring more options for strategies and optimizing it  
Requirements:
more.  
The robot needs a container were it can store retrieved plastic. The dimensions of this container are a width of 0.8 meters, a length of 0.8 meters and a height of 1,5 meters. 
The container needs to be able to be taken out of the whole boat easily. This can be done with handles at the top sides. By making clips that hold the container in the boat, it cannot move when it is operating. However when it has to be taken out of the boat it should be easily loosened with those clips.
It also means that when the container is full it should know that it has to go to a point where it can empty itself. This can be done for example by a sensor that sees, that when the plastic is higher than a certain point it should empty itself.  


An agent needs to retrieve plastic by using a net. The net is attached to a rotating engine. This way it can fish the plastic out of the sea and put it in the container. This can be seen at the picture below. This is only a picture to be used for the net idea itself. The boat itself does not look like this at all.
In this project, we could have benefited by making a more structural
We want to have a net that has holes in it that are 1,5 cm by 1,5 cm. This way not all the plastic falls out of the net, through the holes itself. The net should be also 1.5 meters wide and with a length of 1 meters.  
planning because now the state of the art research went slowly. We should have contacted the different organizations earlier in the project. The contact we made with the organizations provided information which we used in the problem-solving part of the project.  


[[File:Boat.png]]
If we had contacted them earlier in the project, we could have found a solution much earlier, which would have resulted in more time for optimization and model making.  


An agent needs to be able clear the whole area, and to be able to know which parts of the area it has covered. Therefore it needs understanding of the currents as well. The currents go with a speed of around 4 km/h which is 1,11 m/s. A GPS is used for knowing where it has been.  
=Conclusion=
The goal of our project was to make sure that waste located in the North Sea doesn’t move to the gyres in the open ocean. To do this, we decided that an ocean cleaning agent needed to be designed to sail the North Sea and collect the waste floating there.
We started out with researching the state-of-the-art of this subject. This included literature research and contacting organizations which might know more about this subject. Using the information gathered from this research we started the design of the agent.
The most important choices were the navigational strategy and the method of picking up the plastic because only then a model for the agent could be made, and a NetLogo environment could be created.  


The robot needs two motors, so it can steer and move forward. The motors have to be powerful enough so the agent can reach the desired maximum speed of 2.5 m/s.
The goal of the agent was to pick up as much waste, if not everything, as possible. A strategy has been developed to reach this goal. The strategy that has been developed, which is stated in the report, has been tested in NetLogo and it only misses 1,64 percent of the waste. This efficiency is accomplished when 13 agents, with a distance of 2,5 meters between them, are working. The workspace has a width of 300 meters and a length of 54 meters. We consider this a strategy that works very well.  


-The agent needs to have a width of 2 meters
Though our agent does pick up most of the plastic it encounters, and when working in teams, 98,36 percent of the plastic is picked up, the North Sea will never be totally clean if dumping of waste into the ocean doesn’t stop. If the dumping keeps going, the ocean will still be polluted with waste, and our agent would need to work forever. In the scenario where the dumping of waste into the ocean stops, our next focus could be to clean up the gyres in the ocean. The ultimate goal is, of course, to make sure that there is no waste at all in the oceans, but we still have a long road ahead before this could ever be achieved.
 
-The agent needs to have a length of 2 meters
 
-The agent needs to have a height of 1,5 meters
 
The robot needs an ultrasound sensor on the front of the agent. This way it can look how far a unit of plastic is and this way it will know when to reel in the plastic units.  
 
The robot needs GPS. This way it can see where it has been, where it should go and when it is connected with other agents, they also know where the other robots have been and where they are going.
The robot needs to be able to be controlled manually, when it is required too. For example, when the weather gets extreme and the waves get very high, so it will be dangerous the unit should be able to be steered back manually to a safe place.
   
   
An agent needs a battery life of (dependent of the area covered per robot. It would be a preference to have it fully powered by solar energy)
It needs a speed of more than 4 km/h. The current of the sea can be at the most 4 km/h so that means that if we want to make speed in those parts of the ocean, it has to go faster than that. 4km/h is about 1.11 m/s. If we want a decent speed at which we can pick up plastic, the robot has to go at least 2,5 m/s.
http://www.catamaranschool.nl/stromingengetijden.html
Its lifetime has to be 10 years. When an agent is build, it should be able to operate for quite some time and not break after a few years already.
An agent needs to be multi-hulled. One left of the container and one right of the container. It will look a bit like a catamaran. In the middle is the container and in front of that is the fishing net. On the back of each hull there is a motor. This way it can steer just like a tank with caterpillar tracks can do it. If it wants to go right, it just turns on the left motor.
''Inspirations''
Preference:
The solar voyager is a solar powered boat that is currently being tested. It’s currently crossing the Atlantic Ocean. This project can server as inspiration to make our robots fully solar powered.
http://www.solar-voyager.com/index.html
Roboat:
Roboat is the world’s first large-scale research that explores and tests the rich set of possibilities for autonomous systems on water. “Imagine a fleet of autonomous boats for the transportation of goods and people,” says Carlo Ratti, Professor at MIT and principal investigator in the Roboat-program.
“Roboat offers enormous possibilities,” says Professor Arjan van Timmeren, AMS Institute’s Scientific Director, “as we’ll also be exploring environmental sensing. We could for instance do further research on underwater robots that can detect diseases at an early stage or use Roboats to rid the canals from floating waste and find a more efficient way to handle the 12,000 bicycles that end up in the city’s canals each year.”
The first prototypes of Roboat will be visible in the waters of Amsterdam in 2017.
Model:
We also started to work on a model for the robot in NetLogo. It is not yet finished, however it is a good start.
http://www.ams-institute.org/roboat/
Sea Machines builds Autonomous Control & Remote Command Systems to enhance the operation of existing or new build marine vessels.
http://sea-machines.com/#technology
==Appendix==
'''Table'''
Sensors
The robot follows a certain path according to their sensors. The camera first percepts its area. When it does this, it also scans the sea. This can be done with a laser, that can recognize plastic and other things. When the camera percepts an unknown unit, it will first look at it and ask itself. Is this plastic or not? The plastic can be recognized by common shapes of plastic bottles for example. When it is not plastic it will communicate this with other agents, so that they won’t take a look at it and already know it is not plastic. Then it will sail further to another location and start over again. However when it is a plastic unit, it can use ultrasound. This sends soundwaves to the object and some waves will be reflected back. This can measure the distance between the object. Then it will navigate with the GPS to the plastic unit and pick it up. When it moves toward the plastic object, it also communicates with the other agents to let them know, it already takes care of that particular plastic unit. After it has picked up the plastic, it will put it in its storage. After this the cycle repeats itself. However, when the storage is full, it will go to a station to get rid of its content. It will also update the agents in the area that it is emptying its storage, so that they can also go to that area. There is a second moment, when it has to go back. If the battery is lower than 10/15 % it will also go back to the station, to reload. The Agent also has to communicate that with the other agents, so it can be replaced by an agent that has a full battery. 
The AI will be a floating robot, that can take the plastic out of the sea. It will have a container at the middle in the back, where the picked-up plastic will be put. Here it will also be compressed. The plastic will be put into the container by a conveyor belt. The plastic will be shoved on the conveyor belt by 2 rotating arms, that will shove the plastic in a place where it will be put on the conveyor belt. On the 2 sides of the container, there will be 2 beaters. At the back of the 2 beaters there are is a motor for each beater. This way it can also steer, just like with caterpillar tracks. Under the conveyor belt is enough space for the electric parts that are needed to steer the robot. There is enough space for the camera and other sensors on the robot. The belt of the conveyor belt has to have some profile in it or very small spikes, so it has enough friction for the plastic unit not to fall off. There also is a small wall on each side of the belt, so the plastic unit doesn’t fall off that side.
Sensors:
1.    Camera, so it can perceive its environment.
2.    GPS, so it knows where it is.
3.    Communicating device to communicate with other agents.
4.    Ultrasound sensor, so it can measure the distance to different objects.
Process:
1.    It percepts the plastic unit or it gets a signal that there is a plastic unit on its way.
2.    It sails to the plastic unit.
3.    It analyses the situation. Is it floating or is it stuck in coral for example.
4.    Find a way to grab the plastic unit.
5.    The arms reel in the plastic unit.
6.    The plastic unit goes on the conveyor belt.
7.    The conveyor belt puts the plastic unit in the container.
8.    When there is a significant amount of plastic in the container it will compress it.
Important notes:
1.    It is important to note here, that it will not compress every time it finds a plastic unit. It would be a waste of energy to do that with every plastic unit.
2.    It is also important to note, that the conveyor belt is not active all the time. It Is only active when  a sensor senses that a plastic unit is reeled in. Otherwise it would be a waste of energy.
Old Design:
[[File:Knipsel.PNG]]
[[File:Knipsel 2.PNG]]
The first design made had a few problems. First of the conveyer belts were fragile and would get a lot of pressure put on them when moving through the water against the flow direction. The outside ones were also held in place by relatively thin beams which would break easily. The second problem with the original design was the fact that the front area was big and was not hydrodynamic which would lead to a lot of water friction when moving through the water. And lastly most of the garbage which would be floating in the seas is two through three meters deep in the water. With all the limitations mentioned before, the agent would not be able to pick up all of this. Since the friction forces would get too large when trying to get garbage out of the water which is not floating at surface level.
New Design:
[[File:Knipsel 3.PNG]]
The new design picks up the garbage in the front and guides it to the surface without a large friction force. From there the blue conveyers will pick it up and guide it upwards. The conveyer belts will drop it of on the green panels which guide it further to the storage compartment. This way the design has less dangers in breaking, generates less friction and can pick up garbage which is located as deep as two to three meters. This will greatly reduce maintenance and power usage.
With the design of the robot here, it is a matter of making a strategy for the robots of how they are going to collect the garbage in a certain area. The strategy we thought of is presented down here, based on the design of the robot.
PICTURE
When we only look to the surface of water, a strategy is not required, because everything of the garbage can be collected when sailing every direction. However with the new design it is necessary to sail against the stream. The design has arms that will push the garbage to the surface when the stream goes against it. However when the robot will be sailing parallel to the coastline, it will take a lot of robots to clean the surface of a length x. every robot has to sail next to each other to collect everything. That’s why a zig zag strategy is chosen. Here it will be presumed that a surface of width y and length x meters has to be kept clean. When the tides change direction, the robot should be turning around. The tides change every 6 hours[1]. Further it is known that the current in the north sea is equal to 1,5 m/s. As a group we’ve chosen that the robot should go at least 3m/s. This means a robot can travel 64800 meters in 6 hours. Further it is presumed that the robot over the total y meters n times a zig zag pattern performs. This means it can be calculated with the following formula:
64800=2n*√(x^2+(y/2n)^2 )
When the y is varied between the 100 and 300 meters the length x can be calculated with the following formula:
x= √((64800/2n)^2-(y/2n)^2 )
In the table down here the different values of y can be given with an output x.
TABEL MOET EVEN GOED WORDEN INGEVOERD:
Y n x
100 m 200 161,99 m
150 m 300 107,99 m
200 m 400 80.99 m
250 m 500 64,79 m
300 m 600 53,99 m
!!!!!!!!!!!!!
We think that the last option with y = 300 meters and x = 54 meters the best. Every zig zag has a width of half a meter. Further it would seem good to put 10 robots behind each other with a distance z, for control if it should miss a piece. Also it is necessary to do this, for when the other robot is full. The amount of robots is based on the speed of the current. It is also possible to put more robots next to each other to clean more than 54 meters long . It seemed convenient to pick the z that the robot has a head start of half a zig zag on the robot behind it.
Now is the question where we can put these robots. To perform this strategy without problems, the robots should be able to do their work undisturbed. Disturbances can be: Boats, Birds, Sailors, etc. Of course it is hard to take birds that want to rest on the boats into account. Measurements can be taken for this however we want to focus on human disturbances. To make this strategy work, it means that some parts of the coast in the North Sea have to be reserved for only the robots. Big ships and recreational boats should be able to easily go around these parts. The first division of the robots looked like this:
PICTURE
However these places are based on sources from the plastic. However if we want to let our robots look for garbage, they will be an obstacle for human traffic. The boats around it will disturb the strategy and the robots will disturb the traffic. The places are now adjusted to take this into account.
PICTURE
As you can see, we’ve used the sources from the plastic however we put them at the sides of those places. It is put on both sides, since the tide will turn the current.
[1] http://www.ebvloedgetijde.nl/
==Effects on the environment==
The North Sea is a special area of high biodiversity and high productivity. Humans are using the sea for centuries for fishing and shipping. Because of this, some areas in the North Sea are disturbed, polluted and over-fished. The bottom is regularly plowed by bottom trawl fishing, and is filled with cables and pipes. There are oil and gas platforms, sand is taken from the seabed and there’s being practiced by the military. In addition, there are more and new activities such as wind farms or possibly islands in the sea. This increases the pressure on this unique area and nature, which has already greatly changed, giving it no chance to recover.
Most harm to the environment is due to damaging/interfering with the seabed. This is mostly done by fishing, or to be more specific bottom trawling. In 2016, 14% of the dutch North Sea seabed was appointed as protected area. Effective protection means denying any activities, interfering with the seabed, so the seabed has time to recover. Our agent doesn’t go as deep as the seabed, so our agents won’t harm the seabed and will therefore be way less harmful to the environment as most fishing activities.
'''Protected areas, Natura 2000'''
Along the coast various Natura 2000 sites have been designated. These are the Noordzeekustzone, Voordelta, Vlakte van de Raan en Deltawateren. There are special rules and regulations for these areas. In some of these areas, fishing and transport ships are still allowed,. An overview can be found in the following pdf.
https://www.noordzeeloket.nl/images/Mariene%20ecosysteem_4852.pdf
== Vragen laatste meeting ==
Wat is de deadline wat betreft de wiki, ligt deze aan het eind van de week of op het moment van de presentatie?
Moet op de wiki het proces beschreven worden dat de afgelopen 8 weken is doorlopen, of enkel het eindresultaat?
In hoeverre moet de wiki lijken op bijvoorbeeld een OGO verslag?
== Links ==
links:
drinkwaterzuivering:https://www.evides.nl/drinkwater/hoe-wordt-mijn-drinkwater-gemaakt
waterzuivering (idee): http://www.nationalgeographic.nl/artikel/oceanen-weer-schoon-dankzij-boyan-19
http://www.plasticsoupfoundation.org/feiten/gevolgen-voor-het-milieu/


http://www.plasticsoupfoundation.org/feiten/gezondheidseffecten/
=Appendix=
==Garbage distribution==
Before the designing of the agent can start an impression of where our target, the garbage, is located is needed. After contacting several organizations a proper estimation could be made of how the garbage is disturbed in the North sea.  


http://www.icgrevelingen.nl/blog/2016/01/14/cleanriverproject/
At first the depth of the garbage will be elaborated. Research has shown that in a water column of 5 meters, starting at the surface, 80% of it can be found in the top 2 to 3 meters <ref name=depth>The vertical distribution of buoyant plastics at sea: an observational study in the North Atlantic Gyre – J. Reisser, B. Slat, K. Noble,  K. du Plessis, M. Epp, M. Proietti, J. de Sonneville, T. Becker and C. Pattiaratchi </ref>
. However, these numbers follow from measurements done in the North Atlantic Gyre, so do they also hold for the situation in the North sea? Without going too much in scientific detail, we will try to explain if the North Atlantic ocean is comparable with the North sea. An object floats if it has a smaller density than the liquid. Density is a ratio of mass and volume and since these quantities are the same in both situations we can assume the results of the study are also applicable for the North sea.


Context:
The second variable is the distance of the plastic to the coast. Since we couldn’t find any reports with the necessary data we contacted Rijkswaterstaat. It turned out there isn’t any specific data, but the rule-of-thumb is; the further away from the coast, the smaller and less dense the garbage gets. Combining this information with the location of the hot-spots (outlet of rivers, harbors and beaches), only a few potential locations remain.


http://www.techrepublic.com/blog/european-technology/the-long-range-drone-that-can-keep-up-with-a-car-and-fly-for-an-hour/\
==data of model==


http://www.boatdesign.net/forums/sailboats/speed-average-sailboat-18365.html
      Table 3, Dataset 1
[[File:data1.jpg]]
     


Milestones:
      Table 4, Dataset 2
[[File:data2.jpg]]


https://www.theoceancleanup.com/


http://www.tedxdelft.nl/2012/10/tedxdelft-first-performer-boyan-slat/
      Table 5, Dataset 3
[[File:data3.jpg]]


https://plasticsoepsite.wordpress.com/onstaan-plasticsoep/
==Environment==
[[File:coast1.jpg]]
      Figure 7, Fishing areas North sea<ref name=visserij></ref>.


https://www.theoceancleanup.com/technology/ Ocean clean up
[[File:coast2.jpg]]
      Figure 8, Shipping routes North sea<ref name=fig8>https://www.noordzeeloket.nl/images/20141111_1410-0334-004_Scheepvaart_d02_1202.pdf</ref>.


http://www.wur.nl/nl/Dossiers/dossier/Plastic-afval-in-zee.htm wetenschappelijke artikelen
= References=
<references />

Latest revision as of 18:50, 13 April 2017

Group Members

Student ID Name
0957942 N.S.A. Messaoudi
0958470 J.J.J.B. Verstappen
0955491 C. van Otterlo
0939540 M.J.M. Smits
0956810 W.J.P. Goudriaan
0953119 J.I.A. Spapen

Introduction

Since 1945 plastic is inseparable from our society, where it brought us great fortune and great use. It is used to carry drinks, package foods, toys, etc. Whereas it has a good side that helps humanity, it also has its downsides. A lot of people throw their garbage, of which most is plastic, very easily on the ground and in rivers. This means the mainland and the oceans get polluted, instead of the plastic being recycled, when it is thrown away. On the mainland, there are a lot of organizations, which focus on preserving the mainland’s environment. For example by sending people to collect waste next to roads and beaches. A number of organizations in the seas and oceans are, however, greatly outnumbered. While the organizations on the mainland can hardly keep the pollution at a steady level, the pollution in the seas and oceans has risen exponentially for several years already. The plastic in the ocean decomposes gradually which results in a highly soiled sea which is more difficult to clean up. Even when the plastic decomposes into small parts, it affects and influences the marine ecosystem as a whole. A fish cannot tell food and plastic apart and slowly gets poisoned and killed by the toxic plastic in its stomach. The same happens to many birds that get their food out of the water.

A number of organizations in the seas and oceans are, however, greatly outnumbered. While the organizations on the mainland can hardly keep the pollution at a steady level, the pollution in the seas and oceans has risen exponentially for several years already. The plastics in the ocean decompose gradually which results in a highly soiled sea which is more difficult to clean up. The small parts of plastics influence the marine ecosystem as a whole. Fish cannot tell food and plastic apart and slowly gets poisoned and killed by the toxic plastic in its stomach. The same happens to many birds that get their food out of the water and even humans can be affected by this. If a fish gets poisoned and a human will eats that fish, then the human will also be affected by the effects.

The plastic that gets in the sea, gathers in so-called ‘gyres’. These are huge area’s to which the plastic floats due to the current. It slowly floats in circles in the same area. There are 5 huge gyres around the world. See Figure 1 below.


Gyres.jpg 

          Figure 1, the 5 gyres in the world

Currently, there is a project that is cleaning up these gyres. They put down a giant net in the gyres and let the current of the gyres pour the plastic in the gyres. This way all the plastic gets pushed into the net and collected in one place. However cleaning up the gyres alone is not enough. The plastic that is in the gyres came from somewhere and the gyres are still growing every day. That’s why it is also important to prevent the gyres from getting bigger, by cleaning up the plastic closer to its source.

The thing that has to be accomplished, is preventing the gyre from becoming bigger. Prevention starts with looking at the coast of The Netherlands. The goal that is set for this project is to try to let no plastic/garbage pass through the coast of The Netherlands. The current of the North Sea along The Netherlands is from the bottom to the top or the other way around, which depends on the tides. This is very convenient for setting up places for agents. When a plastic/garbage unit is not cleaned on the beginning of the flow, then it will be cleaned up later by another agent that is in another place at the coast. Also, a lot of plastic comes from the beaches and the harbors. It is, therefore, important to stop the flow of plastic/garbage as close as possible to the source. This is the reason why the agents are placed along the coast of The Netherlands. This will mean that the plastic/garbage will be cleaned up before it comes in the gyres.[1] [2] [3] [4] [5] [6] [7] [8]

Current situation

In order to tackle the problem, a good overview of the situation need to been set. This is done by writing down all the questions about the garbage problem in the North sea and then the searching for answers started. The strategy was as follows; first search for the answer on internet to get a basic intuition and then contact several organizations asking them all the same questions and combine all this information into one final answer.

The main sources that were used are either reports or the organizations that were contacted. The following are the reports used:

  • Wat spoelt er aan op het strand – Stichting De Noordzee
  • Mariene Strategie voor het Nederlandse deel van de Noordzee 2012-2020 – Rijksoverheid
  • Jaarverslag 2015 – Stichting De Noordzee
  • Guideline for Monitoring Marine Litter on the Beaches in the OSPAR Martime Area – OSPAR commission
  • The vertical distribution of buoyant plastics at sea: an observational study in the North Atlantic Gyre – J. Reisser, B. Slat, K. Noble, K. du Plessis, M. Epp, M. Proietti, J. de Sonneville, T. Becker and C. Pattiaratchi

The following organizations were contacted:

  • CBS
  • Rijkswaterstaat
  • Kustwacht
  • Clean up
  • Greenpeace
  • Stichting de Noordzee

Of course, not all organizations were as helpful, but there was enough response to get a complete answer to all the questions there were. Here are the questions that were asked, followed by the answer in italic.

  • Is the problem significant enough for organizations like the government to invest money in?

There are several organizations searching for solutions for this problem, which it is significant enough to be solved. Not just the pollution issue in itself is a problem for these organizations, but also the health issues when the garbage breaks down and ends up in the food chain. The government is the biggest investor since it is a societal matter and it is hard for a profit-seeking company to make money off. So if we can show the government that our project is the solution to this problem, our project could be worth investing in.


  • Which kinds of garbage objects are most common in the North sea?

There are multiple organizations (Rijkswaterstaat, Stichting Noordzee en NIOZ) that monitor the garbage on the beaches and in the North sea. With this data a list was composed, summing up the top 10 most found garbage objects in and around the sea.

    • Ropes and nets
    • Plastic pieces
    • Plastic bags
    • lids
    • Candy wrappers
    • Balloons
    • Plastic bottles
    • Wood
    • Plastic food packaging
    • Industrial plastic contents
  • Who are responsible for the garbage in the North sea and where are they located at the coastline?

More than half of the waste comes from the maritime sector. So logically the major port cities are geographical hot-spots with regard to the dumping of plastic waste in the North sea. Other pollution comes mainly from the people visiting the beaches, so crowded beaches are also potential hot-spots. Also, the rivers are highly polluted which makes the places where the rivers goes into the ocean as a dumping hot-spot

  • Are there hot-spots were the garbage gathers (under influence of the current), are these hot-spots on the coastline and/or in the sea? If they exist, where can they be found?

Generally speaking, the plastic gets smaller in terms of size the further one distances itself from the coast. Our focus is mainly on the larger pieces of plastic, so in combination with the previous question, the hot-spots can be recorded around the mouths of rivers and harbors and along the coastline crowded beaches.

  • What is the order of magnitude of the garbage that is in the North sea, do you have exact numbers?

Regarding soil pollution of the North Sea, we are talking about 110 pieces of plastic per square kilometer in the North sea. Pollution along the coastline is 380 pieces per debris 100 meters beach.

  • At what depth is can the garbage be found?

The greatest concentration of debris is around or on the surface. There has been measured up to a depth of 5 meters, and from this, it was found that 80% of the waste was in the first 2-3 meters. Which will be further explained in the chapter garbage distribution in the Appendix.

  • Are you familiar with a comparable project like ours, if so could u give us some information about the projects?

A similar project is the ocean clean up. The idea is to be achieved on a large scale waste in the North Pacific gyre using two long arms. However, this project is on a much larger scale with a higher concentration of waste per km ^ 2 so not really applicable to our problem.

Another project was undertaken by water network. It has created an autonomous agent, named Nautonomous, which navigates through the water and gathers waste on a treadmill, this agent can be seen in Figure 2.[9] [10]

Autonomous.jpg 

     Figure 2, Nautonomous

Another similar project was set up by the recycled Island Foundation. they make a sort of trial and place it on the coast of Rotterdam in strategic places and capture that way plastic. [11]

Environmental aspects

Work space of agents

In the North sea, there are some areas that cannot be traversed or are very busy with traffic. Along the coast of The Netherlands, there are areas that are protected by law. This is however mostly because of fisherman. That means that the agent will not be restricted, when it comes to those areas since it does not fish or harvest any other natural products. The problem that should be taken into account is the ship’s navigational routes. There are areas where there is a lot of boat traffic, especially at the ports. Along the coast, this is not an issue. (Appendix Environment)[12][13][14][15][16]

Waves and wind issues

When an agent is at sea it is not safe for the agent when there are high waves. It could break because it gets destroyed by a big wave. Looking at how waves are created, it is found that the wind is playing a big part in it. The harder and longer the wind blows, the bigger the waves will be. It is, therefore, hard to say when the agent should go back at a certain wind speed. However, some things can be determined, like at what wind speed it is dangerous and how big waves will get at a certain wind speed. For small boats, for example, canoes, it is recommended not to go on open sea if the wind speed is bigger or equal to 6Bft. Which means a medium wind. In table 2 is shown how high the waves will get at a certain wind speed. 


     Table 2, Influence wind on wave height

Wind.jpg

When the waves get higher than 1,7-2 meters it is too high for the agents. Before the agents will go on the water, the wind speed is measured. Also, while they are working the wind speed should be updated. This way the height of the current waves can be determined. When this calculation is done a decision can be made whether the agents should go to work or not. Also when they are working and the wind speed gets too high, it can be determined after how much time they should be called back to the coast. [17] [18]

Animals

Birds

An often overlooked problem are birds sitting on the boat. This is not convenient since a part of the boat might break or can get dirty. This problem is not hard to solve because there are some small tips and tricks that can prevent them from getting on a boat. For example, getting some netting and putting it above places they can land. Putting a fake crow on the boat or a string with cd’s attached to it will most likely scare the most of those birds away.

Fish

There are a lot of fish in the sea, which poses a problem. It would not be the intention to accidentally catch fish instead of garbage on the way. However, it is assumed, that the agents will make a certain noise and they won’t go too fast. This means the fish have plenty of time to see it coming and have enough time to get away.


Solution

Different concepts

During the project, a few different designs and possible solutions were created. These vary on a wide spectrum. Following are some of the concepts created.

The retrieval arm

The first design was to construct a boat with a number of arms on it to pick up each piece of garbage separately. While this would be a good option since it could grab pieces that are two to three meters deep. The programming of an arm is a whole project in and of itself. also, this design would make the boat too unstable when picking the garbage out of the water due to a large amount of mass moved. Nets on either side The second design was to make a boat with nets on either side that would rotate whenever a piece of garbage is caught. However, this could also, catch fish which is unwanted. Also, the design is not energy efficient because of the fact that it needs to move the nets in a rotational way which would consume a lot of energy.

Conveyor belts

The third design was to make a boat with conveyor belts to guide the garbage to a center flow area where they would be scooped up by another conveyor into a compartment. This design also was not very energy efficient. A lot of energy would be lost in moving the conveyors and the non-hydrodynamic design. It also could only pick up garbage that floats on the surface of the water.

Ramp to catch garbage

The final design was to make a boat with a ramp in the water. This way the garbage drifting two to three meters deep in the water can be pulled to the surface where they will be transported via conveyor belts on either side of the boat into a compartment for storage. This design will generate a lot of downwards force due to the giant ramp in the water, this can, however, be prevented by putting a floater or engine in the front to compensate for the downwards force.

Requirements, preferences and constraints

To make sure a good design is made there is a large list of RPCs constructed. These are split up into the following categories to make it easy to read:

Dimensions:

  • The boat needs to be 2 by 3 by 3 meters. This is so that the boat can still hold a lot of garbage. It also makes sure the boat is stable and it provides a large frontal area to pick up garbage.
  • The compartment needs to be 1.5 by 2 by 2 meters, this way it can carry a lot of garbage without having to be emptied.
  • The compartment needs to be separable in order to decrease downtime when emptying.
  • The clips holding the compartment in place need to be easily removable for easy separation when emptying.
  • The vehicle needs to have two floaters on each side (0.25 by 2 by 2.5 meters) in order to keep the boat floating in the water. Via Archimedes’ law, this means that the floaters will stay in the water for 80 percent with a full compartment.
  • The boat needs one ball-shaped floater (radius 0.6 meters) to compensate for downwards drag when moving through the water.
  • Space needs to be available for the conveyor belts on either side of the boat. These are needed to pull up the garbage once it is out of the water and transfer them to the compartment. This space would equate to 0.25 by 1 by 0.5 meters.
  • There must be a guiding slide to transfer the garbage pulled up by the conveyors. The space would equate to 0.25 by 1 by 0.2 meters.

Material:

  • The boat and the compartment are both made of polyester. This material is used in the construction of sailboats and is both strong and light.
  • The floaters need to be made of poly-ether since it is the most used material for floaters in general.
  • The whole vehicle and all of its parts need to be waterproof to prevent it from sinking. This can be done by using a coating over the polyester. According to the sources used this holds for about 25 years. [19] [20]

Transferring:

  • The vehicle needs to have a motor to move forward. In this project we have chosen for a ring motor, this motor should be strong enough for small boats up to 8 meters and therefore should be sufficient for our agent. [21]
  • It needs to have a fin located in the water to steer.
  • It needs to have a large enough battery in order to fill its compartment and return to a charging station.The battery life should be at least 12 hours, however, to determine the exact battery life the size of the agent, the speed of the agent, the engine distribution, the conveyor belts and the fin has to be looked at in more detail.

Sensors:

  • The vehicle needs to have a laser sensor in order to check if its compartment is full and needs to emptied. This laser gives the "full" signal when its trajectory is interrupted. However, this means that when the plastic is tossed into the container, it gives that signal. Therefore there need to be some kind of counter, which makes sure the signal gets send if and only if a certain time is past.
  • It needs a GPS system to locate its position and to make it back to the nearest pickup point when a storm is inbound.
  • The agent needs an inertial measurement unit in order to make sure it is still on the right path and the right speed when picking up garbage.[22]
  • It needs to have an internet connection to check the weather for conditions in which the agent should not be on the water and to communicate with the control station if there is a part that has broken down or the agent needs to be called back to a pickup point in event of an emergency situation.

Life-cycle:

  • The agent needs to keep working for 25 years, to minimize costs and to make sure it can keep cleaning the ocean, which unfortunately is never finished.

strategy

For the agents to gather plastics as efficiently as possible a gathering strategy has to be made. To cover the whole area, a strategy in which the agents move vertically would be a logical approach. When this strategy is used, it seems that almost all of the plastic on top of the surface of the water will be gathered. However, due to the fact that most of the plastics in the North sea are found at a depth of 1-3 meters, this strategy will not be sufficient enough. Therefore a new strategy has to be considered.

To gather the plastic that is 1-3 meters deep in the water, 2 slides are designed in front of the agent. These slides are 1-3 meters deep and push the plastics to the surface of the water. To stimulate this upwards thrust, the strategy will be adapted to the figure below:


Strategy.jpg 

     Figure 3, Strategy

In this strategy, the agent will navigate in the opposite direction of the current of the water. In this way, the plastics will collide to the slides and will be pushed due to the cooperation of the current and the speed of the agent. The best way to stimulate the thrust is to navigate the agents horizontally, parallel to the coast. However when the total area has to be covered there will be a lot of agents needed to gather all the plastics, therefore the strategy in the figure is the final strategy. In this strategy, the following are presumed. The area which the agents will clean has a width of Y meters and a height of X meter. When tides shift, the current reverse direction. The tides shift every six hours [23]. Furthermore, the average speed of the current is equal to 1.15 meters per second. According to the RPC’s the agents need to navigate with a speed of at least 3 meters per seconds, this means that in 6 hours an agent can travel a total amount of 64800 meters. To estimate the size of the area it will be presumed that the agent finishes n spikes at the total width of Y meters. De X and Y can be calculated by the following Equation 1: 

     Equation 1

64800=2n*√(x^2+(y/2n)^2 )

When the Y varies between 100 and 300 meters the height X can be calculated with the following Equation 2: 

     Equation 2

x= √((64800/2n)^2-(y/2n)^2 ) (2)

In the table below the different Y and X are shown, together with an approximation of n. 

     table 1, the size of the area.

Tab1.jpg

The X was estimated to be around 50 meters and therefore the size of the last row is chosen, with an approximate value of n.

Furthermore, there is assumed that at least 10 agents should be behind each other to gather plastics when the agents in front of them miss them. Furthermore, these extra agents are necessary to cover the area when the other agent is emptying its container.

In the model part, the optimal amount of agents and the optimal angle in which the agents gather the plastic in the area is chosen by simulating different agent numbers and different angles.

The question remaining now is where the agents have to be placed to clean up the North sea, while not being disturbed by boats, birds, sailors and so on. It is very difficult to take the birds that rest on the agents into account, therefore the focus lies on human disturb factors. According to the information provided in the environment chapter, the following locations are proposed:

Loc.jpg 

     Figure 4, Locations

These locations are based on tourist locations, harbors and places where rivers go into the sea. These locations are according to state of the art research the hot-spots where plastics goes into the North sea. As can be seen in the figure above, the direction shift of the currents is also taken into account by placing agents on both sides of the river.

Model

Model design in CAD

During the project two models were made, the first one functioned as a basis to make decisions upon, such as what sensors to use, pickup strategy and efficiency among others. The second model created is the final design, this design solved the practical problems and limitations that came up during the rest of the project.

the first design

The first thing that came to mind when designing the agent was the fact that it needs to pick up garbage efficiently. A lot of options came up in the initial designing phase. Arms to pick up the garbage, giant nets to trap garbage in etcetera. However these options were not efficient enough, it needed a lot of programming to move the different parts and a lot of energy would be lost in picking up something. So the decision was made to design an agent that could pick up garbage by moving through the water. The main inspiration for this was the nautonomous project and some concept designs made. [5] [24]

And so the first design was made, it uses conveyor belts on the outside to move the garbage horizontally towards the center in front of the agent and then uses a second conveyor to move it from the water in a compartment. The agent would be kept afloat using two floaters on either side and can move forward and steer using two motors at the end of each floater.

However, the first design had a few problems. First of the conveyor belts were fragile and would get a lot of pressure put on them when moving through the water against the flow. The outside conveyors were also held in place by relatively thin beams which would break easily. The second problem with the original design was the fact that the front area was big and was not hydrodynamic which would lead to a lot of water friction when moving. And lastly, most of the garbage which would be floating in the seas is up to two through three meters deep in the water. With all the limitations mentioned before, the agent would not be able to pick up all of the garbage. Since the friction forces would get too large when trying to get garbage out of the water.

Design1.jpg 

     Figure 5, First design

The second design

With all the limitations in mind, the second design was made. The new design picks up the garbage in the front and guides it to the surface without a large friction force. From there the blue conveyors will pick it up and guide it upwards. The conveyer belts will drop it off on the green panels which guide it further to the storage compartment. This way the design has fewer dangers in breaking, compared to the first design. It no longer has belts kept in place by thin beams, but a big front plate integrated into the front. The only conveyor belts left are located above water and therefore do not face such large forces as the first design. Secondly, the new design generates less friction due to the front plate and can pick up garbage which is located as deep as two to three meters. All together this will greatly reduce maintenance and power usage. And lastly, it has a compartment that is easy to be taken out and emptied.


Design2.jpg 

     Figure 6, Second design

Considerations for Cad model

Detecting Waste in the ocean

In this section, three types of agents will be defined. The first are agents that clean the ocean via brute force, this means they keep cleaning the same designated area over and over until they have run out of battery to the point their program tells them to move to a charging station. The second type is agents that use sensors to recognize the shape of plastic and other pollutions and move to the location to clean it up. After they’ve cleaned up the garbage they start scanning again. And lastly, the third type are agents that use ultrasound to scan the ocean for garbage and use the same cleaning procedure as agent prototype two. Below follows a description of the different types, good and bad aspects and both construction and operating cost.

Brute force option

Description

This prototype will have all the basic necessities, this means storage, motors, the ability to float on water, GPS and a mechanism for retrieving garbage from the ocean. Its way of working is via brute force: from the central communication center, it will get allocated to an area of the ocean. Once the agent arrives at its location it will start moving over the whole area, sweeping up every piece of garbage on its way. Once it is done it will start over again until the battery level hits a certain threshold or the compartment is full, after which it will make its way over to the charging station and get its compartment emptied as well.

Good and bad points

Good:

  • Simple design
  • When the path of cleaning is well designed, it should have few pieces of garbage seeping through its area
  • Compartments can be smaller due to the fact that more agents need to be used for cleaning

Bad:

  • Needs a lot more agents than the other two options due to the fact that it is using brute force instead of targeted cleaning, or the cleaning can take much longer than when using the other options
  • Even with good cleaning paths the garbage can get through
  • More agents means more charging options and more substitution agents to fill up the gaps from traveling agents, which can, in turn, cost more
Cost

The costs of this option will be the least of all the options listed. Due to the fact that this option uses only the features that are absolutely necessary for this agent. But the fact that more agents could be necessary (see above), the costs could go up.

Shape recognition option

Description

This prototype will have all the basic necessities as described in the previous prototype, but it will also be outfitted with a camera and shape recognition software. From the central communication center, it will get allocated to an area of the ocean. Once arrived it will start scanning the area for shapes it deems worthy of cleaning up. When it sees a shape it perceives as plastic, it will move over to the location and clean it up, storing it in the compartment. When done it will move on with scanning and the cycle will start over again until the battery level hits a certain threshold or the compartment is full, after which it will make its way over to the charging station and get its compartment emptied as well.

Good and bad points

Good:

  • Targeted cleaning means fewer agents than brute force cleaning
  • Fewer agents means less charging options and substitute agents which means lower construction and operation cost

Bad:

  • Technology is not yet advanced to the point that it is a feasible option due to the recognition range
  • Pixel distortion and image distortion can lead to recognition of non-existent garbage
  • In scanning and cleaning garbage can seep through if the software is not correctly calibrated.
  • Cameras have no depth perception when using a single camera since it only tracks pixel data and no distance
  • Some things that are garbage might not be received as such
cost

The costs of this option would rise severely owing to the fact that shape recognizing technology is fairly new to the market, and new technologies tend to cost more than technologies already longer existing. The implementing of this technology could also cause a rise in the costs. The size of the sensor would cause an increase in the dimensions and weight of the agent, among other things.

Ultrasound option

Description

This prototype will have all the basic necessities as described in the first prototype, but it will also be outfitted with an ultrasound device. From the central communication center, it will get allocated to an area of the ocean. When it gets there it will start scanning the ocean for pieces of plastic and other garbage. When it sees something it perceives as garbage the same procedure as the second prototype is initiated.

Good and bad points

Good:

  • Targeted cleaning means fewer agents than brute force cleaning
  • Fewer agents means less charging options and substitute agents which means lower construction and operation cost
  • Wide scanning area
  • Tracks depth
  • Can recognize garbage that is underwater

Bad:

  • Small objects might not be recognized, as they are seen as noise or get lost in continuous error and noise adjustments.
  • Maritime life can be seen as garbage and therefore cleaned up.
  • Presumably very sensitive to adjustments
  • Might have low accuracy compared to prototype two
Cost

The costs of this option will lie in between the costs of the other two options. The ultrasound technology has been on the market for a longer time, so it is further developed, and also cheaper and less than shape recognizing sensors. Another advantage is that waterproof ultrasound sensors already exist and could easily be bought. Ultrasound sensors sell at prices between $10 and $250. The scanning range has to be determined, in order to choose one type of ultrasound sensor, and with that its price.

Our choice

We chose the brute force option because the agents work in teams on different spots in the North Sea, which lowers the importance of picking up every piece of waste that passes the spot in which the agent works. If one piece passes one agent, another agent can pick it up. For this agent, there is no need to add the extra features mentioned above, and this will only increase the costs of the agent.

Picking up waste from the ocean

There are different options from which can be chosen regarding picking up waste from the ocean. A simple fishing net, a sort of arm with a basket attached to it, and a slide which would force the waste to the surface of the ocean, where it could be picked up by a conveyor belt, were all considered. Below, the different (dis-)advantages and costs of every option are discussed.

Fishing net

Description

This option would be about the same as the fishing nets used by the fishing industry (see Figure below), but smaller and used only two meters below the surface of the water.


Fishing.jpg 

     Figure 6, Fishing industry boat.
Good and bad points

Good

  • Can cover large patches of ocean
  • Many different net sizes to choose from
  • Many options for the size of the holes in the nets
  • Waste of all sizes can be picked up

Bad

  • Hard to determine the right size of the holes in the net, too large and waste may not be trapped, too small and other things than waste may be trapped in the net
  • Fish that swim close to the surface of the water could also be trapped by the net
  • How to empty the net into the onboard storage container without humans on board?
  • Takes up a lot of space
Cost

Recreational fishing nets aren’t that expensive, but when looking at more professional fishing nets, the costs can rise pretty quick, they can cost between 100 and 200 euros.

Arm with basket

Description

A visual representation of this option can be seen in the image below. A basket, with small holes (so the water doesn’t end up in the storage container), can move up and down around an axis, picking up waste objects.


Basket.jpg 

     Figure 6, Arm with basket agent.
Good and bad points

Good

  • Can pick up every piece of waste passing
  • The size of the basket can vary, so bigger waste objects can also be picked up

Bad

  • The friction force of the water causes the need of a strong motor or servo for turning the axis
  • What material is the basket made from? There could be the need of designing this from scratch, and this could cost a lot of time
  • If the basket is in the process of picking up a piece of waste, and another piece passes, it can’t pick up the other piece of waste, this is inefficient
  • All the electronics need to be at the back of the agent, which can cause the agent to be very heavy in the back and therefore unstable
Cost

Since this option will be needing a strong motor or servo, the costs can rise pretty quickly. Also, the material of the basket could be something that has to be designed from scratch, which can cost a lot of time and money. A simple fishing net could be used, of course, this could also solve the problem of the friction force of the water. But using a simple fishing net gives the problems mentioned in the section of the simple fishing net.

Slide with conveyor belt

Description

This option will use the upward force of water. On the front of the agent, a slide is made. When a waste object is in the path of the agent, it will bump against the slide, the slide will force the water and the waste object upwards (toward the surface of the ocean). When at the surface, a conveyor belt, made of plastic, with plastic spikes, will take over from the slide, and bring the plastic object further upwards until it falls into the storage container. The conveyor belt will have holes in it, so that the water, which has been forced upward, falls back into the ocean.

Good and bad points

Good

  • Every piece of waste in the path of the agent is picked up when using this method
  • Using forces outside the agent to pick up waste (water’s upward force)
  • All the agent has to do is sail its path and keep the conveyor belt running
  • No fish and other things than waste will be picked up using this method

Bad

  • All waste objects that aren’t in the agent’s path aren’t picked up
  • It may cost a lot of energy to keep the conveyor belt running all the time
Cost

The slide and the conveyor belt can both be made out of plastic, which just has to be shaped in a specific form. Since the form of a slide is used, the costs of a children’s slide are used as a base for the costs of the slide. These cost around 30 euros. For a plastic conveyor belt of 60 cm wide, a price of about 150 euros per meter has been found.[25]

Our choice

The choice fell on the slide option. One of the major advantages was the fact that no harm is done to marine wildlife when using this method. The goal is to clean up the ocean, not damage its ecosystem. Furthermore, the disadvantage concerning not picking up every piece of waste can be countered by the same argument used for the brute force navigational option: other agents can pick it up. The simplicity of the solution is also a plus, the agent does not need any extra sensors of knowing when to rotate (like with the basket). The extra costs for the slide and the conveyor belt are well spent if marine wildlife can be spared.

Netlogo model

In this part of the project, a model was made that simulates a certain amount of agents cleaning up an area of the North sea with a width of 300 meters and a length of 54 meters. The purpose of the model was to determine the optimal number of amount of agents by simulation. As said earlier in the chapter about the strategy, the velocity of the agents has to be at least 3 meters per seconds. In the model, this has become 4 meters per seconds because the chance of missing pieces of plastic is smaller. This is determined by simulating the model a few times.

The agents have to empty their container when their containers are full. In the total width of 300 meters, there are 6 stations, where the agents can empty their containers and refill their energy level. The initial energy is chosen very high, so the chance of getting the container full is greater than the chance of running out of energy. These stations are located at 25, 75, 125, 175, 225 and 275 meters. The charge time is estimated at around 8 ticks because the emptying the container will be executed as efficiently as possible.

The rest of the model can be seen by clicking on the link below:

https://drive.google.com/file/d/0B-QPPQg1oPoeOTNNUlpybFNkemc/view?usp=sharing

The result of the simulation with the respect to the number of agents are given in the tables located in the chapter data of model in the Appendix. When the date retrieved is taken into account the following can be concluded. According to the model 13 agent are needed with a agent distance of 2.5 meters. This means that 1,64 percent of plastics are missed.


Discussion

During the project, certain aspects of our progress could have been executed a lot better. Especially at the beginning of the project, the progress went very slow. We could not make decisions on what to focus on during the rest of the project, which resulted in a few shifts of our problem’s composition. When our problem was finally stated in a clear manner, we could finally focus on problem-solving, which resulted in the solution given in this report.

Another problem in our progress was the explanation of choices that we made with respect to the RPCs. Some choices were made by making assumptions, however, it was not clearly stated in our wiki at the time. Another set of choices were based on facts, however, lacked the sources needed. In short, we had to elaborate more on the choices we made, so the tutors could see why those choices were made validly. We have learned a lot about the importance of elaboration of choices and it also led to discussions that have improved our project in the end.

In the group, we had sometimes trouble with meeting up and finding time to work on the project as a group. If we had more time, then we would be exploring more options for strategies and optimizing it more.

In this project, we could have benefited by making a more structural planning because now the state of the art research went slowly. We should have contacted the different organizations earlier in the project. The contact we made with the organizations provided information which we used in the problem-solving part of the project.

If we had contacted them earlier in the project, we could have found a solution much earlier, which would have resulted in more time for optimization and model making.

Conclusion

The goal of our project was to make sure that waste located in the North Sea doesn’t move to the gyres in the open ocean. To do this, we decided that an ocean cleaning agent needed to be designed to sail the North Sea and collect the waste floating there. We started out with researching the state-of-the-art of this subject. This included literature research and contacting organizations which might know more about this subject. Using the information gathered from this research we started the design of the agent. The most important choices were the navigational strategy and the method of picking up the plastic because only then a model for the agent could be made, and a NetLogo environment could be created.

The goal of the agent was to pick up as much waste, if not everything, as possible. A strategy has been developed to reach this goal. The strategy that has been developed, which is stated in the report, has been tested in NetLogo and it only misses 1,64 percent of the waste. This efficiency is accomplished when 13 agents, with a distance of 2,5 meters between them, are working. The workspace has a width of 300 meters and a length of 54 meters. We consider this a strategy that works very well.

Though our agent does pick up most of the plastic it encounters, and when working in teams, 98,36 percent of the plastic is picked up, the North Sea will never be totally clean if dumping of waste into the ocean doesn’t stop. If the dumping keeps going, the ocean will still be polluted with waste, and our agent would need to work forever. In the scenario where the dumping of waste into the ocean stops, our next focus could be to clean up the gyres in the ocean. The ultimate goal is, of course, to make sure that there is no waste at all in the oceans, but we still have a long road ahead before this could ever be achieved.


Appendix

Garbage distribution

Before the designing of the agent can start an impression of where our target, the garbage, is located is needed. After contacting several organizations a proper estimation could be made of how the garbage is disturbed in the North sea.

At first the depth of the garbage will be elaborated. Research has shown that in a water column of 5 meters, starting at the surface, 80% of it can be found in the top 2 to 3 meters [26] . However, these numbers follow from measurements done in the North Atlantic Gyre, so do they also hold for the situation in the North sea? Without going too much in scientific detail, we will try to explain if the North Atlantic ocean is comparable with the North sea. An object floats if it has a smaller density than the liquid. Density is a ratio of mass and volume and since these quantities are the same in both situations we can assume the results of the study are also applicable for the North sea.

The second variable is the distance of the plastic to the coast. Since we couldn’t find any reports with the necessary data we contacted Rijkswaterstaat. It turned out there isn’t any specific data, but the rule-of-thumb is; the further away from the coast, the smaller and less dense the garbage gets. Combining this information with the location of the hot-spots (outlet of rivers, harbors and beaches), only a few potential locations remain.

data of model

     Table 3, Dataset 1

Data1.jpg 


     Table 4, Dataset 2

Data2.jpg 


     Table 5, Dataset 3

Data3.jpg

Environment

Coast1.jpg 

     Figure 7, Fishing areas North sea[14].

Coast2.jpg 

     Figure 8, Shipping routes North sea[27].

References

  1. ↑ http://www.plasticsoupfoundation.org/feiten/gevolgen-voor-het-milieu/
  2. ↑ http://www.plasticsoupfoundation.org/feiten/gezondheidseffecten/
  3. ↑ http://www.icgrevelingen.nl/blog/2016/01/14/cleanriverproject/
  4. ↑ https://www.theoceancleanup.com/
  5. ↑ 5.0 5.1 http://www.tedxdelft.nl/2012/10/tedxdelft-first-performer-boyan-slat/
  6. ↑ https://plasticsoepsite.wordpress.com/onstaan-plasticsoep/
  7. ↑ https://www.theoceancleanup.com/technology/
  8. ↑ http://www.wur.nl/nl/Dossiers/dossier/Plastic-afval-in-zee.htm
  9. ↑ https://www.youtube.com/watch?v=BYXlv8fgj80&feature=youtu.be
  10. ↑ https://www.waternet.nl/blog/de-nautonomous-automatisch-drijfvuil-vissen/
  11. ↑ http://www.recycledisland.com/
  12. ↑ https://www.noordzeeloket.nl/functies-en-gebruik/natuur_en_biodiversiteit/
  13. ↑ https://www.noordzeeloket.nl/functies-en-gebruik/scheepvaart/
  14. ↑ 14.0 14.1 https://www.noordzeeloket.nl/images/Bodemberoerende%20visserij%20op%20de%20Noordzee%20-%20Huidige%20situatie,%20recente%20ontwikkelingen%20en%20toekomstscenario%E2%80%99s_4125.pdf/
  15. ↑ http://www.rwsnatura2000.nl/default.aspx/
  16. ↑ https://www.noordzee.nl/
  17. ↑ http://www.wadkanovaren.nl/hetwadfysiek.html
  18. ↑ http://www.wadkanovaren.nl/veiligheid.html
  19. ↑ http://www.bootschilderen.nl/polyester/
  20. ↑ https://polyestershoppen.nl/polyester/topcoat-transparant-66.html
  21. ↑ http://www.destilleboot.nl/torque-jet-voor-g2/517/p111/c108/default.html
  22. ↑ https://en.wikipedia.org/wiki/Inertial_measurement_unit#frbanner3
  23. ↑ http://www.ebvloedgetijde.nl/
  24. ↑ https://www.waternet.nl/blog/de-nautonomous-automatisch-drijfvuil-vissen/
  25. ↑ http://www.safeconveyor.com/Modular-Plastic-Conveyor-Belting-Pricing.php
  26. ↑ The vertical distribution of buoyant plastics at sea: an observational study in the North Atlantic Gyre – J. Reisser, B. Slat, K. Noble, K. du Plessis, M. Epp, M. Proietti, J. de Sonneville, T. Becker and C. Pattiaratchi
  27. ↑ https://www.noordzeeloket.nl/images/20141111_1410-0334-004_Scheepvaart_d02_1202.pdf
Retrieved from "https://dsdwiki.wtb.tue.nl/index.php?title=PRE2016_3_Groep5&oldid=39062"