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===The choice=== | ===The choice=== | ||
'''Effectivity''' | '''Effectivity''' | ||
The walking robot travels at the speed of a pedestrian. In this way, delivery takes a very long time, certainly in larger areas. The side walk cart is not much faster. Looking at the other options, the walking robot and the side cart are not what we are aiming for. However, these systems might work very good in small urban areas with a dense population. The road cart is similar to the current system, which we want to improve. They are effective in both rural and urban areas and there are already systems available for doing this autonomous. The helicopter is a very effective option, because it is capable of flying over obstacles and it is not using roads. The helicopter is suited for all kinds of environments and they are very fast. However, the package weight might be a big limitation. A plane would be a faster way to deliver packages, the packages could be heavier than in a helicopter, and like the helicopter, the plane ignores roads and other obstacles. One major disadvantage of using a plane, however, is that it needs a landing strip. The last option is the zeppelin, which is a very safe way to deliver packages. It doesn’t crash like helicopters and planes do. In addition, it can carry very heavy packages and consumes very little power. | The walking robot travels at the speed of a pedestrian. In this way, delivery takes a very long time, certainly in larger areas. The side walk cart is not much faster. Looking at the other options, the walking robot and the side cart are not what we are aiming for. However, these systems might work very good in small urban areas with a dense population. The road cart is similar to the current system, which we want to improve. They are effective in both rural and urban areas and there are already systems available for doing this autonomous. The helicopter is a very effective option, because it is capable of flying over obstacles and it is not using roads. The helicopter is suited for all kinds of environments and they are very fast. However, the package weight might be a big limitation. A plane would be a faster way to deliver packages, the packages could be heavier than in a helicopter, and like the helicopter, the plane ignores roads and other obstacles. One major disadvantage of using a plane, however, is that it needs a landing strip. The last option is the zeppelin, which is a very safe way to deliver packages. It doesn’t crash like helicopters and planes do. In addition, it can carry very heavy packages and consumes very little power. | ||
'''Reliability''' | '''Reliability''' | ||
The zeppelin might seem as a very nice option, but it is a very slow system. On top of that, it is a very big object, which can be easily hit by other objects. Also landing is complex and the light weight of it is a drawback, because it is very dependent on the weather. The sidewalk cart, on the other hand, is very reliable, because there is little chance that the package will be damaged. However, when the robot gets stuck, it will not be capable of getting free by itself, which will cost a lot of time. The same holds for the walking robot; the package is safe, but if something happens, it will take a lot of time. | The zeppelin might seem as a very nice option, but it is a very slow system. On top of that, it is a very big object, which can be easily hit by other objects. Also landing is complex and the light weight of it is a drawback, because it is very dependent on the weather. The sidewalk cart, on the other hand, is very reliable, because there is little chance that the package will be damaged. However, when the robot gets stuck, it will not be capable of getting free by itself, which will cost a lot of time. The same holds for the walking robot; the package is safe, but if something happens, it will take a lot of time. | ||
Speed and accuracy are in favor of a plane or a helicopter, but planes and helicopters are very dependent on the weather. There are solutions for this, but this will impact the flight time and the consumption of the systems. | Speed and accuracy are in favor of a plane or a helicopter, but planes and helicopters are very dependent on the weather. There are solutions for this, but this will impact the flight time and the consumption of the systems. | ||
'''Safety and privacy''' | '''Safety and privacy''' | ||
The chance of getting into a collision is not very high for a helicopter or a plane, but when they do, the damage probably is big, and might lead to dangerous situations. However, there are several backup systems possible, so that the helicopter and plane will still be able to fly or land safely in case of one or two malfunctions. For the walking robot, a collision is also very unlikely. The only problem might be people or vehicles bumping into the robot and crossing roads. The same holds for the side walk cart. For both autonomous systems, however, there are programs to safely cross the road. These programs can also be implemented in the road cart. For instance, Tesla and Google car drive autonomously with such a program. The zeppelin, as described before, is a very safe way of travelling. A big drawback is that the vehicle is very big, so it can be hit by objects very quickly. | The chance of getting into a collision is not very high for a helicopter or a plane, but when they do, the damage probably is big, and might lead to dangerous situations. However, there are several backup systems possible, so that the helicopter and plane will still be able to fly or land safely in case of one or two malfunctions. For the walking robot, a collision is also very unlikely. The only problem might be people or vehicles bumping into the robot and crossing roads. The same holds for the side walk cart. For both autonomous systems, however, there are programs to safely cross the road. These programs can also be implemented in the road cart. For instance, Tesla and Google car drive autonomously with such a program. The zeppelin, as described before, is a very safe way of travelling. A big drawback is that the vehicle is very big, so it can be hit by objects very quickly. | ||
Protection of the system and the package | Protection of the system and the package | ||
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'''Costs''' | '''Costs''' | ||
The costs for all options depend on assumptions, should it be water resistant? How many safety precautions should be added? How many and what kind of sensors should be used? The plane, however, needs extra protective packaging materials, which will increase the costs per delivery. For the walking robot and the sidewalk cart, many disposal stations will be required, which will increase the costs for these options. The costs for the road cart may also be somewhat higher, because of the technology needed to safely deliver packages and to make sure the right package is delivered at the right house. | The costs for all options depend on assumptions, should it be water resistant? How many safety precautions should be added? How many and what kind of sensors should be used? The plane, however, needs extra protective packaging materials, which will increase the costs per delivery. For the walking robot and the sidewalk cart, many disposal stations will be required, which will increase the costs for these options. The costs for the road cart may also be somewhat higher, because of the technology needed to safely deliver packages and to make sure the right package is delivered at the right house. | ||
'''The choice''' | '''The choice''' | ||
We chose the helicopter as the delivery system that is most likely to be implemented in real life. The helicopter is compact, it is capable of landing almost everywhere. Compared to the other options, it is not necessarily more evironmentally friendly. However, it is at least more environmentally friendly than the delivery system right now, with vans and cars. On top of that, it is certainly the most efficient option. The air is rarely used except for airplanes, but those fly much higher than helicopters. Therefore, we think helicopters are an exceptional new way of delivering packages to regular customers. In addition, they are the second most fast option. Only the plane is faster, but there are a lot of drawbacks in using a plane in a delivery system. To finish, it is relatively cheap. The initial costs are quite high, however, further on, there will be almost no additional costs. | We chose the helicopter as the delivery system that is most likely to be implemented in real life. The helicopter is compact, it is capable of landing almost everywhere. Compared to the other options, it is not necessarily more evironmentally friendly. However, it is at least more environmentally friendly than the delivery system right now, with vans and cars. On top of that, it is certainly the most efficient option. The air is rarely used except for airplanes, but those fly much higher than helicopters. Therefore, we think helicopters are an exceptional new way of delivering packages to regular customers. In addition, they are the second most fast option. Only the plane is faster, but there are a lot of drawbacks in using a plane in a delivery system. To finish, it is relatively cheap. The initial costs are quite high, however, further on, there will be almost no additional costs. | ||
Revision as of 14:47, 23 March 2017
Group members
Lotte Aerssen - 0892039
Wouter van den Bemd - 0948482
Lennard Kerkhoven - 0955882
Bjorn Walk - 0964797
Wouter Weekers - 0956095
Noud Schoenmakers - 0938197
Introduction
The current delivery systems that are available in the Netherlands are failing to deliver. There are three reasons that show it has to be changed. First the delivery times are too long, people and small businesses rely to receive their packages as soon as possible. However, because of dense traffic and crowded streets the orders take too long. Also in the ever changing society of today people are not bound to one location anymore. The society is craving for a system that delivers their packages on-the-go. Finally the the companies only deliver in a given time frame, thus the costumer needs to stay home if he wants to receive the package. This even fails because of the systems that are used by the companies where emails and apps fail to deliver.
These reasons show that the delivery system is in need of innovation. This report will elaborate the options on how to do so. Then one of the options will be chosen after an elaborate research and carefully taking the user in consideration.
User needs
In the ever changing environment of today, the customer and small businesses rely on the postal service’s fast delivery traject. However the future will need a faster, more reliable and more user centered traject of postal delivery. Therefore we want to develop a system that brings postal packages faster to the customers and does this in a diverse way where it will even be possible to order AND receive packages on-the-go. Thus it will not only be faster and more reliable, it will bring the user(customer) back to the center again with a system that introduces a complete new approach to the world of postal service delivery.
Approach
One of the goals of our system is that it tackles problems with regard to urban and countryside delivery of packages. This could feature a two way system. For instance, when the package needs to go to an urban environment, it could be delivered using autonomous busses. The delivery to the countryside could be done using aerial vehicles such as drones, airplanes, balloons etc.
Therefore the project will focus and investigate multiple possibilities of postal delivery services and it will not just focus on, for example, drones because there are numerous possibilities regarding the approach of autonomous postal delivery services.
Further, it is important that there is a possibility to grow for this project. For example, when designing a system that could be used for urban environments. One of the solutions could be a massive tubing system. This could make the delivery of postal services fast. However the we want a system that is designed for the user and around the environment of the user. Thus the city should not be designed around the system, the system should be designed for the city. This is an important issue since one of the goals is to make a system that has the ability to grow. Therefore it is important that it is diverse and impliable in every environment so that it could be possible to grow from city scale to a world wide system.
Boundary conditions
Some important boundary conditions are:
- safety
- weather resistance
- speed
- diversity
- sustainability
Ideas
The creation of a system with 'on-the-go' availability a system with a portable landing site could be used. To reach the customer when he is at the camping for instance, a portable landing site could be used for instance, such as the image below.
Deliverables
This research should result in a recommendation or advice on which delivery system to use based on the following five criteria:
- Effectivity
- Reliability
- Safety and privacy
- Protection of the package
- Costs
Furthermore it should describe how this system finds the right location and delivers the package.
After the first research it was concluded that the helicopter drone was the best option (see chapter: Options). The recommendation should thus explain how the drone should land and deliver a package at a customer’s location.
To be able to give good advise conclusions have to be made about the following:
- The landing mechanism, how does the drone have contact with the ground? Will the drone land or should the package just land with for example a parachute? A complete concept of what kind of mechanisms the drone should have to land a package at the desired location should be made.
- Where to land, what are safe landing locations and what rules are necessary to let a drone land at important locations? A good description of how the drone finds its landing location will be made.
- Error protocol, what does the protocol look like that the drone follows if the customer is unable to receive the package? What actors are/should be involved in this protocol? A protocol of what has to happen when the package cannot be delivered will be made.
In addition to the second point above an experiment will be done to verify that the option for finding the landing position which looks the best on paper is indeed a viable option.
Options
There are a few options on how to design such a system. First, the system could go over land or by air. Both bring an their own drawbacks but also their benefits to the problem.
Differences between rural and urban areas
Urban and country delivery systems need a different approach when it comes to autonomous package delivery. Urban zones are high populated areas which contain many buildings which can be tall. Urban zones are usually located in cities or towns and contain many roads. Country areas are very different to urban zones because they have a low population density with fewer but longer roads of which some may be unpaved. High buildings are less likely in country areas but trees are more common.
Delivery system for rural areas
Delivery systems in rural areas preferably have a high travel speed as great distances are common. High speed wheeled robots that travel on the road and flying robots meet these requirements. Flying robots are preferable since they do not need advanced hardware to deal with other traffic. Another downside of wheeled robots is that the technology to take place in traffic is also not fully developed. Flying robots can travel easily over the often low buildings and trees in rural areas with a very low chance of having a dangerous crash with a person.
Delivery system for urban areas
In urban areas, a way to travel is preferred where the complexity of the environment does not affect the robot too much. Safety is also an issue, since it is a highly populated area. Slow moving robots are preferred because this makes collisions less dangerous. Legged robots or wheeled robots which travel on the sidewalk are perfect for this environment. Low travel speeds do not matter since travel distances are usually small in urban areas. The sidewalk is a relatively simple environment, which makes movement easier. Flying robots and high speed wheeled robots are not safe enough because the complexity on the road or in the air between the tall buildings makes it likely to crash, which is rather dangerous for such high speed systems.
Options for delivery
There are many different methods to move from point A to point B. One obvious method is by using wheels. Robots on wheels are well developed but they require pavement to function reliably and they cannot handle stairs. Travel speeds of wheeled robots are usually slow if they travel on the sidewalk where high speed motorized vehicles are not allowed. Driving on the road allows higher speeds, but the robot has to be equipped with more advanced hardware, thus raising the price. Another way to move is by using propellers to fly, which can be very fast. Important disadvantages are that packages cannot be very heavy, tall buildings have to be avoided and a crash in a populated area can be dangerous. Finally legs can be used to move from one location to another. At the moment legs are one of the most challenging ways to move around as a robot, since balancing on different surfaces can be quite a challenge. This way of movement is similar to the robots on wheels. The main difference is that a robot with legs can walk stairs and is less likely to get stuck on unpaved roads.
Helicopter
The helicopter is an airborne vehicle which can carry a package. This particular option has a lot in common with the system used by Amazon Prime air. This small and lightweight vehicle type can only carry relatively light loads, as weight has a strong impact on battery life. It usually travels very fast at a certain altitude. In case of Amazon Prime Air this height will be 100 meters and the speed will be up to 80 km/h. The drone will carry the package in a safe, which can only be opened by the authorized person using his or her smartphone.
Effectivity
As helicopters are not affected by the quality or presence of roads they can be used in both urban and rural areas, making them very diverse and suited for all kind of environments. Package delivery requires a place to land, which renders it useless at locations without a proper landing spot. However, the spots do not have to be big, as the vehicle itself is small. The helicopter is also very effective at places with a bad infrastructure, because it can fly over obstacles. They also travel very fast and always travel the shortest route, which gives the fastest delivery time besides the plane compared to the other options. Maximum package size and weight is somewhat limited, since a helicopter has to constantly fight gravity and increasing the weight will increase the load. The range of a helicopter is also limited, as flying uses a lot of battery power and big battery packs can not be used due to weight.
Reliability
Helicopters are heavily dependent on the weather. Fast winds, pouring rain and snow all affect the helicopter. Of course there are modifications available to make a helicopter waterproof or increase the strength of the motor, but this also increases the weight and therefore decreases flight time and increases the power consumption of a helicopter.
Safety and privacy
Overall, the chance of a collision and a person or property, is very small for a helicopter. This is because it travels in the open air, with almost no obstacles to collide with. However, in the event of a crash, a helicopter will drop from a high altitude, which could be a very dangerous situation. This can be prevented by applying several backup systems in such a helicopter, so it can for example still fly with one or two malfunctioning motors. On the subject of privacy, the drone will need cameras and sensors to land at a certain position. This could violate privacy, however, if the images are automatically interpreted and deleted by the helicopter afterwards, it will not influence privacy at all.
Protection of the package
The fact that this option is airborne means that it has less risk of being damaged assuming there are traffic rules for drones. Its altitude ensures that the system can not be abused by a third party. The only moment where it is vulnerable is at the delivery point. Therefore it should not stay long at the delivery point, even though it has a protected safe.
Costs
The price of such a system is heavily dependent on the assumptions. Making a helicopter water resistant or adding more safety precautions may increase the price of the system.
Plane
A package delivering plane will generally travel very fast, as this is required to generate enough lift for the plane to carry the package. This vehicle can only carry lightweight packages, as weight has a strong impact on the battery life. This vehicle will travel at an altitude of about 100 meters, which is the same altitude as Amazon Prime Air. Typical speeds for radio controlled aircraft are between 120 and 180 km/h. Dropping the packages will require parachutes and a certain drop off location.
Effectivity
This option is definitely the option with the fastest delivery time. With the highest travel speed of all options and the fact that it can fly straight to the target, the plane will be able to deliver a package within minutes. The maximum package size is somewhat limited, as extra weight makes the flight time lower. The fact that it ignores waters, roads and other obstacles, makes the plane useful in areas that cannot always easily be reached.
Reliability
Planes are dependent on the weather. Fast winds, pouring rain and snow all affect the helicopter. Of course there are modifications available to make a plane waterproof or increase the strength of the motor, but this also increases the weight and therefore the flight time decreases and the power consumption increases.
Safety and privacy
Airborne vehicles have only small chances of collisions in air, which can be avoided with air traffic laws. One problem with planes is that they cannot stop flying when needed. Helicopters for example can slow down and then slowly decrease its altitude until it touches the ground. Planes need a runway to stop, which might become a problem above urban areas. Crashing of a plane can be severe due to the high speed and altitude at which it travels. Planes will also need multiple sensor to calculate how to drop off a package. This may offend privacy if the images are not immediately deleted.
Protection of the package
A plane will need to land on a landing strip if it wants to deliverDelivering a package will require dropping it from the plane,. Packages will have a parachute attached to it and they will be packed in protective wraps, which will ensure a safe landing for the package. A problem with this is that there is no good way to prevent unauthorized persons to grab the package, as the person cannot authenticate with his or her mobile phone while the plane is midair.
Costs
The costs of such a plane is heavily dependent, adding modifications can cost a lot of money but may increase reliability. One side effect of the plane is that protective packaging materials will be used, which will increase the costs per delivery.
Walking robot
This robot uses legs to move on the sidewalk from point A to point B. It uses sensors to avoid collisions with obstacles or persons and it can use GPS service to move itself towards the destination. This type of robot is very similar to the already built Cassie robot. Using legs instead of wheels allow the robot to walk on stairs and decreases the chance to get stuck on bumps on the sidewalk compared to wheels. The movement speed of the robot will be about the movement speed of an average pedestrian.
Effectivity
Delivering packages at the speed of an average pedestrian takes a very long time. Therefore the robot is only effective in a small range around the package disposal station. For covering large areas, a lot of disposal stations have to be placed and these also have to be supplied with goods. This is fine for small systems where only one disposal station is required, for example a pizza delivery service. The products will then be produced and disposed at the same location. This removes the struggle of filling the right disposal stations with the right products which makes the process much more slow because of the extra step in the transport process and therefore less effective. A system like this would only work well for small areas with a dense population. It can be concluded that the system will be effective in urban areas for local companies and less effective or even obsolete for greater delivery areas or a rural area with a low population density.
Reliability
Reliability is an important factor for a delivery system. Small delivery robots can be very reliable under the right conditions which leads to a trustworthy delivery system. Walking robots are unlikely to damage the package. This is because they move very slow and store the packages in a safe inside the robot, which in the uncommon event of a collision prevents damage to the package. In an event of hardware failure, the robot will also be rather safe, as the robot moves very slowly. The central station will be notified since the robot does not move. A repair mechanic can be send towards the robot to fix it, which causes a slight delay in delivery time but no damage to the package.
Safety and privacy
A walking robot only participates in a few ways in traffic. First of all it must be able to safely walk on the sidewalk using its sensors to avoid obstacles and humans or pets. A collision with a person will be very unlikely because distance sensors can check whether there is an object in from of them and then automatically stop moving. Therefore the only real threat is a human or vehicle which bumps into the robot, which can be more dangerous. Also, the robot must be able to cross a road, which is more complex than walking on the sidewalk, as it has to recognize whether it is safe to cross, taking different traffic into account and their different roles and speeds. This can become quite challenging but autonomous cars by Google have proven that autonomous driving is possible. This also includes an extensive monitoring system which can determine where every traffic participant around the vehicle is located and which speed it has.
Protection of the system and the package
A walking robot will be a very vulnerable robot, as it moves slowly and it is not that heavy due to its maximum size. The robot will need some sort of package protection safe which can be opened using NFC on the smartphone of the customer. To prevent stealing the vehicle as a whole, anti-theft features should be implemented. This can be done by using the tracker that is already in the robot, or by using a loud alarm which goes off once the robot is lifted up or damaged. This should also immediately send a warning message to the staff of the delivery system who can warn the police if it is necessary.
Costs
The costs of such a vehicle might be high, as it needs many sensors to observe its environment. Out of all these sensors the visual sensors are the most expensive as it needs both the cameras and computational power to process the images and locate all the obstacles. Also, the fact that many disposal stations will be required makes this system even more expensive.
Sidewalk Cart
This vehicle moves packages from point A to point B using the sidewalk. It has various sensors to avoid collisions with obstacles or persons and it is able to use GPS to move itself towards the destination using wheels. The packages these robots can carry can be quite heavy, however, the volume of a packet will be limited. This is because the robot has to be able to avoid obstacles on the sidewalk, which cannot be done if the dimensions of the cart including the package are too big. The movement speed of the robot will be about the movement speed of an average pedestrian.
Effectivity
A small delivery unit that travels at the speed of an average pedestrian which is about 5 kilometers an hour is very slow. This makes the robot only effective in a small range around the package disposal station. For covering large areas, a lot of disposal stations have to be placed and these disposal stations also have to be supplied with goods. This is fine for small systems where only one disposal station is required, for example a pizza delivery service. The products will then be produced and disposed at the same location. This removes the struggle of filling the right disposal stations with the right products which makes the process much more slow because of the extra step in the transport process and therefore less effective. A system like this would only work well for small areas with a dense population. There can be concluded that the system will be effective in urban areas for local companies and less effective or even obsolete for greater delivery areas or a rural area with a low population density.
Reliability
Reliability is an important factor for a delivery system. Small delivery robots can be very reliable under the right conditions which leads to a trustworthy delivery system. Sidewalk carts are very unlikely to damage the package. This is because it moves very slow and stores the packages in a safe inside the cart, which in the uncommon event of an collision prevents damage to the package. The robot however has a chance to get stuck by for example driving on uneven terrain. The robot will be able to notice that it is stuck and send a warning to the central station, where a human controller can try to unstuck the robot. In an event of hardware failure, the robot will also be rather safe, as the robot moves very slowly. The central station will be notified since the robot does not move. A repair mechanic can be send towards the robot to fix it, which causes a slight delay in delivery time but no damage to the package
Safety in traffic
A sidewalk cart only participates in a few ways in traffic. First of all it must be able to safely walk on the sidewalk using its sensors to avoid obstacles and humans or pets. A collision with a person will be very unlikely because distance sensors can check whether there is an object in from of them and then automatically stop moving. Therefore the only real threat is a human or vehicle which bumps into the cart, which can be more dangerous. Also, the robot must be able to cross a road, which is more complex than walking on the sidewalk, as it has to recognize whether it is safe to cross, taking different traffic into account and their different roles and speeds. This can become quite challenging but autonomous cars by Google have proven that autonomous driving is possible. This also includes an extensive monitoring system which can determine where every traffic participant around the vehicle is located and which speed it has. The question however is how much a sidewalk cart can monitor as it is such a small vehicle.
Protection of system and the package
Stealing packages, destroying the equipment or stealing the robot as a whole are all forms of abuse. A sidewalk cart will be a very vulnerable vehicle, as it moves slowly and it is not that heavy due to its maximum size. The robot will need some sort of package protection safe which can be opened using NFC on the smartphone of the customer. To prevent stealing the vehicle as a whole, anti-theft features should be implemented. This can be done by using the tracker that is already in the robot, or by using a loud alarm which goes off once the robot is lifted up or damaged. This should also immediately send a warning message to the staff of the delivery system who can warn the police if it is necessary.
Costs
The costs of such a vehicle might be high, as it needs many sensors to observe its environment. Out of all these sensors the visual sensor are the most expensive as it needs both the cameras and computational power to process the images and locate all the obstacles. Also, the fact that many disposal stations will be required makes this system even more expensive.
Road cart
This vehicle delivers packages by traveling over the normal roads cars use. Because of this the road carts are much like the delivery vans that are used today. However there are a few differences to make it an autonomous delivery system. Firstly it drives completely autonomous. To make this possible it has to have a lot of sensors, GPS and AI to make decisions. Secondly the unloading of the package is also done autonomously. Due to its large storage area the road cart can carry large and heavy items. The road cart can travel at the same speeds as normal delivery vans can.
Effectivity
As said before the road cart is basically like the vans used today. This makes them effective in a large range, because they can travel at high speeds. Also the large storage space the vans have makes it possible to take a lot of packages in one run. This however introduces another difficulty namely the one of taking the right package at the right location. However there are already systems that can do this, making the road cart an option for both rural and urban areas.
Reliability
To be reliable the delivery vehicle has to be able to deliver the package safely and on the scheduled time at its destination. Road carts travel by the roads between the normal traffic. This makes its arrival times uncertain as there are a lot of things that can delay the vehicle, such as traffic jams or crashes. Another problem is possible damage to the packages. Because the storage room of the vehicle is large there is a lot of room for the package to move around when taking turns or crashing if it is not tightened secure enough causing possible damage to it. Also, when having either a software or a hardware failure the autonomous cart can become a dangerous projectile as it can travel at high speeds making safety an issue.
Safety in traffic
The road cart participates in the busy traffic on the roads. Therefore it has to have sensors to prevent collision. This technology is already used by for example Tesla for the autopilot function, so this should not be a problem. The only problem is thus when another vehicle crashes into the cart, but this is a problem all vehicles on the road face so there is no reason this should be the reason not to choose this option compared to the vans used today.
Protection of the system and the package
A road cart will not be very vulnerable to abuse, because it will most likely be the size of a normal delivery vehicle so it cannot be picked up like for example the sidewalk cart. The road cart can also be locked automatically when no package is getting dropped off. So abuse of the road cart will not be a big problem.
Costs
The costs of the road cart might be very high as it needs a lot of technology to make sure the package gets delivered safely, but with the rapid growth of technology these techniques will get cheaper.
The zeppelin
One of the options is to make the system by using a zeppelin. It will take the packages from A to B through the air. It will use GPS to know its location and use some sort of engine to propel itself through the sky.
Effectivity
A zeppelin can easily be adjusted to have a high lift force. Using a large balloon with a lightweight gas e.g. helium makes it possible to lift heavy objects. It could therefore be used to easily lift packages of 2 kilograms, while they might even be able to lift up to 5 kilograms or more. This is a big difference with other aerial options. Also the power usage is much lower on a zeppelin, as the balloon passively compensates for the gravity caused by the package. The delivery speed of such a system is rather low as zeppelins move slowly through the air, which is mainly due to their large frontal area which causes a high air resistance. As an aerial vehicle it is able to fly directly to the destination, which is an advantage over ground vehicles. However, its size can make landing difficult.
Reliability
As zeppelins are large lightweight flying vehicles, they are easily disturbed by the weather. Differences in temperature can cause the gasses in the balloon to expand or compress, which will affect the lifting performance of the vehicle. Another issue is wind due to the large size of the vehicle. Winds can easily sweep away a zeppelin, as the large surface catches much wind and its low mass makes it extra vulnerable.
Safety in traffic
When a zeppelins balloon is pierced and the gas flows out of the balloon, it drifts towards the ground on a slowly. Therefore, in an event of hardware failure, the possible damage of such a system would be much less compared to other aerial vehicles. However, due to its size it could become a big obstacle. If for instance a zeppelin lands on a highway, the balloon could be very dangerous because it could cover the view of a driver, which leads to a crash. Also several sensors will be required to percept its environment. One important sensor is a camera to allow it to detect where to land. This may violate privacy, as the camera may be able to record private property.
Protection of the system and the package
As the zeppelin flies in the air, the package is relatively safe. Due to their slow speed and soft landings in case of hardware failure, it is very unlikely that the vehicle itself will damage the package. Also a safe will be added which prevents unauthorized persons from receiving the package from the zeppelin.
Costs
The costs of a zeppelin will be around the same as the other aerial vehicles. While the motors and the battery can be smaller and cheaper, the balloon increases the price. This is mainly due to refilling with helium due to leakage and the extra maintenance costs as the balloon should be checked on leaks, which is more time consuming then replacing a motor when its malfunctioning.
The choice
Effectivity
The walking robot travels at the speed of a pedestrian. In this way, delivery takes a very long time, certainly in larger areas. The side walk cart is not much faster. Looking at the other options, the walking robot and the side cart are not what we are aiming for. However, these systems might work very good in small urban areas with a dense population. The road cart is similar to the current system, which we want to improve. They are effective in both rural and urban areas and there are already systems available for doing this autonomous. The helicopter is a very effective option, because it is capable of flying over obstacles and it is not using roads. The helicopter is suited for all kinds of environments and they are very fast. However, the package weight might be a big limitation. A plane would be a faster way to deliver packages, the packages could be heavier than in a helicopter, and like the helicopter, the plane ignores roads and other obstacles. One major disadvantage of using a plane, however, is that it needs a landing strip. The last option is the zeppelin, which is a very safe way to deliver packages. It doesn’t crash like helicopters and planes do. In addition, it can carry very heavy packages and consumes very little power.
Reliability
The zeppelin might seem as a very nice option, but it is a very slow system. On top of that, it is a very big object, which can be easily hit by other objects. Also landing is complex and the light weight of it is a drawback, because it is very dependent on the weather. The sidewalk cart, on the other hand, is very reliable, because there is little chance that the package will be damaged. However, when the robot gets stuck, it will not be capable of getting free by itself, which will cost a lot of time. The same holds for the walking robot; the package is safe, but if something happens, it will take a lot of time. Speed and accuracy are in favor of a plane or a helicopter, but planes and helicopters are very dependent on the weather. There are solutions for this, but this will impact the flight time and the consumption of the systems.
Safety and privacy
The chance of getting into a collision is not very high for a helicopter or a plane, but when they do, the damage probably is big, and might lead to dangerous situations. However, there are several backup systems possible, so that the helicopter and plane will still be able to fly or land safely in case of one or two malfunctions. For the walking robot, a collision is also very unlikely. The only problem might be people or vehicles bumping into the robot and crossing roads. The same holds for the side walk cart. For both autonomous systems, however, there are programs to safely cross the road. These programs can also be implemented in the road cart. For instance, Tesla and Google car drive autonomously with such a program. The zeppelin, as described before, is a very safe way of travelling. A big drawback is that the vehicle is very big, so it can be hit by objects very quickly. Protection of the system and the package The zeppelin might be a safe way of traveling, but the system can be easily abused. Very little things can cause the zeppelin to crash. This is not the case in the other options. Safety of the package is another important aspect that should be considered. Because of the lifting force, it is easy to lock the package in a safe in the zeppelin. The road cart, the walking robot and the sidewalk cart can also be locked pretty easily. However, the walking robot and the sidewalk cart can be picked up and stolen fairly easily as well. So there should be a solution that prevents that from happening. This is not the case with the plane and the helicopter, but they, just like all options, need some kind of system for authentication. How does the system know who grabs the right package? NFC is probably a good solution for authentication for people using a smartphone or tablet. This is, however, a problem for people not using a smartphone or tablet.
Costs
The costs for all options depend on assumptions, should it be water resistant? How many safety precautions should be added? How many and what kind of sensors should be used? The plane, however, needs extra protective packaging materials, which will increase the costs per delivery. For the walking robot and the sidewalk cart, many disposal stations will be required, which will increase the costs for these options. The costs for the road cart may also be somewhat higher, because of the technology needed to safely deliver packages and to make sure the right package is delivered at the right house.
The choice
We chose the helicopter as the delivery system that is most likely to be implemented in real life. The helicopter is compact, it is capable of landing almost everywhere. Compared to the other options, it is not necessarily more evironmentally friendly. However, it is at least more environmentally friendly than the delivery system right now, with vans and cars. On top of that, it is certainly the most efficient option. The air is rarely used except for airplanes, but those fly much higher than helicopters. Therefore, we think helicopters are an exceptional new way of delivering packages to regular customers. In addition, they are the second most fast option. Only the plane is faster, but there are a lot of drawbacks in using a plane in a delivery system. To finish, it is relatively cheap. The initial costs are quite high, however, further on, there will be almost no additional costs.
The current situation
Rules and Regulation drones (Netherlands)
There are no clear rules for autonomous drones stated in the legislation of the Netherlands, therefore the rules for professional use will be used as rules for the autonomous drones. In the legislation drones are divided in light drones which weight up until max 4 kilogram takeoff weight, and heavy drones which weight up until 250 kilogram takeoff weight. For packaging drones the focus will be on the light drones. The drone always need to give priority to all other air- and land-traffic when they are approaching. They also need to fly in daylight and may not fly in the dark. The drones may not fly higher than 120 meter and need to have a minimum distance from crowds, compact building density, artworks, harbors, industrial areas, railways, public roads, vessels and vehicles of 50 meters. There are also No-Fly-Zones in the Netherlands were no drones are allowed to fly. As you can see are the No-Fly-Zones mainly in big cities and airports. The red area's are the the No-Fly-Zones for the drones.
Rules and Regolation drones (european union)
The rules and regolation about drones in the european union are given by the European Aviation Safety Agency, also called EASA. Although they state clear rules about the use of "Unmanned aircraft" (drones), the paper is still a roadmap or prototype of how it should be in the EU. EASA made a risk based approach to regulation of unmanned aircraft in the so called "JARUS concept of operation" and in this chapter the import conclusions will be stated. The JARUS concept of operation is developed for two main goals. The first goal is integration and acceptance of drones into the existing aviation system in a safe and proportionate manner. And the second goal is fostering an innovative and competitive european drone industry, creating new employement, in particular for Small and Medium sized enterprises (SME's)
Concept of operation
The concept of operation should be regulated in a manner proportionate to the risk of the specific operation. This means that the broad range of operations and types of drones should be taken into consideration and it is proposed to establish three categories of operations and their associated regulatory regime. these three categories are the proposed regulatory framework of the JARUS-paper. The three categories are Open, Specific and Certified. Below the catergories are introduced and shortly explained.
The Open category of drones should not require authorization by an Aviation Authority for the flight but need to stay within the defined limitations for the operation, such as distance from airports and people or privacy.
The Specific catergory of drones will require an authorization by an Aviation Authority for the flight with specific limitation adapted to the operation.
The Certified category of drones will be required for operations with a higher associated risk due to the kind of operation or might be requested on a voluntary basis by organisations providing services such as remote piloting or equipment such as detection and avoid.
Open category
The open category contains of very low risk drone operations, this is why they do not need involvement of the Aviation Authorities, even for commercial operations. Therefore no air-worthiness approval is foreseen and there are also no licenses or approvals needed for the operator and/or pilot. The drones are designed to fulfill simple operations and for small and medium-sized enterprises to gain experience. The risk for other airspace users is very small and moderated through separation with “manned” aviation. The drone may only fly when the following rules are satisfied:
• Under direct visual line of sight (VLOS): 500 m
• At an attitude not exceeding 150 meter above the ground or water
• Not around specified reserved areas (such as airports, environmental and security)
The risk for people on the ground is very low because through the use of low battery/energy aircraft and setting a minimum distance with respect to people. Also flights above crowds are prohibited, but flights above the people which are not related to the operation in cities or populated areas is allowed. And because there is no airworthiness approval required, industry standards could be applied for making these drones.
Specific operation category
The specific operation category should cover the operations that do not meet the specifications of the open category where a certain risk needs to be mitigated by addition operational limitation or higher capability of the involved equipment and persons. For this category the operator should perform a safety risk assessment, identifying mitigation measures, that will be reviewed and approved by the National Aviation Authority. Therefore the operation should be analysed on each specific aviation risk and an authorization is necessary.
Certified category
When the aviation risk rise to a level similar to normal manned aviation, the operation would be positioned in this category. These operations and the aircrafts involved therein would be treated in the classic aviation manner. Multiple certificates would be issued as for manned aviation plus some more specific to unmanned aviation. The difference between specific operations and certified operations is very small but could be based on kinetic energy considerations, type of operations and the complexity of the drones notable in terms of autonomy.
Because the idea is that the drones will be fully autonomous, they will most likely be positioned in the Certified category which means that the drones and their operations would be treated as the classic aviation manner with multiple certificates. What those certificates are is not really clear because this paper is still an prototype and it gives suggestions.
In U.S.A. the FAA already made rules for drones for commercial use. It will be most likely that the rules they have stated are going to be a lot like the rules the European Union is going to make. Therefore the 10 most important rules for commercial use of drones in the U.S.A. and in particular delivery drones, are written down below.
1. Unmanned aircraft must totally weigh less than 25 kilogram, even if it is carrying a package.
2. Daylight-only operations, or civil twilight (30 minutes before official sunrise to 30 minutes after official sunset, local time) with appropriate anti-collision lighting.
3. May use visual observer (VO) but not required.
4. Must yield right of way to other aircraft.
5. First-person view camera cannot satisfy “see-and-avoid” requirement but can be used as long as requirement is satisfied in other ways.
6. Maximum groundspeed of 161 km/h (87 knots).
7. No carriage of hazardous materials.
8. Maximum altitude of 120 meters above ground level (AGL) or, if higher than 120 meters AGL, remain within 120 meters of a structure.
9. External load operations are allowed if the object being carried by the unmanned aircraft is securely attached and does not adversely affect the flight characteristics or controllability of the aircraft.
10. Requires preflight inspection by the remote pilot in command.
These rules are directly copied from the FFA, Source: https://www.faa.gov/uas/media/Part_107_Summary.pdf
Main sources: http://spectrum.ieee.org/automaton/robotics/drones/faa-announces-commercial-drone-rules http://spectrum.ieee.org/aerospace/aviation/a-parallel-air-traffic-control-system-will-let-delivery-drones-fly-safely https://www.faa.gov/news/press_releases/news_story.cfm?newsId=20515
source: https://www.dronewatch.nl/wp-content/uploads/2016/06/EASA_EU-Roadmap-Operation-Centric-Approach-Drone-Ops-v13_160620.pdf source: http://www.agoria.be/nl/Europa-eensgezind-over-regels-voor-Drones source: https://www.easa.europa.eu/easa-and-you/civil-drones-rpas source: https://www.easa.europa.eu/system/files/dfu/UAS%20Prototype%20Regulation%20final.pdf https://www.easa.europa.eu/system/files/dfu/204696_EASA_concept_drone_brochure_web.pdf
The package delivery
The package delivery system can be separated in several steps. One of the biggest delivery companies in the Netherlands is PostNL. A description of a possible package order process looks like this.
1. When a client orders a product from a web shop the web shop sends the product, from its own stockroom, in a package to a sorting center of a delivery company.
2. In the sorting center all the packages that need to be delivered in a certain region in the country are gathered.
3. When there are enough packages to fill a vehicle (van or truck) the packages are transported to the right region and delivered to a pickup point.
4. The clients can check if there package has arrived at their pickup point and can pick their delivery up when they have the time for it.
For an autonomous delivery system the last step in this process is the most interesting. If there is an autonomous system that delivers the packages from a pickup point to the clients home it would save them time. This is especially true for areas where the density of pickup points is not so dense and clients would still have to travel some time to receive their orders.
The different price classes
The way the shipping cost of a package is determined depends on the weight of the package. Usually there is also a maximum size of length and width that the package needs to have. Lastly the shipping cost can be increased if it is requested that the package gets send with urgency. The price classes, based on weight, of PostNL for example are divided like this: [2 kg], [2-5 kg], [5-10 kg], [10-20 kg], [20-30 kg].[2]
The Main Stakeholder: PostNL
The main stakeholder of autonomous delivery systems is PostNL. PostNL a large post office in the Netherlands. In the Netherlands there are several other post offices that are in direct competition with PostNL. In order to move on with this competition it is necessary to deliver the packages and letters as efficiently and fast as possible, in order to meet the demands of the customers in the best way. Because the package delivery is growing in a fast pace thanks to the online shopping behavior of Dutch consumers [5]. PostNL has the biggest market share (50-60%) in the package delivery sector in the Netherlands [5]. For these reasons this sector is the most interesting for PostNL to invest in an innovation such as an autonomous delivery system.
USE aspects In the proces of an autonomous delivery system there are also several other actors that are involved. Here all the actors are described and there role in the final step of the process, the landing, as well.
User:
- The main users are the customers of the delivery company. They use the service of the autonomous delivery system to get what they want, their ordered product. These users are mainly individuals that can be anywhere, so not necessarily at home. The users may be concerned about if the drone can land close enough to them, if not someone else can intercept their order of what happens when they end up being unable to receive their package while the drone already has arrived.
Society:
- The people in traffic are an important part in the society that can get affected by drones. Drones fly through the air so during their traveling they may only get in tough whit planes, but their landing places should not be close to where people may walk around.
- Neighbors of the customers may be affected by drones that fly and land close to their houses.
- The authorities may be anxious about the kind of products the drones are delivering. Are they able to intercept drones to check if they are transporting illegal content such as drugs of illegal fireworks.
Enterprise:
- The main enterprise is the delivery company. In this research the focus lies on PostNL. They use the drones to fur fill their customer’s needs. They might be concerned about safe landing places for their drones. The done has to be unharmed by for example the environment. Also they need a large amount of options for drone landing places in order to make it attractive for their customers to use their services.
- Specific web shops might be interested to have products delivered at a lot of locations. For example shops who sell comping gear that might be broken during a customer’s trip, of perhaps food or medicine. Delivering products on every location might make some products more attractive to buy
PostNL current situation
In the current situation PostNL does not use any autonomous vehicles for the transportation of the packages. The package delivery process has these following steps:
1. The client makes an order on a web shop
2. The package gets send from the web shops stockroom to a sorting centrum
3. The package is processed in the sorting centrum
4. The package is send to a pickup point close to the clients home
5. The client picks the package up from the pickup point
PostNL has 6 sorting centers in the Netherlands [6]. From these centers the packages are transported to the pickup points with large trucks. If the customer demands that the package is delivered to their house directly, the package is transported with a smaller van directly from the sorting center. Because of the low number of sorting center these vans usually have to traverse long distances and transport a lot less packages. In this process PostNL delivers 500.000 packages a day, during heyday this can increase to 1 million [7]. The pickup points in step 4 and 5 of the process are spread across the country, but in the more populated areas there are a lot more pickup points than in the smaller villages. In 2015 there were around 6,8 million people in the Netherlands that live in the big densely populated cities and around 6,5 million people on the rural eras. The rest of the population lived in a transition area between urban and rural [8]. The people that live in the urban areas do not have to look far for a pickup point and because the pickup points can provide for many customers in the neighborhood this is perhaps the most efficient way. But especially for the rural population the pickup points have to sustain customers spread over a large surface. Because there are still a significant amount of people living in these areas it is worth to improve the services in these areas.
Right now if customers choose to have their package delivered to their front door, the vans of the delivery company have to send a van with a very limited package capacity to an area where several customers expect an order. The van has to take the most optimal route to deliver the packages. The points in this process that an autonomous delivery system can improve are:
- costs of delivery employer
- costs of fuel for the van
- speed of delivery
- efficiency of delivery
Packages per day
It is important to know how many packages PostNL delivers a day to discuss if the use of drones will be realistic or not. The next table is formed out of the data given by PostNL itself.
As can be concluded out of this table, the mail in the Netherlands is getting less over the years but the parcels are getting more. If we take 2012 as reference year and thus take it as 100 %, the following table is calculated with using the following formula: Percentage in comparison with year 2012 = ((Nieuw-Oud))/Oud*100%
And to make it more clear that the delivery of parcels is getting higher and higher while the Mail in the Netherlands is getting lower, the next table is formed in which the percentages are calculated against the previous years.
As can been seen in the table the delivery of mail in the Netherlands is drastically going down while the delivery of parcels is going up with almost 50 percent in 2016 in comparison of 2012. Because the amount of parcels a day is necessary for determining, the average parcels per day in 2016 is calculated out of the data received out of tables. There are about 365.242 days in a year and because PostNL does not deliver on Sundays there will be 365.242 – (365.242/7) = 313 days left.
This means that there are averaged 177x10^6/313 = 565379 parcels a day delivered. This number should be a bit lower because of low delivery weeks and holiday weeks such as Christmas or Sinterklaas where a lot of parcels are ordered. Also business packages are included in this number and it goes up to every weight. Because we only want to look to private orders and parcels with a maximum weight of 2 kilogram this needs to be calculated for this average value.
However PostNL does not want to give us any information about how the delivery of packages and their weight is divided and also if it is for business or private. And looking to other companies will not give the right values at all.
Drop off at location
By choosing the helicopter option instead of for example the road cart another issue was introduced: finding a landing place. Because where road carts can only stop in front of a house and drop a package there the helicopter can land practically everywhere. So we will have to think about ways of finding this location to land (if landing is even necessary) to drop of the package. Below a few options are listed:
GPS
The most well-known location finding technologies nowadays has to be the Globally Positioning System or GPS for short. To guide the helicopter from the distribution center to near the package delivery destination GPS will be used. But when it comes to landing there could be other options as well. If we look at using GPS to find the landing position there is namely a bump in the road. GPS is only accurate to around 5m when under open sky, and performs worse when there is something over it like for example a bridge. This inaccuracy is not a big problem when the drop-off location is in the middle of a big meadow, but when delivering in the middle of cities 5m of inaccuracy could mean landing on the street. It speaks for itself that this is not safe for the helicopter itself and the person retrieving the package. This kind of problem could be solved by using some sort of fixed landing spot.
Landing pad
The first sort of such fixed landing spot is something Amazon will use when Amazon Prime Air becomes reality. They want every customer to have a portable landing pad at home on which the Amazon logo is printed. The Prime Air drones will scan the area for this pad when they are at the approximate location and then land on top of it. This solves the problem of the inaccuracy of the GPS as the helicopter will have a fixed landing spot to focus on. A problem with this system is that the pad has to be visible from up in the air. Another problem is that when your neighbor has also ordered something the helicopters do not know which one has to land on which pad.This last problem could be fixed by embedding some sort of unique code in each landing pad which the helicopters can recognize.
Beacon light
A variation of the landing pad to fix the neighbor problem could be a beacon light. This beacon will flash with a fixed frequency which the helicopter will recognize. The helicopter can then land on top of this small beacon in the same way as it would land on the landing pad. The problem which such a beacon is again that is might not be visible from the air. On top of that there could be the problem that due to daylight the helicopter will not see the beacon flash.
Drawn landing space
Another option would be to make it possible for people to draw their own landing area on for example the street with chalk or removable paint. This could be done by for instance drawing a large dot surrounded by two concentric circles. The helicopter then has to search for this drawing using its cameras and approach it in the same way as the landing pad or light beacon. The problem with this idea is that none of the drawn landing spaces will look exactly the same, so the helicopter will have to have very advanced pattern recognition abilities and a universal landing place drawing has to be agreed upon. On top of that rain could wipe out the drawing leaving the drone without a landing spot.
Waiting person
Instead of using something to land on the helicopter could also just look for a person that is waiting for a package and land near him or her. The problem with this is that there is no way how the helicopter can recognize who is standing in the street waiting for their package and who is waiting for something else, especially in busy streets. On top of that there are problems with how close a drone can come to a human before it gets uncomfortable (see also the wiki PRE2015 3 Groep 2). This causes the need for a lot of free space around the waiting person, which might not be present in the busy streets of a city.
Hovering
Apart from landing at the right location using one of the methods above or a combination of them it is also possible to hover at a specific height. The person retrieving the package could then detach the package from the helicopter without it having to land. This would come in handy in areas where landing might be hard such as the very south of The Netherlands where there are hills so the roads are not 100 percent horizontal. Another place where this could come in handy is with multiple story buildings, where the package could be delivered at the right floor level instead of having to go all the way down to the main entrance. Unfortunately we will have the same problem as mentioned in the previous paragraph, namely that people tend to get uncomfortable when a drone approaches them too closely. If the helicopter cannot get within an arm’s length distance from the retrieving person without him or her getting uncomfortable the option of hovering would not work.
Conclusion
From the above it is clear that for the helicopter to determine where to land it has to at least use GPS. However, as this is not accurate enough to deliver the package at the exact wanted location another option for recognizing the landing location has to be added. A few of the above options, namely 'waiting person' and 'hovering', are not viable because as said before people do not like drones to come near. This leaves three options which narrow down to the same idea: a visible marking at the location of delivery. The 'drawn landing space' has the problem that most people will not be able to draw the image accurately enough for the drone to easily recognize it. On top of that the drawing could be wiped out by rainy weather conditions. Therefore this option is also closed out, which only leaves the landing pad and the beacon light. From these two the landing pad is the best option as it does not have problems when sunlight reflects from things which could be mistaken for the beacon light. The chosen option is therefore the landing pad on which an unique (QR-)code will be printed so the drone can distinguish between your landing pad and your neighbors' pads.
Technical Advice
This paragraph will explain some technical aspects about landing a helicopter and taking off again. It is a design proposal which contains information about how a helicopter delivery drone can be built, without specifying certain parts as it depends on different factors. During a landing session or a flight session, it is important that the drone is stable at all times. Also, for a delivery drone a switchable battery is desired, as this removes downtime of the drone caused by charging its battery. Also, the drone needs to be equipped with several sensors in order to be able to fly autonomously.
Control
Autonomous drones should always stay connected with the distribution center as it needs to give signals whether the delivery is going well or whether a task can not be completed. However, wireless connections sometimes experience bad stability, which causes connection losses. During those losses the drone must be able to get into a safe modus, a modus where it stops moving and keeps stabilizing itself. It should also be able to fly back to the distribution center if a new connection can not be established. Also, the drone may experience problems while trying to perform tasks autonomously. For that reason, it should always be possible for a human controller to connect with the drone. This requires multiple control systems and the design of these systems can be done in multiple ways.
First of all the drone should be able to stabilize itself and fly back to the distribution center when a connection is broken. The hardware for this control system should be implemented in the flight controller, which is located on the drone. The system should be intelligent enough to fly to a certain GPS location.
Secondly, it should maintain connection with the distribution center to send feedback on how it is performing its tasks. Also, software should be implemented to allow video streaming and full control of the vehicle by a human controller located in the distribution center.
Center of gravity
For optimal stability the center of gravity has to be as low as possible. A center of gravity which is lower than the propellers causes gravitational forces to automatically compensate for small disturbances. The center of gravity should never be above the propellers as this increases the disturbance which means the system will be naturally unstable. Unstable systems require more power because they need active stabilization.
Also the weight distribution is an important parameter, a wide distribution of weights increases the angular momentum. Increasing the angular momentum will make the helicopter less agile and will also make the helicopter less vulnerable to disturbances. However, greater angular momentum will increase power consumption while turning, as more energy is required to change its rotation.
Sensors
Autonomous helicopters require multiple sensors in order to percept their environment as they cannot receive all the required information from the main server. The required sensors for such a drone have been listed below.
Flight sensor requirements
One of the most import sensors for a helicopter is a gyroscope. Gyroscopes provide information about angular velocity of the drone, which is required to compensate for disturbances on the drone which allows a stable flight. Also accelerometers can be added which allows measuring the linear velocity in different directions. This can be used to calculate flight speed, or compensate for unwanted disturbances. Also a barometer should be required, as this allows the drone to measure its altitude. A small on board computer with a stable radio or internet connection is also required. A 4G connection is easier to implement as the infrastructure has already been built by Dutch telecom companies. However, as connection protocols for radio connections are usually faster, a radio connection could also be used. Both ways can be used cover the entire country. One disadvantage of a radio connection is that the bandwidth is usually low. This does generally not support video streaming which is a requirement.
Autonomous system sensor requirements
In order to navigate autonomously, a global positioning sensor will be required. This way the drone can locate itself and it can follow a flight path when combined with gyroscopes and accelerometers.
Autonomous landing sensor requirements
For autonomous landing several sensors will be required. One important sensor will be a camera because the drone will need to be able to detect its environment to make sure that it does not land on an undesired location. Also proximity sensors can be used to detect whether it is close to colliding with an object or with the ground. Additional sensors may be required depending on the used method for landing and the design of the drone. An infrared camera can also be very useful as this allows the robot to detect persons or animals easily. In this situation the drone can react by hovering above the landing spot, while waiting till the person or animal moved away to a safe distance. In a situation where the landing spot remains obstructed the drone will be forced to fly back to its distribution center.
Battery
In order to pick the right battery size, the distance to the customer has to be determined. As the spread of distribution centers and the maximum flight range of the drone is not the focus on this project, this will be left blank. However, a suggestion can be made on the way of how to decrease downtimes. Be using a switchable battery system the drone does not have to stay at the distribution center to recharge but instead it can swap batteries and deliver the next package. Also, lithium-ion batteries are advised, as they can provide the highest power amongst batteries and they also have the best energy density. Picking the distribution center spread and therefore the desired battery capacity needs some further research.
Package safe
As described by PRE group 1, a package safe will be required to prevent theft of the package. NFC will be used to open the safe on the drone, which only allows authorized persons to open the safe. This makes stealing a package much harder.
Package location
One of the heaviest components in a drone is its battery. For this project packages of two kilograms will also be carried by the drone, making the battery and the package the most heavy components. After landing, the customer will need to be able to pick up the package in an easy way. Assuming the drone will land and turn off its propellers, it will be logical to place the package on the top of the drone. This makes it easily accessible. However, placing it on top of the drone raises the center of gravity, which might give stability issues. This can be solved by placing the battery at the very bottom of the drone, or by raising the position of the propellers.
Immersive problem
Specified aspect
After describing the focus that this investigation will be on, an aspect of the total problem is chosen to describe. This regards the specification of the landing cycle of the delivery drone. This aspect brings up safety of the user, reliability of the drone, technological problems regarding the localization and many more. Therefor a fresh look is needed to overcome these problems. In this chapter first the problems are described and categorized. This brings up the discussion on the importance and possible solutions regarding the problems. Finally all solutions are brought together to generate an complete idea of the delivery cycle and a conclusion is given to this subject.
General Problems
The landing cycle includes many problems. Let’s start to make an sunny day case on the landing cycle. Ideally the drone flies to the location, corrects and assures its position and starts to descend. When it has come out of the ‘airspace’ and it floats on ground level, it specifies its destination. In this time the drone should have informed the user that it has arrived on its destination. After doing so the drone lands and waits for the user to grab the package and, when necessary, signs of for the package. The sunny day case is described in a flowchart.
Fail plans To specify the problems that arise while programming the drone can be described by questioning every move the drone makes. The assurance of its position for instance could go wrong when connection fails. When this happens there are a few things that it could do. The drone could give an error and return to the postal service or postal truck.
However the drone could have problems connecting to the user. When this problem arises the drone picks a safe location close to the address it has to be. Then it floats above street level so no one has annoyed by the zooming object. Then the drone sends a message to the user, thereby telling its location. When the person does not respond the drone flies away and goes back to the postal service. However when the drone connects to the user it waits and responds when the customer has arrived. This gives a specific situation where the error occurs that the drone can’t find the user. This gives therefor a difference between going to the user, such as in the sunny day case, or the user coming to the drone when it fails to connect.
The last problem regarding the sunny day case is how to verify the user. This could be done using the QR code on the landing pad. Also the user will have to be verified, therefor the user could have another QR code for the specific package. This gives an advantage to the current system, where the customer does not have to give a specific identification.
QR-code distance experiment
Introduction
This measurement will determine the maximum distance to reliably scan a QR-code. This includes testing different sized QR-codes, different cameras and different apps to scan a code. It is also important whether the QR-code can be detected while presented under an angle.
Goal
The goal of this experiment is to research what distance between a drone and a carpet is, for scanning a QR-code on the carpet with a camera on the drone. Both vertical and diagonal distances are meaning full to test out.
Background information
Adding a QR-code to the landing carpet creates a point of recognition for the drone. This makes detecting the landing location easy and personal landing carpets can be used as well. This way the drone will not land on the wrong carpet while delivering a package.
QR-codes consists of black and white pixels, the amount of pixels and therefore the amount of data is usually expressed in modules. The amount of modules can vary depending on how many information should be stored in the code. QR-codes use ASCII, this means that every stored character in the code can take on 256 different states. Right now there are 16,8 million inhabitants in the Netherlands. In the table below is listed how many different personal codes can be made with a number of characters.
As can be seen in the table above, three characters will provide enough personal numbers for every household in the Netherlands. However it is smart to pick four numbers as a system with three characters may not be sufficiënt in the future.
The most common used QR-codes use 25 or more modules, as this allows storage of URLS and other more useful information. A 25 module QR-code can store up to 26 characters of data. This is more than sufficient data for the personal code. QR-codes with less modules have relatively bigger black and white squares and are better readable for a camera. Therefore the lowest amount of modulus possible should be used.
One problem with this is that the smallest QR-code generator which is available on the internet generates a QR-code with 21 modulus. This allows to store 9 characters of data, which is more than sufficient.
A test has been performed in 2011 on the minimum size of a QR-code. This experiment tested the maximum distance of reading a QR-code of a certain size. The conclusion of the experiment was that a QR-code with less modules is indeed better readable at longer distances and also a bigger image of the QR-code also improved the maximum range almost linear. During the test a 3-4 megapixel camera was used to detect a 25 module QR-code. It could scan a 46 milimeter wide QR-code at a distance of 45 centimeters, a 30 milimeter wide QR-code at 30 centimeters and a 15 milimeter wide QR-code at 15 centimeters.
When scaling these values, a 1 meter carpet would allow a scan distance of 10 meters. This can however be improved by better software, a better camera and a QR-code with less modules.[11]
Requirements
In order to find the maximum scanning distance, several devices will be needed. In the experiment multiple smartphone cameras will be used to test this maximum distance. Some of the important required devices are listed below.
Method
Measurement environnement: On the wall there is a place to hang a QR code. The area in front of the QR code is divided in four columns, two middle type columns and two side type columns. The columns are divided in position that go further away from the QR code position, the positions are in steps of 5 meters.
1. The first phone is placed in a column on the position closest to the QR code
2. The phone scans the code using all the scanning apps
3. The phone is placed on the next closest step in the column and step 2 is repeated
4. If a app is not able to decipher the code the previous location is noted down and the app is not activated at the next location
5. Until all the apps are unable to decipher the QR code step 3 is repeated
6. When all the apps on the phone have a location noted down all the previous steps will be repeated another type of column
7. When all the phones are finished with all the previous steps the process can start over with another QR code
References
[1] The self driving delivery robot, visited on the 8th of March 2017, visited from: https://www.washingtonpost.com/news/innovations/wp/2015/11/02/this-self-driving-delivery-robot-is-coming-soon-to-sidewalks/?utm_term=.3677b2f3536e ;
[2]The current prices for postal delivery, visited on 8th of March 2017, visited from: https://www.postnl.nl/tarieven/tarieven-pakketten/ ;
[3]The airship 600, visited on 16th of March 2017, visited from: https://en.wikipedia.org/wiki/Airship_Industries_Skyship_600 ;
[4]Costs of the Airship 600, visited on 16th of March 2017, visited from: http://www.newsday.co.tt/news/0,153096.html ;
[5] Autoriteit Consument & Markt, Pauline Gras, 20-05-2016, Nieuwsbericht: Online shoppen zorgt voor explosieve groei pakketvervoer Link: https://www.acm.nl/nl/publicaties/publicatie/15814/Online-shoppen-zorgt-voor-explosieve-groei-pakketvervoer/
[8] Volkskrant, niemand, 18 april 2016, nieuwsbericht: Meer mensen in stad dan op platteland http://www.volkskrant.nl/binnenland/meer-mensen-in-stad-dan-op-platteland~a767483/
… https://www.landenweb.nl/nederland/bevolking/
[9] Link: https://cdn.techinasia.com/wp-content/uploads/2016/10/BN-LM642_amzndr_G_20151130162550.jpg
[11] ... http://blog.qrstuff.com/2011/11/23/qr-code-minimum-size