PRE2020 4 Group2

USAR robots

Group members

Name	Student ID
Jasmijn de Joode	1358073
Robin Foppen	1394746
Mirre Bosma	1266489
Dirk de Leeuw	1358081
Job van Heumen	1380036

Problem statement

With our climate changing natural disasters are happening at a larger rate. Thus, we, as humanity, need to prepare for these disasters and try to prevent them. Unfortunately, this will not always work and in the cases this doesn’t work these disasters can cause a lot of damage. One of the results of natural disasters is collapsed buildings. When this happens search and rescue is necessary to save the people trapped inside the building.

Experience has shown that the chances of survival are highest when people have been rescued within 72 hours . After this time frame, the number of survivors found drops drastically. So, it is especially important to have all hands on deck as soon as possible. This is where robots can be of great help.

One of the reasons that we do not make this 72 hour deadline, is that it might be too dangerous for the search and rescue workers to go inside of the rubble. There is danger of collapse, which for the workers could be detrimental. Luckily, robotica can help us work around this problem in various ways. Robots can be used to map the building underneath the rubble and help find victims in places the rescue workers are not able to access.

Advances in robotics still have to be made to make this work even better. So we will define the shortcomings that exist today and try to find where the next innovations can be made.

Deliverables

For this project, we want to do a literature study on different Urban Search and Rescue robots. Our objective for this research is to find possible limitations of the current state of the robots, and give suggestions for short and long-term future improvements on both the technology aspect (efficiency) as well as the human-robot interaction aspect. The current state of art of the robots will be investigated, whereupon next the limitations will rise and further developments will be determined.

What to do in case of a structural collapse?

As the title pretty much already tells us, this section is about what to do in the case of a collapsed building. We already saw that in a rescue mission, the first 72 hours are the most important for rescuing survivors. In this section we will see what needs to be done to act as safely and efficiently as possible.

There are multiple sources that give a 5 step plan in case of a collapsed building. Although they differ slightly, they all boil down to the same 5 steps. We will use the steps set by the OCHA

• The first step is initializing the search and rescue teams as quickly as possible.
• The second step is analysis of the building. What are the dangers for rescue workers when entering the building?
• The third step is finding the survivors in the building.
• The fourth step is getting people out of the rubble.
• And the fifth and last step deciding when to close the operation.

Step 1 - initializing search and rescue teams

On the site of USAR, it says that they are available in the Netherlands within 4 hours and internationally they can be on-site within 24 hours. As we saw in the problem statement, it is very important for search and rescue teams to be on-site and working as quickly as possible, since the first 72 hours are the most important in recovering survivors.

Step 2 - analyse the building

The book Protecting Emergency Responders, Volume 4: Personal Protective Equipment Guidelines for Structural Collapse Events gives a great overview of the different dangers there are in a search and rescue mission. So, we will use this book to give a short summary of the different kinds of hazards. They make the differentiation between physical, chemical and biological hazards. These three hazards are in turn divided into sub hazards. So, we will look at these separately, since they all need different approaches to dealing with them.

Physical hazards

Electric shock

After a collapse, electric cables can be downed and severed. Rescue workers and people who were in the building at the moment of the collapse can get hurt from this in several ways. Rescue workers can get hurt from direct contact with an electrical source, but electricity can also reach a rescue worker through the air. Possibly clothing can catch fire because of heat generated by an electric source. And of course, if there is flooding, electricity could also travel through the water. Basically, there are many ways in which severed wires can hurt rescue workers. So, it is very important to make sure that electric lines are not energized.

Fires and explosions

There might be fuel stored on-site or be gas leaks that provide fuel for fires or explosions. an explosion could have been the cause of the collapse in the first place, or maybe pipes have burst because of the collapse. In either case, it is important to check. Especially, since electric cables might be severed, they can easily spark a fire. Also, the collapse might be the result of a terrorist attack. In this case, there might for example still be bombs that could go off.

Hearing loss because of excessive noise

The site of a collapsed structure is very noisy. For example, in order to free people from the rubble, excavating equipment is needed. These tools for drilling and digging make a lot of noise.

Asphyxiation hazard

There are a number of reasons why there might not be enough oxygen in a certain space. There can be oxygen consumption or oxygen displacement. Oxygen consumption can happen when there is a combustion in a poorly ventilated space or if there are a lot of people in a small space. Oxygen displacement can occur when large amounts of gasses are released into a (small) space.

Chemical hazards

There are numerous chemicals that can be released due to the collapse of a building. The chemicals can come out of the building materials that are pulverized or chemical storage tanks or containers can be damaged because of the collapse. If there is incomplete combustion or fires, this can increase the amount of chemicals in the air.

There is a lot to say about the types of chemical hazards and how these chemicals can be released, but for now, it is enough to just state that there are chemical hazards.

Biological hazards

The last hazard to discuss is biological hazards. Possible ways for pathogens to be released are from damaged sewer systems or they can be bloodborne from infected patients.

Just like with the chemical hazard, there is a lot more to say about this, but for now, just the fact that they exist is enough.

Step 3 - find survivors

This step has been most researched in combination with robot assistance. On multiple occasions, robots have helped find people caught in the rubble.

Here we will mainly look at ways where no robots are used.

Rescue dogs

The use of rescue dogs is very important. The exceptional nose of dogs can help the rescue workers locate victims. One of the downsides of using dogs is the communication between the dog and its handler. This lack of communication might lead to incomplete or inaccurate information, which in turn could mean missing someone. . Another problem is that dogs might get to a location where rescue workers are not (yet) able to get. This is why research has already been done as to how robots might assist canine search.

Knowledge of locals

Locals might know where in the building the chances are the biggest that people were there at the time of the collapse.

Weak buidings

Weak buildings can of course collapse very easily, but the material is often also very light. Which means that the chance of people surviving even though they are covered under the building, is higher than when a building is made of very heavy material.

Strong buildings

Certain parts of buildings are stronger than other parts. Under/in parts that are very strong, the chances are largest that there are open spaces where people are caught in. So, if people were inside these spaces at the time of the collapse, the possibility of survival is quite high.

Video cameras

Cameras with heat vision.

Listening

Shifting rubble

When lifting debris, limbs of survivors can become visible.

Step 4 - rescue survivors

Once the hazards of going into the building have been identified and it is known where survivors are located, the next step is to rescue the survivors. The only way to do this is by creating pathways through which the victims can be reached and help them get out.

Step 5 - close the operation

At some point, the chances of finding survivors has become so low, that the operation can be closed. But deciding when this is, is always a difficult decision to make.

Summary

After discussing the different steps, we have decided to zoom in on step 2 - analysis of the building. Step 1, 4 and 5 are difficult to improve with the use of robots. In step 2, robots can be of great value. Since getting to work as quickly as possible is of utmost importance, what better to help us find gas leaks, severed cables or other dangers than robots.

State of the art

In this section we look at examples of the newest/best-developed robots that exist at this time. The different robots have been divided into ground robots and aerial robots. The ground robots are then again split up into legged robots and tracked and wheeled robots. There are also robot competitions. What is the value of this?

We will discuss the state of the art of Search and Rescue (SAR) robots. There are two types of SAR robots, namely Urban Search and Rescue and Maritime Search and Rescue. We will only focus on Urban Search and Rescue (USAR). USAR may be needed for multiple kinds of emergencies, for example earthquakes, storms and tornadoes, floods and technological accidents. Research and projects are concerned with localizing, extracting and medical stabilization of trapped victims.

Since disaster areas are often dangerous for humans, it is convenient to make use of robots to investigate the area and help victims. Robots are also capable to carry out tasks which are very hard or even impossible for human rescue teams, for example finding victims with the help of thermographic cameras.

Current applications of USAR robots do not include autonomous robots. This is because current technology is not advanced enough to develop fully autonomous robots which are capable to cope with these complex, unpredictable and unstructured environments. Maybe in the far future there will be autonomous robots which can execute USAR missions without any help of humans. However, this is not realistic on short term. This does not mean that robots are not helpful in current USAR projects and missions, but we need to find a balance in the human-robot interaction. There are different kinds of USAR robots, we will discuss ground and aerial robots.

Ground robots

One of the primary challenges for ground robots is the movement in the environment. This is a hard task, because in contrast with for example traffic environments, disaster areas are often unstructured, unpredictable and unknown. It usually also contains many obstacles. To avoid these obstacles, USAR teams can make use of legged ground robots.

Legged robots

Legged robots can help a rescue team with carrying heavy payloads, are able to perform long-duration missions, and are able to interact with the environment and to move in complex terrains. They should be able to apply different gaits and maneuvers depending on the terrain and obstacles. .

ANYmal

ANYmal is developed to be deployed on the field and work in harsh conditions. It is designed for autonomous operation in challenging environments. It has incorporated laser sensors and cameras, which enable the robot to perceive its environment, accurately localize, and autonomously plan its navigation path and carefully select footholds while walking. It only weighs about 30 kg, so the robot can be easily transported by a single operator. Researchers are still further improving the locomotion skills of ANYmal to make it capable of dealing with situations that might be encountered in a search and rescue scenario and they will integrate an arm on ANYmal: this will result in the robot having the potential to manipulate objects, to move through closed doors, or simply to use the arm as an additional point of contact. ANYmal has a proven capability of working in harsh environments with the potential for use in a wide-range of applications. It can operate in rough outdoor locations, crawl through pipes, and access buildings over steps and stairs, making it perfect for use on industrial platforms, in mines, construction sites, or patrolling remote locations.

KROCK-2

Krock-2 is another quadruped robot with sensors and subsystems to make it suitable for disaster response missions. The robot's force sensors give the robot the ability to feel its immediate environment, which can be used to improve its locomotion capabilities. It has the ability to surpass obstacles twice as high as the robot itself (15 cm) and move under narrow passages of the same height. The construction of the robot is modular, meaning that pieces can be replaced easily on the field. It also presents mechanical symmetry from top to bottom, front to back and left to right, making the robot able to operate in any condition after a fall.

Atlas

Atlas, unlike the other legged robots mentioned here, is more human than animal like and walks on two legs instead of four. Atlas is intended to aid emergency services in search and rescue operations, performing tasks such as shutting off valves, opening doors and operating powered equipment in environments where humans could not survive. It is specialized for mobile manipulation and is very adept at walking over a wide range of terrain, including snow, and can do back flips and cartwheels. It is electrically powered and hydraulically actuated. It uses sensors in its body and legs to balance, and it uses LIDAR and stereo sensors in its head to avoid obstacles, assess the terrain, help with navigation, and manipulate objects, even when the objects are being moved. In the 2015 DARPA competition of robotics, Atlas was able to complete all eight tasks as follows: Drive a utility vehicle at the site; Travel dismounted across rubble; Remove debris blocking an entryway; Open a door and enter a building; Climb an industrial ladder and traverse an industrial walkway; Use a tool to break through a concrete panel; Locate and close a valve near a leaking pipe; Connect a fire hose to a standpipe and turn on a valve.

BigDog

Another four-legged robot is the BigDog, which is a military robot. So this robot is not created particularly for rescue. It was created in the hope it would be able to serve as a robotic pack mule to accompany soldiers in terrain too rough for conventional vehicles. Instead of wheels or treads, BigDog uses four legs for movement, allowing it to move across surfaces that would defeat wheels. The legs contain a variety of sensors, including joint position and ground contact. BigDog also features a laser gyroscope and a stereo vision system. It has the ability to travel on icy terrain, in mud, walk through a forest and recover balance after skidding in slope or when kicked by someone. The project however was shelved after the BigDog was deemed too loud for combat. By the hand of this robot, Boston Dynamics has developed more quadruped robots like WildCat (which was the fastest untethered quadruped robot in the world in 2013), LittleDog, and Spot.

MIT Cheetah

Another quadruple-legged robot is MIT Cheetah: The total power utilized by the robot is about 973 W, and the cost of transport (COT) is 0.5, which is very much similar to running animals. The robot can run on a treadmill as well as grassy and uneven terrain in a controlled manner. The robot can jump over hurdles up to 400 mm high while running at 2.5 m/s.

Why (four-)legged robots?

Legged robots have more potential than wheeled or and tracked robots because they can work in cluttered terrain, complex and hazardous environments, since they are more like humans and animals. The quadruped robots are the best choice among all legged robots related to mobility and stability of locomotion. The four legs of the robot are easily controlled, designed, and maintained as compared to two or six legs. However, legged robots in general are hard to control. These robots need to have complicated structures with multiple legs and actuators for stability and multiple sensors to perceive their environment. So it is quite a challenge to develop a robot that is able to walk properly in disaster areas. This is one of the reasons that legged robots are currently not used as much as wheeled or tracked robots in real-life situations. Another technical problem is that legged robots in a disaster environment need to be very adaptable, not just in their intended design, but they also need to be able to adapt to possible damage, for example to the loss of one of its legs. This is important, because legged robots are usually more fragile than wheeled or tracked robots. Learning algorithms can be used to solve this problem. Another disadvantage of legged robots is that they are less cost effective than wheeled robots. The physical layout of industrial sites, consisting of stairs, gaps and other obstacles, adds a layer of complexity, preventing the use of traditionally wheeled or tracked robots. While drones can overcome some of these problems, they cannot operate in bad weather and their payload capacity and energy autonomy can be limiting. (https://www.hazardexonthenet.net/article/167536/ANYmal-A-unique-quadruped-robot-for-harsh-environments.aspx) (source: https://www.sciencedirect.com/science/article/pii/S2090447920302501) There are many things to look at when finding a good quadrupled robot: the weight (which depends on the actuation system), if the actuators are hydraulic or electrical, dimensions, size, and the number of active joints present in each leg of the robot. The two-joint structure leg is easy to control and design, commonly used in four-footed robots like spot mini, littledog, ANYmal, etc. However, from a biological point of view, toed animals, such as tigers, leopards, lions, and wolves, have a three-joint structure in their legs, which imparts excellent advantages in running speed and energy efficiency.

Tracked and Wheeled robots

Another type of ground robots are tracked and wheeled robots. One of the advantages of these type of robots over legged robots is their stability and that these robots are easier to navigate. However, these robots are not as good at moving through challenging terrain as legged robots, because tracked and wheeled robots are not able to step over obstacles. Since tracked and wheeled robots do not need to have such complicated structures as legged robots, several recent European projects have already utilized tracked or wheeled ground platforms in different rescue environments. We will discuss two European projects: ICARUS and TRADR.

Aerial Robots

Unmanned Aerial Vehicles (UAV’s) have many benefits over ground vehicles. They can be used to get a good view on the disaster area, but they can also be used to get to small spaces where UGV’s cannot reach. However UAV’s also have some disadvantages. Because of their size and power constraints, UAV’s are not able to carry heavy equipment or medical supplies with them. Furthermore, they are usually quite fragile. This means that UAV’s need to be very careful to not collide into walls or other obstacles.

Contests

ICARUS

ICARUS focuses on developing integrated tools for search and rescue, utilizing teams of air, ground, and marine vehicles. One of the projects of ICARUS is an unmanned ground vehicle (UGV) which consists of two UGV’s: One large UGV and one small UGV. The larger UGV is used as a Mobile sensor platform. The large UGV collects large amounts of data that is necessary to navigate through the environment. Platform for powerful manipulator. The large UGV will be able to remove small obstacles from its path or to free a victim. Transport platform for small UGV. The large UGV will be used as a platform to carry several small UGV’s. The small UGV is used to enter collapsed buildings without damaging these buildings. These small UGV’s can be used to find and help trapped or injured victims. Since this vehicle is small it cannot be equipped with sophisticated sensors nor with a powerful computation unit. For this reason, the level of autonomy of this vehicle will be quite low.

TRADR

After the earthquake in Amatrice, Italy in 2016, a team of the TRADR project made use of two UGV’s and three unmanned aerial vehicles (UAV’s) (see Figure 2) to provide a 3D model of two partially collapsed churches. The mission was a success and the UGV’s and UAV’s were able to collect enough data for a high quality 3D model of the two churches.

Technological development

Natural disaster scenarios are one of the reasons why ground robots are being developed. One of the main challenges is to be able to navigate on complex terrain. Another reason that pushes the technological development of tracked and wheeled robots are open robotic challenges. Some examples are: The ARGOS challenge (ARGOS, 2017). This challenge was won by team argonauts with a tracked robot from the company TAUROB (TAUROB, 2017) (see Figure 3). The DARPA Robotic Challenge. After the nuclear disaster at Fukushima in Japan 2011 it became clear that humans are very vulnerable to natural and man-made disasters. Existing rescue robots were at that time unable to prevent or reduce the damage. This was the reason that the Challenge was created in 2012 by the Defense Advanced Research Projects Agency (DARPA). The primary goal of the challenge was to stimulate the development of human-supervised ground robots which should be able to execute complex tasks in dangerous environments.

(possible) applications of ground robots at disaster zones

some (possible) applications of ground robots are:

Remote sensing (obtaining information from a distance). For example in disaster areas (thermographic) cameras could help a robot to find trapped or injured victims.

Victim interaction (helping victims) or extraction (saving trapped victims). For example supplying food to trapped victims or helping trapped victims to be released.

Remote firefighting. In combination with a remote medic a ground robot can be used to interact with victims through telepresence.

Logbook

Week 1 and 2

Name	Student ID	Time spent	Tasks
Jasmijn de Joode	1358073	4.5h	Write deliverables (0.5h), Do research (4h)
Robin Foppen	id	h	idk
Mirre Bosma	1266489	4h	Write problem statement (1.5h), Do research (2.5h), Write wiki page (0.5h)
Dirk de Leeuw	1358081	4.5h	Problem statement (2h) Research (2.5h)
Job van Heumen	1380036	5h	Do research and write state of the art (4.5h), write wiki page (0.5h)

Week 3

Name	Student ID	Time spent	Tasks
Jasmijn de Joode	1358073	3.5h	Research legged robots (3h), edit wikipage (0.5h)
Robin Foppen	id	h	idk
Mirre Bosma	1266489	5.5h	Research what needs to be done in case of collapse (4.5h) Order wiki page, add short summary begin sections and reference correctly (1h)
Dirk de Leeuw	1358081	3h	Research Wheeled and tracked robots(3h)
Job van Heumen	id	h	idk

References