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Mobile Robots and Service Robots




Industrial robots work in an extremely restricted environment, so their world representation can be quite simple. However, robots that can move about in the environment have also been developed. Military programs have developed automatic guided vehicles (AGVs) with wheels or tracks, capable of navigating a battlefield and scouting or attacking the enemy. Space-going robots including the Sojourner Mars rover also have considerable onboard “intelligence,” although their overall tasks are programmed by remote commands.

Indeed, the extent to which mobile robots are truly autonomous varies considerably. At one end is the “robot” that is steered and otherwise controlled by its human operator, such as law enforcement robots that can be sent into dangerous hostage situations.

Moving toward greater autonomy, we have the “service robots” that have begun to show up in some institutions such as hospitals and laboratories. These mobile robots are often used to deliver supplies. For example, the Help-Mate robot can travel around a hospital by itself, navigating using an internal map. It can even take an elevator to go to another floor.

Service robots have had only modest market penetration, however. They are relatively expensive and limited in function, and if relatively low-wage more versatile human labor is available, it is generally preferred. For now mobile robots and service robots are most likely to turn up in specialized applications in environments too dangerous for human workers, such as in the military, law enforcement, handling of hazardous materials, and so on.

Smart Robots

Robotics has always had great fascination for artificial intelligence researchers. After all, the ability to function convincingly in a real-world environment would go a long way toward demonstrating the viability of true artificial intelligence. Building a smart, more humanlike robot involves several interrelated challenges, all quite difficult. These include developing a system for seeing and interpreting the environment (computer vision) as well a way to represent the environment internally so as to be able to navigate around obstacles and perform tasks.

One of the earliest AI robots was “Shakey,” built at the Stanford Research Institute (SRI) in 1969. Shakey could navigate only in a rather simplified environment. However, the “Stanford Cart,” built by Hans Moravec in the late 1970s could navigate around the nearby campus without getting into too much trouble.

An innovative line of research began in the 1990s at MIT. Instead of a “top down” approach of programming robots with explicit logical rules, so-called behavior-based robotics works from the bottom up, coupling systems of sensors and actuators that each have their own simple rules, from which can emerge surprisingly complex behavior. The MIT “sociable robots” Cog and Kismet were able to explore the world and learn to interact with people in somewhat the way a human toddler might.

Swarm robotics is an approach to robotics that emphasizes many simple robots instead of a single complex robot. A robot swarm has much in common with an ant colony or swarm of bees. No individual in the group is very intelligent or complex, but combined, they can perform difficult tasks. Swarm robotics has been an experimental field, but many practical applications have been proposed.

A traditional robot often needs complex components and significant computer processing power to accomplish its assigned tasks. In swarm robotics, each robot is relatively simple and inexpensive. As a group, these simple machines cooperate to perform advanced tasks that otherwise would require a more powerful, more expensive robot.

Using many simple robots has other advantages as well. Robot swarms have high fault tolerance, meaning that they still will perform well if some of the individual units malfunction or are destroyed. Swarms also are scalable, so the size of the swarm can be increased or decreased as needed.

One use that researchers have demonstrated for swarm robotics is mapping. A single robot would constantly need to keep track of its location, remember where it had been and figure out how to avoid obstacles while still exploring the entire area. A swarm of robots could be programmed simply to avoid obstacles while keeping in contact with other members of the swarm. The data from all of the robots in the swarm is then combined into a single map.

Swarm robotics has been an emerging field, and it has presented unique challenges to researchers. Programming a swarm of robots is unlike other types of programming. The model of distributed computing — using many computers to work on a single large task — is somewhat similar. Unlike distributed computing, however, each individual in swarm-style robotics deals with unique stimuli. Each robot, for example, is in a different location at any given time.

Some approaches to swarm robotics use a control unit that coordinates other robots. Other approaches use techniques borrowed from nature to give the swarm itself a type of collective intelligence. Much of the current research in the field focuses on finding the most efficient way to use a swarm.

Swarm robotics is a concept that's buzzed around since the 1980s, but now the technology is starting to fly. The environmental applications being explored range from coral restoration and oil spill clean-ups to precision farming – even the creation of artificial bees to pollinate crops.

Dr Roderich Gross, senior lecturer in robotics and computational intelligence, explains the concept: "In a swarm system there is no single point of failure – if a unit fails, the whole system keeps on going. Wherever you have a very heavy load that a human cannot manipulate, using a swarm of robots to do the job would be very sensible. That could be in a factory, transporting boxes. Or it could be a search-and-rescue scenario – maybe a collapsed building and you need to remove a very heavy part, or working in contaminated environments."

Scientists and designers at Heriot-Watt University have been looking at using a swarm of "coral bots" to restore ocean habitats. Dr Lea-Anne Henry of the university's school of life sciences believes that swarm robotics can "revolutionise conservation". Agriculture is looking into the potential for using swarms too. Professor Simon Blackmore, head of engineering at Harper Adams University works on larger robots that can work in fleets, able to identify weeds and administer microdots of chemicals with the result of using 99.9% less herbicide than traditional methods. He believes that, though the technology may appear an expensive luxury, it may have a wider appeal than the latest generation of conventional farm machinery such as expensive tractors and harvesters.

Perhaps the most famous – and controversial – swarm project to date is Harvard University's "Robobees", aiming to find an artificial solution to pollination to address the current decline in the global bee population. Here the robotic swarm is attempting to replicate one of nature's greatest swarms. But even setting aside the ethics of attempting to replace nature's pollinators, the idea may remain impossible.

The problems of organizing a swarm haven’t kept people from imagining what swarm robotics could offer some day. Some scientists envision a swarm of very small microbots being used to explore other planets. Other proposed uses include search-and-rescue missions, mining and even firefighting. When used with nanobots — microscopic-size robots — swarm robotics could even be used in human medicine.

Future Applications

A true humanoid robot with the kind of capabilities written about by Isaac Asimov and other science fiction writers is not in sight yet. However, there are many interesting applications of robots that are being explored today. These include the use of remote robots for such tasks as performing surgery (telepresence) and the application of robotics principles to the design of better prosthetic arms and legs for humans (bionics). Farther afield is the possibility of creating artificial robotic “life” that can self-reproduce.

Notes:

The Turk, also known as the Mechanical Turk or Automaton Chess Player was a fake chess-playing machine constructed in the late 18th century. From 1770 until its destruction by fire in 1854, it was exhibited by various owners as an automaton, though it was exposed in the early 1820s as an elaborate hoax.

Karel Čapek (1890 – 1938) was a Czech writer of the early 20th century best known for his science fiction, including his novel War with the Newts and the play R.U.R. that introduced the word robot.

Sojourner was the Mars Pathfinder robotic Mars rover that landed on July 4, 1997 and explored Mars for around three months.

Shakey the robot was the first general-purpose mobile robot to be able to reason about its own actions. While other robots would have to be instructed on each individual step of completing a larger task, Shakey could analyze the command and break it down into basic chunks by itself. It was developed from approximately 1966 through 1972 at the Artificial Intelligence Center of Stanford Research Institute

MIT (Massachusetts Institute of Technology) is a private research university in Cambridge, Massachusetts, founded in 1861 in response to the increasing industrialization of the United States. The institute adopted apolytechnic university model and stressed laboratory instruction.

RoboBee is a tiny robot capable of tethered flight, developed by a research robotics team at Harvard University. The 3-centimeter (1.2 in) wingspan of RoboBee makes it the smallest man-made device modeled on an insect to achieve flight.

 

 

Assignments

 

1. Translate the sentences from the texts into Russian in writing paying attention to the underlined words and phrases:

 

1. True robotics began in the mid-20th century and has continued to move between two poles: the pedestrian but useful industrial robots and the intriguing but tentative creations of the artificial intelligence laboratories.

2. The early industrial robots had very little ability to respond to variations in the environment, such as the “work piece” that the robot was supposed to grasp being slightly out of position.

3. At one end is the “robot” that is steered and otherwise controlled by its human operator, such as law enforcement robots that can be sent into dangerous hostage situations.

4. Service robots have had only modest market penetration, however.

5. After all, the ability to function convincingly in a real-world environment would go a long way toward demonstrating the viability of true artificial intelligence.

6. Swarm robotics has been an emerging field, and it has presented unique challenges to researchers.

7. Other approaches use techniques borrowed from nature to give the swarm itself a type of collective intelligence.

8. Swarm robotics is a concept that's buzzed around since the 1980s, but now the technology is starting to fly.

9. He believes that, though the technology may appear an expensive luxury, it may have a wider appeal than the latest generation of conventional farm machinery such as expensive tractors and harvesters.

10. Perhaps the most famous – and controversial – swarm project to date is Harvard University's "Robobees", aiming to find an artificial solution to pollination to address the current decline in the global bee population.

 

 

2. Answer the following questions:

 

1. How was the term “robot” coined?

2. What are the limitations of industrial robots?

3. Where are mobile robots being used?

4. What approaches does the development of smart robots call for?

5. What are the advantages of swarm robotics over conventional approaches?

6. What are the major challenges posed by swarm robotics?

7. Where can swarm intelligence be of practical assistance?

 

 

3. Translate into English:

 

Проект TERMES, реализуемый в течение четырех лет исследовательской группой самоорганизующихся систем Гарвардского университета, в основе которого лежит моде­лирование поведения колонии термитов, имеет конечную цель в создании масштабируемой системы искусственного интеллекта, в основе которой лежат простейшие роботы, способные уже сейчас совместными усилиями строить башни, пирамиды и другие сооружения, возводя даже до­полнительные элементы, позволяющие роботам подни­маться выше.

Данный проект имеет абсолютно другой подход к ор­ганизации работ, нежели традиционная иерархическая система, в которой основной план движется, дробясь на множество мелких задач, от руководителей высшего звена через череду менеджеров и специалистов к непосредствен­ным исполнителям. Вместо этого, модель колонии терми­тов предусматривает выполнение работ каждым роботом обособленно, без всякого централизованного руководства. Исследователи объясняют, что роботы действуют при по­мощи принципа стигмергии (stigmergy), принципа неяв­ных коммуникаций, когда каждый индивидуум распознает изменения окружающей его среды и корректирует свои собственные планы в соответствии с этими изменениями.

Благодаря использованию принципа стигмергии, ро­боты TERMES могут работать группами от нескольких эк­земпляров до нескольких тысяч, выполняя единую задачу, но абсолютно не общаясь друг с другом. Отсутствие цен­трализованного управления означает, что у системы в це­лом имеется крайне высокий уровень надежности, выход из строя одного экземпляра робота не приводит к неработо­способности системы, а оставшиеся работы продолжают работу, не замечая этого факта. Такой подход позволяет сделать роботов максимально простыми, ведь им не требу­ется наличия радио- или другого коммуникационного ка­нала, работающего на иных принципах. Роботы TERMES, созданные гарвардскими исследователями, имеют всего по четыре датчика, по три независимых привода и несложный механизм, позволяющий брать, переносить и укладывать строительные блоки.

 





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