ABSTRACT
People tend to have very different perceptions of what a robot is. For some people, a robot is an intelligent and sophisticated machine. A robot must have the capability to move autonomously and make decisions on how to accomplish its task without any human intervention. From this perspective, examples would include mobile robots used in space exploration, or looking a bit into the future, autonomous intelligent cars.Other people think of robotsmore in the context of industrial automation. In this context, a robot is typically a robotic arm used in assembly lines, for example, in car manufacturing. Those robots tend to perform the same repetitive motions in their highly controlled and predictable environment. Precision and accuracy are paramount for this kind of robots. Finally, it is not uncommon to treat a part or even a molecule as a robot. A major issue in production lines is how to process parts that arrive at random orientations and have to be oriented in a certain way before they are used for assembly. During the last few years, it has become a very important area of research to identify howbigmolecules-such as proteins-move, by adapting ideas that were initially developed for robots. This chapter covers some of the fundamental principles and presents several examples of algorithms that are currently used in robotics. Robot algorithms differ in significant ways from traditional computer algorithms. The latter have
full control over, and perfect access to the data they use, letting aside, for example, problems related to floating-point arithmetic. In contrast, robot algorithms eventually apply to physical objects in the real world, which they attempt to control despite the fact that these objects are subject to the independently and imperfectly modeled laws of nature. Data acquisition through sensing is also local and noisy. Robot algorithms hence raise controllability (or reachability) and observability (or recognizability) issues that are classical in control theory but not present in computer algorithms.
