An Introduction to Space Robotics

Abstract

As the preface to An Introduction to Space Robotics proclaims, this work is aimed squarely at `students and professionals engaged in the analysis and design of robotic space missions'. As a reviewer I should come clean and state that this does not apply to me - rather, as a space scientist I am very much a user (some would say, abuser) of robotics within the context of space exploration. To me robotics are a means to an end, and often a limitation on my own personal scientific enquiry. And so, having made my position clear, what were my impressions about the book itself? The first thing that hits you when you pick it up is its high mass - this is a heavy book (one that would make your arms ache if not supported on a desk). This characteristic arises because of its overall high quality - the hardback format, the glossy paper and clear print; with 663 pages arranged into 21 chapters you will certainly feel like you have obtained your money's worth if you purchase it yourself. There is no question: the book itself will last a lifetime. As far as content is concerned, the opening three chapters introduce the subject of space robotics with reference to the environmental considerations under which they need to operate, and with examples from past mission successes. The next two deal with the man-machine interface (in these enlightened times we really should try to think about a human-machine interface) and systems design. These two chapters begin to establish the overall direction of the book, which takes, as two pertinent examples of space robotics, in-orbit servicing and planetary rover exploration. These two concepts are described with regard to telerobotic control processes initiated from a ground station, which introduces the notions of robotic programming languages, voice recognition software, virtual reality systems, and the overall ground station computer hardware. Then a hypothetical freeflying space robot dedicated to satellite servicing is introduced; known as ATLAS, this device is used as an example to describe the complex interrelationships which have to be considered within the overall systems design. As a space scientist the underlying concepts are entirely relevant to, say, a robotic device that would reach out from a spacecraft and grab a particular rock from the surface of an asteroid. Interestingly, in this example, the constraints on ATLAS would become even tighter since the operation may need to be done without imparting any contamination to the sample in question (something else for engineers to worry about). Having said that, space scientists would do well to appreciate the technical limitations attached to robotics (which might then prevent them from asking for the impossible). The text then changes gear and goes into a chapter-by-chapter account of some of the specific elements of robotic manipulation, i.e. sensors, control systems, dynamics, kinematics etc. This is all pretty standard robotic stuff, but is dealt with in a marvellous degree of detail. After two further chapters on imaging and autonomous control, there follow six which are very much oriented towards spacecraft themselves - orbit and attitude control, avionics, communications, power supplies, structures etc. At every possible opportunity the text deviates from the flow of generic information to consider a real spacecraft example. This constantly emphasizes the very practical applicability of the book. Finally, there are chapters which consider the commercial and legal ramifications of robotic space missions, and a conclusion section that focuses on the future of space exploration, including the International Space Station, and resource utilization on the Moon and planetary bodies. So, quite apart from being a heavy book, its content is also best described as heavyweight; it is hard to imagine that anything has been missed out. In conclusion this book should be on the shelves of all academic libraries that specialize in engineering, mechatronics or space science. Furthermore, if space robotics is to be your chosen career then clearly you need to have your own copy. As far as this subject goes, Ellery's book should surely be considered as the Bible. I P Wright