Parallel robots. (English) Zbl 0983.70002

Solid Mechanics and Its Applications. 74. Dordrecht: Kluwer Academic Publishers. xiv, 355 p. Dfl 300.00; $ 153.00; £93.00 (2000).
The book presents the state-of-the-art of research and application of parallel robots. It is an extended and updated version of the French book “Les robot parallèles” (1997), and is the first English research monograph on this active field of research. The name parallel robots stands for a special kind of multi-loop, parallel acting mechanical devices, which are superior to serial robots, e.g. with respect to accuracy, rigidity and load-to-weight ratio. The introduction contains a characterization of serial robots and other architectures of robots. Then the basics of parallel robots (definitions, degrees of freedom and degrees of parallelism) are given. In chapter two many different designs are listed and evaluated. For most of the actually built designs, the author gives Internet references for further information. Chapter two also introduces the Jacobian of manipulator, which is an operator that transforms the instantaneous twist into joint velocities. Inverse kinematics and methods for calibration are dealt with. A large chapter is devoted to direct kinematics. In the direct kinematics, positions and orientations of the end-effector are asked for when the geometry and joint parameters are given. The author develops in great detail algorithms and mathematical methods for various designs, starting from a planar 3-RPR mechanism to the most general case of spatial six-legged platform. In singular configurations the manipulator looses stiffness and gains an infinitesimal degree of freedom. Line geometric methods and interval analysis are applied to compute singular positions. The author discusses various numerical problems, and mentions pathological designs and singularity free path planning. In a chapter on workspace one can find a thorough analysis of different definitions of workspace and many examples for which a detailed representation of the workspace is given. The last three chapters deal with velocity and acceleration properties of manipulators, and present static and dynamic methods to design a parallel manipulator for a prescribed task (or set of tasks). In the references one can find more than 600 entries, and additionally the author has compiled a long list of relevant web sites.
On balance, the book can be be considered as a personal, excellent and exhaustive overview of the state-of-the-art by one of the leading researchers in the field of parallel robots. Who ever wants to do research on parallel manipulators has to read this book first!
Reviewer: M.Husty (Leoben)


70-02 Research exposition (monographs, survey articles) pertaining to mechanics of particles and systems
70B15 Kinematics of mechanisms and robots
70E60 Robot dynamics and control of rigid bodies
68T40 Artificial intelligence for robotics