Reactionless space and ground robots: novel designs and concept studies

For conventional designs of space and earth robots, manipulator motions result in forces and moments on the base. These forces and moments cause translation and rotation of the free-floating base of a space robot. For earth robots, the same forces and moments get transmitted to the base and may cause undesirable base excitations. The objective of this paper is to systematically analyze the fundamentals of reactionless space and earth robots. Based on this analysis, design of two distinct classes of planar robots is proposed, with appropriate choices of geometric and inertial parameters. Due to underlying principle of conservation of angular momentum for these special robots, the trajectory must satisfy additional constraints. We illustrate the reactionless feature of these robots and trajectory planning of these robots through computer simulations. Currently, we are fabricating such reactionless robots to illustrate the underlying concepts.