Kinematic control of redundant free-floating robotic systems

This paper is aimed at presenting solution algorithms to the inverse kinema tics of a space manipulator mounted on a free-floating spacecraft. The reac tion effects of the manipulator's motion on the spacecraft are taken into a ccount by means of the so-called generalized Jacobian. Redundancy of the sy stem with respect to the number of task variables for spacecraft attitude a nd manipulator end-effector pose is considered. Also, the problem of both s pacecraft attitude and end-effector orientation representation is tackled b y means of a non-minimal singularity-free representation: the unit quaterni on. Depending on the nature of the task for the spacecraft/manipulator syst em, a number of closed-loop inverse kinematics algorithms are proposed. Cas e studies are developed for a system of a spacecraft with a six-joint manip ulator attached.