Resolved Motion Rate Control of Space Robotic Manipulators with Generalized Jacobian Matrix

In recent years, space has attracted special interest as a new application field of robotics. A robotic teleoperator system installed with space manipulators will play an important role in future space projects, such as constructing space structures or servicing satellites. However, in space environment, the lack of a fixed base arises many problems in controlling space robotic systems. In general, any motion of the manipulator arm will induce reaction forces and moments which disturb position and attitude of the supporting base satellite. To establish a control method for space manipulators taking dynamical interaction between the manipulator arm and the base satellite into account, the authors investigate the kinematics of free-flying multi-jointed link systems by introducing the momentum conservation law into the formulation and derive a new Jacobian matrix in generalized form for space robotic arms. By means of the new matrix, they develop a control method for space manipulators based on the resolved motion rate control concept. The proposed method is widely applicable for not only free-flying manipulation problems but also attitude control problems. The validity of the method is demonstrated by computer simulations with a realistic model of robot satellite.