Momentum equalization control of space robot with control moment gyroscopes for joint actuation

An angular momentum equalization control method was proposed for redundant space robot with scissored-pair control moment gyroscopes (CMGs) for joint actuation. This method utilizes the space robot's extra degrees of freedom to equalize momentum usage among arm links, thus achieving CMGs' simultaneous saturation and better trajectory tracking ability. A momentum equalization index was defined following the idea of equal momentum usage to achieve simultaneous CMGs saturation. A control technique was developed based on acceleration-level redundancy resolution and inverse dynamics control, with precious operational space tracking ability and momentum equalization index local minimization functionality. The local minimization of momentum equalization index serves as a means to use angular momenta as equally as possible, which decreases the possibility of non- simultaneous saturation and takes full advantage of the CMGs'angular momentum capacity. A planar three degree-of-freedom redundant manipulator was used in numerical simulation to verify the effectiveness of the control technique.