Experiments of singularity avoidance steering control laws for redundant single-gimbal control moment gyros

Control moment gyros (CMGs) are actuators for agile spacecraft attitude control. The use of CMGs necessitates the development of CMG steering law. This article presents the results from experiments of singularity avoidance steering control laws based on the minimum two-norm, pseudoinverse solution, for redundant single-gimbal CMGs. Details of the experimental results are presented with discussion of experimental errors. The experimental results are compared with simulated results. Both results are used to verify the advantages of the singularity avoidance steering laws against the pseudoinverse solution by using a torque measurement facility composed of three major parts: vibration isolation system, dynamic force plate (Kistler sensor), and DSP board. The CMGs used to verify the steering laws are mounted on a typical pyramid configuration with skew angle of 57.9 deg and each CMG is able to produce a torque of 90 mNm.