Torque Sensing Techniques for CMGs in DOB Configurations

This paper presents the disturbance torque sensation techniques of control moment gyroscope (CMG) actuators. A torque sensing task without torque sensors can be done by estimating the disturbance. Two torque sensation schemes are presented and their characteristics are compared in the configuration of a disturbance observer. One scheme is based on the linear model identification by the recursive least square (RLS) method. Another sensation scheme is based on the nonlinear model identification with the sigmoidal function. Experimental studies of two torque sensation schemes for CMGs are conducted to compare the performances between two schemes along with different implementation characteristics.