Attitude Control of an Underactuated Satellite Using Two Reaction Wheels

摘要

A controller was introduced that uses only two reaction wheels in order to deal with the case of failure of one of three of them. The controller has a parameter that allows consideration of the effect of the derivative of the unactuated component on the other ones. To analyze the tuning effect for this extra parameter, the controller was compared with two tuning situations, one of which reduces to a well-known controller of the literature (SNLC). Compared to the SNLC, simulations show that the proposed algorithm, for situations with saturation, external disturbances, and noisy measurements, may diverge at the beginning of the transitory response and slightly increase the torque required to maintain an attitude in order to significantly reduce the system settling time and steady-state error. Also, the overall integrated torque comparison shows that some performance enhancement is obtained with some savings in the integrated torque.