Algorithm for simultaneous attitude maneuver and momentum dumping

Abstract

A system and method are disclosed for simultaneous attitude maneuver and momentum dumping. The attitude maneuver is performed using nominal wheel control to minimize propellant usage, while applying a momentum management command to the thruster control loop in order for the wheels to accomplish the desired spacecraft maneuver while simultaneously being reset to a de-saturated target state. The system and method involve a wheel system comprised of reaction wheels and/or a control moment gyroscope (CMG), at least one thruster, and control logic that is in communication with the wheel system and thruster(s). If a spacecraft maneuver is in progress, the control logic biases an error input signal to a thruster control loop to track the wheel maneuver to prevent unnecessary propellant consumption. The control logic is further operable to output thruster torque commands and wheel torque commands that accomplish the maneuver while achieving the desired final momentum target.