Abstract: The torque/angular momentum saturation due to the output limitation of the reaction wheel is adverse to the attitude maneuver performance of the spacecraft. To deal with this problem, torque distribution and angular momentum management is investigated for the spacecraft with a redundant reaction wheel array. Firstly, according to the inertia parameters and the expected maneuver direction of the spacecraft, angular momenta of reaction wheels and the maximum spacecraft slew angular rate are determined from the system momentum at the intersection of the angular momentum envelope along its varying direction．Secondly, the maximum slew torque available is derived by use of the desired angular momentum rate, which is devised to be in proportion to the variation of the angular momentum with its L∞-norm satisfying the torque constraint. Then, a novel torque distribution algorithm is developed by minimizing a quadratic function of the deviation between the angular momentum varying rate and its expected value, making the angular momentum envelope accessible. Finally, numerical simulations are executed with the proposed scheme as well as the L2 and L∞ torque distribution methods when the same maneuver torque requirement is provided. By the selection of the maximum angular rate/acceleration and the torque distribution law, the attitude maneuver in an arbitrary direction can be achieved to the best of ability, significantly improving the agility and autonomy of the spacecraft.

Key words: attitude maneuver；reaction wheel；momentum envelope；torque distribution algorithm, momentum management