Passivity-Based Adaptive Finite-Time Trajectory Tracking Control for Spacecraft Proximity Operations

A passivity-based robust adaptive finite-time trajectory tracking control strategy is developed for a pursuer spacecraft proximity to a cooperative target spacecraft in space. The relative position vector between the pursuer and the target is required to direct toward the docking port of the target while the attitude of the two bodies must be synchronized. With the effective reference trajectory, the finite-time control of relative translational and relative rotational motions is finished simultaneously by using a unified passivity-based adaptive control method. Finite-time stability of the closed-loop system for six degree-of-freedom relative motion is proved in spite of the unknown inertial parameters and external disturbances. Numerical simulations including six-degree-of-freedom rigid-body dynamics are performed to demonstrate the effectiveness of the proposed controller.