Six degrees of freedom adaptive finite-time control for spacecraft
approaching to a non-cooperative target
Abstract
The six degrees of freedom (6-DOF) adaptive finite-time control for
spacecraft with unknown uncertainties and disturbances approaching to a
non-cooperative target is investigated in this study. The system of the
spacecraft with coupled relative translation and relative rotation are
modeled. Considering the unknown mass and inertia uncertainties and the
state-dependent disturbances, a coupled 6-DOF adaptive finite-time
tracking control law with a self-adjustment function is developed to
achieve high precision proximity operations between chaser and
non-cooperative target. The convergence performance is improved by the
designed self-adjustment function. The unknown mass, inertia and
disturbance are estimated by adaptive update laws. The properties of the
proposed control law are discussed through the comparison of simulation
results.