Enhanced rapid attitude stabilization for space robots in postcapture using an iterated extended Kalman filter

Due to residual momentum, the space robot is tumbling after capturing an unknown target, like space debris because of the law of conservation of momentum. Therefore, it is essential to stabilize the attitude of the base for the objectives such as communication. In addition to the residual momentum and uncertainties in the inertial parameters of the target, the observation noise in real applications would degrade the stabilization performance or even lead to instability. To reduce the impacts of these factors, a novel strategy is presented in this paper for rapid attitude stabilization of space robots in postcapture. This approach exploits the dynamical coupling between the base and the manipulator to stabilize the attitude of the base with the limited control torque. In addition, to mitigate the effects of parameter and measurement uncertainties, an iterated extended Kalman filter is applied to estimate the motion state of the system and inertial parameters of the target in situations with state-dependent measurement noise. To verify the validity and feasibility of the presented approach, numerical simulations have been performed for the 2D and 3D models, and robustness and the effects of observation noise and initial velocity of the base have been analyzed via Monte Carlo simulations.