An adaptive variable structure control of the robot satellite system with floating base in Cartesian space

Abstract

Aiming at the non-parametric and time-varying parametric uncertainty problems such as the external disturbances, smooth parameter variations and jump parameter changes existing in the robot satellite system with floating base, an adaptive variable structure trajectory tracking control method in Cartesian space is proposed. The dynamics equation in joint space of the robot satellite system with floating base is established based on the extended manipulator model, and the dynamics model of the system in Cartesian space is derived considering external disturbances to the manipulator and the base simultaneously. An adaptive variable structure controller is designed by adopting the composite adaptive control combined with variable structure control under the condition that the bounds of external disturbances and parameter variations are unknown, and the robustness analysis of the controller is performed. The simulation of a two-link planar robot satellite system with floating base adopting the control method presented is implemented. The simulation result shows that the end-effector of the robot satellite with floating base has a good capability of trajectory tracking in Cartesian space.

Multi-segment trajectory tracking of the redundant space robot for smooth motion planning based on interpolation of linear polynomials with parabolic blend

“…8 In the literature, numerous approaches and tactics for trajectory planning for a free-floating space manipulator have been proposed. Zhang et al 9 proposed motion control of free-floating space manipulator through the adaptive controller in Cartesian space. Liu et al 10 proposed timeoptimal and jerk-optimized motion planning of space robots through a combination of cubic spline in Cartesian space and B-spline in joint space.…”

Dynamic behavior and parameter sensitivity of the free-floating base for space manipulator system considering joint flexibility and clearance

“…However, unlike the terrestrial manipulators, a free-floating space manipulator system (FFSMS) is always free from the influence of external force, which leads to that the spacecraft base is permitted to translate and rotate freely in response to manipulator motions. To accomplish space missions successfully, it is desirable that the kinematic accuracy and stability of the spacecraft base for free-floating space manipulator system can be controlled well in the operation process, [3][4][5] so it is especially important to have an overview about the dynamic characteristics of the spacecraft base for free-floating space manipulator system.…”