Understanding and Utilizing Dynamic Coupling in Free-Floating Space Manipulators for On-Orbit Servicing

TL;DR

This paper introduces a novel trajectory optimization method for free-floating space manipulators that leverages dynamic coupling rather than minimizing it, leading to more efficient on-orbit servicing operations.

Contribution

It presents a dynamic coupling-informed trajectory optimization framework using SVD and a new metric, enhancing control strategies for space manipulators.

Findings

Optimized trajectories improve system efficiency.

Explicit coupling consideration enhances control accuracy.

Simulation confirms the effectiveness of the proposed method.

Abstract

This study proposes a dynamic coupling-informed trajectory optimization algorithm for free-floating space manipulator systems (SMSs). Dynamic coupling between the base and the manipulator arms plays a critical role in influencing the system's behavior. While prior research has predominantly focused on minimizing this coupling, often overlooking its potential advantages, this work investigates how dynamic coupling can instead be leveraged to improve trajectory planning. Singular value decomposition (SVD) of the dynamic coupling matrix is employed to identify the dominant components governing coupling behavior. A quantitative metric is then formulated to characterize the strength and directionality of the coupling and is incorporated into a trajectory optimization framework. To assess the feasibility of the optimized trajectory, a sliding mode control-based tracking controller is designed to generate the required joint torque inputs. Simulation results demonstrate that explicitly accounting for dynamic coupling in trajectory planning enables more informed and potentially more efficient operation, offering new directions for the control of free-floating SMSs.