An efficient dynamic modeling and simulation method of a cable-constrained synchronous rotating mechanism for continuum space manipulator

Abstract

Continuum space manipulators have advantages in working in the confined spaces to conduct some fine operating tasks for high-value malfunctioning satellites, while Cable-Constrained Synchronous Rotating Mechanism (CCSRM) is a new mechanical structure for continuum manipulators to improve their stiffness and reduce the motor numbers. However, the dynamic equations of manipulators with CCSRM have stiff problems, which reduce the calculation efficiency. This paper proposes an efficient dynamic modeling and simulation method for continuum space manipulators with CCSRM. The rotations of rigid links of the manipulator are described by quaternion parameters, and the dynamic equations of the system are obtained by using Lagrange equations of the first kind. The connecting cables of the CCSRM are modeled by linear torsional spring-dampers. The stiff problems are modified by a model smoothing method to reduce the high-frequency components of the motion, after which a relatively much larger integration step can be taken, which can significantly improve the calculation efficiency. Finally, two numerical examples are provided as demonstrative applications. The numerical results show that the proposed method can improve the calculation efficiency by two or three orders of magnitude and realize real-time simulation.