Affiliation:
1. City University of Hong Kong Department of Manufacturing Engineering and Engineering Management Kowloon, Hong Kong
2. Xidian University School of Electro-Mechanical Engineering Xi'an, People's Republic of China
Abstract
A macro-micro manipulators system consists of a large parallel cable manipulator and a fine tuning Stewart platform, is used to implement the high-precision trajectory tracking of the feed for the square kilometre array (SKA). The dynamic coupling between the two subsystems degrades the tracking precision seriously. An active suppression strategy of this dynamic coupling is proposed in this paper, using the controllable field-dependent damping force of an electrorheological (ER) damper to counteract the reaction forces of the fine-tuning Stewart platform. The reaction forces acting on the base platform is derived first, and the induced vibration is analysed using the finite element method. The design of the proposed ER damper is developed, followed by establishment of the relationship between the controllable damping force and the required voltage. The feasibility of this dynamic coupling suppression strategy is verified by numerical simulations, which has built a solid base for the engineering implementation of the high-precision tracking of the feed for the SKA.