Dynamics and control of a bio-inspired Stewart platform

仿生抗冲击Stewart隔振平台的动力学与控制

¹ School of Astronautics, Northwestern Polytechnical University, Xi'an 710072, China
² National Key Laboratory of Aerospace Flight Dynamics, Xi'an 710072, China
³ Technology and Engineering Center for Space Utilization, Chinese Academy of Sciences, Beijing 100094, China

Received: 19 June 2020

Abstract

Collision and strong impacts take place in mission of the on orbit capture of non-cooperative spacecraft. So, it is necessary to design a vibration isolation system with efficient vibration isolation performance. A Stewart vibration isolation platform based on the bio-inspired isolation system is proposed in this paper. The characteristics of the novel bio-inspired Stewart platform realizes the vibration isolation protection of the serving spacecraft during the capture mission. The dynamic model of the vibration isolation platform is established by Lagrange's equations. The fidelity of the established dynamic model is verified via a comparison of the theoretical simulation and the ADAMS simulation. Comparisons between the presently proposed vibration isolation platform and the traditional spring-mass-damper type Stewart vibration isolation platform demonstrates the advantages of the present platform. The effects of system parameters on the isolation performance of the present platform are thoroughly investigated. The feedback linearization control method is used to control the present platform which overcomes the drift motion that occurs in the passive isolation case. The results show that the novel bio-inspired Stewart platform has excellent vibration isolation performance, which provides a promising way for the vibration isolation of the non-orbit capture mission.

摘要

空间非合作目标柔顺抓捕过程中伴随有碰撞、强冲击等问题，因此必须设计具有高效隔振性能的隔振系统。设计了基于仿生抗冲击结构的Stewart隔振平台，通过隔振平台的仿生抗冲击特性实现抓捕过程中服务航天器的隔振保护。隔振平台的理论动力学建模以拉格朗日动力学方程为基础，借助ADAMS软件验证了理论建模的正确性。仿真对比发现，设计的隔振平台的被动隔振性能优于基于线性弹簧阻尼隔振器的Stewart隔振平台。进一步研究了隔振平台参数对隔振性能的影响。采用反馈线性化的控制方法对隔振平台进行主动隔振控制，克服了被动隔振的速度漂移问题。研究表明设计的新型隔振平台具有优良的隔振性能，为非合作目标柔顺抓捕中的隔振系统选择提供了有效参考。