Relative Motion Dynamics Modeling and Control of DFP Vibration Isolation Spacecraft

基于螺旋理论的DFP隔振航天器相对运动动力学建模与姿轨耦合控制

¹ School of Astronautics, Northwestern Polytechnical University, Xi’an 710072, China
² National Key Laboratory of Aerospace Flight Dynamics, Xi’an 710072, China

Received: 10 September 2018

Abstract

In order to better meet the future high precision task requirements, the DFP(Disturbance-Free Payload) spacecraft composed of non-contact PM(Payload Module)and SM(Support Module)is taken as the object to study the relative motion dynamics modeling and control between the two modules and verify the system vibration isolation performance. Firstly, the force and torque expressions of the two modules are derived by simplifying the configuration and analyzing the stress. In view of that couple effect, the relative motion dynamics equations between two modules of DFP spacecraft with high model accuracy, and simple and uniform format are established with the dual quaternions. Based on this, the PD control law is designed, and the relative motion of PM and SM could meet DFP spacecraft working requirements when the measurability of control quantity and the measurement error of sensors were taken into account. Simulation results verify the advantage of vibration isolation and attitude maneuverability of DFP spacecraft.

摘要

为更好满足未来高精度任务要求，以由无接触的有效载荷模块（payload module，PM）和支持模块（support module，SM）组成的DFP（disturbance-free payload）航天器为对象，开展两模块间的相对运动动力学建模与控制研究和系统隔振性能验证。首先通过简化构型、梳理受力情况，重点推导了两模块所受力和力矩表达式；其次考虑耦合效应，利用对偶四元数建立了模型精度更高且形式简洁统一的DFP航天器两模块间的相对运动动力学方程；在此基础上设计PD控制律，考虑控制量可测性及敏感器测量误差，使PM和SM的相对运动满足DFP航天器工作要求。仿真结果验证了DFP航天器的隔振优势和姿态机动性能。