空间零重力地面模拟系统的滑模变结构控制

Sliding Model Variable Structure Control of Ground Simulation Test System for Spatial Microgravity Environment

针对做复杂运动的飞行器地面微重力试验环境模拟困难的问题,设计了一种新的空间微重力地面模拟系统。该系统采用剪式传动、轴承导向、电机驱动和气悬浮的组合方式来实现复杂运动微重力环境的模拟,通过力反馈控制方式来实时抵消目标的重力。首先建立系统动力学模型,考虑到试验目标本体等非线性驱动及模型本身的不确定及摩擦干扰,该控制策略采用滑模变结构控制来补偿非线性因素的影响,滑模面采用积分型切换函数从而降低了抖振,保证了系统的鲁棒性。实验结果表明,该地面试验装置对于三维空间微重力模拟能达到较高精度,且控制方法简单,易于实现,具有很高的工程应用价值。

A novel system was proposed to simulate the spatial microgravity environment for big and middle experimental objects with complex move. The equipments combine machine transmission,motor drive and air-bearing to realize threedimensional space microgravity simulation. Force feedback control aim gravity real timely as controller. Friction non-lin- earity of machine system and outside disturbance were considered. Sliding model controller was employed to reduce disturbance and uncertainty. The experimental results shows that ground test equipment has light weight, convenience using and higher precision, and compensates non-linearity infection, has important engineering value to three-dimensional space microgravity simulation.