采用单框架控制力矩陀螺(SGCMG)作为主要执行机构,研究了挠性卫星的敏捷机动问题.首先,为挠性卫星建立带有时变参数及模型不确定性的刚柔耦合动力学模型;配置控制力矩陀螺/飞轮混合执行机构以满足敏捷卫星快速机动和高精度的任务需求.然后,设计积分型变结构控制律,并利用神经网络补偿器逼近不确定项,消除卫星挠性耦合特性和模型不确定性对系统的影响.最后,对算法进行了仿真验证.结果表明所设计的控制系统能够在执行机构不产生奇异的前提下,有效地抑制挠性附件的振动,使卫星在外界干扰及模型不确定性的影响下,快速达到要求的指向精度和稳定度.
Employing the single-gimbal control moment gyroscope(SGCMG) as the main actuator,this paper deals with the rapid maneuver problem of flexible satellite.Firstly,a rigid-flexible coupled dynamics model with variable parameters and model uncertainties is established for the flexible satellite,and the mixed actuator consisting of CMG and RW is configured for agile satellite to meet the requirements of rapid maneuver ability and high precision.Then,a variable structure control law of the integral type is designed with a neural network to estimate the uncertainties and eliminate their effects on the system.Finally,the proposed algorithm is validated by simulation.Simulation results show that under external disturbances and model uncertainties,the designed system could suppress vibrations of flexible appendages and achieve the pointing accuracy and high stable accuracy required rapidly without encountering singularities of the actuator.