参数不确定SGCMG系统的自适应操纵律设计

在单框架控制力矩陀螺(SGCMG)系统操纵律的设计中,如果考虑框架伺服特性,往往假设系统的物理参数是确切已知的.为消除参数的不确定性对操纵性能的影响,设计了一种自适应操纵律.该操纵律可对系统物理参数进行在线估计,并能根据航天器姿态控制给出的角动量(或力矩)指令,直接计算出每个框架驱动系统所需的控制力矩.由于操纵律没有算法奇异,在SGCMG系统不出现运动奇异的情况下,可使操纵误差渐近收敛至零.同时,该操纵律对系统参数变化具有良好的适应性,且形式简单,易于实现.对应用在航天器上的某SGCMG系统的仿真结果表明,上述操纵律是可行的.

Adaptive steering law design for single gimbal control moment gyroscopes with parameter uncertainty

Physical parameters of single gimbal control moment gyroscopes(SGCMGs) are often assumed to be known exactly when steering law is designed by taking gimbal servo characteristics into account.However,exact physical parameters are not available due to system complexity.In order to reduce the effect of parameter uncertainty on steering performance,an adaptive steering law is presented.This steering law can estimate physical parameters on line and calculate the control torque for each SGCMG gimbal directly according to the momentum(or torque) command.Since it has no arithmetic singularity, steering error can be made converge to zero asympotically when kinematic singularities do not appear.Meanwhile,the steering law is guaranteed to have excellent adaptability to parameter variations.Comparatively,it has a simple form and is easy to be implemented.Simulation results of a SGCMG system indicate that steering law stated above is feasible.