变速控制力矩陀螺(VSCMG)是一种飞轮转速可变的单框架控制力矩陀螺,可工作在控制力矩陀螺(CMG)模式、飞轮(RW)模式以及VSCMG模式.考虑VSCMG的工作特点,设计一种工作模式自主调度的操纵律.当系统远离奇异时,仅以CMG模式工作,产生大的输出力矩.当系统接近奇异时,以VSCMG模式工作,采用RW协助CMG回避奇异.当航天器处于姿态稳定模式需要精细控制力矩时,仅以RW模式工作.该操纵律由模式调度策略、CMG操纵律、RW操纵律3部分组成,把一个3×2N矩阵的求伪逆问题转化为两个3×N矩阵的求伪逆问题,物理意义明显,奇异回避易于实现.对某4-VSCMG系统的仿真结果表明,上述操纵律是可行的.
Variable speed control moment gyroscope(VSCMG) is a single-gimbal control moment gyroscope(CMG) with an adjustable speed of the wheel,and has three work modes,i.e.,CMG mode,reaction wheel(RW) mode,and VSCMG mode.In order to command VSCMGs to work in suitable mode,a mode-scheduling steering law is presented.When CMGs are far from the singularities,the CMG mode can be used to generate large output torque.Otherwise,VSCMG mode can be used to escape from the singularities with the help of RWs.When accurate control torque is needed,RW mode can be used.This algorithm has obvious physical meanings and is easy to realize because the pseudo-inverse problem of a 3×2N matrix is decomposed into the pseudo-inverse problem of two 3×N matrices.Simulation results for a certain VSCMG system demonstrate that the steering law presented above is feasible.