针对挠性航天器系统中同时存在单框架控制力矩陀螺群(Single gimbaled control moment gyroscopes,SGCMGs)摩擦非线性、电磁干扰力矩、惯量摄动以及外部干扰等问题,提出了一种有限时间自适应鲁棒控制(Finite-time adaptive robust contr...针对挠性航天器系统中同时存在单框架控制力矩陀螺群(Single gimbaled control moment gyroscopes,SGCMGs)摩擦非线性、电磁干扰力矩、惯量摄动以及外部干扰等问题,提出了一种有限时间自适应鲁棒控制(Finite-time adaptive robust control,FTARC)方法.针对系统中存在未知参数的情况,分别设计自适应更新律,使得控制器的设计不依赖参数信息,同时减小外部干扰对系统的不利影响.应用Lyapunov稳定性理论证明了闭环系统姿态角误差和姿态角速度误差可在有限时间内收敛到原点附近的邻域内.仿真结果表明,所提控制律可实现挠性航天器姿态快速机动,并获得甚高指向精度.展开更多
Based on the singular value decomposition theory,this paper analyzed the mechanism of escaping/avoiding singularity using generalized and weighted singularity-robust steering laws for a spacecraft that uses single gim...Based on the singular value decomposition theory,this paper analyzed the mechanism of escaping/avoiding singularity using generalized and weighted singularity-robust steering laws for a spacecraft that uses single gimbal control moment gyros （SGCMGs） as the actuator for the attitude control system.The expression of output-torque error is given at the point of singularity,proving the incompatible relationship between the gimbal rate and the output-torque error.The method of establishing a balance between the gimbal rate and the output-torque error is discussed,and a new steering law is designed.Simulation results show that the proposed steering law can effectively drive SGCMGs to escape away from singularities.展开更多
框架转速控制精度是影响大型单框架控制力矩陀螺(Single Gimbal Control Moment Gyroscope,SGCMG)输出力矩精度的重要因素。谐波齿轮是一种大传动比的减速装置,在大型SGCMG框架伺服系统中加装谐波齿轮提高框架电机的转速,有利于减小框...框架转速控制精度是影响大型单框架控制力矩陀螺(Single Gimbal Control Moment Gyroscope,SGCMG)输出力矩精度的重要因素。谐波齿轮是一种大传动比的减速装置,在大型SGCMG框架伺服系统中加装谐波齿轮提高框架电机的转速,有利于减小框架转速控制偏差。本文分析了大型SGCMG框架电机和谐波齿轮传动的特性,建立了带有谐波齿轮的大型SGCMG动力学模型。数值仿真结果表明加装谐波齿轮可明显改善大型SGCMG框架转速控制精度,特别是框架低速运行时的控制精度,提高大型SGCMG输出力矩精度;但加装谐波齿轮也给框架带来高频谐振。展开更多
An improved constrained （IC） steering law for single gimbal control moment gyros （SGCMGs） with deformed pyramid configuration （DPC） is proposed, First of all, the original system with five pyramid configuration ...An improved constrained （IC） steering law for single gimbal control moment gyros （SGCMGs） with deformed pyramid configuration （DPC） is proposed, First of all, the original system with five pyramid configuration （FPC） whose two adjacent gyros are in failure state is reconfigured as a degraded system with DPC. Then, the singular angular momentum hypersurfaces of the original and the degraded systems are plotted via the singular angular momentum equa- tion of SGCMGs. Based on singular surfaces, the differences between FPC and DPC in singularity and momentum envelope are obtained directly, which provide an important reference for steering law design of DPC. Finally, an IC steering law is designed and applied to DPC. The simulation results demonstrate that the IC steering law has advantages in simplicity of calculation, avoidance of singularity and exactness of output torque, which endow the degraded system with fine controllability in a restricted workspace.展开更多
文摘针对挠性航天器系统中同时存在单框架控制力矩陀螺群(Single gimbaled control moment gyroscopes,SGCMGs)摩擦非线性、电磁干扰力矩、惯量摄动以及外部干扰等问题,提出了一种有限时间自适应鲁棒控制(Finite-time adaptive robust control,FTARC)方法.针对系统中存在未知参数的情况,分别设计自适应更新律,使得控制器的设计不依赖参数信息,同时减小外部干扰对系统的不利影响.应用Lyapunov稳定性理论证明了闭环系统姿态角误差和姿态角速度误差可在有限时间内收敛到原点附近的邻域内.仿真结果表明,所提控制律可实现挠性航天器姿态快速机动,并获得甚高指向精度.
基金supported by the National Natural Science Foundation of China (10872029)the Excellent Young Scholars Research Fund of the Beijing Institute of Technology (2007YS0202)
文摘Based on the singular value decomposition theory,this paper analyzed the mechanism of escaping/avoiding singularity using generalized and weighted singularity-robust steering laws for a spacecraft that uses single gimbal control moment gyros （SGCMGs） as the actuator for the attitude control system.The expression of output-torque error is given at the point of singularity,proving the incompatible relationship between the gimbal rate and the output-torque error.The method of establishing a balance between the gimbal rate and the output-torque error is discussed,and a new steering law is designed.Simulation results show that the proposed steering law can effectively drive SGCMGs to escape away from singularities.
文摘框架转速控制精度是影响大型单框架控制力矩陀螺(Single Gimbal Control Moment Gyroscope,SGCMG)输出力矩精度的重要因素。谐波齿轮是一种大传动比的减速装置,在大型SGCMG框架伺服系统中加装谐波齿轮提高框架电机的转速,有利于减小框架转速控制偏差。本文分析了大型SGCMG框架电机和谐波齿轮传动的特性,建立了带有谐波齿轮的大型SGCMG动力学模型。数值仿真结果表明加装谐波齿轮可明显改善大型SGCMG框架转速控制精度,特别是框架低速运行时的控制精度,提高大型SGCMG输出力矩精度;但加装谐波齿轮也给框架带来高频谐振。
基金supported by the National Natural Science Foundation of China (10372011)
文摘An improved constrained （IC） steering law for single gimbal control moment gyros （SGCMGs） with deformed pyramid configuration （DPC） is proposed, First of all, the original system with five pyramid configuration （FPC） whose two adjacent gyros are in failure state is reconfigured as a degraded system with DPC. Then, the singular angular momentum hypersurfaces of the original and the degraded systems are plotted via the singular angular momentum equa- tion of SGCMGs. Based on singular surfaces, the differences between FPC and DPC in singularity and momentum envelope are obtained directly, which provide an important reference for steering law design of DPC. Finally, an IC steering law is designed and applied to DPC. The simulation results demonstrate that the IC steering law has advantages in simplicity of calculation, avoidance of singularity and exactness of output torque, which endow the degraded system with fine controllability in a restricted workspace.
