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
The steering laws of single gimbal control moment gyros （SGCMGs） are analyzed and compared in this paper for a spacecraft attitude control system based on singular value decomposition （SVD） theory. The mechanism o...The steering laws of single gimbal control moment gyros （SGCMGs） are analyzed and compared in this paper for a spacecraft attitude control system based on singular value decomposition （SVD） theory. The mechanism of steering laws escaping singularity, especially how the steering laws affect singularity of gimbal configuration and the output torque error, is studied using SVD theory. Performance of various steering laws are analyzed and compared quantitatively by simulation. The obtained results can be used as a reference for designers.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
针对五棱锥单框架控制力矩陀螺群(Single gimbaled control moment gyroscopes,SGCMGs)中存在的奇异问题,建立五棱锥构型SGCMGs系统动力学模型,基于双曲正弦函数和分段函数设计鲁棒系数,改进鲁棒伪逆操纵律,使SGCMGs系统在处于奇异状态...针对五棱锥单框架控制力矩陀螺群(Single gimbaled control moment gyroscopes,SGCMGs)中存在的奇异问题,建立五棱锥构型SGCMGs系统动力学模型,基于双曲正弦函数和分段函数设计鲁棒系数,改进鲁棒伪逆操纵律,使SGCMGs系统在处于奇异状态时,保证框架角速度不为零,从而逃离奇异;在接近奇异状态时迅速避开奇异,在远离奇异状态时更精确地输出期望力矩。通过SGCMGs不同类型力矩输出和挠性航天器大角度姿态机动控制的仿真结果表明,所提SGCMGs操纵律既能够较好地规避奇异状态,又能在远离奇异时精确地输出期望力矩。展开更多
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.
基金the National Natural Science Foundation of China(No.10502006)the ExcellentScholars Fund of Beijing(No.20071D1600300398)the Excellent Young Scholars Research Fundof Beijing Institute of Technology(No.2007YS0202)
文摘The steering laws of single gimbal control moment gyros （SGCMGs） are analyzed and compared in this paper for a spacecraft attitude control system based on singular value decomposition （SVD） theory. The mechanism of steering laws escaping singularity, especially how the steering laws affect singularity of gimbal configuration and the output torque error, is studied using SVD theory. Performance of various steering laws are analyzed and compared quantitatively by simulation. The obtained results can be used as a reference for designers.
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.
文摘针对五棱锥单框架控制力矩陀螺群(Single gimbaled control moment gyroscopes,SGCMGs)中存在的奇异问题,建立五棱锥构型SGCMGs系统动力学模型,基于双曲正弦函数和分段函数设计鲁棒系数,改进鲁棒伪逆操纵律,使SGCMGs系统在处于奇异状态时,保证框架角速度不为零,从而逃离奇异;在接近奇异状态时迅速避开奇异,在远离奇异状态时更精确地输出期望力矩。通过SGCMGs不同类型力矩输出和挠性航天器大角度姿态机动控制的仿真结果表明,所提SGCMGs操纵律既能够较好地规避奇异状态,又能在远离奇异时精确地输出期望力矩。
