In remote sensing or laser communication space missions,spacecraft need fast maneuver and fast stabilization in order to accomplish agile imaging and attitude tracking tasks.However,fast attitude maneuvers can easily cause elastic deformations and vibrations in flexible appendages of the spacecraft.This paper focuses on this problem and deals with the combined control of fast attitude maneuver and stabilization for large complex spacecraft.The mathematical model of complex spacecraft with flexible appendages and momentum bias actuators on board is presented.Based on the plant model and combined with the feedback controller,modal parameters of the closed-loop system are calculated,and a multiple mode input shaper utilizing the modal information is designed to suppress vibrations.Aiming at reducing vibrations excited by attitude maneuver,a quintic polynomial form rotation path planning is proposed with constraints on the actuators and the angular velocity taken into account.Attitude maneuver simulation results of the control systems with input shaper or path planning in loop are separately analyzed,and based on the analysis,a combined control strategy is presented with both path planning and input shaper in loop.Simulation results show that the combined control strategy satisfies the complex spacecraft’s requirement of fast maneuver and stabilization with the actuators’torque limitation satisfied at the same time.
控制力矩陀螺群(Control moment gyroscopes,CMGs)作为姿态控制执行机构被广泛应用,但是自身的高频振动特性直接影响星体的姿态精度和稳定度。为能有效地提高星体的姿态精度和稳定度,通过使用六自由度隔振平台处理CMGs产生的高频振动,并对隔振平台的应用进行多任务要求下的协调性研究。建立含有隔振系统和挠性帆板的整星动力学模型,通过对模型的合理简化,得出隔振平台的传递函数特性;分析其和姿态控制系统以及挠性部件相互之间的影响,并得到隔振平台参数设计的约束指标;根据约束指标对隔振平台重要参数进行理论上的设计,并通过数值仿真验证所设计参数的合理性;将所设计的隔振平台运用到整星中,对整星姿态精度和稳定度进行预测,以分析加入隔振平台后,对整星姿态控制精度和稳定度的影响。
