【作者】 叶东；

【导师】 孙兆伟；

【作者基本信息】 哈尔滨工业大学 ， 航空宇航科学与技术， 2013， 博士

【摘要】 随着航天技术的发展，对特定目标长时间凝视、单线阵相机立体成像为代表的航天任务都要求卫星具有敏捷性。姿态敏捷性包括姿态快速机动、姿态快速稳定以及机动过程中保持稳定三种能力，不同的任务对卫星敏捷性有不同的要求。根据上述特殊性，本学位论文着重围绕时间最优姿态机动轨迹规划、推力器-飞轮和控制力矩陀螺-飞轮的联合控制算法和柔性敏捷卫星的控制问题展开深入研究，主要内容包括以下几个部分：敏捷卫星时间最优姿态机动轨迹设计。基于配点法求解出时间最优姿态机动轨迹，并得到时间最优姿态机动控制力矩相继控制切换的性质。在忽略陀螺力矩项的前提下，推导了终端角速度为零所需要满足的条件，并结合运动学方程的近似解，提出了一种计算效率很高的准时间最优的轨迹规划方法，并对计算不准确所带来的机动残差提出了快速末端校正方法。最后，在不增加计算量的情况下，提出使用自动学习机优选粒子群算法并求解得到准确的控制切换时间。推力器与飞轮的联合执行机构控制策略。针对对地观测敏捷卫星大角度快速机动、高控制精度的任务需求，提出了联合推力器与飞轮作为执行机构的控制策略，为补偿初始状态偏差和推力器输出力矩不准确所带来的控制误差，基于变结构控制和自适应控制设计了两种姿态跟踪控制器。在不损失姿态机动控制精度的前提下，对机动过程中飞轮力矩及转速可能出现的饱和问题提出了相应的修正方法。控制力矩陀螺与飞轮的联合执行机构控制策略。针对控制力矩陀螺与飞轮联合执行机构控制过驱动问题，在建立通用动力学模型基础上，设计了包括控制力矩陀螺奇异性指数和与转速有关能量的优化目标函数，基于受约束的优化方法提出了控制分配方法。通过合理的调整权重参数，有效地解决了控制过程中飞轮转速饱和以及控制力矩陀螺奇异性等问题。针对控制力矩陀螺和飞轮的安装偏差对控制精度的影响，基于多输入输出自适应控制理论设计了跟踪控制器，并采用平滑映射原理保证参数更新不会使跟踪控制律出现奇异现象。柔性敏捷卫星快速机动稳定控制算法研究。针对单轴敏捷柔性卫星的快速机动稳定控制问题，将输入成形和反馈控制联合应用于柔性附件的振动抑制，形成主动振动抑制策略。同时为了降低柔性附件模态变量以及外界干扰的影响，所设计的反馈控制器只涉及姿态信息，并在此基础上根据整个闭环系统的振动频率和阻尼比信息完成前馈鲁棒多模态输入成形器设计。针对三轴敏捷柔性卫星姿态快速机动的控制问题，设计了一种仅利用卫星本体姿态角度和姿态角速度观测信息的变结构跟踪控制器，并对控制器的稳定性进行了严格的数学证明。该控制器使得姿态状态跟踪误差以及挠性附件的模态变量从任意的初始状态出发都会到达包含原点的一个闭集内。更多还原

【Abstract】 With the development of aerospace technology, satellites are required to possessagility in numbers of aerospace missions, such as long-time staring-imaging of aspecific ground target and stereo-imaging with single-line-array CCD camera. Theagility of satellites means that satellites are provided with the ability to accomplish theattitude maneuver rapidly, stabilize the attitude quickly and keep high stability duringfast attitude maneuver. The flying missions differ in the demand to agility of satellites.According to the aforementioned features, this dissertation deeply studies time-optimaltrajectory planning problem, hybrid control strategy with mixed thruster-flywheel andmixed CMG-flywheel, and control method for a flexible agile satellite. The researchcontents of this dissertation are presented as follows:Design of time-optimal attitude maneuver trajectory for agile satellites. Thetime-optimal trajectory is calculated based on collocation method, and properties ofsequential control switching for time-optimal attitude trajectory are obtained. Byignoring gyro torques, conditions which terminal angular velocity being zero requiresare derived, followed by proposing of the quasi-time-optimal attitude maneuvertrajectoy with high computing efficiency. And then a fast end correction method forterminal maneuver errors as a result of calculation inaccuracy is proposed. Finally,Learning Automata is utilized to tune the parameters of particle swarm algorithmwithout increasing computational cost and the accurate switching time is calculaterd bythe proposed method.Hybrid thrusters and reaction wheels control strategy. In order to solve the fastlarge-angle attitude maneuver and high-accuracy control problem for earth observationagile satellite flying mission, a control strategy by combining thrusters and flywheels isproposed. So as to compensate initial states errors and control torques inaccuracy ofthrusters, two kinds of attitude tracking control laws by utilizing variable structurecontrol and adaptive control theory are designed. Without reducing accuracy of attitudemaneuver control, a revising approach dealing with the saturate problem of flywheel’srotation and torques in attitude maneuver is proposed.Hybrid CMGs and reaction wheels control strategy. In view of the overactuatedproblem of combing CMGs and reaction wheels control strategy, based on generaldynamic model of variable speed CMGs, an optimization objective function related toCMG singularity index and energy-like rotation rate is designed, and then a controltorques distribution method based on constrained optimization method is proposed. Byadjusting weight parameters properly, the flywheel rotation rate saturation and CMGsingularity problems during the control process are solved. Since the installation error of CMG and flywheel could affect the control accuracy, a tracking control law based onMIMO adaptive control theory is proposed, and the updating of parameters will notcause the singularity of the tracking control law by using smooth projector principle.Research on fast maneuver and stabilization control method for agile flexiblesatellite. For the problem of fast maneuver and stability control of uniaxial agile flexiblesatellite, the combination control strategy based on input shaping and feedback controlis proposed. Considering that the modal variables of flexible appendages are hard to bemeasured and there always exists external disturbance torques, the controller which onlyuses the attitude information is designed. Moreover, according to the vibrationfrequency and the damping ratio of the closed-loop system, a feed-forward robustmulti-mode input shaping control approach is designed. For the problem of the fastmaneuver control of triaxial agile flexible satellite, a variable control method whichonly uses the attitude angle and attitude angular velocity is proposed, and the stability ofthe controller is proved by strict mathematical proof. The proposed variable controllercan drive the attitude state tracking error (including attitude tracking error and attitudeangular velocity tracking error) and the modal variables of flexible appendages from anarbitrary initial state to a neighborhood including the origin.更多还原