卫星姿态的状态转移控制

本文面向卫星的应用需求,对卫星姿态的运动学和动力学进行了分析与建模.利用反馈线性化,将姿态运动的高阶非线性项包含在姿态控制中,通过局部动态线性化,将动力学系统近似为定常系统.通过幂级数法对系统进行了状态转移过程的求解.采用模型预测的方法获得姿态角和姿态角速度的预期偏差.通过广义逆变换构造关于偏差的最小范数、最小二乘控制器.提出了一种基于状态转移的卫星姿态机动、跟踪与稳定控制的新方法.控制器的参数具有根据系统采样周期和当前状态时变自适应的特点.考虑帆板挠性及多种偏差和噪声影响,仿真验证了方法的可行性和有效性.     

Modelling of flexible spacecraft and their stabilization†

The paper deals with the problem of rigorous modelling of flexible spacecraft and their stabilization. The attitude dynamics of the satellite bus and the equations for vibration of a flexible beam attached to it are derived. The complete system dynamics are given by a coupled set of ordinary and partial differential equations. The effects of controls applied on the. bus and/or on the flexible beam are investigated. It is shown that stabilization of the flexible spacecraft can be achieved by use of simple feedback controls.     

Asymptotic Smooth Stabilization of the Inverted 3-D Pendulum

The 3-D pendulum consists of a rigid body, supported at a fixed pivot, with three rotational degrees of freedom; it is acted on by gravity and it is fully actuated by control forces. The 3-D pendulum has two disjoint equilibrium manifolds, namely a hanging equilibrium manifold and an inverted equilibrium manifold. The contribution of this paper is that two fundamental stabilization problems for the inverted 3-D pendulum are posed and solved. The first problem, asymptotic stabilization of a specified equilibrium in the inverted equilibrium manifold, is solved using smooth and globally defined feedback of angular velocity and attitude of the 3-D pendulum. The second problem, asymptotic stabilization of the inverted equilibrium manifold, is solved using smooth and globally defined feedback of angular velocity and a reduced attitude vector of the 3-D pendulum. These control problems for the 3-D pendulum exemplify attitude stabilization problems on the configuration manifold SO(3) in the presence of potential forces. Lyapunov analysis and nonlinear geometric methods are used to assess global closed-loop properties, yielding a characterization of the almost global domain of attraction for each case.      

挠性卫星姿态非线性局部镇定控制

本文针对挠性卫星姿态机动和振动抑制问题,给出一种基于多项式平方和(sum of squares,SOS)的非线性局部镇定控制方法.根据姿态系统结构特征,在此基础上,采用SOS结合S-procedure理论,得出相应的非线性局部可镇定条件.该条件可借助有效凸优化工具进行检验,当优化问题可解时,可构造非线性姿态控制器的解析解.最后,将文中方法应用于某型挠性卫星姿态控制.仿真结果表明,在实现大角度姿态快速机动的同时,有效抑制了挠性附件振动.     

基于SIMULINK的卫星姿控系统的仿真实现

卫星姿态确定数学模型涉及到姿态敏感器系统、卫星姿态动力学与运动学原理以及数据处理方法,系统对象比较复杂。首先,基于欧拉角法和四元素法建立了微小卫星姿态运动学模型,基于相平而控制法建立了采用恒定推力的开关式控制的喷气姿态控制系统,随后,在MATLAB的Simulink交互式仿真集成环境中对模型进行仿真研究,验证了模型的有效性;最后,对卫星模型选取了适当的参数,仿真结果满足对定姿精度和姿态稳定度的要求,完成了模型的设计。为说明卫星姿态控制中相关的算法,文中介绍了simulink模块的结构框图。     

基于自适应模糊与输入输出线性化的卫星姿态控制

将自适应模糊控制与输入输出线性化控制相结合，构成混合控制器，并将其应用于挠性卫星的姿态机动控制．给出了卫星姿态控制器的基本形式，分析了控制器参数的选取准则．在线调节自适应模糊控制器的参数，以补偿不确定性卫星的姿态跟踪误差．仿真结果表明，该控制算法通过在线学习能有效地克服挠性卫星的不确定性，具有较强的鲁棒性，从而有效地提高了挠性卫星的姿态控制精度．     

空间太阳能电站的轨道、姿态和结构振动的耦合动力学建模及辛求解

作为一种从太空获得清洁能源的系统,空间太阳能电站(SPS)吸引着许多国家和科研机构的关注.由于其超大、超轻的柔性结构特点,研究其在轨动力学行为时需要考虑轨道、姿态和结构振动的耦合作用.本文在考虑地球的非球形摄动影响下,建立了集成对称聚光系统(ISC)的动力学模型.通过Legendre变换引入广义动量,在Hamilton体系下建立了其轨道、姿态、轴向振动耦合的动力学方程.采用辛Runge-Kutta方法对耦合动力学方程进行数值求解.根据数值结果,分别研究了其在地球同步轨道下二阶摄动项对轨道、姿态和结构振动的影响,并分析了总能量的变化情况.     

Asymptotic Stabilization of the Inverted Equilibrium Manifold of the 3-D Pendulum Using Non-Smooth Feedback

The 3-D pendulum consists of a rigid body, supported at a fixed pivot, with three rotational degrees of freedom; it is acted on by gravity and it is fully actuated by control forces. In , almost global stabilization of the inverted equilibrium manifold was studied using a smooth globally defined feedback. Here, we study the problem of almost global stabilization of the inverted equilibrium manifold using non-smooth feedback of angular velocity and a reduced attitude vector of the 3-D pendulum. The importance of the non-smooth feedback is that the almost global domain of attraction is a geometrically simple set that excludes the hanging attitude manifold. Unlike the closed-loop for a 3-D pendulum with a smooth controller, the closed-loop designed in this paper does not exhibit a performance constraint. These new results are based on Lyapunov analysis of the non-smooth closed-loop 3-D pendulum.      

存在飞轮安装偏差与故障的卫星姿态容错控制

基于滑模控制理论提出一种刚体卫星姿态稳定控制方法,实现对反作用飞轮部分失效故障的容错控制,以及对其安装偏差的补偿控制,并从理论上证明了所设计的控制器在有限时间内能够实现对闭环姿态控制系统的几乎全局渐近稳定控制.最后将所设计的控制器应用于某型卫星姿态稳定任务,仿真结果验证了所提出方法的有效性.     

Testing of attitude control algorithms for microsatellite “Chibis-M” at laboratory facility

A laboratory facility developed at the Engineering Technological Center “Scan Ex” for testing algorithms for determination of attitude and stabilization of the attitude system of the satellite “Chibis-M” is described. The results of experiments on damping initial angular rotation, using magnetorquers, stabilization of the mock-up using flywheels, and flywheel unloading are analyzed. The operation of the algorithm for determination of the mock-up attitude is studied; the main characteristics of this algorithm are the accuracy of the state vector estimation and the time of convergence.     

Two level attitude control for a television and broadcasting satellite

A two level method for the attitude control of a flexible communication satellite is described. Because of its great inertia the satellite is used as a platform for an antenna fine pointing control system while the satellite body is coarse controlled by jets. A simulation method is used which allows change of a satellite part without changing any other. Complex dynamic models are simplified while keeping the important characteristics. Simulation results are shown. Special forms of oscillations and resonance curves are analytically substantiated. The oscillations prove to be not dangerous. Changes of the solar generator natural frequency are not critical.     

姿态测量单元在船载卫星天线上的应用

提出了在船载卫星天线系统中,一种以姿态测量单元为核心的控制系统方案,详细叙述了该系统的三轴空间转动关系,推导出了如何由姿态测量单元输出的三维方向角进行天线反射面姿态修正的一系列数学表达式,介绍了进行前馈补偿的系统稳定方法;对系统进行摇摆试验测得方位角误差小于1.3°,俯仰角和横摇角误差小于0.5°;福州海关应用证明该系统能满足卫星通信稳定系统的技术要求。     

Studying the Possibility of Ensuring the Stabilization Accuracy Characteristics of an Advanced Spacecraft for Remote Sensing of the Earth

The possibilities of using of single-gimbal control momentum gyros (gyrodynes) in the control system of an advanced remote sensing satellite of the Earth are studied. The main difficulty arising in the phase of designing a composition of the motion control system for this satellite is that the gyrodynes currently produced in the Russian Federation have an angular momentum magnitude, considerably exceeding the value required for this satellite. The second circumstance is the limited range of the selected angular rate sensor, which hampers performing attitude maneuvers at high rates. Ways of solving these problems are considered and the possibility to ensure the required accuracies of stabilization in surveying the Earth’s surface is shown. The capability of this satellite to conduct areal and corridor surveys is demonstrated by the results of mathematical simulation.     

On the stabilization of a communication satellite without measuring its angular velocity

The motion control about the center of mass of the communication satellite Yamal-200 is considered. Due to possible failure of the angular velocity sensors, an algorithm for maintaining a prescribed attitude without measuring the angular velocity was developed for this satellite. The algorithm ensures the gyroscopic stabilization of the satellite motion about the local vertical. In the course of control, the onboard computer stores projections of the flywheels?? angular momentum vector on the axes of the inertial basis; the control system tries to preserve the angular momentum magnitude and direction in the inertial space based on the measurements of the angular momentum. The workability of the proposed stabilization algorithm was confirmed by flight tests.     

鲁棒镇定问题的H∞优化设计

将鲁棒镇定问题作为有约束的H∞优化问题来考虑.讨论了鲁棒镇定问题中的约束条 件和所要进行优化的性能指标.通过卫星姿态控制的算例具体说明了这种优化设计过程.     

三维物体识别及姿态测定的推理系统

本文介绍了三维物体识别及姿态测定的一种新技术，从物体空间域模型出发，通过约束推理及几何推理，在物体三维信息部分给定的条件下，推断预测图象模型，并通过实测的图象数据反馈，推断出隐含在图象中未给定的三维信息，最终实现三维物体识别及姿态测定。整个系统在ＶＩＣＯＭ机上用Ｃ语言完成。     

基于HLA的卫星姿态控制系统数学仿真

该文针对三轴稳定卫星的姿态控制系统，着重考虑重力、光压、大气、地磁对其姿态的影响，并对这些环境因素的力矩作用效果建模，利用所建模型对卫星具体构形进行计算，形成一个以飞轮作为主动力矩、通过磁力矩卸载的闭环稳定系统。整个系统在符合高层体系结构HLA标准的商业RTI——pRTI下，建立了SOM／FOM模型，实现了控制器、姿态力学和干扰力矩、管理者各联邦成员之间的信息传递以及仿真问的互操作，并促进了仿真资源的重用，最后对卫星姿态角随时问的变化进行了显示。     

Adaptive fuzzy sliding mode control for flexible satellite

The adaptive fuzzy sliding mode control is applied to the attitude stabilization of flexible satellite. The detailed design procedure of the fuzzy sliding mode control system is presented. The adaptive fuzzy control is utilized to approach the equivalent control of sliding mode control and the adaptive law is derived. The hitting control, which guarantees the stability of the control system, is developed. In order to attenuate the chattering phenomena, fuzzy rules are employed to smooth the hitting control. Simulation results show that precise attitude control is accomplished based on the proposed method.     

Adaptive control of rigid body satellite

The minimal controller synthesis （MCS） is an extension of the hyperstable model reference adaptive control algorithm. The aim of minimal controller synthesis is to achieve excellent closed-loop control despite the presence of plant parameter variations, external disturbances, dynamic coupling within the plant and plant nonlinearities. The minimal controller synthesis algorithm was successfully applied to the problem of decentralized adaptive schemes. The decentralized minimal controller synthesis adaptive control strategy for controlling the attitude of a rigid body satellite is adopted in this paper. A model reference adaptive control strategy which uses one single three-axis slew is proposed for the purpose of controlling the attitude of a rigid body satellite. The simulation results are excellent and show that the controlled system is robust against disturbances.     

自由漂浮空间机器人的笛卡尔连续路径规划

对于自由漂浮空间机器人,位置级逆运动学方程不适合于笛卡尔连续路径的规划,而且机械臂的运动会对基座产生扰动.为此提出了基于速度级逆运动学方程的方法,可实现5个目标:1)惯性空间连续位姿跟踪;2)基座姿态无扰动的连续位置跟踪;3)基座姿态无扰动的连续姿态跟踪;4)基座姿态调整的连续位置跟踪;5)基座姿态调整的连续姿态跟踪.采用阻尼最小方差法回避动力学奇异,所规划的路径连续平滑.仿真结果表明了该方法的有效性.