【作者】 刘强；

【导师】 张峰； 何欣；

【作者基本信息】 中国科学院研究生院（长春光学精密机械与物理研究所） ， 光学工程， 2013， 博士

【摘要】 航天遥感多光谱成像技术是空间遥感卫星的核心技术之一，由于其应用需求的广泛性，各航天大国都投入了极大的研究力度。我国在多光谱成像遥感技术上也进入到了实用阶段。空间遥感器是航天遥感的主要设备，随着用户对光学遥感器的不同需求，空间遥感器朝向两个方面发展，一方面需求是地面分辨率，另一方面需求是对地成像覆盖宽度。论文要研究的空间遥感器就是为了满足宽覆盖成像要求而研制的。本文研究的空间多光谱超宽覆盖遥感器的幅宽超过1000km，为了满足遥感器的结构稳定性及光学成像质量要求，对遥感器的底部支撑组件进行了设计，使其能满足相应的动、静态刚度要求。对超宽覆盖遥感器的特点及其对结构设计带来的难点进行了分析，超宽视场遥感器结构形式为大宽长比，外形尺寸宽长比接近1.5:1，因此在设计时采取传统的结构形式和设计手段难以满足光学系统的成像质量要求，同时由于整机重量要求比较严格，要求设计余量非常小，即遥感器结构设计时结构更紧凑、要求精度更高，如许多其它遥感器上可以用线性近似代替非线性计算的设计理念不能再采用了，从而提高了结构设计的难度。明确了设计目标，本文的研究工作是针对遥感器的底部支撑机构设计展开的，内容分为基于运动学底部支撑方案分析、支撑机构对遥感器的指向精度影响分析、支撑机构保证遥感器成像质量分析、支撑机构的动态特性分析以及遥感器整机静力学动力学试验五大部分。首先对底部支撑机构的支撑方案进行设计，对比了目前空间遥感器常用的刚性支撑、柔性支撑及运动学支撑方式各自的优缺点及应用场合，结合宽幅盖遥感器的结构特点选择了运动学支撑，并针对不同运动学支撑方案进行详细分析，最终确定底部支撑选用2-RRR+2-RRRR并联机构。其次确定了底部支撑机构的安装位置，分析了底部支撑机构对超宽覆盖遥感器的光学指向精度的影响程度，通过机构等效、并联机器人工作空间分析等手段，计算出了底部支撑组件对遥感器指向精度影响，即在特定的间隙值下绕X、Y、Z三个方向的最大角量分别是2.6"、2.1"、2.3"，满足指向精度要求；再次引入了接触理论，通过非线性有限元分析了由转动运动副组成的底部支撑机构的平台适应性，通过计算结果对卫星平台的平面度提出了要求；同时对底部支撑机构的热适应性做了分析，分析结果表明底部支撑机构具有很好的热适应性，在遥感器与外界温差在20℃时仍然可以保持良好的光学成像质量；然后对底部支撑机构的动力学特性进行了分析，通过对含间隙的运动支撑模型进行计算分析，得出了底部支撑机构转动副间隙的存在对有限元分析机构的模态及响应的误差非常小，分析时可以不考虑间隙；对底部支撑机构的响应特性采用MPC的计算方式进行了分析计算，同时进行了组件级的力学试验，分析结果和试验结构相吻合，均满足设计要求；最后对超宽覆盖多光谱遥感器进行了静力学和动力学试验，静力学试验包括平台平面度适应性试验、温度拉偏试验；动力学试验包括正弦振动试验和随机振动试验。静力学试验和动力试验前后，遥感器的光学成像质量始终保持良好，说明底部支撑机构设计是成功的。更多还原

【Abstract】 Space remote sensing multispectral imaging technology is one of the coretechnologies of space remote sensing satellite. Various countries have invested greatefforts in the researches because of the wide range of its application requirements.Multispectral imaging remote sensing technology in China has entered into thepractical stage. Space remote sensor is the major equipment for aerospace remotesensing satellite. Space remote sensor gets two development directions with theusers’ different requirements of optical remote sensor. One is the ground resolution;another is the coverage width earth imaging. The space remote sensor researched inthe thesis is developed in order to meet the requirement of the wide coverage ofimaging.The coverage width of the space multispectral ultra-wide remote sensors in thisthesis is more than1000km. An optimization design was carried out on the bottomsupport assembly of the remote sensor, in order to meet the requirements of thestructural stability and optical imaging quality, and enable them to meet the dynamicand static stiffness requirements.The characteristics of the extra-wide coverage remote sensor and difficulties inthe structural design have been analyzed. The structure form of the extra-widecoverage space remote sensor is large ratio of width to length, which is close to1.5:1 Therefore, it is difficult to meet the requirements of the optical imaging quality, if wetake the traditional structure and design means. Because of the stringent requirementof the whole weight, the design margin is extremely small. It requires the structuremore compact and higher accuracy in design, then the difficulty of the structuraldesign is increased.The purpose of this thesis is to design the bottom support structure of theremote sensor. It contains: analysis on kinematic bottom support program, influenceon the pointing accuracy of remote sensor by support structure, analysis on theimaging quality of remote sensor ensured by support structure, dynamiccharacteristics analysis on support structure, the statics and dynamics test forextra-wide field space remote sensor.Firstly, the bottom support structure has been designed. The advantages,disadvantages and applications of rigid support, flexible support and kinematicsupport commonly used in space remote sensors at present are compared, and withthe structure characteristics of the extra-wide space remote sensor, the kinematicsupport has been chosen. Different kinematic support schemes are analyzed in detail.Ultimately, the bottom support is determined to choose the2-RRR+2-RRRR parallelmechanism.Secondly, the installation positions of the bottom support structure have beendetermined, and the influence on the remote sensor’s optical pointing accuracy hasbeen analyzed by means of equivalent mechanism, error analysis of the parallelmechanism and so on. The pointing accuracy has been calculated. The max anglesaround the X,Y,Z are2.6s、2.1s and2.3s, which meets the pointing accuracyrequirements.Thirdly, the contact theory is introduced. Platform adaptability of the bottomsupport structure consists of rotational and motion pairs has been analyzed bynonlinear finite element. And the flatness requirements of satellite platform are putforward. At the same time, the thermal adaptation has been analyzed, and the resultsindicate that the bottom support structure has a good thermal adaptation. So that the remote sensor can keep a good optical imaging quality at the20℃difference intemperature between the remote sensor and environment.After that, dynamic characteristics of the bottom support structure have beenanalyzed, by calculating the model of the kinematic support with gaps. The rotatingpair gaps can be neglected in modal analysis because they have little effect on themodal of the structure. Analysis and calculation of the dynamic characteristics of thebottom support structure have been carried on by means of MPC. The results areconsistent with the component-level mechanical test, and the design requirementshave been met.Finally, the statics and dynamics test for extra-wide field space remote sensorhave been carried out. The statics test includes platform flatness adaptability test,temperature bias test. A good optical imaging quality of the remote sensorthroughout the statics and dynamics test illustrates a point that the design of bottomsupport structure is very successful.更多还原