一种新型四自由度姿态调整机构的误差补偿策略研究

发布时间：2018-02-24 00:43

本文关键词： PaQuad并联机构误差建模与验证灵敏度分析精度预估运动学标定　出处：《天津大学》2016年硕士论文　论文类型：学位论文

【摘要】：密切结合国家飞机制造业对部件级精密对接装备的重要需求,在国家自然科学基金青年项目和教育部博士点基金的资助下,本文以一种新型四自由度姿态调整机构Pa Quad为对象,深入研究这类含铰接动平台并联机构的几何误差补偿策略,内容涉及位置逆解与速度映射、误差建模与验证、精度分析与预估以及运动学标定等。取得的研究成果如下:1.位置逆解与速度映射。结合Pa Quad并联机构的特点,利用矢量链法建立该机构的位置逆解模型;基于螺旋理论建立该机构的速度映射模型,获得其全阶速度雅可比矩阵。2.误差建模与验证。利用螺旋理论建立Pa Quad并联机构末端位姿误差与各支链几何误差间的误差映射模型,并借助商用Solid Works软件对误差模型进行仿真验证,为指导装配工艺与物理样机的运动学标定提供数学模型。3.精度分析与预估。基于灵敏度系数法对几何误差源进行精度分析,通过设计装配工艺来消除/抑制灵敏度较大的几何误差,保证物理样机具有一定的基础精度。同时通过测量手段确定几何误差值,并基于区间理论,预估几何误差源对物理样机末端精度的影响程度,为合理简化参数辨识模型提供理论依据。4.运动学标定。在精度预估基础上,建立基于激光跟踪仪的Pa Quad并联机构误差参数辨识模型,借助商用Solid Works软件仿真运动学标定流程,验证其有效性。将上述流程应用于Pa Quad物理样机的运动学标定,使得沿α、β和γ三个转动方向的最大姿态偏差由0.197°、0.522°和2.098°分别降低至0.027°、0.046°和0.521°,由此证明了本文所述误差补偿策略的有效性。本文的研究工作为Pa Quad并联机构在飞机部件级精密对接领域的应用奠定坚实的理论与技术基础。
[Abstract]:In close connection with the important demand of the national aircraft manufacturing industry for the component level precision docking equipment, with the support of the National Natural Science Foundation Youth Project and the doctoral Program Foundation of the Ministry of Education, this paper takes Pa Quad, a new four-degree-of-freedom attitude adjustment mechanism, as an object. The geometric error compensation strategy of this kind of parallel mechanism with hinged platform is deeply studied, which involves the inverse solution of position and velocity mapping, error modeling and verification. The research results are as follows: 1. Position inverse solution and velocity mapping. According to the characteristics of Pa Quad parallel mechanism, the position inverse solution model of the mechanism is established by vector chain method. Based on the helical theory, the velocity mapping model of the mechanism is established, and its full-order velocity Jacobian matrix .2. the error modeling and verification are obtained. The error mapping model between the end position error of Pa Quad parallel mechanism and the geometric errors of each branch chain is established by using the helical theory. With the aid of commercial Solid Works software, the error model is simulated and verified, which provides a mathematical model .3. precision analysis and prediction for guiding the kinematic calibration of assembly process and physical prototype. The accuracy of geometric error source is analyzed based on sensitivity coefficient method. The geometric error with high sensitivity is eliminated / suppressed by designing assembly process, and the physical prototype has certain basic precision. At the same time, the geometric error is determined by means of measurement, and based on interval theory, The influence of geometric error sources on the end accuracy of the physical prototype is estimated, which provides a theoretical basis for reasonably simplifying the parameter identification model .4.Kinematics calibration. The error parameter identification model of Pa Quad parallel mechanism based on laser tracker is established. The validity of the model is verified by using commercial Solid Works software to simulate the kinematics calibration process, which is applied to the kinematics calibration of Pa Quad physical prototype. The maximum attitude deviation along the three rotation directions of 伪, 尾 and 纬 is reduced from 0.197 掳to 0.522 掳and 2.098 掳to 0.027 掳/ 0.046 掳and 0.521 掳respectively, which proves the effectiveness of the error compensation strategy described in this paper. The application of class 3 precision docking field lays a solid theoretical and technical foundation.
【学位授予单位】：天津大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：V262

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