平面三自由度冗余并联机床的分步自标定方法  

Step-by-step self-calibration of a 3-DOF planar parallel kinematic machine tool with actuation redundancy

作　　者：常鹏[1] 李铁民[1] 刘辛军[1] 

机构地区：[1]清华大学精密仪器与机械学系,北京100084

出　　处：《清华大学学报（自然科学版）》2008年第5期808-811,共4页Journal of Tsinghua University(Science and Technology)

基　　金：国家"九七三"重点基础研究项目(2006CB705400);国家自然科学基金资助项目(50775118;50605041);国家科技支撑计划资助项目(2006BAF01B09)

摘　　要：针对平面三自由度冗余驱动并联机床,提出基于最少参数线性组合理论的分步自标定方法。根据误差模型输出和机构自由度,给出工程中所有常用的测量方式;然后逐一进行辨识性分析,得到各测量方式下可辨识的不同最少参数线性组合;在兼顾辨识完整性和参数辨识性能的条件下,确定出包含分步测量、分步参数辨识、分步误差补偿的分步自标定方法。仿真结果表明:该方法可完全屏蔽掉不影响终端精度的无关参数,并可提高每步中参数辨识的准确性。最终参数辨识结果与设定值基本相同,验证了该方法的可行性。Minimal linear combinations （MLCs） of the error parameters were used to develop a step-by-step self-calibration method for a 3-DOF planar parallel kinematic machine tool with actuation redundancy. All the engineering measurements were given based on error model outputs and mechanism degrees of freedom, with the parameter identification analyses of each measurement then providing a different set of MLCs. The method takes into account the identification integrity and observability, including step-by-step measurement, parameter identification, and error compensation. Simulations show that this robust, effective method eliminates parameters not affecting the final precision and increases the parameter identification accuracies in each step, with estimated errors matching well with their specified values.

关 键 词：并联机床 自标定 参数辨识 

分 类 号：TH115[机械工程—机械设计及理论]