一种含铰接动平台姿态类并联机器人的运动学标定

Kinematic Calibration of a Posture Adjustment Parallel Robot With Articulated Traveling Plate

面向航空制造业大型零部件精确装配的重大需求,研究一种含铰接动平台姿态类并联机器人(4-PRS&H(R))的精度提升问题.首先,基于零件-部件-整机的装配思路,从零件加工设计与部件装配工艺来保证物理样件具有一定的基础精度,并借助区间理论,预估几何误差源对物理样机末端姿态精度的影响程度,其次,在精度预估的基础上,简化基于激光跟踪仪的误差参数辨识模型,然后结合物理样机实际装配精度和其结构的特殊性对测点进行规划,随后针对4-PRS&H(R)并联机器人开展运动学标定实验,激光跟踪仪检测结果表明,该机器人在运动学标定后沿α、β和γ三个转动方向的最大姿态偏差分别由0.195°、0.520°和2.089°降低至0.026°、0.044°和0.519°,且姿态偏差整体波动平稳,以此验证所述运动学标定方法的正确性和有效性.

To meet the increasing requirements for the precise assembly of the large component in aviation manufacturing industry,this paper into an accuracy improvement issue of a one-translational and three-rotational parallel mechanism with articulated traveling plate featuring the 4-PRS&H(R)topology.Firstly,based on the part-component-mechanism assembly idea,the physical prototype is guaranteed to have a certain basic accuracy via the part’s fabrication design and component’s assembly technology.Moreover,the interval theory is used to predict the influence of the geometric error source on the terminal attitude accuracy of the physical prototype.Secondly,with the help of accuracy prediction,the parameter identification model based on the laser tracker is simplified,and then the measurement points are planned according to the actual assembly accuracy of the physical prototype and the particularity of its structure.Finally,the kinematic calibration experiments are carried out aiming at the 4-PRS&H(R)physical prototype.The experiment result shows that three angular max deviation decrease from 0.195°,0.520°and2.089°to 0.026°,0.044°and 0.519°within the prescribed workspace respectively and the overall deviation is more stable.The correctness and validity of the kinematic calibration method are verified.