3-UPS/S并联稳定平台满载工况误差分析与运动学标定

Error Analysis and Kinematics Calibration of 3-UPS/S Parallel Stabilizing Platform in Full Load Conditions

当负载达到一定数值时,并联机构的变形误差相对于几何误差对动平台输出精度的影响是不可忽略的。以电液驱动型3-UPS/S并联稳定平台为研究对象,分别建立了稳定平台几何误差与变形误差的传递模型,并通过线性叠加得到了总的误差传递模型。基于几何误差传递模型,建立了稳定平台满载工况下的运动学标定模型。在满载工况下进行了运动学标定实验,测量了动平台参考点的位置,计算得到动平台姿态误差δH_0,通过分离变形误差δH_1得到了几何误差δH,通过最小二乘法完成了稳定平台几何误差参数标定。

Compared to geometric er rors , output accuracy of moving platform influenced by deformation errors might not be ignored when the loads of any parallel mechanism reached a certain vaues. Geometric and deformation error models were established based on parallel mechanism, whicwere studied for an electro-hydraulic 3-UPS/S stabilized paltform？ and a total error transfer modewas established by linear superposition of geometric and deformation errors. Based on the geometrierror model, a kinematics calibration model of the stabilized platform was established. Kinematics caibration experiments were completed in full load conditions, positions of the reference points on moving platform were measured. Posture errors δH0 of the moving platform were calculated,geometrierrors δH0 were obtained by separating the deformation errors Sif δH0 ,and then the calibrations of geometric error parameters were completed based on least-square method.