摘要
为减小球铰间隙误差对并联机构动平台运动精度的影响,以Stewart并联机构为例,借助静力学分析对球铰间隙误差进行了标定和补偿。首先,采用序列法对机床结构误差及球铰间隙误差进行了标定。其次,采用螺旋理论分析了该机构运动支链的受力状态,进而得到支链在分别受拉力和压力时球铰的作用状态,从而推导出了球铰间隙误差的补偿算法,并通过试验方法对该算法进行了验证。结果表明,基于静力学分析对球铰间隙误差进行相应补偿,可以明显提高并联机构动平台的运动精度。本文提出的针对球铰间隙误差的有效补偿算法为并联机构运动误差的实时补偿提供了参考。
In order to reduce the effect of spherical joint space errors on pose accuracy of parallel machine tool, taking Stewart platform for example, spherical joint space errors are calibrated and compensated by means of statics analysis. Firstly, structural errors and spherical joint space errors of Stewart platform are calibrated by serial method. Secondly, the strained condition of every link is analyzed based on screw theory. And then the situation of leg with joints under pulling force or pressure is obtained. The compensation algorithm of spherical joint space errors are obtained and verified by experiment. The results indicate that the compensation for spherical joint space errors based on statics analysis is capable of improving motion accuracy of Stewart platform. A efficient compensation algorithm for spherical joint space errors is proposed and meanwhile a reference for real-time compensation for motion error of parallel machine tool is provided.
出处
《航空制造技术》
2016年第6期104-109,共6页
Aeronautical Manufacturing Technology
关键词
并联机构
球铰间隙误差
静力学分析
误差补偿
Parallel machine tool
Spherical joint space error
Statics analysis
Error compensation
