Position Error Modeling and Compensation for Robot Bonnet Polishing
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摘要: 针对机器人气囊抛光中抛光压力波动的问题,分析影响抛光压力稳定的因素,提出误差补偿法来降低抛光压力波动对加工面形的影响。首先,分析气囊抛光的运动过程,根据Preston方程建立材料去除函数模型,使用MATLAB对去除函数进行仿真分析。然后针对由机器人末端位置波动引入的系统误差,提出网格式误差补偿法,根据误差数据模型对加工点位进行即时修正,从而降低由机器人引入的抛光压力波动误差。实验数据表明:补偿后机器人末端位置X,Y方向误差波动值分别下降了86.2%,67.6%,机器人末端位置精度明显提高,最终加工面形精度的RMS为0.118λ。证明了该方法能够有效的减小抛光压力的波动,改善加工面形质量。Abstract: To remove polishing pressure fluctuation during robot bonnet polishing, the factors affecting the stability of polishing pressure were analyzed. The error compensation method was proposed to reduce the influence of polishing pressure fluctuation on the machining surface. Firstly, according to the motion model of bonnet polishing, the motion process was analyzed, and the material removal function model was established according to the Preston equation. The removal function was simulated and analyzed with the MATLAB. Then, in view of the system error caused by the end position fluctuation of the robot and according to the error data model, the machining point position is corrected immediately so as to reduce the polishing pressure fluctuation error introduced by the robot. The experimental results show that the error values in X and Y directions of the end position of the robot after compensation decrease by 86.2 % and 67.6 % respectively. The accuracy of the robot′s end position is significantly improved, and the RMS of final machining surface accuracy is 0.118λ. It is proved that the error compensation method can effectively reduce the fluctuation of polishing pressure and improve the quality of the machining surface.
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Key words:
- industrial robot /
- bonnet polishing /
- removal function /
- error compensation /
- polishing force
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表 1 气囊抛光实验参数表
参数 数值 磨头转速/(r·min−1) 300 充气压力/MPa 0.1 进动角/(°) 15 抛光压力/N 10 抛光液种类 氧化铈 抛光液浓度/% 10 栅格间距h/mm 0.5 -
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