An Investigation on the Motion Error of Machine Tools’ Hexapod Table

Accuracy is greatly affected by the nonlinear motion of hexapods. This need is more apparent when these mechanisms are employed in machining industry where precision and surface qualities are of critical importance. In this paper, a comprehensive algorithm for tool path programming of the hexapod table is developed. This algorithm is developed based on a circular motion in C#.Net and has the capability of investigating nonlinear motion error to keep it in a controlled range as well. Improved Tustin algorithm is used for interpolating circular path. The effects of different parameters on the nonlinear error of machine tools’ hexapod table during circular interpolation are also investigated in this study. In the circular motion, the optimal radius which provides access to maximum feed rate with least error is obtained by solving Tustin and nonlinear error equations. The results obtained by the theoretical method are further verified through image processing experimental tests. It is found that the results of theoretical analysis and experimental test are in good consistency.

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