サーボ系の特性によって生じるパラレルメカニズム特有の多自由度運動誤差の解析とフィードバック制御によるその抑制

概要

論文の詳細を見る
Dynamic motion errors exist due to servo characteristics in parallel kinematic mechanism (PKM) machine tools with 6 degrees of freedom. In this study, at first, analytical investigation is carried out using transfer function of local servo system and Jacobian matrix, in order to clarify the causes of the particular dynamic motion characteristic on errors in PKM machine tools. As the results of the analysis, it is newly founded that the discrepancy between two coordinate transformations, which are used for inverse kinematics calculation and for forward kinematics calculation, causes the particular motion errors. After that, a feedback controller based on the tool tip position and orientation is proposed in order to compensate the particular motion errors. As the results of circular motion simulations, it is clarified that proposed feedback control system, which refers the predicted tool tip position and orientation and consists of Jacobian matrix, can eliminate the particular motion errors of PKM machine tools successfully.