基於情境模擬之多軸運動平台控制器設計

Abstract

本論文提出以馬達做為制動器、配合螺桿做省力裝置、擁有三個自由度的運動平台。使用傳統沖洗濾波器(classical washout filter)將加速度轉成平台的姿態角，模擬真實行車狀況中可能會發生的情境；再推導出平台的逆向運動學(inverse kinematics)，使得沖洗濾波器的輸出-平台姿態角能夠轉成三軸運動平台的各軸命令，由此對平台進行控制。

當三軸位置命令送至動態特性不同的馬達上時，由於重力在斜面上所產生的動感受各軸的追跡誤差影響較大，因此本文藉由設計相位領先控制器(lead controller)、零相位誤差追跡控制器(ZPETC)做為各軸控制器，提供系統良好的響應，降低各軸的追跡誤差，達成更精準的重力分量。

另一方面，在六軸運動平台上的輪廓誤差(contouring error)會使得平台跑出的軌跡偏離命令的軌跡，造成乘坐者有錯誤的感受，即錯誤動感(false cue)。本論文整合了單軸控制器設計與交叉耦合控制器(CCC)設計整合，藉著補償器所產生的補償訊號，進一步消除各軸的輪廓誤差，提供良好的六軸動感響應。

In this thesis, a 3 degree-of-freedom (DOF) motion platform with extensible screw bars actuated by servo motors is designed for the motion-cueing simulator with low cost and easy maintenance. Moreover, the classical washout filter can be adopted for generating equivalent acceleration by varying the posture of motion platform. Then, the inverse kinematics is processed for converting the posture of motion platform to the reference signals for three servo motors of the motion platform. The accurate components of gravity on the tilt-surface of 3-DOF motion platform generate desirable motion cueing and its precision has been significantly improved by applying the lead controller and the zero phase error tracking controller (ZPETC), separately, on each axis. Furthermore, to extend motion-cueing control to a 6-DOF platform, the contouring error results in the deviation from the desirable path of the motion platform and the false cue thus occurs. The contouring error was effectively reduced by introducing the cross-coupled controller (CCC) with the lead type controller to obtain the improved contouring accuracy. The integrated control structure with both the tracking and contouring accuracy has been proved to be suitably realized on the 6-DOF motion platform for future development.