本文旨在以FPGA實現具有影像回授機械臂操控球桿滾球結合機構之平衡控制，整個系統分為三個部分；第一個部分為影像處理模組，利用影像感測器擷取即時球與球桿機構之影像，從回授影像中計算滾球位置及球桿角度。第二個部分為控制機械臂各軸馬達位置控制的伺服控制模組；以及第三個部分為球桿及滾球控制模組。上述之三個模組皆在FPGA發展板下以Verilog硬體語言實現。滾球位置及球桿角度由影像處理模組計算，基於影像回授的資訊設計PD控制器操控終端器在X-Z平面的位置以及球桿傾斜角度，機械臂的關節各軸為透過反運動學之伺服控制以平衡滾球至期望的位置。

This paper proposes a visual feedback control of a robotic ball- beam balance control system. The FPGA system herein includes three modules. One is image processing module which applies image sensor to capture real-time ball-and-beam information and calculates ball position and beam angle. The second module is servo position control module for controlling a 5-axes robot manipulator. The third module is the ball-beam balancing control module. The system is implemented on FPGA and programmed by the Verilog hardware description language (HDL). First, ball position and beam angle are calculated by image processing module. Based on these visual feedback data, PD controller is designed to control the position of end-effector in X-Z plane and the inclination angle of beam. Finally, the joints of the robot manipulator are servo-control through the inverse kinematics so as to balance the ball at desired position.

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