DEVELOPMENT OF A REEL-OUT MECHANISM WITH LARGE DYNAMIC RANGE TENSION CONTROL CHARACTERISTICS FOR CASTING MANIPULATOR

摘要

Casting Manipulator is a robot manipulator which throws the gripper connected to flexible string. The mid-air position and orientation of its gripper can be controlled by tension of the flexible string. In order to achieve large workspace and precise position and orientation control of gripper, a reel-out mechanism with large dynamic range tension control characteristics was proposed. The mechanism is a modified spinning reel system which controls tension by torque and effective radius of its arm. Arm's torque is controlled by a hysteresis brake, and its effective radius is controlled by the position of a ring driven by a crank-slider mechanism. The relationships among arm's torque, effective radius and tension have been investigated theoretically and experimentally. The results showed that proposed mechanism can control tension within a large dynamic range by means of arm's torque and its effective radius.