Design of three-dimensional binary manipulators for pick-and-place task avoiding obstacles

In this study, we propose a novel design method for a class of three-dimensional binary manipulators, which are considered as a controlled object with the control objective of bringing the end effector of the binary manipulator close to a given target point. The binary manipulator is known for its high reliability owing to its hyper-redundancy, however, its reachable points form a discrete set, dependent on the expansion/contraction length of each binary actuator. In this study, the task for the manipulator is pick-and-place. We define the picking and placing areas, and the path areas that connects them, assuming that there are obstacles around the path. The task requires positioning accuracy in the picking and placing area, while obstacle avoidance is required in the path area. In this study, we propose a design method to satisfy these two different requirements simultaneously. Numerical design results for a three-dimensional truss binary manipulator are presented to demonstrate the effectiveness of the proposed method.