Inflatable Robotic Arm with Overlaid Plastic Sheet Structure

An inflatable structure has been focused by several researchers in the field of soft robotics, owing to its features: flexible, lightweight and compactable. In particular, inflatable robotic arms have been expected to perform daily tasks near humans due to safe contact. To date, several inflatable robotic arms have been proposed, however, the number of robotic arms composed of only plastic materials is quite limited. In addition, the control performance of the robots has not been discussed sufficiently.This paper proposes a novel inflatable robotic arm composed of poly-laminated sheets and low-density polyethylene (LDPE) sheets. The combination of the two materials provides high-pressure resistance. Several advantages are also given: high torque, high control performance, and high load capacity. Moreover, both pressure and visual feedback controls are utilized to realize precise motion control. The end-effector of the robot is composed of pleated structures and grasps flexibly according to object shapes. The performance of the robot is finally described by some experiments.