Development of universal vacuum gripper for wall-climbing robot

Task performed at a height, such as wall inspections are one of the dangerous tasks for humans. Thus, robotic technology for safety inspection is required. This research focuses on developing robots to climb vertical walls with flat and uneven surfaces, e.g. concrete, tile and riveted structure. To have wall-climbing capability, climbing robots use vacuum pads, claws, magnets, intermolecular force, and adhesive. However, each of these approaches has disadvantages. To achieve wall climbing on an uneven surface without scratching and staining, we have developed a novel vacuum pad named the Universal Vacuum Gripper (UVG), which is based on the Universal Gripper (UG). The UG is a robot hand using jamming transition of coffee powder inside a balloon to grip uneven material. The UVG is a vacuum pad with a deformable skirt based on the UG. If the skirt shape is deformed in accordance with the contact surface, air leaks can be avoided. Moreover, the deformed skirt can be stiffened, thereby working as a gripper. Here, we evaluate the proposed gripper, having both grasping and adhesion force. We also develop a wall-climbing robot with UVGs, and evaluate its performance on uneven surfaces under real-world conditions.

高空作业任务（如墙体巡检）是极具危险性的人类作业类型之一，因此安全巡检用机器人技术的研发需求日益凸显。本研究聚焦于开发可在平整及凹凸表面（如混凝土、瓷砖与铆接结构）实现垂直攀爬的机器人。为实现墙体攀爬能力，爬壁机器人通常采用真空吸盘、爪式机构、磁吸装置、分子间作用力以及粘合剂等方案，但各类技术路径均存在各自的缺陷。为实现在不划伤、不污染被检表面的前提下完成凹凸表面墙体攀爬任务，我们基于通用夹具（Universal Gripper, UG）开发了一款新型真空吸盘，命名为通用真空夹具（Universal Vacuum Gripper, UVG）。UG是一种利用气球内咖啡粉的颗粒堵塞相变来夹持凹凸材质的机器人手部装置；UVG则是基于UG开发的、带有可变形裙边的真空吸盘。若裙边形状可随接触面自适应变形，则可有效避免空气泄漏；此外，变形后的裙边可被固化，从而兼具夹具的夹持功能。本研究对这款兼具吸附力与夹持力的新型夹具进行了性能评估，并开发了搭载UVG的爬壁机器人，在真实工况下的凹凸表面完成了机器人整体性能测试。