Application of 3D Printed Vacuum-Actuated Module with Multi-soft Material to Support Handwork Rehabilitation

Soft modular robotics is a research field that pursues body flexibility while maintaining reconfigurability by employing flowable or soft materials as the main constituent materials of modular robots. In soft modular robotics, a hollow structure made of silicone is created, and the inside of the structure is pressurized to generate stretching and bending motions as an actuator module. In general, it is important to design modular robots with reconfigurability, various deformability, and environmental adaptability. Modularization of soft actuators with reconfigurable and diverse deformability allows morphology to be tailored to the desired task. We have developed a soft actuator module, MORI-A, that combines hollow silicone and 3D printable deformable structures (uniaxial shrinking, bending, shearing, uniform contracting, and no deformation). This study proposes a functional extension of the module “MORI-A FleX” for application as a wearable device for physical rehabilitation using this MORI-A module. Our MORI-A FleX connector is a thermoplastic polyurethane flexible connector that can be coated with materials that offer different textures to achieve excellent connectivity and texture variation. We have assembled MORI-A Flex as a rehabilitation device for hand work, assisting the fingers to move harmoniously and enabling them to grasp a slippery, brittle half-boiled egg and a PET bottle containing 200 ml of water in a deactivated state.