Folded, Articulated Manipulator with Inflatable Skin Enabling Bending and Extension Using a Tension Cutoff Mechanism

Robots providing safe services in the same space as humans are popular owing to the aging population. Inflatable structures are suitable for robots that assume physical contact with humans because they enable changes in rigidity according to internal pressurization. However, systems that provide support to relatively heavy objects, such as humans, warrant safety concerns. We introduce a wire bending system with a tension cutoff mechanism that can simultaneously bend and extend with minimal driving force. The system can be installed on an articulated skeleton used to design an inflatable arm. Our research team developed an inflatable arm with both soft and rigid mechanisms by incorporating a folded articulated skeleton into a membrane structure. We verified that the arm could be actively wound around an object without damaging the object using the conventional machine. However, simultaneous bending and extension were not achieved. Therefore, we constructed a wire-bending system in which the driving force of the bending is transmitted only to the necessary point by installing a tension cutoff mechanism in the articulated skeleton. As a result, The simultaneous bending and extension of the inflatable arm were achieved mechanically, and the functionality was successfully improved. This mechanism can be applied to wire-driven articulated manipulators and machines using rotating wires.