A Compliant Hinge Joint Driven by the PneuNets Bending Actuator

Abstract

Abstract While soft robots enjoy the benefits of high adaptability and safety, their inherent flexibility makes them suffer from low load-carrying capacity and motion precision, which limits their applications to a broader range of fields. To address this problem, we propose a novel compliant hinge joint with a stiff backbone for load-carrying coupled with soft pneumatic networks (PneuNets) bending actuators. We derive a pseudo-rigid-body model of the joint design and validate it through experiments and simulations. The results show that the joint can achieve a large range of bending angles. The off-axis stiffness is from 16.74 to 627.63 times the in-axis stiffness. This design can carry a heavy load off-axis while maintaining the in-axis flexibility. This work lays out the foundation for designing high-performance soft robots by combining various flexure mechanisms and pneumatic bending actuators.