A Novel Varying Angle Fiber-Reinforced Elastomer as a Soft Pneumatic Bending Actuator

Abstract

Soft actuators are inherently compliant, highly dexterous and an extremely lightweight alternative that are progressively replacing traditional electromechanical actuators in a wide range of robotic applications that involves close interaction with humans. This research aims to demonstrate the bending characteristics, and the force response achieved by a soft pneumatic actuator made from a unique fabrication technique; namely continuous fiber reinforcement technique (CFR) to create a fiber braiding, which is significantly simpler than the previous work, which we named as split fiber reinforce technique (SFR). The performances of SFR and CFR were compared. The active layer was a highly elastic material that can stretch up to 900% of its original length without losing its elasticity. Thus, the actuators' angular profiles were improved by a factor of 89% & 92% for the SFR and CFR respectively than that of the benchmark. The CFR actuator in particular was demonstrated to be capable of exerting blocking force of up to 1.63 N at just 30.75% of the input pressure compared to the benchmark actuator, while the SFR was capable of exerting a slightly lower 1.5 N of force beyond which pressurization gave way to lateral expansion. The bending capability and compliance of these varying angle fiber reinforced elastomer-based soft pneumatic actuators shows high potential for implementation in human-centric body powered robotic actuation tasks for rehabilitation and other delicate industrial grasping tasks.