Geometrical Parameters Investigation of a Zig-Zag Soft Pneumatic Actuators

Abstract

Unlike conventional rigid robots, soft robots utilize soft materials that allow them to deform based on their structure, enabling safe interaction with humans. Among various pneumatic actuators in soft robotics, pneumatic network (PneuNet) actuators, which consist of bellows-like chambers, enable bending and repetitive actions with minimal material deformation at low pressures. Given that the performance of PneuNet actuators is affected by their geometric parameters, considering the impact of geometric variations is crucial in this field. Herein, the effect of geometrical parameters on a zig-zag soft pneumatic actuator, and an improved version of conventional PneuNet actuators designed for enhanced performance are investigated. Finite element analysis (FEA) indicates that smaller gaps between chambers, thinner bottom layers, and taller chamber heights result in greater bending under the same pressure within the tested parameter range. Experimental results reveal a 30.9% larger bending angle than that of conventional actuators with the same parameters. The FEA results are consistent with the experimental data, exhibiting an error of 10.2%. Furthermore, the tip and grip forces are 1.45 times and 1.3 times larger, respectively, compared to conventional actuators. These results provide direction for the design of zig-zag soft pneumatic actuators, showcasing improved performance over conventional soft actuators. © 2024 Wiley-VCH GmbH.