基于质子交换膜的气动软体驱动器的自密封结构

A Self-sealing Structure for Soft Pneumatic Actuators Based on Proton Exchange Membrane

对于现有的基于质子交换膜的气动软体驱动器,其密封结构是通过软体结构与质子交换膜直接粘接形成的,承受的工作压力较低,从而限制了软体驱动器的性能。为提高基于质子交换膜的气动软体驱动器的工作压力,设计一种利用气动软体驱动器的气腔内压实现密封的自密封结构。通过有限元分析法,分析自密封结构的密封特性以及关键结构参数如斜面倾角、密封圈结构顶面宽度及气腔内侧壁厚度对密封性能的影响。结果发现:增大密封圈结构斜面倾角和顶面宽度,以及降低气腔内侧壁厚度,均能提高自密封结构的密封能力;相较于斜面倾角和气腔内侧壁厚度,改变密封圈顶面宽度能够更显著提高自密封结构的密封能力。结合有限元仿真分析的结果,通过实验测试自密封结构的密封性能。结果表明:采用该自密封结构的基于质子交换膜的气动软体驱动器工作压力更高,变形能力和负载能力更强;而且自密封结构通过密封失效能够对软体驱动器的结构起到过压保护作用。

For the existing pneumatic soft actuator based on proton exchange membrane,its sealing structure is formed by bonding the soft structure and the proton exchange membrane,and the working pressure is low,which limits the performance of the pneumatic actuator.A self-sealing structure that achieves sealing with the pneumatic pressure inside the gas chamber of the soft pneumatic actuator was designed for the soft pneumatic actuator based on proton exchange membrane,so as to improve the working pressure of the pneumatic soft actuator.The sealing characteristics of the self-sealing structure and the influence of the key structure dimensions on the sealing performance were analyzed with the finite element analysis method.It is found that the sealing ability of the self-sealing structure can be improved by increasing the inclined angle and the top width of the sealing ring structure and reducing the thickness of gas chamber inner wall.Compared with the inclined angle and the thickness of gas chamber inner wall,changing the top width of the sealing ring can significantly improve the sealing ability of the self-sealing structure.The sealing performance of the self-sealing structure was tested through experiments with the results of finite element analysis.The experiments show that the soft pneumatic actuator based on proton exchange membrane with this self-sealing structure has higher working pressure and has stronger deformation ability and load capacity.Moreover,the self-sealing structure can protect the structure of the soft pneumatic actuator from overpressure through sealing failure.