| Soft robots have attracted extensive attention in high human-robot interaction scenarios and unstructured environments due to their low density,lightweight,flexible and deformable materials,quiet and emission-free operation,as well as safety,environmental friendliness,and energy efficiency.The actuator components made of smart materials such as dielectric elastomers are the core of achieving motion and intelligent interaction in soft robots,and their performance determines the overall functionality of the robots.However,the comprehensive performance of soft material actuators is directly influenced by material properties and structural design.As the field of soft robot actuators is still emerging,research on their theory,materials,and structural design is not yet mature,requiring further exploration of their potential.This paper primarily focuses on the analysis of large deformation coupling between electrical and mechanical effects by employing theoretical modeling and finite element simulation methods.It explores effective approaches to enhance actuator performance by synthesizing dielectric elastomer thin film materials,electrode materials,and evaluating their various properties.The study investigates the structural parameters and driving effects of various simple structural actuators,aiming to remove obstacles for the development of high driving force,large deformation,and high degree of freedom actuators,laying the foundation for further optimization of structural parameters in soft robots.A theoretical framework for analyzing the coupling between electrical and mechanical effects in large deformations is established,utilizing the free energy density function to represent the incompressible ideal dielectric elastomer model and incorporating various hyperelastic material models represented by principal stretch ratios and strain invariants.Various non-ideal factors are discussed,and their functional representations are summarized.Based on this framework,the paper analyzes the calculation formulas for stress-strain and prestretch states during the electro-induced deformation process under different deformation modes.The safe space for driving deformation is analyzed and calculated under various failure mode restrictions.The performance of materials has a direct impact on the driving performance of dielectric elastomers and actuators.Laboratory-synthesized dielectric elastomer materials based on CN9021 NS polymer as the matrix are tested for their mechanical and dielectric properties.The study explores methods to enhance their performance.The material ratio and fabrication process of composite polymer flexible electrodes based on the sylgard184 material matrix are investigated experimentally,analyzing the effects of components such as single-walled carbon nanotubes,conductive carbon esters,and carbon black,and obtaining layered electrodes with excellent stretching performance.Comparative tests are conducted to evaluate the changes in sheet resistance of various electrodes under tensile deformation,enriching the foundation for subsequent research on manufacturing processes and material performance optimization.The structure of the actuator directly determines its deformation mode,actuation capability,and output force.This paper presents a detailed analysis process for simulating the deformation of dielectric elastomer actuators using the Abaqus software and subroutines based on the finite element method.In a progressive manner,the analysis includes various structures such as planar single-layer antagonistic actuators,layered bending actuators,multi-layer roll actuators,and spring-coiled actuators.The influence of structural dimension parameters on the actuation performance is studied.The effectiveness of testing layering techniques,antagonistic mechanisms,and rigid-flex coupling structures in enhancing the actuator’s deformation capabilities is confirmed,and parameter optimization design is sought. |
