Design And Electrical Deformation Research On Dielectric Elastomer Laminated Actuators

The dielectric elastomer actuator is a new type of the flexible actuator.When the electric field is applied,the actuator produces axial deformation due to the thinning of the dielectric elastomer film thickness.It has the characteristics of good deformation effect,fast response,strong environmental adaptability,high fatigue life and good bionic performance.It has a wide range of applications in intelligent wear,bionic medicine,aerospace and other fields.In order to improve the deformation ability of the actuator,the researchers designed different structures of the dielectric elastomer actuator,such as push-pull structure,bowtie structure,diamond structure,helical structure,etc.They are mainly to improve the structure basis on the single-layer actuator,in order to obtain applications in specific fields.The actuators with various structures can deform under the electric field strength,but there are some limitations,such as heavy supporting elements,complex manufacturing process,and difficult to maintain stable pre-stretch.Therefore,in order to improve the electrical deformation of the actuator,a new type of dielectric elastomer laminated actuator is designed and manufactured.Compared with other structural actuators,it is relatively simple in manufacturing method.The deformation in the direction of material thickness is transformed into directional linear displacement,which can obtain good deformation effect and driving ability.So it can be applied to tactile display,peristaltic pump,artificial limb,intelligent hand rehabilitation splint,intelligent wear and other aspects.The main work of this paper is as follows:(1)The fabrication of the single-layer actuator and the research on its electrical deformation performance were carried out.The single-layer actuator is the basic unit of the laminated actuator.Therefore,it is necessary to study and understand the single-layer actuator before designing and studying the laminated actuator.The single-layer actuator was bulit with acrylic VHB4910 and silicon-gel mixture.By changing the electrode areaand the pre-stretch rate of the single-layer actuator,the research on the electrical deformation was prepared for the design and research of later laminated actuators.(2)Based on the single-layer actuator,the design and fabrication of the laminated actuator were carried out,and its electrical deformation performance was studied.The stacked actuator was made in a flat manner.On this basis,the folding actuator was made by simplifying the process.By changing the number of layers,the area of electrode and the pre-stretch rate of the two actuators,the electrical deformation was studied.In order to further optimize the fabrication method and deformation effect,a rolling method is proposed to fabricate the laminated actuator,and the experiment of the number of rolling layers and the pre-stretch rate on the electrical deformation performance was studied.The results show that the performance of the laminated actuator is significantly improved by changing the fabrication method.Among the three kinds of laminated actuators,the rolling actuator has 37.16% maximum axial strain and the most obvious deformation effect.(3)The simulation and the analysis of the electrical deformation performance of the laminated actuator were carried out.By deriving the constitutive relation of the laminated actuator,the mathematical model of electrical deformation using Yeoh strain energy function was established.The relationship between the pre-stretch rate and the voltage as well as the strain was obtained.Based on the mathematical model,ANSYS Maxwell finite element software was used to simulate the electrical deformation.By comparing the simulation results with the measured results,not only the accuracy of the measured data can be verified,but also the electrical deformation performance of the laminated actuator can be further analyzed.The suitable categories of axial strain and electric intensity were obtained,and then the optimization method to improve the electric deformation of the actuator was proposed,in order to provide the research basis for the design and development of the micro actuator.