Study On The Electrically Actuated Performance And Failure Mechanism Of Ag-IPMC Artificial Muscle

IPMC(Ion-exchange Polymer Metal Composite)is a new type of ionic polymer metal composite electrically actuated intelligent materials that has.the advantages of low energy consumption,fast response speeds,light weight and good flexibility which is usauslly prepared by chemical plating method that is the metal is plated on the base film.The electrode material of IPMC is gold or platinum,whose high cost limited the popularization and application of IPMC.Therefore,the investigation of the preparation of low cost electrode materials tends to be an important research direction in the IPMC field.In this article,the Ag-IPMC was prepared by the reduction method adopting Ag with good conductivity as the metal electrodes on both sides of IPMC artificial muscle.The electric actuators performance and mechanical performance were studied and the performance parameters were used to get artificial muscle drive mathematical model.Then outcome of the simulation and experiment were compared.The failure phenomena of the Ag-IPMC artificial muscle was analyzed and the failure mechanism was studied.Moreover,we optimized the preparation process of Ag-IPMC,and constructed entity model with the improved Ag-IPMC and flexible connection,which can prolong the life of Ag-IPMC.The cantilever beam bending test structure was established and the bending swing performance was tested and analyzed.The electric actuators performances of Ag-IPMC prepared by the traditional method was investigated.The relationship between the force output and the driving voltage amplitude,and the relationship between the driving voltage frequency and the driving voltage waveform together with the relationship between the output displacement and the voltage and the frequency were all tested.The tip output speed,the acceleration speed and the angular displacement characteristics of Ag-IPMC were all studied under different water contents.The mechanical properties of Ag-IPMC artificial muscles were studied.By measuring the elastic modulus and Poisson’s ratio,the two parameters Mooney-Rivilin equation was obtained.With the formula method,the different water contents CIO and C01 of Ag-IPMC were acquired.Then according to the super elastic large deformation equation,we have built the Ag-IPMC mathematical model in a non-electrically actuated condition.For different moisture of Ag-IPMC,the comparison of the results obtained from mechanical simulation and experimental was finished,and then the error rate was obtained.The relationship between strain and dehydration was analyzed.Based on the piezoelectric model,the piezoelectric coefficient of twin lamella was equivalent to IPMC model to calculate its strain,and it clearly showed that the smaller water content caused the slower losing of the water.Finally,the piezoelectric coefficients of Ag-IPMC with different moisture content were measured and the variation law of water content with piezoelectric coefficients was obtained.The failure phenomenon of Ag-IPMC was analyzed and the failure mechanism was studied.We compared the failed Ag-IPMC with the one before its failure and got the difference at a macro level.We also observed the surface of Ag-IPMC at a micro level through scanning electron microscopy.After the analysis of the electric actuator sample surface morphology before and after the experiment,it turned out that Ag-IPMC failed after electrical excitation motion and its surface had obvious changes.The stress concentrated on the movement joints leading to hardening phenomenon.According to the failure phenomenon’s features,the failure mechanism was summarized and categorized.Finally,the failure mechanism was studied.The surface energy spectrum scanning for 3 selected fresh Ag-IPMC sample and 5 failed Ag-IPMC sample was completed.The law of variation of the component before and after failure of the Ag-IPMC sample was analyzed and the effect of the variation of the surface component on the failure was investigated and the reason of failure was uncovered.In order to improve the performance of Ag-IPMC and to avoid the failure in the process of electrically actuated,the preparation method was improved.Through the analysis of the failure phenomena of Ag-IPMC and electrical excitation effect,the whole process of preparation of Ag-IPMC was optimized.Several key factors that can effect the preparation quality of the Ag-IPMC were also studied.The flexible connection with bionic tendon structure was formed by the double piece parallel combination of the improved Ag-IPMC with bonding method and the bionic fish tail was fabricated and studied.The purpose was to solve the the force output size and the failure problem of clamping piece and to improve the performances of the Ag-IPMC in practical application.The main research was focused on the following aspects,that is,the preparation of the fishtail structure model,the preparation of the actuator with the double piece parallel combination of the Ag-IPMC,the preparation of the bionic fish tail and the testing of the fish tail solid model.Through research the solid model and prolonging the service life of the Ag-IPMC,the Ag-IPMC performance has reached a high level,which supplied basis for further research and application of Ag-IPMC.