Study On The Preparation And Performance Of Ethanol Phase Change Soft Artificial Muscle Actuator

Artificial muscle is a kind of flexible intelligent material which can present various complex forms according to the changes of external environment,such as bending,stretching,twisting,contracting,etc.,and its behavior is very close to the real muscle fiber.In recent decades,with the research and development of bionic robot and intelligent actuator,the improvement of artificial muscle performance and the development of new artificial muscle have become more and more urgent.In practical application,in order to better realize the driving function,artificial muscle often needs to have high power density,light weight,small volume,large driving force,safe use way,simple operation method and so on.There are many different systems of artificial muscle materials,among which,as a new system,phase-change artificial muscle can achieve reversible phase change between liquid vapor or solid-liquid through the change of temperature,accompanied by large volume change.Therefore,the phase-change artificial muscle has the outstanding characteristics of large strain,high stress,simple driving,high energy density and fast response rate,which is very close to the biological muscle,and has a very broad application prospect in the field of intelligent robot.With the development of the research on phase-change artificial muscle,the requirement of its driving performance is higher and higher,but the driving speed of the artificial muscle will inevitably lose its driving force.Therefore,how to improve the driving speed and driving force of phase-change artificial muscle is the key problem to be solved.Ethanol phase change artificial muscle based on ethanol solution has very excellent driving performance,which can produce large strain and stress under low voltage.It is safe and convenient to operate,with high power density,but its driving deformation rate is relatively low.Therefore,in order to solve the problem that it is difficult to improve the deformation rate and driving force of the ethanol phase-change artificial muscle at the same time,starting with the structure and material modification of the ethanol phase-change artificial muscle,a series of imitated mckibbe with low-voltage driving,large strain and fast response deformation characteristics were prepared by adding different kinds and different content of heat conducting medium and using the rapid prototyping method N-type ethanol phase-change artificial muscle,which realizes the effective consideration of deformation rate and driving force,provides an effective new idea and method for solving the bottleneck problem of ethanol phase-change artificial muscle.The specific research contents and main conclusions are as follows:(1)The driving mechanism of the ethanol phase-change artificial muscle is that the reversible phase-change of the ethanol stored in the elastic siloxane elastomer under heating conditions and the coordination between the reversible phase-change and the external excellent elastic siloxane elastomer,resulting in the reversible expansion and contraction of the whole body.The ethanol phase-change artificial muscle is mainly divided into three parts: heating resistance wire,siloxane elastomer matrix and ethanol phase-change fluid.Resistance wire,as the power source of electric drive,causes the bubble of ethanol phase-change fluid contained in the siloxane elastomer matrix to produce vaporization expansion and drive the expansion deformation of the siloxane matrix.When the heating is stopped,the vaporized ethanol cools and liquefies,The silicone elastomer with high elasticity returns to its original shape,and the ethanol phase-change artificial muscle can contract.When the woven mesh becomes a woven alcohol phase-change artificial muscle,the former axial expansion can be converted into radial contraction through the constraints of both ends of the woven mesh.When the woven alcohol phase-change artificial muscle is electrified,the ethanol phase-change artificial muscle inside the woven net expands,and the outer woven net constrains the radial expansion of the ethanol phase-change artificial muscle at both ends,which makes it produce axial contraction.After power-off,the elastic ethanol phase-change artificial muscle gradually returns to its original state,the radial diameter of woven ethanol phase-change artificial muscle becomes smaller,the axial length becomes longer,until it returns to the state of no power on.(2)This paper analyzes the structure of the phase-change artificial muscle of ethanol,and through changing the heat conduction medium,the exploratory research on the driving performance enhancement of the phase-change siloxane actuator is carried out.Graphene oxide and gold nanoparticles were added to the siloxane matrix material to prepare graphene oxide/ethanol phase-change siloxane actuator and gold nanoparticles/ethanol phase-change siloxane actuator,respectively.Adding graphene oxide and gold nanoparticles can improve the heating rate of the material,increase the driving rate of ethanol phase-change artificial muscle,increase the deformation contraction rate,and add gold After nano particles and graphene oxide,the maximum stress and fracture strain of siloxane elastomer are increased,but the elastic modulus is decreased,which improves the mechanical properties of siloxane elastomer,which can promote the driving ability of ethanol phase-change artificial muscle.It has been proved that the driving ability of GO/ethanol phase-change artificial muscle actuator can be improved by adding heat conduction medium,and the driving ability of GO/ ethanol phase-change artificial muscle actuator is better than that of gold nanoparticles/ethanol phase-change artificial muscle actuator in all aspects.(3)Based on the research on the driving performance of ethanol phase-change artificial muscle by adding different heat conduction media,it is found that the driving performance of ethanol phase-change artificial muscle can be enhanced by adding graphene oxide,and graphene oxide is selected as the heat conduction medium to improve ethanol phase-change artificial muscle.With the increase of graphene oxide content,the deformation speed of graphene oxide/ethanol phase-change artificial muscle actuator increases.When 15 mg is added,the fastest driving speed is 0.19mm/s The driving speed of phase-change artificial muscle without ethanol increased by 61%,and the driving force increased by 52.7%.The graphene oxide/ethanol siloxane actuator has a faster driving speed and a stronger driving force.The driving force can reach 1.68 n after being electrified for 120 s,and the weight can be lifted by 12 mm in 300 s.