Thermal-mechanical Coupling Actuation And Motion Control Of Soft Cavity

As an actuating mode of soft robot,thermal-mechanical coupling produces considerable macroscopic actuation at relatively lower driving voltage or current,and its driving force and mobility are stronger.Based on the research of soft biological kinematics,this paper puts forward a soft cavity with linear motion,and studies the design,fabrication,driving and control strategy of the soft cavity.Firstly,the soft cavity is designed by analyzing the principle of linear motion of soft snake.The soft cavity adopts thermal-mechanical coupling actuation mode,which can realize linear motion,in addition,the soft cavity can adjust the motion strategy in time when encountering obstacles.The mold design adopts the method of recombination of partial casting molds.The mold of cavity and bottom are designed respectively and printed by 3D printing technology,then the soft cavity is made according to the scheme.Secondly,the cavity material of the soft cavity is modified by doping with anhydrous ethanol,in order to induce the soft cavity to produce greater deformation at lower driving voltage or current.The surface morphology and mechanical properties of the modified silica gel/anhydrous ethanol composites were studied in order to determine the optimal ratio of composite materials.The deformation behavior of the soft cavity is explored.At the same time,ABAQUS is used to analyze and reveal the influence of the number of cavity partitions,wall thickness,partition width and partition depth on the deformation of the soft cavity.Finally,the thermal-mechanical coupling of the soft cavity is analyzed to determine the feasibility of the thermal-mechanical coupling actuation mode.The actuating principle of the soft cavity is studied,and according to the structure and moving condition of the soft cavity,the moving process of the soft cavity under the condition of periodic charge and discharge is analyzed.The movement experiment platform was built to test the linear motion and climbing ability of the soft cavity.The results of the experiments show that the designed soft cavity can move forward,stop,delay forward and delay stop,which provides practical experience and theoretical basis for the further development of various soft robots.