Research On Multidirectional Crawling Robot Based Two-Dimensional Material

With the rapid innovation of science and technology,robots have entered human life as intelligent devices.In order to adapt to the application of various complex environments,micro crawling robots have been developed vigorously.Among them,the light-responsive crawling robot has fast response,high sensitivity and good driving performance,which has attracted the attention of many researchers.The hot direction of crawling robot development lies in advanced materials,and the two-dimensional materials represented by graphene and its derivatives have become the preferred materials for photothermal crawling robots because of their excellent flexibility and mechanical strength.At present,the crawling control of light-responsive robots by scholars at home and abroad mostly stays in the one-dimensional direction.The proposed solutions for multi-directional movement of crawling robots focus on two forms: asymmetric driving mode and complex material design,and rarely achieve the multi-directional movement of crawling robots through innovative driving structure design.In this paper,the bending mechanical model of typical graphene oxide/polyimide(GO/PI)bilayer membrane structure is analyzed,and the crawling robot based on bilayer membrane structure is designed and manufactured,and its photothermal response and crawling performance under the stimulation of near infrared light(NIR)are explored.After describing the crawling robots with common response types and their applications,the following work is carried out:(1)Based on the theoretical basis of material mechanics and thermodynamics,the bending mechanics model of double-layer film is established,and the motion model of crawling robot is established based on the posture change and crawling law of crawling robot.Finally,the single-cycle motion analysis of two-way drive robot and multi-direction drive robot is carried out,and the robot motion mechanism is obtained.(2)Based on the analysis of inchworm’s motion mechanism,the design of the trunk and foot of the multidirectional crawling robot was completed,and the cross trunk and the multidirectional crawling robot were simulated by COMSOL finite element simulation software,and the structural parameters and functional realization of the robot were determined.(3)The technology of the proposed crawling robot is prepared,and the structure characterization and performance test of the prepared two-way and multi-way crawling robots are carried out,including the photothermal response of the crawling robot and the performance test of crawling in all directions.The test results show that the crawling robot has good photothermal response performance.Under the stimulation of near infrared light,the two-way crawling robot can achieve stable crawling.Experiments on paper,sandpaper and glass with different friction coefficients verify the good environmental adaptability of the two-way crawling robot.In the atmospheric environment(humidity is 40%),the multi-directional crawling robot is stimulated by near infrared light,and the speed in each direction can reach 2.3 mm/min,1.8 mm/min,1.9mm/min and 2.8 mm/min,respectively.The robot can achieve stable multi-directional crawling.By increasing the environmental humidity and the switching frequency of near infrared light when the robot recovers,the moving speed of the crawling robot can be effectively improved.In this paper,two-dimensional material is used as the preparation material of crawling robot,and innovative structure of multi-directional crawling robot is put forward,and the trunk and foot of robot are designed in a novel way,so that the multi-directional crawling movement of robot under the stimulation of near infrared light with the same light source intensity can reach different critical states by time sharing,which greatly reduces the complexity of robot driving mode and structure,and enhances the application value of micro-robot.