Research On The Motion Characteristics Of Serpentine Robots For Lunar Crater Detection

In the lunar sampling direction of the aerospace industry,it is difficult to collect deep-level lunar soil samples due to the excessive thickness of the lunar soil and the dynamic limitations of the sampling system.The lunar crater's cliff wall has a clear layer of lunar soil,and the drilling depth is significantly reduced,but the common detection device is difficult to adapt to the steep slope environment.This paper proposes an innovative concept of using a snake-shaped robot to detect craters.The snake-shaped robot has low center of gravity,good stability,high flexibility,and strong environmental adaptability,and can efficiently support sampling work.In view of the above problems,this paper designs the system configuration of the snake-shaped robot based on the biological characteristics of the snake,establishes the robot dynamics model under the crater cliff environment,and builds the discrete element technology-multi-body dynamics joint simulation platform to establish the moon soil.The environmental model is optimized for the motion strategy of the snake-shaped robot.The characteristics and moving gait of the biological snake are explored.The system configuration of the snake-shaped robot is designed based on the bionic principle and the lunar soil environment.The multi-module orthogonal connection of the head,joint and tail is designed,and the driving mode is selected reasonably.The ring component increases the tightness in the lunar soil environment.It is reasonable to simplify the three-dimensional structure several times to a dedicated model for simulation analysis.Based on the DH coordinate method,the ground friction model is analyzed,and the ground friction model of the single-section module is established.Based on the pressure subsidence theory,the monthly soil resistance model of the single-block module is established.Finally,the overall force equation of the snake-shaped robot is established.Based on the discrete element theory,a multi-month soil particle model is established by using the concept of fractal dimension,the initial lunar soil environment of the crater is accumulated,and the crater environment is simulated.The kinematic model of the snake-shaped robot is established based on the serpenoid curve to control the motion equation of the robot in ADAMS.The EDEM-ADAMS coupled simulation platform is used to simulate the snake-shaped robot under the crater cliff,and the parameters such as resistance change,motion speed and displacement of the robot modules are obtained.According to the optimization analysis of the motion parameters and environmental parameters of the snake-shaped robot,the parameters of the slanting angle of the crater,the angle between the crawling direction of the robot and the tilting direction,and the amplitude of the motion of the robot are included in the reference.The most value method and the mean method are used to analyze the change and influence law,and the snake-shaped robot prototype is used to verify the motion strategy optimization of the crater cliff-shaped snake-shaped robot.This work is useful for the lunar exploration sampling and analysis of the reliability and safety of the robot.