Research On Motion Characteristics Of Space Truss Climbing Robot

At present,there are mainly two technical means for on-orbit assembly tasks for space truss structures,including the astronaut's cabin operations and space manipulators.However,the trend of large-scale and complicated spatial structures has given both of them some limitations,for example,risks of extravehicular missions,the limited operating space and poor flexibility of space manipulator.The study of space climbing robot can fully compensate for these deficiencies.In this paper,a climbing robot with biomimetic gecko adhesion structure is proposed and the motion characteristics based on discrete element-multibody system dynamics co-simulation technology is studied.In order to improve robot's adaptability,the overall structure of the robot is determined based on the bionic principle combining the working environment and target materials.The key dimensions of robot are determined by structural design and its virtual prototypes are modeled.The design of robotic adhesion microstructure is completed according to the bionics principle.The scheme of motor function is proposed by decomposing the robot motion,and the kinematics and work space analysis are completed,which can provide the basis for the subsequent simulation parameter setting.Using the discrete element method,the simulation model of robot bionic bristle microstructure is established by particle accumulation in EDEM.Combining kinematic analysis results,aiming at the holding motion of single leg,the kinematics simulation model of robot is established.In zero-gravity environment,the effect of adhesion micro-structures on robotic crawling motion was compared and analyzed through the co-simulation platform,which verify the feasibility of the adhesion climbing scheme.By analyzing the typical six-legged insect's crawling gait,and taking the crawling speed and movement stability into consideration,the triangular gait and the creeping gait are defined in ADAMS.The co-simulations of the overall robot's crawling process are completed separately for the two crawling targets with large-section truss rods and the large-scale truss structures.The variation and influence law of the adhesive force of legs and the related movement characteristics such as body displacement and velocity are obtained,and the gait selection and the target adaptability are analyzed.The machining and assembly of the robot parts were completed based on the robot system design,and the crawling experiment,which aims at the large-section truss rods is conducted using the gravity compensation method to simulate the space low-gravity environment.The motor function of the prototype is tested and the feasibility of the overall scheme with adhesive micro-structure is verified.This will provide reference for further research on the space truss climbing robot.