Structural Design And Mechanical Analysis Of Wall-Climbing Robot For The Large Metal Tank

In order to prevent accidents such as leakage or explosion of large metal tanks,it is necessary to carry out regular inspection.Due to the disadvantages of manual detection,such as high cost of inspection,high labor intensity,environmental pollution and so on,it has become a research hotspot to use robot instead of manual detection.In order to solve this problem,a magnetic adsorption wheel climbing robot is designed to carry the detection device for the detection of the large metal tank.The main work of this article are as follows:(1)The two key functions of the wall-climbing robot's adsorption and movement are analyzed,and the wheel type and the permanent magnet adsorption are selected,and the permanent magnet wheel is designed by combining the two functions.Since the wall surface of the metal tank is curved,in order to ensure that the wall-climbing robot can keep four wheels in contact with the wall surface in any posture,a split structure of left and right body is designed,and the two bodies are connected by a rotating connection mechanism.At the same time,in order to meet the requirements of the car body structure,the transmission system of the robot is designed in detail.(2)The posture analysis model of the wall-climbing robot on the wall of the tank is established.In order to avoid dangerous situations such as sliding and overturning,the static mechanical analysis of the wall climbing robot under different movement conditions are carried out,and the conditions that the adsorption force of the robot needs to meet are obtained.Then based on the mechanical analysis,the driving characteristics of the wall-climbing robot are analyzed,mainly for the two situations of robot climbing and steering movement,the maximun driving torque of one side of the robot is obtained,and the types of the motor and the reducer are determined.(3)The magnetic wheel of the robot is designed emphatically.The materials of different parts of the magnetic wheel are determined,and the optimal magnetic circuit scheme is selected by comparing and analyzing different schemes.The 3D module of Ansoft is used to simulate and analyze the magnetic field of the magnetic wheel,and the complete size parameters of the magnetic wheel are determined.Since there is a gap between the magnetic wheel and the wall of the cylindrical tank in the actual situation,the calculation method of the gap between the magnetic wheel and the tank wall is proposed.The contact mode between the robot and the cylindrical tank body is analyzed,the posture of the robot on the tank wall are described by the method of coordinate transformation,and then the change law of the gap between the wheel and the tank wall is solved by the geometric method.The influence of the gap on the adsorption force is obtained by Ansoft,which verifies the design of the magnetic wheel can meet the adsorption requirements.(4)Based on the previous research,the first-generation functional prototype of the wall climbing robot is developed.The test environment is built by simulating the cylindrical tank,the prototype of wall climbing robot is tested for straight-line movement,cross the welding seam and turning,etc.In view of the shortcomings of the first-generation functional prototype,the overall structure was improved,a new functional prototype is obtained,and the motion test is conducted.The test result shows that the new functional prototype can meet the functional requirements.