Design And Dynamic Characterization Of Permanent Magnet Tracked Crawling Robot Outside The Pipe

As an important transportation tool in petroleum,chemical,steel and other industries,industrial pipelines are required to transport high temperature,high pressure and toxic fluid media for a long time,which will cause significant casualties and property damage in case of leakage.Industrial pipelines are located in a complex environment and are difficult to detect manually,so the study of pipeline robots that replace manual work has important academic research value and application prospects.In this paper,a permanent magnet adsorption crawling robot outside the pipe was designed,and its static mechanics,dynamics and barrier crossing process are analyzed and studied.The main research works are as follows:(1)By analyzing the structural characteristics of domestic and foreign out-of-pipe crawling robots,a permanent magnet adsorption crawling robot outside the pipe was designed,and the core components such as overrun structure,magnetic crawler set and auxiliary adsorption device were designed in detail to make the robot have good load capacity,overrun capability and pipe adaptation capability.(2)The magnetic circuit scheme of the magnetic adsorption structure was designed,and the adsorption force that it can provide during axial and circumferential motions was obtained using Ansoft Maxwell.Experimental studies on magnetic force measurement were also conducted,and compared with finite element analysis and theoretical analysis to verify the rationality of the magnetic adsorption structure design.(3)The mechanical model of the robot was established to obtain the adsorption force conditions for the stable motion of the robot and the relationship between the traction and the variation of position angle,so as to selected a suitable magnetic circuit scheme;on this basis,the robot overrunning process was studied,and the theoretical height range of the robot that can pass the obstacle and the variation of the driving torque required for the overrunning process were obtained,which provided the theoretical basis for the subsequent robot prototype production.(4)Based on the virtual prototype technology,the simulation model was established to analyze two kinds of motion processes,namely,crawling over obstacles and flipping over obstacles,to verify the performance of the robot over obstacles,and to further build a physical prototype of the robot for experimental verification.