Research On Steering Resistance Of Tracked Vehicle On Soft Ground Based On DEM-MBD Simulation

Tracked vehicles are widely used because of their excellent passability and mobility.Whether tracked vehicles have good steering performance is one of the key factors to evaluate the mobility of tracked mobile equipment.In general,tracked vehicles work on soft ground,so when tracked vehicles are turning,the ground can not provide traction or driving resistance to the vehicles continuously and stably,resulting in vehicle slip and other phenomena in the process of turning,but the existing testing technology is difficult to analyze and study the steering resistance and its characteristics of tracked vehicles.Therefore,based on the background of "analysis of ground resistance of track turning driving",this paper studied the problem of turning resistance in the course of track ground interaction,discussed the law and trend of the change of soil resistance in the process of turning of track vehicles,analyzed the changing of force field and velocity field under the action of track,and improved the theory of track ground interaction.In this paper,a track-ground interaction space system based on DEM-MBD(discrete element and multi-body dynamics)was established.The system includes a dynamics model of complete track vehicle,which has been coupled with discrete element particle bed,and then the track-ground interaction space system was improved.Through the analysis of the system,the influence of the track on the resistance under different driving conditions,such as different running speed,turning radius and vehicle load,and the law of the change of the speed field and force field of the soil under the action of the track are obtained.First of all,the different types of track shoes are tested by the soil groove test and the discrete element simulation analysis,and verified by the soil groove test.The results show that the effect of the height,the angle and the distance of the Spurs on the adhesion decreases in turn,and the adhesion only increases with the increase of the height of the Spurs,which is opposite to the distance and the angle of the Spurs.By comparing the two experimental results,the reliability and scientificity of the discrete element simulation tool are proved.The rolling friction resistance,shear resistance and scraping resistance of the crawler were defined,and the calculation methods of the various resistances encountered during the running of the crawler have been given.Coupled simulation analysis of track steering resistance was conducted based on EDEM and Recur Dyn software,and the influence of track conditions of track vehicles at different steering speeds,steering radii and vehicle loads on the above three resistances and soil were discussed The test results show that the changing of vehicle speed has little effect on friction resistance;On the contrary,the influence of load changing and friction resistance is very significant.when the vehicle does not turn in place,as the turning radius increases,the influence of it on scraping resistance and soil velocity has gradually decrease.When the turning radius of the vehicle decreases,the scraping resistance increases significantly;the changes in the three conditions all have a significant effect on the track shear resistance;the changing in vehicle load and driving speed have a significant impact on the soil stress and soil speed.