Research On Chassis Driving Performance Of Mountain Crawler Self-propelled Pepper Harvester

Guizhou’s landform is a plateau and mountainous area.The cultivated land is soft,the field area is small,and the slope is large.The existing pepper harvesters are difficult to drive on the mountain,which makes it impossible to achieve mechanized harvesting of Guizhou peppers.This paper takes the chassis of the mountain crawler self-propelled pepper harvester as the object,and studies the driving performance of the chassis under typical mountain road conditions.The research work of the thesis is as follows:（1）According to the requirements,characteristics and conditions of the pepper harvester chassis driving in the mountains,the resistance and the interaction force between the track wheels during the driving process of the chassis are analyzed.According to the transmission requirements of the chassis power system,the traction force range required for the chassis driving is estimated,the chassis hydraulic control system is designed,the single pump-dual motor closed drive mode is adopted,and the models of the engine,hydraulic pump and hydraulic motor are determined.（2）Combined with the characteristics of mountain soil and geomorphology,the driving limit state of the typical road conditions in the chassis mountain is analyzed.According to the force of the chassis in the critical state of driving under various typical road conditions,the driving limit slope angle of the chassis transverse slope is calculated to be22°,the limit slope angle of the vertical slope uphill is 28°,and the limit slope angle of the vertical slope downhill is 21.5°.The limit height of crossing the vertical wall is 530 mm,and the limit width of crossing the trench is 1059 mm.（3）Based on the co-simulation technology,the simulation model and co-simulation interface are established through Recur Dyn and AMESim,and the simulation analysis is carried out for the driving state of the chassis under typical road conditions.Using Recur Dyn to carry out dynamic simulation of the driving process of the chassis in typical mountain conditions,the results show that the lateral offset of the chassis is 3.1% in straight-line driving,the turning radius of in-situ steering is1500 mm,the limit slope angle for horizontal slope driving is 22°,and the limit slope for vertical slope uphill driving The angle is 30°,the driving limit angle of the longitudinal slope downhill is 21°,the driving limit height over the vertical wall is 510 mm,and the driving limit width across the trench is 1020 mm.Using AMESim to simulate the chassis hydraulic control system,the results show that the hydraulic motor speed and torque fluctuate slightly at the beginning of the chassis,and then converge to a fixed value,indicating that the chassis hydraulic control system has strong working stability and high reliability,and meets the requirements of the harvester chassis for mountainous areas.Driving power transfer requirements.（4）On the chassis of the physical prototype,field tests were carried out on vertical slopes,climbing over vertical walls and crossing trenches.The results show that the maximum slope angle of chassis climbing is 27°,the relative error with the theoretical value of 28° is 3.57%,and the relative error with the simulation value of 30° is 10%;the limit height when climbing over the vertical wall is 500 mm,and the relative error with the theoretical value is 530 mm.It is 5.66%,and the relative error with the simulation value of 510 mm is 1.96%;the limit width when crossing the trench is 980 mm,the relative error with the theoretical value of 1059 mm is 7.46%,and the relative error with the simulation value of1020 mm is 3.92%.The prototype field test is basically consistent with the theoretical calculation and simulation analysis results,which verifies the accuracy of the harvester chassis calculation and co-simulation model,indicating that the chassis has strong driving stability and passability.