| Southern paddy field mechanization is an important part of agricultural mechanization in our country,our country paddy field area is only about 30% of total arable land in the national,the rice yield,however,close to half of the total grain output,add rice 50% above the average yield per unit area of wheat,barley,so rice is main food crops in China,the function and significance of the southern paddy rice production mechanization is very obvious.Based on the analysis of the physical and mechanical properties of rice soil,the configuration and parameters of high flower-wheel tires and the parameters of vehicle motion state,a basic ground mechanical model of the interaction between wheel and ground was established.The test prototype and wheel are introduced.According to the required parameters and influencing factors in the model,combined with the operation requirements of the high ground clearance chassis,the wheel-ground interaction test was designed.Using the high ground clearance chassis as a test platform,the wheel slippage,steering,up-down slope,cross-slope and slippage rate tests were carried out.Taking the high ground clearance chassis as the test platform,through the traction performance test,the subsidence characteristics of paddy field high ground clearance chassis wheels are studied and discussed.Under the condition of heavy load of 800～1100kg,the wheel load and slip rate were taken as test variables,and the wheel subsidence coefficient,drive coefficient and hook traction coefficient were taken as test indexes to establish the hook traction performance and subsidence model.The modified parameters of the model are obtained by using the field test,so that the error between the fitted value and the measured value in the field test is less than 5%.Thus,an on-line subsidence prediction model for chassis with high clearance is established.This model can be used for early warning and judgment of excessive subsidence state,and can also provide data of subsidence state for relief after subsidence.The wheel-ground interaction model of rugged paddy field with high ground dynamic chassis is established.This paper introduces the sideway forward model,two-wheel steering model and four-wheel steering model of the wheel in detail,and analyzes the force of the wheel.Field tests were carried out.According to the obtained test data,the influence of design parameters such as wheel width and radius on vehicle performance was analyzed.Combined with the design requirements of high ground clearance chassis,the vehicle performance was analyzed by wheel load effect,which can provide reference for the design of high ground clearance chassis. |
