Research On Kinematics Of The Steering Mechanisms Of Crossing Variable Wheel Track Vehicles

The common vehicle track structure is generally fixed,and for agricultural vehicles,adjustable wheel track stepless will expand the scope of the job object,greatly improve the utilization efficiency.For now,the domestic adjustable wheel track vehicles are generally adjusted by artificial level,there is few research field of stepless adjustable wheel track;and many foreign agricultural vehicles have been applied the technique of variable wheel track,such as self-propelled spraying machine,these vehicles are generally have a high degree of automation and expensive,and the use and maintenance is more complex,therefore,the application is greatly restricted in the domestic.By the revelent research on variable wheel track technology,the research group proposed a method of “using cross-axle to change wheel track”,putting the traditional parallel axle changed to cross layout,by changing the angles of axle to indirect realize the adjustable wheel track stepless.Due to the steering performance of vehicle is an important criterion of evaluating work quality,so it's very necessary and valuable to Kinematics research of steering mechanism.First of all,research on steering principle of crossing variable wheel track chassis.According to the characteristics of the crossing variable wheel track chassis continuously variable,putting the traditional fixed parameters steering mechanism changed to “steering unit” of variable parameters,so that the steering characteristics can changing with the change of the wheel track,to ensure normal steering of the vehicle.Optimal design of steering unit,Applied related mechanism theory,establishing plane geometry model for steering unit,according to the steering principle of Ackerman to derive the internal and external rotation angle relationship of crossing variable wheel track vehicle;by using plane geometry model to solve the actual relations of internal and external rotation angle.Establishing multi-parameters optimization objective function of steering unit,determined the relevant constraint conditions,using Matlab to optimal design of the steering unit.Secondly,intensity and stability checking for the steering tie rod.Steering tie rod is a key component to determine whether the steering unit can work normally,finite element analysis of steering tie rod in Ansys,to observe the stress distribution and deformation,to ensure that can meet the requirements of strength and stability.Finally,combined with the design parameters of the vehicle structure,virtual prototype model is established in Adams,Kinematics analysis of steering characteristic on crossing variable wheel track vehicle.The actual change curve of the inner and outer wheel is obtained through the motion simulation,and then compared with the ideal angle change curve of Ackerman,to verify the accuracy of the modeling,simulation and optimal design results.