Research On Driving Stability For Semi-trailer Tractor Based On ADAMS

With the raise of the vehicle manufacturing level and the improvement of the roadconditions，in particular the development of highways, now heavy-duty semi-trailertractor is moving in the direction of the high-speed，efficient and convenient，andoccupies an important position in the transport industry. Heavy-duty semi-trailer tractorimproves the transport efficiency while also increases the incidence of traffic accidents，and the consequences are often much more serious than ordinary light-duty cargovehicles. Due to the characteristics of the high center of mass location，large mass andvolume，a narrow wheelbase relative to body height，amplifying rear motion and alsothe complex coupled relationship between the tractor and the semitrailer，heavy-dutysemi-trailer tractor is prone to dangerous working conditions during driving, such asextreme vibration，side and fold. Therefore, the study of driving stability of theheaver-duty semi-trailer tractor has important significance.Automobile driving stability refers to the ability to remain the normal state anddirection，and not to lose control while appears the phenomena of sliding andoverturning，under the action of external factors. The main influencing factors are itsmain structural parameters，the driver，s operation technology as well as external factorssuch as roads and the environment. This article sets up a dynamics model of aheavy-duty semi-trailer tractor based on ADAMS/Car. Its front suspension uses less leafspring，rear suspension uses composite suspension with leaf spring and the air spring，cab suspension uses four-point suspension all air bag spring suspension，and semi-traileruses three-axis air spring suspension. In order to ensure the correctness of the model，this article sets up，verifies and adjusts the model according to the front-rear suspensionstiffness experiment, the axle load testing of the whole car with unload and loadedsemi-trailer，tire testing and the stiffness experiment of the air spring of the kind of car.Build a semi-trailer tractor model that can do handing stability and driving stabilitysimulation analysis experiments instead of real vehicle. Verified the correctness of themodel by simulation analysis experiments，and the model can be used to researchvehicle driving stability and the secondary development of the model.In order to analysis the driving stability of the car，this article describes theintrinsic link of the handing stability and driving stability，and finds that handingstability contains part of the driving stability. Uses the model，this article analysis thesteady static circular test，return ability rest，pylon course slalom test and steeringtransient response test performance，and scoring the simulation and experimental resultsaccording to the national standard of the experimental method of vehicle handingstability. The results show that the heaver-duty semi-trailer tractor has a good handingstability and driving stability both in unload and loaded， and also verifies thecorrectness of the design. The article studied the influence of the mass center location，wheelbase and saddle parameter of the semi-trailer to driving stability，with a view to providing reference for vehicle system design.The article established a front independent suspension body roll model with frontsuspension stabilizer bar and analyzed the influence of the front suspension stabilizerbar angle stiffness to driving stability based on ADAMS model of the heavy-dutysemi-trailer tractor.