Effects Analysis On The Performance And Detection Study Of Axial Deviation Angle Of Tractor-trailer

Effects Analysis on the Performance and Detection Study of Axial Deviation Angle of Tractor-trailerWith the increasing widespread application of tractor-semi trailer, problems of driving safety, handling stability and so on were also becoming more prominent. The driving and handling stability, and the driving safety of high-speed and curve of tractor-semi trailer that were influenced seriously by axial deviation angle, increasing the width of driving passage and tire wear, brought about hidden trouble. It has academic meaning and practical value to study on detection methods and effects analysis on the performance of axial deviation angle of tractor-trailer, it can enhance the initiative security.Based on the analyses of international researchers'researches on handling stability of tractor-semi trailer quantitatively, in order to make a comprehensive study on the mechanism of effects of axial deviation angle on driving stability of tractor-semi trailer, in this paper, dynamics and kinematics analysis of the tractor-trailer system was carried out with the application of virtual prototyping technology. The mathematical model of driving stability of tractor-semi trailer and virtual prototype were established. Then the effect of axial deviation angle on driving stability of tractor-semi trailer was further explored, and the detection methods of axial deviation angle were involved. The research mainly included the following aspects.(1)In this paper, the axial deviation angle was interpreted, the deviation causes of carrying axletree were introduced briefly from manufacturing and maintenance; at the same time, the mechanism of effects of axial deviation angle on the performance of straight line driving, braking, handling stability and tire wear were analyzed qualitatively with the application of relevant theory of dynamics and kinematics, the necessity and feasibility of study on effects on the performance of axial deviation angle of tractor-trailer were discussed as well.(2)In this paper, applied with the tractor dynamics principle, dynamic and kinematic analyses of driving stability were analyzed considering evaluation parameters, tire properties and freedom degrees. Steady-state steering characteristics and transient response characteristics of angle step input of the tractor-trailer were analyzed, and the steady-factor' influence about steering was discussed. The basic theory of braking stability was analyzed.(3) In this paper, two detection methods was studied. â‘ The detection method of semi-trailer carrying axletree deviation angle based on machine visual, adopting the machine visual method to capture the print of the tyre and the panorama picture of the semi-trailer. Using the matlab software to carry through the disposing of the image, got the printed centre of the axle and the angle between steering orientation and detecting platform's centre line of the semi-trailer. And use the data to work out the result of the carrying axletree deviation angle of the semi-trailer. The emphasis was to analyze and compare with the different kinds of classical operators for edger detecting. At last, choose the fitting canny operator as the operator of the detecting system.â‘¡The detection method of semi-trailer carrying axletree deviation angle based on laser ranging technology, the detection trestle was fixed to the draft key vertically. The laser range finder was fixed on the bottom of the detection trestle and emitted laser, measuring the horizontal projection distance between the left and right edge in front and behind of the wheels and the point of semi-trailer draft key. The rotation angle of laser range finder was measured by the photoelectric encoder, according to the value of the distance and angle to calculate the semi-trailer axial deviation angle. The emphasis was the introduction of laser ranging and advanced sensor technologies, the precision, efficiency and adaptability were enhanced.(4) In order to analyze the effects of axial deviation angle on the performance of tractor-semi trailer, the object for study was actual model in this paper. After analyzed and simplified in a certain extent, separately the chassis models, steering system model, draft model, suspension model, tires and ground were established, and steering drive, drive torque and braking torque were added, thereby the whole model of tractor-semi trailer was established. Through the PID controller, the speed and the braking force of tractor-semi trailer were controlled.(5) According to national standards, the typical steady-state steering and braking tests were applied to real vehicle and virtual prototype simulation tests. The five rounds of device, wireless accelerometer, wireless strain sensors, potentiometers and other advanced equipments were applied to real vehicle tests; they all had high precision and sensitivity. Through tests, the correctness of the model was verified. The conclusion was got that the tractor-semi trailer virtual prototype had good consistency with the real vehicle, after comparing and analysis of test results between real vehicle tests and virtual prototype simulation tests.(6)In this paper, it was attempted to adopt a new analysis method-experimental design technology that was a relatively mature technology. The tests processes were planned rationally and the tests results were analyzed statistically. The parameters analysis tests could be completed with the application of experimental design in various operating conditions. The test system has high simulation, high reliability, full working condition and other characteristics, providing a new research and test method for the research and design of tractor-trailer.(7)According to the kinematics and dynamics theory and the virtual prototype, four typical working conditions of straight line driving maintenance, braking performance, steering performance, and transient yaw response characteristics were simulated and analyzed. The typical measurement indicators were analyzed also in all conditions, and the impact assessments were quantized, finally the conclusion could be drawn that axial deviation angle has a obvious impact on the performance of tractor-semi trailer. And it has a theoretical significance and the practical application value to optimize tractor-semi trailer structure and raise the technical level of parametric detection and diagnosis.The research and the development work made by this paper is an application of functional virtual prototyping modeling and simulation and practice. Some research fruit is achieved in some areas such as research realization technology and parametric analysis. It has theoretical and practical application value for improving the detection and study technology. At the same time, this paper leads virtual prototyping experimental design techniques into the detection of tractor-trailer performance, realizes the parametric and multi functions process of detection. The results of this paper play a positive role in the development of the tractor-trailer detection.