| Traction Control System(TCS) is a newfashioned electrical control which was developed in the middle of 80's.Through controlling the slip of the driven wheel, TCS can maintain the driving slip ratio in a stabilization zone which corresponds to the peak value of the friction factor.So it can prevent the driven wheel from slipping excessively when auto starts,accerelates or cornering, which can improve vehicle stability,handling and accerelation.It is a active automobile control technology.According to the above theory,focusing on the optimum longitudinal forces active control. TCS control logic and algorithm on split-μ and single-μ roads are established. The first, the throttle PID control means on single-μ based on the control of driven slip ratio is taken into ac—count.First of all, set the target slip ratio then cacluate the actual slip ratio from the vehicle dynamic models, according to their difference design the control rules and control engine accerelation pedal open so as to regulate the engine output torque.Sequentially make the value of driven slip ratio are around or equal to the target slip ratio, and made graphic model of NJ2045 vehicle with MATLAB/SIMULINK toolbox.then simulated the accerelation operating mode of NJ2045 vehicle with TCS and without TCS.The results of the simulation showed the vehicle with TCS can effectively improve the traction,handling and stability of the vehicle.The second,on split-μ road,we can regard the difference of driven-wheel speed as first threshold and rotate acceleretion as secondthreshold. Then, dynamic simulation models of vehicle system are established with Matlab/Simulink toolbox, and simulate several operating modes. Furthermore, Researches on factors which influence setting of acceleration threshold are proceeding with. The results show that TCS can effectively improve the driving ability of automobile. The mentioned above is the second part of the discourse.The first part is NJ2045 vehicle's dynamic models made with simulink,which comprises several key parts of vehicle,such as engine,transmission,tyre,and whole vehicle and etc.Engine model contain two parts.which are static state model and dynamic model, the former is modeled according to the speed characteristic experiment, then polynomial fitting these experiment data(output torque and engine speed);the latter is modeled by simplifying the engine dynamic process as once inertia system with lag tache; in the case of transmission, we think of clutch,gear-box,power transfer,transmission shaft and half shaft as the components whose function are only transferring the torque; tyre model adopt the UA theory model and the whole model employ the seven freedom model, which include longitudinal displacement,lateral displacement,sway angle displacement and four wheel's rotation movement that encircle their own axis. And these models are used to reflect the subsystem's influence on the dynamic of whole vehicle and observe the running statement of vehicle.Automatic gear shifting is the target which people are seeking over a long time. It is a significant sign of automobile evolving to the advanced stage and the important technology which desiderate developing and spreading. The automobile with automatic transmission (AT) has smooth gearshifting and convenient operation. Moreover it can automatically gearshift in term of optimal occasion, redounding to the improvement of dynamic performance and fuel economy. Furthermore, when the drive-wheel slip excessive,the ECU of TCS can communicate with the gearbox's ECU, the gear-box revises the gear-shift schedules through the gearbox's ECU. Order the gear-box upshift propriety,or when slipping occurs it can prevent down-shift automaticly.So it can guaratee the driven moment summons to the driven-wheel no more increasing, which is propitious to driven-wheel's an-ti slipping. Based on this theory, according to the acceleration ,the third part of the discourse give the dymamic schedule suitable for NJ2045 light-off vehicle based upon static two-parameter...
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