| The automatic transmission technology of automobile is always the target that people pursue. It is a important aspect to reform and perfect the vehicle powertrain. The automatic transmission of automobile is divided into AutomaticTransmission(AT),AutomaticMechanicalTransmisson(AMT),Conti nuously Variable Transmisson(CVT).Automatic Mechanical Transmisson have the advantages such as simple machinery.high efficiency ,low cost and easy manufacture.The research and production of it has been listed into national "9.5" tackle key item of science and technology.This text combines the former research, make the following work:1 According to the former evaluation method, put forward the dynamic evaluation method of shift schedule. Shift schedule is the regulation that the time of automatically shifting between two shift changes with the control parameter's variety. As to the automatic transmission automobile, shift schedule decides whether the automobile shifts on the best shifting point, decides the exerting extent of the vehicle performance. Shift schedule has great influence on the performance of the vehicle, and different shift schedule has different influence, therefore we hope to look for the shift schedule which is of more benefit to develop the automoblie's functions by comparing and evaluating the different shift schedules, so, the evaluation of shift schedule comes to more important. The basic principle of that method is as follows:1) The evaluate method of dynamical performance: Suppose the time which the we cost to accelerate the vehicle to certain pre-arranged speed v on some driving load is t, moreover according to the best engine dynamical curve the time that it takes to drive the vehicle to the pre-arranged speed v on the driving load is to.The ratio t/to reflects the utilizing condition of the engine dynamical performance. Otherwise to different shift schedule, it is reflected that the t/to value is less, the dynamical performance is better than one in other shift schedules, it is more approach 1,it shows that the utilization of the engine dynamical performance is better.IV2)The evaluate method of economy: Suppose the fuel quantity which the vehicle cost to run some distance s on certain driving load is Qs, moreover the fuel quantity which the vehicle cost to run to pre-arranged distance s in the best engine economical curve is Qso and we get by the principle that the vehicle output power Pe is equal. The ratio Qs/Qso reflects the utilizing condition of the engine economical performance. It can be used to evaluate the fuel economy in different shift schedules. The value is less, the economical performance is better than one in other shift schedules, it is more approach 1it shows that the utilization of the engine economical performance is better.2 the analyse of shift superpose and shift circle:Shift superpose and shift circle are connected close with shift schedule. Shift characteristic is the relation of acceleration and speed, traction and speed, fuel consume and speed in the course of shifting on each throttle opening. It is also the characteristic that the driving torque on the wheel, acceleration and fuel consume change with the throttle opening and vehicle speed before and after shift. The purpose of confirm the value of shift superpose is to ensure the vehicle couldn't incorrect continual shift on the basis of the throttle wobble and the small fall of vehicle speed. This text makes pilot study to the fall of vehicle speed and accelerograph wobble in the course of shift.3 the setting of the simulation system.The simulation system is programmed by Microsoft Visual C++, MultiGen and OpenGVS are utilized in the building of the modeling of road vision. the main function it have is as follows:1) It can show the road vision on the different load.2) It can shift automatically during the vehicle running.3) It can show the parameter such as running distance, time, acceleration shift and fuel consume etc. on real time, and these data are saved into files in order to analyse la... |
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