Shifting Control Of AMT Vehicle Based On Driver’s Intention

The automation of transmission operations can effectively improve the vehicleperformance such as good power capability, economical fuel consumption, by whichdriver fatigue and work intensity due to long distance can be reduced. Thereforeshiftrules are the core of the automatic transmission control system, which related to thewhole transmission performance, its merit directly affect the vehicle’s power capability,economical fuel consumption and ride comfort.Process analysis of AutomaticMechanical Transmission System’s Gear-shifting and the shifting control strategyconditioned on intention of driver are prime study content in this paper.By identifyingthe driver’s intention, the shifting control strategy under different driving intention isestablished, which realized transmission’s synthetic shift control according to driverintention recognition.In this paper, focused on shifting control law of ATM system based on SC7130isput forward as follows:①The structure and principle of Automatic Mechanical Transmission shiftingcontrol System is introduced, and the status and the application at home and abroad aresummarized. On the basis of the research and conclusion, the content and flow of thispaper is confirmed.②Vehicle power-train model is established and vehicle engine torque andfuelconsumption characteristics are analyzed. In order to improve the shift quality, theclutch iscontrolled in the process of shifting which based on AMT synthetic shiftcontrol system.③According to the dynamic analysis during vehicle operating, driver’s intentionscharacteristics is extracted, the balance throttle for keeping speed and relative throttleunder straight road are defined, and the driver’s intention under straight road is dividedinto five interrelated classes.Based on driver’s intentions characteristics comprehensivejudgment, the rule of fuzzy inference is made, the Multiple-Input-Single-Output driver’sintentionrecognition model is established and verified by simulation.④According to the quantitative driver’s intention and the driver style, the currentmoment shifting power factor is determinedin acceleration condition;compromisebetween optimal power performance and optimal economic performance based on theshifting power factor, the optimal shift rule under driving intention is determined.In order to avoid shift cycle in deceleration condition, the shifts up points are modified. Ifthe current throttle is less than the balance throttle of higher gear, the control systemprohibits shift-up. Through comprise the simulation results of traditional shift schedule,the effectiveness of control strategy is verified.⑤Through analysis the vehicle’s lateral characteristics under corner condition, theoperation characteristics under corner condition are extracted, and then fuzzyidentification method based on wheel speed is established. According to identified theurgency of bend, the current gear is modified by threshold method, andthe simulationresults show that the control strategy can effectively solve shift-cycle and unexpectedshifting problem.