The Analysis Of Starting Control Characteristic For Automatic Mechanical Transmission Clutch And Test System Design

Automatic mechanical transmission(AMT)have many advantages,such as convenient operation,higher security,more powerful,lower cost and less environment pollution,so it is widely used in heavy vehicles.Automatic clutch is the core part of AMT transmission system and establish connection between engine and transmission,and the control performance of clutch have direct influence for AMT promotion and application.Clutch engaging process require smooth and soft to avoid vehicle sharking during starting.Clutch separation process require separate thoroughly and rapidly.And also reliable running and long service life for clutch is the basic requirements.So this paper launched a series of research around clutch automatic control.Following main contents are included in this paper:(1)Aimed at clutch accurately control and vehicle transmission performance improvement.Consulted a large amount of relevant reference at home and abroad.On this basis,detail control characteristic analysis of clutch starting process was conducted,including the load characteristics,torque transmission characteristic and control characteristic of starting process.Reached the load characteristic curve of clutch small end by curve fitting and established torque transmission model for diaphragm spring clutch.Clutch control method,engaging process and actuator working principle was analyzed.Simulation analysis for clutch actuator was conducted which based on gas modeling theory.Dynamics model for Clutch starting process was established which provided the theory basis for clutch starting control strategy set up.(2)Based on the theory analysis,the clutch starting control strategy was formulated.Starting control parameter of clutch was selected and the control method was confirmed.Clutch starting influence factor is researched which combined with clutch control performance index.The fuzzy control method was applied to judge driver intention and clutch target engaging speed.PID control and PWM modulation was applied to clutch actuator.Position tracking control by clutch actuator was realized.Starting simulation model of clutch was established which included engine model,clutch model,transmission model and control strategy model.Starting process simulation was finished within MATLAB and sumulink.The simulation results showed very good control results.(3)Based on the theory analysis for clutch starting process,test bed for clutch starting process was designed,including engine simulator,transmission device,AMT gearbox and inertia load simulator.Test bed control system was designed.Main controller and sensor for test bed was selected.The sensor signal was processed and hardware communication network was established.The communication function between the modules was realized.(4)The software for starting test system was designed which include main program for AMT,starting control program,sensor signal acquisition and processing program,communication program,etc.Clutch starting control strategy was applied to test bed and debugging test was made for clutch actuator.The debugging test for clutch starting process was finished and the test demonstrated the feasibility of starting control strategy.