Starting-up Control Of Automated Manual Transmissions With Modeling Error Estimation

Automated manual transmission(AMT) is generally constituted by a dry clutch and a multi-speed gearbox, both equipped with electro-mechanical or electro-hydraulic actuators, which are driven by an electronic control unit. Because AMT retains the basic transmission structure of manual transmission, it has many advantages, such as simple mechanism, easy processing, low cost, high efficiency compared with other topologies of automatic transmission, which is in line with China’s national conditions, and widely applied to commercial vehicles and mini-cars.Starting-up control is the important and difficult control problem of AMT. Because of the dry clutch,AMT’s launch control is difficult to satisfy a smooth start at the same time meet the requirements of rapid start to reduce the friction work, which restricts the AMT’s application and promotion. In addition, the parameters of the vehicle itself and the driving conditions, such as the friction coefficient of clutch plate, vehicle weight, road conditions and road grade,are not fixed, which also caused great difficulties to AMT launch control. To solve those problems of AMT starting-up control, we proposed optimal control strategy with modeling error estimation. The control strategy using the linear quadratic regulator to optimize the engine speed, the speed difference between the clutch input and output, the impact of the drive train Simultaneously at the starting process. Moreover, the algorithm includes a model error estimator which estimates the model error caused by the changing of vehicle parameters and working conditions, and that estimated value is feedback to the control model so that the vehicle can still complete start successfully in the case of the parameters and operating conditions changing.In order to study the proposed control strategy, the work that has been done in this article is as follows:1. Application and Development of AMT has been researched, and the starting-up control algorithm of AMT is the focus of the research. The dry clutch structure, working principle and the evaluation Index AMT starting-up control has been analyzed, and then two control strategies of AMT starting-up was simply analyzed--constant engine speed control and optimal control.2. Through the above analysis of AMT starting process and control algorithms, the mission of this article was stated: optimal control of automated manual transmissions starting-up with modeling error estimation, and then the theoretical design of the control algorithm was done.3. The vehicle model and launch control algorithm model were built with professional software AMESim and AMTLAB/Simulink. The proposed control algorithm was verified by utilizing AMESim-Simulink co-simulation,and the simulation result was compared with that of the normal optimal control without modeling error estimation.4. Use d SPACE tools to build a real vehicle test environment, and then the algorithm was tested with real vehicle test. The test results show that the proposed algorithm not only meet the starting-up control process with different intention, but also completed vehicle starting successfully, smoothly and rapidly while the vehicle parameters and operating conditions has changed. The tests results show the practicability of the algorithm.