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In order to improve the tractive ability, steering capability and directional stability, etc. of automated mechanical transmission (AMT) vehicles running on the wet and slippery road, the anti-slip regulation (ASR) technologies for AMT vehicles are developed. The significance of ASR for AMT vehicles is introduced; a road friction recognition method based on the deceleration of driving wheels is investigated; a fuzzy anti-slip control system based on adjustment of engine torque is developed and the corresponding experimental verification is conducted. The experimental results denote that the proposed method is effective to eliminate the excessive slip when the AMT vehicle travels on the low friction road.

With the rapid development of electronics and the growing demand for higher vehicle performance, driving environment recognition and self-adaptation are becoming more and more important for the vehicle control systems. A two-level intelligent real-time driving environment recognition architecture is proposed in this paper. The lower level does the fundamental recognition according to “driving condition” algorithms and the upper level makes inference and decision based on rules. Also, the application of the driving environment recognition in the automatic mechanical transmission (AMT) is introduced.

Up to now, during the automatic shift, the throttle opening of the engine usually has maintained a constant. But due to the sudden change of the gear ratio in shift process, the pull and the acceleration of the vehicle are also changed rapidly, which results in the reduction of vehicle performances and deterioration of shift qualities. For mechanical automatic transmission with non-power shift this problem becomes more serious. This paper brings forward some countermeasures to solve this problem, i.e., adjusting the throttle opening in shift process, using dynamical closed loop control, the speed difference between the synchronized gears in gearbox and the speed difference between the driving and the driven plates of the clutch can be reduced; and using sequence feedback control, the engine, the clutch and the gearbox will get the optimum matching by which the vehicle performances can be increased.

An automated mechanical transmission controlled by an optimized dynamic 3-parameter gear-shift schedule, which makes maximum use of the power-train potential and meets well with the optimal driving conditions of the vehicle, is developed in this paper. Two methods to calculate the 3-parameter controlled shift schedule are introduced-one of which is of graphic, and the other, of analytic. For the latter, the mathematical model of shift as well as an actual computer program is given, which is very accurate and convenient for use with the computer. To make full benefit of the 3-parameter-controlled shift schdule in getting better fuel economy, dynamic performance and favorable riding comfort, the throttle angle should be changed during shift which, too, is a break through when comparing with the constant throttle angle now used all over the world.

In order to improve the ease of operation, the fuel economy and the dynamic performance of an automobile, an automated mechanical transmission controlled by electronics has been developed. As the control of the clutch is stochastic, complicated and changeable, the realization of the optimum engagement schedule of the clutch is the most important technique in the system. This paper uses high-speed switching valves which are simple in structure, and the clutch is controlled by pulse width modulation (PWM), thus greatly reducing the cost. The paper analyses the linear range and wave error of the switching valve system (SVS) and gives a quantitative basis to the parameter selecting of the switching valve system. A regulator with good performance has been designed by simulation. The experiment results show that it has reached the expected requirements.

In the paper, by practical dynamic process instead of steady assumption, mathematical model in a meticulous way and the overall optimization for the design variables, it is applicable to determine the optimum performances for power transmission system. At the same time, according to typical driving cycle for the vehicle fuel economy is taken as objective function and the dynamic performance as restraint so that the rational coordination of fuel economy and dynamic one can be achieved. Finally, the optimum result shows that it is in a closs agreerment with the test result.