Abstract: In order to solve the problem that efficiency of the powertrnin of the vehicle is very low, especially under the heavy load, the method of automatic shifting is realized to suit for the load, and improve the efficiency. It is important to find a suitable shifting strategy, Since the nonlinear function between the status of vehicle and optimal gear position, and corresponding data is given, neural network can be trained away from line with the acquisition data. The method of gear position decision for the vehicle based on optimal algorithm of BP neural network is studied. With the example of three parameter shifting strategy, the neural network is trained and the result of the simulation using MATLAB is given.

Key words: Vehicle Automatic shifting Neural network Gear position decision