关键词: CAN总线, SAE J1939标准, 换挡品质, 自动变速

Abstract: According to the need of automated mechanical transmission’s automatic shifting, how the application of CAN bus in the power-train system to affect shift time, jerk and abrasion of clutch is analyzed , the details and communication process of message applied in the control system is expatiated, the communication software for receiving and sending message by bus is made. On this base, a control module based on an application layer protocol-SAE J1939 of CAN bus is designed. The module realizes the sharing of engine speed and accelerator pedal position between electric diesel and automated mechanical transmission; at the same time, it can control the output torque and engine speed of diesel in the process of shifting. The test result shows that the coordination control technology make the hardware of automated mechanical transmission more simple because of the matching of the diesel’s output characteristic and the transmission’s shift process. The shift time is shortened. The abrasion of clutch is decreased. So the shift quality is improved.

Key words: Automatic shifting, CAN bus, SAE J1939 standard, Shift quality