To show the effectiveness of the model-based development of transmission control units, the gearshift calibration of an automated manual transmission is chosen as example. The shift quality calibration is typically performed in real vehicles on the road, where the calibration engineer has to try different control parameters till the subjective assessment on the shift quality meets certain requirements, such as shifting comfort or sportiness. However, compared with today's multiplying number of variants in vehicle-engine-transmission combinations and exponential growth of control parameters, this traditional method is backward and costly. In contrast to the conventional development shift quality calibration, the presented method uses a closed loop approach based on a dynamic model instead of human know-how. In the first step, a non-linear dynamic transmission model is built to describe the transient behavior during gear shifting in detail. Black box, grey box and white box models are combined and with the help of a test bench parametrised. Afterwards, the hydro-mechanical synchronisation system is used as an example, and a position trajectory based shift quality optimisation process is presented.
展开▼
