Search Results

For the vehicle equipped with stepped automatic transmission (SAT) that has a fixed number of gears, gearshift schedule is crucial to improve the comprehensive performance that takes into account power performance, fuel economy, and driver’s performance expectation together. To optimize and individualize the gearshift schedule, an optimization method and an improved performance evaluation approach for multi-performance gearshift schedule were proposed, which are effective in terms of reflecting the driver's expectation on different performance. However, the proposed optimization method does not consider the influence of the road slope on the comprehensive performance. As the road slope changes the load of vehicle that is different from the load when a vehicle runs on a level road, the optimized gearshift schedule without considering road slope is obviously not the optimal solution for a vehicle equipped with SAT when it runs on ramp.

Gearshift schedule of stepped automatic transmission (SAT) determines the timing when the gearbox should be shifted from a certain gear position to an adjacent one, which directly affects the performance of complete vehicle. To optimize the comprehensive performance considering power performance, fuel economy, and driver’s performance expectation, the formulation of gearshift schedule needs to take into account a number of factors such as the expression of different performance indices, the identification of driver’s intention on each sub-performance, and the adaption to driving conditions especially the road slope and curve. Based on our previous work, this investigation is focused on the adaptability of the gearshift schedule to curves of the road that could ensure the safety of vehicle and meanwhile maintain an optimal comprehensive performance reflecting a specific driver’s performance expectation.