Method for gear selection during driving of a vehicle in a heavy uphill drive condition

摘要

A method for gear selection during driving of a vehicle in a heavy uphill drive condition is provided, the vehicle including an engine, an automated mechanical transmission, a clutch, a control unit for receiving input signals including signals indicative of vehicle speed, engaged ratio of the transmission, rotational speed of the engine, rotational speed of a input shaft and displacement of a throttle control for engine torque request, and for processing the signals in accordance with programmed logic rules to issue command output signals to the engine, to the transmission and to said clutch. When sensing a heavy uphill drive condition a target gear is determined for the uphill drive condition, the target gear being the highest possible gear with lowest possible gear ratio where the vehicle, in view of at least current circumstances, will be at least theoretically able to hold a constant vehicle speed or accelerate at least slightly, and where further selection of downshifts will be adapted so that no lower gear than the target gear will be selected and engaged.