Patent ID: 6220987
Filing Date: 2001-04-24
Classification: F16H,Y10T

Abstract:
A method for controlling a vehicular powertrain including an internal combustion engine and an automatic transmission having a plurality of selectable input to output speed ratios, and a controller in communication with the internal combustion engine, the transmission, and an accelerator pedal, the method comprising:determining a driver requested wheel torque based on position of the accelerator pedal;determining a value indicative of current barometric pressure;determining a current input to output speed ratio;modifying the driver requested wheel torque based on the current barometric pressure and the current input to output speed ratio to determine a compensated wheel torque;determining a vehicle speed ratio-changing threshold based on the compensated wheel torque and the current input to output speed ratio;determining a current vehicle speed;comparing the current vehicle speed to the vehicle speed ratio-changing threshold; andgenerating a command to change the input to output speed ratio when the current vehicle speed crosses the vehicle speed ratio-changing threshold wherein the selected ratio is based on the compensated wheel torque.