Patent ID: 8359144
Filing Date: 2013-01-22
Classification: B60W,B60Y,F16H,Y10T

Abstract:
1. Method for operating a powertrain system including a torque machine mechanically rotatably coupled via a transfer gear set to a drive wheel, the transfer gear set comprising a first gear meshingly engaged to a second gear, the transfer gear set including a lash angle between the first and second gears, the method comprising: monitoring an output speed associated with the torque machine and a wheel speed associated with the drive wheel; detecting a transition between a first torque transfer state and a second torque transfer state, the transition including a gear lash event across the transfer gear set; setting an elapsed time period for completing the gear lash event across the transfer gear set during the transition between the first torque transfer state and the second torque transfer state; determining a target output speed derived from the wheel speed during and at the end of the elapsed time period; determining a preferred output speed profile during the gear lash event, the preferred output speed profile comprising prescribed changes in the output speed associated with phase-shifting the lash angle from a minimum lash angle to a maximum lash angle and adjusting the output speed to be substantially equal to the target output speed at the end of the elapsed time period; and controlling the torque machine to achieve the preferred output speed profile.