Patent ID: 8412396

Claim:
A method for providing an electric-only (EV) launch mode in a vehicle having an accelerator pedal, an engine having a crankshaft, a motor generator unit (MGU), a dual-clutch transmission (DCT) with an odd-gear clutch and an even-gear clutch, wherein the vehicle is adapted for selectively rotating the crankshaft using motor torque from the MGU, the method comprising: using motor torque from the MGU, while the engine is off, to increase a rotational speed of the crankshaft to above a calibrated minimum EV launch speed when a threshold minimum force is applied to the accelerator pedal; minimizing engine compression via a controller while increasing the rotational speed of the crankshaft; controlling an operation of a designated clutch of the odd-gear clutch and the even-gear clutch according to a predetermined torque function until input torque to the DCT equals or exceeds a calibrated level; slipping the odd-gear clutch or the even-gear clutch that is not designated, while increasing the rotational speed of the crankshaft, in order to dampen drivetrain oscillations; and launching the vehicle in the EV launch mode via the designated clutch when an input speed to the DCT exceeds a function of engine speed.