Patent ID: 7722499

Claim:
A method for controlling a vehicle launch condition of a vehicle having a powertrain that includes a transmission having an input, a current gear, an input clutch associated with a target gear and an output, an engine and a first electric machine for driving the input, comprising the steps of: (a) using the engine and the first electric machine to drive the transmission input at a desired magnitude of torque; (b) determining a desired magnitude of torque capacity of the input clutch; (c) determining a crankshaft speed error; (d) determining a magnitude of a change in torque capacity of the input clutch that will reduce the crankshaft speed error; and (e) changing the torque capacity of the input clutch to a desired torque capacity whose magnitude is determined by adding the current magnitude of torque capacity of the input clutch and said change in torque capacity of the input clutch.