Patent ID: 7678013

Claim:
A method for controlling the launch of a vehicle having a powertrain that includes a first power path for driving a first wheel set and including an engine, a transmission having an input driveably connected to a crankshaft of the engine, a current gear, an input clutch associated with the current gear and an output connected to first wheel set, and a second power path including an electric machine for driving a second wheel set, comprising the steps of: (a) determining a desired magnitude of wheel torque to be produced at the first wheel set; (b) using the desired magnitude of wheel torque to be produced at the first wheel set to determine a magnitude of crankshaft torque; (c) producing a predetermined magnitude of torque capacity at the input clutch; (d) determining a crankshaft speed error; (e) determining a change in magnitude of torque at the crankshaft that will reduce the crankshaft speed error; and (f) operating the engine to produce a desired engine torque, whose magnitude is determined from the change in magnitude of torque at the crankshaft and the magnitude of desired crankshaft torque.