Abstract: A hybrid powertrain includes a control unit that regulates electric power interchange an energy storage device and a motor/generator for causing selective torque generation by the motor/generator and for controlling engagement of torque-transmitting mechanisms. The control unit is configured to place the torque-transmitting mechanism in slipping engagement to launch the vehicle and thereby decouple a fixed relationship between engine torque and motor/generator torque or between engine torque and torque at the output member. A method of operating a hybrid vehicle powertrain is also provided.

Abstract: An electromechanical transmission is provided with a structural support member that supports a motor/generator in a space efficient way; particularly, the motor/generator is supported from one side only to save space axially in the transmission. Specifically, a stationary structural support member circumscribes an outer surface of and supports a stator while extending radially-inward of a rotor and at least partially supporting the rotor. A rotor hub rotatable with respect to the structural support member is used to support an inner surface of the rotor. The structural support member substantially encloses the stator and rotor from one direction along the axis of rotation. However, the stator and rotor have no additional support members in the opposing axial direction such that they are unenclosed from an opposing axial direction.