A control system and method for controlling a multiple gear ratio automatic transmission in a powertrain for an automatic transmission having pressure activated fiction torque elements to effect gear ratio upshifts. The friction torque elements are synchronously engaged and released during a torque phase of an upshift event as torque from a torque source is increased while allowing the off-going friction elements to slip, followed by an inertia phase during which torque from a torque source is modulated. A perceptible transmission output torque reduction during an upshift is avoided. Measured torque values are used during a torque phase of the upshift to correct an estimated oncoming friction element target torque so that transient torque disturbances at an oncoming clutch are avoided and torque transients at the output shaft are reduced.

Methods and system are described for changing a driveline gear range from a higher gear range to a lower gear range. The driveline may include two electric machines and four clutches in a four wheel drive configuration. The methods and systems permit a driveline to change from a higher gear range to a lower gear range without stopping a vehicle.

A hybrid drive device includes an internal combustion engine, an electric machine and an impulse start module which comprises two clutches and a flywheel mass. A method for operating the hybrid device includes opening the first clutch of the impulse-start module and establishing a start-up requirement for the internal-combustion engine. The method also includes closing the first clutch with the second clutch in an open or closed position for a start of the internal-combustion engine.

A control system (208) for enabling deactivation of vehicle creep in a vehicle (10) with an engine (202), the control system (208) comprising one or more controllers (300), wherein the control system (208) is configured to: enable vehicle creep (402) so that wheel drive torque can reach a first value greater than zero without a driver load request and without a brake request, wherein enabling vehicle creep comprises the engine (202) being active while connected to a vehicle wheel (FL, FR); monitor for a vehicle creep deactivation signal (404); and in response to the vehicle creep deactivation signal (404), inhibit vehicle creep (412) so that wheel drive torque cannot reach the first value without a driver load request, and wherein inhibiting vehicle creep comprises causing disconnection (414) of the engine (202), at least in part, from the vehicle wheel (FL, FR).

The control device of the vehicle performs slip control for engaging the connection and disconnection clutch as an instruction hydraulic pressure for engaging the connection and disconnection clutch by the hydraulic control mechanism after the internal combustion engine is started by the starter, as an instruction hydraulic pressure for maintaining the speed of the internal combustion engine at a higher speed than a lower limit speed for avoiding the stop of the internal combustion engine. Further, the control device of the vehicle performs engagement completion control of raising an instruction hydraulic pressure for engaging the connection and disconnection clutch from an instruction hydraulic pressure in the slip control to an instruction hydraulic pressure for completing engagement of the connection and disconnection clutch when a difference between the speed of the internal combustion engine and the speed of the electric motor becomes smaller than a preset threshold value.

A method for operating a drive train having a starting component between an electric machine and an output shaft of a transmission, and a separating clutch between an internal combustion engine and the electric machine, with a rotor of the electric machine being coupled to the input shaft of the transmission, where the method initially drives a motor vehicle solely by the electric machine while the starting component is engaged or slipping and the separating clutch is disengaged. The method then engages the separating clutch to crank the internal combustion engine. The method disengages the separating clutch after cranking, with an output-side rotational speed of the separating clutch being lower than an idling speed of the internal combustion engine. Subsequently, the method engages the separating clutch to drive the motor vehicle with the internal combustion engine when a target drive torque reaches or exceeds a limit.

A transmission includes an input shaft coupled to a prime mover, a countershaft, main shaft, and an output shaft, with gears between the countershaft and the main shaft. A shift actuator selectively couples the input shaft to the main shaft by rotatably coupling gears between the countershaft and the main shaft. The shift actuator is mounted on an exterior wall of a housing including the countershaft and the main shaft. A controller controls the shift actuator utilizing an actuating pulse and an opposing pulse.

A vehicle control device controls a vehicle including an internal combustion engine, an electric motor, a drive wheel, and a lock-up clutch provided in a power transmission path from the internal combustion engine and the electric motor to the drive wheel. The vehicle control device is configured to: not execute a motor vibration damping control and a slip vibration damping control in a non-vibration damping region; execute the motor vibration damping control and the slip vibration damping control in a first vibration damping region in a high load state or a low rotation speed state; and execute the motor vibration damping control and not execute the slip vibration damping control in a second vibration damping region in a medium load state or a medium rotation speed state.

A method actively changes the frictional value of a hybrid disconnect clutch installed in a powertrain of a vehicle in which a first electric motor (18) is connected to a clutch input (21) and an internal combustion engine (17), and a second electric motor (19) is connected to a clutch output (22) and a vehicle output (23). The frictional value of the hybrid disconnect clutch is actively changed, in order to roughen a surface of the friction linings on the hybrid disconnect clutch (20). A slip situation is established at the hybrid disconnect clutch (20), and during this slip situation energy is introduced into the hybrid disconnect clutch (20) in a controlled manner.

A transmission includes an input shaft coupled to a prime mover, a countershaft, main shaft, and an output shaft, with gears between the countershaft and the main shaft. The shift actuator is mounted on an exterior wall of a housing including the countershaft and the main shaft. A shift control circuit operates a shift actuator using a first opposing pulse command and a first actuating pulse command, and releases pressure with shift actuating and opposing volumes of the shift actuator upon determining a shift completion event.