Abstract: A system comprises a computer including a processor and a memory. The memory includes instructions such that the processor is programmed to: estimate a slip condition corresponding to at least one vehicle wheel; and generate, via an explicit Nonlinear Model Predictive Control (NMPC) module, control data for operating the at least one vehicle wheel based on the estimated slip condition. The explicit Nonlinear Model Predictive Control (NMPC) module includes a feedforward control module that is configured to generate adjustment data based on the estimated slip condition, wherein the adjustment data modifies the control data.

Abstract: A system and method is disclosed for applying a counter torque to at least one axle of a motor vehicle, wherein the motor vehicle has an electronic parking brake (EPB) subsystem, to thus enhance a braking action of the vehicle while the EPB subsystem is engaged. In one embodiment the system may have an all wheel drive (AWD) system configured to process electronic information received by the AWD system that informs the AWD system that the EPB subsystem has been engaged, and to then apply a counter torque to the at least one axle of the vehicle. The system may also at least one of release the counter torque after receiving electronic information informing the AWD system that the EPB subsystem has been disengaged, or return to a torque value required for AWD system operation.

Abstract: A drive train having a locking differential and a control unit for controlling operation of the locking differential. The control unit is responsive to selected vehicle characteristics to sua sponte activate or inactivate a locking mechanism of the locking differential to cause the locking differential to operate in a locked manner or an unlocked manner, respectively. A method for operating a locking differential is also provided. The method includes: utilizing only preselected vehicle criteria indicative of the operational state of the vehicle to identify a situation in which a locking mechanism associated with the locking differential is to be energized; and responsively energizing the locking mechanism.

Abstract: A system and method is disclosed for applying a counter torque to at least one axle of a motor vehicle, wherein the motor vehicle has an electronic parking brake (EPB) subsystem, to thus enhance a braking action of the vehicle while the EPB subsystem is engaged. In one embodiment the system may have an all wheel drive (AWD) system configured to process electronic information received by the AWD system that informs the AWD system that the EPB subsystem has been engaged, and to then apply a counter torque to the at least one axle of the vehicle. The system may also at least one of release the counter torque after receiving electronic information informing the AWD system that the EPB subsystem has been disengaged, or return to a torque value required for AWD system operation.

Abstract: A drive train having a locking differential and a control unit for controlling operation of the locking differential. The control unit is responsive to selected vehicle characteristics to sua sponte activate or inactivate a locking mechanism of the locking differential to cause the locking differential to operate in a locked manner or an unlocked manner, respectively. A method for operating a locking differential is also provided. The method includes: utilizing only preselected vehicle criteria indicative of the operational state of the vehicle to identify a situation in which a locking mechanism associated with the locking differential is to be energized; and responsively energizing the locking mechanism.

Abstract: A power transmission device includes a friction clutch operable to selectively transfer torque between an input member and an output member. An actuator is operable to provide an actuating force to the friction clutch. The actuator includes an electric motor having an output shaft drivingly coupled to a pump. The pump is operable to provide pressurized fluid to a piston acting on the friction clutch. A controller that is switched on and off in response to an ignition signal estimates the temperature of the friction clutch at the time of being switched on based on a time the controller has been off. A method of estimating a temperature of the friction clutch is also disclosed.

Abstract: A power transmission device includes an actuator having an electric motor driving a pump to supply pressurized fluid to a piston acting on a friction clutch to transfer torque between rotatable input and output members. In one instance, a valve between the pump outlet and the piston selectively traps pressurized fluid acting on the piston without continued energization of the electric motor. A gerotor may be formed from a material having a first coefficient of thermal expansion and a housing formed from a material having a second lower coefficient of thermal expansion to vary pump component clearances as the viscosity of the pumped fluid changes with changes in temperature. A method of controlling the power transmission device includes defining a correlation between pump speed, fluid temperature and fluid pressure, determining fluid temperature, determining pump speed, and rotating the pump to transfer a predetermined quantity of torque.

Abstract: A drive train having a locking differential and a control unit for controlling operation of the locking differential. The control unit is responsive to selected vehicle characteristics to sua sponte activate or inactivate a locking mechanism of the locking differential to cause the locking differential to operate in a locked manner or an unlocked manner, respectively. A method for operating a locking differential is also provided. The method includes: utilizing only preselected vehicle criteria indicative of the operational state of the vehicle to identify a situation in which a locking mechanism associated with the locking differential is to be energized; and responsively energizing the locking mechanism.

Abstract: A power transmission device includes a rotatable input member, a rotatable output member, a clutch assembly to selectively transfer torque between the input member and the output member, and a controller for controlling the clutch assembly. The controller controls the clutch assembly based at least partly on a torque request.

Abstract: A power transmission device includes a rotatable input shaft, a rotatable output shaft and a ring gear fixed for rotation with the input shaft. A carrier is fixed for rotation with the output shaft. A pump assembly includes an inner rotor supported for rotation on the carrier and an outer rotor encompassing the inner rotor. The outer rotor is in driving meshed engagement with the ring gear. The pump provides pressurized fluid to one of first and second fluid ports. A flow restrictor is moveable to selectively restrict fluid flow relative to one of the first and second ports.

Abstract: A power transmission device includes a rotatable input member, a rotatable output member, a clutch assembly to selectively transfer torque between the input member and the output member, and a controller for controlling the clutch assembly. The controller controls the clutch assembly based at least partly on a torque request.

Abstract: A power transmission device includes a rotatable input member, a rotatable output member, a friction clutch to selectively transfer torque between the input member and the output member, an actuator providing an actuating force to the friction clutch and a controller. The actuator includes an electric motor having an output shaft drivingly coupled to a gerotor. The gerotor is operable to supply pressurized fluid to a piston acting on the friction clutch. The controller controls the actuator in response to a four-wheel lock request to provide one of a minimum output torque and an output torque greater than a vehicle requested torque to operate the friction clutch in a locked mode.

Abstract: A power transmission device includes a rotatable input shaft, a rotatable output shaft and a ring gear fixed for rotation with the input shaft. A carrier is fixed for rotation with the output shaft. A pump assembly includes an inner rotor supported for rotation on the carrier and an outer rotor encompassing the inner rotor. The outer rotor is in driving meshed engagement with the ring gear. The pump provides pressurized fluid to one of first and second fluid ports. A flow restrictor is moveable to selectively restrict fluid flow relative to one of the first and second ports.

Abstract: In one form, the present teachings provide a power transmission device that includes a rotatable input shaft, a rotatable output shaft and a ring gear fixed for rotation with the input shaft. A carrier is fixed for rotation with the output shaft. A pump assembly includes an inner rotor supported for rotation on the carrier and an outer rotor encompassing the inner rotor. The outer rotor is in driving meshed engagement with the ring gear. The pump provides pressurized fluid to one of first and second fluid ports. A flow restrictor is moveable to selectively restrict fluid flow relative to one of the first and second ports. In another form, the present teachings provide a power transmission device with a ring gear and a carrier assembly that are coupled to first and second rotary members, respectively. The carrier assembly includes pump assemblies, each of which having a rotor pin, an inner rotor rotatably received on the rotor pin, and an outer rotor that is rotatably received over the inner rotor.

Abstract: A power transmission device includes a rotatable input member, a rotatable output member and a friction clutch positioned within a housing. The friction clutch is operable to selectively transfer torque between the input member and the output member. A torque tube has a first end fixed to the friction clutch housing and a second end adapted to be fixed to an axle housing. The rotatable output member is supported to rotate within the torque tube and adapted to drivingly engage a rotatable member of an axle housing.

Abstract: A power transmission device includes a friction clutch operable to selectively transfer torque between an input member and an output member. An actuator is operable to provide an actuating force to the friction clutch. The actuator includes an electric motor having an output shaft drivingly coupled to a pump. The pump is operable to provide pressurized fluid to a piston acting on the friction clutch.

Abstract: A power transmission device includes a rotatable input shaft, a rotatable output shaft and a ring gear fixed for rotation with the input shaft. A carrier is fixed for rotation with the output shaft. A pump assembly includes an inner rotor supported for rotation on the carrier and an outer rotor encompassing the inner rotor. The outer rotor is in driving meshed engagement with the ring gear. The pump provides pressurized fluid to one of first and second fluid ports. A flow restrictor is moveable to selectively restrict fluid flow relative to one of the first and second ports.

Abstract: A drive train having an axle assembly with a differential and a multi-speed transmission outputs rotary power to an input pinion of the differential. The multi-speed transmission includes a positive or dog clutch with teeth having staggered heights. The staggered tooth height configuration provides a larger effective engagement area with less tooth lash.

Abstract: A power transmission device includes a friction clutch operable to selectively transfer torque between an input member and an output member. An actuator is operable to provide an actuating force to the friction clutch. The actuator includes an electric motor having an output shaft drivingly coupled to a gerotor. The gerotor is operable to provide pressurized fluid to a piston acting on the friction clutch.

Abstract: A power transmission device includes an actuator having an electric motor driving a pump to supply pressurized fluid to a piston acting on a friction clutch to transfer torque between rotatable input and output members. In one instance, a valve between the pump outlet and the piston selectively traps pressurized fluid acting on the piston without continued energization of the electric motor. A gerotor may be formed from a material having a first coefficient of thermal expansion and a housing formed from a material having a second lower coefficient of thermal expansion to vary pump component clearances as the viscosity of the pumped fluid changes with changes in temperature. A method of controlling the power transmission device includes defining a correlation between pump speed, fluid temperature and fluid pressure, determining fluid temperature, determining pump speed, and rotating the pump to transfer a predetermined quantity of torque.