Abstract: A stability control system for a vehicle that has an electric traction motor that provides torque to an axle through a differential. The traction motor responds to an instability event that is sensed by sensors on the vehicle by initially reducing the torque provided to the traction wheels to regain steering control. The traction motor then pulses increased torque in sequence with the application of braking force to provide enhanced direct yaw moment control.

Abstract: Methods and systems are provided for operating a driveline of a hybrid vehicle that includes an internal combustion engine, an electric machine, and a transmission are described. In one example, regenerative torque and torque of an electronically controlled differential clutch are adjusted to increase utilization of a vehicle's kinetic energy.

Abstract: A table of engine torque correction factors is used to compensate for noise factors. In a hybrid vehicle, the motor is used to measure engine torque during periods of constant transmission input shaft torque. By comparing the measured input torque to the requested engine torque, a controller can update the table of correction factors to compensate for changes in the noise factors. A service procedure may be implemented that systematically provides the controller an opportunity to update many values in the table.

Abstract: A hybrid electric vehicle having one or more controllers, at least two independently driven electric machines (EMs) that are each coupled to separate drive wheels, and controllers configured to generate a torque split ratio responsive to lateral acceleration and/or unequal friction coefficients detected during braking, and to generate electric power with the motors by regeneratively braking each wheel with unequal torques adjusted by the ratio, such that combined wheel braking torques do not exceed a total braking torque limit for the vehicle. In some configurations, the controller(s) generate the torque split ratio by a predetermined lookup table that maps a plurality of torque split ratios to lateral accelerations, the coefficients, and other parameters. Further arrangements include the controller(s) coupled with sensors that detect wheel slip and yaw rate, and responsive to a braking signal, the controller(s) disengage regenerative braking when the wheel slip and/or vehicle yaw are detected.

Abstract: An electrified axle system includes a pair of wheels, a super positioning torque vectoring differential coupled between the wheels, and a controller. The super positioning torque vectoring differential includes a traction motor and a vectoring motor. The controller operates the vectoring motor in speed control mode to reduce a speed difference between the wheels responsive to the difference exceeding a threshold, and operates the vectoring motor in torque control mode responsive to the difference falling within a target range and an accelerator pedal position achieving a value that depends on lateral acceleration associated with the system.

Abstract: A vehicle includes a pair of electric machines each coupled to a laterally-opposing wheel to output a wheel torque. The vehicle also includes a controller programmed to command a combined regenerative braking torque output of the electric machines based on a lesser of a braking torque limit of each individual electric machine. The controller is also programmed to command a regenerative braking torque from each electric machine to be within a predetermined torque threshold of each other in response to a yaw rate exceeding a yaw threshold.

Abstract: Methods and systems are provided for operating a hybrid vehicle during operating conditions where vehicle braking is requested. In one example, regenerative braking is permitted during conditions of wheel slip so that a greater portion of a vehicle's kinetic energy may be recovered and stored as electrical energy. Additionally, in some examples, the amount of regenerative braking is adjusted responsive to a torque of a differential clutch during wheel slip conditions.

Abstract: A vehicle includes an engine, an electric machine, a battery, and at least one controller. The vehicle may further comprise a port for supplying power to a load external to the vehicle. The controller is programmed to operate the engine at a power level based on a difference between a battery voltage and a reference voltage such that a power output by the electric machine reduces the difference. The power level may define an engine operating point that minimizes fuel consumption. The operating point may be an engine torque and an engine speed. The power level may be further based on a state of charge of the battery. The electric machine may be operated to cause the engine to rotate at an engine speed corresponding to the selected power level. The difference may be caused by varying power drawn by a load external to the vehicle.

Abstract: A vehicle includes a powertrain, an electric machine, a battery, and a controller. The powertrain is configured to transfer motive power to the electric machine to charge the battery during regenerative braking. The controller programmed to, in response to a decreasing demanded powertrain output torque, adjust a regenerative braking torque limit based on an anti-jerk torque schedule, generate an actual regenerative braking torque based on system constraints, and limit the actual regenerative braking torque to the regenerative braking torque limit.

Abstract: Methods and systems are provided for operating a hybrid vehicle during operating conditions where vehicle braking is requested. In one example, regenerative braking is allocated to vehicle wheels responsive to actual and estimated vehicle yaw. Additionally, friction braking torque is allocated to vehicle wheels responsive to requested braking torque and regenerative braking torques.

Abstract: A vehicle may include an engine selectively coupled to a motor and a transmission. The vehicle may include a controller configured to, in response to actuation of a brake pedal, command the transmission to downshift during a regenerative braking event based on a regenerative braking downshift torque. The regenerative braking downshift torque may be determined from a predicted brake pedal input rate. The predicted brake pedal input rate may be based on road grade, vehicle headway range and a driver history. The predicted brake pedal input rate may be classified as Low, Medium, or High. The regenerative braking downshift torque may also be determined from a predicted brake torque rate that is based on a predicted deceleration rate of the vehicle, a vehicle speed prediction and a road grade prediction within a future time interval that begins upon actuation of the brake pedal.

Abstract: A vehicle includes an electric machine, battery, torque converter bypass clutch, drive wheel, and controller. The electric machine is configured to recharge the battery via regenerative braking. The torque converter bypass clutch is disposed between the electric machine and the drive wheel. The controller is programmed to, in response to a negative drive wheel torque command during a regenerative braking event, adjust a closed-state torque capacity of the torque converter bypass clutch based on the torque command.

Abstract: Systems and methods for transitioning a torque source between speed control and torque control modes during a vehicle creep mode are disclosed. In one example, torque of an electric machine is adjusted in response to a torque converter model. The torque converter model provides for a locked or unlocked torque converter clutch.

Abstract: A method of operating a vehicle having a continuously variable transmission to simulate a step-ratio transmission. The method includes increasing an output torque based on a modified accelerator pedal position in response to a corresponding virtual gear selection. An initial virtual gear is determined or selected from a predetermined finite number of available virtual gears based on an accelerator pedal position, a vehicle speed, and whether an upshift or downshift has been requested. The engine speed and engine torque are controlled to meet driver expectations of increased or decreased engine speed or vehicle output torque.

Abstract: A vehicle includes a step-ratio automatic transmission having clutches engageable to provide forward and reverse gears, an electric machine selectively coupled to the transmission, a main pump powered by the electric machine and supplying oil to actuate selected transmission clutches, a gear selector configured for selecting a transmission gear, and a controller configured to stop the electric machine when the gear selector selects park or neutral, to operate the electric machine in a speed control mode using a higher controller gain in response to the gear selector selecting forward or reverse while the electric machine is stopped until the electric machine and the main pump reach a first speed threshold to reduce engagement delay of at least one of the transmission clutches, and to operate the electric machine using a lower controller gain when the electric machine and the main pump exceed the first speed threshold.

Abstract: Systems and methods for operating a hybrid powertrain that includes an engine and a motor/generator are described. The systems and methods align in time an estimated motor torque and an actual motor torque to provide an estimated driveline torque. The alignment compensates for communications delays between different controllers over a controller area network.

Abstract: An autonomous or semi-autonomous vehicle is provided that is capable of braking itself without a driver depressing the brake pedal. The vehicle has a powertrain that includes an engine, a transmission, and a motor with a connected battery to provide regenerative braking capabilities. Friction brakes are provided to apply when necessary, such as when the battery has a high state of charge and further regenerative braking would overcharge the battery. The braking may be activated in response to a sensor detecting a distance to an object in front of the vehicle. A vehicle controller is programmed to automatically control amounts of regenerative braking and friction braking during a braking event based on a comparison between a regenerative torque limit of the powertrain and a desired brake torque over the brake event to safely brake the vehicle during the brake event.

Abstract: A vehicle includes an engine having a crankshaft, a transmission having an input, and a torque converter mechanically coupled to the input. The vehicle further includes an electric machine mechanically coupled to the torque converter, a clutch configured to mechanically couple the electric machine and crankshaft, and one or more controllers. The one or more controllers are programmed to, in response to the transmission being in a drive or reverse gear and a speed of the vehicle being less than a predetermined value in an absence of driver demand, control the electric machine to achieve a target speed to cause the torque converter to output torque such that the speed of the vehicle approaches a generally constant speed less than or equal to the predetermined value when the vehicle is on a generally flat grade.

Abstract: A vehicle includes a powertrain and a controller. The powertrain includes a transmission mechanically coupled to an electric machine and configured to transfer torque between a wheel and the electric machine. The transmission has a gearbox configured to establish gear ratios through a shift. The controller is programmed to, in response to an indication of an expected regenerative braking event having a timing falling within a shift window of the transmission, prevent a clutch of the transmission from disengaging until first occurrence of application of an accelerator pedal or removal of the indication to inhibit the shift prompted by a shift schedule of the gearbox.

Abstract: Methods and systems are provided for operating a hybrid vehicle during operating conditions where vehicle braking is requested. In one example, regenerative braking is allocated to vehicle axles responsive to wheel torques of respective vehicle axles in response to an anti-lock braking system being activated. Additionally, friction braking torque is allocated to vehicle axles responsive to the anti-lock braking system being activated.