Abstract: A hybrid electric vehicle has a traction motor, a driveline connected to a vehicle wheel, and a controller. The controller is configured to control motor torque through a region surrounding vehicle wheel torque reversal, control driveline input torque during torque reversal of driveline output torque to limit rate of change of driveline output torque, and control motor torque during a torque reversal of at least one driveline component to limit rate of change of the torque applied to the driveline component. A method for controlling a vehicle having a traction motor includes controlling the traction motor torque through a region surrounding a vehicle wheel torque reversal, controlling driveline input torque during torque reversal of driveline output torque to limit rate of change of output torque, and controlling traction motor torque during a torque reversal of a powertrain component to limit rate of change of the torque applied to the component.

Abstract: A method and a system for reducing driveline speed oscillations related to a driveline resonance frequency are described. Driveline speed oscillations may be reduced via slipping a driveline clutch or adjusting torque of a driveline motor/generator. The method and system may be activated during select vehicle operating conditions.

Abstract: A method of controlling a hybrid vehicle having a step ratio transmission is disclosed. The method utilizes terrain data to reduce the number of shift events. The method comprises receiving data indicative of a grade profile of an anticipated route, identifying a forecast shift sequence comprising a forecast downshift event and an adjacent forecast upshift event, and adjusting the shift criteria based on the time between the forecast shift events, the road grade between the forecast shift events, and the state of a storage battery.

Abstract: A vehicle includes a power source, such as an engine, an electric machine, or combination thereof. A torque converter is selectively coupled to the power source such that torque is altered before being distributed into a transmission of the vehicle. A torque converter bypass clutch enables torque from the power source to selectively transmit torque directly to the transmission with little or no torque altering provided by the torque converter. At least one controller in the vehicle is in communication with a remote facility in a vehicle-to-cloud (V2C) system. The controller sends road condition data to the remote facility regarding a road segment. During a subsequent drive to or over the road segment, the controller receives the road condition data and enables the torque converter bypass clutch to slip to dampen driveline disturbances when the vehicle passes over the road segment.

Abstract: A system and method for automatically angularly positioning wheels of an automotive vehicle after parking. The system disclosed here includes a power-assisted steering system coupled to the wheels. Further, the system includes a controller, coupled to the steering system, which is configured to automatically position the wheels in a desired direction, based on a determination that the vehicle is parked.

Abstract: A method for controlling a downstream clutch in a vehicle during an upstream torque disturbance includes slipping a downstream clutch by reducing the downstream clutch pressure, varying the downstream clutch pressure to a target threshold to control the slip of the downstream clutch, increasing the downstream clutch pressure to engage the downstream clutch. A vehicle includes a first prime mover, a second prime mover connected to the first prime mover using an upstream clutch, a transmission connected to the second prime mover using a downstream clutch, and a controller connected to the first and second prime movers and the upstream and downstream clutches. The controller is configured to (i) slip the downstream clutch by reducing the pressure, (ii) vary the downstream clutch pressure to a target threshold to control the slip, and (iii) increase the downstream clutch pressure to engage the clutch.

Abstract: A vehicle includes an engine, a traction motor, and a torque converter that is driven by the traction motor. A clutch arrangement mechanically couples an output of the torque converter to transmission gearing. A controller is provided in the vehicle that is configured to command an increase in slip, or decrease in clutch pressure, in the clutch arrangement in response to an increase in speed of the traction motor. The commanding of an increase in slip enables a product of the torque ratio of the torque converter and an input torque to the torque converter to remain generally constant during the increase in speed of the traction motor.

Abstract: A system and method for controlling a hybrid electric vehicle during regenerative braking is provided. The system and method include a brake controller adapted to cause, for a selected transmission gear, a first torque ratio to be applied to a regenerative brake system during regenerative braking and a second torque ratio, different from the first torque ratio, to be applied when the vehicle is not regenerative braking. The first torque ratio results in an increased braking torque generated by the regenerative brake system compared with application of the second torque ratio.

Abstract: A system and method for controlling a hybrid electric vehicle during regenerative braking is provided. The system and method include a brake controller adapted to cause, for a selected transmission gear, a first torque ratio to be applied to a regenerative brake system during regenerative braking and a second torque ratio, different from the first torque ratio, to be applied when the vehicle is not regenerative braking. The first torque ratio results in an increased braking torque generated by the regenerative brake system compared with application of the second torque ratio.

Abstract: A system and method for controlling a vehicle having an electric traction motor coupled to a transmission by a clutch include modifying traction motor torque in response to the difference between rotational speed of a driveline component and the filtered rotational speed of the driveline component to reduce driveline oscillation when the clutch is locked. The traction motor torque may be modified in response to a vehicle event that may otherwise induce driveline oscillations, such as a transmission ratio change or regenerative braking, for example.

Abstract: A hybrid electric vehicle includes an engine and a traction motor coupled to the engine by a coupling device or a clutch for providing torque to wheels of the vehicle. An inverter is electrically connected to the traction motor. A second coupling device or at least one clutch at least indirectly selectively couples the motor to the drive wheels. A controller controls the second coupling device based upon a temperature of at least one of the fraction motor and the inverter.

Abstract: A vehicle includes an engine, a traction motor, and a torque converter that is driven by the traction motor. A clutch arrangement mechanically couples an output of the torque converter to transmission gearing. A controller is provided in the vehicle that is configured to command an increase in slip, or decrease in clutch pressure, in the clutch arrangement in response to an increase in speed of the traction motor. The commanding of an increase in slip enables a product of the torque ratio of the torque converter and an input torque to the torque converter to remain generally constant during the increase in speed of the traction motor.

Abstract: A controller and control strategies minimize shift shock in a hybrid electric vehicle during a downshift during regenerative braking by maintaining the transmission input speed substantially linear when the transmission input speed is slowing. The controller and the control strategies control the regenerative braking torque during a downshift occurring during regenerative braking in such a way that the transmission input speed is maintained substantially linear when the transmission input speed is slowing during a torque phase of the downshift.

Abstract: A vehicle includes an engine and is at least partially propelled by a fraction battery and a traction motor. A clutch is configured to be coupled to the traction motor. An electrical and/or mechanical pump provides pressure to control the clutch. At least one controller determines if the clutch is slipping. In response to the clutch slipping, the at least one controller commands an increase in speed of an input of the clutch such that the available line pressure to control the slipping of the clutch is increased. The line pressure is then applied to the clutch in order to control the slipping of the clutch.

Abstract: A method of controlling a hybrid vehicle having a step ratio transmission is disclosed. The method utilizes terrain data to reduce the number of shift events. The method comprises receiving data indicative of a grade profile of an anticipated route, identifying a forecast shift sequence comprising a forecast downshift event and an adjacent forecast upshift event, and adjusting the shift criteria based on the time between the forecast shift events, the road grade between the forecast shift events, and the state of a storage battery.

Abstract: A system and method for controlling a vehicle having an electric traction motor coupled to a transmission by a clutch include modifying torque transmitted to the driveline by modifying the clutch apply pressure in response to a difference between rotational speed of a driveline component and a filtered rotational speed of the driveline component to reduce driveline oscillation when the clutch is unlocked. The clutch pressure may be modified in response to a vehicle event that may otherwise induce driveline oscillations, such as a transmission ratio change or regenerative braking, for example.

Abstract: A vehicle has an engine, an upstream clutch, an electric machine, a downstream clutch, a transmission gearbox, and a controller. The controller is configured to: (i) control engagement of the downstream clutch, (ii) monitor a vehicle torque, and (iii) control electric machine torque to a designated rate when the vehicle torque changes direction and the electric machine is operating. A method for controlling a hybrid vehicle includes engaging a clutch downstream of the electric machine, monitoring a vehicle torque, and controlling electric machine torque to a designated rate when vehicle torque changes direction and the electric machine is operating. A hybrid vehicle system has an electric machine and a controller configured to (i) control electric machine torque to a designated rate within a time zone, and (ii) control at least one of the electric machine torque and an engine torque to meet driver demand outside of the zone.

Abstract: A method for controlling an electric vehicle having a traction motor connected to a driveline includes controlling traction motor output torque through a region surrounding the vehicle wheel torque reversal to mitigate torque disturbances in a driveline, wherein the region is determined using a relationship between driveline input torque and driveline output torque and is bounded by a zero input torque and a zero output torque. A hybrid electric vehicle has a traction motor, a driveline connected to a vehicle wheel, and a controller configured to control traction motor output torque through a region surrounding a vehicle wheel torque reversal to mitigate torque disturbances in the driveline. A control system for a hybrid vehicle includes a traction motor and a controller. The controller is configured to control traction motor output torque through a region surrounding a vehicle wheel torque reversal to mitigate torque disturbances in the driveline.

Abstract: A hybrid electric vehicle has a traction motor, a driveline connected to a vehicle wheel, and a controller. The controller is configured to control motor torque through a region surrounding vehicle wheel torque reversal, control driveline input torque during torque reversal of driveline output torque to limit rate of change of driveline output torque, and control motor torque during a torque reversal of at least one driveline component to limit rate of change of the torque applied to the driveline component. A method for controlling a vehicle having a traction motor includes controlling the traction motor torque through a region surrounding a vehicle wheel torque reversal, controlling driveline input torque during torque reversal of driveline output torque to limit rate of change of output torque, and controlling traction motor torque during a torque reversal of a powertrain component to limit rate of change of the torque applied to the component.

Abstract: A vehicle includes a motor/generator, a starter motor, a disconnect clutch disposed between the engine and the motor/generator, and at least one clutch disposed between the motor/generator and the vehicle drive wheels. When an engine start is requested, various parameters are controlled to ensure a smooth engine start wherein driveline torque disturbances are minimized. The starter motor is used to crank the engine upon an engine start request, thereby eliminating the need to transfer torque from the motor/generator to the engine. This helps to further reduce torque disturbances in the driveline when the engine is started.