A method for controlling a vehicle including a continuously variable transmission includes determining, by a controller, whether a speed difference between a speed of a vehicle according to revolutions per minute (RPM) of a driving wheel of the vehicle and a speed of the vehicle according to revolutions per minute (RPM) of a towed wheel of the vehicle is equal to or greater than a speed reference value and reducing, by the controller, torque of an engine providing a driving force to a driving pulley of the continuously variable transmission when the difference in vehicle speed is equal to or greater than the speed reference value.

It is determined whether fuel efficiency of a vehicle is improved by operating a first rotating machine to generate electricity to such an extent that an electrical path amount becomes a desired electrical path amount for controlling an operating point of an engine to a desired operating point and driving and operating a second rotating machine as a second power source, the electrical path amount being a magnitude of electric power in an electrical path through which the electric power is transferred between the first rotating machine and the second rotating machine. When the electronic control device determines that the fuel efficiency of the vehicle is improved, the first rotating machine is operated to generate electricity to such an extent that the electrical path amount becomes the desired electrical path amount and the second rotating machine is driven and operated as the second power source.

Systems and methods for operating an engine and a torque converter are presented. In one example, slip of a torque converter is adjusted via at least partially closing or opening a torque converter clutch in response to vehicle vibration. The vehicle vibration may be based on road surface conditions and an actual total number of operating cylinders of the engine.

A method for operating a motor vehicle drivetrain having a transmission connected between a drive aggregate and a drive output, a Power Take-Off (PTO) that can be coupled to the drive aggregate on drive aggregate side to take up drive torque from the drive aggregate. In order to determine the torque taken up by the PTO, the transmission is first shifted to interrupt torque to the transmission output. Thereafter, a defined torque is delivered by the drive aggregate, at least with the PTO coupled to the drive aggregate, and, during this at defined time-points, rotational speeds of a shaft driven by the drive aggregate are determined and from this an angular acceleration of the shaft is determined. A first torque of the shaft is determined from the shaft angular acceleration while the PTO is coupled. Based on the first torque, the torque taken up by the PTO is determined.

A braking force controller includes: a target jerk calculation unit; a first estimation unit configured to estimate an increment of braking force when a prescribed factor that increases braking force to be generated by the first actuator unit currently occurs; a second estimation unit configured to estimate the increment of the braking force when the prescribed factor occurs within a prescribed period; and a control unit configured to determine a negative jerk generated when the second actuator unit generates the braking force such that a sum of the negative jerk and the jerk generated by the first actuator unit without the prescribed factor becomes the target jerk. When the increment of the braking force due to the prescribed factor is larger than a prescribed value, the control unit corrects the determined negative jerk such that an absolute value of the negative jerk becomes smaller.

A vehicle, a vehicle powertrain system, a computer program product, and a method of controlling a vehicle in a manner to achieve enhanced driving performance. An example vehicle powertrain system includes one or more of a powertrain having an engine, a transmission, and a torque converter, and a control module to control the powertrain system. The control module is configured to conduct, in response to sensor data in connection with a detected current vehicle speed and a detected current transmission oil temperature, a vehicle powertrain analysis of the sensor data. The control module is to then control the powertrain in response to the vehicle powertrain analysis and an operating state of a lock-up clutch of the torque converter.

A method and system for operating a vehicle that includes an automatic transmission with a torque converter clutch is described. In one example, the method includes predicting a time that the torque converter clutch will open so that stopping rotation of the engine may be requested before the torque converter clutch is opened. The stopping rotation of the engine is requested to conserve fuel.

Systems and methods for improving operation of a vehicle are presented. In one example, a controller may respond to a temperature of a catalyst to permit or temporarily inhibit a vehicle from moving. Engine load and engine emissions may be reduced by limiting vehicle motion until a catalyst temperature exceeds a threshold temperature.

Methods and systems for operating a torque converter clutch of an automatic transmission are presented. In one non-limiting example, the torque converter clutch is closed to provide a threshold torque capacity during a vehicle launch. If an engine torque request is less than the threshold torque capacity, the torque converter clutch remains closed.

Systems and methods for operating a hybrid powertrain that includes an engine and a motor/generator are described. The systems and methods adjust torque converter clutch opening responsive to whether or not a motor/generator is available to provide a negative torque to a driveline. Further, the motor/generator and the vehicle's engine are operated to provide a desired amount of driveline braking.