A method of setting a clutch control reference value may make it possible to more accurately learn the VKP of a hydraulic multi-plate clutch controlled by a solenoid valve, improving the accuracy of clutch control, and furthermore, to improve the quality of shifting a vehicle by the precise control of a transmission provided with such a clutch.

A method of setting a clutch control reference value may make it possible to more accurately learn the VKP of a hydraulic multi-plate clutch controlled by a solenoid valve, improving the accuracy of clutch control, and furthermore, to improve the quality of shifting a vehicle by the precise control of a transmission provided with such a clutch.

An apparatus to be applied to a vehicle including a transmission configured to execute a gear shifting operation for changing a gear ratio by engaging or disengaging friction engagement elements having friction members pushed by a piston that moves through hydraulic pressure supply to an oil chamber, the apparatus including: a memory storing mapping data for defining mapping, the mapping including a pressure variable and a period variable as input variables, the mapping including a stroke amount as an output variable, the pressure variable indicating a waiting pressure, the period variable indicating a waiting period; and a processor configured to: acquire values of the input variables, and calculate a value of the output variable by inputting, to the mapping, the acquired values of the input variables.

A method for operating an automated drive train of a motor vehicle in which, upon actuation of a service brake up to a standstill of the vehicle, a drive connection between the drive machine and at least one drive axle of the vehicle is automatically disengaged by disengaging a clutch. During release of the service brake, the drive connection is automatically engaged by engaging the clutch. Based on a selected gear step, a desired drive direction of the vehicle is determined, and, during the release of the service brake, is compared with an actual drive direction. If the desired drive direction matches the actual drive direction, the pressure in the clutch is increased according to a first modulation characteristic curve. However, if the desired drive direction is different from the actual drive direction, the pressure in the clutch is increased according to a second modulation characteristic curve.

A method of adjusting and using operating parameters of a transmission of a vehicle may include accessing a stored list of clutch parameters, performing a dynamic condition procedure while the vehicle is driven to revise minimum on-coming apply pressure for each friction element based on a sensed performance of an element within the vehicle powertrain, storing the modified minimum on-coming apply pressures, and operating the vehicle. A related transmission control device operates a transmission using parameters obtained during a dynamic condition procedure.

The disclosure relates to a method for calibrating a drive system for an axle of a motor vehicle; wherein the drive system includes at least one electric machine as the drive unit, a drive shaft driven by the drive unit, a first output shaft and a second output shaft, as well as a first clutch connecting the drive shaft to the first output shaft and a second clutch connecting the drive shaft to the second output shaft.

A method for operating an electrohydraulic transmission clutch of a motor vehicle, wherein, for a clutch operation, a hydraulic pressure is set by way of a regulating device of a controller as a function of a clutch signal, and, through the pressure, a disengagement element of the transmission clutch is moved through a soft region into a rigid region via a rigid point, or vice versa. The soft region is to be compensated for. Further, as a function of the clutch signal, the regulating device generates a preliminary target value signal for the pressure and a time derivative of the preliminary target value signal is generated as a movement signal, and a pilot control generates a pilot control signal as a function of the movement signal, and the preliminary target value signal and the pilot control signal are combined to give a final actuating value signal for the pressure.

A method for controlling an actuator includes providing the actuator with a control unit, a drive unit including an electric motor with a stator and a rotor, a rotor position sensor, connected to the control unit, for detecting a rotation of the rotor, and a displacer unit, drivable by the rotation of the rotor, for displacing a fluid. The displacer unit includes a geometric displacement volume per revolution of the rotor. The method also includes generating a predetermined pressure at the displacer unit by applying an electrical driving power to the electric motor, maintaining the predetermined pressure over a predetermined time interval, determining the rotation of the rotor with the rotor position sensor during the predetermined time interval, and determining a leakage volume flow.

A method for operating an automated drive train of a motor vehicle in which, upon actuation of a service brake up to a standstill of the vehicle, a drive connection between the drive machine and at least one drive axle of the vehicle is automatically disengaged by disengaging a clutch. During release of the service brake, the drive connection is automatically engaged by engaging the clutch. Based on a selected gear step, a desired drive direction of the vehicle is determined, and, during the release of the service brake, is compared with an actual drive direction. If the desired drive direction matches the actual drive direction, the pressure in the clutch is increased according to a first modulation characteristic curve. However, if the desired drive direction is different from the actual drive direction, the pressure in the clutch is increased according to a second modulation characteristic curve.

A hybrid vehicle includes an engine, an electric machine selectively coupled to the engine, a transmission having a torque converter impeller coupled to the electric machine and a torque converter clutch configured to selectively couple the impeller to a turbine, and a controller configured to control pressure of the torque converter clutch responsive to estimated clutch capacity, which is adjusted by the controller to equal impeller torque responsive to impeller speed exceeding turbine speed during clutch disengagement. A model of estimated torque converter clutch capacity may be stored in memory and adapted to actual clutch capacity by applying a gain or offset determined during opening of the clutch.