Disclosed is a clutch control reference value setting method including generating a current-hydraulic pressure model, setting a temporary VKP to a current causing a maximum difference between a model hydraulic pressure and a measured hydraulic pressure, determining that the temporary VKP is valid when a deflection amount calculated from a difference integral value acquired by integrating differences between the model hydraulic pressure and the measured hydraulic pressure while increasing the current is greater than a first reference value under a condition that the first target pressure is applied to the clutch, determining that the temporary VKP is appropriate when a deflection amount calculated from a difference integral value acquired by integrating differences between the model hydraulic pressure and the measured hydraulic pressure while increasing the current is proper under a condition that a second target pressure is applied to the clutch.

A clutch device has at least a multiplicity of clutch discs which are in frictional contact with one another, and a control unit which controls the clutch device. The clutch device is calibrated repeatedly during an operating time of the clutch device. A first calibration is performed at a first point in time. A second calibration is performed at a second point following the first calibration. The first point in time and the second point in time are within a first operating time of the clutch device and occur within a first time interval. At least a third calibration is performed in a subsequent second operating time at a third point in time. At least the second calibration is performed within a second interval of the third point in time. The first and second intervals are determined by the control unit based on a mileage of a vehicle or an energy input into the clutch device. The first interval is shorter than the second interval.

A method for determining a kiss point. A drive unit having one or more motors with a motor output shaft is provided. One or more actuation profiles are ran and an amount of motor current and motor shaft position data is measured. The data measured is filtered and one or more motor current vs. motor shaft position plots having one or more curves with a high force and high current region are generated. A derivative is calculated over the curves and a slope of the high force and high current region is determined. A relative slope threshold is determined by multiplying the slopes by a predetermined percentage. One or more lines having a slope substantially equal to the relative slope threshold are plotted. The kiss point is determined based on the position of the motor shaft where the derivative of the curves equals the slope of the lines plotted.

A method for determining a kiss point. A drive unit having one or more motors with a motor output shaft is provided. One or more actuation profiles are ran and an amount of motor current and motor shaft position data is measured. The data measured is filtered and one or more motor current vs. motor shaft position plots having one or more curves with a high force and high current region are generated. A derivative is calculated over the curves and a slope of the high force and high current region is determined. A relative slope threshold is determined by multiplying the slopes by a predetermined percentage. One or more lines having a slope substantially equal to the relative slope threshold are plotted. The kiss point is determined based on the position of the motor shaft where the derivative of the curves equals the slope of the lines plotted.

Provided is a lock-up clutch control device of a vehicle in which a torque converter with a lock-up clutch is disposed between an engine and a transmission. This control device has a coasting capacity learning control section configured to decrease a LU differential pressure command value for the lock-up clutch during accelerator release operation and, when a slip of the lock-up clutch is detected during decrease of the LU differential pressure command value, update the LU differential pressure command value at the time of detection of the slip as a LU differential pressure learning value balanced with a coasting torque. The coasting capacity learning control section is further configured to, when operation of the PTC heater intervenes during coasting capacity learning control, correct the LU differential pressure command value by adding thereto a LU differential pressure correction value that corresponds to an increase of input torque to the lock-up clutch.

A clutch control method may include generating a current-hydraulic pressure model by obtaining an increasing slope of a measured hydraulic pressure which is applied to a clutch in accordance with an increase of a primary ramp current while applying the primary ramp current to a solenoid valve that controls hydraulic pressure to be supplied to the clutch; obtaining a difference between a virtual hydraulic pressure according to the current-hydraulic pressure model and a measured hydraulic pressure applied to the clutch for a secondary ramp current while applying the secondary ramp current to the solenoid valve after removing the primary ramp current; performing updating by learning a secondary ramp current, at which the difference between the virtual hydraulic pressure and the measured hydraulic pressure is maximum, as a Volumetric Kiss Point (VKP); and controlling the clutch on the basis of the learned VKP.

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 vehicle control device includes: a unit that acquires a first transmission torque transmitted in a first state in which a control pressure is controlled to a first pressure value, and a second transmission torque transmitted in a second state in which the control pressure is controlled to a second pressure value; a control unit including a storage unit that stores control data including data indicating a relationship between a friction coefficient and a surface pressure. The control unit calculates a first friction coefficient based on the data and the first pressure value, calculates a second friction coefficient based on the data and the second pressure value, calculates an estimated value of the touch point pressure based on the first and second pressure values, the first and second transmission torques, the first and second friction coefficients to control data based on the estimated value.

Provided is a method of learning a touch point of a dual clutch transmission (DCT), and more particularly, to a DCT touch point learning method in which a touch point is learned based on a difference between a virtual input shaft speed and a clutch non-drive shaft input speed using a virtual input shaft reference speed calculated based on the speed of a traveling vehicle. In a traveling situation in which the touch point cannot be learned using the non-drive shaft according to the related art because the input shaft behavior of the non-drive shaft is rotationally synchronized with the input shaft behavior of the drive shaft by drag characteristics of the DCT, a virtual input shaft speed may be calculated, and the touch point of the clutch may be learned using the virtual input shaft speed.

A clutch control method may include generating a current-hydraulic pressure model by obtaining an increasing slope of a measured hydraulic pressure which is applied to a clutch in accordance with an increase of a primary ramp current while applying the primary ramp current to a solenoid valve that controls hydraulic pressure to be supplied to the clutch; obtaining a difference between a virtual hydraulic pressure according to the current-hydraulic pressure model and a measured hydraulic pressure applied to the clutch for a secondary ramp current while applying the secondary ramp current to the solenoid valve after removing the primary ramp current; performing updating by learning a secondary ramp current, at which the difference between the virtual hydraulic pressure and the measured hydraulic pressure is maximum, as a Volumetric Kiss Point (VKP); and controlling the clutch on the basis of the learned VKP.