The invention relates to a method for determining a bite point of a hybrid clutch in a hybrid vehicle. The hybrid clutch is actuated by a hydrostatic clutch actuator (12) and disconnects or connects an internal combustion engine (2) and an electric motor (3); the bite point is determined by slowly actuating the hybrid clutch (4) starting from a separating position of the hybrid clutch (4), this position being in the non-actuated state, with a defined torque reaction of the electric motor (3) being detected. The invention also relates to a method in which the quality of the bite point is improved, the duration of the bite point adaptation is essentially shortened, the bite point being adapted during the running of the internal combustion engine (2) and when the electric motor (3) is immobile and a torque reaction of the electric motor (3) is validated by the torque reaction of the internal combustion engine (2).

Disclosed are a method and an apparatus for detecting a touch point of a clutch and the method includes: maintaining a touch point of the clutch; correcting a setting value for determining a lowest value by calculating drag torque using a speed and an acceleration of a input shaft to change a detection range of the touch point; setting the lowest value of the speed of the input shaft within the changed detection range of the touch point to a reference value of the input shaft after actuating the clutch; releasing the clutch when the speed of the input shaft is more than a value acquired by adding the reference value of the input shaft and the corrected setting value for determining the lowest value; and updating the touch point as a clutch position matched to the reference value.

A method for learning a touch point of a clutch may include a step of outputting a first control signal for controlling a touch point learning mode to be entered if a preset condition is satisfied, a step of calculating a reference value by dividing a difference value between rotational speed of a drive shaft clutch and rotational speed of a non-drive shaft clutch by a difference value between rotational speed of an engine and the rotational speed of the drive shaft clutch, a step of outputting a second control signal for moving the non-drive shaft clutch toward the engine if the reference value is less than a preset threshold value and a step of determining a position of the non-drive shaft clutch at a time when the reference value reaches the preset threshold value to be the touch point.

A method for learning a torque-stroke (T-S) curve of an electric motor controlled dry clutch system is disclosed. The method includes calculating a position change value A for allowing a position change point P3 corresponding to an arbitrary torque y3 on a previous T-S curve C1 to follow-up and be moved to an expectation T-S curve C3, by a control unit, calculating a probability Pr_X3 to allow the position change value A to consider various environmental factors of a clutch within a valid range, and multiplying the probability Pr_X3 to the position change value A to calculate a final position change value A, by the control unit, and calculating a new point P3 by applying the final position change value A to the position change point P3 of the previous T-S curve C1, and generating a final T-S curve connecting the new point P3 and a touch point to learn, by the control unit.

The invention relates to a method for determining a characteristic curve of a clutch of a clutch activation system in a drivetrain, in particular of a motor vehicle, in which the clutch is activated by an actuator, wherein a bite point of the clutch is adapted as a first support point of the characteristic curve. In a method in which the accuracy of the specific clutch characteristic curve is improved, a preload point of the actuator, preferably of an electric central disengagement device, is used as a second support point of the characteristic curve.

A method for automatic detection of need for clutch calibration includes registering and storing in a data memory, before or in connection with engine shut down, a value of a clutch operating parameter, registering a corresponding value of the clutch operating parameter in connection with subsequent engine start up, and determining need for clutch calibration if the difference between the stored value of the clutch operating parameter and the corresponding value of the clutch operating parameter exceeds a predetermined threshold value.

A method of controlling an all-wheel-drive system connect event including providing a power transmission apparatus having a clutch, a propeller shaft, and a rear drive unit with a clutch pack assembly. The rear drive unit clutch pack is actuated by creating a model of the propeller shaft rotational speed, adapting the model parameters to compensate for temperature and vehicle wheel speed, storing the model, adapting the model utilizing information collected during a previous all-wheel-drive system connect event, and developing a set point for the clutch driving element utilizing the model and a multi-loop control architecture. The power transmission apparatus clutch is then engaged.

A method for learning a contact point of an engine clutch configured to control connection of power between an engine and a motor of a hybrid vehicle is provided. The method includes performing a first learning of the contact point of the engine clutch by increasing a contact speed of the engine clutch and storing information of a first contact point learned by the first learning. A second learning of the contact point of the engine clutch is then performed by decreasing the contact speed of the engine clutch.

Provided are a method and an apparatus for learning a touch point of a clutch. The method of learning the touch point of the clutch comprises a step of outputting a first control signal for controlling a touch point learning mode to be entered if a preset condition is satisfied, a step of calculating a reference value by dividing a difference value between driving speed of a drive shaft clutch and driving speed of a non-drive shaft clutch by a difference value between driving speed of an engine and the driving speed of the drive shaft clutch, a step of outputting a second control signal for moving the non-drive shaft clutch toward the engine if the reference value is less than a preset threshold value and a step of determining a position of the non-drive shaft clutch at a time when the reference value reaches the preset threshold value to be the touch point.

A method for learning a torque-stroke (T-S) curve of an electric motor controlled dry clutch system is disclosed. The method includes calculating a position change value A for allowing a position change point P3 corresponding to an arbitrary torque y3 on a previous T-S curve C1 to follow-up and be moved to an expectation T-S curve C3, by a control unit, calculating a probability Pr_X3 to allow the position change value A to consider various environmental factors of a clutch within a valid range, and multiplying the probability Pr_X3 to the position change value A to calculate a final position change value A, by the control unit, and calculating a new point P3 by applying the final position change value A to the position change point P3 of the previous T-S curve C1, and generating a final T-S curve connecting the new point P3 and a touch point to learn, by the control unit.