The present invention comprises: a synchronization start determination unit 110 for determining a synchronization start of a synchronization device 70; a half-clutch determination unit 130 for determining whether a clutch device 20 is in a half-clutch state where the clutch device has not been switched from a connection state to a disconnection state; and a damage determination unit 140 which, when the synchronization start determination unit 110 has determined the synchronization start and if the half-cutch determination unit 130 has determined a half-clutch state, determines that damage is applied to the synchronization device 70 caused by the differential rotation between the power transmitted from a driving force source 10 side via the clutch device 20 and the power transmitted from a driving wheels 16L, 16R side.

The present disclosure relates to a method for defining a clutch slipping point position (X.sub.sp) of a clutch in a gearbox comprising an input shaft arranged to be braked by a braking means. The method includes determining if the clutch is dragging when the clutch is fully disengaged. The method includes when it is determined that the clutch is dragging, applying the braking means with a predetermined brake torque (T.sub.b) and so that the input shaft is not rotating; and thereafter: moving the clutch from the fully disengaged position towards an engaged position; determining when the input shaft starts to rotate with a predetermined rotation value indicative of a rotational speed of the input shaft; registering a clutch position (X.sub.b) in which the clutch is positioned when the predetermined rotation value is reached; using a clutch transfer characteristics of the clutch, T.sub.b, and X.sub.b to define the clutch slipping point position (X.sub.sp).

A hydrostatic actuator system includes an electric motor for delivering a hydraulic fluid via a piston unit. The actuator system is operating using a method in which a change in volume caused by a temperature change is sensed by a pressure measurement. The method reliably identifies a state of the transfer of the hydraulic fluid from a planetary roller transmission compartment into the master piston. The pressure measurement is continuously evaluated, and, in the event of a negative signal of the pressure measurement, suction of the hydraulic fluid by a planetary roller transmission lying in the hydraulic fluid between the electric motor and the piston unit into the piston unit is recognized and a fault signal is output.

A method for automatically warming up a clutch actuator for a clutch of a transmission in a vehicle, wherein the clutch actuator is operable by use of pressurized fluid and configured to actuate the clutch from an engaged to a disengaged state, and/or vice versa, the method including: identifying if a temperature is below a predetermined temperature value and if the clutch actuator is leaking, and if it is identified that the temperature is below the predetermined temperature value and that the clutch actuator is leaking; then repeatedly pressurizing the clutch actuator by use of the pressurized fluid until a state is reached indicative of the clutch actuator being functional, or until a maximum run out state is reached indicative of a faulty clutch actuator.

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.

Methods and systems for a transmission are provided. The method includes estimating a stroke position of the hydraulic control piston based on a pressure of a fluid in a hydraulic line and a valve and a coefficient of the hydraulic line, where the hydraulic line is coupled to a chamber of the hydraulic control piston. The method further includes controlling a pressure of fluid delivered from the valve to the hydraulic control piston based on the estimated stroke position to achieve a piston stroke set-point during a filling phase.

A sensorless clutch state feedback method is provided including a driveline disconnect. To engage the sensorless disconnect, respective speeds of a motor assembly and the sensorless disconnect are synchronized to within a speed delta threshold of each other, a control system facilitates the engagement of the motor assembly and the sensorless disconnect, and the control system determines the success of the engagement by the motor speed response of the motor assembly (e.g., whether the presence of a load is detected).

A vehicle drive device (1) is disclosed that includes a shift detent mechanism (90); an actuator (74) that generates drive power for allowing the shift detent mechanism to operate; a sensor (135) that generates sensor information indicating an amount of operation of the shift detent mechanism; a control part (153) that controls the actuator; and a clutch (30) that is synchronized with operation of the shift detent mechanism, and when the control part changes a state of the clutch, the control part performs feedback control of the actuator based on a relationship between a target value for an amount of operation of the shift detent mechanism and the sensor information, and before completing the change in the state of the clutch, the feedback control ends and operation of the actuator stops.

A method to estimate an amount of force in a clutch pack of a clutch actuation system. The method includes engaging an actuation motor to apply a set point force to the clutch pack and monitoring a position of the actuation motor when the set point force is applied. Additionally, the method includes determining one or more clutch clamping curves and one or more clutch releasing curves based on a relationship between the position of the actuation motor and an amount of torque applied by the actuation motor at position of the actuation motor. The method further includes modeling one or more frictional characteristics of the clutch actuation system and estimating an amount of clamping and releasing force within the clutch pack by using a control unit. The amount of torque applied to the clutch pack between the clutch clamping and releasing curves at the set point force is maintained.

This clutch control device includes an engine (13), a transmission (21), a clutch device (26) configured to connect and disconnect motive power transmission between the engine (13) and the transmission (21), a clutch actuator (50) configured to drive the clutch device (26) and change a clutch capacity, a control parameter sensor (58) configured to detect a control parameter of the clutch capacity and a control unit (60) configured to calculate a control target value (TP) of the control parameter. The control unit (60) causes the clutch device (26) to perform a stroke in a connection direction until an actual measurement value of the control parameter reaches the control target value (TP). The control unit (60) corrects the control target value (TP) in accordance with at least one of a rotational speed (NE) of the engine (13) and a difference between the target value and the actual measurement value of the control parameter in a stroke process (K3) of causing the clutch device (26) to perform the stroke in the connection direction.