A method (200) for the open-loop control of a gearbox (100) that includes a first and a second proportionally controllable shift element (A-F) is provided. The method includes disengaging (215) the first shift element (A-F) according to a first control profile and engaging (220) the second shift element (A-F) of the gearbox (100) according to a second control profile. The first control profile includes a first variable portion which is determined as a function of a temperature of the gearbox (100).

A rotational system can include a shaft assembly rotationally coupling a first rotor, a second rotor, and a fluid pump. A fluid circuit can include the fluid pump that can be configured to motivate a working fluid through the fluid circuit. A pressurizing valve can be disposed downstream of the fluid pump wherein the rotational system can be configured to rotationally decouple the first rotor from the second rotor by closing the pressurizing valve. The pressurizing valve can be actuated by a controller. A method can include raising a pressure differential across a fluid pump driven by a shaft assembly thereby applying an increased braking torque to the shaft assembly. The pressure differential can be raised by actuating a valve in hydraulic communication with the fluid pump. The shaft assembly can rotationally couple a first rotor with a second rotor, and increasing the braking torque can decouple the rotors.

Power transmission systems including clutch arrangement and control systems are adapted to be used in numerous different operational environments. Such power transmission systems may include clutch arrangements that provide more effective power transmission capabilities as well as greater durability and longer life. Control arrangements are provided to more effectively control and monitor clutch operation in ways that provide for greater system flexibility and drive options.

A system for determining a torque converter clutch is stuck in an engaged position includes a control module, an engine speed sensor, and a transmission speed sensor. The control module evaluates the torque converter clutch by determining a value of a torque converter clutch command. The torque converter clutch command indicates a position of the torque converter clutch. In response to determining that the value of the torque converter clutch command indicates the disengaged position, the control module calculates accumulated slip based on the transmission speed and the engine speed during an evaluation time. In response to determining the evaluation time is complete, the control module compares the accumulated slip with a calibrated threshold of slip. In response to the accumulated slip being less than or equal to the calibrated threshold of slip, the control module determines the torque converter clutch is stuck in the engaged position.

A control device of an automatic transmission controls an automatic transmission 1 comprising a transmission mechanism 3 including a plurality of engagement elements, and a hydraulic oil supply device 4 supplying hydraulic oil to the transmission mechanism The control device of the automatic transmission comprises an engagement element control part 41 configured to use the hydraulic oil supply device to make the plurality of engagement elements change between an engaged state and a disengaged state; and a deceleration degree calculating part 42 configured to calculate a target deceleration degree of a vehicle in which the automatic transmission is provided. The engagement element control part is configured to make the engagement element in the disengaged state engage so that the vehicle decelerates if the target deceleration degree is equal to or more than a predetermined value when an increase in temperature of hydraulic oil in the automatic transmission is demanded.

A rotational system can include a shaft assembly rotationally coupling a first rotor, a second rotor, and a fluid pump. A fluid circuit can include the fluid pump that can be configured to motivate a working fluid through the fluid circuit. A pressurizing valve can be disposed downstream of the fluid pump wherein the rotational system can be configured to rotationally decouple the first rotor from the second rotor by closing the pressurizing valve. The pressurizing valve can be actuated by a controller. A method can include raising a pressure differential across a fluid pump driven by a shaft assembly thereby applying an increased braking torque to the shaft assembly. The pressure differential can be raised by actuating a valve in hydraulic communication with the fluid pump. The shaft assembly can rotationally couple a first rotor with a second rotor, and increasing the braking torque can decouple the rotors.

A basic clutch capacity calculating unit calculates a clutch capacity of the DCT applying an engine speed, a degree of throttle opening, and a front wheel vehicle speed to a map. The basic clutch capacity calculating unit further calculates the DCT basic clutch capacity by amending the basic clutch capacity based on an oil temperature and a water temperature. An NE converted value calculating unit calculates an NE converted value obtained by converting a vehicle speed into an engine speed with the front wheel vehicle speed and a DCT speed change stage as input parameters. A hunting detecting unit detects hunting by comparing the engine speed with the NE converted value when a throttle operation is detected. A DCT clutch capacity correcting unit makes decreasing correction of a DCT clutch capacity when hunting is detected for suppressing the hunting.

Related are a method and an apparatus for protecting a clutch in a vehicle driving process. The method comprises: acquiring a current oil temperature of a space where the clutch is located and judging whether the current oil temperature is within a set temperature interval or not; in a case where the current oil temperature is within the set temperature interval, detecting whether a current wheel speed difference between front shaft and rear shaft reaches to a set wheel speed difference threshold or not; and in a case where the current wheel speed difference between the front shaft and rear shaft reaches to the set wheel speed difference threshold, triggering a first protective mode that is preset to protect the clutch; and in a case where the current oil temperature is higher than the set temperature interval, triggering, a second protective mode that is preset to protect the clutch.

A method of, and a system for, controlling and predicting the health of a torque converter clutch control system is provided. The method includes determining, via a controller, rotational input and output speeds of the torque converter and a torque converter clutch slip. The method also includes determining, via the controller, whether a set of predetermined conditions are met for predicting the health of the torque converter clutch control system. The method includes gathering a plurality of initial features of the vehicle propulsion system, determining statistical information about the plurality of initial features, and selecting at least one feature of the vehicle propulsion system based on the statistical information. Furthermore, the method includes classifying the health of the torque converter clutch control system based on the selected feature or features. In some forms, principal component analysis is used to select the feature or features used for classification.

A control device controls a driving force transmission device that presses a main clutch using an actuator that generates a pressing force according to a supply current. The control device includes a current command value setting unit that sets a current command value based on I-T characteristic information indicating the relationship between a current supplied to the actuator and a driving force transmitted, a correction duration setting unit that sets a correction duration based on a responsiveness related value related to the responsiveness of the main clutch when an increase in the driving force to be transmitted by the main clutch becomes greater than or equal to a threshold, a correction unit that increases and corrects the current command value for the set correction duration, and the current control unit that performs current feedback control such that a current corresponding to the current command value is supplied to the actuator.