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 power transmission device includes a friction clutch, an actuator, and a controller configured to determine an approximated temperature change of the friction clutch. The controller is configured to determine a current power state of the friction clutch, determine a desired power state change based on the current power state and a previous power state, determine a plurality of thermal coefficients based on a thermal coefficient model, the desired power state change, and a set of operation variables, determine an approximated temperature change of the friction clutch based on the thermal coefficients and a friction clutch temperature model, determine an approximated clutch temperature based on the approximated temperature change and a contemporaneous value of an device ambient temperature, and control operation of the actuator based at least on the approximated clutch temperature.

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.

A method and system for controlling clutch friction elements of an automatic transmission is provided. The method includes retrieving information about shift clutches from a data storage unit and acquiring information required to predict a temperature of a friction element for each shift clutch, deriving a predicted temperature value of a friction element for each shift clutch by using the information about the shift clutches and the information required to predict the temperature of the friction element, predicting whether or not overheating occurs for each shift clutch by comparing the derived predicted temperature value of the friction element for each shift clutch with an allowable temperature set for each shift clutch, and determining a target shift stage while avoiding the overheating clutch with a predicted temperature value exceeding the allowable temperature, through switching to an avoidance shift mode.

A vehicle control device for controlling a vehicle with a frictional engagement element provided between a drive source and drive wheels includes a first determination unit configured to determine whether or not a signal of an inhibitor switch indicates a traveling position, a second determination unit configured to determine whether or not an oil path communicating with the frictional engagement element is in a drain state, a temperature estimation unit configured to estimate temperature of the frictional engagement element, and a temperature estimation prohibition unit configured to prohibit temperature estimation of the frictional engagement element by the temperature estimation unit when the signal of the inhibitor switch indicates the traveling position and the oil path is in the drain state.

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 (a controller), and systems and methods for management of inputs, determination of a calculated clutch temperature, and control of action related to the clutch of a transmission system, and notification improvements to a user associated therewith are disclosed. In particular, a clutch calculator circuit is augmented by a machine learning component that employs a machine learning technique and provides a projected clutch temperature as a basis for actions to be taken.

A power transmission device includes a friction clutch, an actuator with an output member, and a controller. The friction clutch is lubricated with a lubricant. The controller is configured to determine a current power state of the friction clutch and determine values for a plurality of thermal coefficients based on the current power state, a set of operation variables, and one or more multi-variable correlation data. The controller is further configured to determine an approximated temperature change of the lubricant based on the values of the plurality of thermal coefficients and a lubricant temperature model. The controller is further configured to determine an approximated lubricant temperature based on the approximated temperature change and a device ambient temperature, and to control operation of the actuator based at least on the approximated lubricant temperature.

The disclosure relates to a method for controlling a driveline (10) of a vehicle (1), wherein the driveline (10) at least comprises a transmission (13) and a clutch (12), wherein the clutch (12) is adapted to be provided between the transmission (13) and a propulsion unit (11) of the driveline (10), wherein the method comprises the steps of; predicting an imminent drive route, identifying if the imminent drive route comprises any clutch severity classification (CSC), and if the imminent drive route comprises a clutch severity classification (CSC)—estimating (103) an expected clutch temperature (Tic) dependent on at least the clutch severity classification (CSC) and one vehicle parameter (Vp), wherein, the clutch severity classification (CSC) is at least dependent on an inclination of the imminent drive route, and if (105) the expected clutch temperature (Tic) is above a clutch temperature threshold value (Tt); controlling (106) the driveline (10) in a critical heat mode, wherein in the critical heat mode the transmission (13) is controlled such that a clutch temperature increase is lower in comparison to a normal driveline control mode.

The disclosure relates to a method for controlling a driveline (10) of a vehicle (1), wherein the driveline (10) at least comprises a transmission (13) and a clutch (12), wherein the clutch (12) is adapted to be provided between the transmission (13) and a propulsion unit (11) of the driveline (10), wherein the method comprises the steps of; predicting an imminent drive route, identifying if the imminent drive route comprises any clutch severity classification (CSC), and if the imminent drive route comprises a clutch severity classification (CSC)—estimating (103) an expected clutch temperature (Tic) dependent on at least the clutch severity classification (CSC) and one vehicle parameter (Vp), wherein, the clutch severity classification (CSC) is at least dependent on an inclination of the imminent drive route, and if (105) the expected clutch temperature (Tic) is above a clutch temperature threshold value (Tt); controlling (106) the driveline (10) in a critical heat mode, wherein in the critical heat mode the transmission (13) is controlled such that a clutch temperature increase is lower in comparison to a normal driveline control mode.