A method of controlling line pressure of a hydraulic circuit of a transmission, may include turning on electric current by a controller to apply the electric current to an electric oil pump and determining line pressure depending on the electric current applied; and turning off the electric current by the controller so that the electric current being applied to the electric oil pump is cut off when the determined line pressure is greater than a predetermined reference upper limit value, estimating line pressure dropping down with a passage of time and determining the estimated line pressure, wherein when the estimated line pressure becomes lower than a predetermined reference lower limit value, the turning on the electric current is repeated.

A method of controlling line pressure of a hydraulic circuit of a transmission, may include turning on electric current by a controller to apply the electric current to an electric oil pump and determining line pressure depending on the electric current applied; and turning off the electric current by the controller so that the electric current being applied to the electric oil pump is cut off when the determined line pressure is greater than a predetermined reference upper limit value, estimating line pressure dropping down with a passage of time and determining the estimated line pressure, wherein when the estimated line pressure becomes lower than a predetermined reference lower limit value, the turning on the electric current is repeated.

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.

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.

An electric vehicle drive apparatus includes a first motor, a second motor, a speed change mechanism coupled to the first motor and the second motor, and a controller controlling operation of the first motor and the second motor. The speed change mechanism includes a first planetary gear mechanism, a second planetary gear mechanism, and a one-way clutch that limits a rotation direction of a first carrier of the first planetary gear mechanism to a certain forward rotation direction. When rotating the first motor in a backward rotation direction opposite to the certain forward rotation direction and rotating the second motor in the forward rotation direction, the controller determines rotation speeds of the first motor and the second motor within a range indicated by Expression (1).

The disclosure relates to a dual-speed final drive control method and terminal device, and a storage medium. The method includes: when an absolute value of a gradient value of a road ahead is greater than a gradient threshold, determining, according to the gradient value, whether the road ahead is an uphill section or a downhill section, thereby controlling all gears of a transmission to correspond to a higher final drive ratio or a lower final drive ratio in the dual-speed final drive. The disclosure can make use of the dual-speed-ratio final drive to the greatest extent to improve the economy in energy consumption of the entire vehicle.

A vehicle control device includes a processor and memory. The memory stores relation-defining data for defining a relation between a state of a vehicle and an action variable that is a variable relating to operations of a transmission installed in the vehicle. The processor is configured to execute acquisition processing, operation processing, reward calculation processing, updating processing, counting processing, and limiting processing. The processor is configured to output the relation-defining data updated so that an expected income is increased when the transmission is operated following the relation-defining data, based on an updating map.

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.

The present disclosure discloses a terrain based dynamic gear shift control method and system for a vehicle. The method includes: during running of a vehicle, obtaining a current terrain; according to the current terrain, the economic gear shift strategy, and the dynamic gear shift strategy, generating a current gear shift strategy curve; and according to the current gear shift strategy curve, controlling a transmission to perform gear shift. The present disclosure can make the vehicle have wider adaptability, and achieve a better dynamic balance between economy and dynamic performance.

A computer system (e.g., an on-board vehicle computer system) creates or updates a mapping of transmission gears and respective driveline ratios during operation of the vehicle. The system obtains a current engine speed and vehicle speed and calculates a current driveline ratio for the vehicle based on the current engine speed and vehicle speed. If the driveline is engaged, the system updates the mapping based at least in part on the current driveline ratio. Performing the update may include adding a new transmission gear or updating an existing transmission gear in the mapping, or removing a duplicate transmission gear from the mapping. Applications include cruise control, predictive cruise control, predictive shifting, and selecting a gear for a specific purpose (e.g., for descending a hill).