A method and system are provided for operating a lockup clutch of a torque converter of a motor vehicle. The torque converter includes a pump rotatably driven by a drive unit, a rotatable turbine fluidly coupled to the pump and configured to drive an input shaft of a transmission, and a lockup clutch selectively engageable to non-fluidically couple the pump to the turbine to transmit torque from the drive unit to the transmission. The operation of the lockup clutch is controlled by the system in response to detecting that the motor vehicle is coasting.

An apparatus and a method for controlling a transmission of a vehicle may include a determining device configured to determine whether to perform a front-vehicle-based deceleration following control based on information on the vehicle and information on the front vehicle when coasting of the vehicle is started, a calculating device configured to determine a target speed of the vehicle and a target distance based on a position, a speed, and a moving distance of the front vehicle, when the front-vehicle-based deceleration following control is determined to be performed, a gearshifting stage deciding device configured to decide a final gearshifting stage of the transmission based on the determined target speed and the target distance by configuring a deceleration profile for each gearshifting stage of the transmission, and a controller to control the transmission based on the final gearshifting stage.

A method of controlling an engine and a transmission of a vehicle includes: determining, by a controller, whether the engine is restarted after releasing the vehicle's SSC (Start & Stop coasting) or whether the vehicle is accelerating during NCC (Neutral Coasting control), determining an RPM and gear stage of the transmission if it is determined that the engine is restarted after releasing the vehicle's SSC or the vehicle is accelerating during NCC, determining a mild hybrid starter and generator (MHSG) target RPM and an MHSG target RPM gradient of the vehicle, performing, by the controller, MHSG RPM control of the vehicle to follow the MHSG target RPM and the MHSG target RPM gradient, determining whether the MHSG RPM slips compared to the MHSG target RPM, and performing proportional-integral-derivative (PID) control to follow the MHSG target RPM if the MHSG RPM slips compared to the MHSG target RPM.

The disclosure provides a control method, a control device for vehicular automatic transmission, and a recording medium. The control device includes an ON/OFF control solenoid controlling LC to either ON or OFF, and an LC pressure control linear solenoid controlling LC pressure between a released state and a fully engaged state. The control device acquires, when an accelerator pedal opening of a vehicle is on a deceleration side in a fully closed state, a torque converter slip ratio when the ON/OFF control solenoid maintains ON for a predetermined time period and the LC pressure control linear solenoid is controlled such that the LC pressure is OFF, and determines whether or not the second solenoid has a high-pressure fixation failure according to whether or not the slip ratio is within a predetermined range from a slip reference value.

A vehicle control device comprising: a balance gradient calculation unit configured to calculate a balance gradient that is a gradient at which a propulsive force of the vehicle and a resistance force applied to the vehicle are balanced when the vehicle travels in a gear-in coasting state in which an engine is connected to a gear and the vehicle travels without supplying fuel to the engine, in a case where a traveling state of the vehicle is a neutral coasting state; and a traveling control unit configured to: switch, based on the calculated balance gradient and a specified road gradient, the traveling state of the vehicle from the neutral coasting state to the gear-in coasting state in a case where the traveling state of the vehicle is the neutral coasting state; and end, the gear-in coasting state when determining that an end condition is satisfied.

A method to control the execution of a shift to a higher gear with a released accelerator pedal in a drivetrain provided with a dual-clutch, servo-assisted transmission, comprising the steps of: opening, in a first instant, an outgoing clutch; closing, in the first instant, an incoming clutch; synchronizing, between a second instant and a third instant, a rotation speed of the internal combustion engine with a rotation speed of the incoming clutch, namely with the rotation speed imposed by the gear ratio of the following gear; completely opening, in the third instant, the outgoing clutch; completely closing, in the third instant, the incoming clutch; keeping the torque transmitted by the outgoing clutch constant between the second instant and a fourth instant; and keeping the torque transmitted by the incoming clutch constant between the second instant and the fourth instant.

A method of controlling an engine and a transmission of a vehicle includes: determining, by a controller, whether the engine is restarted after releasing the vehicle's SSC (Start & Stop coasting) or whether the vehicle is accelerating during NCC (Neutral Coasting control), determining an RPM and gear stage of the transmission if it is determined that the engine is restarted after releasing the vehicle's SSC or the vehicle is accelerating during NCC, determining a mild hybrid starter and generator (MHSG) target RPM and an MHSG target RPM gradient of the vehicle, performing, by the controller, MHSG RPM control of the vehicle to follow the MHSG target RPM and the MHSG target RPM gradient, determining whether the MHSG RPM slips compared to the MHSG target RPM, and performing proportional-integral-derivative (PID) control to follow the MHSG target RPM if the MHSG RPM slips compared to the MHSG target RPM.

A method is disclosed for operating a multi-gear vehicle transmission in a motor vehicle during a coasting phase. The coasting phase includes an overrun phase with a driving gear engaged and a freewheeling phase with the neutral gear engaged. It is determined whether the motor vehicle is in the overrun phase of the coasting phase, whether a condition for a transition to the freewheeling phase of the coasting phase is fulfilled, and whether a transmission condition with elevated drag losses exists. If the motor vehicle is in the overrun phase of the coasting phase, if the condition for transition to the freewheeling phase is fulfilled, and if a transmission condition with elevated drag losses exists, then at least one further shifting element (D, E) is closed in addition to the shifting elements (A, B, C) of the driving gear, which are closed during the overrun phase of the motor vehicle.

The controller starts an output of an engagement instruction of the lockup clutch when a vehicle speed becomes a lockup start vehicle speed under a state where the lockup clutch is disengaged. When the vehicle speed, which is obtained a predetermined time after the output of the engagement instruction is started due to the vehicle speed becoming the lockup start vehicle speed, has reached a predetermined vehicle speed, the controller continues the output of the engagement instruction. When the vehicle speed has not reached the predetermined vehicle speed, the controller stops the output of the engagement instruction and restarts the output of the engagement instruction when the vehicle speed reaches a lockup restart vehicle speed which is set to a vehicle speed higher than the lockup start vehicle speed while the output is stopped.

The present invention provides a shift control method implemented in a vehicle equipped with an automatic transmission for controlling an input shaft rotation speed to a target input shaft rotation speed during a shift. The method includes setting of a basic target synchronization rotation speed that is a basic target value of the input shaft rotation speed during the shift, and setting of a corrected target input shaft rotation speed as the target input shaft rotation speed when the shift is a downshift without a requirement for a driving force of the vehicle, The corrected target input shaft rotation speed is obtained by decreasingly correcting the basic target synchronization rotation speed. Further, a decreasing correction amount of the basic target synchronization rotation speed is set so as to become larger as a deceleration of the vehicle becomes larger.