The present document relates to a driveline for a vehicle, the driveline comprising a hydrodynamic retarder, a first driveline component such as a transmission input, and a controller configured to activate the hydrodynamic retarder at a point in time which is determined based on a rotational acceleration of the first driveline component. The present document further relates to a method of controlling a hydrodynamic retarder.

A control device for a continuously variable transmission includes a wheel speed difference sensing section configured to sense a wheel speed difference between the driving wheel and the driven wheel from a detection value of the first rotation speed sensor and a detection value of the second rotation speed sensor; and a clamping force increasing section configured to increase a clamping force for sandwiching a belt of the continuously variable transmission by a pulley when the wheel speed difference becomes equal to or greater than a first predetermined value, relative to a case where the wheel speed difference is smaller than the first predetermined value.

A method for controlling a vehicle installed with an automatic transmission, includes: a sudden stop determination step in which a controller determines whether the vehicle has stopped at a speed greater than or equal to a reference deceleration speed and whether a post-stop elapsed time is within a first reference time; a takeoff determination step in which the controller determines whether an input torque of the transmission exceeds zero within the first reference time when a shift range is in a driving range; a pressure control step in which, when the vehicle takes off, the controller elevates a line pressure of the transmission; a limitation determination step in which if a slippage extent of a turbine exceeds a reference slippage value for a second reference time, the controller limits the takeoff; and a torque reduction step in which the controller reduces a takeoff torque input of the transmission.

A method of controlling a transmission for a vehicle may include performing deceleration intention determination, by a controller, of determining an intention of a driver for deceleration based on whether a brake pedal signal is received by the controller, upon determining that the driver intends to decelerate, performing downshift determination, by the controller, of determining an intention of the driver to use engine braking based on whether manual downshift of a shifter is performed by the driver, upon determining that the driver intends to use the engine braking, performing continuous shifting determination, by the controller, of determining whether the driver intends to implement maximum engine braking through continuous shifting, and upon determining that the driver has the intention to implement the maximum engine braking, performing continuous shifting, by the controller, of implementing maximum engine braking by shifting to a lowest gear implementable under a current driving condition.

A method to control a road vehicle provided with a servo-assisted transmission during a slowing down phase; the control method generally includes, when the servo-assisted transmission is in an automatic operating mode, the steps of: calculating, assuming that a pressing of the brake pedal remains constant, an opening time interval needed to allow the road vehicle to reach an opening speed at which a clutch of the servo-assisted transmission is definitively opened; calculating a number of downshifts that can be carried out in the opening time interval based on a time needed to carry out a downshift; scheduling the downshifts to be carried out in order to get from the current gear engaged in the servo-assisted transmission to an opening gear with which the clutch of the servo-assisted transmission is definitively opened, so as to carry out no more than the number of downshifts that can be carried out in the opening time interval; and carrying out the scheduled downshifts.

A control apparatus for a vehicle having a step-variable transmission. The control apparatus includes: a shift control portion to temporarily increase an input torque of the step-variable transmission beyond a required value, the shift control portion commanding an engaging-side coupling device which is the coupling device placed in a released state, to be brought into an engaged state, when the input speed has been raised to a predetermined value; and a torque increasing amount setting portion to set an amount of increase of the input torque of the step-variable transmission beyond the required value, such that the amount of increase is smaller when a rate of change of a running speed of the vehicle is relatively low than when the rate of change is relatively high, the rate of change of the running speed having a negative value in a decelerating state of the vehicle.

A vehicle control method is provided for controlling a vehicle in which a clutch provided on a power transmission path between an engine and a drive wheel is disconnected when a shift range is a non-driving range and the clutch is connected when the shift range is a driving range. The vehicle control method controls the engine to a prescribed idling speed, controls engine torque to a negative torque by delaying an ignition timing of the engine; and causes the prescribed idling speed to drop within a prescribed amount of time needed for the clutch to switch from being disconnected to being connected when the shift range is switched from the non-driving range to the driving range.

A method for controlling gear shifting, including: acquiring a current gear-shifting parameter of the vehicle (101); according to the current gear-shifting parameter and a preset target rotational speed, determining a gear-shifting inputted rotational speed (102); and when a rotational speed of the vehicle reaches the gear-shifting inputted rotational speed, controlling a shifting fork to start up a gear-shifting operation (103). The method for controlling gear shifting presets the target rotational speed of the gears, and, according to the current gear-shifting parameter of the vehicle that is acquired in real time and the preset target rotational speed, inversely calculates the gear-shifting inputted rotational speed, whereby the gear-shifting inputted rotational speed is an accurate gear-shifting inputted rotational speed that matches with the current condition of the vehicle. When the rotational speed of the vehicle reaches the gear-shifting inputted rotational speed, the shifting fork is controlled to start up a gear-shifting operation, which can realize the accurate gear shifting of the vehicle, which greatly improves the stability of the vehicle when a dual-clutch automatic transmission is performing gear shifting.

A method to control a road vehicle provided with a servo-assisted transmission during a slowing down phase; the control method comprises, when the servo-assisted transmission is in an automatic operating mode, the steps of: calculating, assuming that a pressing of the brake pedal remains constant, an opening time interval needed to allow the road vehicle to reach an opening speed at which a clutch of the servo-assisted transmission is definitively opened; calculating a number of downshifts that can be carried out in the opening time interval based on a time needed to carry out a downshift; scheduling the downshifts to be carried out in order to get from the current gear engaged in the servo-assisted transmission to an opening gear with which the clutch of the servo-assisted transmission is definitively opened, so as to carry out no more than the number of downshifts that can be carried out in the opening time interval; and carrying out the scheduled downshifts.

A method for controlling gear shifting, including: acquiring a current gear-shifting parameter of the vehicle (101); according to the current gear-shifting parameter and a preset target rotational speed, determining a gear-shifting inputted rotational speed (102); and when a rotational speed of the vehicle reaches the gear-shifting inputted rotational speed, controlling a shifting fork to start up a gear-shifting operation (103). The method for controlling gear shifting presets the target rotational speed of the gears, and, according to the current gear-shifting parameter of the vehicle that is acquired in real time and the preset target rotational speed, inversely calculates the gear-shifting inputted rotational speed, whereby the gear-shifting inputted rotational speed is an accurate gear-shifting inputted rotational speed that matches with the current condition of the vehicle. When the rotational speed of the vehicle reaches the gear-shifting inputted rotational speed, the shifting fork is controlled to start up a gear-shifting operation, which can realize the accurate gear shifting of the vehicle, which greatly improves the stability of the vehicle when a dual-clutch automatic transmission is performing gear shifting.