A method of operating a vehicle having an engine, a throttle valve and a throttle operator. A continuously variable transmission operatively connected to the engine has a driving pulley, a driven pulley, and a belt operatively connecting therebetween. A ground engaging member is operatively connected to the driven pulley. A piston is operatively connected to the driving pulley for applying a piston force thereto and thereby changing an effective diameter of the driving pulley. A control unit controls actuation of the piston and the piston force. The method includes determining at least one of the throttle operator and throttle valve position, detecting a parking/drive away condition indicative of one of a parking operation and a drive-away operation of the vehicle, and, responsive to the detection, actuating the piston and controlling the piston force based on the at least one of the throttle operator position and the throttle valve position.

A method of operating a vehicle having an engine, a throttle valve and a throttle operator. A continuously variable transmission is operatively connected to the engine and has a driving pulley, a driven pulley, and a belt operatively connecting therebetween. At least one ground engaging member is operatively connected to the driven pulley and includes at least one of a wheel and a track. A piston is operatively connected to the driving pulley for applying a piston force to the driving pulley when actuated and thereby changing an effective diameter of the driving pulley. A control unit controls actuation of the piston and the piston force. The method includes determining an engine speed, and controlling the piston force based on the engine speed.

A method for performing a cold start in a vehicle having a power-spat transmission with a hydrostatic element comprising hydrostatic units. Several cold-start steps are performed sequentially for a cold start, the length of at least one of the cold-start steps is adapted depending on a temperature representing the start temperature of the power-split transmission. A state of the power-split transmission deviating from the temperature of the power-split transmission is monitored, during the execution of at least one of the cold-start steps, and, depending on this state, a transition from the respective cold-start steps to the subsequent cold-start step is performed, thus adapting the length of time of the respective cold-start steps.

A vehicle includes an engine, a transmission, and a controller. The engine is configured to generate power. The transmission is configured to transfer power from the engine to at least one drive wheel to propel the vehicle. The controller is programmed to, in response to a command to shift the transmission and a corresponding command to decrease a torque of the engine to less than a threshold corresponding to a spark retard limit during the shift, (i) increase the pressure of an oncoming clutch to engage the oncoming clutch, (ii) retard an engine spark at the spark retard limit to reduce the torque of the engine to the threshold during the engagement of the oncoming clutch, and (iii) shutdown at least one cylinder of the engine to further reduce the torque of the engine to less than the threshold during the engagement of the oncoming clutch.

An electronic control unit controls a motor so that a torque applied to an input shaft does not exceed an upper limit torque. The electronic control unit sets so as to restrict the upper limit torque from a first torque to a second torque smaller than the first torque, and then return the upper limit torque to the first torque more gradually when a first condition that a driver is assumed to have felt a decrease in driving force output to driving wheels is met before the upper limit torque is returned than when the first condition is not met.

A control device that includes an electronic control unit that is configured to: detect an actual current value flowing through the solenoid valve; receive a current command value and the actual current value detected and generate a primary command voltage value while feeding back the current command value on the basis of the actual current value; calculate a dither command voltage value to cause a periodic voltage oscillation; filter the actual current value detected to remove a frequency corresponding to a period of the dither command voltage value and output the filtered actual current value; generate a secondary command voltage value by superimposing the dither command voltage value generated on the primary command voltage value generated; convert the secondary command voltage value generated into a PWM signal; and generate, on the basis of the PWM signal generated, an application voltage to be applied to the solenoid valve.

In one aspect, a method is provided or braking a work vehicle including an engine and a hydrostatic drive system including a hydraulic pump configured to be rotationally driven by the engine and a hydraulic motor fluidly coupled with the hydraulic pump through a closed hydraulic loop of the hydrostatic drive system. The hydraulic pump may be configured to fluidly drive the hydraulic motor. The method may include receiving an operator request to reduce a ground speed of the work vehicle. The method may include monitoring a fluid temperature of a hydraulic fluid associated with the closed hydraulic loop and automatically controlling at least one of a pump displacement of the hydraulic pump or a motor displacement of the hydraulic motor based on the operator request and the monitored fluid temperature to adjust hydrostatic braking of the work vehicle and thereby reduce the ground speed of the work vehicle.

A vehicle includes a transmission having a torque converter, an oncoming clutch, and a controller. The controller is programmed to, in response to a torque of the oncoming clutch exceeding an estimated average by a threshold during an engagement, increase the torque of the oncoming clutch via a feedforward command and adjust the torque of the oncoming clutch via a feedback command to compensate for deviations in the torque generated by the feedforward command during the engagement.

A vehicle includes a step-ratio automatic transmission having clutches engageable to provide forward and reverse gears, an electric machine selectively coupled to the transmission, a main pump powered by the electric machine and supplying oil to actuate selected transmission clutches, a gear selector configured for selecting a transmission gear, and a controller configured to stop the electric machine when the gear selector selects park or neutral, to operate the electric machine in a speed control mode using a higher controller gain in response to the gear selector selecting forward or reverse while the electric machine is stopped until the electric machine and the main pump reach a first speed threshold to reduce engagement delay of at least one of the transmission clutches, and to operate the electric machine using a lower controller gain when the electric machine and the main pump exceed the first speed threshold.

A method for controlling an automatic transmission includes reducing, by a controller, a number of rotation of the engine connected to the automatic transmission to the first number of rotation when a shifting of the automatic transmission is started. The method further includes reducing, by the controller, a line pressure that is a hydraulic pressure of a flow line that operates the automatic transmission when the shifting of the automatic transmission is started.