An automatic transmission that includes a speed change mechanism including a gear mechanism that can attain a plurality of shift speeds, and a plurality of friction engagement elements that are selectively engaged to attain each shift speed in the gear mechanism; a hydraulic control device that can regulate engagement pressures to be supplied to hydraulic servos of the plurality of friction engagement elements and that can supply lubricating oil that lubricates the speed change mechanism; and a control unit that sends a command about the engagement pressures to the hydraulic control device to control engagement states of the plurality of friction engagement elements.

A vehicle includes a gear shifter operable to shift a manual transmission. An actuator is connected to the shifter and actuatable to bias the shifter to at least a first or second neutral position. The vehicle further includes a controller configured to bias the shifter, via the actuator, to one of the neutral positions based on a speed of the vehicle.

A HST system for use in traveling of a vehicle includes a controller that controls a pump regulator that changes a displacement of a pump and a motor regulator that changes a displacement of a motor. The controller determines whether or not a particular downhill travel condition is satisfied based on a result of detection by a vehicle speed detector that detects a vehicle speed of the vehicle and a result of detection by a rotation number detector that detects a number of rotations of an engine per unit time. In a case where a depression amount of an accelerator pedal, which is detected by a depression amount detector, is zero and the particular downhill travel condition is satisfied, the controller controls the motor regulator to increase the displacement of the motor.

A vehicle includes an engine, a torque converter, a transmission, and a control device. The torque converter is coupled to the engine. The transmission is coupled to the torque converter. The control device is configured to control operation of the transmission. The control device includes a controller configured to perform shift hold control to prevent upshift of the transmission based on a lateral acceleration value of the vehicle. The controller is configured to permit the upshift of the transmission by only one gear shift stage in a case where a predetermined condition is met in the shift hold control. The predetermined condition includes a condition that an index value indicating a rotation speed of an output shaft of the torque converter be higher than a first threshold value.

A vehicle includes an engine, a torque converter, a transmission, and a control device. The torque converter is coupled to the engine. The transmission is coupled to the torque converter. The control device is configured to control operation of the transmission. The control device includes a controller configured to perform shift hold control to prevent upshift of the transmission based on a lateral acceleration value of the vehicle. The controller is configured to permit the upshift of the transmission by only one gear shift stage in a case where a predetermined condition is met in the shift hold control. The predetermined condition includes a condition that an index value indicating a rotation speed of an output shaft of the torque converter be higher than a first threshold value.

Disclosed are a method and device for controlling the state switching of a fluid torque converter, a vehicle and a storage medium, the method including: obtaining a target instruction when the torque converter of the vehicle is in a locked state, the target instruction triggering a change in the torque transmission direction of a transmission system of the vehicle; obtaining a state parameter, and determining whether the current vehicle is in a target operating condition according to the state parameter; and if the current vehicle is in the target operating condition, switching the fluid torque converter to an open state, and switching the torque converter back to the locked state after maintaining the open state for a preset period of time.

Disclosed are a method and device for controlling the state switching of a fluid torque converter, a vehicle and a storage medium, the method including: obtaining a target instruction when the torque converter of the vehicle is in a locked state, the target instruction triggering a change in the torque transmission direction of a transmission system of the vehicle; obtaining a state parameter, and determining whether the current vehicle is in a target operating condition according to the state parameter; and if the current vehicle is in the target operating condition, switching the fluid torque converter to an open state, and switching the torque converter back to the locked state after maintaining the open state for a preset period of time.

Various methods and systems are provided for a shift assembly for a vehicle transmission. In one example, a shift assembly for a transmission includes a first barrel cam including a first cam track; a second barrel cam arranged coaxially with the first barrel cam and including a second cam track; a first motor configured to drive the first barrel cam independent of the second barrel cam; and a second motor configured to drive the second barrel cam independent of the first barrel cam.

Methods and systems are provided for improving torque control of a vehicle that includes simulated shifting of a step gear ratio transmission. In one example, a propulsive effort request is gradually incrementally increased or decreased to provide a smooth torque transition, thereby providing a smoother vehicle speed change and improve vehicle drivability.

An oil pressure estimation device for calculating an estimated differential pressure that is an estimated value of a differential pressure between two oil chambers generated in a torque converter including the two oil chambers and a lockup clutch includes a storage device and an execution device. The storage device stores mapping data defining a mapping, the mapping outputting as an output variable an estimated differential pressure variable indicating the estimated differential pressure, in response to input of an input variable, and the mapping having been trained by machine learning. The mapping includes an instruction differential pressure variable indicating the instruction differential pressure as one of a plurality of the input variables. The execution device executes an acquisition process of acquiring a value of the input variable and a calculation process of inputting the value of the input variable into the mapping to calculate a value of the output variable.