A transmission gear control apparatus for a vehicle is provided. The vehicle includes an automatic transmission, a torque converter, and an accelerator operation amount sensor. The torque converter is disposed between the engine and the automatic transmission. The transmission gear control apparatus includes an electronic control unit. The electronic control unit is configured to: (i) control switching of a transmission gear stage of the automatic transmission at least on a basis of a change in vehicle speed of the vehicle; (ii) control lockup of a lock-up clutch of the torque converter on a basis of a state of the vehicle; and (iii) control the automatic transmission when the accelerator operation amount is equal to or larger than a specified value such that an upshift of the automatic transmission is performed at a higher vehicle speed as a rotation difference between input and output of the torque converter is reduced.

In the case where the lockup clutch is in the complete engagement state when a changeover between shift stages is made with the second shift mode selected, an electronic control unit holds the lockup clutch in the complete engagement state. Meanwhile, in the case where the lockup clutch is in the slip engagement state, the electronic control unit holds the lockup clutch in the slip engagement state based on a slip amount of the torque converter, or switches the lockup clutch to the complete engagement state.

A controller includes a control unit which is configured to execute a coast stop control. The coast stop control is configured to perform automatic stopping of the drive source while the vehicle is traveling, when a permitting condition is satisfied, the permitting condition including a condition that a speed ratio R of the variator is lower than a first threshold R1 while the lock-up clutch is in an engaged phase. The control unit is configured to prohibit execution of the coast stop control in a case in which an input-output rotation speed difference of the torque converter is equal to or more than a predetermined value when the lock-up clutch is in the engaged phase.

A method of controlling a hybrid vehicle is provided, which includes shifting a friction engagement element from a released state to a slipping or engaged state, and performing motor control where an engine is started using a motor in response to a startup demand of the stopped engine during vehicle traveling, applying as the motor control a first control in which a target speed to be set for the motor is instructed and feedback control of the motor is executed based on a speed detected by a motor speed sensor to be the target speed, determining whether a condition for switching the motor control from the first control to a second control in which a target torque to be outputted from the motor is instructed to cause the motor to output the target torque, is satisfied, and when determined to be satisfied, switching the motor control to the second control.

Systems and control methods can provide for determining a TrnAin torque request from desired vehicle acceleration in a vehicle that utilizes a WTC architecture to allow for smooth transition between different transmission states, such as torque converter bypass clutch states and shifts between transmission gear ratios. The methods provide consistent and smooth vehicle acceleration profile during transmission state transitions. The methods also provide the ability to track the desired vehicle acceleration consistently from virtual driver demand sources, such as adaptive cruise control, autonomous vehicle, or remote parking, without allocating any additional resource to account for transmission state transitions. The proposed methods are applicable to any TC-based automatic transmission drivetrain, such as conventional powertrain, MHT, P4 HEV, or even BEV powertrains where the motor is located on the impeller side of a torque converter.

A vehicle control device controls a vehicle including an internal combustion engine, an electric motor, a drive wheel, and a lock-up clutch provided in a power transmission path from the internal combustion engine and the electric motor to the drive wheel. The vehicle control device is configured to: not execute a motor vibration damping control and a slip vibration damping control in a non-vibration damping region; execute the motor vibration damping control and the slip vibration damping control in a first vibration damping region in a high load state or a low rotation speed state; and execute the motor vibration damping control and not execute the slip vibration damping control in a second vibration damping region in a medium load state or a medium rotation speed state.

A method for determining transmission and/or clutch parameters of a motor vehicle automatic transmission having at least one clutch, in particular for basic calibration of the transmission, in particular an automated manual transmission and/or a dual-clutch transmission, includes determining drag torque and/or kiss point of the clutch using an actuable synchronization device. The clutch has at least one drive side connected to an internal combustion engine output shaft and at least one output side connected to a transmission input shaft. The transmission output and/or drive shaft is blocked. The drive side of the clutch is driven. Basic calibration of the transmission is improved by driving the drive side of the clutch by an electric motor, providing a freewheel-shifted gear stage, and driving the drive side of the clutch by the electric motor in a rotation direction opposite the internal combustion engine output shaft.

A method controls an internal combustion engine having a drive output shaft that is coupled to an input shaft of a transmission. The internal combustion engine and the transmission are encompassed by a drivetrain for the drive of a motor vehicle. The method includes determining a rotational speed of the drive output shaft of the internal combustion engine and determining a rotational acceleration of the drive output shaft based on the rotational speed of the drive output shaft. A dynamic torque of the internal combustion engine is determined as a product of the rotational acceleration and a dynamic moment of inertia of the internal combustion engine. A maximum combustion torque of the internal combustion engine is determined from a sum of a predetermined maximum torque at the input shaft of the transmission and the dynamic load torque of the internal combustion engine.

A controller of a vehicle that includes a return control unit configured to carry out a complete engagement control of a power connecting/disconnecting device. At the time a return condition from inertia traveling to normal traveling is established and a down shift of an automatic transmission is requested, the return control unit carries out a down shift control of the automatic transmission so that a difference between an increasing gradient of a rotating speed of a first engaging portion and an increasing gradient of a rotating speed of a second engaging portion is within a predetermined range. At the time it can be regarded that the rotating speed of the first engaging portion and the rotating speed of the second engaging portion are synchronized, the return control unit completely engages the power connecting/disconnecting device.

A method for starting a combustion engine of a hybrid motor vehicle drivetrain, in which there is a connection clutch interposed between the combustion engine and the electric motor for transmitting a torque between the combustion engine and the electric motor, and a main clutch interposed between the gearbox and the electric motor. From an initial state in which the electric motor generates a drive torque and the combustion engine is stopped, the main clutch is kept in a closed state so as to transmit the torque generated by the electric motor to the gearbox, and the connection clutch is controlled so as to transmit a drive torque between the electric motor and the combustion engine and perform a torque-limiting function between the combustion engine and the electric motor in order to limit the transmission of acyclisms between the combustion engine and the electric motor.