To reduce fuel consumption, a transmission is shifted into a neutral state, called neutral idle, when a vehicle stops in a drive mode. During a transition from a neutral idle state to an engaged state, the engine torque is controlled to avoid excessive shift energy and to mitigate acceleration drop. Specifically, the engine torque is set to a level equal to a sum of a transmission torque capacity and an offset, which is a function of accelerator pedal position. The transmission torque capacity is calculated based on the engaging shift element torque capacity and torque ratios associated with the kinematics and the torque converter. To accommodate noise factors such as variation over time, the offset function is adapted in response to measured clutch energy and acceleration drop.

Controlling a driving torque of a driveline assembly of a motor vehicle comprises: monitoring a speed of a first drive axle; monitoring a speed of a second drive axle; determining a target speed for the electric machine from at least one of the speeds of the first and the second drive axle controlling the electric machine in target speed mode as a function of the at least one speed; determining a target torque from the speed of the first drive axle and the speed of the second drive axle; controlling the clutch in a target torque mode as a function of the speed of the first drive axle and the speed of the second drive axle.

A system and method for modifying the engine pull-up (EPU) logic within a hybrid vehicle based on max motor torque that accounts for the drop or change in available motor torque due to the opening/slipping of a torque converter bypass clutch during engine starts is disclosed. An engine pull-up threshold is determined from max available motor torque at a virtual impeller speed, where the virtual impeller speed is the impeller speed that would result if the torque converter bypass clutch was open/slipping and transferring the same amount of torque.

A method for controlling a hybrid vehicle may include detecting, in a controller, a circumstance that a vehicle is rapidly decelerated and then rapidly accelerated; confirming that a transmission clutch slipped in the controller as a result of performing the detecting; reducing a driving torque and a motor speed while minimizing a hydraulic pressure of the transmission clutch in the controller, in the case that the transmission clutch has slipped as a result of performing the confirming; determining when the transmission clutch is available for synchronization in the controller while performing the reducing; and normalizing the hydraulic pressure of the transmission clutch and the driving torque in the controller, in the case that it is determined that the transmission clutch is available for synchronization as a result of performing the determining.

A method for stopping of a motor vehicle including providing a creep torque via a drive train of the motor vehicle and then increasing, independently of the driver, engine speed of a drive engine of the drive train to increase a drive torque of the drive engine and simultaneously increasing, independently of the driver, a braking torque of a brake system of the motor vehicle to balance the drive torque and the braking torque of the motor wherein the maximum braking torque is as great as the creep torque during a standstill of the motor vehicle. The method then maintains the braking torque and simultaneously reduces the engine speed of the drive engine to point at which the motor vehicle comes to a standstill. In an alternative embodiment the method includes applying, independently of the driver, a braking torque by a brake system of the motor vehicle, wherein the applied braking torque is as great as the creep torque present when the motor vehicle is at a standstill and then maintaining the braking torque and simultaneously reducing the creep torque of the drive train up to a point at which the motor vehicle comes to a standstill.

A control apparatus for a vehicular drive unit is provided. The vehicular drive unit includes a continuously variable transmission, and a clutch. The control apparatus includes an electronic control unit that is configured to acquire an oil temperature of hydraulic oil for controlling the continuously variable transmission and the clutch, and control the clutch such that a torque capacity of the clutch becomes smaller than a torque capacity that is set in a case where an oil temperature of the hydraulic oil is higher than a predetermined oil temperature, when the oil temperature is equal to or lower than the predetermined oil temperature, or control the continuously variable transmission such that a speed ratio of the continuously variable transmission becomes equal to or larger than a lower limit set in advance when the oil temperature of the hydraulic oil is equal to or lower than the predetermined oil temperature.

A vehicle includes a disconnect clutch selectively coupling an engine and an electric machine. The vehicle further includes a mechanical pump driven by the electric machine and operable to pressurize fluid for the clutch. The vehicle includes a controller programmed to, in response to the electric machine being inoperable, activate an auxiliary starter to start the engine, activate an electric pump operable to pressurize fluid to the clutch, and operate the engine to drive the mechanical pump.

A control system and method for controlling a multiple gear ratio automatic transmission in a powertrain for an automatic transmission having pressure activated friction torque elements to effect gear ratio upshifts. The friction torque elements are synchronously engaged and released during a torque phase of an upshift event as torque from a torque source is increased while allowing the off-going friction elements to slip, followed by an inertia phase during which torque from a torque source is modulated. A perceptible transmission output torque reduction during an upshift is avoided. Measured torque values are used during a torque phase of the upshift to correct an estimated oncoming friction element target torque so that transient torque disturbances at an oncoming clutch are avoided and torque transients at the output shaft are reduced.

A method of controlling a dual clutch transmission power on up shift including an on-coming clutch and an off-going clutch. The method includes implementing a prep phase comprised of decreasing torque on the off-going clutch, monitoring the off-going clutch speed to determine a slip point, and adding a bump torque to the off-going clutch when the off-going clutch reaches the slip point. The method implements a torque phase transferring torque from the off-going clutch to the on-coming clutch by increasing torque on the on-coming clutch towards an engine torque, decreasing torque on the off-going clutch, and simultaneously keeping the combination of torques greater than the slip point.

The present disclosure provides a shift control method for a hybrid electric vehicle including: controlling a speed of a vehicle driving source; simultaneously controlling a release element and a connection element in a transmission based on a rotation acceleration of a transmission output shaft when shifting by a power-on down shift.