Systems and methods for operating a hybrid driveline that includes an engine, a motor/generator, and a driveline disconnect clutch are described. The systems and methods may improve vehicle efficiency while providing expected vehicle operation and performance. In one example, transmission line pressure is adjusted to match driveline disconnect clutch torque capacity to driver demand torque.

A vehicle launch control method may include judging, by a controller, whether or not a vehicle starts to be launched, determining, by the controller, target clutch torque through a designated first determination method and controlling a clutch based on the determined target clutch torque, upon judging that the vehicle starts to be launched, and determining, by the controller, target clutch torque through a designated second determination method differing from the first determination method and controlling the clutch based on the determined target clutch torque, when an engine speed variation and engine speed jerk respectively satisfy designated variation conditions and jerk conditions during determination of the target clutch torque through the first determination method and control of the clutch based on the determined target clutch torque.

A method for operating a motor vehicle includes, when a target differential speed is set for a separating clutch (4), determining a power transmission factor depending on the target differential speed and an internal combustion engine-driven torque to be transmitted by the separating clutch (4). The method also includes determining an actuating pressure for the separating clutch (4) depending on the power transmission factor, controlling the separating clutch (4) with the actuating pressure, ascertaining an actual differential speed forming at the separating clutch (4) depending on the actuating pressure, determining a corrected power transmission factor with a controller (10) depending on a deviation between the target differential speed and the actual differential speed, determining a corrected actuating pressure for the separating clutch (4) depending on the corrected power transmission factor and the internal combustion engine-driven torque to be transmitted, and controlling the separating clutch (4) with the corrected actuating pressure.

A control device is to be applied to a four-wheel drive vehicle including a first coupling device interposed between a rear-wheel final gear device and a rear left wheel axle and a second coupling device interposed between the rear-wheel final gear device and a rear right wheel axle. The control device includes a controller changes a coupling torque of the first coupling device and a coupling torque of the second coupling device independently of each other. The controller estimates, when the vehicle is accelerating, a vehicle body speed of the vehicle under a state in which the coupling torque of any one of the first coupling device and the second coupling device is set to a value larger than zero and the coupling torque of another one thereof is set to zero. Thereby, the control device can accurately estimate the vehicle body speed when the vehicle is traveling while accelerating.

A method is disclosed for reducing chatter vibrations of a friction clutch controlled automatically by a clutch actuator on the basis of a target clutch torque (M(s)) assigned to a clutch torque which is to be transmitted. The friction clutch is positioned in a drivetrain between an internal combustion engine and a transmission, having a present actual clutch torque which is marked by vibrations as a result of vibrations (M(i)). From a transmission behavior of the present actual clutch torque (M(i)), an absolute amplitude and a phase of an input signal detected at the output of the friction clutch and conveyed to a regulator are ascertained, and a phase-selective disturbance torque is ascertained. From the phase-selective disturbance torque, a phase-correct correction torque (M(k)) is determined, and the target clutch torque (M(s)) is corrected by the regulator. The correction torque (M(k)) is weighted with a specifiable intensification factor.

A driving force transmission control apparatus includes: a driving force transmission device that includes an electromagnetic clutch mechanism configured to generate a frictional force between clutch plates by energization of an electromagnetic coil and transmits a driving force by actuating the electromagnetic clutch mechanism; and a control device that controls the driving force transmission device. The control device includes a storage unit storing a hysteresis value representing the difference between a current value required to transmit a predetermined torque when an energization current to the electromagnetic coil is gradually increased and a current value required to transmit the predetermined torque when the energization current is gradually reduced, a torque command value calculator that calculates a torque command value, and a current command value calculator that calculates a current command value representing a target value of a current to be supplied to the electromagnetic coil based on the torque command value and the hysteresis value.

The invention relates to a method for reducing occasionally occurring vibrations, in particular chatter vibrations of a unit controlled automatically by an actuator, in particular a clutch actuator, on the basis of a target torque assigned to a clutch torque that is to be transmitted, in particular a target clutch torque, in particular a unit located in a drivetrain of a motor vehicle between a combustion engine and a transmission, in particular a friction clutch having an actual present clutch torque which is marked by vibrations as a result of occasionally occurring vibrations, wherein from an input signal which is representative of the vibration-marked torque on the basis of a known transfer behavior of the actual present torque vibration components of known form with unknown prefactors are continuously ascertained, a phase-correct correction torque is determined from these, and the target torque is corrected using the latter. In order to be able to separate a plurality of vibration components from one another and resolve them, an estimation model is made the basis of the input signal, and by means of the estimation model the prefactors are determined on the basis of a recursive method of the smallest square errors.

A method for parameterizing a software damper is disclosed. A target clutch torque affected in specified operating states by chatter vibrations is corrected by a software damper, wherein a transfer behavior of a clutch torque transferred via a friction clutch based on the target clutch torque is ascertained during a modulation of the target clutch torque. The software damper is parameterized with the help of the ascertained transfer behavior. To parameterize the software damper quickly and comprehensively, the target clutch torque is modulated by a broadband excitation in a frequency range of the chatter vibrations, and the transfer behavior is ascertained depending on operating parameters of the drivetrain.

A clutch torque control method for a dual clutch transmission (DCT) vehicle may include a shift initiation determining step of determining whether power-on downshift in which a driver steps on an accelerator pedal to change a current shift stage to a lower shift stage is initiated, and a torque correcting step of correcting basic control torque according to torque-stroke (TS) curve characteristics for controlling a disengagement-side clutch within a real shift range in which a number of rotations of an engine is changed with observer torque calculated by a torque observer when the power-on downshift is initiated, and determining the corrected basic control torque into control torque of the disengagement-side clutch.

A method for controlling a clutch includes judging whether or not a slip amount of the clutch is reduced to below a first reference value by a controller after starting of the vehicle is launched, judging whether or not accumulated slip energy of the clutch until a present time from the launch of starting the vehicle is a second reference value or more, as a result of judgment as to the slip amount of the clutch, if the slip amount of the clutch is below the first reference value, and controlling engagement of the clutch so as to prevent overheating of the clutch while the controller causes an engine to maintain a target engine speed, as a result of the judgment as to the accumulated slip energy, if the accumulated slip energy is the second reference value or more.