A vehicle control system in a vehicle having a continuously variable transmission (CVT) system with a clutch mechanism modulates a torque capacity of the clutch mechanism. The CVT system in the vehicle further includes a primary pulley, a secondary pulley and a CVT belt for transmitting a torque to wheels from a power source rotatably connected with an input shaft. The clutch mechanism includes a forward (FWD) clutch between the power source and a CVT pulley assembly. The vehicle control system detects a wheel slip of the CVT system and controls a torque capacity of the FWD clutch, and the system is configured for avoiding a slip of the CVT belt by dissipating a spike torque generated by the wheel slip.

Systems and methods are shown for electrically controllably transmitting power from a motor involving electrically controllably coupling the first input hub to a shuttle so that power is transmitted from the first input hub to the shuttle, providing for one-way rotation between the shuttle and a stationary chassis, and coupling the shuttle to an output hub with a spring such that energy is stored and released from the spring as the output hub rotates. Examples are shown that include controlling engaged and disengaged time intervals of the first input hub and shuttle to maintain a torque level at the output hub, such as by utilizing pulse width modulation or pulse frequency modulation. Examples are also shown involving electroadhesively coupling the first input hub to the shuttle.

A clutch control method is provided for a four-wheel-drive vehicle in which the main drive wheels are connected to a drive source, and the auxiliary drive wheels are connected via a friction clutch to the drive source. When the vehicle starts off due to an accelerator depressing operation, the friction clutch is engaged to distribute, a drive torque from the drive source to the main drive wheels and the auxiliary drive wheels. In this clutch control method, when the vehicle switches from a traveling state to a stopped state while maintaining in a travel shift position, a control is preformed to apply initial torque as an engagement torque control of the friction clutch while the vehicle is stopped. A magnitude of the initial torque is set to a magnitude that maintains a drive-system torsion state by transmitting torque to an auxiliary-drive-wheel drive system before the vehicle is stopped.

A clutch control device includes an engine, a gearbox, a clutch device configured to disconnect and connect power transmission between the engine and the gearbox, a clutch actuator configured to drive the clutch device and vary a clutch capacity, and an ECU configured to calculate a control target value of the clutch capacity, and the ECU determines whether an engine rotational number after downshifting by the gearbox enters a high rotation region and decreases the clutch capacity after downshifting when it is determined that the engine rotational number after downshifting enters the high rotation region.

Torque reduction control is executed for temporarily reducing a torque capacity of a reaction engagement device during a transition of a shift. The reaction engagement device is maintained in an engaged state from before the shift to after the shift such that a predetermined rotating element in an automatic transmission bears a reaction caused by progress of the shift resulting from a change of an engaging-side engagement device into an engaged state. Therefore, without delaying a change of the engaging-side engagement device into the engaged state, transmission of torque that is generated as a result of rattling during a transition of a shift is reduced. Thus, in shift control over the automatic transmission, shock at the time of rattling is reduced while a stop of a shift due to a delay in change of the engaging-side engagement device into the engaged state is prevented.

A method for the transmission and damping of a mean torque with a superposed alternating torque having an input and an output. The mean and superposed alternating torque is transmitted along a torque path from the input to the output area. An input speed is a mean speed and a superposed alternating component. A slip arrangement is provided in the torque path between the input and the output for transmitting the mean and superposed alternating torque and generating a speed slip between an input speed and an output speed. The slip arrangement provides a maximum of an external activation of the speed slip in a area of the maxima of at least one periodic oscillation component of the alternating component and provides a minimum of an external activation of the speed slip in an area of the minima of at least one periodic oscillation component of the alternating component.

A method for the transmission and damping of a mean torque with a superposed alternating torque in an arrangement having an input and an output. The mean torque and superposed alternating torque are transmitted along a path from the input to the output. A slip arrangement is provided in the torque path between the input and the output for transmitting mean torque and superposed alternating torque and for generating a speed slip between an input speed and an output speed in the path. The slip arrangement provides a maximum of an external activation of the speed slip in the area of the maxima of at least one periodic oscillation component of the alternating component and provides a minimum of an external activation of the speed slip in the area of the minima of at least one periodic oscillation component of the alternating component.

A method for transmission of and damping of a mean torque with a superposed alternating torque in a torque transmission arrangement for a powertrain of a motor vehicle having an input and an output. The mean torque with the superposed alternating torque is transmitted along a torque path from the input the output. The input rotates at an input speed and the output rotates at an output speed. A slip arrangement is provided in the torque path between the input and the output for generating a speed slip. The slip arrangement provides a maximum of an external activation of the speed slip in the area of a maxima of at least one periodic oscillation component of an alternating component and provides a minimum of an external activation of the speed slip in the area of a minima of at least one periodic oscillation component of the alternating component (new).

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 method and a system for controlling a backlash of a powertrain included in a vehicle in connection with a gear shifting operation is presented. The method comprises: controlling, in connection with a first gear shifting operation, a clutch included in the powertrain to a slipping position, in which slipping position the clutch transfers a slipping torque that is less than a torque being transferred in a closed position for the clutch; analyzing a change of a rotational speed for an input shaft of a gearbox included in the powertrain; determining a position for the clutch, for which position the change of the rotational speed has a value corresponding to a backlash torque, the backlash torque having a predetermined value for eliminating the backlash; and utilizing the determined clutch position for controlling the clutch in connection with a second subsequent gear shifting operation.