A method ascertains a characteristic variable of a clutch installed into the powertrain of a vehicle for transmitting torque between a clutch input and a clutch output. A first electric motor is connected to the clutch input to introduce a first drive torque into the clutch. The torque is ascertained when the vehicle is at a standstill in that the clutch is first opened; the first electric motor is regulated at a first rotational speed; the clutch output is regulated at a second rotational speed; a counter torque which counteracts the transmission torque is applied to the clutch output; the clutch is then closed in order to assume a slipping state in which a specific differential rotational speed between the clutch input and the clutch output is present; the first drive torque is then ascertained; and the transmission torque is determined on the basis of the first drive torque.

A method ascertains a characteristic variable of a clutch installed into the powertrain of a vehicle for transmitting torque between a clutch input and a clutch output. A first electric motor is connected to the clutch input to introduce a first drive torque into the clutch. The torque is ascertained when the vehicle is at a standstill in that the clutch is first opened; the first electric motor is regulated at a first rotational speed; the clutch output is regulated at a second rotational speed; a counter torque which counteracts the transmission torque is applied to the clutch output; the clutch is then closed in order to assume a slipping state in which a specific differential rotational speed between the clutch input and the clutch output is present; the first drive torque is then ascertained; and the transmission torque is determined on the basis of the first drive torque.

A method ascertains a characteristic variable of a clutch installed into the powertrain of a vehicle for transmitting torque between a clutch input and a clutch output. A first electric motor is connected to the clutch input to introduce a first drive torque into the clutch. The torque is ascertained when the vehicle is at a standstill in that the clutch is first opened; the first electric motor is regulated at a first rotational speed; the clutch output is regulated at a second rotational speed; a counter torque which counteracts the transmission torque is applied to the clutch output; the clutch is then closed in order to assume a slipping state in which a specific differential rotational speed between the clutch input and the clutch output is present; the first drive torque is then ascertained; and the transmission torque is determined on the basis of the first drive torque.

A method ascertains a characteristic variable of a clutch installed into the powertrain of a vehicle for transmitting torque between a clutch input and a clutch output. A first electric motor is connected to the clutch input to introduce a first drive torque into the clutch. The torque is ascertained when the vehicle is at a standstill in that the clutch is first opened; the first electric motor is regulated at a first rotational speed; the clutch output is regulated at a second rotational speed; a counter torque which counteracts the transmission torque is applied to the clutch output; the clutch is then closed in order to assume a slipping state in which a specific differential rotational speed between the clutch input and the clutch output is present; the first drive torque is then ascertained; and the transmission torque is determined on the basis of the first drive torque.

A method for synchronizing a first drive element rotatable about an axis of rotation with a second drive element rotating about the axis of rotation at a target speed, of a powertrain of a motor vehicle, in which a synchronizing force is exerted on a synchronizing unit by an actuator. A speed, at which the first drive element rotates about the axis of rotation is adapted by the synchronizing unit to the target speed. The synchronizing force is increased during a first time span, so that the speed approaches the target speed. The synchronizing force is continuously reduced during a second time span following the first time span, before the speed corresponds to the target speed.

A control device for a clutch, which is provided between an operation machine and a drive shaft of an engine, controls an operation of a valve member for opening and closing an oil supply port through which an oil reservoir chamber and a torque transmission chamber communicate. The control device refers to a desired rotation speed of a rotating body of the operation machine and to an acquired rotation speed of the rotating body of the operation machine, calculates a proportional term manipulated variable based on a deviation between an angular acceleration of the rotating body and a desired angular acceleration, and controls the operation of the valve member on the basis of this calculated proportional term manipulated variable.

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, an engine rotational number sensor configured to detect an engine rotational number, a throttle opening angle sensor configured to detect a throttle opening angle, and a controller configured to calculate a control target value of the clutch capacity, wherein the controller calculates an estimated engine torque and causes the clutch device to change a slip clutch capacity according to the estimated engine torque.

A control device for a dutch, which is provided between an operating machine and a drive shaft of an engine, controls the operation of a valve member for opening and closing an oil supply hole through which an oil reservoir chamber and a torque transmission chamber communicate. The control device refers to a target rotational speed of a rotational solid of the operating machine and to the acquired rotational speed of the rotational solid of the operating machine, calculates a proportional manipulated variable based on the deviation between the angular acceleration of the rotational solid and a target angular acceleration, and controls the operation of the valve member on the basis of this calculated proportional manipulated variable.

The present disclosure relates to a vehicle (1) having a torque generating machine (4); and one or more driven wheel (W.sub.D). A driveline (6) is provided for transmitting torque from the torque generating machine (4) to said one or more driven wheel. The driveline (6) includes a torque transmitting means (8). A first decoupling mechanism (11) is operable to decouple the torque transmitting means (8) from the torque generating machine (4). The first decoupling mechanism (11) is closed to couple the torque transmitting means (8) to the torque generating machine (4) and is opened to decouple the torque transmitting means (8) from the torque generating machine (4). A second decoupling mechanism (12) is operable to decouple the torque transmitting means (8) from the one or more driven wheel. The second decoupling mechanism (12) is closed to couple the torque transmitting means (8) to the one or more driven wheel and is opened to decouple the torque transmitting means (8) from the one or more driven wheel. A controller (2) is provided having at least one electronic processor for controlling operation of the first and second decoupling mechanisms (11, 12). The at least one electronic processor (P) being configured to determine a target operating speed of the torque generating machine (4), control the operating speed of the torque generating machine (4) in dependence on the determined target operating speed, close the first decoupling mechanism (11) when the operating speed of the torque generating machine (4) at least substantially matches the determined target operating speed and close the second decoupling mechanism (12) after closing the first decoupling mechanism (11). The present disclosure relates to a corresponding method of controlling first and second decoupling mechanisms (11, 12) to control the transmittal of torque from a torque generating machine (4) to one or more driven wheel of a vehicle (1).

In an aspect, a method is provided for controlling a clutch assembly having first and second rotatable clutch members. The method includes providing a wrap spring clutch having first and second ends. The phase angle between the first and second ends determines a diameter of the wrap spring clutch. One of the clutch members is connected with the first end. The method further includes obtaining a target value indicative of a target speed for the second clutch member, and determining through measurement an actual value that is indicative of an actual speed of the second clutch member. The method further includes changing the phase angle between the first and second ends of the wrap spring clutch to generate a selected amount of slip between the wrap spring clutch and the other of the first and second clutch members, based on the target value and the actual value.