Abstract: A vehicle powertrain includes a propulsion unit having a propulsion unit auxiliary brake, a transmission, driven wheels and a control unit arranged to control at least the transmission, where the propulsion unit is drivingly connected to the driven wheels via a clutch and different engagable gear ratios in the transmission.

Abstract: A vehicle powertrain includes a propulsion unit having a propulsion unit auxiliary brake, a transmission, driven wheels and a control unit arranged to control at least the transmission, where the propulsion unit is drivingly connected to the driven wheels via a clutch and different engagable gear ratios in the transmission.

Abstract: A method is provided for controlling an automatic transmission unit including at least a transmission with different selectable gear ratios and a clutch and being associated with a propulsion unit for a vehicle. The method includes operating the vehicle at a prevailing vehicle speed (v) in a downslope with the automatic transmission unit in a neutral gear or disengaged from the propulsion unit; operating the propulsion unit in an idle mode of operation; controlling the automatic transmission unit so as to select a gear which is a relatively low gear with regard to the prevailing vehicle speed (v), while maintaining the automatic transmission unit in a neutral gear or disengaged from the propulsion unit; and engaging the clutch to be slipping between the propulsion unit and the automatic transmission unit in order to adapt the rotational speed of the propulsion unit to the gear ratio of the relatively low gear.

Abstract: A method is provided for controlling an automatic transmission unit including at least a transmission with different selectable gear ratios and a clutch and being associated with a propulsion unit for a vehicle. The method includes operating the vehicle at a prevailing vehicle speed (v) in a downslope with the automatic transmission unit in a neutral gear or disengaged from the propulsion unit; operating the propulsion unit in an idle mode of operation; controlling the automatic transmission unit so as to select a gear which is a relatively low gear with regard to the prevailing vehicle speed (v), while maintaining the automatic transmission unit in a neutral gear or disengaged from the propulsion unit; and engaging the clutch to be slipping between the propulsion unit and the automatic transmission unit in order to adapt the rotational speed of the propulsion unit to the gear ratio of the relatively low gear.

Abstract: A method and device are provided for controlling disengagement of an automated vehicle master clutch arranged in a vehicle drivetrain between a vehicle propulsion unit and a step geared transmission. The method includes the steps of determining a first output torque of the propulsion unit prior to initiation of a master clutch disengagement procedure, computing a second output torque of the propulsion unit in dependence of at least the first output torque, and where the second output torque is closer to zero torque than the first output torque, initiating the master clutch disengagement procedure by initiating an oscillation in drive shafts by abruptly altering propulsion unit output torque from the first to the second output torque, and disengaging the master clutch when the oscillation has reached a first oscillation turning point. Benefits can include faster gear shifting and better comfort with maintained transmission durability.

Abstract: A method and a system for calibrating an estimated clutch characteristic curve of a dual-clutch vehicle transmission are provided. The method includes mechanically interconnecting a first input shaft with a second input shaft, whereby a transmission output shaft is disengaged; controlling, according to a first alternative, a regulating parameter of a first clutch regulator such that a first friction clutch is engaged with a first torque transmission capability, that a second friction clutch (initially is disengaged, and subsequently engaged; or according to a second alternative, that the second friction clutch is initially engaged, a regulating parameter of the first clutch regulator such that the first friction clutch is engaged with a first torque transmission capability, and that the second friction clutch subsequently disengaged; calculating a torque transmission capability of the second friction clutch; and adjusting an estimated clutch characteristic curve of the second friction clutch.

Abstract: Method for protecting a clutch of a vehicle, said vehicle being provided with an engine, drive wheels and an automated manual transmission for transmitting drive power from said engine to said drive wheels. A controller can execute the steps of: sensing a power demand from the driver which results in a clutch control where the clutch is partly engaged and clutch slip occurs, measuring travelling distance(s) of the vehicle during a predetermined first time interval, initiating a first warning measure, in order to alert the driver of excessive clutch slip, if the vehicle has traveled less than a predetermined distance during said predetermined first time interval.

Abstract: A method and device are provided for controlling disengagement of an automated vehicle master clutch arranged in a vehicle drivetrain between a vehicle propulsion unit and a step geared transmission. The method includes the steps of determining a first output torque of the propulsion unit prior to initiation of a master clutch disengagement procedure, computing a second output torque of the propulsion unit in dependence of at least the first output torque, and where the second output torque is closer to zero torque than the first output torque, initiating the master clutch disengagement procedure by initiating an oscillation in drive shafts by abruptly altering propulsion unit output torque from the first to the second output torque, and disengaging the master clutch when the oscillation has reached a first oscillation turning point. Benefits can include faster gear shifting and better comfort with maintained transmission durability.

Abstract: Method for protecting a clutch of a vehicle, said vehicle being provided with an engine, drive wheels and an automated manual transmission for transmitting drive power from said engine to said drive wheels. A controller can execute the steps of: sensing a power demand from the driver which results in a clutch control where the clutch is partly engaged and clutch slip occurs, measuring travelling distance(s) of the vehicle during a predetermined first time interval, initiating a first warning measure, in order to alert the driver of excessive clutch slip, if the vehicle has traveled less than a predetermined distance during said predetermined first time interval.