A method of operating a vehicle drivetrain for rocking the vehicle free. The drivetrain has a transmission with an input and an output that can be coupled by a clutch. The input and output are connected to a drive aggregate and a drive output, respectively. The clutch is actuated based on driver actuation of an accelerator and a rotational speed of the drive output such that following accelerator actuation, when its actuation decreases, the clutch disengages with a first opening gradient. Then, based on a calculated point in time at which drive aggregate torque upon the clutch corresponds to torque on the clutch from the drive output, the clutch disengages with a second, smaller opening gradient. And depending on a rotational speed of the drive output relative to a limit value, the clutch either initiates or terminates engagement with a first closing gradient.

A method for controlling an automated starter clutch (4) in a drive train of a motor vehicle (1), which drive train has a transmission (3). In at least one first mode, the starter clutch (4) is operated automatically and is transitioned in an event-controlled manner into a second mode, in which the starter clutch (4) can be operated in such a way that upon actuation of the starter clutch (4), at least one jolt-like movement of the motor vehicle (1) is caused. In the second mode, the actuation of the starter clutch (4) is initiated and controlled depending upon operation of an accelerator pedal (13).

A method to control the execution of a shift to a higher gear with a released accelerator pedal in a drivetrain provided with a dual-clutch, servo-assisted transmission, comprising the steps of: opening, in a first instant, an outgoing clutch; closing, in the first instant, an incoming clutch; synchronizing, between a second instant and a third instant, a rotation speed of the internal combustion engine with a rotation speed of the incoming clutch, namely with the rotation speed imposed by the gear ratio of the following gear; completely opening, in the third instant, the outgoing clutch; completely closing, in the third instant, the incoming clutch; keeping the torque transmitted by the outgoing clutch constant between the second instant and a fourth instant; and keeping the torque transmitted by the incoming clutch constant between the second instant and the fourth instant.

Systems and methods for selecting and scheduling which of a plurality of engine starting devices starts an internal combustion engine of a hybrid vehicle are presented. In one example, a scheduled start of the internal combustion engine via a driveline disconnect clutch is withdrawn during conditions when both a transmission gear shift is requested or in process and when a driver urgency level is greater than a threshold level.

The present invention provides a new clutch system that ensures a 100% torque transmission rate between an engine and a transmission in a vehicle system, that can be commonly applied to conventional manual transmission vehicles and automatic vehicles, and that operates in conjunction with an accelerator pedal and a brake pedal.

A method for controlling an automated starter clutch (4) in a drive train of a motor vehicle (1), which drive train has a transmission (3). In at least one first mode, the starter clutch (4) is operated automatically and is transitioned in an event-controlled manner into a second mode, in which the starter clutch (4) can be operated in such a way that upon actuation of the starter clutch (4), at least one jolt-like movement of the motor vehicle (1) is caused. In the second mode, the actuation of the starter clutch (4) is initiated and controlled depending upon operation of an accelerator pedal (13).

A method of operating a vehicle drivetrain for rocking the vehicle free. The drivetrain has a transmission with an input and an output that can be coupled by a clutch. The input and output are connected to a drive aggregate and a drive output, respectively. The clutch is actuated based on driver actuation of an accelerator and a rotational speed of the drive output such that following accelerator actuation, when its actuation decreases, the clutch disengages with a first opening gradient. Then, based on a calculated point in time at which drive aggregate torque upon the clutch corresponds to torque on the clutch from the drive output, the clutch disengages with a second, smaller opening gradient. And depending on a rotational speed of the drive output relative to a limit value, the clutch either initiates or terminates engagement with a first closing gradient.

A controller executes a method to manage an engine connect/disconnect decision in a powertrain having an engine, transmission, electric machine, and a battery pack and power inverter module (“TPIM”). In response to vehicle ground speed being less than a calibrated maximum electric vehicle accelerator pedal signal (“EV.sub.APS”) level, the controller calculates a delta APS (“ΔAPS”) value by subtracting a scaled APS value from the actual APS level. The scaled APS value is a scaled variant of a maximum EV.sub.APS value selected from a maximum EVS.sub.APS table, the latter populated based on inverter temperature, state of charge of the battery pack, and ground speed. When the ΔAPS value exceeds a threshold, the controller connects the engine to the transmission via an engine disconnect clutch. The engine is disconnected based on acceleration of the vehicle and the above-noted factors.

A launch control method for a vehicle may include a step of increasing clutch torque of a clutch according to a decrease in braking pressure, a step of maintaining a current level of the clutch torque for a first reference duration, a step of gradually reducing the clutch torque within a range which is lower than the first reference torque level and is equal to or greater than a second reference torque level which is lower than the first reference torque level, a step of gradually increasing the clutch torque until the clutch torque reaches a third reference torque level which is higher than the first reference torque level, and a step of bringing the control to a stop when a state in which a clutch slip is less than a predetermined critical synchronous slip is maintained for a predetermined critical synchronization duration or longer than the predetermined critical synchronization duration.

A mean rate decision method for a clutch motor is disclosed. The method includes determining whether the clutch motor and a gear sensor are in an electrical failure state; when it is determined the clutch motor and the gear sensor are not in the electrical failure state, determining whether there is a driver's starting intention on the basis of state information on the clutch pedal; setting a target position of the clutch motor according to a pedal setting value set by the clutch pedal; and when it is determined that there is no driver's starting intention and that an actual position of the clutch motor exceeds the target position of the clutch motor, determining a failure of the clutch motor on the basis of an excess movement amount and an excess duration in the excess state.