A method for serial operation of a motor vehicle with a transmission having a first electric machine, which is operated as a motor for driving the motor vehicle, and a second electric machine, which is operated as a generator, includes, after a generation of a change-over signal, switching the first electric machine from the operation as a motor to the operation as a generator, and switching the second electric machine from the operation as a generator to the operation as a motor in order to drive the motor vehicle.

A method for operating a motor vehicle drivetrain having a transmission connected between a drive aggregate and a drive output, a Power Take-Off (PTO) that can be coupled to the drive aggregate on drive aggregate side to take up drive torque from the drive aggregate. In order to determine the torque taken up by the PTO, the transmission is first shifted to interrupt torque to the transmission output. Thereafter, a defined torque is delivered by the drive aggregate, at least with the PTO coupled to the drive aggregate, and, during this at defined time-points, rotational speeds of a shaft driven by the drive aggregate are determined and from this an angular acceleration of the shaft is determined. A first torque of the shaft is determined from the shaft angular acceleration while the PTO is coupled. Based on the first torque, the torque taken up by the PTO is determined.

A method for operating a motor vehicle drivetrain having a transmission connected between a drive aggregate and a drive output, a Power Take-Off (PTO) that can be coupled to the drive aggregate on drive aggregate side to take up drive torque from the drive aggregate. In order to determine the torque taken up by the PTO, the transmission is first shifted to interrupt torque to the transmission output. Thereafter, a defined torque is delivered by the drive aggregate, at least with the PTO coupled to the drive aggregate, and, during this at defined time-points, rotational speeds of a shaft driven by the drive aggregate are determined and from this an angular acceleration of the shaft is determined. A first torque of the shaft is determined from the shaft angular acceleration while the PTO is coupled. Based on the first torque, the torque taken up by the PTO is determined.

One embodiment relates to a hybrid vehicle drive system for a vehicle including a first prime mover, a first prime mover driven transmission, a rechargeable power source, and a PTO. The hybrid vehicle drive system can include a control system for reducing or eliminating regenerative braking during a traction control or anti-lock braking event.

One embodiment relates to a hybrid vehicle drive system for a vehicle including a first prime mover, a first prime mover driven transmission, a rechargeable power source, and a PTO. The hybrid vehicle drive system can include a control system for reducing or eliminating regenerative braking during a traction control or anti-lock braking event.

A method for performing rotational speed synchronisation of a first transmission component having a first initial rotational speed with a second transmission component having a second initial rotational speed, so that they rotate with the same final rotational speed during a gear switch from an initial driving gear to a final driving gear in a stepped gear transmission for a hybrid electric or electric drive train having an electric traction motor. The method including calculating a total frictional work resulting from performing the total rotational speed synchronisation by means of a mechanical synchroniser of the stepped gear transmission only, and if the calculated total frictional work exceeds a maximal frictional work of the mechanical synchroniser, performing the rotational speed synchronisation by means of both the electric traction motor and the mechanical synchroniser.

A method for performing rotational speed synchronisation of a first transmission component having a first initial rotational speed with a second transmission component having a second initial rotational speed, so that they rotate with the same final rotational speed during a gear switch from an initial driving gear to a final driving gear in a stepped gear transmission for a hybrid electric or electric drive train having an electric traction motor. The method including calculating a total frictional work resulting from performing the total rotational speed synchronisation by means of a mechanical synchroniser of the stepped gear transmission only, and if the calculated total frictional work exceeds a maximal frictional work of the mechanical synchroniser, performing the rotational speed synchronisation by means of both the electric traction motor and the mechanical synchroniser.

Methods and systems are provided for controlling and diagnosing a mechanical vehicle component. In one example, a method may include determining a vehicle speed and a plurality of clutch position settings at a diagnostic controller, and identifying unauthorized conditions based on these determinations. Further, the diagnostic controller may trigger an active fault state of the mechanical vehicle component in order to avoid unauthorized conditions that may lead to unwanted or unanticipated changes in vehicle motion.

Methods and systems are provided for controlling and diagnosing a mechanical vehicle component. In one example, a method may include determining a vehicle speed and a plurality of clutch position settings at a diagnostic controller, and identifying unauthorized conditions based on these determinations. Further, the diagnostic controller may trigger an active fault state of the mechanical vehicle component in order to avoid unauthorized conditions that may lead to unwanted or unanticipated changes in vehicle motion.

A parking release monitoring device for an automatic transmission vehicle is proposed. The device includes: a receiver sensing an output signal of a shift lever; a determiner determining a target gear stage in accordance with the output signal of the shift lever; a driver transmitting a control signal to a parking solenoid to engage a parking sprag and applying a driving current to a clutch control solenoid to engage a clutch and prevent rolling of the vehicle when the determined target gear stage is a P-gear stage; and a detector measuring the intensity of the driving current applied to the clutch control solenoid, in which the determiner receives intensity information of the driving current applied to the clutch control solenoid from the detector and compares the received intensity information of the driving current with the output signal of the shift lever, thereby determining whether parking release has occurred.