A method for preventing an incorrect learning of a clutch torque of a transmission of a vehicle may include a controller estimating an engine-based clutch torque estimated based on an engine torque; the controller estimating a wheel-based clutch torque estimated based on a driveshaft torsional torque; the controller determining a torque error, which is a difference between the engine-based clutch torque and the wheel-based clutch torque: the controller allowing a learning of the clutch torque when the torque error is equal to or less than a predetermined reference torque; and the controller prohibiting the learning of the clutch torque when the torque error is greater than the predetermined reference torque.

A method for preventing an incorrect learning of a clutch torque of a transmission of a vehicle may include a controller estimating an engine-based clutch torque estimated based on an engine torque; the controller estimating a wheel-based clutch torque estimated based on a driveshaft torsional torque; the controller determining a torque error, which is a difference between the engine-based clutch torque and the wheel-based clutch torque: the controller allowing a learning of the clutch torque when the torque error is equal to or less than a predetermined reference torque; and the controller prohibiting the learning of the clutch torque when the torque error is greater than the predetermined reference torque.

A flexible drive shaft test arrangement includes a drive end piece arranged along a rotation axis, a driven end piece axially offset from the drive end piece along the rotation axis, and a shell. The shell connects the drive end piece to the driven end piece. The drive end piece end is offset in rotation about the driven end piece to internally load a flexible drive shaft disposed within the shell with torsion. Test stands and methods for testing flexible drive shafts are also disclosed.

A flexible drive shaft test arrangement includes a drive end piece arranged along a rotation axis, a driven end piece axially offset from the drive end piece along the rotation axis, and a shell. The shell connects the drive end piece to the driven end piece. The drive end piece end is offset in rotation about the driven end piece to internally load a flexible drive shaft disposed within the shell with torsion. Test stands and methods for testing flexible drive shafts are also disclosed.

A method for determining reference values of a sensor is provided. The reference values correspond to a disengaged operating condition or to an engaged operating condition of a form-locking shift element (A, F). With the aid of the sensor, at least one operating parameter of the shift element (A, F) determinable during a disengagement and during an engagement of the shift element (A, F). A torque, an actuation force of the shift element (A, F), and a differential speed between shift-element halves of the shift element (A, F) are varied during the determination of the reference values of the sensor in such that the form-locking shift element (A, F) is transferred into the disengaged operating condition or into the engaged operating condition.

The system and method determines the torque applied to a rotating shaft by a load. A first sensor detects rotation of a first wheel and a second sensor detects rotation of a second wheel. A third sensor is proximate to the first sensor. A processor determines: 1) a magnitude of a phase angle (.sub.A) based on the first and second sensors and having an unknown sign; 2) a magnitude of a phase angle (.sub.B) based on the second and third sensors and having an unknown sign; and 3) a magnitude of a phase angle (.sub.C) based on the first and third sensors and having a known sign. The processor determines a sign of the phase angle (.sub.A) based on the values of the phase angles (.sub.C) and (.sub.C) and determines a torque value from the load applied to the shaft at least in part based on the magnitude and sign of the phase angle (.sub.A).

A transmission system includes a transmission, first and second composite sensors, and a controller. The transmission has a clutch switchable between an engaged state and a disengaged state, a first shaft disposed on an input side of the clutch, and a second shaft disposed on an output side of the clutch. The first and second composite sensors detect rotation speeds and rotation phases of the first and second shafts, respectively. The controller acquires a load torque applied to the transmission. When the clutch is switched from the disengaged state to the engaged state, the controller derives a phase difference between the rotation phase of the first shaft detected by the first composite sensor and the rotation phase of the second shaft detected by the second composite sensor based on the time when the clutch has stopped slipping. The controller acquires the load torque based on the derived phase difference.

A transmission system includes a transmission, first and second composite sensors, and a controller. The transmission has a clutch switchable between an engaged state and a disengaged state, a first shaft disposed on an input side of the clutch, and a second shaft disposed on an output side of the clutch. The first and second composite sensors detect rotation speeds and rotation phases of the first and second shafts, respectively. The controller acquires a load torque applied to the transmission. When the clutch is switched from the disengaged state to the engaged state, the controller derives a phase difference between the rotation phase of the first shaft detected by the first composite sensor and the rotation phase of the second shaft detected by the second composite sensor based on the time when the clutch has stopped slipping. The controller acquires the load torque based on the derived phase difference.

A torque monitoring system includes a rotatable measurement interface and a stationary data receiver. The measurement interface is configured to be attached to a rotatable shaft. The measurement interface includes a strain gauge, a processor, and a near field communication (NFC) transceiver coil. The stationary data receiver is stationary with respect to the rotating shaft. The stationary data receiver includes a processor and an NFC transceiver coil. The rotatable measurement interface receives operating power via its NFC transceiver coil that is derived from a radio signal wirelessly transmitted by the NFC transceiver coil in the stationary data receiver. The processor in the rotatable measurement interface is configured to receive strain gauge signals from the strain gauge indicative of torque on the rotatable shaft and wirelessly transmit digital data indicative of the strain gauge signals through the NFC transceiver coils to the processor in the stationary data receiver.

A torque monitoring system includes a rotatable measurement interface and a stationary data receiver. The measurement interface is configured to be attached to a rotatable shaft. The measurement interface includes a strain gauge, a processor, and a near field communication (NFC) transceiver coil. The stationary data receiver is stationary with respect to the rotating shaft. The stationary data receiver includes a processor and an NFC transceiver coil. The rotatable measurement interface receives operating power via its NFC transceiver coil that is derived from a radio signal wirelessly transmitted by the NFC transceiver coil in the stationary data receiver. The processor in the rotatable measurement interface is configured to receive strain gauge signals from the strain gauge indicative of torque on the rotatable shaft and wirelessly transmit digital data indicative of the strain gauge signals through the NFC transceiver coils to the processor in the stationary data receiver.