A method for controlling power takeoff (PTO) clutch engagement includes determining an output clutch speed, adjusting a clutch current at a predetermined rate, estimating an inertial load of a PTO implement and adjusting the clutch current for one or more times at a time interval, and selecting a clutch control algorithm configured for the inertial load of the PTO implement.

A method for operating a vehicle drivetrain (1) includes decoupling, in the presence of a demand for realizing a sailing operating state of the vehicle drivetrain (1) during which a drive machine (2) is active and the power flow between the drive machine (2) and a drive output (3) is disconnected in a gearbox (4), the active drive machine (2) from the drive output (3) by opening of one of a plurality of shift elements (A to F) that is held in a closed operating state in order to realize the operating state present before the demand for decoupling of the active drive machine (2). The method also includes then actuating the plurality of shift elements (A to F) in a manner dependent on the present operating state profile of the vehicle drivetrain (1) and with the active drive machine (2) decoupled from the drive output (3).

A dual clutch automatic transmission includes a one-way clutch provided in a driving force transmission path that establishes a first certain gear ratio in a first set of gear ratios. A driving transmission direction of the one-way clutch is set such that a rotation inputted from a wheel side to an output member in a predetermined rotational direction is transmitted to the input shaft. The predetermined rotational direction corresponds to a backward movement of a vehicle. If an off-gear operation cannot be performed for a transmission gear with interlock, the driving force of the driving source is input to the input shaft to enable the off-gear operation.

A method for operating a motor vehicle having a transmission (1), the method including closing a first number of shift elements and opening a second number of shift elements in each selected, force locking gear ratio of the transmission (1); closing one shift element less, and therefore opening one shift element more than in a selected, force locking gear ratio when a transmission (1) is not force locking in the sailing mode; adjusting the respectively closed and opened shift elements as a function of at least one operating condition of the motor vehicle in the sailing mode; and checking, at least on the basis of the rotational speed of the transmission input shaft (2), whether a previously closed, positively locking shift element (A, F) to be opened is actually opened in the sailing mode during adjusting of the respectively closed and opened shift elements.

During a transmission upshift, a torque capacity of an off-going clutch is maintained at a non-zero state during the transition from the torque phase to the inertia phase and throughout a substantial portion of the inertia phase. This permits the inertia phase to be completed faster without an unacceptable increase in output torque during the torque phase. Monotonically reducing the off-going clutch torque and using feedback from an output torque sensor enable sufficiently precise control of the off-going clutch torque capacity during this interval.

A method is provided for controlling the position of a gearbox actuator in charge of engaging a ratio at the end of a preliminary phase of synchronizing two shafts of the gearbox via a torque-driven traction machine to bring the speed difference of the two shafts within a range enabling the mechanical coupling thereof. The method ensures that the speed measured on one of the two shafts converges with a speed observed as a function of the inertia value observed on this shaft relative to the value expected as a function of the gearbox actuator, and of an estimation of the machine torque.

A method for controlling PTO clutch engagement includes determining a first change in clutch speed based on an inertial load of a PTO implement. The method also includes determining a second change in clutch speed based on a threshold amount of energy of a PTO clutch. The method further includes determining a third change in clutch speed between the first change in clutch speed and the second change in clutch speed. The method also includes adjusting a clutch current based on the third change in clutch speed.

An agricultural vehicle includes an engine, a transmission driven by the engine, and a controller. The controller, in operation, adjusts a gear ratio of the transmission using an algorithm. The algorithm, in operation, performs the following steps: reduce a torque capacity of a first offgoing clutch of the transmission to a first torque target, reduce the torque capacity of the first offgoing clutch to a second torque target while adjusting the torque capacity of a first oncoming clutch of the transmission to a third torque target, such that the gear ratio of the transmission is modified in a first direction, and increase the torque capacity of the first oncoming clutch to a desired torque capacity.

A system includes an engine, a transmission driven by the engine, and a controller. The controller is configured to receive a speed input, receive feedback indicative of a load of the engine at a current engine speed, compare the load to a predetermined load threshold at the current engine speed, determine an expected engine speed based at least on the current engine speed, a current gear ratio, and an expected gear ratio, determine an estimated engine power at the expected engine speed and a current engine power at the current engine speed, and command a gear downshift when the load is greater than or equal to the predetermined load threshold and when the estimated engine power is greater than the current engine power.

During a transmission upshift, a torque capacity of an off-going clutch is maintained at a non-zero state during the transition from the torque phase to the inertia phase and throughout a substantial portion of the inertia phase. This permits the inertia phase to be completed faster without an unacceptable increase in output torque during the torque phase. Monotonically reducing the off-going clutch torque and using feedback from an output torque sensor enable sufficiently precise control of the off-going clutch torque capacity during this interval.