The present invention is a powertrain for a hybrid vehicle, comprising a driving/receiving machine (20), a thermal engine (10) and engine shaft (12), a speed variation device (14) including an engine epicyclic gear train (24) with a sun gear (34) and a crown (42) which are each connected to the engine shaft (12) by an engine controlled coupling (26, 28) and to a fixed part (40) of the powertrain by a one-way automatic coupling (30, 32). A planet gear carrier (46) and a machine epicyclic gear train (60) are arranged on a shaft (62) substantially parallel to engine shaft (12). The planet gear carrier comprises a sun gear (64), a crown (72), a planet gear carrier (68) and an epicyclic gear train controlled coupling (88). The speed variation device (14) comprises a device (94) for connecting/disconnecting electric machine (20) with machine epicyclic gear train (60).

A power system includes an engine; a sensor to determine an engine speed; and a transmission. The transmission includes an input element configured to receive the power from the engine as input torque; an output element configured to provide at least a portion the power from the engine as output torque; and a clutch arrangement to transform the input torque into output torque. The clutch arrangement includes at least one clutch selectively positionable between a fully engaged state, a partially engaged state in which a portion of the input torque is transformed into the output torque, and a fully disengaged state. A controller is coupled to the at least one clutch and configured to generate clutch commands based at least in part on the engine speed to position the at least one clutch into the fully engaged state, the partially engaged state, or the fully disengaged state.

A method for carrying out a shifting operation in a sequential manual transmission, in particular a shifting claw transmission, is provided. During the shifting operation, a maximum clutch torque that can be transmitted by a clutch arranged between an engine and a transmission input shaft is automatically reduced without completely disengaging the clutch, and a rider-required drive torque is maintained in a manner which reduces undesired jerking movement of the vehicle due to sudden full clutch actuation.

A shift change practice device capable of improving the effect of learning a shift change operation is provided. The shift change practice device includes: an optimum speed calculation unit that calculates an optimum value or an optimum range of an engine revolution speed in the event of a shift change; a revolution speed comparison unit that determines whether or not a detected revolution speed that is a detected value of the engine revolution speed is equal to the optimum value or whether or not the detected revolution speed is included in the optimum range, in a state where a clutch is disconnected; and a notification instruction unit that instructs a notification device to give a predetermined notification to a driver when the detected revolution speed is equal to the optimum value or the detected revolution speed is included in the optimum range, in the state where the clutch is disconnected.

A method for carrying out a shifting operation in a sequential manual transmission, in particular a shifting claw transmission, is provided. During the shifting operation, a maximum clutch torque that can be transmitted by a clutch arranged between an engine and a transmission input shaft is automatically reduced without completely disengaging the clutch, and a rider-required drive torque is maintained in a manner which reduces undesired jerking movement of the vehicle due to sudden full clutch actuation.

A method and system for operating a vehicle that includes a driveline disconnect clutch and a step-ratio transmission is described. In one example, the method includes shifting the step-ratio transmission to neutral and accelerating an engine to an expected input shaft speed of the step-ratio transmission via applying full output capacity of an electric machine to the engine.

A power system includes an engine; a sensor to determine an engine speed; and a transmission. The transmission includes an input element configured to receive the power from the engine as input torque; an output element configured to provide at least a portion the power from the engine as output torque; and a clutch arrangement to transform the input torque into output torque. The clutch arrangement includes at least one clutch selectively positionable between a fully engaged state, a partially engaged state in which a portion of the input torque is transformed into the output torque, and a fully disengaged state. A controller is coupled to the at least one clutch and configured to generate clutch commands based at least in part on the engine speed to position the at least one clutch into the fully engaged state, the partially engaged state, or the fully disengaged state.

A method and system for operating a vehicle that includes a driveline disconnect clutch and a step-ratio transmission is described. In one example, the method includes shifting the step-ratio transmission to neutral and accelerating an engine to an expected input shaft speed of the step-ratio transmission via applying full output capacity of an electric machine to the engine.

A method for determining and controlling engine speeds of a work vehicle during gear shifts may include controlling an operation of an engine and/or a transmission of a work vehicle so as to maintain the work vehicle operating at a requested speed, and determining a measured gear ratio for the transmission as a gear shift is occurring from a first gear ratio to a second gear ratio. The method may also include calculating a desired engine speed during the gear shift as a function of the requested speed and either the measured gear ratio or the second gear ratio. In addition, when the measured gear ratio differs from the first gear ratio by a predetermined threshold amount, the method may include controlling the engine speed based on the desired engine speed for a remainder of the gear shift from the first gear ratio to the second gear ratio.

A shift control method of a vehicle with a dual clutch transmission (DCT) may include: a first preparing step of, by a controller, controlling a torque of an N-th stage clutch to a predetermined minimum torque and increasing a torque of an N1-th stage clutch to a predetermined standby torque; a first handover step of releasing the torque of the N-th stage clutch and increasing the torque of the N1-th stage clutch; a gear changing step of releasing an N-th stage gear and then initiating an engagement of an N2-th stage gear; a synchronization maintaining step of maintaining a synchronized state by adjusting the torque of the N1-th stage clutch; a second preparing step of increasing the torque of the N2-th stage clutch to the standby torque; and a second handover step of releasing the torque of the N1-th clutch and increasing the torque of the N2-th stage clutch.