An automatic transmission includes a clutch device having a clutch hub, a clutch drum, a friction plate, a piston, and a hydraulic chamber. The clutch drum includes an outer-side cylindrical portion, a disc-shaped first radial portion extending radially inwardly, an axial portion extending axially from the first radial portion, and a disc-shaped second radial portion extending radially inwardly from the axial portion. The piston includes a pressing portion disposed between the first radial portion and the friction plate side, and a disc-shaped piston radial portion extending radially inwardly from the pressing portion. The hydraulic chamber is provided radially inwardly from the axial portion and on the non-friction-plate side of the piston radial portion. A comb-teeth portion is provided at a radially intermediate portion of the piston radial portion. The axial portion and the piston radial portion intersect with each other in a comb-teeth shape.

An output is calculated using, as an input, a measured value of a pump discharge pressure in a neural network having the pump discharge pressure as the input and a pump rotational speed as the output. A leakage degree of oil of the hydraulic circuit of a transmission is estimated based on a difference obtained by subtracting a measured value of the pump rotational speed from the calculated value of the output. Learning of the neural network is performed using, as teacher data, the measured values of the pump discharge pressure and the pump rotational speed in the transmission in which the leakage degree of oil is within an allowable range.

The present disclosure relates to a method for determining at least one shift parameter of a vehicle transmission (3), the vehicle transmission (3) comprising a first clutching device (8a) and a first speed ratio (9a); a second clutching device (8b) and a second speed ratio (9b); an input; and an output, wherein the input and the output of the transmission are connectable by the engaging first clutching device (8a) or the second clutching device (8b). The method comprises the steps: performing a shift by disengaging the first clutching device (8a) and/or engaging the second clutching device (8b), wherein the first clutching device (8a) stops transferring torque through the transmission at a first time point, wherein the second clutching device (8b) starts transferring torque through the transmission at a second time point, and determining the shift parameter at the first time point and/or at the second time point.

The present invention provides a shift control method implemented in a vehicle equipped with an automatic transmission for controlling an input shaft rotation speed to a target input shaft rotation speed during a shift. The method includes setting of a basic target synchronization rotation speed that is a basic target value of the input shaft rotation speed during the shift, and setting of a corrected target input shaft rotation speed as the target input shaft rotation speed when the shift is a downshift without a requirement for a driving force of the vehicle, The corrected target input shaft rotation speed is obtained by decreasingly correcting the basic target synchronization rotation speed. Further, a decreasing correction amount of the basic target synchronization rotation speed is set so as to become larger as a deceleration of the vehicle becomes larger.

A power generation controller of an aircraft includes a low-temperature start-up control section and a power generation control section. When it is determined that an oil temperature of a hydraulic actuator configured to change an operation position of a speed change element of a hydraulic transmission satisfies a predetermined low-temperature condition when starting up an aircraft engine, the low-temperature start-up control section sets a power generator to a power non-generating state and controls the hydraulic actuator such that the speed change element is positioned at an acceleration side of a median in a speed change range. When it is determined that the oil temperature satisfies a predetermined low-temperature start-up completion condition, the power generation control section sets the power generator to a power generating state and controls the hydraulic actuator in accordance with a rotational frequency of the aircraft engine.

The present invention provides a shift control method include: setting a basic target synchronization rotation speed that is a basic target value of the input shaft rotation speed during the shift; determining whether or not an accelerating intention is present when the shift is a downshift with a driving force requirement to the vehicle; when the accelerating intention is present, setting a first target input shaft rotation speed as the target input shaft rotation speed, the first target input shaft rotation speed being obtained by increasingly correcting the basic target synchronization rotation speed; and when the accelerating intention is not present, setting a second target input shaft rotation speed as the target input shaft rotation speed, the second target input shaft rotation speed being obtained by maintaining or decreasingly correcting the basic target synchronization rotation speed.

The present invention provides a shift control method include: setting a basic target synchronization rotation speed that is a basic target value of the input shaft rotation speed during the shift; determining whether or not an accelerating intention is present when the shift is a downshift with a driving force requirement to the vehicle; when the accelerating intention is present, setting a first target input shaft rotation speed as the target input shaft rotation speed, the first target input shaft rotation speed being obtained by increasingly correcting the basic target synchronization rotation speed; and when the accelerating intention is not present, setting a second target input shaft rotation speed as the target input shaft rotation speed, the second target input shaft rotation speed being obtained by maintaining or decreasingly correcting the basic target synchronization rotation speed.

The transmission controller is configured to, when the received range position signal indicates that the range position is switched from a travelling range to a neutral range during travelling, output an instruction to disengage all of friction elements that are in an engaged state in the travelling range, output an instruction to at least one friction element before the instruction to disengage all of the friction elements that are in the engaged state in the travelling range is output, confirm a change in a rotation speed of a transmission input shaft after the instruction to disengage is output to the at least one friction element, and when there is no change in the rotation speed, diagnose that the friction element instructed to be disengaged is in an erroneously engaged state in which the friction element is not able to be disengaged.

The transmission controller is configured to, when the received range position signal indicates that the range position is switched from a travelling range to a neutral range during travelling, output an instruction to disengage all of friction elements that are in an engaged state in the travelling range, output an instruction to at least one friction element before the instruction to disengage all of the friction elements that are in the engaged state in the travelling range is output, confirm a change in a rotation speed of a transmission input shaft after the instruction to disengage is output to the at least one friction element, and when there is no change in the rotation speed, diagnose that the friction element instructed to be disengaged is in an erroneously engaged state in which the friction element is not able to be disengaged.

A tidal current energy converter including an infinitely variable transmission (IVT) control system and a hybrid vertical axis wind (or water) turbine (VAWTs) apparatus. The hybrid VAWT apparatus includes a modified-Savonius (MS) rotor in the central region and a straight bladed H-type Darrieus rotor in the surrounding annular region. The IVT control system includes a nonlinear closed-loop control combined with an integral time-delay feedback control to adjust a speed ratio of the IVT. A speed ratio control for an IVT system involves a forward speed controller and/or a crank length controller for different speed ranges. The time-delay control is designed to reduce speed fluctuations of the output speed of an IVT with an accurate speed ratio. The speed ratio of an IVT with the disclosed control strategy can achieve an excellent tracking response for the desired constant output speed and reduce speed fluctuations of the output speed of an IVT by the time-delay feedback control.