A vehicle includes a transmission, an engine, a disconnect clutch, an inertial measurement unit, and a controller. The transmission has an input shaft and an output shaft. The engine is configured to generate and deliver torque to the input shaft. The disconnect clutch is configured to connect and disconnect the engine from the input shaft. The disconnect clutch is also configured to crank the engine during an engine start. The inertial measurement unit is configured to measure inertial forces exerted onto the vehicle. The controller is programmed to, in response to a command to adjust a torque of the disconnect clutch to a desired value that is derived from the inertial forces and a vehicle velocity, drive the clutch actuator pressure to a value that corresponds to the desired value.

A method sets a predefined position of a clutch actuator comprising a friction spring element. An activation path of the clutch actuator that actuates the clutch is predefined by a coupling torque via a coupling characteristic curve, wherein the predefined position (zo, zu) to be assumed by the clutch actuator is set by a closed-loop controller. To enable the predefined position of the clutch actuator to be set precisely without using additional energy, the predefined position (zo, zu) is corrected by a turning back value (ro, ru) of the friction spring element and the corrected position (zo+ro; zu−ru) of the clutch actuator is approached by the closed-loop controller. After reaching the corrected position (zo+ro; zu−ru) the closed-loop controller is switched off by dissipating the potential energy stored in the friction spring element.

A method for determining a kiss point is disclosed. A drive unit having one or more motors with a motor output shaft is provided. One or more actuation profiles are ran and an amount of motor current and motor shaft position data is measured. The data measured is filtered and one or more motor current vs. motor shaft position plots having one or more curves with a high force and high current region are generated. A derivative is calculated over the curves and a slope of the high force and high current region is determined. A relative slope threshold is determined by multiplying the slopes by a predetermined percentage. One or more lines having a slope substantially equal to the relative slope threshold are plotted. The kiss point is determined based on the position of the motor shaft where the derivative of the curves equals the slope of the lines plotted.

A method sets a predefined position of a clutch actuator comprising a friction spring element. An activation path of the clutch actuator that actuates the clutch is predefined by a coupling torque via a coupling characteristic curve, wherein the predefined position (zo, zu) to be assumed by the clutch actuator is set by a closed-loop controller. To enable the predefined position of the clutch actuator to be set precisely without using additional energy, the predefined position (zo, zu) is corrected by a turning back value (ro, ru) of the friction spring element and the corrected position (zo+ro; zu−ru) of the clutch actuator is approached by the closed-loop controller. After reaching the corrected position (zo+ro; zu−ru) the closed-loop controller is switched off by dissipating the potential energy stored in the friction spring element.

A vehicle control apparatus includes (a) a clutch control portion configured to output a hydraulic-pressure command value for supplying a hydraulic pressure to a clutch actuator of a clutch disposed between an engine and an electric motor, when the engine is to be started by being cranked by the electric motor, and (b) a learning control portion configured to execute a plurality of leanings for correcting a relationship representing a correlation between the hydraulic pressure and the hydraulic-pressure command value, wherein at least one of the leanings is a higher priority learning, and at least one of the leanings is a lower priority learning. The learning control portion is configured, when the higher priority learning is in an unconverged state, to cause a degree of reflection of a learning result of the lower priority learning to be lower, than when the higher priority learning is in a converged state.

A method of setting a clutch control reference value may make it possible to more accurately learn the VKP of a hydraulic multi-plate clutch controlled by a solenoid valve, improving the accuracy of clutch control, and furthermore, to improve the quality of shifting a vehicle by the precise control of a transmission provided with such a clutch.

A method of setting a clutch control reference value may make it possible to more accurately learn the VKP of a hydraulic multi-plate clutch controlled by a solenoid valve, improving the accuracy of clutch control, and furthermore, to improve the quality of shifting a vehicle by the precise control of a transmission provided with such a clutch.

A shift control method of a transmission including an electric oil pump (EOP) directly connected to a friction clutch for a vehicle may include: when a shift is initiated, setting, by a controller, a predetermined first target RPM for controlling the EOP; determining, by the controller, a target current based on the first target RPM; maintaining, by the controller, the first target RPM until an EOP driving current reaches the target current; when the EOP driving current is greater than or equal to the target current, linearly reducing, by the controller, an RPM of the EOP from a predetermined second target RPM to a third target RPM; and increasing, by the controller, an EOP driving power to increase a friction force of the friction clutch such that a slip of the friction clutch is smaller than a predetermined reference slip.

A shift control method of a transmission including an electric oil pump (EOP) directly connected to a friction clutch for a vehicle may include: when a shift is initiated, setting, by a controller, a predetermined first target RPM for controlling the EOP; determining, by the controller, a target current based on the first target RPM; maintaining, by the controller, the first target RPM until an EOP driving current reaches the target current; when the EOP driving current is greater than or equal to the target current, linearly reducing, by the controller, an RPM of the EOP from a predetermined second target RPM to a third target RPM; and increasing, by the controller, an EOP driving power to increase a friction force of the friction clutch such that a slip of the friction clutch is smaller than a predetermined reference slip.

A method for adjusting a clutch characteristic curve, including obtaining a torque-stroke learning value for adjusting the clutch characteristic curve, calculating a convergence value for each control point of the clutch characteristic curve, calculating a difference value between the convergence value and a characteristic curve value for each control point, and determining a new characteristic curve value of each control point according to whether a maximum value of the calculated difference values exceeds a preset reference value.