A creep control method for a vehicle is disclosed. The creep control method includes a limit-setting step and a limit release step. In the limit-setting step, a controller compares a speed of an input shaft of a transmission with a predetermined creep reference speed, and, if it is determined that the speed of the input shaft is lower than the creep reference speed, a creep minimum torque of a clutch for controlling creep driving of the vehicle is set to be a predetermined lower limit torque, which is larger than 0. In the limit release step, if the controller determines that the speed of the input shaft is increased above the creep reference speed while the creep minimum torque is limited to the lower limit torque, the creep minimum torque is set to 0.

A creep control method for a vehicle is disclosed. The creep control method includes a limit-setting step and a limit release step. In the limit-setting step, a controller compares a speed of an input shaft of a transmission with a predetermined creep reference speed, and, if it is determined that the speed of the input shaft is lower than the creep reference speed, a creep minimum torque of a clutch for controlling creep driving of the vehicle is set to be a predetermined lower limit torque, which is larger than 0. In the limit release step, if the controller determines that the speed of the input shaft is increased above the creep reference speed while the creep minimum torque is limited to the lower limit torque, the creep minimum torque is set to 0.

The present disclosure relates to a method for controlling a lock-up clutch of an automatic transmission. The method includes: a detecting step of detecting, by a controller, a current signal applied to a solenoid valve of an engaging element when a gear change operation begins; and a first increasing control step of controlling, by the controller, an amount of current that is applied to a solenoid valve of a lock-up clutch during an initial fill time period when it is determined that the current signal is applied to the solenoid valve of the engaging element. In particular, the solenoid valve of the engaging element is used to form a gear stage, and the controller increases the amount of current to a predetermined level for a predetermined period of time.

The present disclosure relates to a method for controlling a lock-up clutch of an automatic transmission. The method includes: a detecting step of detecting, by a controller, a current signal applied to a solenoid valve of an engaging element when a gear change operation begins; and a first increasing control step of controlling, by the controller, an amount of current that is applied to a solenoid valve of a lock-up clutch during an initial fill time period when it is determined that the current signal is applied to the solenoid valve of the engaging element. In particular, the solenoid valve of the engaging element is used to form a gear stage, and the controller increases the amount of current to a predetermined level for a predetermined period of time.

A shifting control method for a vehicle with a Double Clutch Transmission (DCT), may include determining whether a manual range power-on up shift has been started, determining whether an actual shifting period has been started, when the manual range power-on up shift has been started, and applying additional predetermined compensation torque to basic torque applied to an engagement-side clutch, when the actual shifting period has been started.

A shifting control method for a vehicle with a Double Clutch Transmission (DCT), may include determining whether a manual range power-on up shift has been started, determining whether an actual shifting period has been started, when the manual range power-on up shift has been started, and applying additional predetermined compensation torque to basic torque applied to an engagement-side clutch, when the actual shifting period has been started.

Provided herein is a method for calibrating a clutch by searching for the minimum of a multi-dimensional surface including determining the error between a spline function and recorded data relating to clutch characteristics, creating a multi-dimensional surface corresponding to the error values, determining the minimum of the multi-dimensional surface using the steps of performing a Steepest Gradient & Direction determination step and conducting a Golden Section Search and Switch Direction Step to find a minimum that meets a predetermined closing condition. Additionally, provided herein is a computer-implemented system for calibrating the clutch.

Provided herein is a method for calibrating a clutch by searching for the minimum of a multi-dimensional surface including determining the error between a spline function and recorded data relating to clutch characteristics, creating a multi-dimensional surface corresponding to the error values, determining the minimum of the multi-dimensional surface using the steps of performing a Steepest Gradient & Direction determination step and conducting a Golden Section Search and Switch Direction Step to find a minimum that meets a predetermined closing condition. Additionally, provided herein is a computer-implemented system for calibrating the clutch.

In a clutch engagement control system for engagement and disengagement of transmission of a rotational force between a mainshaft and a countershaft, when clutch engagement control is executed based on the determination that rotational speeds of both the shafts agree with each other, even if unexpected variations in countershaft rotational speed result from torsion occurring downstream of the countershaft in a drive system and/or the like, smooth engagement control is implemented. A control value of countershaft rotational speed at each time is updated and managed. If a threshold value is exceeded by a difference between a countershaft rotational speed actual measured value and the preceding control value, the threshold value is added to the preceding value to obtain the control value. If the threshold value does not exceed the difference, the actual measured value at this time is set as a control value without any change.

In a clutch engagement control system for engagement and disengagement of transmission of a rotational force between a mainshaft and a countershaft, when clutch engagement control is executed based on the determination that rotational speeds of both the shafts agree with each other, even if unexpected variations in countershaft rotational speed result from torsion occurring downstream of the countershaft in a drive system and/or the like, smooth engagement control is implemented. A control value of countershaft rotational speed at each time is updated and managed. If a threshold value is exceeded by a difference between a countershaft rotational speed actual measured value and the preceding control value, the threshold value is added to the preceding value to obtain the control value. If the threshold value does not exceed the difference, the actual measured value at this time is set as a control value without any change.