Launch control method for vehicle

A vehicle launch control method comprising:

• (i) increasing clutch torque of a clutch of a vehicle according to a decrease in braking pressure when a launch control operation is initiated;
• (ii) maintaining the clutch torque at a current torque level for a first reference duration when the clutch torque reaches or exceeds a first reference torque level;
• (iii) after a lapse of the first reference duration, when a wheel slip ratio exceeds a first reference slip ratio, reducing the clutch torque within a range which is lower than the first reference torque level and is equal to or greater than a second reference torque level which is lower than the first reference torque level;
• (iv) when the wheel slip ratio is equal to or less than a second reference slip ratio which is less than the first reference slip ratio or when a second reference duration elapses after the clutch torque reaches or exceeds the first reference torque level, increasing the clutch torque until the clutch torque reaches a third reference torque level which is higher than the first reference torque level;
• and
• (v) stopping the launch control operation when a state in which a clutch slip remains less than a predetermined critical synchronous slip is maintained for a predetermined critical synchronization duration or longer than the predetermined critical synchronization duration,
• wherein after the step (iv), when the clutch slip is equal to or less than a first reference clutch slip, an average speed of driven wheels of the vehicle is equal to or greater than a first reference speed, and the wheel slip ratio is equal to or less than a third reference wheel slip ratio, a step of increasing the clutch torque toward a fourth reference torque level is performed.

A vehicle comprising:

• a transmission;
• an engine, wherein an output power of the engine undergoes an upshift or a downshift through the transmission;
• a clutch mounted between the engine and the transmission;
• and
• a controller electrically connected to the transmission and the clutch,
• wherein the controller is configured for:
• increasing clutch torque of the clutch according to a decrease in braking pressure when a launch control operation of the vehicle is initiated;
• maintaining the clutch torque at a current torque level for a first reference duration when the controller determines that the clutch torque reaches or exceeds a first reference torque level;
• after a lapse of the first reference duration, when a wheel slip ratio exceeds a first reference slip ratio, reducing the clutch torque in a range which is lower than the first reference torque level and is equal to or greater than a second reference torque level which is lower than the first reference torque level;
• when the wheel slip ratio is equal to or less than a second reference slip ratio which is less than the first reference slip ratio or when a second reference duration elapses after the clutch torque reaches or exceeds the first reference torque level, increasing the clutch torque until the clutch torque reaches a third reference torque level which is higher than the first reference torque level;
• and
• stopping the launch control operation when the controller determines that a state in which a clutch slip remains less than a predetermined critical synchronous slip is maintained for a predetermined critical synchronization duration or longer than the predetermined critical synchronization duration.