초록 ▼

A system and method for automatically running a vehicle at a desired cruising speed in which in order to properly control an opening angle of a throttle valve of a vehicular engine, the opening angle of the throttle valve is feedforward controlled. In the feedforward control, a wheel force of the ve

A system and method for automatically running a vehicle at a desired cruising speed in which in order to properly control an opening angle of a throttle valve of a vehicular engine, the opening angle of the throttle valve is feedforward controlled. In the feedforward control, a wheel force of the vehicle is derived by storing an instantaneous angular displacement of the throttle valve for each period of controlling the angular displacement of the throttle valve, weighting transient characteristics of a transmission torque in a power train of the vehicle including dead times and first order lag to the stored instantaneous angular displacement of the throttle valve to derive each wheel force for the period of controlling the angular displacement of the throttle valve, and averaging each wheel force for each period of deriving a change rate of the vehicle speed to derive the wheel force. The wheel force is used to derive a running resistance of the vehicle based on deriving a target angular displacement of the throttle valve to maintain the vehicle speed at the cruising speed.

대표청구항 ▼

A system for automatically running a vehicle at a desired cruising speed, comprising: (a) first means for deriving a vehicle speed; (b) second means for deriving a change rate of the vehicle speed for each first predetermined period of time; (c) third means through which the vehicle speed at which t

A system for automatically running a vehicle at a desired cruising speed, comprising: (a) first means for deriving a vehicle speed; (b) second means for deriving a change rate of the vehicle speed for each first predetermined period of time; (c) third means through which the vehicle speed at which the vehicle runs is set by a driver as the desired cruising speed; (d) fourth means for deriving an instantaneous angular displacement of a throttle valve installed in a vehicular engine (e) fifth means for deriving a change of a transmission torque of a power train in the vehicle with respect to a change in the instantaneous angular displacement of the throttle valve for each second predetermined period; (f) sixth means for deriving an average wheel force for each first predetermined period derived on the basis of the change of the transmission torque by the fifth means for each second predetermined period and estimating a running resistance of the vehicle on the basis of the change rate of the vehicle speed derived by the second means and said average wheel force; (g) seventh means for deriving a target angular displacement of the throttle valve to maintain the vehicle speed at the cruising speed set by the third means on the basis of the estimated running resistance derived by the sixth means; (h) eighth means for producing and outputting a vehicle speed control command to maintain the vehicle speed at the cruising speed on the basis of an error between the vehicle speed and cruising speed, said change rate of the vehicle speed, and said error between the instantaneous angular displacement and said target angular displacement of the throttle valve; and (i) ninth means responsive to the vehicle speed control command for actuating the throttle valve to displace the throttle valve toward the target angular displacement.