System and method for automatically controlling a vehicle speed to a desired cruising speed

摘要

A system and method for automatically controlling a vehicle speed to a desired cruising speed in which after a vehicular engine is set in an acceleration state for the vehicle through an actuator under an acceleration control of the vehicle speed in response to a command operation of an acceleration switch, the vehicular engine is set so that the vehicle speed is reduced and arrives at a set cruising speed at a time of a reset of the command operation of the acceleration switch. At this time, in the vehicle speed controlling system and method, a duration in which the vehicle speed is one abruptly reduced is calculated on the basis of a control duration for which the vehicle speed is in the acceleration state under the acceleration control so that the vehicle speed is smoothly reduced and reaches the set cruising speed. The acceleration state of the vehicle speed is such that the actuator actuates a throttle valve to angularly displace toward an open direction so that the rate of increase in the vehicle speed with respect to time (i.e., acceleration value) is increased to match with a predetermined rate.