Abstract: A system and method for automatically controlling a vehicle speed to a desired cruise speed are disclosed in which a target opening angle of an engine throttle valve through which the vehicle can maintain a set cruise speed is derived in accordance with a prepared non-linear characteristic table and an opening angle of the throttle valve is controlled so that a detected vehicle speed coincides with the set cruise speed and a detected opening angle of the throttle valve coincides with the target opening angle. In addition, when the detected vehicle speed and detected opening angle are substantially constant for a predetermined time due to the vehicle being run on a flat road, average values of both detected vehicle speed and detected opening angle are derived and the above-described non-linear characteristic is corrected using both average values.

Abstract: A system and method for automatically controlling a vehicle speed to a desired cruise speed are disclosed in which in addition to a control unit and a throttle actuator through which an opening angle of an engine throttle valve is adjusted so that the vehicle speed detected by a vehicle speed sensor coincides with a target cruise speed set by a vehicle driver through a set switch, a vehicle speed determining circuit is provided for determining whether the vehicle speed detected by the vehicle speed sensor exceeds a lowest speed limit above which the cruse control by the control unit and throttle actuator becomes effective. When the vehicle speed is below the lowest speed limit, the power supply to the throttle actuator is interrupted so that the cruise control by means of the throttle actuator is cancelled.

Abstract: A system and method for automatically controlling a vehicle speed to a desired cruise speed includes an inhibit switch connected in parallel to a line between a power supply and a main self hold power supply switch (self-hold type) of an automatic cruise controlling system. When the vehicle speed is below a predetermined value, the inhibit switch is open so that the automatic cruise speed controlling system cannot receive power via the main, switch. Thus, wasteful comsumption of power is reduced.

Abstract: A cruise control system for an automotive vehicle with a manual or automatic transmission, includes an inhibition circuit. The inhibiting circuit blocks communication between a power supply and an actuator and/or a controller when the manual transmission is set in a predetermined gear or when the automatic transmission is set in a driving range other than the drive range, so as to inhibit the controller from operating in the cruise control mode. When the vehicle is provided with an automatic transmission which is selectively set in first, second, third or fourth gear while the shift lever is set in the drive range position, the cruise control system includes a first inhibiting circuit which blocks the communication when the shift lever is set in a position other than the drive range position, and a second inhibiting circuit which blocks the communication when the automatic transmission is set in either the first or second range while the shift lever is set in the drive range position.

Abstract: A system for automatically controlling vehicle speed calculates the relative speed between the subject vehicle and another preceding vehicle on the basis of the intervehicle distance detected by an intervehicle distance detector. One of a number of relative speed values derived with reference to different sampling periods is selected according to the magnitude of one of the relative speed values so that a highly accurate and fast responsive system for controlling the vehicle speed can be achieved on the basis of the vehicle speed, intervehicle distance, and selected relative speed.

Abstract: A System and method for automatically controlling a vehicle speed to a desired cruise speed are disclosed in which a control unit determines whether a control mode is a steady state mode in which the vehicle cruises at a set target vehicle speed or a transient state in which the target vehicle speed is transiently changed on the basis of input data of the actual vehicle speed, set target vehicle speed, an actual opening angle of an engine throttle valve, and a target opening angle of an engine throttle valve determined on the basis of a running resistance of the vehicle. In the steady state mode, the control unit controls a throttle actuator so that the target opening angle of the throttle valve coincides with the actual vehicle speed and actual vehicle speed is matched with the target vehicle speed.

Abstract: A system and method for automatically controlling a vehicle speed to a desired cruise speed are disclosed in which a vehicle speed sensor which output an analog quantity corresponding to a current vehicle speed is provided, a vehicle speed determining circuit which derives the current vehicle speed on the basis of the analog quantity derived from the vehicle speed sensor and determines whether the derived current vehicle speed is below a predetermined speed above which the cruise speed control run is appropriate is furthermore provided independently of a control unit of the system. When the vehicle speed determining circuit outputs a determination signal indicating that the current vehicle speed is below the predetermined speed and the control unit outputs a predetermined control command signal, a power supply line connected to a throttle valve actuator is, at first, interrupted. Then, the power supply to the control unit is interrupted.

Abstract: A system and method for automatically controlling a vehicle speed to a desired cruise speed are disclosed in which whether a microcomputer of a control unit is enabled to perform a cruise speed control is determined on the basis of a plurality of determining factors and a power supply of a throttle actuator for actuating an engine throttle valve so as to adjust an opening angle of the throttle valve is enabled only when all of the determining factors satisfy a condition of enabling the cruise speed control via the actuator and is disabled when at least one of the determining factors does not satisfy the condition.

Abstract: A system and method for automatically controlling a vehicle speed to a desired cruising speed are disclosed in which such a control is inhibited that the opening angle is adjusted toward a prohibiting range in which an engine output torque becomes substantially constant even if the opening angle of the throttle valve is increased more than necessary. At this time, the opening angle is adjusted to a predetermined limit angle (for example, 40 degrees) and a transmission gear position is controlled depending on a difference between an instantaneous vehicle speed and a target vehicle speed. Therefore, unnecessary opening of the throttle valve exceeding the predetermined limit beyond which little increase in the engine output torque occurs can be avoided. In addition, the throttle valve can immediately be controlled from the predetermined limit to a target opening angle at which the vehicle speed can be maintained at the target vehicle speed.

Abstract: A system and method for automatically controlling a vehicle speed to a desired cruise speed are disclosed in which when a vehicular running resistance is derived on the basis of an engine torque and change rate of the vehicle speed with time, the engine torque being derived on the basis of an engine revolutional speed and engine load, a predetermined factor determining the running resistance is derived on the basis of the running resistance. In addition, an absolute value of a difference of the predetermined factor from a previous predetermined factor derived one predetermined calculation period before is compared with a predetermined threshold value, a zero engine driving force command is outputted to an actuator of an engine driving force adjustng mechanism so that the engine driving force adjusting mechanism is actuated to zero the engine driving force to recover gripping forces of drive wheels when the absolute value of the difference exceeds the predetermined threshold value.

Abstract: A system and method for automatically controlling a vehicle speed to a desired cruise speed are disclosed in which an opening angle of a first throttle valve is adjusted so that the vehicle speed coincides with a target vehicle speed at which the vehicle cruises. The cruise control for the vehicle speed through the first throttle valve is inhibited when an occurrence of a slip on a drive wheel is detected and a traction control by means of a traction controlling system such that a driving force of the vehicle is reduced through a second throttle valve disposed in series with the first throttle valve in an engine intake air passage is executed so that an effective traction control can be achieved without interference of both systems when the vehicle enters on a road surface having a very low friction coefficient.

Abstract: A system and method for automatically controlling a vehicle speed to a desired cruise speed are disclosed in which whether after any one of command and release signals is outputted from the corresponding set/cruise, acceleration, resume, brake, clutch, and cancel switches, a control unit outputs a corresponding receipt signal via a corresponding output port is determined, whether the contents of the control command signals presently outputting through the respective control valves are equal to inverted levels at the respective control valve is determined, and a power supply to control valves for adjusting an operating variable of an engine driving force adjusting mechanism and the control unit is interrupted when at least one of the results of determinations indicates a negative result.

Abstract: A system and method for automatically controlling a vehicle speed to a desired cruising speed applicable to vehicles in which a basic manipulated variable corresponding, for instance, to an operation time of either of acceleration or deceleration valve in an actuator for actuating an engine throttle valve of a vehicle in which the system is mounted toward the acceleration or deceleration direction which is derived on the basis of the vehicle speed and target cruising speed so that the vehicle speed coincides with the desired target cruising speed is corrected according to a transfer function of a response to the opening angle of the throttle valve to the manipulated variable. The response of the throttle valve to a change in the manipulated variable is measured and the transfer function is computed on the basis of the measured response to compensate for vehicle variations and aging effects.

Abstract: A system and method for automatically running a vehicle at a desired cruising speed, in which a running resistance of the vehicle is always derived, a target opening angle of a throttle valve of a vehicular engine which can run the vehicle at a desired constant acceleration and/or at the desired cruise running speed is derived under the derived running resistance, and the opening angle of the throttle valve is controlled in a feedforward control mode so as to coincide with the target opening angle. The automatic cruise running system and method can achieve no variation of vehicle speed when the vehicle runs on a rugged road.

Abstract: 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.

Abstract: A method and system for detecting a presence of a preceding vehicle moving in a front detection area of a controlled vehicle. In the method and system thereof, a plurality of laser or other kinds of beams are transmitted to any object present in the front detection area and the plurality of reflected beams are received so that the respective distances to the reflecting objects are measured on the basis of the propagation delay times between the transmission and reception of the beams.

Abstract: A system for detecting the presence or absence of a vehicle in front of a subject vehicle and method therefor, wherein a plurality of wave transmitters transmit distance measuring media such as laser beams or electromagnetic waves over a front detection area toward which the distance measuring media are transmitted in mutually different directions and through respectively predetermined angles with respect to a longitudinal axis of the subject vehicle. In the detecting system and method, the presence of the preceding vehicle is determined on the basis of propagation delay between the times at which at least one of the waves is transmitted and at which the reflected waves are received. The lateral progress of the vehicle in front of the subject vehicle from detection area to detection area is monitored to maintain contact with the detected vehicle even around curves or during steering adjustments.

Abstract: An apparatus and method for measuring the distance to a desired light-reflecting object capable of recognizes erroneous measurements due to the presence of light-reflecting particle suspended in the air, wherein the range of intensity of reflected light achievable by air-borne particles is previously stored and output of the distance to the light-reflecting object is inhibited when the intensity of reflected light falls within the above-described range of intensity of reflected light.

Abstract: A system and method for detecting a distance from a vehicle to an obstacle in front of the vehicle and controlling the vehicle according to changes in the distance thereof holds the vehicle speed constant upon recognition of the fact that the detected obstacle is a plurality of regularly spaced, stationary objects disposed along a side of a curved road and otherwise the vehicle speed is controlled on the basis of the distance between the vehicle and detected obstacles such as other vehicles moving in front of the vehicle or obstacles resting on the road as the vehicle moves through a curve.

Abstract: In a system and method for automatically controlling a vehicle's speed, the rate of change of the inter-vehicle distance per predetermined unit of time is calculated from the detected inter-vehicle distance between the controlled vehicle and a preceding vehicle, a basic safe inter-vehicle distance is corrected according to the calculated rate of change of the inter-vehicle distance per predetermined time, and the vehicle speed is controlled according to the difference between the corrected safe inter-vehicle distance and the detected inter-vehicle distance.