Abstract: A driver regards a relative acceleration of a subject vehicle with respect to an object such as a preceding vehicle, an obstacle and the like as one having highest priority, and performs control such that deceleration is immediately started even if a relative velocity is small if the relative acceleration is large. Taking note of this point, the relative acceleration between the subject vehicle and the object is detected, and it is judged whether or not the subject vehicle and the object relatively approach each other at a relative acceleration not less than a predetermined value. A vehicle velocity is controlled such that the relative acceleration is not more than a predetermined target relative acceleration (for which a direction for approach is positive) when the subject vehicle and the object relatively approach each other at a relative acceleration not less than the predetermined value. Thus, the start of deceleration felt by the driver is adequate.

Abstract: The apparatus has a signal processor for determining the ground speed of a motor vehicle on the basis of the frequency of a wave transmitted from a transmitter and the frequency of the wave reflected by the ground surface and received by a receiver. The signal processor includes a relationship obtaining device for obtaining a relationship between an estimated vehicle speed obtained on the basis of the speed of a vehicle wheel, and a provisional speed determined on the basis of the frequencies of the transmitted and reflected waves, when the vehicle is in a steady running state in which the estimated vehicle speed accurately represents the actual vehicle speed. The signal processor determines the final vehicle speed on the basis of the obtained relationship.

Abstract: A vehicle ground-speed detecting apparatus, including a vehicle ground-speed sensor for detecting a ground-speed of a vehicle that is a speed of the vehicle relative to a road surface on which the vehicle is running, and generating an output signal representative of the detected vehicle ground-speed, and a proper vehicle ground-speed determining device for obtaining as sampling vehicle ground-speeds successive values of the vehicle ground-speed represented by the output signal from the vehicle ground-speed sensor, and determining a current one of the sampling vehicle ground-speeds as a current proper vehicle ground-speed when the current sampling vehicle ground-speed falls within a current permission range based on a current estimated vehicle ground-speed, the proper vehicle ground-speed determining device determining the current proper vehicle ground-speed by correcting the current sampling vehicle ground-speed when the current sampling vehicle ground-speed does not fall within the current permission range.

Abstract: Vehicle anti-lock brake control apparatus having wheel speed sensor for detecting actual speed of a vehicle wheel, solenoid-operated valve for regulating the wheel braking pressure, and controller for controlling the valve, on the basis of the detected actual speed, and vehicle ground-speed detected by ground-speed sensor. The controller controls the valve at a controlled duty cycle, which is determined on the basis of at least a wheel speed error and a time derivative of this error. The error is obtained as a deviation of the detected actual wheel speed from a target wheel speed obtained on the basis of the detected vehicle ground-speed.

Abstract: Vehicle anti-lock brake control apparatus having wheel speed sensor for detecting actual speed of a vehicle wheel, solenoid-operated valve for regulating the wheel braking pressure, and controller for controlling the valve, on the basis of the detected actual speed, and vehicle ground-speed detected by ground-speed sensor. The controller controls the valve at a controlled duty cycle, which is determined on the basis of at least a wheel speed error and a time derivative of this error. The error is obtained as a deviation of the detected actual wheel speed from a target wheel speed obtained on the basis of the detected vehicle ground-speed.

Abstract: A Doppler-effect vehicle ground-speed detecting apparatus having a transmitter fixed to a vehicle body and transmitting a wave toward a road surface on which the vehicle is running, a receiver fixed to the body and receiving a portion of the wave reflected by the road surface, and a ground-speed determining device for determining a ground-speed of the vehicle relative to the road surface, on the basis of a transmitting frequency of the wave as transmitted by the transmitter and a receiving frequency of the wave as received by the receiver. The ground-speed determining device determines the ground-speed of the vehicle, on the basis of a parameter which changes with an angle of the vehicle body relative to the road surface in a plane parallel to a running direction of the vehicle and perpendicular to the road surface, as well as on the basis of a difference between the transmitting and receiving frequencies.

Abstract: A fuel injection control apparatus which controls the regular fuel injection amount based on a control law determined in accordance with a fuel dynamic model showing the dynamics of fuel flowing into an engine cylinder using as state variables the amount of fuel sticking to the walls of the intake passage and the amount of fuel evaporating in the intake passage.During deceleration operation, the regular fuel injection is stopped, the control law correction fuel injection amount is determined from the parameter values of the fuel dynamic model, the true values of the rate of fuel sticking to the walls of the intake passage and the rate of remainder of sticking fuel, which are parameters of the fuel dynamic model, are identified based on the amount of fuel injection, the amount of air flowing into the cylinder, and the air-fuel ratio, and the control law is corrected based on the results of the identification.