AUTOMATIC BRAKE DEVICE FOR VEHICLE

摘要

PURPOSE:To perform proper brake according to a friction factor by providing an estimating means to estimate a road friction factor from the control state during operation of a control means and a setting means to set a target speed from the estimated road friction factor. CONSTITUTION:A computing unit 32 to receive a signal from a radar unit 31 computes a distance to a front obstacle and a relative speed by means of a delay time (a Doppler shift) from a point of a time when a wave received by a radar is transmitted. An alarm display unit 46 is provided with an alarm buzzer and distance display part 48 which receives signals from a control unit 45. A road friction factor mulambda is a function of an acceleration deceleration speed dVw/dt of a wheel rotation speed and a brake pressure PB. The acceleration deceleration speed dVw/dt is obtained by differentiating a signal Vw from a number of revolutions of wheel sensor 51.