Abstract: A memory circuit increments when sensor fallout or short solenoid energization is detected in a wheel slip control system. A disable or alarm signal is generated when the memory contents reach a predetermined threshold.

Abstract: A control system for adjusting the pressure applied to fluid-controlled brake actuating mechanisms in response to an incremental decrease in wheel velocity from the time a deceleration threshold is reached, at which time a gradual adjustment of brake line fluid pressure is effected, and monitored to determine when a continuously-variable reference increment of wheel speed .DELTA.v has been exceeded, at which time a sharp reduction in brake line fluid pressure is effected. This continuously-variable reference increment .DELTA.v is defined in each cycle by (1) the value of wheel velocity at the time said deceleration threshold is reached and (2) a variable reference signal which is related to both wheel speed and deceleration during periods of deceleration of the monitored wheel, and is related only to acceleration during periods of acceleration of the monitored wheel. A velocity predictor circuit sets a minimum velocity decrease threshold on the reapplication of brakes.

Abstract: A delay circuit in a wheel-slip control system prevents spurious triggering of the wheel slip control system due to false signals originating in misalignment, dirt or damage in wheel speed sensors. A time-delay circuit requires completion of a first cycle of wheel slip control system actuation, wherein both deceleration and velocity criteria must both be met, before deceleration signals alone are allowed to actuate the wheel slip control circuits. A timer enables subsequent cycles of actuation of the wheel slip control system by acceleration alone during a normal sequence of actuations within one brake application.

Abstract: A signal processing circuit provides control signals suitable for controlling the application of braking pressure in a fluid-control brake actuating mechanism. An input signal whose amplitude is proportional to wheel speed is differentiated to yield a signal proportional to acceleration and deceleration. A first output signal is generated when a predetermined deceleration threshold is exceeded. A second output signal is generated when both a deceleration and a velocity threshold are simultaneously exceeded. The second output signal is maintained until the velocity signal exceeds a variable reference threshold which varies with acceleration alone during acceleration.

Abstract: A control system for adjusting the pressure applied to fluid-controlled brake actuating mechanisms in response to predetermined variations in wheel speed and rate of change of wheel speed brought about by the application of fluid pressure to the wheel brake actuating mechanisms. Signals proportional to the angular velocity and rate of change of angular velocity of a selected wheel are employed to control the sequence and duration of the energization and de-energization of the solenoid valves in a modulator valve assembly. The incremental decrease in wheel velocity from the time said deceleration threshold is reached, at which time a gradual adjustment of brake line fluid pressure is effected, is monitored to determine when a continuously-variable reference increment of wheel speed .DELTA. v has been exceeded, at which time a sharp reduction in brake line fluid pressure is effected. This continuously-variable reference increment .DELTA.