Anti-lock braking system and method using a polynomial processor

DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT FIG.
1 illustrates a block diagram representation of an antilock braking system in accordance with an embodiment of the present invention.
In particular, an anti-lock braking system for a vehicle is presented, the vehicle having a plurality of wheels, and a braking system that includes a brake for braking at least one of the plurality of wheels and a brake valve 22 for controlling a braking pressure in the brake in response to a brake valve signal 20.
Wheel speed sensors 10 are coupled to one or more wheels of a vehicle.
Each wheel speed sensor provides a corresponding input signal 12 that is proportional to wheel speed of the corresponding wheel of the vehicle.
Several configurations are commonly in use in the art.
In one embodiment, a four-wheeled vehicle has four wheel speed sensors, one sensors for each wheel.
In other embodiments, three wheel speed sensors are used for a four-wheeled vehicle.
In this case, the front wheels are each equipped with a wheel speed sensor and the average speed of the rear wheels is determined collectively by a single sensor that is coupled to the rear differential of the vehicle.
Other configurations are similarly possible.
In one embodiment of the present invention wheel speed sensors 10 includes a multi-toothed wheel and pick-up that generates a series of pulses whose frequency is proportional to the speed of the wheel.
The wheel speed sensors 10 further includes a frequency to voltage converter for converting the pulsed signal to a d.
c.
value in proportion to the velocity of the wheel.
Other wheel speed sensors can also be used as will be apparent to one of ordinary skill in the art.
A polynomial processor 14 is in communication with the plurality of wheel speed sensors 10 and is response to the plurality of input signals 12.
Polynomial processor 14 generates a control signal 16 based on a nonlinear polynomial function of the plurality of input signals 12.
Post-processor 18 generates the brake valve signal 20 based on the control signal so as to provide cyclic control of the braking pressure in the brake 22 in anti-lock braking conditions