Patent ID: 7278694

Claim:
An anti-lock brake system for a vehicle comprising: a plurality of apply valves, each of said apply valves adapted to be connected to a wheel brake cylinder associated with a vehicle wheel, each of said apply valves operable to increase the hydraulic brake pressure applied to said associated wheel brake cylinder; a plurality of dump valves, each of said dump valves adapted to be connected to a wheel brake cylinder associated with a vehicle wheel, each of said dump valves operable to decrease the hydraulic brake pressure applied to said associated wheel brake cylinder; a plurality of wheel speed sensors, each of said wheel speed sensors associated with each vehicle wheel; and a brake system controller electrically connected to said wheel speed sensors and a solenoid coil associated with each of said apply and dump valves, said controller including an algorithm and operable to monitor said wheel speed sensors and, upon determining a potential wheel lock-up situation during a vehicle braking cycle, said controller being further operable to cycle the apply and dump valves associated with the vehicle rear wheels continuously between apply and dump modes to determine an estimated maximum friction wheel slip and then to utilize said estimated maximum friction wheel slip to determine reference velocities that are used to continuously control the apply and dump valves associated with the vehicle front wheels to optimize vehicle braking.