Inventors:
Joan Arwine - Springboro OH, US
Jon Zumberge - Dayton OH, US
Assignee:
DELPHI AUTOMOTIVE SYSTEMS
International Classification:
B60T008/34
B60T013/70
US Classification:
303/113100, 303/015000, 303/166000
Abstract:
Systems and methods are disclosed to control a braking system. One method provides a command signal to a valve to control fluid pressure to a wheel brake in a braking system includes the steps of determining a pressure signal using a first control technique based on a first set for control gains and a pressure command signal, determining a first current signal based upon the pressure command signal, subtracting an actual pressure signal from the pressure command signal to produce an error signal, and determining a second current signal using a second control technique based on the second set of control gains and the error signal. The method further includes subtracting a supply pressure actual signal from a supply pressure nominal signal to produce a pressure differential signal, multiplying the pressure differential signal by a selected gain to produce a third current signal, and summing the first current signal, the second current signal and the third current signal to produce an output signal. One braking system includes a master cylinder for delivering pressurized fluid in response to a mechanical input. A first sensor provides a supply pressure signal in response to fluid pressure delivered by an accumulator. A second sensor provides a wheel pressure signal in response to fluid pressure applied to at least one wheel brake. A controller is responsive to the wheel pressure signal and supply pressure signal to produce a pressure command signal. The controller implements the steps of determining a first current signal using a first control technique based on a first set for control gains and the pressure command signal, determining an actual pressure signal based upon the wheel pressure signal. subtracting an actual pressure signal from the pressure command signal to produce an error signal, and determining a second current signal using a second control technique based on a second set of control gains and the error signal. The controller also implements the steps of subtracting the supply pressure signal from a supply pressure nominal signal to produce a pressure differential signal, multiplying the pressure differential signal by a selected gain to produce a third current signal, and summing the first current signal, the second current signal and the third current signal to produce an output signal.