Patent ID: 7475760

Claim:
An electric brake system comprising: an electric motor having a portion moveable along a path between a plurality of positions for moving a brake pad and applying a selectable amount of braking force on a brake rotor, wherein one of said plurality of positions being a minimal contact position associated with minimal friction between the brake pad and the brake rotor, said minimal contact position operable to change among said plurality of positions over time; an electric controller for controlling said electric motor to move said portion along said path between said minimal contact position and at least one other of said plurality of positions for selecting the amount of braking force; and at least one sensor for sensing at least two of motor current, motor acceleration, controller voltage, motor speed, motor voltage, and motor temperature of said electric motor, and communicating the sensed conditions to said controller, wherein said controller being operable to change said minimal contact position along said path in response to the sensed conditions communicated by said at least one sensor, wherein said electric controller is also defined as being programmed with an inverse matrix derived from raw data associated with at least two of motor current, motor acceleration, controller voltage, motor speed, motor voltage, and motor temperature correlated with respect to a secondary position adjacent said minimal contact position and wherein said electric controller is further defined as being programmed to calculate a Mahalanobis Distance to evaluate whether the portion is at the minimal contact position along the path based in part on the inverse matrix derived from the raw data and in part from the sensed conditions communicated by said at least one sensor.