Patent ID: 7669344

Claim:
A coordinate measuring machine comprising: a table; a bridge movable along an axis with respect to the table; a drive element for driving the bridge; a carriage movable on the bridge; a probe mounted to the carriage; a scale operative to permit scale readings indicating a position of a portion of the bridge along the axis; and a computer including a memory storing calibration data, wherein: the calibration data includes hysteresis error data; the hysteresis error data includes a hysteresis function that calculates an error value as a function of a distance of the carriage from a reference position, the reference position being a position of the scale; the computer stores the reference position, from which the distance of the carriage is measured, and the hysteresis function includes a ratio of: (a) the distance of the carriage to the reference position to (b) a predetermined distance; and the predetermined distance is a distance between the position of a calibration block and the reference position.