Movement control by a metrological instrument

摘要

A measurement probe is carried by a carriage movable in a first direction to cause the measurement probe to traverse a measurement path across a surface of an object received by a support surface to provide measurement data representing variations in a second direction different from the first direction of surface features along the measurement path. The support surface is movable in a third direction different from the first and second directions. Measurement of a surface area is effected by controlling the carriage to cause the measurement probe to traverse a plurality of measurement paths across an area of the surface of an object mounted on the support surface and by controlling the support surface to move in the third direction after each measurement path traverse. Measurement data thus obtained for a reference sphere of previously known radius is used to determine the relative orientation of the first and third directions. Measurement data provided by the measurement probe may then be corrected in accordance with any error in the determined relative orientations of the first and third directions.