Patent ID: 8244494
Filing Date: 2012-08-14
Classification: G01B

Abstract:
1. A method for determining a distance between pieces of a thermal processing system using a processor or an electronic circuit, the method comprising: directing a laser beam or a plasma arc on to a first or a second piece; applying, using the processor or electronic circuit, at the first or second piece, a source AC signal different from a source signal of the laser beam or the plasma arc, the source AC signal including a source DC offset; measuring, using the processor or electronic circuit, at the first or second piece, an AC signal generated by the source AC signal that is different from the source signal of the laser beam or the plasma arc, the AC signal including a DC offset; and determining, using the processor or electronic circuit, the distance using a calibration data set that includes data values associated with the measured AC signal and the source AC signal that is different from the source signal of the laser beam or the plasma arc, deriving the distance by calculating a gap capacitance between the first piece and the second piece, the derived gap capacitance is a function of at least the measured AC signal and the source AC signal, wherein the calibration data set further includes the gap capacitance.