New real-time non-contact probe using Gaussian convolution smooth technique for in-process inspection

A new in-process, non-contact laser probe is presented to measure diameter of turned workpieces on lathe CNC machine in in-process. The principle technique of the probe is based on the differential laser Doppler technique. New Doppler analysis techniques are developed based on the circumstance of scattered lights from the solid surface and noises. The processing techniques use Gaussian distribution approaches in order to extract the Doppler frequency and calculate the diameter of the workpiece. The performance of the probe is evaluated by comparing of the calculating diameters with the reference values given by a precision CMM. The probe delivers an uncertainty of a few micrometers over a range of 100 mm.