Study on the Double Pulse Laser Dynamic Electronic Speckle Measurement Based on FPGA

Abstract

Speckle pattern interferometry can be used to measure he displacement, strain and vibration, surface deformation and surface roughness. And dynamic laser speckle measurement with high accuracy has been widely used in measurement of surface deformation. Tool breakage is the main bottleneck of high-speed intermittent cutting development, therefore, obtaining stress distribution of milling tools is a base of improving the tool design and tool life. Using a speckle measurement method of double pulsed digital based on FPGA, which involves the laser cutter, tools and CCD, transforms the high-speed dynamic measurement to quasi-static measurement. As a result, we can get two speckle images of front and back milling cutter surface and calculate the deformation ,strain and stress distribution of the tool surface with analysis.