Monitoring Rotating Tools Using Laser Diffraction

Abstract

This paper introduces a new technique for monitoring multiple tooth rotating tools. The technique is based on laser diffraction. A narrow slit is constructed between the cutting edge of a cutter and a sharp straight blade placed parallel to the cutting edge as a reference. A laser beam is projected onto the slit and consequently a diffraction pattern consisting of a number of fringes is created behind the slit. By comparing the fringe spacing variation, cutting edge wear can be obtained. This technique has high resolution and a wide range of measurement. In addition, the measurement can be correlated to the commonly used flank wear measure (VB). The technique can be used for rotating tools such as milling and drilling. Experimental results in end-milling processes show that the technique is repeatable and accurate. With its fast speed, high resolution and reliability, it is expected that the technique has great potential for industrial applications.