AUTOMATED MEASUREMENT OF TOOL WEAR USING AN IMAGE-PROCESSING SYSTEM

This paper presents a method for measuring tool wear parameters based on two dimensional image information. The tool wear images were obtain ed from an ITV camera with magnifying and lighting devices, and were a nalyzed using image processing techniques such as thresholding, noise filtering and boundary tracing. Thresholding was used to transform the captured gray scale image into a binary image for rapid sequential im age processing. The threshold level was determined using a novel techn ique in which the brightness histograms of two concentric windows cont aining the tool wear image were compared. The use of noise filtering a nd boundary tracing to reduce the measuring errors was explored. Perfo rmance tests of the measurement precision and processing speed reveale d that the direct method was highly effective in intermittent tool wea r monitoring.