In the realm of high-performance manufacturing, particularly in aerospace and related industries, drill bits with intricate geometries play a pivotal role. However, the precise measurement of these cutting tools has long been a challenging task due to their complex reflective properties, surface morphology, and the numerous parameters within small dimensions. A recent study published in Engineering presents a novel solution to this problem through the development of a correlated fusion vision dual-platform that combines 2D and 3D measurement techniques with high accuracy and efficiency.

The research, led by Wenqi Wang, Wei Liu, and Zhenyuan Jia from Dalian University of Technology, introduces an innovative hybrid measurement system designed specifically for drill bits with complex geometries, such as those featuring sawtooth characteristics. The system integrates a bi-telecentric lens for 2D imaging and a shape-from-focus method for 3D topography reconstruction. This dual-platform approach allows for the comprehensive measurement of both 2D parameters, like length and angle, and 3D parameters, such as spatial angles and surface topography.

One of the key innovations of this study is the development of an adaptive illumination method for 2D imaging. Traditional lighting sources often fail to provide the necessary contrast for accurate feature extraction due to the complex surface morphology of drill bits. To address this, the researchers designed a dome-shaped LED array that can dynamically adjust illumination patterns to enhance image quality. This adaptive lighting system ensures high-contrast imaging, which is crucial for precise feature extraction and measurement.

In addition to the adaptive lighting, the study proposes an improved focus measure for 3D reconstruction, termed ITene-Gabor. This method combines grayscale gradient and frequency information to enhance the accuracy and robustness of the focus evaluation process. The ITene-Gabor measure outperforms conventional focus measures in terms of sensitivity, noise resistance, and unimodality, leading to higher quality 3D point cloud reconstructions.

The researchers conducted extensive experiments to validate the effectiveness of their proposed system and methods. The results demonstrated that the developed equipment achieved measurement deviations of less than 3 μm for length and 0.5° for angle compared to a commercial microscope. The measurement efficiency was also impressive, averaging 30 s per parameter. These findings confirm the high accuracy, effectiveness, and reliability of the proposed method and system for measuring all drill bit parameters.

The study’s conclusions highlight the potential for the correlated fusion vision dual-platform to be extended to other complex industrial products. This system could serve as a basis for developing universal measurement equipment, offering valuable references for the advancement of precision measurement technologies in various manufacturing sectors.

The paper “Precise 2D and 3D Hybrid Measurement of Drill Bits with Complex Geometries,” is authored by Wenqi Wang, Wei Liu, Yang Liu, Yang Zhang, Zhenyuan Jia. Full text of the open access paper: https://doi.org/10.1016/j.eng.2025.03.035. For more information about Engineering, visit the website at https://www.sciencedirect.com/journal/engineering.