研究目的
To develop and validate a fully automated multi-step scaling system for photogrammetric micro-measurements to eliminate operator dependency and improve accuracy compared to manual methods.
研究成果
The automated HDFF method effectively reduces operator dependency and improves measurement accuracy in photogrammetric micro-measurements, with errors below 10 μm. It shows better performance than the manual method in most cases, offering higher repeatability and efficiency, making it suitable for industrial applications in micro-feature inspection.
研究不足
The method may have limited performance on bright objects due to light reflections, and computational time is significant (average 30.75 s per image). Some positions could not be processed due to unfavorable light conditions, indicating sensitivity to environmental factors.
1：Experimental Design and Method Selection:
The study uses a hybrid depth from focus (HDFF) method combined with machine vision algorithms (LBP and Otsu segmentation) for automated scaling. It involves capturing images with high and low diaphragm apertures, segmenting focus areas, detecting centroids, and computing scale factors.
2：Sample Selection and Data Sources:
Millimeter-sized certified workpieces (ball-bar and coaxial cylinders) are used, with dimensions certified by SITEC (uncertainty 3 μm). Images are captured using a Canon EOS 400D camera with specific settings.
3：List of Experimental Equipment and Materials:
Canon EOS 400D SLR Camera, Canon EF-S 60 mm f/
4：8 macro lens, 36-mm extension tube, tripod stand, rotating table, Notebook Lenovo with Intel Core i7 and 8 GB RAM, software:
MATLAB, Agisoft PhotoScan Pro, Geomagic Control.
5：Experimental Procedures and Operational Workflow:
Capture images with f2.8 and f20 apertures; process images in MATLAB for segmentation and centroid detection; use Agisoft for 3D point cloud generation; perform post-processing in Geomagic Control; compare results with manual method and certified dimensions.
6：8 and f20 apertures; process images in MATLAB for segmentation and centroid detection; use Agisoft for 3D point cloud generation; perform post-processing in Geomagic Control; compare results with manual method and certified dimensions. Data Analysis Methods:
5. Data Analysis Methods: Statistical analysis of measurement errors (e.g., sphere spacing error, probing error) based on VDI/VDE 2634 guideline, computation of type A uncertainties, and comparison of automated vs. manual methods.
独家科研数据包，助您复现前沿成果，加速创新突破
获取完整内容-
Canon EOS 400D SLR Camera
EOS 400D
Canon
Used for capturing high and low diaphragm aperture images in photogrammetric measurements.
-
Canon EF-S 60 mm f/2.8 macro lens
EF-S 60 mm f/2.8
Canon
Macro lens used for close-range imaging with high magnification.
-
Extension tube
36-mm extension tube
Increases the magnification ratio of the camera lens for micro-feature imaging.
-
Notebook Lenovo
Lenovo
Used for running MATLAB software and processing images.
-
Agisoft PhotoScan Pro
Version 1.2.3
Agisoft
Software for aligning images and generating 3D point clouds.
-
Geomagic Control
Geomagic
Software for post-processing and analyzing 3D point clouds.
-
MATLAB
MathWorks
Used for implementing image processing algorithms and GUI.
-
登录查看剩余5件设备及参数对照表
查看全部
