scholarly journals Automated evaluation of the surface point quality in dimensional X-ray computed tomography

2020 ◽  
Vol 87 (2) ◽  
pp. 111-121 ◽  
Author(s):  
Andreas Michael Müller ◽  
Lorenz Butzhammer ◽  
Florian Wohlgemuth ◽  
Tino Hausotte
Keyword(s):  
Computed Tomography ◽  
Surface Point ◽  
Random Measurement Error ◽  
X Ray ◽  
Random Measurement ◽  
Automated Evaluation ◽  
Dimensional Measurements ◽  
X Ray Computed ◽  
Model Measurement

AbstractX-ray computed tomography (CT) enables dimensional measurements of numerous measurands with a single scan, including the measurement of inner structures. However, measurement artefacts complicate the applicability of the technology in some cases. This paper presents a methodology to assess the surface point quality of computed tomography measurements without the requirement of a CAD model. Measurement artefacts lowering the surface point quality can therefore automatically be detected. The correlation of quality values with the random measurement error is demonstrated. The presented method can in principle be used to weight single fit points to reduce the measurement uncertainty of CT measurements.

scholarly journals Effects of off-focal radiation on dimensional measurements in industrial cone-beam micro-focus X-ray computed tomography systems

2020 ◽  
Vol 66 ◽  
pp. 472-481
Author(s):  
Nadia Flay ◽  
Stephen Brown ◽  
Wenjuan Sun ◽  
Thomas Blumensath ◽  
Rong Su
Keyword(s):  
Computed Tomography ◽  
Cone Beam ◽  
X Ray ◽  
Dimensional Measurements ◽  
X Ray Computed

scholarly journals OBSERVATIONS ON THE PERFORMANCE OF X-RAY COMPUTED TOMOGRAPHY FOR DIMENSIONAL METROLOGY

2016 ◽  
Vol XLI-B5 ◽  
pp. 25-31
Author(s):  
H. C. Corcoran ◽  
S. B. Brown ◽  
S. Robson ◽  
R. D. Speller ◽  
M. B. McCarthy
Keyword(s):  
Computed Tomography ◽  
Reverse Engineering ◽  
X Rays ◽  
Dimensional Metrology ◽  
Beam Hardening ◽  
X Ray ◽  
Accuracy And Precision ◽  
Dimensional Measurements ◽  
X Ray Computed

X-ray computed tomography (XCT) is a rising technology within many industries and sectors with a demand for dimensional metrology, defect, void analysis and reverse engineering. There are many variables that can affect the dimensional metrology of objects imaged using XCT, this paper focusses on the effects of beam hardening due to the orientation of the workpiece, in this case a holeplate, and the volume of material the X-rays travel through. Measurements discussed include unidirectional and bidirectional dimensions, radii of cylinders, fit point deviations of the fitted shapes and cylindricity. Results indicate that accuracy and precision of these dimensional measurements are affected in varying amounts, both by the amount of material the X-rays have travelled through and the orientation of the object.

INVESTIGATION OF POLYMER COMPOSITE MATERIAL SAMPLES BY X-RAY COMPUTED TOMOGRAPHY AND PROCESSING OF TOMOGRAMS WITH THE IMAGE OF THE VOLUME FRACTION OF POROSITY

2021 ◽  
pp. 105-113
Author(s):  
A.A. Demidov ◽  
◽  
O.A. Krupnina ◽  
N.A. Mikhaylova ◽  
E.I. Kosarina ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Polymer Composite ◽  
Volume Fraction ◽  
Filter Material ◽  
Polymer Composite Material ◽  
Tomographic Images ◽  
X Ray ◽  
X Ray Computed ◽  
Porosity Volume Fraction

The question of the quality of samples made of polymer composite materials and its verification by x-ray computed tomography is considered. The capabilities of North Star Imaging X5000 tomograph were studied and the samples from PCM were examined for detection and evaluation of the porosity volume fraction. The factors influencing the accuracy of the estimation of the porosity volume fraction are investigated. Namely the size voxel, a filter material, quantity of projections. On the other hand, the size вокселя defines resolution of the digital image, the relation depends on a material of the applied filter a signal/noise, productivity of control worsens with growth of quantity of projections. The choice of optimum values of the listed parametres is necessary for satisfactory quality received tomographic images.

scholarly journals OVERVIEW OF THE USE OF X-RAY EQUIPMENT IN ELECTRONICS QUALITY TESTS

2021 ◽  
Vol 11 (2) ◽  
pp. 26-29
Author(s):  
Magdalena Michalska
Keyword(s):  
Computed Tomography ◽  
Image Formation ◽  
Electronics Industry ◽  
Circuit Board ◽  
Surface Mount Technology ◽  
X Ray ◽  
Surface Mount ◽  
X Ray Computed

Surface-mount technology is now widely used in the production of many components. The development of the miniaturised electronics industry forces the development of increasingly accurate inspection methods. X-ray and computed tomography are methods to accurately assess the quality of a circuit board. The article discusses the basics of image formation of the tested electronics, the development of the design of the devices used and examples of x-ray, computed tomography applications.

Development of Dimensional X-Ray Computed Tomography

2015 ◽  
Vol 9 (5) ◽  
pp. 567-571 ◽  
Author(s):  
Hiroyuki Fujimoto ◽  
◽  
Makoto Abe ◽  
Sonko Osawa ◽  
Osamu Sato ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Coordinate Measuring Machine ◽  
National Metrology Institute ◽  
Maximum Deviation ◽  
Dimensional Metrology ◽  
X Ray ◽  
Tomography System ◽  
Dimensional Measurements ◽  
X Ray Computed ◽  
Measuring Machine

Recently, a strong need has arisen for a dimensional X-ray computed tomography system that is capable of dimensional measurements. This is because the speedy realization of dimensional measurements for outward forms and inward forms on dense spatial points remarkably simplifies and accelerates production loop. However, although the image obtained via XCT describes the structure clearly and in great detail, dimensional metrology by means of XCT is not simple. The National Metrology Institute of Japan has been carrying out performance tests using gauges that include the gauges proposed in ISO10360. In this work, the magnification variation correction is carefully presented, and a maximum deviation of less than 5 μm is shown to be possible by means of the measurement of the forest phantom of 27 ruby spheres, the locations of which are calibrated by the coordinate measuring machine.

Clear wood content in standing trees predicted from branch scar measurements with terrestrial LiDAR and verified with X-ray computed tomography

2014 ◽  
Vol 44 (2) ◽  
pp. 145-153 ◽  
Author(s):  
Stefan M. Stängle ◽  
Franka Brüchert ◽  
Ursula Kretschmer ◽  
Heinrich Spiecker ◽  
Udo H. Sauter
Keyword(s):  
Computed Tomography ◽  
Wood Quality ◽  
European Beech ◽  
Internal Quality ◽  
Clear Wood ◽  
Terrestrial Lidar ◽  
X Ray ◽  
Standing Trees ◽  
X Ray Computed

Knowledge about the wood quality of standing trees is crucial in that it serves as an excellent means for nearly all stages of the wood-supply chain. Better information about internal wood characteristics can be derived from the outside appearance by establishing a correlation between the bark characteristics of a stem and its internal quality. This paper presents an approach where the quality determination of standing trees using a terrestrial light detection and ranging (LiDAR) system is combined with the information about internal quality of logs using X-ray computed tomography (CT). Results show a high accuracy for branch scar measurements with terrestrial LiDAR and knot measurement with CT. A strong correlation between scar seal quotient and the amount of clear wood could be confirmed using European beech (Fagus sylvatica L.) as an example. Quality grading of virtually segmented logs using terrestrial LiDAR and CT showed moderate correlation; 62.5% of the segments were allocated to the same grade by both approaches. In conclusion, terrestrial LiDAR in forest inventory could be used as an instrument to predict inner wood quality in greater detail by gathering data on the outer appearance and branch scars of standing trees. This additional knowledge has the potential to improve forest planning, bucking instructions, and a roundwood allocation that meets industry demand.

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