The impact of H.264/AVC on compression and non-destructive evaluation of piston data in industrial Computed Tomography

2013 ◽  
Author(s):  
Alexander Ditter ◽  
Dietmar Fey ◽  
Tobias Schon ◽  
Maik Luxa ◽  
Roland Gruber
Keyword(s):  
Computed Tomography ◽  
Non Destructive Evaluation ◽  
Industrial Computed Tomography ◽  
The Impact ◽  
Non Destructive

Determination of GD&T Features Varying the Setting Parameters of X-Ray Computed Tomography by Response Surface Method

2020 ◽  
Vol 994 ◽  
pp. 280-287
Author(s):  
Anh Dao ◽  
Ágota Drégelyi-Kiss
Keyword(s):  
Computed Tomography ◽  
Response Surface ◽  
Response Surface Method ◽  
Measurement Errors ◽  
Surface Method ◽  
Industrial Computed Tomography ◽  
Dimensional Parameters ◽  
X Ray Computed ◽  
Set Up ◽  
Non Destructive

Measuring dimensional parameters (such as diameter, distance) by industrial computed tomography (CT) becomes more and more popular because of its advantages such as non-destructive method and short measurement time. However, the goodness of the measured values needs to be evaluated as a requirement of quality control. An aluminium test piece are designed and manufactured for mapping the measurement errors and uncertainties in case of dimensional CT measurements. In this article, the measurement errors are investigated based on the results of an experimental design, response surface method (RSM). Three main factors are varied systematically: the magnification of the CT, the numbers of views (NoV), and the set-up of the scanning mode. In the course of measurement evaluation several GD&T parameters are determined such as diameter of holes, distances between the holes, flatness and perpendicularity. The purpose of this research is to calculate the measurement errors and to determine the factors which have an effect on the dimensional CT measurement process.

scholarly journals Non-Destructive Evaluation Techniques and What They Tell Us about Wood Property Variation

Forests ◽  
2019 ◽  
Vol 10 (9) ◽  
pp. 728 ◽  
Author(s):  
Laurence Schimleck ◽  
Joseph Dahlen ◽  
Luis A. Apiolaza ◽  
Geoff Downes ◽  
Grant Emms ◽  
...  
Keyword(s):  
Multiple Scales ◽  
Wood Property ◽  
Wood Properties ◽  
Product Performance ◽  
Detailed Knowledge ◽  
Field Equipment ◽  
Property Variation ◽  
Non Destructive Evaluation ◽  
The Impact ◽  
Non Destructive

To maximize utilization of our forest resources, detailed knowledge of wood property variation and the impacts this has on end-product performance is required at multiple scales (within and among trees, regionally). As many wood properties are difficult and time-consuming to measure our knowledge regarding their variation is often inadequate as is our understanding of their responses to genetic and silvicultural manipulation. The emergence of many non-destructive evaluation (NDE) methodologies offers the potential to greatly enhance our understanding of the forest resource; however, it is critical to recognize that any technique has its limitations and it is important to select the appropriate technique for a given application. In this review, we will discuss the following technologies for assessing wood properties both in the field: acoustics, Pilodyn, Resistograph and Rigidimeter and the lab: computer tomography (CT) scanning, DiscBot, near infrared (NIR) spectroscopy, radial sample acoustics and SilviScan. We will discuss these techniques, explore their utilization, and list applications that best suit each methodology. As an end goal, NDE technologies will help researchers worldwide characterize wood properties, develop accurate models for prediction, and utilize field equipment that can validate the predictions. The continued advancement of NDE technologies will also allow researchers to better understand the impact on wood properties on product performance.

scholarly journals Selection and evaluation of spherical acquisition trajectories for industrial computed tomography

2021 ◽  
Vol 477 (2250) ◽  
pp. 20210192
Author(s):  
Fabian Bauer ◽  
Matthias Goldammer ◽  
Christian U. Grosse
Keyword(s):  
Computed Tomography ◽  
Image Quality ◽  
Optimization Method ◽  
Three Dimensions ◽  
Trajectory Design ◽  
Destructive Testing ◽  
Monte Carlo Algorithms ◽  
Quantitative Metrics ◽  
Industrial Computed Tomography ◽  
Non Destructive

In conventional industrial computed tomography, the source–detector system rotates in equiangular steps in-plane relative to the part of investigation. While being by far the most frequently used acquisition trajectory today, this method has several drawbacks like the formation of cone beam artefacts or limited usability in case of geometrical restrictions. In such cases, the usage of alternative spherical trajectories can be beneficial to improve image quality and defect visibility. While investigations have been performed to relate the influence of the trajectory choice in the typical metrological case of a high number of available projections, so far barely any work has been done for the case of few source–detector poses, which is more relevant in the field of non-destructive testing. In this work, we provide an overview of quantitative metrics that can be used to assess the image quality of reconstructed computed tomography volumes, discuss their advantages and drawbacks and propose a framework to investigate the performance of several non-standard trajectories with respect to previously defined regions of interest. Inspired by pseudorandom sampling methods for Monte–Carlo-algorithms, we also suggest an entirely new trajectory design, the low-discrepancy spherical trajectory, which extends the concept of equiangular planar trajectories into three dimensions and can be used for benchmarking and comparison with other spherical trajectories. Last, we use an optimization method to calculate task-specific acquisition trajectories and relate their performance to other spherical designs.

X-Ray Computed Tomography: A Potentially Destructive “Non-Destructive Evaluation” Technique

2019 ◽  
Author(s):  
Ryan Ross ◽  
Gil Garteiz ◽  
Stephanie Zajac
Keyword(s):  
Computed Tomography ◽  
Evaluation Technique ◽  
Total Ionizing Dose ◽  
X Ray ◽  
Non Destructive Evaluation ◽  
X Ray Computed ◽  
Flight Hardware ◽  
Non Destructive

Abstract Characterization of Computed Tomography X-Ray ionizing dose will be presented along with a methodology to protect space bound flight hardware from exceeding total ionizing dose (TID) budget prior to mission completion.

Impedance-based non-destructive evaluation of additively manufactured parts

2017 ◽  
Vol 23 (3) ◽  
pp. 589-601 ◽  
Author(s):  
Mohammad I. Albakri ◽  
Logan D. Sturm ◽  
Christopher B. Williams ◽  
Pablo A. Tarazaga
Keyword(s):  
Complex Geometry ◽  
Cost Effective ◽  
Learning Context ◽  
Content Type ◽  
Electromechanical Impedance ◽  
Internal Porosity ◽  
Non Destructive Evaluation ◽  
The Impact ◽  
Non Destructive ◽  
Am Processes

Purpose This work proposes the utilization of electromechanical impedance measurements as a means of non-destructive evaluation (NDE) for additive manufacturing (AM). The effectiveness and sensitivity of the technique for a variety of defect types commonly encountered in AM are investigated. Design/methodology/approach To evaluate the feasibility of impedance-based NDE for AM, the authors first designed and fabricated a suite of test specimens with build errors typical of AM processes, including dimensional inaccuracies, positional inaccuracies and internal porosity. Two polymer AM processes were investigated in this work: material jetting and extrusion. An impedance-based analysis was then conducted on all parts and utilized, in a supervised learning context, for identifying defective parts. Findings The newly proposed impedance-based NDE technique has been proven to be an effective solution for detecting several types of print defects. Specifically, it was shown that the technique is capable of detecting print defects resulting in mass change (as small as 1 per cent) and in feature displacement (as small as 1 mm) in both extruded nylon parts and jetted VeroWhitePlus parts. Internal porosity defects were also found to be detectable; however, the impact of this defect type on the measured impedance was not as profound as that of dimensional and positional inaccuracies. Originality/value Compared to currently available NDE techniques, the newly proposed impedance-based NDE is a functional-based technique with the advantages of being cost-effective, sensitive and suitable for inspecting AM parts of complex geometry and deeply embedded flaws. This technique has the potential to bridge the existing gaps in current NDE practices, hence paving the road for a wider adoption of AM to produce mission-critical parts.

Non-Destructive Analysis of Ancient Chinese Bronzes Utilizing Industrial Computed Tomography

1990 ◽  
Vol 185 ◽  
Author(s):  
Ellen B. Avril ◽  
Stephen D. Bonadies
Keyword(s):  
Computed Tomography ◽  
Three Dimensional ◽  
Conventional Radiography ◽  
Art Museum ◽  
Digital Radiograph ◽  
Industrial Computed Tomography ◽  
Different Types ◽  
Dimensional Reconstruction ◽  
Industrial Ct ◽  
Non Destructive

AbstractIndustrial computed tomography was used to study eight Chinese bronzes from the collection of the Cincinnati Art Museum. With industrial CT two different types of images can be formed, the digital radiograph (DR) which produces a twodimensional image of the object and computed tomography (CT) which takes a crosssectional slice. A further advancement discussed is the use of General Electric's Digital Replica™ method to create a three-dimensional reconstruction of the object which enables one to view interior surfaces and to dissect joins. The paper discusses the numerous advantages of the industrial CT over conventional radiography.

Influences of Surface Determination for Measurements Obtained by Industrial Computed Tomography

2014 ◽  
Vol 683 ◽  
pp. 142-146 ◽  
Author(s):  
Teodor Tóth ◽  
Alexander Végh ◽  
Miroslav Dovica ◽  
Jozef Živčák
Keyword(s):  
Computed Tomography ◽  
Conveyor Belt ◽  
Digital Data ◽  
Output Control ◽  
Measuring Devices ◽  
Industrial Computed Tomography ◽  
Conveyor Belts ◽  
Porosity Analysis ◽  
Visual Shape ◽  
The Impact

At present emphasis is placed on input or output control of products in the manufacturing process. One of the criteria is the dimensional analysis or porosity analysis of products. In the case that products are of complicated shapes, or measurements are to be taken in places which are not accessible to standard measuring devices (manual measurements, coordinate measuring machines) the use of computed tomography is one of the possibilities for obtaining the desired dimensions. These technologies work with digital data and therefore the surfaces which are to be assessed must be created on the basis of determined criteria. Surface determination is one of the most important settings during the evaluation of the visual shape (state) of a surface and assessing dimensions. During such evaluation this is the main parameter which globally influences the precision of the obtained data. In the case of an unsuitably determined surface the obtained results can vary from reality even by several tenths of a millimeter depending on the scanned object and the scanning conditions. The conveyor belts are composed of two or more materials with different densities, such as rubber and textile fibers. In cooperation with Faculty of Mining, Ecology, Process Control and Geotechnology is tested and evaluated the effect of the impactor with various energy into conveyor belt. The correct surface determination for selected material is necessary to evaluate the dimensions, the damage and pores. The article deals with the impact of surface determination on the result of a measurement.

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