Search results for "Inspec"
showing 10 items of 171 documents
HD-RTI: an adaptive multi-light imaging approach for the quality assessment of manufactured surfaces
2021
International audience; Reflectance Transformation Imaging (RTI) is a technique for estimating surface local angular reflectance from a set of stereo-photometric images captured with variable lighting directions. The digitization of this information fully fits into the industry 4.0 approach and makes it possible to characterize the visual properties of a surface. The proposed method, namely HD-RTI, is based on the coupling of RTI and HDR imaging techniques. This coupling is carried out adaptively according to the response at each angle of illumination. The proposed method is applied to five industrial samples which have high local variations of reflectivity because of their heterogeneity of…
A refined range image registration technique for multi-stripe laser scanner
2006
Nowadays, visual inspection is very important in the quality control for many industrial applications. However, the complexity of most 3D objects constrains the registration of range images; a complete surface is required to compare the acquired surface to the model. Range finders are very used to digitalize free form shape objects with large resolutions. Moreover, one single view is not enough to reconstruct the whole surface due to occlusions, shadows, etc. In these situations, the motion between reconstructed partial views are required to integrate all surfaces in a single model. However, the use of positioning systems is not always available or adequate due mainly to the size of the obj…
Systematic Error Correction of a 3D Laser Scanning Measurement Device
2011
International audience; Non-contact measurement techniques using laser scanning have the advantage of fast acquiring large numbers of points. However, compared to their contact-based counterparts, these techniques are known to be less accurate. The work presented in this paper aims at improving the accuracy of these techniques through an error correction procedure based on an experimental process that concerns mechanical parts. The influence of the three parameters defining the relative position and the orientation between the sensor and the surface is studied. The process used to build an experimental global model of error is presented and applied to a typical part composed of planes or sk…
An Automated Visual Inspection System for the Classification of the Phases of Ti-6Al-4V Titanium Alloy
2013
Metallography is the science of studying the physical properties of metal microstructures, by means of microscopes. While traditional approaches involve the direct observation of the acquired images by human experts, Com-puter Vision techniques may help experts in the analysis of the inspected mate-rials. In this paper we present an automated system to classify the phases of a Titanium alloy, Ti-6Al-4V. Our system has been tested to analyze the final products of a Friction Stir Welding process, to study the states of the micro-structures of the welded material.
Continuous monitoring of an intentionally-manufactured crack using an automated welding and in-process inspection system
2020
Abstract Automated weld deposition coupled with the real-time robotic Non-Destructive Evaluation (NDE) is used in this paper. For performance verification of the in-process inspection system, an intentionally embedded defect, a tungsten rod, is introduced into the multi-pass weld. A partially-filled groove (staircase) sample is also manufactured and ultrasonically tested to calibrate the real-time inspection implemented on all seven layers of the weld which are deposited progressively. The tungsten rod is successfully detected in the real-time NDE of the deposited position. The same robotic inspection system was then used to continuously monitor an intentionally-manufactured crack for 20 h.…
Training and Deployment as a Basis for Usability Engineering of Mobile Systems
2008
Usability engineering of mobile systems challenges existing methods and raises new concerns. Usability evaluations are frequently described as a separate discipline and in many cases usability evaluations are separate activities within the design and development of systems. This paper presents a development project where training in and the deployment of a mobile system were used to identify usability problems. The project aimed to develop a mobile system to supporting information processes for workers on building sites. An iterative usability evaluation process was conducted the process was refined and validated using two action research projects. The approach of the research was user-cent…
Usability remote evaluation: METBA system
2012
Usability as well as accessibility is a key aspect in development of human-computer interaction. This paper presents the basis of usability evaluation methodology and reviews the methodology used in empirical studies of usability evaluation for disabled people. Finally, we present a solution (METBA) as a system for managing the information related to evaluation of human behavioral observation contents that is used for the registration and management of the information derived from remote usability evaluation which complements the methodology commonly used in this research area.
Filtering usability data with reference to behavior
2011
No company can stay in business without having a "useful" web presence. The question is how usefullnes can be achieved. Usefullnes in this sense is how attractive and useful it is for the visitors. This can be done by observing the visitors' behavior. Doing this through interviews and observation of users in their living rooms is expensive and in many cases even impractical. So, other means need to be found. This paper presents a tool for the evaluation of usefulness of a web presence by extracting and analyzing information out of its log files. The information extraction can be refined using a set of filters which can be arbitrarily combined by the usability engineer responsible for mainta…
FATIGUE LIFE ANALYSIS OF RAIL-WELDS USING LINEAR ELASTIC FRACTURE MECHANICS
2019
The initiation and growth of fatigue cracking is mainly due to high stress concentration, heterogeneity and poor quality of weld. The detection and rectification of such weld defects are major concerns of rail network managers to reduce potential risk of rail breaks and derailments. To estimate the fatigue life of welded joints and to analyze the progress of fatigue cracks, a fracture mechanics-based analysis and fatigue models were developed using Finite Element Analysis. The initial flaw is obtained from a sample weld using ultrasonic flaw detecting machine test. Linear Elastic Fracture Mechanics (LEFM) approach based on the Paris law was applied to determine critical crack size and the n…
Digitization and characterization of local reflectance of complex surfaces for visual inspection
2022
Mastering the visual perception of the surfaces of manufactured products is a central issue for industry. However, in industry, the quality of surfaces is often assessed by human inspectors. Only a few specific cases use an instrumental or photometric approach. Among the photometric approaches, one of them is experiencing significant growth: Reflectance Transformation Imaging (RTI). The RTI makes it possible to obtain a reduced and simplified estimate of the Bidirectional Reflectance Distribution Function (BRDF) and an estimate of the geometry of the surface. However, this technique has limitations in terms of data acquisition and processing. The objective is therefore to correct some of th…