Inspection | EPFL Graph Search

An inspection is, most generally, an organized examination or formal evaluation exercise. In engineering activities inspection involves the measurements, tests, and gauges applied to certain characteristics in regard to an object or activity. The results are usually compared to specified requirements and standards for determining whether the item or activity is in line with these targets, often with a Standard Inspection Procedure in place to ensure consistent checking. Inspections are usually non-destructive. Inspections may be a visual inspection or involve sensing technologies such as ultrasonic testing, accomplished with a direct physical presence or remotely such as a remote visual inspection, and manually or automatically such as an automated optical inspection. Non-contact optical measurement and photogrammetry have become common NDT methods for inspection of manufactured components and design optimisation. A 2007 Scottish Government review of scrutiny of public services (th

Miniature Magnetic Climbing Inspection Robots

Frédéric Rochat

Industrial plants have an abundance of complex and confined areas that require systematic inspection. Maintenance work is necessary to ensure reliability and safety. In many cases, due to either size limitations or high danger, access is impossible to humans. Current inspections require long and costly dismounting or safety procedures. Robotic inspection could be a convenient solution to overcome the lack of accessibility and safety for human inspectors. In the energy industry for instance, where downtime can cost millions of dollars per day, dedicated and agile robots may pursue inspection faster than humans, thus reducing the duration of overhaul. Additionally, robotic inspection may offer higher repeatability and reliability compared to human inspection. Distraction or simply boredom caused by repetitive tasks may result in an incomplete or failed inspection. Moreover, social costs and the hardness of working in an unfriendly or even toxic environment may be reduced. This work focuses on adhesion analysis, integration and mobility extension of miniature climbing robots for industrial applications. Existing solutions were carefully analysed in order to propose an innovative technology and methodology to be used in the design and implementation of these robots. The main objective was to increase the availability, capability and use of mobile robots for inspection in complex industrial environments. Due to the reduced dimensions of the industrial areas to be inspected, in some cases less than 25 mm, miniaturisation of the robot was required, as well as high mobility in 3D complex environments. Climbing ability is enhanced by improving adhesion techniques and their synergy with locomotion. Ferromagnetic environments are common in industrial facilities. Since magnetic adhesion is superior to other methods, a major effort of this work has been devoted to methodically understand and improve the use of permanent magnets as adhesion and magnetization devices integrated into miniature climbing inspection robots. Implementation of the magnetic adhesion was achieved in different magnetic climbing robots with locomotion principles such as wheels, caterpillars or feet. An innovative obstacle passing mechanism was proposed with the Cy-mag3D robots family. A proposed approach is the use of a Magnetic Switchable Device (MSD) as an adhesive and magnetizing device for inspection robots. Results show that the energy efficiency of MSDs is higher when compared to the vertical mechanical detachment of a system with permanent magnets or an electromagnetic system. MSDs have been used in TUBULO, an inchworm for visual inspection of boiler tubes of 25 mm in diameter, and TREMO, a climbing inchworm for visual inspection of complex ferromagnetic environments. A novel MSD configuration was proved adequate to perform Magnetic Particle Inspection (MPI). This work proposes novel solutions to realise miniature magnetic climbing robots dedicated to inspection. The proven results go beyond the anterior state of the art. Accordingly, inspection robots may move with versatility in industrial environments. The outcome of this work opens new perspectives for the use of mobile climbing robots with direct application in industrial inspection.

EPFL2011

TbCAPs: A toolbox for co-activation pattern analysis

Eva Blondiaux, Thomas William Arthur Bolton, Farnaz Delavari, Herberto Dhanis Pedro De Barros Camacho, Baptiste Gauthier, Julian Gaviria, Elenor Morgenroth, Gwladys Rey, Lukasz Dawid Smigielski, Constantin Tuleasca, Dimitri Nestor Alice Van De Ville

Functional magnetic resonance imaging provides rich spatio-temporal data of human brain activity during task and rest. Many recent efforts have focussed on characterising dynamics of brain activity. One notable instance is co-activation pattern (CAP) analysis, a frame-wise analytical approach that disentangles the different functional brain networks interacting with a user-defined seed region. While promising applications in various clinical settings have been demonstrated, there is not yet any centralised, publicly accessible resource to facilitate the deployment of the technique. Here, we release a working version of TbCAPs, a new toolbox for CAP analysis, which includes all steps of the analytical pipeline, introduces new methodological developments that build on already existing concepts, and enables a facilitated inspection of CAPs and resulting metrics of brain dynamics. The toolbox is available on a public academic repository at http://c4science.ch/source/CAP_Toolbox.git. In addition, to illustrate the feasibility and usefulness of our pipeline, we describe an application to the study of human cognition. CAPs are constructed from resting-state fMRI using as seed the right dorsolateral prefrontal cortex, and, in a separate sample, we successfully predict a behavioural measure of continuous attentional performance from the metrics of CAP dynamics (R = 0.59).

ACADEMIC PRESS INC ELSEVIER SCIENCE2020

Automatic detection of generalized paroxysmal fast activity in interictal EEG using time-frequency analysis

Amir Hossein Omidvarnia

Objective: Markup of generalized interictal epileptiform discharges (IEDs) on EEG is an important step in the diagnosis and characterization of epilepsy. However, manual EEG markup is a time-consuming, subjective, and the specialized task where the human reviewer needs to visually inspect a large amount of data to facilitate accurate clinical decisions. In this study, we aimed to develop a framework for automated detection of generalized paroxysmal fast activity (GPFA), a generalized IED seen in scalp EEG recordings of patients with the severe epilepsy of Lennox-Gastaut syndrome (LGS). Methods: We studied 13 children with LGS who had GPFA events in their interictal EEG recordings. Timefrequency information derived from manually marked IEDs across multiple EEG channels was used to automatically detect similar events in each patient's interictal EEG. We validated true positives and false positives of the proposed spike detection approach using both standalone scalp EEG and simultaneous EEG-functional MRI (EEG-fMRI) recordings. Results: GPFA events displayed a consistent low-high frequency arrangement in the time-frequency domain. This 'bimodal' spectral feature was most prominent over frontal EEG channels. Our automatic detection approach using this feature identified EEG events with similar time-frequency properties to the manually marked GPFAs. Brain maps of EEG-fMRI signal change during these automatically detected IEDs were comparable to the EEGfMRI brain maps derived from manual IED markup. Conclusion: GPFA events have a characteristic bimodal time-frequency feature that can be automatically detected from scalp EEG recordings in patients with LGS. The validity of this time-frequency feature is demonstrated by EEG-fMRI analysis of automatically detected events, which recapitulates the brain maps we have previously shown to underlie generalized IEDs in LGS. Significance: This study provides a novel methodology that enables a fast, automated, and objective inspection of generalized IEDs in LGS. The proposed framework may be extendable to a wider range of epilepsy syndromes in which monitoring the burden of epileptic activity can aid clinical decision-making and faster assessment of treatment response and estimation of future seizure risk.

PERGAMON-ELSEVIER SCIENCE LTD2021