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Wojciech Toczek, Michal Kowalewski, Romuald Zielonko
HISTOGRAM-BASED FEATURE EXTRACTION TECHNIQUE APPLIED FOR FAULT DIAGNOSIS OF ELECTRONIC CIRCUITS

In this paper we discuss and compare two feature extraction techniques: histogram-based and Principal Component Analysis. Comparison is done on an analog filter fault diagnosis example performed in the frequency domain. Both techniques are implemented in a neural network system for the off-line diagnosis of electronic analog and mixed-signal circuits. The numerical and experimental examples of frequency domain ANN-based testing of filter are presented to demonstrate the usefulness of the histogram approach.

Romuald Zielonko, Marek Niedostatkiewicz
TIME DOMAIN DIAGNOSIS OF ANTICORROSION COATINGS VIA SHAPE DESIGNED MEASUREMENT SIGNALS

The paper presents time domain diagnostic method of anticorrosion coating on the level of equivalent circuit parameter identification. The method is based on applying non-conventional, shape-designed stimuli signals and measuring the object responses (so-called observables) at a given time T. Equivalent circuit parameters are calculated directly from observables using analytical equations, determinated by modelling circuit topology. In the paper the theoretical basis of the method is presented, together with measurement methodology and simulation results for 4 elements anticorrosion coating equivalent circuit.

Kimmo Yliniemi, Jan van Deventer, Jerker Delsing
SENSOR FAULT DETECTION IN A DISTRICT HEATING SUBSTATION

This paper describes a method to detect temperature sensor faults in a district-heating substation (DHS). It uses valve position monitoring and variance monitoring to detect sensor faults. Depending on user requirements the method can be customized to either detect faults fast or to have a low false alarm rate and being able to detect smaller noise increases but at the expense of longer detection time. The result is a method that uses a limited amount of computing power, which does not require much computing precision since the only computing done is addition of integers and is therefore suitable for implementation in a microcontroller.

Kimmo Latva-Käyrä, Risto Ritala
SENSOR DIAGNOSTICS BASED ON DYNAMIC CHARACTERISTIC CURVE ESTIMATION

This paper presents a method for optimal detection of need for re-estimation of the parameters of characteristic curves based on infrequent and irregular reference measurements. We assume that the validity of parameters deteriorates through a stochastic process. In particular, we give analytic distributions of parameters when deterioration is through random-walk diffusion. The detection of need for re-estimation of parameters is similar to two-variable Statistical Process Control scheme. Method is demonstrated and its detection capabilities analyzed in cases where the actual deterioration is either a step change, a linear drift or a random walk.

Guy A. E. Vandenbosch
HIGH FREQUENCY ELECTROMAGNETIC FIELD SENSORS AND SMALL, INTEGRATED ANTENNAS: CHALLENGES FOR THE FUTURE

In this educational overview paper it is shown that the traditional distinction between on the one hand ElectroMagnetic (EM) field sensors and on the other hand “antennas” is slowly disappearing at higher frequencies. First a definition of both components is given. Second, the fundamental difference between both components is discussed. Third, it is shown that at very high frequencies, both definitions actually “merge”, resulting in a single component. The fact that in practise, higher and higher frequencies are indeed used in many applications should invoke an intense cooperation between the two research communities, the one involved in the analysis and design of EM sensors, and the one involved in the analysis and design of antennas. Also, the modeling tools used in both communities are based on the same fundamental principles. Cooperation there is also of mutual interest. The current trends and challenges for the future are discussed briefly. During the presentation, they will be addressed extensively.

Wojciech Cholewa
IDENTIFICATION OF RELEVANT SIGNAL FEATURES

The paper deals with design of diagnostic classifiers. The main goal is to illustrate an original way of identification of useful signal features on the basis of learning data prepared as a set of examples. One indicated some possibilities of application of a criterion based on the expectation that results of unsupervised clustering in a new limited space should be compatible with results of classification of learning data.

Heinrich Schwenke, Christina Warmann
HIGH SPEED HIGH ACCURACY MULTILATERATION SYSTEM BASED ON TRACKING INTERFEROMETERS

The use of tracking interferometers has gained industrial application for the testing and the calibration of measuring and production machines. The concept is based on sequential multilateration and can realize calibration uncertainties in the sub-micron order. Another application for tracking interferometers is the real-time multilateration for accurate and highly dynamic measurement of 3D motion. This paper presents the characteristics of a high speed high accuracy multilateration system based on interferometric displacement measurements.

Sebastian Strube, Gabor Molnar, Hans-Ulrich Danzebrink
COMPACT FPGA BASED MULTI-AXIAL INTERFEROMETER APPLIED IN A METROLOGICAL ATOMIC FORCE MICROSCOPE

For use in a new, metrological atomic force microscope (AFM) a highly compact interferometer, based on a modified homodyne Twyman-Green interferometer concept was developed at PTB. It is modular, measures displacement and tilt simultaneously, allows for traceability and an uncertainty in the Ångstrom range. A novel signal processing approach based on a field programmable gate array (FPGA) is employed, whereby a spatial interferogram is acquired by a high-speed line sensor and transformed into its frequency spectrum through a discrete Fourier transform. The AFM combines an FPGA for preprocessing, a digital signal processor (DSP) which runs the AFM control algorithm and a general purpose processor (GPP) for user-interface handling and mass data storage. The complete system allows for implementing a multitude of different AFM measuring modes, e.g. contact mode, intermittent contact mode using amplitude detection and phase detection or frequency tracking mode.

T. Hausotte, B. Percle, N. Vorbringer-Dorozhovets, H. Baitinger, F. Balzer, U. Gerhardt, E. Manske, G. Jäger, D. Dontsov
INTERFEROMETRIC MEASURING SYSTEMS OF NANOPOSITIONING AND NANOMEASURING MACHINES

The Nanopositioning and Nanomeasuring Machine (NMM-1) developed at the Ilmenau University of Technology is equipped with three homodyne plane-mirror miniature interferometers for the measurement of the displacement of a movable corner mirror. The object being measured is placed on the corner mirror, which is positioned by a three-axis drive system. The probing system and the plane-mirror miniature interferometers are fixed on a metrology frame made of Zerodur®. Depending on the selected probing system, the machine is capable of carrying out both 2½D surface scans and 3D coordinate measurements. In this way objects can be measured or scanned in volumes up to 25 mm × 25 mm × 5 mm with nanometre precision using various optical and tactile probe systems.

Frank Härtig, Matthias Franke, Karin Kniel, Klaus Wendt
COORDINATE MEASUREMENT TECHNIQUE CONSIDERING THE 3D-ABBE PRINCIPLE

A new portable measuring machine for three-dimensional measurements has been developed and verified for high-accurate inspection and calibration of large parts directly onsite in production. The system can be considered as a high-precision metrological frame. It is capable to improve the accuracy of conventional coordinate measuring machines (CMMs) or can turn machine centres into qualified 3D measuring devices. In general this procedure is applicable to multi-body systems used to move a tool mounted at the last kinematic axis, for instance, CMMs, machine tools or robots. The core tasks in achieving this system are based to a large extent on the successes of: M3D3 algorithms that control the system and task specific error correction that the system offers. Tasks involved were jointly implemented by PTB.

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