Wyniki wyszukiwania - BazTech

1

Effective telematics application of wireless and fiber bragg grating sensors for structural health monitoring of tall buildings

Saidov K., Szpytko J.

Archives of Transport System Telematics

|

2015

|

Vol. 8, iss. 3

35--40

EN

In recent years, there has been an increasing interest in the adoption of emerging sensing technologies for instrumentation within a variety of structural systems in civil and building engineering. Wireless and fiber bragg grating sensors are emerging as sensing paradigms that the structural engineering field has begun to consider as substitutes for traditional tethered monitoring systems. A benefit of each sensors structural monitoring systems is that they are inexpensive to install because extensive wiring is no longer required between sensors and the data acquisition system. Researchers has been discovering that wireless and fibber bragg grating sensors are an exciting technology that should not be viewed as simply a substitute for traditional tethered monitoring systems. Rather, these sensors can play greater roles in the processing of structural response data; this feature can be utilized to screen data for signs of structural damage. Also, sensors have limitations that require novel system architectures and modes of operation. This paper is intended to present a summary review of the collective experience the structural engineering community has gained from the use of wireless and fiber bragg grating sensors for monitoring structural performance and health of tall type buildings.

2

Nonparametric identification of added masses in frequency domain: a numerical study

Suwała G., Biczyk J., Jankowski Ł.

IPPT Reports on Fundamental Technological Research

|

2013

|

nr 4

37--41

EN

This paper presents a theoretical derivation and reports on a numerical verification of a model-free method for identification of added masses in truss structures. No parametric numerical model of the monitored structure is required, so there is no need for initial model updating and fine tuning. This is a continuation and an improvement of a previous research that resulted in a time-domain identification method, which was tested to be accurate but very time-consuming. A general methodology is briefly introduced, including the inverse problem, and a numerical verification is reported. The aim of the numerical study is to test the accuracy of the proposed method and its sensitivity to various parameters (such as simulated measurement noise and decay rate of the exponential FFT window) in a numerically controlled environment. The verification uses a finite element model of the same real structure that was tested with the time-domain version of the approach. A natural further step is a lab verification based on experimental data.

3

Novelty detection based on elastic wave signals measured by different techniques

Nazarko P., Ziemiański L.

Computer Assisted Methods in Engineering and Science

|

2012

|

Vol. 19, no. 4

317-330

EN

The paper discusses the results of laboratory experiments i n which three independent measurement techniques were compared: a digital oscilloscope, phased array acquisition system, a laser vibrometer 3D. These techniques take advantage of elastic wave signals actuated and sensed by a surface-mounted piezoelectric transducers as well as non-contact measurements. In these e xperiments two samples of aluminum strips were investigated while the damage was modeled by drilling a hole. The structure responses recorded were then subjected to a procedure of signal processing, and features’ extraction was done by PrincipalComponents Analysis. A pattern database defined was used to train artificial neural networks for the purpose of damage detection.

4

Structural health monitoring - a review with the emphasis on low-frequency methods

Kołakowski P.

Engineering Transactions

|

2007

|

Vol. 55, iss. 3

239-275

EN

Structural Health Monitoring (SHM) is a fast-developing, interdisciplinary field of research having its roots in vibroacoustics and non-destructive testing and evaluation. Fast development of the area is due to the fact that SHM is heavily stimulated by the engineering problems of maintenance and safe operation of technical infrastructure. The use of SHM is slowly becoming a standard in high-cost, modern infrastructure. Therefore, the possibility of application should always be on the horizon of any related research work. Thus far, the majority of SHM applications have been demonstrated in civil, aerospace and mechanical engineering. This paper reviews the main achievements and points out the current trends in this field with the emphasis on low-frequency methods.

5

Smart sensor solutions for mechanical measurements and diagnostics

Bojko T.

Metrology and Measurement Systems

|

2005

|

Vol. 12, nr 1

95-105

EN

Application of many sensors located on a mechanical structure causes serious technical problems. One of the main problems is wiring of sensors which is time-consuming and may change the system output due to high structure loading and damping. To overcome this problem new smart sensor designs have been proposed. One of the most promising technologies in this field is wireless data transfer. In the paper requirements for the developed smart wireless sensor are specified. The important part of a smart sensor is the transducer which transforms certain information from the physical world to user defined values - mostly the voltage. In the paper the application of industrial accelerometers was specified and descriptions of basic types of accelerometers are given. For smart sensor design two modern embedded accelerometers were specified and laboratory-tested.

PL

Współczesne systemy diagnostyczne i monitorujące wymagają zastosowania wielu czujników, co często wywołuje wiele problemów natury technicznej. Głównym problemem jest odpowiednie wykonanie okablowania zainstalowanych czujników w sposób, który nie wpłynąłby na zmianę parametrów konstrukcji i jednocześnie był optymalny z punktu widzenia charakterystyk połączeń elektrycznych. Montaż przewodów sygnałowych w wielu przypadkach jest również utrudniony, a sygnał jest narażony na wpływ zakłóceń o różnym charakterze. Jednym z rozwiązań, które mogą uprościć i ułatwić instalację takicj złożonych systemów diagnostycznych jest zastosowanie bezprzewodowej transmisji danych. W artykule opisano strukturę i wymagania nowoczesnego bezprzewodowego czujnika drgań projektowanego w KRiDM AGH przeznaczonego do diagnostyki układów mechanicznych. Jednym z kluczowych elementów projektowanego czujnika drgań jest akcelerometr. W artykule opisano dwa zaawansowane czujniki drgań ADXL202 i P3BXN, które zostały poddane szeregowi testów laboratoryjnych mających na celu określenie ich przydatności do budowy inteligentnego czujnika. Załączone w artykule wyniki pomiarów są pomocne w zorientowaniu się o właściwościach metrologicznych prezentowanych czujników.

6

New hardware solutions for structural health monitoring

Uhl T., Bojko T.

Pomiary Automatyka Kontrola

|

2004

|

R. 50, nr 5

9-12

EN

Nowadays, research concerning applications of structural health monitoring has aroused a great interest. SHM methods are applied to condition monitoring of machines and structures, structural integrity assessment, damage detection and structural failure prevention. Measurement data acquired by the use of different sensors and data acquisition systems is essential for SHM. The most popular SHM algorithms require vibration measurements, which arise difficulties resulting from the analysis of signals from many sensors. In the paper, newly developed hardware solutions for the SHM application are presented. In accordance with the defined requirements, the design of CAN based accelerometer module is shown.

PL

Współczesnie dużego znaczenia nabierają prace związane z praktyczną realizacją systemów do monitorowania stanu konstrukcji. Metody aktywnego monitorowania znajdują zastosowanie do badania maszyn i struktur mechanicznych, badań strukturalnych, detekcji zniszczenia, zapobiegania stanom awaryjnym. W systemach monitorujących najczęściej analizowane są drgania konstrukcji. Uzyskanie prawidłowych wyników zależy od sposobu akwizycji danych pomiarowych, co w przypadku analizy sygnałów z wielu czujników nie jest zadaniem prostym. W artykule opisano konstrukcję inteligentnego modułu akcelerometru zbudowanego z zastosowaniem układów MEMS i wyposażonego w interfejs magistrali CAN.