K.M.Khaled, G.Aggag, A.E.Abuelezz, M.G.Elsherbiny
A new design of 3 kN·m reference torque standard machine was considered. The machine performance is evaluated via inter-laboratory comparison technique using previously calibrated reference torque transducers, one set at the National physical laboratory of Germany (PTB) and the other one calibrated at the accredited laboratory of the English company Norbar. Two loading schemes are used. The first one is slow (5 minutes per calibration step) while the second is a fast one (45 seconds per calibration step). The calibration results revealed good agreement between the designed machine and those...
TC3 Conference 2010
· TC3
· 2010
· Download
Yu-Chung Huang, Jiun-Kai Chen, Hsin-Chia Ho, Chung-Sheng Tu, Chao-Jung Chen
This paper mainly describes Taiwan's metrology NML (National Measurement Laboratory) to set up and evaluate a shock accelerometer calibration system which follows the ISO 16063-13:2001 standard. The environmental shock testing of electro-acoustics or electronic spare parts, the product packing falling impact, the automobile collision and the helmet impact test and so on are more and more important for quality and safety. In consideration of that, NML has started to establish the primary shock calibration system which calibrates the accelerometer sensitivity and trace to the metric unit since...
TC22 Meeting 2010
· TC22
· 2010
· Download
Holger Nicklich, Uwe Bühn, Heiko Deierlein, Frank Schulz, Michael Mende
It is mandatory that for every calibration system intended for the determination of the complex transfer coefficients of vibration sensors, the phasefrequency response of its electronic subunits is determined and the total system is calibrated in its entirety. Since currently no national metrological institution is equipped with the necessary measurement facilities, a research project was carried out jointly by the SPEKTRA GmbH Dresden, Germany, and PTB, the German metrological institute, in the context of which such instrumentation was developed, constructed, and linked to the German...
TC22 Meeting 2010
· TC22
· 2010
· Download
Gustavo P. Ripper, Cauê D. Ferreira, Dimas B. Teixeira, Ronaldo S. Dias, Giancarlo B. Micheli
This paper presents a primary interferometric calibration system that was developed in the Vibration Laboratory at INMETRO for the calibration of vibration transducers and measuring instruments at low frequencies. This system is based on a long-stroke air bearing shaker, and on a data acquisition board. It has been used for calibration of accelerometers and servo-accelerometers within the frequency range from 0.4 Hz to 160 Hz. Optionally, the system can be adapted to calibrate laser vibrometers for their further use as comparison reference transducers. Fully automated calibrations are...
TC22 Meeting 2010
· TC22
· 2010
· Download
Wan-Sup Cheung, Tae-Ik Park
This paper introduces a new 'portable' angular exciter model developed in KRISS during last two years. Its development was successfully completed in 2010 such that most technical issues have been resolved and a product model is ready to be delivered to the industrial sectors. Interestingly, a new company being incubated in KRSSS emerged to make and distribute a final version of angular vibration exciters to the market. This paper introduces recent measurement and test results, such as the usable frequency range, the capacity of generating angular acceleration, harmonic distortion ratios,...
TC22 Meeting 2010
· TC22
· 2010
· Download
Qiao Sun, Chenguang Cai
In this paper, the shortcomings and their causes of the conventional homodyne time interval analysis (TIA) method is described with respect to its software algorithm and hardware implementation, based on which a simplified TIA method is proposed with the help of virtual instrument technology. Equipped with an ordinary Michelson interferometer and dual channel synchronous data acquisition card, the primary vibration calibration system using the simplified method can perform measurements of complex sensitivity of accelerometers accurately, meeting the uncertainty requirements laid down in...
TC22 Meeting 2010
· TC22
· 2010
· Download
Thomas Bruns, Frank Blume, Kai Baaske, Mark Bieler
For the primary calibration of the phase response of accelerometers, the knowledge of the response delay of the reference, i.e. the laser interferometer is a decisive prerequisite. However, an experimental determination of the interferometric response time is not a simple task. This contribution describes an opto-electronic set-up based on a femtosecond laser and originally developed for calibration of high speed sampling oscilloscopes, which enables a precise determination of the intrinsic delay of the photo detectors of a modified Michelson interferometer used at PTB.
TC22 Meeting 2010
· TC22
· 2010
· Download
N.Ruetaiworraseth, W.Suntiamorntut, B.Thummawut, P. Rattanangkul
This paper presents a wireless sensor network technology for low frequency vibration monitoring system. Sensor node collects the data from accelerometer and transmits the data back to base station through wireless communication. The data has been computed and converted into acceleration information that is stored in database. Then users can monitor using a web application. The experiments were carried out by collecting the acceleration data from three-axis accelerometer. The data from each axis was measured and verified by vertically aligning with a Very Low Frequency Primary Calibration...
TC22 Meeting 2010
· TC22
· 2010
· Download
Richard W. Bono, Eric J. Seller, Mark I. Schiefer
ISO 16063 part 21 defines the back-to-back comparison technique for accelerometer calibration. Included in its most recent revision is a recommendation for acceptable limits on shaker transverse motion characteristics. The effect of high transverse inputs can be devastating to accurate accelerometer calibration. This paper discusses the differences between mechanical flexurebased electrodynamic shakers and air bearing shakers and the resulting effects on calibration accuracy and uncertainty.
TC22 Meeting 2010
· TC22
· 2010
· Download
Hideaki Nozato, Takashi Usuda, Akihiro Oota, Seiji Okamoto, Ken Yamamoto, Hiroshi Unejima, Kazuaki Kawaguchi, Ishigami Tamio
Shock acceleration measurements are required for evaluating product drop tests and automobile collision tests, and the need for precise shock acceleration measurements continue to increase in the Japanese industries. Thus, it is important to confirm the equivalence of measurement technology among manufacturing corporations, private testing laboratories and national metrology institutes. For this purpose, a round robin test of shock acceleration calibration was carried out among the two Japanese private laboratories (“Foresight Techno”, “Shinyei Technology”) and the National Metrology...
TC22 Meeting 2010
· TC22
· 2010
· Download