Logo of the Physikalisch-Technische Bundesanstalt

Analysis of dynamic measurements

Working Group 8.42

Overview

Dynamic measurements can be found in many areas of metrology and industry such as, for instance, in the measurement of time-dependent forces or accelerations. Methods from signal processing are often applied in the analysis of dynamic measurements. In many applications linear time-invariant systems are appropriate to model dynamic measurements, where the output signal is obtained as a convolution of the input signal and the measurement system’s impulse response. Input and output signal are not proportional to each other, and estimation of the system’s input signal from its output signal constitutes one important task in the analysis of dynamic measurements. Often digital filters are employed for this purpose. The evaluation of the uncertainty associated with the estimated input signal is particularly important from a metrological perspective.

Typical dynamic measurement with time-dependent errors in the output signal caused by the dynamic behavior of the measurement system.

Typical examples are measurements of mechanical quantities as, for example, force, torque and pressure. Further examples are oscilloscope measurements for the characterization of high speed electronics, hydrophone measurements for the characterization of medical ultrasound devices, the spectral characterization of radiation sources, spectral color measurements and camera-aided temperature measurements.

 

Research

One focus of PTB‘s Working Group 8.42 is the development of methods for the estimation of the input signal from the output signal when the dynamic behavior of the measurement system has been characterized. This includes the development of procedures for the evaluation of the uncertainty associated with the estimated input signal. Another focus is the development of methods for the analysis of dynamic calibration measurements aimed at determining the dynamic behavior of a measurement system.

Software

Publications

Publication single view

Article

Title: Investigations for the model-based dynamic calibration of force transducers by using shock excitation
Author(s): M. Kobusch, S. Eichstädt, L. Klaus and T. Bruns
Journal: ACTA IMEKO
Year: 2015
Volume: 4
Issue: 2
Pages: 45-51
File URL: fileadmin/internet/fachabteilungen/abteilung_8/8.4_mathematische_modellierung/Publikationen_8.4/ACTA_IMEKO_2014_Kobusch_et_al_preprint.pdf
Web URL: http://acta.imeko.org/index.php/acta-imeko/article/view/IMEKO-ACTA-04%20%282015%29-02-08/384
Keywords: model-based dynamic calibration, dynamic calibration, dynamic modelling,editor,force transducers, imeko
Tags: 8.42, Dynamik
Abstract: Within the scope of the joint research project EMRP IND09 “Traceable dynamic measurements of mechanical quantities”, numerous measurements were performed at PTB’s 20 kN primary shock force calibration device to investigate and validate the approach of a model-based dynamic calibration of force transducers by using shock excitations. The tests included several strain gauge force transducers of greatly differing structural design, size, weight and mechanical coupling. By looking at a few examples, some investigated physical models of the measurement set-up and a developed data analysis procedure for parameter identification based on measured shock data are presented and discussed. The models reproduce the dynamic response including the observed modal oscillations of various origins that limit the usable measurement bandwidth. Moreover, these modal oscillations may have an important role for the parameter identification process, which is further discussed. This paper is an extended version of the original contribution to the IMEKO 2014 conference in Cape Town, South Africa.
Note: Open Access

Back to the list view

To top