Quantification of the uncertainties of high-speed camera measurements

Abstract

Abstract. This article proposes a combined theoretical and experimental approach to assess and quantify the global uncertainty of a high-speed camera velocity measurement. The study is divided in five sections: firstly, different sources of measurement uncertainties performed by a high-speed camera are identified and quantified. They consist of geometrical uncertainties, pixel discretisation uncertainties or optical uncertainties. Secondly, a global uncertainty factor, taking into account the previously identified sources of uncertainties, is computed. Thirdly, a sensibility study of the camera set-up parameters is performed, allowing the experimenter to optimize these parameters in order to minimize the final uncertainties. Fourthly, the theoretical computed uncertainty is compared with experimental measurements. Good concordance has been found. Finally, the velocity measurement uncertainty study is extended to continuous displacement measurements as a function of time. The purpose of this article is to propose all the mathematical tools necessary to quantify the individual and global uncertainties, to highlight the important aspects of the experimental set-up, and to give recommendations on how to improve a specific set-up in order to minimize the global uncertainty. Taking all these into account, it has been shown that highly dynamic phenomena such as a ballistic phenomenon can be measured using a high-speed camera with a global uncertainty of less than 2%.

Dynamic calibration of piezoelectric transducers for ballistic high-pressure measurement

“…Also, special attention was devoted to the problem of lighting to ensure a high quality measurement. A thorough explanation of the velocity computing based on the HSC measurement was performed by Robbe et al [16].…”

“…The simultaneous measurement certainly improves the results. However, only the HSC was used to achieve the defined purpose especially as the HSC measurement uncertainties could be computed [16].…”

“…Here, the elementary uncertainties u(x i ) are supposed to be independent and approximately linear. As mentioned above, the calculation of the displacement and its measurement uncertainty were performed by a dedicated program [16]. Individual uncertainties were computed and the global uncertainty was determined precisely.…”

Traceability validation of a high speed short-pulse testing method used in LED production

“…The ambient temperature uncertainty component under pulsed operation is estimated to be at the level of 0.5%. The total measurement uncertainty of the optical power of the DUT, U(P i ), is estimated using the generalized equations (4) and (5) from [13] and the estimated individual uncertainty components from Table 8.…”

“…The scaling factor x i is determined by the next three equations (10)- (12) and the absolute spectrally dependent current by equation (13) using numerical integration in the measurement region of wavelengths between l min and l max :…”