A generalised multiple-mass based method for the determination of the live mass of a force transducer.

Montalvão, D., Baker, T., Ihracska, B. and Aulaqi, M., 2016. A generalised multiple-mass based method for the determination of the live mass of a force transducer. Mechanical Systems and Signal Processing.

Full text available as:

[img]
Preview
PDF
1-s2.0-S0888327016302072-main.pdf - Published Version
Available under License Creative Commons Attribution.

1MB

DOI: 10.1016/j.ymssp.2016.06.028

Abstract

Many applications in Experimental Modal Analysis (EMA) require that the sensors' masses are known. This is because the added mass from sensors will affect the structural mode shapes, and in particular its natural frequencies. EMA requires the measurement of the exciting forces at given coordinates, which is often made using piezoelectric force transducers. In such a case, the live mass of the force transducer, i.e. the mass as 'seen' by the structure in perpendicular directions must be measured somehow, so that compensation methods like mass cancelation can be performed. This however presents a problem on how to obtain an accurate measurement for the live mass. If the system is perfectly calibrated, then a reasonably accurate estimate can be made using a straightforward method available in most classical textbooks based on Newton's second law. However, this is often not the case (for example when the transducer's sensitivity changed over time, when it is unknown or when the connection influences the transmission of the force). In a self-calibrating iterative method, both the live mass and calibration factor are determined, but this paper shows that the problem may be ill-conditioned, producing misleading results if certain conditions are not met. Therefore, a more robust method is presented and discussed in this paper, reducing the ill-conditioning problems and the need to know the calibration factors beforehand. The three methods will be compared and discussed through numerical and experimental examples, showing that classical EMA still is a field of research that deserves the attention from scientists and engineers.

Item Type:Article
ISSN:0888-3270
Uncontrolled Keywords:Experimental Modal Analysis; Force transducer; Calibration; Live mass
Subjects:UNSPECIFIED
Group:Faculty of Science & Technology
ID Code:24562
Deposited By: Unnamed user with email symplectic@symplectic
Deposited On:24 Aug 2016 14:21
Last Modified:24 Aug 2016 14:21

Downloads

Downloads per month over past year

More statistics for this item...
Repository Staff Only -