Assessing material densities by vibration analysis and independent component analysis


  • Hajar Razaghi
  • Reza Saatchi
  • Amaka Offiah
  • Derek Burke
  • Nick Bishop
  • Santosh Gautam



Density assessment, Vibration analysis, Independent component analysis,


The aim of this study was to investigate vibration analysis and independent component analysis (ICA) to assess the density of multiple materials making up a single structure. Density is important as it reveals information about physical properties of materials. The density of a single material can be determined from the relationship between its mass and volume. However, when a structure consists of multiple materials, identification of their individual densities from the structure is complicated. Vibration analysis is a technique that reveals information about an object’s physical properties such as its density. The investigation was carried out using a plastic test tube filled separately with three liquids of known densities; water, Chloroform and Methanol. Vibration was inducted into the tube, through an electronic system that produced a single impact at a predefined location on the tube. The resulting vibration signals were recorded using two vibration sensors placed on the tube. A signal source separation technique called ICA was used to obtain the vibration effects of the liquid and the tube. The power spectral densities (PSD) of ICA extracted vibration signals were examined. The frequency of the largest peak in the PSD was related to the liquid’s density under test. The study indicated that vibration analysis may be effective in assessing materials’ densities in a structure that contains multiple materials, however a larger study is needed to explore the findings.


S.A. Neild, P.D. McFadden, M.S. Williams, Engineering Structures, 2003,vol.25, pages 713–728.

T.C. Tsai and Y. Z. Wang, Journal of Sound and Vibration", 1996, vol. 192, no.3, pages 607-620.

S. Ebersbach, Z. Peng, Expert Systems with Applications, 2008, vol. 34, pages 291–299.

A. Hyva¨rinen, E. Oja, Neural Networks, 2000, vol.13, issues 4-5, pages 411-430.

J. V. Stone, Trends in Cognitive Sciences. 2002, vol.6, issue 2, pages 59-64.

A. J.Bell and T.I. Sejnowski , Neural Computation 1995, vol. 7, pages 1129-1159.

M. J. Roan, J. G. Erling and L. H. Sibul, Mechanical Systems and Signal Processing 2002, vol. 16, no.5, pages 719–740.

J. Antoni, Mechanical Systems and Signal Processing, 2005, vol.19,pages 1166–1180.

G. Kerschen, F. Poncelet, J.-C. Golinval, Mechanical Systems and Signal Processing, 2007, vol. 21, pages1561–1575.

G. Gelle, M. Colas and G. Delaunay , Mechanical Systems and Signal Processing, 2000,vol. 14, no.3, pages 427-442.