Authors: Nuria Sáez; Josefina Gavaldà; Xavier Ruiz; Valentina Shevtsova
Addresses: Department of Chemical Physics and Inorganic, Universitat Rovira i Virgili, Tarragona, Spain ' Department of Chemical Physics and Inorganic, Universitat Rovira i Virgili, Tarragona, Spain ' Department of Chemical Physics and Inorganic, Universitat Rovira i Virgili, Tarragona, Spain ' Department of Chemical Physics, MRC, Université Libre Bruxelles, Brussels, Belgium
Abstract: The aim of this work is to study the vibrational impact of the shaker during a past European Space Agency (ESA) experiment. To do so, we have analysed four accelerometric signals downloaded from the National Aeronautics and Space Administration (NASA) and Principal Investigator Microgravity Services (PIMS) website. The first two ones came from the sensor located in the Columbus module and correspond to time periods in which the shaker is inactive or active respectively. The other two came from the Destiny Laboratory and covers the above mentioned different time intervals. The results obtained indicate that the spectral fingerprints of the shaker are weakly present in the signals gathered from Destiny Laboratory. In addition, the consideration of all histograms shows that the shaker modifies the normal distribution of the accelerometric data introducing nonlinearities in the distribution of energy. The possible quadratic origin of these mechanic nonlinearities is studied using the corresponding bispectrum and bicoherence of the accelerometric signals.
Keywords: accelerometric analyses; microgravity; spectrum; higher order spectra; bispectrum; bicoherence; nonlinear mechanical systems; international space station; vibration impact.
International Journal of Space Science and Engineering, 2015 Vol.3 No.1, pp.1 - 15
Available online: 12 May 2015 *Full-text access for editors Access for subscribers Purchase this article Comment on this article