Spectrum construction for non stationary vibration: Application to a moving flexible robot
1 École de technologie supérieure, 1100 rue Notre-Dame Ouest, Montréal, Québec, H3C 1K3, Canada
2 Institut de recherche d'Hydro-Québec, 1800 Boul. Lionel-Boulet, Varennes, Québec, J3X 1S1, Canada
a Corresponding author: firstname.lastname@example.org
This paper presents a method for constructing spectrum in non-stationary vibration using time series vector autoregressive model. A modal classification criterion and a modal amplification factor are introduced based on the eigen-decomposition of the block data matrix. The classical spectrum computation can be therefore modified to amplify only the physical modes and lighten the computation induced modes. In combination with a sliding window technique, it is shown that the method provides a clear, lightweight spectral representation of non stationary vibration. Application on the vibration signals measured from a moving flexible robot along a given trajectory shows the effectiveness and applicability of the method. The technique is integrated in the online modal surveillance software call STAR (Short Time AutoRegressive).
© Owned by the authors, published by EDP Sciences, 2015
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