Energy Harvesting from a Non-linear Standing Beam-Mass System: Two- versus One-Mode Approximations

SAM Lajimi (University of Waterloo, Canada) & MI Friswell (Swansea University)

Journal of Intelligent Material Systems and Structures, Vol. 28, No. 8, May 2017, pp. 1010-1022


We investigate the effect of including the second mode of natural vibration on the computed response of a forced nonlinear gravity-loaded beam-mass structure used for non-linear piezoelectric energy harvesting. By using the method of assumed-modes and Lagrange equations, we develop the discretized equations of generalized coordinates of the system including the electro-mechanical equation. The equation of motion is further simplified to find the single-mode approximation. The phase-portraits, time-histories, PoincarĀ„'e sections, and frequency-response curves of the system are computed. It is shown that the number of mode-shapes affects the response and it is required to include higher modes to improve the analytical-computational results. The system shows distinct behavior varying from a linear single-frequency response to a multi-frequency chaotic response. The average power across the load resistor consequently shows a noticeable variation depending on the characteristics of the overall system response.

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This material has been published in the Journal of Intelligent Material Systems and Structures, Vol. 28, No. 8, May 2017, pp. 1010-1022, the only definitive repository of the content that has been certified and accepted after peer review. Copyright and all rights therein are retained by the Sage.

Link to paper using doi: 10.1177/1045389X16667852

Journal of Intelligent Material Systems and Structures