Experimental identification of the bending equation of beams from the vibration shape measurements

This paper presents an inverse method which results in experimentally determining the parameters of the equation of motion of the linear structures like beams or strings. The experimental part is based on the steady-state measurement of a vibrational shape by a scanning laser vibrometer. An inverse technique is proposed. It compares an experimentally obtained shape with an adequate general solution of the equation of motion and minimizes the error between the two by changing the parameters of the equation. This technique is experimentally verified on three beam samples: a steel beam, a glass composite sandwich beam and a QuietSteel ® sandwich beam.