Measurement of structural intensity on beam structure using angular rate sensor

Abstract

Measuring or calculating structural intensity affords us to understand the propagation paths of vibration and the amount of the transmitted power. In this paper, a new structural intensity measurement method is proposed, in which an angular rate sensor and an accelerometer are used. The results measured by the new method are compared numerically and experimentally with those by the 2-point method with two accelerometers. The 2-point method has the error due to the finite difference to calculate angular displacement from displacements at two points. On the other hand, the new method using the angular rate sensor does not have such error. It is demonstrated that the new method can measure the structural intensity in a beam structure as same as the 2-point method equivalently and more accurately through numerical simulation. Robustness against sensor noise / error is examined; the simulation result has shown that proposed method and 2-point method are both robust enough against regular sensor noise. Further, structural intensity measurement experiments of a simple supported acrylic beam are performed, and the results show that both method could measure structural intensity with similar accuracy.