Time domain estimation of response and intensity in beams using wave decomposition and reconstruction

A method is described by which instantaneous values of the response, the in ternal forces and the intensity in beams can be estimated as functions of t ime. The individual components of intensity which propagate in each directi on and the components due to shear and moment can also be estimated. The es timates are provided in real time by digitally filtering the outputs of an array of sensors. The digital filters are designed in the frequency domain using a wave decomposition approach and reconstructed in the time domain as FIR filters in this paper. The design and implementation process is descri bed, numerical simulations of measurements in the farfield performed and an experimental implementation presented. The method is relatively insensitiv e to sensor miscalibration and measurement noise compared to other approach es, and yields instantaneous estimates as well as time averages. (C) 2000 A cademic Press.