梁的边界条件的波散射识别方法

new method to identify the boundary parameters of a beam is presented and validated by experiments. The proposed method is based on the wave scattering approach and experimental data. Neglecting transverse shear and rotary inertia, harmonic wave solutions are found using the Euler-Bernoulli beam theory. The basic concept of the approach is to extract the wave mode amplitudes of the bending waves. Then with the wave mode amplitudes and the relationship between the wave modes and the dynamic stiffness, the boundary conditions can be determined immediately. In the proposed technique, in order to identify the parameters independently, the dynamic stiffness is separated into real and imaginary parts. By reason of overcoming the problems caused by measurement noise, the wave mode amplitudes are determined for each discrete frequency. Therefore the dynamic stiffness can be estimated for each frequency and the boundary conditions can be extracted using least squares techniques. An experiment is performed to validate the feasibility and efficiency of the proposed technique. The lumped mass at the boundary is successfully identified.