通过PVDF阵列设计阶梯梁体积位移传感器

Design of Volume Displacement Sensor for Stepped Beam by PVDF Array

以阶梯梁为例,通过一组阵列式压电薄膜(Polyvinylidene fluoride,PVDF)设计非均匀振动梁的体积位移传感器。在梁表面均匀布置一组相同形状的矩形PVDF阵列,通过测量PVDF与激励力之间的频率响应函数,然后利用伪逆方法结合Tikhonov正则化方法设计这组PVDF阵列的加权系数,从而得到阶梯梁体积位移。实验结果表明,该方法能够准确测量到阶梯梁的体积位移,具有不需计算结构模态、对边界条件有良好的鲁棒性等优点。

With an example of clamped stepped beam,the volume displacement sensor for non-uniform beam was designed by PVDF array. An array of rectangular segment of PVDF film with the same shape equally attached on the surface of the beam were taken as sensors. The frequency response functions between the excitation force and the PVDF film were measured. The output signals of PVDF array were multiplied by appropriate weights designed by the pseudo-inverse method combined with Tikhonov regularization method to gain the volume displacement of the experimental beam. Experimental results show that the volume displacement sensor designed by the proposed method can accurately sense volume displacement. The advantages of the proposed method are that it does not need the structural mode information and has good properties of robustness of the boundary condition.