Measurement of Vibration Resulting from Non-contact Ultrasound Radiation Force
Measurement of Vibration Resulting from Non-contact Ultrasound Radiation Force
复制标题
非接触式超声波辐射力引起的振动测量
DOI：
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发表时间：
2015
期刊：
影响因子：
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通讯作者：
W. J. Doebler
中科院分区：
文献类型：
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作者：
T. M. Huber;Spencer Batalden;W. J. Doebler
在模态试验中，最常用的激励方法是换能器与被测物体进行机械接触。虽然这种方法是有效的，但有一些微妙的结构需要在没有物理接触的情况下激发振动。超声波辐射力提供了一种非接触激励方法，这种方法是由物体上的声波散射的非线性相互作用产生的。入射超声由频率为f1和f2的正弦波组成；所得到的辐射力在差频f1−f2处有一个分量。通过将差频辐射力与扫描振动计相结合，先前的研究已经证明了从微悬臂到古典吉他等结构的谐振频率和工作挠度形状的完全非接触测量。在目前的研究中，利用聚焦超声换能器的辐射力激发了一个19.6 × 8.1 × 0.37 mm的无夹紧黄铜悬臂梁，其共振频率为610 Hz。通过将传感器安装在计算机控制的平移台上，可以测量传感器的边缘扩展功能；测量这种分布是对施加的辐射力进行量化的重要的第一步。
In modal testing, the most common excitation method is a transducer in mechanical contact with the object under test. While this method is effective, there are delicate structures where it is desirable to excite vibrations without physical contact. The ultrasound radiation force provides a noncontact excitation method resulting from the nonlinear interaction of sound waves scattering from an object. The incident ultrasound consists of sine waves with frequencies of f 1 and f 2; the resulting radiation force has a component at the difference frequency f 1−f 2. By combining the difference frequency radiation force with a scanning vibrometer, previous studies have demonstrated completely non-contact measurements of resonance frequencies and operating deflection shapes of structures ranging from microcantilevers to classical guitars. In the current study, a 19.6 by 8.1 by 0.37 mm clamped-free brass cantilever, with a resonance frequency of 610 Hz, was excited using the radiation force from a focused ultrasound transducer. By mounting the transducer on a computer-controlled translation stage, it enabled measurements of the edge-spread function for the transducer; measuring this distribution is an important first step towards quantifying the applied radiation force.