Sanada Akira, Higashiyama Kouji, Tanaka Nobuo
Industrial Technology Center of Okayama Prefecture, 5301 Haga, Kita-ku, Okayama-shi, Okayama 701-1296, Japan.
Kurashiki Kako Company, Limited, 4630 Yagara, Tsurajima-cho, Kurashiki-shi, Okayama 712-8555, Japan.
J Acoust Soc Am. 2015 Jan;137(1):458-69. doi: 10.1121/1.4904506.
This study deals with the active control of sound transmission through a rectangular panel, based on single input, single output feedforward vibration control using point-force actuators and piezoelectric film sensors. It focuses on the phenomenon in which the sound power transmitted through a finite-sized panel drops significantly at some frequencies just below the resonance frequencies of the panel in the low-frequency range as a result of modal coupling cancellation. In a previous study, it was shown that when point-force actuators are located on nodal lines for the frequency at which this phenomenon occurs, a force equivalent to the incident sound wave can act on the panel. In this study, a practical method for sensing volume velocity using a small number of piezoelectric film strips is investigated. It is found that two quadratically shaped piezoelectric film strips, attached at the same nodal lines as those where the actuators were placed, can sense the volume velocity approximately in the low-frequency range. Results of simulations show that combining the proposed actuation method and the sensing method can achieve a practical control effect at low frequencies over a wide frequency range. Finally, experiments are carried out to demonstrate the validity and feasibility of the proposed method.
本研究基于使用点力致动器和压电薄膜传感器的单输入单输出前馈振动控制，探讨了通过矩形面板进行声音传输的主动控制。研究重点关注在低频范围内，由于模态耦合抵消，通过有限尺寸面板传输的声功率在某些频率下，恰好在面板共振频率之下会显著下降的现象。在先前的一项研究中表明，当点力致动器位于出现该现象的频率的节点线上时，一个与入射声波等效的力可以作用在面板上。在本研究中，研究了一种使用少量压电薄膜条来感测体积速度的实用方法。结果发现，将两个方形压电薄膜条附着在与放置致动器相同的节点线上，在低频范围内可以近似感测体积速度。模拟结果表明，将所提出的致动方法和感测方法相结合，能够在较宽的频率范围内，在低频时实现实用的控制效果。最后，进行了实验以证明所提方法的有效性和可行性。
