2005 年 17 巻 1+2 号 p. 1-4
The present paper deals with a comparison of two noise control techniques developed separately; active and semi-passive approaches. A closed rigid box with a loudspeaker inside is designed so that sound pressure is transmitted through a smart board which consists in a clamped steel plate with piezo patches. The present active control technique uses the patches as actuators and a microphone as feedback. The semi-passive technique is a brand new control technique which uses a non-linear approach in which the voltage of piezoelectric patches is switched through an inductance for a very brief period of time when it reaches its maximum or minimum. They are compared and discussed in terms of efficiency on sweeping time response and robustness in non-linear regime. The results revealed that both techniques have different advantages and disadvantages.
