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Updated: Jun 28, 2026
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Investigating the Potential of Singly Curved Thin Piezoelectric Transducers for Energy Harvesting and Structural Health Monitoring
Published on: November 14, 2025
Sound shielding by a piezoelectric membrane and a negative capacitor with feedback control
Tomás Sluka1, Hidekazu Kodama, Eiichi Fukada
1Inst. of Mechatron. & Comput. Eng., Tech. Univ. of Liberec, Liberec.
Summary
This study introduces an adaptive sound-shielding system using piezoelectric materials and a negative capacitor. The system achieves significant, sustained sound transmission loss through self-adjustment, enhancing noise control performance.
Area of Science:
- Acoustics and Materials Science
- Piezoelectric Materials
- Adaptive Systems
Background:
- Traditional sound-shielding methods often lack adaptability to changing environmental conditions.
- Controlling the effective elastic stiffness of piezoelectric materials offers a novel approach to active sound control.
- Existing systems may suffer performance degradation under dynamic operational conditions.
Purpose of the Study:
- To design and realize an adaptive sound-shielding system utilizing piezoelectric materials.
- To investigate the sound-shielding performance and stability of the system under varying conditions.
- To implement a self-adjustment mechanism for long-term, effective sound attenuation.
Main Methods:
- A piezoelectric curved membrane connected to a negative capacitor circuit was employed for sound reflection.
- Acoustic transmission loss was measured at 1.6 kHz with an incident sound pressure level of 80 dB.
- A digital control circuit was integrated to enable self-adjustment of the system's performance.
Main Results:
- The system demonstrated an initial reduction in transmitted sound pressure level from 60 dB to 15 dB.
- Without adaptive control, sound transmission loss degraded by 35 dB within 30 minutes due to changing conditions.
- The integrated digital control circuit successfully eliminated performance deterioration, maintaining a 60 dB acoustic transmission loss.
Conclusions:
- The adaptive sound-shielding system effectively controls sound transmission loss through active stiffness modulation of piezoelectric materials.
- Self-adjustment is crucial for maintaining high sound-shielding performance under dynamic operational conditions.
- The developed system offers a robust and sustainable solution for advanced noise control applications.
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