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Underwater acoustic spiral wavefront transducer with low phase directionality error
Rongzhen Guo1,2,3, Wei Lu1,2,3, Yu Lan1,2,3
1National Key Laboratory of Underwater Acoustic Technology, Harbin Engineering University, Harbin 150001, China.
The Journal of the Acoustical Society of America
|November 20, 2024
Summary
This study introduces a novel spiral wavefront transducer designed to enhance underwater vehicle positioning accuracy. The transducer minimizes phase directionality error in acoustic waves, leading to more precise azimuth determination.
Area of Science:
- Acoustics
- Robotics
- Signal Processing
Background:
- Azimuth determination for unmanned underwater vehicles (UUVs) relies on acoustic spiral wavefronts.
- Phase directionality error in transducers limits UUV positioning accuracy.
Purpose of the Study:
- To develop a spiral wavefront transducer that reduces phase directionality error.
- To improve the underwater positioning accuracy of UUVs.
Main Methods:
- Investigated the linear relationship between phase and azimuth angle of acoustic spiral wavefronts.
- Analyzed causes of phase directionality error in phased-spiral transducers.
- Proposed optimization design principles for minimizing error.
- Designed, fabricated, and tested a transducer prototype.
Main Results:
- The prototype emits low-frequency acoustic spiral wavefronts with low phase directionality error (1.45°).
- Experimental results for transmitting voltage response and phase directionality agreed with simulations.
- Achieved a resonance frequency of 1312 Hz and a maximum transmitting voltage response of 129.7 dB.
Conclusions:
- The proposed spiral wavefront transducer effectively minimizes phase directionality error.
- This leads to enhanced accuracy in UUV underwater positioning.
- The design principles offer a pathway for future transducer optimization.
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