A Review of Morphology Characteristics and Sensing Mechanisms of Harbor Seal Whiskers

ZHAO Hanghao; JI Chunning; LI Xianghe; ZHANG Zhimeng; YUAN Dekui; ZHANG Jinfeng; CHEN Weilin

doi:10.6052/1000-0992-25-037

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Article Navigation > Advances in Mechanics > 2026 > Accepted Manuscript

Zhao H H, Ji C N, Li X H, Zhang Z M, Yuan D K, Zhang J F, Chen W L. A Review of Morphology Characteristics and Sensing Mechanisms of Harbor Seal Whiskers. Advances in Mechanics, in press doi: 10.6052/1000-0992-25-037

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Zhao H H, Ji C N, Li X H, Zhang Z M, Yuan D K, Zhang J F, Chen W L. A Review of Morphology Characteristics and Sensing Mechanisms of Harbor Seal Whiskers. Advances in Mechanics, in press doi: 10.6052/1000-0992-25-037

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A Review of Morphology Characteristics and Sensing Mechanisms of Harbor Seal Whiskers

doi: 10.6052/1000-0992-25-037 cstr: 32046.14.1000-0992-25-037

State Key Laboratory of Hydraulic Engineering Intelligent Construction and Operation, Tianjin University, Tianjin 300350, China

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Corresponding author: cnji@tju.edu.cn
Received Date: 2025-11-29
Accepted Date: 2026-02-25

Available Online: 2026-03-05

Abstract

Abstract

With their uniquely three-dimensional, wavy whiskers, Harbor seals (Phoca vitulina) exhibit exceptional underwater sensing capabilities. Studies have shown that Harbor seals can detect weak vortices with flow velocities as low as 245 μm/s and can track hydrodynamic trails left by targets up to 180 meters away and as long as 35 seconds earlier. These abilities highlight the remarkable advantages of Harbor seal whiskers in underwater vortex sensing and hydrodynamic trail tracking. Bio-inspired sensor designs based on Harbor seal whiskers have thus become a research hotspot in biomimetic science and engineering, demonstrating promising applications in underwater target detection and recognition. This paper first reviews research progress on the morphological characteristics and geometric modeling of harbor seal whiskers, summarizing and comparing the strengths and limitations of different simplified models. It then provides an overview of advances in the hydrodynamic characteristics of biomimetic whisker models, covering wake features and vibration responses of such models in uniform and wake flows, the sensing mechanisms of harbor seal whiskers, interactions within whisker arrays, and applications of artificial intelligence methods in sensing-signal recognition. Finally, based on the shortcomings and key open questions in existing research, the paper outlines several research directions that warrant attention for advancing biomimetic science and engineering applications of harbor seal whiskers.
- Harbor Seal Whiskers,
- Geometric Morphology,
- Hydrodynamic Characteristics,
- Vortex Sensing,
- Biomimetic

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References(70)

References

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