A wearable hydraulic shock absorber with efficient energy dissipation

Thumbnail Image



Journal Title

Journal ISSN

Volume Title

Repository Usage Stats


Citation Stats

Attention Stats


Advances in shock absorber technology are often translated to wearable personal protective equipment (PPE) to protect humans from impact-related injuries. However, the effectiveness of PPE is limited by factors such as the tolerable size and weight of the PPE device and the environmental conditions in which the PPE will be used. In this study, we leveraged the energy dissipation of fluid flow using soft structures to prototype a novel, wearable hydraulic shock absorber — the Soft Hydraulic Shock. The Soft Hydraulic Shock achieved an efficient energy absorption ratio of 100 % across a range of impact loading conditions due to its fluid-based mechanism of energy absorption. In comparison, five state-of-the-art shock-absorbing technologies with similar dimensions and weights used in American football helmets were found to have average energy absorption ratios ranging from 74.0 % to 90.0 %, on average. Furthermore, the Soft Hydraulic Shock maintained a stable energy dissipation across a wide range of temperatures (-18 °C, 19.5 °C, 50 °C), while the energy dissipation of other shock absorbing technologies varied up to 20 % across these temperatures. Analyses of the behavior of the Soft Hydraulic Shock with different design parameters and impact loadings were further explored with a validated finite element model of the device. Finally, the Soft Hydraulic Shock demonstrated the ability to significantly mitigate brain injury risk (average 23.9 % reduction in Head Acceleration Response Metric) when implemented into a full helmet system. The results of this study demonstrate the promise of wearable hydraulic shock absorbers and provide a platform for further optimizing their performance.






Published Version (Please cite this version)


Publication Info

Cecchi, NJ, Y Liu, RV Vegesna, X Zhan, W Yang, LA Espinoza Campomanes, GA Grant, DB Camarillo, et al. (2024). A wearable hydraulic shock absorber with efficient energy dissipation. International Journal of Mechanical Sciences, 270. pp. 109097–109097. 10.1016/j.ijmecsci.2024.109097 Retrieved from https://hdl.handle.net/10161/30404.

This is constructed from limited available data and may be imprecise. To cite this article, please review & use the official citation provided by the journal.



Gerald Arthur Grant

Allan H. Friedman Distinguished Professor of Neurosurgery

Unless otherwise indicated, scholarly articles published by Duke faculty members are made available here with a CC-BY-NC (Creative Commons Attribution Non-Commercial) license, as enabled by the Duke Open Access Policy. If you wish to use the materials in ways not already permitted under CC-BY-NC, please consult the copyright owner. Other materials are made available here through the author’s grant of a non-exclusive license to make their work openly accessible.