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Updated: Aug 23, 2025
07:30
A Test Bed to Examine Helmet Fit and Retention and Biomechanical Measures of Head and Neck Injury in Simulated Impact
Published on: September 21, 2017
9.0K
In Situ Strain Measurements Within Helmet Padding During Linear Impact Testing
Sheng Xu1, MacKenzie Brannen1, Simon Ouellet2
1Department of Mechanical and Aerospace Engineering, Carleton University, 1125 Colonel By Drive, Ottawa, ON, K1S 5B6, Canada.
Annals of Biomedical Engineering
|October 31, 2022
Summary
New in situ X-ray imaging precisely measures helmet deformation during impacts. This advanced technique reveals detailed liner performance, improving helmet design and finite element model validation for better safety.
Area of Science:
- Biomechanics
- Materials Science
- Sports Engineering
Background:
- Traditional helmet impact testing relies on indirect kinematic measurements.
- Interpreting liner response from kinematic data can be challenging for designers.
- Existing methods lack detailed, time-resolved component-level deformation data.
Purpose of the Study:
- Introduce a novel in situ experimental technique for time-resolved helmet deformation measurement.
- Provide detailed component-level insights into helmet performance during impact.
- Enable direct validation and calibration of finite element helmet models.
Main Methods:
- Utilized a high-speed X-ray imaging system for in situ deformation measurement.
- Tested a commercial hockey helmet under linear impacts (2.4–4.5 m/s) with varied impactor caps.
- Monitored foam liner deformation in midsagittal and parasagittal planes.
Main Results:
- Demonstrated a clear dependence of maximum foam strain on impact type, impactor shape, and strain rate.
- Collected comprehensive deformation data at the component level.
- Acquired traditional kinematic metrics alongside detailed deformation data.
Conclusions:
- The in situ X-ray technique offers unprecedented insight into helmet deformation dynamics.
- Results highlight the influence of impact parameters on foam liner strain.
- This method provides a valuable tool for enhancing helmet design and validating computational models.
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