Related Experiment Video
Updated: Aug 5, 2026
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
A Novel Video-Based Method to Estimate American Football Helmet Pad Deformation During Impact Testing
Benjamin Marois1, Pauline Leger1, Yvan Petit1
1Department of Mechanical Engineering, Ecole de technologie supérieure, 1100 Notre-Dame Street West, Montréal, Québec, H3C 1K3, Canada.
Annals of Biomedical Engineering
|July 29, 2026
Summary
A new Pad Deformation Index (PDI) quantifies helmet pad compression during impacts. Higher PDI values correlate with better helmet performance, aiding in the design of safer football helmets.
Area of Science:
- Sports Medicine
- Biomechanics
- Materials Science
Background:
- American football poses high risks for mild traumatic brain injuries (mTBI).
- Existing helmet testing protocols focus on head kinematics, not component behavior.
- mTBI can lead to severe long-term neurological issues like CTE and Alzheimer's disease.
Purpose of the Study:
- Introduce the Pad Deformation Index (PDI) as a novel metric for helmet performance evaluation.
- Quantify the compressive deformation of helmet pads during impact.
- Improve helmet design and testing protocols for better mTBI prevention.
Main Methods:
- Conducted standard helmet impact tests at various velocities.
- Performed mechanical tests on isolated helmet pads.
- Utilized high-speed video analysis to reconstruct impact events and derive PDI.
Main Results:
- Higher PDI values correlated with reduced peak linear acceleration (PLA), Head Injury Criterion (HIC), DAMAGE, and HARM scores.
- Delayed pad densification within high-PDI impacts resulted in the lowest performance scores.
- PDI effectively links impact performance metrics to pad deformation characteristics.
Conclusions:
- The Pad Deformation Index (PDI) is a practical tool for assessing helmet performance.
- PDI can guide the development of advanced helmet designs for improved impact absorption.
- Understanding pad deformation is crucial for mitigating mTBI in sports.
