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Shoulder Deflection

Overview​

Shoulder deflection refers to the lateral displacement of the shoulder during a crash, measured along the y-axis [1]. In side impact scenarios, this metric serves as an indicator of upper torso movement in response to structures and restraint systems, such as the door, seat belts, and airbags [2] [3]. If the ATD used in testing has an established Injury Assessment Reference Value (IARV), the maximum shoulder lateral deflection is reported as a percentage of that IARV to indicate potential injury severity [3].

Lateral Shoulder
Lateral Deflection axis at the Shoulder

Required Signals​

  • Shoulder Displacement (Y)

Calculation​

  1. Converts the displacement signal to millimeters (mm)
  2. Filters the displacement signal (CFC = 600)
  3. Calculates the peak displacement and the corresponding time
  4. Calculates the percentage of the IARV threshold reached by the maximum displacement value

References​

[1] Lebarbé, Matthieu & Potier, Pascal & Uriot, Jérôme & Baudrit, Pascal & Lafont, Denis & Douard, Richard. (2018). "Human Shoulder Response to Lateral Impact in Intermediate Loading Conditions Between High-Velocity, Short-Duration and Low-Velocity, Long-Duration. Stapp car crash journal". 62. 319-357.

[2] "U.S. Department of Transportation, National Highway Traffic Safety Administration". (2014). Federal motor vehicle safety standards; child restraint systems, child restraint systems—side impact protection, incorporation by reference. 49 CFR Part 571, Docket No. NHTSA-2014-0012, RIN 2127-AK95.

[3] "Frontal Offset Crashworthiness Evaluation - Guidelines for Rating Injury Measures". No. 2009-06. Insurance Institute for Highway Safety (IIHS), 2009.

[4] "Side Impact Crashworthiness Evaluation - Guidelines for Rating Injury Measures (version III)". Insurance Institute for Highway Safety, May 2014.