Current Impact Testing :
Current Impact Testing National Operation Committee on Standards for Athletic Equipment (NOCSAE)
Drop mass of 5 kg
Impact up to 272 g
Severity Index (SI)
Max rating for football helmet is 1200 (1)
Goals for Design :
Goals for Design Piezoelectric accelerometer
Measure up to 300 g of acceleration.
Capability to measure acceleration on 3-axes
Sensitivity of the accelerometer oriented around maximum Severity Impact rating for helmet
Constrains :
Constrains Sensitivity limiting the range of testable G-force
Viscous damping designed for unpredictable impacting
References :
References (1) http://www.nocsae.org/standards/pdfs/Standards %20%2710/ND001-08m10-Drop%20Impact%20Test %20Method%20.pdf
(2) http://www.sensr.com/pdf/practical-guide-to-accelerometers.pdf
(3) http://en.wikipedia.org/wiki/Accelerometer
(4) http://www.browndailyherald.com/campus-news /football-helmet-sensors-measure-concussions- 1.1672758