1. Head Restraint for Race Car Drivers Aim Jirut and Asif Lala Advised by: Dr. Jackson Roberts

2. Background Fatal neurological damage to the brain ensues after many high speed frontal race car collisions. 13 out of 202-- 1998 Race Car Major Deceleration Crashes were Front Impact Collisions.

3. Background (cont.) For everyday drivers, peak decelerations averaged from 40Gs to 60Gs. For race cars, this peak deceleration maxed at 160 Gs At Peak Decelerations of greater than 40 Gs, concussions are likely to ensue.

4. Project Definition Design, test, and build a prototype for a head restraint system for race cars during racing conditions.

5. Objectives Provide an Easy Escape Mechanism Allow for Sufficient Lateral Visual Range of Motion Provide Sufficient Protection at Maximum Speeds. Be Constructed of Lightweight Materials Be Compatible at Amateur and Professional Race Car Seat Dimensions

6. Possible Solution Models Current restraint systems are insufficient for preventing such injuries. – Air bags – 5-Point Harnesses – Helmets Possible Model Solutions – Crushable Steering Column – Reverse Shock Absorbing Helmet – Bungee Cord – Shock Absorbing Lanyard*

7. Biomechanics of the Problem Parameters (Max) Weight of Head: 8.2% Body Weight = 13lbs or 5.9 kg Weight of Helmet: 3 lbs or 1.4 kg Maximum Speed of Race Car: 230mph or 103 m/s Time of Duration of Impact: 0.067s

8. Biomechanics (cont.) F=ma (Force of Impact on Car) F= (1.4 + 5.9)kg * (103m/s) 0.067s F = 7.3 kg * 1537 m/s2 <= 157 Gs F = 11,220 N or 2,522 lbf

9. Biomechanics (cont.) Parameters (Max) Range of Movement of Torso: 50 degrees (due to 5 point harness) Range of Movement of Neck: 60 degrees Force of Impact of Car: 11,220 N or 2,522 lbf

10. Biomechanics (cont.) Fy=F*cos  y (Force of Torso) F= 11,220 cos (50) = 7,212 N Fy=F*cos  y (Force of Head) F= 7,212 cos (60) = 3,606 N Total force on brain = 7,212 N + 3,606 N = 10,818 N

11. Importance F = 10,818 N From Nahum and Smith

12. Project Idea Shock Absorbing Lanyard Attached from Helmet to Roll Bar From http://www.elkriver.com/zorber.htm

13. Role of the Lanyard Parameters using Lanyard (shock pack) Force Needed to Initiate Tearing = 475 lbf (x2) = 4225 N Weight of Head: 8.2% Body Weight = 13lbs or 5.9 kg Weight of Helmet: 3 lbs or 1.4 kg Maximum Speed of Race Car: 230mph or 103 m/s Time of Duration of Impact: 0.067s

14. Force Calculation F=ma 4225 N = (1.4 + 5.9)kg * a a = 579 m/s2 Therefore, v = 579 m/s2 * 0.067 s v= 39 m/s = 87 mph

15. Current Status Awaiting Force Curves for Each Lanyard in order to compute amount of force decrease. Find an Easy Escape Mechanism Calculate proper locations for lanyard attachments.

16. Future Work (thru April) Order and Build Prototype