1. ATV Rollover, Operator Response,and Determinants of Injury:Implications for CPDsOctober 12, 2012Chris Van Ee, Ph.D., P.E.Daniel Toomey, M.S.E., P.E.Barbara Moroski-Browne

2. ATV Rollover AccidentsWhat are the factors for If and How an injury/fatality occurs? Injury/Fatality Mechanisms Related to ATV contact during roll? Dynamic or static contact? ATV Kinematics and Kinetics Causes of roll, roll orientation, roll path, roll dynamics, potential contact points along the ATV? Rider Kinematics Active/passive response, dismount, successful separation?Field Data: Injury/Fatality Data Only: extent and significance of problem, target population for the intervention strategy (Existing field data: CPSC IDI) Need ATV and operator dynamic rollover data to further design and further evaluate possible engineering solutions for operator protection. 3. Field Data:Video Database of Real World Rollover Accidents:Search Terms: ATV/quad accidents, crash, flip, wreck, roll, rollover Inclusion Criteria: ATV rollover, occupant and ATV kinematics of the rollCoding: systematically categorized into 48 separate fieldsPre-roll: vehicle characteristics, terrain, pre-event activity, loss ofcontrol factorsRoll: roll trajectory, operator response, ATV/operator contact, injuryoutcome, separation or dismount path Analysis of real world accidents using engineering principles. 4. Field Data: Video DatabaseResults: 129 EventsRoll Direction: 47% Side, 44% Rear, 9% ForwardTerrain: 80% of rolls occur on hillsSpeed at the onset of roll: 86% 10 mph, 53% 3 mphInjury Outcome: 79% Uninjured 16% ATV contact injuries 5% Injury unrelated to ATV contactRider Response 63% of riders attempt an active dismount and 72% of those separate without subsequent ATV contact 15% overall injury rate for those who actively attempt to dismount(91% injuries from ATV contact, 9% from non-ATV contact) 32% injury rate for those not attempting to dismount(71% injuries from ATV contact, 29% from non-ATV contact)Warned Against Behaviors: Average of 2.53 per event 5. Example: Rear Roll Left Knee Impact 6. CPD: Rear Roll DynamicsSource: http://www.quadbar.com.au/the-quadbar/video-library.html 7. CPD: Rear Roll DynamicsRear Mounted CPD Raises ATV CG in Rear RollCG FallHeightCG FallHeightFactors: Ground Impact Forces, Location, Contact Geometry 8. Possible CPD Outcomes1. Straight back over CPD : Raised CG impact INJURY2. Flops laterally (falls onto person or falls to the other side)2a. ATV impact into head/trunk ENHANCED INJURY2b. No contact NO INJURY 9. Rear Roll No InjuryCenter Back Active Dismount 10. Example: Rear Roll Dismount obstructed by Quadbar CPD What is the proper operator response with Quadbar? When and/or how should operator separate? 11. Example: Side RollNo Significant Injury 12. CPD: Side Roll DynamicsSource: http://www.quadbar.com.au/the-quadbar/video-library.html 13. Side Roll Still Frame 14. CPDs are designed to alter the ATV roll kinematics.Changes in ATV kinematics may result in differentinjury outcomes for both injured and non-injuredoperators. 15. Example: Forward Pitch Over No InjuryDescending Steep Slope, Forward Pitch Over,Occupant dismounts and actively scrambles forward to avoid ATV rollout contact 16. Quadbar CPD results in direct contactwith a previously uninjured rider. 17. Field Data: Video DatabaseObservations1. Many different factors can determine if an injurious ATV-rider contact occurs Variations in slope and local terrain change both vehicle and rider kinematics Rider passive and or active response ATV orientation and motion at onset and throughout the roll event2. Small and/or large changes in vehicle roll kinematics result in different vehicle orientations, roll paths, or ground impact forces, and contact geometries. Changes in any of these have the potential to change outcomes of both injured and non-injured people.3. Dismount strategies generally result in successful separation from the vehicle and active dismount strategies result in the lowest incidence of injury.4. Vast majority of rollover events occur on hills including local terrain with significant grade. 18. Field Data: AnalysisObservations: Potential unintended consequences of QB style CPD1.Engineering injury intervention must be guided by the if and how injuries occur.2.Potential unintended consequences must be considered before implementingan engineering design change.3.Based on the ATV and operator kinematics analyzed in this study a. QB does not eliminate the potential for high energy ground impact forces. b. The QB has the potential to change ATV rollover dynamics: Rear rolls: Raises CG, Straight back flop or fall to either side Side Rolls: Raises CG, may accentuate handlebar area contacts Forward Rolls: QB could result in direct focal injurious contact to riders who otherwise would have successfully separated and avoided injury c. QB can impede dismount strategies resulting in fewer successful separations(obstruction, loss of balance, entanglement) d. While providing for a small clearance area in proximity of the posterior seat, it mayaccentuate ground contact forces in the the handlebar-foreseat area. e. QB may limit the ATV from resting in the 180 degree roll (inverted) position, but notfrom reaching or rolling through the inverted position. f. QB may increase the lateral orientation rest position. This may increase both thefrequency and severity of pinning occurrences in ATV side rest orientations. Attorney Work Product - Privileged and Confidential 19. Thank You