1 Observational Study of Head Restraint Use Protocol Development and Results BC Whiplash Prevention Campaign By: Dr. Douglas P. Romilly, Harry Luk, Peter Xing (UBC Mechanical Engineering), Dr. Marc White (UBC/CIRPD), Dr. Ediriweera Desapriya (UBC/BCIRPU)
2 Why Whiplash? In the US whiplash injuries account for over 2 million insurance claims each year In British Columbia alone, the economic costs exceed C$600 million/year (ICBC) Whiplash injuries account for more than 70% of all bodily injury claims (Navin et al., 2000). Cost is in terms of Lost work productivity Disability Sick leave Litigation Medical care
3 What is the Problem? NL 15% BC 18% AB 16% ON 13% PEI 8% NS 12% NB 7% Proper head restraint positioning statistics across Canada 14% (average)!
4 Whiplash Prevention Campaign Goal GOAL: Increase proper head restraint use by educating the public and promoting use: social marketing strategies vehicle safety awareness programs Our need: a tool to assess proper head restraint use (i.e. required to evaluate the effectiveness of the developed safety programs and strategies related to enhancing proper head restraint use)
5 Proper Head Restraint Adjustment Raise the head restraint (HR) so that the center of the head restraint is slightly above the top of the ear. This usually brings the HR top to near head height and is used as measure by IIHS. The head restraint should be 2-8 centimeters from the back of your head When adjusted properly the head restraint can be very effective in preventing injuries
6 Observational Study - Objectives 1) Develop a method to measure the head-to-head restraint position Procedure: Obtain image of seated occupant Locate suitable points on head and head restraint and find image dimensions (i.e. in pixels) Calibrate image dimensions to real Calculate actual distances between head and head restraint
7 Capture Data - Sample Image
8 Calibration Principle Target - Head & head restraint
9 Equipment Selected Image capture DSLR Camera 1/4000 frames/sec Distance measurement Laser range finder (light sensitivity issue) Ultrasonic distance tool (custom) Validation/accuracy (+/- 0.1 ~ 0.2 cm) Same day and hour image obtained with and without polarizing filter
10 Observational Study - Objectives 2) Use IIHS* standard to assess data wrt whiplash protection Procedures: Compare vertical and horizontal distances to height and backset Vertical Horizontal Poor >10 cm > 12 cm Marginal 8-10 cm cm Acceptable 6-8 cm 8-10 cm Good < 6 cm < 8 cm * Insurance Institute of Highway Safety height references top of HR to top of head.
11 Custom Analysis Software UBC Head Restraint Analyzer Image analysis - curve fitting based on MATLAB image analysis toolkit IIHS assessment using custom software User-friendly!
12 HR Analyzer - Sample Data Output
13 Conclusions 1) Developed an observational study measurement system and protocol utilizing calibrated image analysis provides reliable results (via validation testing) protocols allow for in-field use without distraction to occupants 2) Developed custom software tools to assess HR usage data based on IIHS ratings
14 Conclusions System provides classified deterministic rather than subjective assessment Data trends we can provide: position info (horizontal & vertical) driver vs. passenger trends type of vehicle (sports car, sedan, SUV, etc.) region (urban vs. rural) relative success of safety programs and initiatives!
15 Conclusions: Check your Head Restraint! Proper Head Restraint Adjustment Raise the head restraint (HR) so that the center of the head restraint is slightly above the top of the ear The head restraint should be 2-8 centimeters from the back of your head Acknowledgement: Thanks to the AUTO21 NCE for funding this research work!