1963 McHenry Occupant Simulation Pioneering Research

Subjects related to ATB & ATB clones & the reconstruction and simulation of Occupants in vehicles and Pedestrians struck by vehicles
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1963 McHenry Occupant Simulation Pioneering Research

Post by MSI »

We recently came across of copy of the 1963 paper on the groundbreaking research by Raymond R. McHenry & the folks at the Calspan Transportation Department on Automobile Passenger Restraint Systems and then also found the 1966 validation paper on the original 2D Occupant simulation models
We scanned and have posted here: These were innovative cutting edge research projects which demonstrated the brilliant work of Raymond R. McHenry and the folks at Calspan Transportation Department for modeling occupants and later development of vehicle safety and then collision modeling and reconstruction.
2D occ sim.jpg
2D occ sim.jpg (64.52 KiB) Viewed 770 times
The following is an introduction of why they created the occupant simulation model:

  • In 1963 the U.S. Public Health Service and the Automobile Manufacturer’s Association, Inc. funded research at Calspan performed by Raymond R. McHenry to develop a mathematical model of an automobile occupant in a longitudinal collision. The resulting computer program was called the CAL-2D(i, ii, iii). The research was aimed at the development of a response to a Consumer Reports issue and related reports (v,vi) that included the assertion that American belts failed under the Swedish test conditions and "the major points of failure of the belts tested were the webbing…and the floor brackets themselves".
    The CAL-2D model was created "in order to help improve understanding of the complex relationships of force-acceleration-time-position-velocity that occur in the impact and energy-absorbing cycle of automobile passenger restraint systems". The study was performed to provide guidance concerning
    • (1) fundamental differences in the results obtained by static and dynamic testing and
    • (2) the possible need for dynamic acceptance testing of seat belts.
    One of the results of the study was the conclusion that
    • "the use of a very short stopping distance in a cart test of lap belts can produce a distorted comparison of the strength (when belt loads are not measured) and the performance of webbing materials with different load-elongation characteristics.
      A short (3 inch) cart-stopping distance, from 25 mph, produces increases in the magnitudes of both primary and secondary belt loading cycles over those obtained a more "realistic" (17 inch) stopping distance, as encountered in automobile crashes".
For additional information on Ray's research and additional information on the follow-up 3D Occupant simulation model ATB by John Fleck, please see
test sim compar 2d occ.jpg
test sim compar 2d occ.jpg (57.11 KiB) Viewed 769 times
References from BACKGROUND above:
  • i McHenry “Analysis of the Dynamics of Automobile Passenger- Restraint Systems”, 7th Stapp Car Conference Proceedings, SAE, 1966
  • ii McHenry, Naab “Computer Simulation of the Crash Victim – A Validation Study”, SAE paper 660792, SAE 1966
  • iii Cheng, Sens, Weichel, Gunther “An Overview of the Evolution of Computer Assisted Motor Vehicle Accident Reconstruction”, SAE paper 87-1881
  • iv Consumer Reports, October 1961, Articles by Michelson and Tourin
  • v Michelson, Torin, "Consumer Union's Dynamic Tests of Seat Belts", 5th Stapp Automotive Crash and Field Demonstration Conference, September 1961
  • vi Michelson, I., Aldman, B., Tourin, B. and Mitchel, J. "Dynamic Tests of Automobile Passenger Restraining Devices", Presentation to Committee No. 6, Department of Traffic and Operations, Annual Meeting of the Highway Research Board, Washington DC, January 7, 1963
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