Olson v Baker Driver Perception/Response Times

[MSI]

Q: I would like to gather opinions on the merits or applicability in casework of perception-reaction time as defined by Paul Olson in "Forensic aspects of driver perception and response" (2010) versus that by J Stan Baker in "Perception and reaction in traffic crashes". I was told that Baker's definition had an advantage in reducing ambiguity regarding which point a hazard can be considered perceptible to a driver. However I am skeptical as definitions of PRT include similar components (however named or categorized) which need to be accounted for. When PRT starts is often quite a challenge.

A: Since we've been buried in preparing and releasing our msmac3D software we've been somewhat out of the loop on the most recent developments in driver preception/reaction studies. Particularly now with many studies which incorporate built in video systems so actual crashes (as opposed to laboratory or staged settings) are being investigated.
For example, SAE 2005-01-0426 Factors that Influence Drivers' Response Choice Decisions in Video Recorded Crashes.
We recommend you contact Jeffrey Muttart and/or Crash Safety Research and/or Crash Safety Solutions.
They specialize in driver perception/response and all things driver related and so might point you to papers which may include reviews and comparisons of Olson vs Baker.
I will also drop Jeff an email and post up any response i get from him on your question.

[MSI]

I received the following response from Jeffrey Muttart, Crash Safety Research Center, LLC.
Thank you Jeff!

• As the person responsible for all Human Factors curriculum at NU-CPS, we recognize that the "Fricke" book must be updated. Anyone still using a Baker book is using outdated information.
  I will be rewriting the human factors chapter. Dr. Olson is a respected colleague but you cannot take his results verbatim (he would agree). As Daubert tells us...
  • We must use accepted research or methods...
    And we must apply it properly.
  Olson and Sivak measured brake response to a yellow piece of foam 150 ft. Ahead after cresting the knoll of a hill.
  • Do you get skid marks when you touch a brake? If not, then add 0.25 to 0.3 sec (Muttart 2003 Muttart, 2004, chapter 14), Ising et all, 2012)
  • What if it's in a highway - add 0.6 seconds (Muttart, 2005).
  • What if at night? - add 0.22 sec (Muttart, 2003- SAE)
  • What if the hazard is not directly ahead like the foam was? - add 0.3 sec for every 10 degrees - the roadside is near 10 degrees many times.
  In general, there are a few common PRTs
  • • (including braking -steering wheel time but not maneuver time)-
      see Muttart, 2004 (handbook for human factors in litigation chapter 14)
  • Day- straight road - 1.8 sec +\- 0.7 sec
  • Day- non-straight (intersection, curve, crossing guard, etc) 1.3 sec +\- 0.5 sec
  • Night- straight - 2.1 +\- 0.8 sec
  • Night - non straight - 1.6 +\- 0.7 sec
  • Two cars following closely behind and front car brakes 1 sec +\- 0.3 sec
  • Two cars, one stopped and the other approaches at high speed- get a human factors expert / this is a longer PRT many times.
  • Being cut off In Traffic 1.0 sec +\- 0.5 sec
  Each of these instances are rules of thumb -
  • a thorough analysis of all objective factors will likely be better than a rule of thumb -
    I encourage people to attend the class at Northwestern.
  I will only ask - how do you know what you don't know? Much of what I teach, no recon knows about, but I think most will agree that the information addresses information for every case.
  
  • Jeffrey W Muttart, Ph.D., ACTAR#96
    Director of Research and Consulting
    Crash Safety Research Center, LLC
    82 Main Street, Suite 3
    East Hampton, CT 06424

Thank you again Jeff!

[MSI]

And let me add a little more information on the type of class Jeffrey W Muttart teaches:

• Advanced Crash Reconstruction Utilizing Human Factors Research
  The class includes Jeff teaching:
  • 1. How acceleration choice changes
    • - lateral
      - forward
      - backing
    2. PRT - as stated
    3. Night recognition
    4. Whether a driver pulls out or not
    • probabilities given the presence of an approaching vehicle at a given distance
    5. Pedestrian walking/running speed at intersections/mid-block
    • in good weather and bad, when violating a signal and when not
    6. Drivers ability to estimate closing speed
  and much more...

See Advanced Crash Reconstruction Utilizing Human Factors Research for additional information