Blueskies wrote:
>
> I see a quote that says the car was going 53 in a 35 speed limit zone - I suppose that timing had nothing to do with it.
> How about this: The kid saw the car coming, assumed (bad thing!) that it was going at the 35 limit, and bolted. If the
> car was going 35 then it would not have gotten there when the kid was there. Going at the illegal 53 mph caused the car
> to arrive at the scene much sooner, thus killing the child.
>
> Sad day...
>
Based on research at the local university using VR to simulate road
crossing... (I was only watching and helping a fellow grad student)..
One might tend to agree...you also have to consider the individual's
attitude to risk...
With the same "time to collision" people were more likely to have an
accident when crossing (half) the road (That's due to the cable for the
VR helmet only allowing about 20 feet of recorded movement) when the
vehicle was close, or further away.. fewer accidents occurred with the
vehicle at a medium distance ... sorry, can't remember the distances
Meaning..
Close... The person Watches the vehicle for a short period, identifies
that it is traveling "slowly" and attempts to cross the road quickly.
Medium. The vehicle is far enough away that they cross at a brisk speed.
Distant. The vehicle is sufficiently far away that they cross at a
"normal" speed...
(Crossing speed reduces the further away the vehicle is when you start
crossing...)
The time to collision was calibrated to the individual crossing speed
(normal and fast... note that in the virtual environment participants
tended to go faster than the recorded fast crossing rate).
Distance refers to how far away the vehicle is when each trial starts.
Note that, as time to collision is constant, the further away the
vehicle, the faster it has to be traveling...
Conclusion..
Road crossing decisions tend to be made on distance and not speed -- we
typically don't watch the vehicle long enough to judge speed based on
looming rate... note that participants did speed up as the vehicle
approached.. but that is because they are getting more information on
potential time to collision. |