07-20-2017, 02:06 PM
It's a very interesting trigonometry phenomenon. Our eyes only really engage with a certain angular width before we go from the active area, to a semi-awareness area, to peripheral vision, to nothingness. When you're driving, everything is "coming at you" at your driving speed, but your perception of it is very different depending on your proximity to those objects. If an object is 100m away from you and it gets 10m closer to you in 1s, it doesn't really seem like it's moving that fast since it's only shrunk the distance to you by 10% (going from 100m away to 90m away). Meanwhile, if an object is 11m from you and gets 10m closer to you in 1s, it feels like it's moving really fast since it's shrunk the distance between you by 91% (going from 11m away to 1m away; I don't want it to hit you 
). For reference, 10m/s is 36km/h
If you draw a V-shape on a piece of paper and then two lines on either side of it, say 1cm from the bottom tip of the V and from each other (like so: | | V | |), you can see this effect. Extend the V until it intersects all four lines, each half of the V intersecting two lines. Note how the first line is intersected much closer to the tip of the V and the second line is intersected much farther from the tip of the V. Now imagine you are the tip of the V, the V itself is your active vision area (which is indeed an angular cone extending out from whatever you're focusing on), and the close lines represent a street line Queen, whereas the far lines represent a street like University Ave (especially near RIM Park).
The wider the street, the sooner objects "fall out of" your V, out of your area of active focus. In the wide street, it might fall out of your active view area when it's only reducing the distance between it and you by 10% in that instant. In the narrower street, because the object is so much closer to you before it falls out of your visual focus, it's potentially reducing the distance between it and you by much more than 10% in that instant, and so it feels much faster. (Technical note: this perception effect is primarily due to angular velocity. When a car is coming at you in the other lane and it is far away, it might only take up a few degrees of your vision span, and the degrees it occupies [let's say 0 being straight ahead] might change from 1 through 3 to degrees 5 through 10 very slowly [and they do expand]. When it gets close, it will wind up going from being centered on degree 30 to being centered on degree 45 very quickly, and shoots fastest through degree 90. Yes, I'm getting a bit confused myself, hence calling it a technical note)
So what would be interesting to do would be to find out how fast most drivers felt comfortable driving, how wide their view arc was, and make it such that objects felt like they were going at that fastest-comfortable speed right as they were falling out of the active visual area for drivers driving at the posted speed limit, by putting those street-side objects at the appropriate distance from the driving lane.
Another note would be that the lower a driver sits in their seat, the slower they will think they are going. The same angular V effect happens, because the dashboard rises into their field of view, and makes the roadway disappear farther in front of the car, making it seem like they are going slower than they are. So for short folks who do not adjust their seats to an appropriate height (certainly if I can't see your mouth over the steering wheel, you're far too low in your car), or for folks who intentionally like to sit low-slung in their seats, they are setting themselves up to drive faster and to feel more comfortable doing so.
). For reference, 10m/s is 36km/hIf you draw a V-shape on a piece of paper and then two lines on either side of it, say 1cm from the bottom tip of the V and from each other (like so: | | V | |), you can see this effect. Extend the V until it intersects all four lines, each half of the V intersecting two lines. Note how the first line is intersected much closer to the tip of the V and the second line is intersected much farther from the tip of the V. Now imagine you are the tip of the V, the V itself is your active vision area (which is indeed an angular cone extending out from whatever you're focusing on), and the close lines represent a street line Queen, whereas the far lines represent a street like University Ave (especially near RIM Park).
The wider the street, the sooner objects "fall out of" your V, out of your area of active focus. In the wide street, it might fall out of your active view area when it's only reducing the distance between it and you by 10% in that instant. In the narrower street, because the object is so much closer to you before it falls out of your visual focus, it's potentially reducing the distance between it and you by much more than 10% in that instant, and so it feels much faster. (Technical note: this perception effect is primarily due to angular velocity. When a car is coming at you in the other lane and it is far away, it might only take up a few degrees of your vision span, and the degrees it occupies [let's say 0 being straight ahead] might change from 1 through 3 to degrees 5 through 10 very slowly [and they do expand]. When it gets close, it will wind up going from being centered on degree 30 to being centered on degree 45 very quickly, and shoots fastest through degree 90. Yes, I'm getting a bit confused myself, hence calling it a technical note)
So what would be interesting to do would be to find out how fast most drivers felt comfortable driving, how wide their view arc was, and make it such that objects felt like they were going at that fastest-comfortable speed right as they were falling out of the active visual area for drivers driving at the posted speed limit, by putting those street-side objects at the appropriate distance from the driving lane.
Another note would be that the lower a driver sits in their seat, the slower they will think they are going. The same angular V effect happens, because the dashboard rises into their field of view, and makes the roadway disappear farther in front of the car, making it seem like they are going slower than they are. So for short folks who do not adjust their seats to an appropriate height (certainly if I can't see your mouth over the steering wheel, you're far too low in your car), or for folks who intentionally like to sit low-slung in their seats, they are setting themselves up to drive faster and to feel more comfortable doing so.