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Math professor's side mirror that eliminates 'blind spot' receives US patent

phys.org

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Re: Math professor's side mirror that eliminates 'blind spot' receives US patent

#21

Post by einhverfr »

bitrot wrote: post #14
stephengillie wrote: post #2

In the United States, regulations dictate that cars coming off of the assembly line must have a flat mirror on the driver's side. Curved mirrors are allowed for cars' passenger-side mirrors only if they include the phrase "Objects in mirror are closer than they appear." Because of these regulations, Hicks's mirrors will not be installed on new cars sold in the U.S. any time soon. The mirror may be manufactured and so…

What if you have both?

yeah. The ideal approach is a flat mirror with a curved one inset either above or below. That way you beg both.

However it seems to me that there is a bit of basic math at work here. The more you fit into a mirror of the same size, the smaller the objects will appear and the further away they will look. That strikes me as a very basic premise and I don't think you can get away from that so easily.

Re: Math professor's side mirror that eliminates 'blind spot' receives US patent

#22

Post by bitrot »

einhverfr wrote: post #21
bitrot wrote: post #14

Earlier quoted context omitted.

What if you have both?

yeah. The ideal approach is a flat mirror with a curved one inset either above or below. That way you beg both. However it seems to me that there is a bit of basic math at work here. The more you fit into a mirror of the same size, the smaller the objects will appear and the further away they will look. That strikes me as a very basic premise and I don't think you can get away from that so easily.

I was thinking of having stacked mirrors, the way tractor trucks do. But your comment made me think: is there a way to have a flat mirror turn transparent, revealing a curved mirror behind it? You could activate the transparency just by using your turn signal.

Re: Math professor's side mirror that eliminates 'blind spot' receives US patent

#23

Post by einhverfr »

bitrot wrote: post #22
einhverfr wrote: post #21

Earlier quoted context omitted.

yeah. The ideal approach is a flat mirror with a curved one inset either above or below. That way you beg both. However it seems to me that there is a bit of basic math at work here. The more you fit into a mirror of the same size, the smaller the objects will appear and the further away they will look. That strikes me as a very basic premise and I don't think you can get away from that so easily.

I was thinking of having stacked mirrors, the way tractor trucks do. But your comment made me think: is there a way to have a flat mirror turn transparent, revealing a curved mirror behind it? You could activate the transparency just by using your turn signal.

Yeah, stacked is good.

Re: Math professor's side mirror that eliminates 'blind spot' receives US patent

#24

Post by RyanMcGreal »

aresant wrote: post #8
stephengillie wrote: post #2

In the United States, regulations dictate that cars coming off of the assembly line must have a flat mirror on the driver's side. Curved mirrors are allowed for cars' passenger-side mirrors only if they include the phrase "Objects in mirror are closer than they appear." Because of these regulations, Hicks's mirrors will not be installed on new cars sold in the U.S. any time soon. The mirror may be manufactured and so…

I am an easy sell to jump to conclusions about gov't idiocy but this one is so audacious it seems like there must a relevant reason - so why can't I have a curved mirror that is more efficient?

Reserve your judgment on government idiocy until we see how long it takes the government to update its legislation in response to this new invention.

Re: Math professor's side mirror that eliminates 'blind spot' receives US patent

#25

Post by Jacqued »

I already had a side mirror that eliminates blind spot a few years ago on my Peugeot 207 (I live in Europe) although it didn't have such an angle of vision.

Even though it's a neat invention, I still have to vomit every time I read the word "patent". And to say crooks are working hard to bring these to Europe

Re: Math professor's side mirror that eliminates 'blind spot' receives US patent

#26

Post by Confusion »

archangel_one wrote: post #16
aresant wrote: post #8

Earlier quoted context omitted.

I am an easy sell to jump to conclusions about gov't idiocy but this one is so audacious it seems like there must a relevant reason - so why can't I have a curved mirror that is more efficient?

Curved mirrors are more efficient in one sense but tends to lead people to misjudge distances. Presumably the government think that showing a misleading picture may be worse than not showing one at all, which is not complete idiocy. This mirror apparently doesn't really suffer from that problem, but the legislation didn't anticipate it - which isn't really surprising, it's hardly realistic to expect them to foresee t…

Any mirror tends to lead people to misjudge distances and speeds. Mirrors are not things we naturally understand and you have to get used to judging how far behind you something is, while looking in front of you. If you're looking in a mirror and something comes in your direction very fast, you tend to step back... directly into the thing coming at you.

Curved mirrors also take getting used to, but I doubt it has ever been shown that the number of errors people make because of using curved mirrors is larger than the number of errors people make while using regular mirrors.

These kinds of rules get introduced because someone thinks "this makes sense", other people reading it think "this makes sense" and nobody with enough actual knowledge about the subject, who cares enough and has enough lobbying power, goes "now wait a second, this is not right".

Re: Math professor's side mirror that eliminates 'blind spot' receives US patent

#28

Post by nitrogen »

okamiueru wrote: post #9
stephengillie wrote: post #2

In the United States, regulations dictate that cars coming off of the assembly line must have a flat mirror on the driver's side. Curved mirrors are allowed for cars' passenger-side mirrors only if they include the phrase "Objects in mirror are closer than they appear." Because of these regulations, Hicks's mirrors will not be installed on new cars sold in the U.S. any time soon. The mirror may be manufactured and so…

Maybe since it is based on tiny flat mirrors (like a disco ball), that law can somehow be loopholed. If the law was based on wanting to avoid distortions, whether the law applies to these new mirrors should be reconsidered? Surely, _some_ common sense exists in US legislature?

It's not actually flat:

Hicks noted that, in reality, the mirror does not look like a disco ball up close. There are tens of thousands of such calculations to produce a mirror that has a smooth, nonuniform curve.

I imagine "tens of thousands of such calculations" is newspaper code for integration.

If someone assigned me the task of making such a mirror, I would start by treating the mirror like a monitor displaying a 3D scene, and calculate the vectors necessary to project a 45 degree view onto the surface of the mirror (i.e. start with a virtual camera behind the mirror such that it has a 45 degree field of view). I would then adjust those vectors so that the image will look like such a projection when seen by a viewer a few feet up and to the right, with the mirror occupying ~15 degrees of the viewer's FOV.

In other words, everything I need to know I learned from video games.

Re: Math professor's side mirror that eliminates 'blind spot' receives US patent

#29

Post by confluence »

Relevant: http://www.quora.com/Why-haven-t-cars-yet-solved-the-problem...

Apparently most people set up their mirrors incorrectly by overlapping view paths, when it would in fact be better if things moved between mirrors without any overlap (e.g. rear view mirror covers the back whilst the side mirrors cover blind spots - no overlap in between).

I've tried it out and it feels rather weird, but I must say I've found it quite effective. I still do head checks, but mostly just out of habit, and it's a good extra check to use just before you change lanes.

Re: Math professor's side mirror that eliminates 'blind spot' receives US patent

#30

Post by hahainternet »

Confusion wrote: post #26
archangel_one wrote: post #16

Earlier quoted context omitted.

Curved mirrors are more efficient in one sense but tends to lead people to misjudge distances. Presumably the government think that showing a misleading picture may be worse than not showing one at all, which is not complete idiocy. This mirror apparently doesn't really suffer from that problem, but the legislation didn't anticipate it - which isn't really surprising, it's hardly realistic to expect them to foresee t…

Any mirror tends to lead people to misjudge distances and speeds. Mirrors are not things we naturally understand and you have to get used to judging how far behind you something is, while looking in front of you. If you're looking in a mirror and something comes in your direction very fast, you tend to step back... directly into the thing coming at you. Curved mirrors also take getting used to, but I doubt it has eve…

You seem to be doing exactly what you're condemning them for. Just because your opinion differs from theirs is no reason to assume they are incorrect or that there are no studies involved.
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