Shrinking car side mirrors

Pandamonium

Golden Member
Aug 19, 2001
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What's to stop us from designing a side mirror mechanism that protrudes ~1-2" from the vehicle but provides equal or better visibility? It's been a very long time since I've done any physics problems with mirrors and images, but from what I remember, I can't think of a theoretical reason why we can't do this.

To be honest, I'm interested in this mainly because I figure smaller side mirrors would lead to a reduction in wind noise at highway speeds. A secondary benefit, and probably the selling point for most other people, would be a reduction in drag. I'd imagine that greater gains in fuel economy could be had from engine design and weight reduction, but at some point of diminishing returns, reducing drag might be worthwhile.

My thought is this:
1) A small convex mirror in an aerodynamic but protruding "nub" would serve to reflect light from external objects
2) Inside the vehicle there would be some kind of adjustable lens system to redistribute rays from that mirror onto a flat mirror (to reverse the distortion from the convex mirror).
3) Driver would look on the interior flat mirrors.

My thinking is that while cameras would probably be lighter weight, they add complexity and a point of failure that I doubt government regulations would accept. So we keep the mirrors but move some of the mechanism inside the vehicle. It's not like most of us use the outside edges of our dashboards anyway.

But really, this is all to reduce wind noise at highway speeds.
 

CycloWizard

Lifer
Sep 10, 2001
12,348
1
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Smaller mirrors will result in decreased optical quality. Convex mirrors inherently lose some depth information. The amount of information lost depends on the curvature. Making the mirrors more curved (which is essentially what you're proposing) would make it almost impossible to determine the depth of objects in the mirror. "Objects in mirror are closer than they appear" is a problem even with mirrors that are only slightly convex.
 

Modelworks

Lifer
Feb 22, 2007
16,240
7
76
There was a lab somewhere doing testing on using fiber optics to pipe the image from anywhere and restoring it so it displays on a surface without any need for electronics. The problem, if I remember right, was the cost of the optics was too high. Remember things like cars are all about price points so something that increases the cost to make it by even $1 is a point of contention.
 

Snapshot1

Member
Dec 26, 2011
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Wouldn't the answer to the issues of noise, quality, appearance, etc. be to get rid of mirrors entirely, replacing them with suitable cameras and screen?

It is likely an issue at the moment because of DOT and similar regulations on vehicles but that is something that could be changed once it is demonstrated that a camera / screen system is suitable and reliable.

Cameras could offer adjustable focal length and fields of view, infrared capability, the video could be recorded, and a very small camera housing could produce a very nice image on a screen.

Snapshot1
 

jagec

Lifer
Apr 30, 2004
24,442
6
81
Wouldn't the answer to the issues of noise, quality, appearance, etc. be to get rid of mirrors entirely, replacing them with suitable cameras and screen?

It is likely an issue at the moment because of DOT and similar regulations on vehicles but that is something that could be changed once it is demonstrated that a camera / screen system is suitable and reliable.

Cameras could offer adjustable focal length and fields of view, infrared capability, the video could be recorded, and a very small camera housing could produce a very nice image on a screen.

Snapshot1

Yup. Some hypermilers deliberately remove the passenger-side mirror (remember, some cars didn't have them at all in the 80s), which apparently produces a noticeable gain in fuel mileage.

Cameras may very well be the future. After all, the rearview mirror is more useful than the side mirrors anyway.
 

Aluvus

Platinum Member
Apr 27, 2006
2,913
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Cameras may very well be the future. After all, the rearview mirror is more useful than the side mirrors anyway.

Really? I use the side mirrors for changing lanes, backing up when there are objects to the sides, backing up while turning, etc. I guess if all you ever do is drive around in an empty field with no other cars you don't need them.
 

AD5MB

Member
Nov 1, 2011
81
0
61
After all, the rearview mirror is more useful than the side mirrors anyway.

you must be joking. they put the abominations at eye level so you can't see traffic from the right.

side mirrors let you see to the sides. stupid people pull alongside and hang there. how are you going to see the stupid people if you don't have side mirrors?
 

CycloWizard

Lifer
Sep 10, 2001
12,348
1
81
I forgot to mention that shrinking mirrors will also decrease the spatial resolution of the image. The eye has a very good spatial frequency (IIRC, 500 lines/inch), but condensing the information from a mirror into smaller areas will push back against this limit.
 

Pandamonium

Golden Member
Aug 19, 2001
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So despite some losses in image resolution and depth of field, are there theoretical problems in a passive mirroring system?
 

AD5MB

Member
Nov 1, 2011
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0
61
a problem pilots have:

  • you have your head out of the cockpit ( you are looking out the windows )
  • you move your head inside the cockpit ( you check the gauges, read the chart, et cetera )
  • you force your eyes to focus on what you are looking at
  • you get back outside the cockpit, and your eyes are focused for inside the cockpit, and you don't see big things outside the cockpit until your eyes refocus for distance.
  • your eyes do not refocus until they see something to refocus on. they don't see something to refocus on because they are not focused... which is why you stumble around blindly first thing in the morning.
which is why I have Ford F-150 mirrors on my baja bug. You can find the mirrors, see whats in them, and get your eyes back out the windshield fast

if you put a video monitor in place of mirrors, you have to
  • get your head in the cockpit,
  • find the monitor,
  • refocus for the distance to the monitor,
  • see what's there,
  • and get your head back out of the cockpit and refocus
in traffic

with mirrors, your eyes, which are focused for distance, see the distant reflection. when you look forward again you still have distant focus.

with a monitor you need to refocus for shorter range, then refocus for - well, you will know it when you see it. you will see it when you focus.

how long that takes is the problem
 

CycloWizard

Lifer
Sep 10, 2001
12,348
1
81
So despite some losses in image resolution and depth of field, are there theoretical problems in a passive mirroring system?
Other than not being able to see anything in the mirror due to the two effects I mentioned already, no I don't believe there are any theoretical limitations to such a system. :p
 

jagec

Lifer
Apr 30, 2004
24,442
6
81
Really? I use the side mirrors for changing lanes, backing up when there are objects to the sides, backing up while turning, etc. I guess if all you ever do is drive around in an empty field with no other cars you don't need them.

I use all 3 mirrors, of course, but the rearview mirror is the one with the largest field of view by far. And that's stock--installing one of those funky HUGE rearview mirrors would provide 90% of the utility of the sideview mirrors without any of the accompanying noise or wind resistance.

I'm not going to do it, but I can understand why others might.
 

Snapshot1

Member
Dec 26, 2011
42
0
0
a problem pilots have:

  • you have your head out of the cockpit ( you are looking out the windows )
  • you move your head inside the cockpit ( you check the gauges, read the chart, et cetera )
  • you force your eyes to focus on what you are looking at
  • you get back outside the cockpit, and your eyes are focused for inside the cockpit, and you don't see big things outside the cockpit until your eyes refocus for distance.
  • your eyes do not refocus until they see something to refocus on. they don't see something to refocus on because they are not focused... which is why you stumble around blindly first thing in the morning.
which is why I have Ford F-150 mirrors on my baja bug. You can find the mirrors, see whats in them, and get your eyes back out the windshield fast

if you put a video monitor in place of mirrors, you have to
  • get your head in the cockpit,
  • find the monitor,
  • refocus for the distance to the monitor,
  • see what's there,
  • and get your head back out of the cockpit and refocus
in traffic

with mirrors, your eyes, which are focused for distance, see the distant reflection. when you look forward again you still have distant focus.

with a monitor you need to refocus for shorter range, then refocus for - well, you will know it when you see it. you will see it when you focus.

how long that takes is the problem

True, which is partly why tactical (and some airline and business jets) are using heads-up (and now helmet) displays to help maintain overall situational awareness.

But with traditional mirrors and other in-vehicle displays you already have some aspects of this problem without any of the potential benefits of camera technology.

The effectiveness of a camera / screen system depends on a number of things including reliability, resolution, display placement and certainly driver training and familiarity.

A friend has a recreational motor coach which includes rear-looking cameras in each side mirror and a back-up camera at rear center. Operating the turn signal selects which camera to display - left signal, left camera, right signal, right camera, no signal, rear camera. This is a very effective system, both for low speed maneuvering and for certain aspects of highway driving. It is not eliminate the side mirrors – these are huge on this vehicle, but the actual camera housing is small.

It is a big step to go from side mirrors to cameras + display, but most of what is needed already exists and I think we will eventually see this on many vehicles.

Snapshot1
 

Throckmorton

Lifer
Aug 23, 2007
16,829
3
0
There are people on Ecomodder with internal mirrors. The field of view isn't as good but they get by.

BTW, mirrors account for 5% of total drag on one car that was tested. Huge amount for such little things.
 

Throckmorton

Lifer
Aug 23, 2007
16,829
3
0
Mirror.jpg
 

CycloWizard

Lifer
Sep 10, 2001
12,348
1
81
There are people on Ecomodder with internal mirrors. The field of view isn't as good but they get by.

BTW, mirrors account for 5% of total drag on one car that was tested. Huge amount for such little things.
Your car's drag will be much higher due to a car-sized imprint on the side than just having a mirror out there to prevent the accident in the first place. Young drivers might be able to get away with the shrunken internal mirror, but aged drivers will have a very hard time with it.
 

sm625

Diamond Member
May 6, 2011
8,172
137
106
When I busted off my passenger side mirror (derp) my fuel economy did not improve one nickel.

You have to consider the amount of petroleum it would cost to re-engineer mirrors vs the amount of petroleum saved by doing so. When the government gets involved the costs of changing in terms of petro-dollars rises dramatically. And if there is any increase in accident risk then you have to quantify that too in terms of petro-dollars.
 

xj0hnx

Diamond Member
Dec 18, 2007
9,262
3
76
Small rear facing near where rear view mirrors are now, connected to a small screen inside the car in about the same place as those inside mirrors.
 

GWestphal

Golden Member
Jul 22, 2009
1,120
0
76
They should just have two weather sealed 720p webcams, one on either side of the car. You could make it controllable too. That way you don't get those "brights" reflected in your eyes either.
 

SMOGZINN

Lifer
Jun 17, 2005
14,228
4,469
136
With current technology we could probably get rid of windows altogether and go with a dozen small HD cameras mounted all around the vehicle with their output displayed on an interior OLED dome. I bet it would seriously improve the safety of cars during crash tests to not have large windows directly in front of the passengers.

Then get some decent computing power available to the system and you can have all sorts of enhanced vision elements added. Stuff like target painting of other cars, pedestrians, and road obstructions. Create ad-hoc networks with other cars around you and you could even ‘see’ road conditions far ahead of you, or get another cars perspective for changing lanes or backing up. Throw in some ambient advertising and sell real time date collection and you would probably even lower the cost of cars while doing it.

Personally, I think cameras are coming to cars very soon. Just think of the advantage such a thing would be to insurance companies! It is an idea whose time that is already overdue.
 

mindless1

Diamond Member
Aug 11, 2001
8,541
1,652
126
Don't know about you guys but I have electronics that fail every now and then. There's no way I'd trust cameras over glass and mirrors which tend to work forever unless you've already wrecked. I suppose you could have redundant cameras so failure isn't as much of a problem but I don't see electronics as an answer to vehicle safety, they'll just create the illusion of safety so people drive faster while texting.

Used to be, people did drive slower on average than they do today. We made cars that handle better so people drive faster because they feel safer.

I'm not as confident that all the electronics that add to vehicle cost will be an advantage to insurance companies. Granted the added cost pales in comparison to medical bills from an injury but in my mind it still comes back to perceived risk - the safer someone feels driving fast, the faster they'll drive.
 

CycloWizard

Lifer
Sep 10, 2001
12,348
1
81
Don't know about you guys but I have electronics that fail every now and then. There's no way I'd trust cameras over glass and mirrors which tend to work forever unless you've already wrecked. I suppose you could have redundant cameras so failure isn't as much of a problem but I don't see electronics as an answer to vehicle safety, they'll just create the illusion of safety so people drive faster while texting.

Used to be, people did drive slower on average than they do today. We made cars that handle better so people drive faster because they feel safer.

I'm not as confident that all the electronics that add to vehicle cost will be an advantage to insurance companies. Granted the added cost pales in comparison to medical bills from an injury but in my mind it still comes back to perceived risk - the safer someone feels driving fast, the faster they'll drive.
I can buy a 1080p webcam for less than a glass mirror at this point. These cameras are not really subject to random failure either. You might lose a pixel here or there, but that's not going to influence anything.
 

mindless1

Diamond Member
Aug 11, 2001
8,541
1,652
126
I can buy a 1080p webcam for less than a glass mirror at this point.

It's not the same thing. Even a device VERY simple compared to a webcam like a mass airflow sensor costs quite a lot to test and integrated into an automobile, or replace later. Plus you're not buying "a" webcam, you're buying a vibration and weather resistant subsystem including at least an integrating display. It will easily add a thousand dollars over mirrors because it can't be a one-off hack, it has to withstand the scrutiny of safety agencies, be idiot-proof, and good enough that the lawsuit liabilities don't increase disproportionately... to never fail because being able to see is a critical component of driving.

These cameras are not really subject to random failure either. You might lose a pixel here or there, but that's not going to influence anything.

Do you leave your webcam outside strapped to a vehicle for over a dozen years in rain, snow, cold of winter and heat of summer? We could think all it needs is a weatherproof housing, as if we can ignore that seals on vehicles fail all the time. Do you refocus the cheap webcam thousands of times every day like the human eye may, to focus on objects at different distances?

Can you travel through time to put today's inexpensive webcam on a vehicle in that grueling scenario then check it a dozen years from now? I find it extremely optimistic to think it will be reliable enough to trust your life on it and even if you plan on replacing your vehicle before it's a dozen years old, there's still the other vehicles on the road to contend with.

Essentially I wouldn't call it random failure at all, suspecting that most if not ALL of them would fail from heat, shock stress, or mechanical zoom mechanism faults within the lifespan of the vehicle unless they are very expensive and tested rigorously for years - certainly not today's cheap webcams. I'm not suggesting cameras will never be a good idea, only that we're not there yet and the risk and cost is too high to save a hypothetical 5% on fuel consumption except in niche applications.
 
Last edited:

Howard

Lifer
Oct 14, 1999
47,982
10
81
It's not the same thing. Even a device VERY simple compared to a webcam like a mass airflow sensor costs quite a lot to test and integrated into an automobile, or replace later. Plus you're not buying "a" webcam, you're buying a vibration and weather resistant subsystem including at least an integrating display. It will easily add a thousand dollars over mirrors because it can't be a one-off hack, it has to withstand the scrutiny of safety agencies, be idiot-proof, and good enough that the lawsuit liabilities don't increase disproportionately... to never fail because being able to see is a critical component of driving.



Do you leave your webcam outside strapped to a vehicle for over a dozen years in rain, snow, cold of winter and heat of summer? We could think all it needs is a weatherproof housing, as if we can ignore that seals on vehicles fail all the time. Do you refocus the cheap webcam thousands of times every day like the human eye may, to focus on objects at different distances?

Can you travel through time to put today's inexpensive webcam on a vehicle in that grueling scenario then check it a dozen years from now? I find it extremely optimistic to think it will be reliable enough to trust your life on it and even if you plan on replacing your vehicle before it's a dozen years old, there's still the other vehicles on the road to contend with.

Essentially I wouldn't call it random failure at all, suspecting that most if not ALL of them would fail from heat, shock stress, or mechanical zoom mechanism faults within the lifespan of the vehicle unless they are very expensive and tested rigorously for years - certainly not today's cheap webcams. I'm not suggesting cameras will never be a good idea, only that we're not there yet and the risk and cost is too high to save a hypothetical 5% on fuel consumption except in niche applications.
Lots of things fail all the time. Manufacturers still can't even get timing chains right.