Tesla Takes The Lead On Dumping Door Mirrors For Video Cameras

Follow John

Tesla Model X

Tesla Model X

Enlarge Photo

The rear-view mirror has now been with us exactly 100 years, having first been introduced in 1914, and it hasn't changed much in all that time.

It's a small area of mirrored glass--three of them now, actually--for the purpose of seeing through the rear window or along each side of the car without the driver having to turn his or her head more than slightly.

For decades, concept cars have shown one or more of these mirrors replaced by video cameras that show real-time images on a small display screen the same size as the mirror.

Tesla taking lead

Now Tesla Motors [NSDQ:TSLA] appears to be one of the companies taking the lead in getting government regulators to update Federal vehicle standards to permit such a replacement on production vehicles sold to the public.

The goal for the electric car-maker is to eliminate a large source of aerodynamic drag from its future cars.

The mandated mirrors on the driver's and front passenger's doors increase the car's frontal area. Aerodynamics engineers spend a great deal of time in the wind tunnel to make air flow over door mirrors as smoothly as possible, to reduce the energy needed to overcome that resistance.

Concept drawings and some prototype versions of Tesla's 2015 Model X electric crossover utility vehicle do not have door mirrors, but use a tiny camera in their place with the images displayed inside the passenger compartment.

Tesla Model S Designer Franz von Holzhausen

Tesla Model S Designer Franz von Holzhausen

3 to 6 percent of total drag

On Friday, journalist Allison von Diggelen wrote that Tesla design chief Franz von Holzhausen told her the company is talking with "authorities" about getting the necessary permissions to replace door mirrors with cameras and electronic displays.

Tesla is presumably in discussion with the National Highway Traffic Safety Administration (NHTSA), which issues the Federal Motor Vehicle Safety Standards (FMVSS) document, first issued in 1967 and regularly updated since then.

While door mirrors may not seem like much of a big deal, both of them together--with a total area of up to 2 square feet between them--create 3 to 6 percent of a typical vehicle's total aerodynamic drag.

Eliminating them could reduce energy consumption as much as lowering the car's roof by almost half an inch.

The Volkswagen XL1 ultra-high-mileage two-seater uses video-camera technology instead of door mirrors, as von Diggelen notes--but it is not designed to comply with all parts of the FMVSS because it's not intended to be sold in the United States.

Cumbersome volume of rules

Von Holzhausen "bemoaned the cumbersome amount of regulations that prevent or delay innovative car design," the author writes, linking to an earlier interview she did with Tesla CEO Elon Musk in January.

Tesla Model X at 2013 Detroit Auto Show

Tesla Model X at 2013 Detroit Auto Show

Enlarge Photo

In that interview and a related video, Musk complained about the regulations and their specificity, including some points that cover headlamp design and elements of the dashboard user interface that he views as "completely anachronistic."

The discussion with von Holzhausen was published on Friday in Boldly Going, a portion of her "Fresh Dialogues" blog that covers her family's trip in their Tesla Model S from Silicon Valley to Los Angeles using the company's Supercharger network of quick-charging stations.

Hand mirrors for women drivers

Automotive historians note that the earliest known reference to a rear-view mirror being used in a car comes from 1906, when author Dorothy Levitt wrote in her book, The Woman and the Car, that women were advised to "carry a little hand-mirror in a convenient place when driving"

Doing so, Levitt suggested, permitted women drivers to "hold the mirror aloft from time to time in order to see behind while driving in traffic."

It would take eight more years for the first fixed mirror to show up on a production car. Vibration-free mounts and auto-dimming aside, not a great deal has changed in rear-view mirrors since then.


Follow GreenCarReports on Facebook, Twitter, and Google+.

Follow Us

Comments (39)
  1. Some way to eliminate that dreaded blind spot over my left shoulder is long overdue. If I can't have a cool radar map of what's around me, I'll take the camera. C'mon Tesla!

  2. I applaud Tesla for seeking to reduce aerodynamic drag as much as possible. I do so on my cars.

  3. If you adjust your side mirrors outward, there is absolutely no blindspots. Too many drivers have them aligned to see the sides of their cars instead of the lanes next to them.

  4. That's an interesting theory. I'm glad I don't have to ride with you. I'm sure the feeling is mutual.

  5. It's not a theory, it's a fact.

  6. Actually, you can eliminate the blind spot on the left side of a car by adjusting the side mirror outward and the inside mirror farther left. It takes some getting used to but it does work. I read about this a long time ago, I think on Click and Clack's CarTalk website.

  7. I agree with you. The adjustment is critical. However, it is the application that matters. We must look ahead of time. Too many side to side wrecks are to do "impulsive lane changing." Move before look! is far too common. Much like the bias of not stopping at stop signs, the move before look bias in lane changing is a killer.

  8. Many 2013/14 model vehicles already have video display integrated into the rear-view mirror (located on the front wind shield) to display imagres from a backup camera. The 2013 LEAF has optional side-mirror cameras (& front cam) to provide a "surround-view". With quality displays; reducing exterior footprint seems to be next logical step.

    Bonus: Add a black-box DvR to record last 30 seconds before an accident to help identify circumstances leading up to an accident.

    Fewer blind-spots can make for a safer future.

  9. @Brian Henderson: Yes, I have a friend that purchased a 2013 Leaf that had the optional cameras. The mirror positions are still required until the Feds change that.

  10. It seems a bit silly to use electricity to power yet another electronics system to replace simple mirrors just to reduce drag by a tiny 3 to 6 percent. It's a waste of time and money, if it was more like 20% fine, but 3 to 6...............

  11. Maybe we can rest assured that Tesla made a cost benefit analysis for energy consumption with a clear outcome: the mirrors have to go.

  12. Hmm, it's getting to the point where if you don't praise Tesla on this site your comment gets attacked. I was actually just talking cameras versus mirrors, I wasn't really thinking about Tesla in particular.

  13. I think you are misinterpreting the response. Tesla customers are paying $10k to increase their range from 208 miles to 265 miles. 3-6% of 265 miles range is NOT trivial to them. It IS trivial if you are already throwing away 75% of your energy in an ICE vehicle and there is a gas station on every corner.

  14. Getting a thumbs down isn't a response, it can be used to disagree, dislike, or some people use it to show bias. So yes I'm misinterpreting the thumbs down because its never quite clear what reason someone chooses to give a -1.

  15. Cameras use a fraction of a percentage of electricity that the extra drag of sideview mirrors at higher speeds causes to be used. For an electric car, a 3-6% improvement is significant. Other automakers get excited when they improve mileage from 28 to 30 mpg (6.7% improvement).

  16. Ok, I guess 3 to 6% just sounded underwhelming at first, but if the benefits out weigh power usage then it's fine. I'm not against the cameras, I actually have three cameras in my car already. I have a backup camera and two side view cameras.

  17. @ CDspeed: I disagreed but I certainly didn't rate you down (up in fact to counter the though shall not question Tesla nonsense).

  18. Chris O, I was replying to my own comment after all the thumbs down I received. It wasn't directed at you.

  19. The cameras probably use under 20 watts. You are simply misinterpreting the kind of power consumption at stake here.

  20. Ok but what does a mirror use? Exterior mirrors are electronically adjustable and some offer a dimming feature for night driving. A camera system would have to run constantly whereas a mirror is just a mirror. And what do you think the cost difference is, will it cost more or about the same?

  21. The issue is not how much power mirrors use, but how much they lose. A decrease in drag will improve your miles/kwh efficiency. For a ballpark etimate, 3.8 mi/kwh at 60mph is an average draw of 16 KILOwatts. A 3% improvement would mean almost 500 watts saved while running at speed. Adding a 20-watt camera (and that is very generous for two CMOS cameras and little screens) would be a drop in the bucket by comparison. The extra draw at low speeds is acceptable because you only need all your range when you're on the highway.

  22. @ Tom, ok I apologize my mistake, I have been looking at this the wrong way.

  23. Well 3-6% is actually quite a lot the more mileage you can on the car. On top of that, Mirrors are one of those things that can be broken off by someone driving a bit too close for comfort.

  24. Mirrors scare me.

  25. There have been back-up cameras on cars for many years now. Is anyone aware of any reliability data? Even a cracked mirror can still do much of its job - it's very fault tolerant compared to an electronic camera + display, but that may be acceptable if there's negligible need for fault tolerance. Regardless, I won't be surprised if a segment of the population becomes a little too dependent on the cameras for their situation awareness...

  26. I do know when BMW first came out with a backup camera there was an issue where the camera wouldn't work if it got too hot. Though I think that only happened early on.

  27. Actually, for those of us in wintry climates, snow, slush, and ice frequently cover the lens of backup cameras. On the other hand, they're often at the back of the car and sometimes low (in the bumper, or next to the license light), so they're most vulnerable to slush kicked up at the rear.

    A better check might be Honda's new right-hand mirror with built-in camera that shows an image of the blind spot on the right on the dash monitor. It's a smart feature and has tested very well in consumer clinics, almost one of those, "Gee, why didn't anyone think of this before?"

    Whether THAT camera gets covered in dirt or snow or whatever might give a sense of the proposed system's vulnerabilities.

  28. I actually never experienced the issue with heat, it was in a few reviews about the car I had at the time and I haven't heard of the issue since. But my rear camera does get obstructed by dirt washed over it by rain. I also have side view cameras but they manage to stay pretty clean.

  29. its possible to have several cameras around the car and synthetically merge the visual sources.

  30. I've been using video mirrors for years on my xA, and they have significant advantages, and some disadvantages. Once I clear the ice and snow after a storm, they never get blocked again. Most rain storms are also fine, though occasionally the lens needs wiping clear.

    In rain and fog my video mirrors work *much* better than optical mirrors - they give a much clear view. Optical mirrors and the side window fog up and both are covered by water drops, and with glaring headlights, you see basically nothing.

    They have saved me significantly on gas, and they are noticeably quieter. Bright sun is the biggest challenge.

  31. I'd like to see the mirrors go...but Tesla faces more than just government regulations. There will also be resistance from those who are used to driving using the mirrors. Perhaps to satisfy as many as possible there could be fold-in mirrors that are flush with the body of the vehicle and could be pulled out at the driver's convenience or in the event the cameras have some sort of glitch.

  32. it would be possible to make the mirrors vestigal with a small round convex mirror and the camera mounted just below that. they would be much smaller and serve as a emergency backup, in case the camera goes down.

  33. My mirrors have had a technical glitch twice in the last couple of years when they got too close to an immovable object.

  34. That's a good point. Everyone I know has had a mirror ripped off their parked car--stupid college town drivers. If there were no mirrors to get ripped off, there would be a lot less hit-and-run damage.

  35. No mirrors on the outside would also provide a great wind noise reduction.

  36. I wonder if Tesla could incorporate the side mirror cams into the aft part of the side blinkers on the front fenders and reduce wiring complexity at the same time. The vestigial bumps where the side cams are currently could then go away leaving purrfectly smooth A-pillar lines. This would make the side mirror absence out of sight, out of mind.

  37. Removing side mirrors also reduces wind noise. The Volt has an issue with its very aero mirrors. You can buy replacements that reduce wind noise but they are less aerodynamic. Go for it, Tesla!

  38. I had thought that up maybe 10 years ago, but didn't think it would ever get through the regulatory process plus, selling a car manufacturer on the idea isn't easy and I figured it had to have been thought of by dozens of people.

    I'm just happy it's finally getting implemented.

  39. I want to use them, too in CarBEN EV5. I have been using them for years on my xA, but I have to remount the stock mirrors to pass inspection. The thing I hope that Tesla can do (besides getting these accepted) is to correct for barrel distortion.

    Video mirrors work very well in the rain, and at dusk. The cameras I have are most tested in bright sunshine, and by headlights - though they do not shine headlights in your eyes.

    High(er) resolution cameras with more "f-stops", and larger screens that are powered all the time you are in the car (for seeing out while parking on the street) will negate the weaker aspects, and the stronger points more than make up for them.

    I have no blind spots with 120+ degree view. They save lots energy.

Commenting is closed for old articles.

Get FREE Dealer Quotes

From dealers near you

Find Green Cars


© 2015 Green Car Reports. All Rights Reserved. Green Car Reports is published by High Gear Media. Send us feedback. Stock photography by izmo, Inc.