Stories
Slash Boxes
Comments

SoylentNews is people

posted by Fnord666 on Thursday January 02 2020, @04:15AM   Printer-friendly
from the What-could-possibly-go-wrong dept.

Mirrors have been an integral part of motor vehicles for over a century. The low tech solution has solved the major visibility issues involved with driving and now car makers think they can do one better using cameras instead of mirrors. This may be an improvement in large trucks where visibility using mirrors can be poor to the point that obstacles directly in front and behind the vehicle cannot be seen but for cars it may prove to be a theft opportunity.

Best not to mount a mirror, or indeed a camera, directly in the line of fire of a neighboring car door in the parking lot. Maybe someone should tell them about the practicalities of life?


Original Submission

 
This discussion has been archived. No new comments can be posted.
Display Options Threshold/Breakthrough Mark All as Read Mark All as Unread
The Fine Print: The following comments are owned by whoever posted them. We are not responsible for them in any way.
  • (Score: 0) by Anonymous Coward on Thursday January 02 2020, @06:04PM (4 children)

    by Anonymous Coward on Thursday January 02 2020, @06:04PM (#938715)

    You don't get good depth perception like that, hence the warning that objects in the mirror may be closer than they appear. That's because mirrors aren't flat, they distort the image in order to give more angle of view.

    In terms of perspective, I take it you haven't used one of those new cars with the back up cameras. The one I've seen has lines on it to give a sense of perspective to the viewer. They show slanted lines for directly behind as well as secondary lines to show where the car is going to go if you straighten up the wheel and drive straight back. I see no reason why side view mirrors couldn't have some similar adjustment to help the driver understand that.

    Also, keep in mind that most cars are coming with secondary sensors to warn about when the car is going to collide with something behind it. If you've got that, which is likely more accurate than your personal depth perception anyways, why would you need the extra layer of security?

    I've been parallel parking behind a car that was parked too close for the last few weeks and it's really tough to know how close you can get with the current set up of mirrors as I couldn't actually see the car when I was getting close, I'd have a couple more feet than it seemed. With cameras, I wouldn't have that problem as I'd be able to see the car until just before I'd hit.

  • (Score: 2) by Unixnut on Thursday January 02 2020, @07:17PM (3 children)

    by Unixnut (5779) on Thursday January 02 2020, @07:17PM (#938757)

    > You don't get good depth perception like that, hence the warning that objects in the mirror may be closer than they appear. That's because mirrors aren't flat, they distort the image in order to give more angle of view.

    Sorry, but I don't agree. For one, mirrors are by and large flat. In fact I checked the wing mirrors on all my cars just now, and they are mostly flat(*), just tapering off at the corner (the rear view mirrors are completely flat). I also don't have any warnings about "objects may be closer than they appear". Even so, it is not the flatness that gives you depth perception, but the shifting of the image by bopping your head around. Even if the mirror is distorted, you can still compensate. Indeed I never even noticed that the mirrors were not flat. Just now, I had to actually hold up a thin stick against the mirrors and move it across to even notice some curvature.

    (*)One does have a strongly curved bit on the bottom right of one of the wing mirrors, but that was an aftermarket part fitted by a previous owner, because the car has the steering on the wrong side for my country, so the wider view helps when pulling out of spots, and yes being able to judge distance on that little mirror is nigh on impossible. Thankfully I got the rest of the wing mirror to aid me there.

      > In terms of perspective, I take it you haven't used one of those new cars with the back up cameras. The one I've seen has lines on it to give a sense of perspective to the viewer. They show slanted lines for directly behind as well as secondary lines to show where the car is going to go if you straighten up the wheel and drive straight back. I see no reason why side view mirrors couldn't have some similar adjustment to help the driver understand that.

    Yes I have used them, and I find it is a poor replacement to the rear view mirrors or, turning your head when you are reversing (which is how I was taught to reverse, that you should face whichever direction the car is going).
    For one thing you can only see what the camera sees, so if there is something out of the cameras field of view, you can't see it unless you turn your head round. I once had the shock of my life when a kid ran behind the car as I was reversing, had I been able to use the rear view mirror I would have noticed the kid on the edge. This way until the kid was already in view of a camera I could not see him. The only reason I managed to stop in time is because the car still had normal wing mirrors, so I caught a glance of movement before the kid reached the rear.

    Secondly I have had the camera get coated in mud/dirt and be effectively useless, or have bright sun wash out most of the view, to the point where you are reversing blind and waiting for the ultrasound sensors to tell you when you are about to hit something (and I have had them not alert me, resulting in a me hitting a pole).

    I can list other problems with it, but in may ways it is an excellent example of overcomplicating. Even if the reversing camera was as good as a mirror, it is still the worse choice, because you have replaced a simple piece of silvered glass with rear view cameras, multiple ultrasound detectors, LCDs and all the computers + software/firmware to do the same job, each of which has far more potential failure modes or error conditions.

    Yes, if it was a magnitude of an improvement over the mirror it might be worth it, but as it stands it is the same to worse than what it replaced. There is no benefit to overcomplicating things. Simple and elegant to do the job wins the day, it is the keystone of good engineering.

    > Also, keep in mind that most cars are coming with secondary sensors to warn about when the car is going to collide with something behind it. If you've got that, which is likely more accurate than your personal depth perception anyways, why would you need the extra layer of security?

    (a) extra layers of security are always a good idea, especially if they are cheap to implement and not prone to failure, (b) like I have mentioned above, I have had the sensors not tell me about obstacles behind me, resulting in bumper damage. The problem is that the sensors didn't fail (which would have alerted me on the dash), they just did not register the object, and I trusted them. I have never had that happen with mirrors, or just looking behind me, and (c) so far my depth perception seems to be better than they are. The sensors usually start saying I am going to hit the object while there is a good 30cm left of space. I can generally get much closer to objects when I don't rely on the sensors.

    That is not to say they are a bad thing. That is an example of not too much complication. Relatively simple, cheap/easy to maintain, generally work even if dusty/dirty and are only an aid, not a replacement to the mirrors.

    > I've been parallel parking behind a car that was parked too close for the last few weeks and it's really tough to know how close you can get with the current set up of mirrors as I couldn't actually see the car when I was getting close, I'd have a couple more feet than it seemed. With cameras, I wouldn't have that problem as I'd be able to see the car until just before I'd hit.

    I don't know what to say about this, except that maybe you need more parking practice? If your mirrors are curved to the point where you can't judge depth properly that would make your life harder. Can you get flat mirrors for your car? Secondly have you tried turning your head round to reverse? With practice that may help you. I learned to drive/park in a dense urban environment, where having 15cm of gap to squeeze your car in was the norm. Having a few feet out sounds like luxury :-)

    Saying that, mirrors are used for a lot more than just reversing/parking. They are excellent for checking behind you before you brake, as they are for checking oncoming traffic when pulling out or overtaking. The ability to move my head and see different views in an instant has saved the lives of a few (motor)cyclists barreling behind me when I am about to pull out. From time to time they manage to be in my blind spot, which I can only see if I lean forward, shifting the mirror view to the blind spot area.
    In these situations sensors don't help, because by the time the object gets close enough for them to register, get processed, alerted on the screen, and for the driver to see/parse/act on the warning, an accident would already have occurred. Cameras would not be able to be altered in such a way by learning forward to check blind spots or places not already in the cameras field of view.

    In fact, as more and more people are cycling, the mirrors become more and more important, which is why as part of everyones driving lessons, is the concept of "mirror-signal-maneufver", checking mirrors should be unconscious and automatic.

    • (Score: 0) by Anonymous Coward on Thursday January 02 2020, @08:23PM (2 children)

      by Anonymous Coward on Thursday January 02 2020, @08:23PM (#938792)

      You're an idiot. Yes, side mirrors often times are curved so that they can show more than what you'd see with flat mirrors. Bobbing your head works to an extent, but bobbing your head distracts from actually operating the vehicle. Yours may not be, but that doesn't mean that they all are. As far as parallel parking goes, you are a fucking moron. You cannot see what's directly behind you. You try parking in front of a car with a short front end that's blocked by the rear of the car and see how well you do. I happen to be great at parallel parking, but at a certain point you need to see the fucking car behind you in order to park in a tight spot. There is no arrangement of mirrors that is going to make that magically work. A camera system makes that child's play by default as you can see the car. Curve or no curve, mirrors don't always work out.

      As far as the glare goes, is that really that much better than looking? I've regularly had issues with visibility due to the angle of the sun. Especially during the winter when half the time the sun is up, it's so low in the sky that it's coming in practically flat. Meaning that, it will be directly in the mirrors anyways. Camera or no camera, it's going to be an issue. Mud is a potential problem, but by the same token, if it's getting all over the camera, you've got it installed incorrectly. It's supposed to be somewhere behind the wheels, not in front of them where the mud is splattering all over it.

      • (Score: 2) by Unixnut on Friday January 03 2020, @02:39AM (1 child)

        by Unixnut (5779) on Friday January 03 2020, @02:39AM (#938922)

        > You're an idiot.

        Aaah, the "ad-hominem" attack. The last refuge of the weak minded, who, when they realise they lost an argument and cannot accept it, will resort to personal insults in lieu of intellectual discourse.

        Alas, I don't waste my time with such people, and as such I did not read your message beyond the quoted three words, and nor will I read any further messages you send on this topic. Thanks for playing, and next time either provide a reasoned argument in a civil manner, or don't respond at all. Either option is better than the above.

        • (Score: 0) by Anonymous Coward on Friday January 03 2020, @02:46PM

          by Anonymous Coward on Friday January 03 2020, @02:46PM (#939065)

          That's not an ad hominem, it's an insult. Please, don't use terms that you don't understand. An ad hominem is something like, your opinion on abortion doesn't count because you're a priest.

          And the feeling is mutual, you said some incredibly stupid things in your post. They are inherently stupid, there is no ad hominem argumentation in the post. But, you're too fucking stupid to recognize it. This is the internet, get over yourself pussy.