Auto design questions

Factual Questions
1

  1. Why can’t (or don’t) automakers design rear-view mirrors which when adjusted completely eliminate blind spots? Is it a limitation of optics or a business/cost decision or what?

  2. Why no front-window defoggers? My rear window is always clear with the rear-window defogger well before the motor has warmed up enough to start blowing warm air on the windshield. The big argument I would see against it would be sisibility issues (wires across the windshield obscure vision) but even a fe widely spaced wires would seem to be an improvement over the current sit-and-wait.

2

Field of view isn’t wide enough. You’d have to have a distorted mirror to eliminate blind spots on most vehicles. That said, you can adjust your side mounted mirrors to eliminate blind spots. But you’re still better off checking yourself by turning your head.

Chrsyler minivans are one vehicle that I know of that have electric defrosters. Granted it’s just to free up the windscreen wipers without burning up the motor.

Defroster should work just about instantly. Try turning on your A/C compressor if it’s a separate switch. Most modern cars do this for you automatically, but you never know.

Of course, if you’re talking about frozen fog inside the car, then in my own little experience it takes just as long for the rear to defog than the front.

Results may vary.

3

As I understand how the car heater works (and I’m probably wrong), it relies on heat from the engine to heat up air which is then blown into the passenger compartment. I drive an '03 Altima and as far as I can tell it doesn’t have any sort of auxilliary heating system for the defroster so it’s taking ambient temperature air and heating it up. It always takes way longer for the front window to clear than it does for the rear window to defog, and this has held true for every car I’ve owned or driven with rear-window defoggers. It seems like a no-brainer to assist the blowers, either by somehow heating the air through a separate heater (which would probably be some sort of fire hazard) which would have the added bonus of heating the car itself faster, or to clap a few wires on the windshield for defogging purposes.

4

Eliminating blind spots: http://cartalk.cars.com/Columns/Archive/2002/November/07.html

5
      • You could get a 5-mirror array for a few cars once–one was the Renault R5/turbo, the turbo a spiffy little ride if you can find one. -The R5 Turbo was the car shown in the print ads for the mirror, anyway. It had 5 regular-sized mirrors, arranged all the way across the ceiling, each separately adjustable. There was a couple other cars it was made for also–it is contoured to fit into the front of the ceiling and had a solid exterior–it wasn’t just 5 little stems, each with a mirror. Owners said it worked great during the day, but they also complained that the headlight glare from cars behind at night was near-blinding.
        ~
6

Ford (and maybe others) offered an “Insta-Clear” windshield as an option back in the 80’s. The windshield actually had a micro-thin layer of metal bonded into it (like solar glass) which got a shot of current running through it to heat and defog the windshield in a few seconds.Defrosting was quick, too, although you still had to scrape ice.

Only problem was, when the windshield got cracked or broken (which happens a lot more frequently than the rear window) the damn thing cost like $1,000 to replace, instead of the $300 or so that a plain glass windshield cost. Some drivers also complained of glare problems from oncoming headlights.

Clamping a wire grid on the front windshield is probably impractical because a) it would hinder visibility and b) idiots would jump in and drive while they still had the veneitian blind effect you see on rear windows in freezing rain or really cold days.

7

I’ll clarify what I meant. If your back window and front windshield are fogged, there’s no noticeable difference between using the wire heating element in the back and the dehumidified air in the front. I never see a difference, anyway. If the fog is frozen, though, then it still takes about as much time to get both perfectly cleaned. In the back, though, you can usually see well enough with about 10% of the ice gone.

If you’re talking about outside ice freezing on the windshield, well, that’s what ice scrapers are for. Although I’m usually too lazy and then just wait the long time for the engine heat to kick in.

8

for blinds spots - TURN YOUR HEAD, but do it very quickly, cuz the car in front of you might hit the brakes for no reason ( people are id1ots ).

9

its hard to turn your head far enough to see what appears in the mirrors, but easy to turn it enough to cover the blind spot.