Or could the side mirrors could be shaped like an airplane's wing so that the air displaces nicely?
It'd look weird, but I'd rather have the fuel efficiency.
This sounds like a lot of overengineering - you need reliable low latency eye movement detection and a motor mechanism that can react that fast but withstand the air forces at highway speeds. Just to deliver a worse UI - imagine the complaints about how Tesla doesn't detect my eyes unless I look just right. But 6% fuel usage sounds like an enormous saving that would be worth some of your complexity budget.
But not sure that would be legal.
https://www.caranddriver.com/features/columns/a28120245/car-... (2019)
I want better cars. That doesn't necessarily mean that I want less-electronic cars.
I'm reminded of how far we've come every time I go out on a cold wintry morning and the electric starter cranks the electronically fuel-injected engine for me, and the whole thing comes to life with utterly-perfect reliability.
I can then select a gear and proceed. No particular warm-up period is required; it's running smoothly straight-away. The electronically-controlled transmission shifts smoothly. The heated seats quickly warm my tuches while the automatic climate control seeks to warm the cabin and maintain a stable temperature without any interaction on my part.
No messing with an ignition retard, or a manual choke. No need to prime the engine by giving it a few turns with the ignition switched off. There's no hand crank with which to break a jaw[1].
It's pretty great, I think.
But there's still plenty of examples remaining of the 15 million Model Ts that Ford built, for those who really seek to limit the electronics to almost-nothing. (And steam cars, too! We must not forget the simplicity of the Carnot cycle, nor of the carbide lamp!)
[1]: https://www.hemmings.com/stories/the-accident-that-started-i...
If you watch old American sitcoms one of the guys, typically a dad, will always be fiddling with his car and tune and maintain it. That was a stereotype for a reason.
I think we're definitely in a better place these days.
And I'll be thinking of this, and all of the money that I didn't dump down the throat of a carburated engine, the next time I get out my special bendy-ratchet (that articulates in two different places) and single-purpose crowsfoot socket to change an O2 sensor that has finally gone wonky after hundreds of thousands of miles. :)