[beefield]

It is something that puzzles me that there is no-one talking about making lane markers reflective on a radio frequency that passes through water (liquid and frozen) without too much trouble and put a radar on those frquencies on the car. Is it because there is no such frequency (I doubt)? Or would that be for whatever reason prohitively expensive? Or something else, like difficulties in getting good enough resolution from radar or that there exist no such material that reflects those frequencies well enough?

[mikeash]

Many localities can't even be bothered to maintain their paint. It's been speculated that this is one reason why Tesla's Autopilot is so much better than Mercedes' supposedly equivalent system: Mercedes is testing their system on German roads with perfect markings everywhere, Tesla is testing theirs on California roads that haven't been painted since the Reagan administration.

[kamaal]

I can give you a better test environment, Come here and test in India.

If you can get your car to self drive here, I assure you, your car will run anywhere on earth.

[mikeash]

Now that you mention it, it will be really interesting to see what happens with self-driving cars in places like India.

[albemuth]

In winter driving, where the paint actually is matters very little.

[dzhiurgis]

I believe that should be solved with improvements in computer vision. We are probably decade or two away from parsing realtime 2x100 megapixel streams.

[placeybordeaux]

Who is gonna pay for that?

[infogulch]

We are, through the government, as usual.

Laying down some RF reflective paint/markers on the road wouldn't be nearly as expensive as other proposals (like embedding electronics or special wire underneath the road surface), it would be similar in expense to pavement markers[0] that are applied to some roads today, plus with a HUD it could even help human drivers in snow environments. Lots of places make special modifications to the road specifically for snow, and especially for snowplows.

[0]: http://www.highway-markers.com/pavement-reflectors/PM290.htm...