Originally Posted by oldgoat
ACC would be appropriate on crowded snow covered roads where the speed of traffic is below the safe speed for a single car. On I80 from Tahoe to the valley in a storm for example--although the way my wife's car brakes instead of slowing down makes me nervous. On an open snowy or icy road with curves of any kind obviously it's not appropriate. Which brings up:
There certainly could be lane markers that could be implanted in the road and detected by the car. Currently on I80 this technology is used by the snowplows--I think in that case it's magnetic--so that the plows can go while blind. The bigger problem for a self driving car in the snow would be for the car to figure out what speed is safe, especially going around corners, uphill vs downhill, slowing down before the exit ramp which is much slipperier than the interstate, etc, etc. The number of scenarios a self driving car would have to be able to figure out is enormous and I think people who are predicting them any time soon are overestimating the intelligence of the programmers and underestimating the ability of even the densest human brain to make decisions on the fly. But who knows--people thought the car would never replace the horse. People also thought we'd all be in flying cars and using jet packs by now. Sometimes we're right about the future sometimes wrong. The self driving car doesn't have to be perfect of course, it just has to be safer and less likely to get lost than a human driver, but I believe people will insist on it being perfect, which will slow down implementation.
Well, no, you can't currently broadly recommend the use of ACC in winter road conditions, even in the situation(s) you describe.
The 1st link is to AAA's general article. They provide general ratings on ACC (not very high). No mention of winter driving.
2nd link is about using ACC in the winter & the potential problems of ACC reliability in those conditions.
3rd link is from a Honda manual. It specifically discourages relying on ACC in winter road conditions.
The issue is the sensors. The best ACC systems employ cameras and radar sensors to track proximity and lane position. They work together along with other sensors (eg: accelerometer, aspect, traction) to monitor the dynamics of the vehicle in motion and proximity to potential obstacles. Snow/fog/ice/grime can impair the cameras (on Subarus with Eyesight ACC, this will cause the ACC system to alert you of the problem and it will disengage). Icy roads can be a challenge for even the best traction control systems. Not all ACC systems are the same with the same capabilities.
Where I live, the road grime alone (from sanding/rocking snowy roads) would surely foul the ACC sensor cams every time I drove up to the resort.
So, one really can't make a blanket claim that ACC, in general, is something everyone should use on snowy/icy roads - even in the situation(s) you specify. It may not be safe for specific makes/models. Maybe someday the technology will evolve enough to become indispensable for use in snow/ice with all vehicles, but it's just not there yet.
If somebody has an ACC equipped vehicle and are thinking about trying that feature in winter driving conditions, my suggestion is to check your owners manual (or check with your dealer) and confirm when it's safe to use the feature.