On Autopilot / FSD - distance between cars

[davidkapell]

I would like the distance to automatically vary with the speed of my vehicle. Six car lengths at sixty mph. Five lengths at fifty mph. Etc. the auto setting could be an option.

 

[MLXXXp]

I would like the distance to automatically vary with the speed of my vehicle.

The following distance setting isn't in car lengths and does vary with speed. I'm not sure exactly what algorithm is used, though.

 

[rjpjnk]

Agreed. I can’t figure out what they are doing. But it certainly isn’t just distance in car lengths as the graphic suggests. Seems speed dependent and works pretty well whatever it is.

 

[KenC]

I've always assumed it was by time. That is, a setting of 1 is 0.5 secs, a setting of 7 is 3.5 secs. When I drive behind another vehicle, and it passes a line on the road, I count the time before I pass, and when I'm on 7, it's just over 3 secs.

Using time as the distance parameter, allows for different distances based upon speed, and of course, stopping distance is also varies upon speed, so time seemed to me to be the obvious variable.

 

[rjpjnk]

I've always assumed it was by time. That is, a setting of 1 is 0.5 secs, a setting of 7 is 3.5 secs. When I drive behind another vehicle, and it passes a line on the road, I count the time before I pass, and when I'm on 7, it's just over 3 secs.

Using time as the distance parameter, allows for different distances based upon speed, and of course, stopping distance is also varies upon speed, so time seemed to me to be the obvious variable.

Interesting idea. Could be true.

Since FPS = mph *(5280/3600),
Then each car length would increase following distance be (0.73*mph) feet.
So at 60mph the cars are 44 each feet long, and at 30 mph they are 22 feet long.

That seems a bit too long. Maybe it’s a little less than half a second each?

 

[Mash]

It's most certainly some multiples of time already and it's the most sensible thing to do

 

[EVRider-FL]

From the manual: “Choose a setting from 1 (the closest following distance) to 7 (the longest following distance). Each setting corresponds to a time-based distance that represents how long it takes for Model S, from its current location, to reach the location of the rear bumper of the vehicle ahead of you.”

 

[cobra]

Works pretty well. Has anyone noticed recent Autopilot on FSD Beta software seems to drift further away from leading vehicles after catching up? Pretty repeatable here and bothersome in traffic (around philly, not keeping up is a good recipe for getting cut off!) Seems like it won't maintain the distance here. Catches up to lead vehicle at a reasonable follow distance. Then slowly drifts further away (at moderate speeds, say 30-50), then after a while will catch up again. Seems to be a vision only thing, I'd guess.

 

[Dewg]

Works pretty well. Has anyone noticed recent Autopilot on FSD Beta software seems to drift further away from leading vehicles after catching up? Pretty repeatable here and bothersome in traffic (around philly, not keeping up is a good recipe for getting cut off!) Seems like it won't maintain the distance here. Catches up to lead vehicle at a reasonable follow distance. Then slowly drifts further away (at moderate speeds, say 30-50), then after a while will catch up again. Seems to be a vision only thing, I'd guess.

I have not had that experience - still on 10.9. It maintains precise distance to the car in front of me. If they speed up, I speed up. If they slow down, I slow down.

 

[cobra]

I have not had that experience - still on 10.9. It maintains precise distance to the car in front of me. If they speed up, I speed up. If they slow down, I slow down.

What model car? I wonder if it makes a difference.

 

[Dewg]

What model car? I wonder if it makes a difference.

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