BW5

I'm looking for someone who knows about the range ring that shows on the map
...that weird irregular 'circle' when you zoom out that indicates how far you can go base don the current SOC....

Just hoping to learn more about it....
Is it just an artistic depiction that doesn't mean much?
Is it actually running what-if calculations on various roads?
...and how good is it?...is it taking speed limits, elevation changes, etc.. into account?
( I understand about the GUESS in the guessometer, limitations with assumed future driving will match the recent past, etc......but just trying to get an understanding of what variables they are considering in that guess)

for example, there might be a little finger protrusion from the circle that extends the ring to a slightly longer range, and sometimes that finger sort of hooks around an out of range area...sort of like how a similar range ring for an airplane indicating glide distance might show a hill out there near max glide.... Is that little finger really something or more of an artistic dramatization?

Also, it seems to have a charge cushion built in.... playing with it I navigated to a town that was safely within the ring but very close to it.... the route planner came up saying that I had insufficient charge and started suggesting charging stops... why is that?
I was thinking that perhaps it was because I would have arrived in that town with say 5% but it has some arrive with no less than 10% type of a safety factor.

A4 Phil

Excellent question. The blue range ring is dynamic and constantly recalculate based on your current efficiency and outside dynamics like traffic and temp (not wind ), elevation change and road type. The biggest downside of the range ring is that it is VERY conservative and has a buffer somewhere around 10%. The other bummer is that it does not grow on the NAV MMI while you are charging. So you have to exit out and re enter in order to see the new area covered while charging. I use this technique sometimes because the silly MMI will not tell you what you need to charge to to make the next way point.

I actually have an email into Audi to get the math behind the MMI, but I am not convinced I'll ever see it. I am signed up on the insider/beta tester version of the MyAudi app, and there was a note there around Christmas that the app would start showing a range ring for the etron. That not disappeared.

BW5

so you think it's actually estimating road by road?.... that that little finger protrusion example I made earlier is a road that's allowing me to travel further than some other road nearby...
If that's the case I wonder how granular it's getting... as in down to neighborhood streets? (not that it matters, just out of curiosity)

and you think it's got a buffer of maybe 10%...meaning that the "real" range is really 10% beyond the ring? Or that it limits you to 10% inside the ring?
the later would make sense for my example navigating to a town inside the ring but requiring a charge stop...... If the "real" range is beyond what is depicted, then if I'm right about having a battery SOC buffer built inside o the ring, means that it is extremely conservative!

I'm going on a short road trip in a couple weeks. I think I'll pay a little closer attention to it....take note of where along my route the ring ends, and when I get close to it note my actual SOC (and/or guessometer range remaining). Give me at least one or two data points to do some estimating with...

and yeah, that would be awesome if you could get that algorithm!!!

sor

I think the fingers mostly just follow the roads. For example, we have a giant lake in our area that you’d have to drive around. It makes no sense to just show a circle (range “as the crow flies”) and measure range across the lake when you have to drive around it and the actual distance traveled is twice as long. Similarly if there are areas of wilderness or no roads, it figures out range taking into account that you have to go around that area.

So it just calculates your current range but traces distance along the available roadway paths rather than using your range as a simple radius.

BW5

Just to continue the thought...
I did a short road trip over the weekend, something around 330 miles round trip...and gave this topic a little thought. I rarely run my range down very low so this trip gave me some opportunity.
Sadly I topped up for a little cushion on the way, and ended at this waypoint with my lowest SOC of 17%. It would have been interesting to take it much closer to the max range to see how the shape shifted in the last few miles

anyway
I feel like they are doing some rather heavy data fitting (like a least squares method of some sort?) and heavy data smoothing. I really doubt that they are running what-ifs for every possible road combination...or that they are even doing it for a large fraction of the possibilities.
Notice how the range ring places an artificially generated wavy line just off the beach along the ocean where clearly an as the crow flies radius would extend far offshore.
I think that it is likely looking at a simple circle around the current location, with radius defined by the guess-o-meter's number....then applying some sort of wavy line to indicate "approximate"...and it probably just bends that wavy line based on some running average of major primary roads generally bisecting the circle near the range circle, and generally truncates the circle for things such as the Atlantic Ocean.
...not even close to looking at every potential route between the present location and 'there'...in fact I think some of that bending or averaging pushes the long range "fingers" away from the actual roads in some cases

looking at his example (17% SOC)
the road heading North through St Mary's is I-95
the bump out pointing to roughly 1:00 towards "Bells River"... I seriously doubt that I could travel further out there where there's nothing... than I could sticking to I-95.... or ditto the road extending towards the 11:00 position

All of this doesn't really matter for much I suppose...it's just very odd. Anyway, it sure would be interesting (just from a more or less trivial interest perspective) to know what their algorithm is looking at.

perlfather

After some simple experimentation, I believe the blue ring does recognize changes in elevation and adjusts the range accordingly.