astrorob wrote:perhaps rather than trying to nail an exact number they could give a best-case and worst-case estimate. i think they are always battling between confusing the ordinary user with a load of information and simplifying the information too much. they seem to be painfully aware that they have to present the information in such a way that it can be understood by the average person, and not an engineer EV enthusiast. my personal opinion is that they are going to try very hard to come in on the conservative side of any estimate. the worst thing that could happen is that they tell you 20 miles are left and there's only 5 in real life. their lawyers probably worry about what could come of consistently overestimating the range...
Yes, this (best/worst case range) is something I would prefer over a SOC meter. To me, a SOC (in gids or %) means just another number I have to mentally convert into "how far can I go" and as was pointed out at the meeting, it's also somewhat of an estimate.
The currently displayed DTE is always some number that lies within a range of "best case" and "worst case" values. I have to believe that they can also calculate (with reasonable accuracy) those best/worst case values within which they are currently displaying the DTE guess. The problem is that we can't tell whether the currently-displayed DTE is optimistic or pessimistic (cf: earlier "bipolar" discussion).
Perhaps some clever bit of UI/UX engineering could result in a display that shows both of the best/worst case values (as calculated by the car), with some visual indicator (font size, or some other emphasis) as to which one the car thinks is closer to the truth. Or it could just display them both evenly and let the driver decide, since (especially for routes that the driver is already intimately familiar with) we likely know better than the car, which end of the range is more appropriate.
The problem with the current DTE estimate, as well as the Leaf's 12-bar SOC, is that even if you know how far you are from home (in SOC or miles), the car really doesn't give you any way to tell whether or not you can make it since you don't know how the DTE was calculated (as was pointed out with a concrete example at the meeting by Arnold).
I believe the current gid/SOC-meter could be programmed to display these two numbers -- as "High.Low DTE" instead of the gid or percentage. I'd probably choose (from the range chart) the 7/bar and 4.5/bar columns for best/worst, so 100% would show "97.62", 80% would show "80.51", 51% would show "50.32", and 26% would show "19.11", etc. (of course, the high/low data columns could even be user-configurable).