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Tesla Winds and Elevation Web Browser App
- Thread starter SomeJoe7777
- Start date
SageBrush
REJECT Fascism
I solved this with a spreadsheet some time ago and posted a thread. This was followed by smart people (I think by Saghost and Iklundin) pointing out that the problem is a simple maxima question solved with a derivative of the energy consumption function.
For people for whom the above is greek: (85-ish - headwind) mph
The car does not expose elevation data through the browser's API, so code running in the browser does not have the elevation data available.
WRT the optimization question. It's pretty clear to me that the optimality criterion would be maximum rage per Whr.
The vehicle is held back by drag force D(g, h) in which g is the vehicle ground speed and h is the headwind speed, and frictional forces F(g). Note that D is a function of the square of the sum of the ground speeds and headwind speeds while the frictional forces are not dependent on h. Note also that the frictional forces are probably not linear functions of g. As work is force times distance D + F is the work required per unit distance traveled. This work must be supplied by the motor which is less than 100% efficient. Thus the energy required to travel a unit distance is ( D(g, h) + F(g) )/e(g) in which 0 < e(g) < 1 is the efficiency of the motor(s) (joules mechanical energy delivered per joule of electrical energy consumed). This is the quantity to be minimized. There isn't much one can do about h except wait for head winds to die down. At higher g + h, D dominates and efficiency is good. As g becomes smaller the motor(s) decreases and D is reduced dramatically (as the square of the g + h). At these lower speeds decreasing g further results in less improvement than the degradation from the loss of efficiency in the motor and ( D(g, h) + F(g) )/e(g) actually goes up as speed is reduced further. Range vs energy curves for these cars are generally speaking parabolically shaped. The sweet spot (minimum) is, IIRK, around 25 - 50 mph. So if you find you are cruising along and it looks as if you are going to be 10% shy on range decrease speed by 10% and gain approximately 20% range.
The vehicle is held back by drag force D(g, h) in which g is the vehicle ground speed and h is the headwind speed, and frictional forces F(g). Note that D is a function of the square of the sum of the ground speeds and headwind speeds while the frictional forces are not dependent on h. Note also that the frictional forces are probably not linear functions of g. As work is force times distance D + F is the work required per unit distance traveled. This work must be supplied by the motor which is less than 100% efficient. Thus the energy required to travel a unit distance is ( D(g, h) + F(g) )/e(g) in which 0 < e(g) < 1 is the efficiency of the motor(s) (joules mechanical energy delivered per joule of electrical energy consumed). This is the quantity to be minimized. There isn't much one can do about h except wait for head winds to die down. At higher g + h, D dominates and efficiency is good. As g becomes smaller the motor(s) decreases and D is reduced dramatically (as the square of the g + h). At these lower speeds decreasing g further results in less improvement than the degradation from the loss of efficiency in the motor and ( D(g, h) + F(g) )/e(g) actually goes up as speed is reduced further. Range vs energy curves for these cars are generally speaking parabolically shaped. The sweet spot (minimum) is, IIRK, around 25 - 50 mph. So if you find you are cruising along and it looks as if you are going to be 10% shy on range decrease speed by 10% and gain approximately 20% range.
I've seen this myself, this appears to be problems with the Model 3's browser implementation. You can keep trying and eventually both will verify, or you can manually enter the URL in the browser as follows:
Code:
https://teslawinds.com/?ownAPIK=[OpenWeatherMap API Key]&gnUN=[GeoNames Username]If you enter that URL manually, insert your OpenWeatherMap API Key into the proper spot in the URL (no square brackets), and also insert the GeoNames username (also no square brackets). If this is successful, the application will load, then bookmark the page.
israndy
Supercharger Hunter
I first did it on my Mac. Once I was comfortable that I had the URL then I transcribed it letter by letter into the car, and as was said I bookmarked it and it's worked flawlessly since. Though the browser keeps crashing and I have to reboot the car. Doesn't seem to be TeslaWinds that is the problem.
-Randy
-Randy
Unfortunately, I was never able to find overhead-view graphics for any Tesla other than the Model S. And the only one I could find was white with pano roof. If someone has some high-quality overhead graphics of the other vehicles or colors, I might be able to implement that as an option selection.
My question a with regard to getting the app running - the other guy was interested in the graphics.
When I enter
Tesla Winds and Elevation API Key]&gnUN=[GeoNames Username]
as the URL the app tantalizingly shows the graphic for a second or two and then puts up the page with the empty slots into which one is supposed to enter the keys.
When I enter
Tesla Winds and Elevation API Key]&gnUN=[GeoNames Username]
as the URL the app tantalizingly shows the graphic for a second or two and then puts up the page with the empty slots into which one is supposed to enter the keys.
israndy
Supercharger Hunter
If you enter the keys it will then take you to the full URL that is needed to invoke the app to run. Just put in your keys and then bookmark the result so you don't EVER have to type those again.
-Randy
-Randy
Jeff Hudson
Lovin the Tesla Life
After using this for over a year in my Model S I activated this web site/service in my Model 3. Please note there is a single letter typo in the code above. It should read:
Code:
https://teslawinds.com/?owmAPIK=[OpenWeatherMap API Key]&gnUN=[GeoNames Username]The single letter typo occurs in the text "owmAPIK" and by the way, for what it is worth, I used the same OpenWeatherMap API Key I created over a year ago.
Jeff Hudson
Lovin the Tesla Life
Good luck and keep trying because the information it produces is worth the peace of mind when driving on unfamiliar terrain during a trip.
Eureka! Tried again and it registered right away. And it displays wind data. I recognize that the wind it gives me at a given spot is doubtless that interpolated from the METARS of the nearest airports and perhaps including Weather Underground amateur stations and only updated every 10 minutes so I am not too surprised that it tells me I am in a 8.9 mpH wind field when the leaves on nearby trees aren't even rustling.
It always says the elevation is -1000 ft and the Next Position Update field always shows ---. Is that normal?
But it did tell me I had a stiff tailwind for a trip that turned in 266 Wh/mi consumption (X).
It always says the elevation is -1000 ft and the Next Position Update field always shows ---. Is that normal?
But it did tell me I had a stiff tailwind for a trip that turned in 266 Wh/mi consumption (X).
Jeff Hudson
Lovin the Tesla Life
Great reporting. In my experience the TeslaWinds website reports what it can and sometimes that is nothing. I do not recall a negative elevation being reported. I will say that out on an interstate highway between widely separated areas of appreciable populations there is no elevation or wind data for the website to collect. This can be problematic if you are stretching your vehicle range but you can always stop and get out to assess the wind speed and direction. 
Range limiting due to rain is pretty much self evident as is temperature. The EV Trip Planner website can come in handy as well when traveling.
Range limiting due to rain is pretty much self evident as is temperature. The EV Trip Planner website can come in handy as well when traveling.
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This was in the DC metro area. It knows where the car is generally as the wind reports are labeled with the general location e.g. Washington DC, Fairfax County, Tyson's Corner, McLean etc. but doesn't seem to know where it is precisely enough to pull elevation data from the databases. And that's not surprising as it never solicits a position report.
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