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Thoughts About an Altimeter Ap

Discussion in 'Technical' started by wdolson, May 1, 2016.

  1. wdolson

    wdolson Active Member

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    My father has always had altimeters in his cars. He was in the USAAF in WW II and I think part of it was just being a fan of aircraft instrumentation. He passed down a car to me many years ago that still had the altimeter in it and I've moved it from cars ever since. The thing is 50 years old now.

    I ordered my Model S last week and was thinking about an altimeter. It may be time to retire the 1960s vintage unit and get a new one. I was looking around and there are small altimeters being sold to model rocket and drone flyers.

    Having done a fair bit of embedded firmware, it got me thinking of an altimeter ap for the Tesla. I know the center console runs on Linux, but I would have to interface the altimeter hardware in there some how and then write an ap for the console. With full access to the OS and the buses connected to the console it probably wouldn't be tough, but I think it might be tough to hack this one.

    There are a lot of people here with a lot more knowledge of Tesla's systems than I have and I was wondering if such a thing was even feasible with what is known among the Tesla enthusiasts today?
     
  2. ggr

    ggr Roadster R80 537, SigS P85 29

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    My old Mercedes (that I traded for the Model S) had an elevation readout on the map. The GPS knows your altitude already! It's not as accurate as the position, but within 100 feet. I've asked Tesla to put it on the info bar, but no response...
     
  3. wdolson

    wdolson Active Member

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    I hadn't thought about GPS. It would be nice to have that data available one way or another.
     
  4. JeffK

    JeffK Active Member

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    A vintage altimeter wouldn't necessarily work correctly unless it was mounted outside the car because it's essentially a barometer. With Biohazard defense mode you get positive air pressure inside the car and this might negatively impact the accuracy of a barometer based altimeter.
    GPS is probably the only way to go.
     
  5. jackbowers

    jackbowers Jack Bowers

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    Love the built-in altimeter on the Roadster. Tesla already has elevation data in trip planner so it would be an easy thing to add if Elon were willing, but I'm not sure he is.

    Here's a creative idea: Release 150 elevation announcement "songs" that have album cover artwork showing elevation to the nearest 100' up to 15k. Then develop an iPhone app that works off the GPS and plays the "song" corresponds to your current elevation. Then all you would have to do is call it up on the car audio system. If the car has an internet connection it would display the elevation via album artwork, otherwise you would be able to hear the elevation announcement.
     
  6. Ashkenaz

    Ashkenaz Member

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    The altimeter doesn't need to be mounted outside car, only the source of ambient air pressure. Aircraft have ports (static port) which is small hole allowing static air pressure to go to altimeter inside cockpit. Static port is typically mounted on side where there is no direct airflow.

    That being said, today's gps are so accurate they can give altimeter readings.
     
  7. cpa

    cpa Member

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    Gee, wdolson, why not include an anemometer and artificial horizon (for AP models) :cool:

    Seriously, I was joking about the artificial horizon, but an anemometer would be way cool, particularly for assessing additional charge needed on extremely windy days.
     
  8. wdolson

    wdolson Active Member

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    Unfortunately other aircraft instruments wouldn't be very useful, but they would be cool. I suppose you could put a pitot tube on the car and compare your "airspeed" to what the speedometer is telling you. It would tell you if you are bucking a headwind.
     
  9. Zextraterrestrial

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    I tried to put a pitot on my S and could never get it in a good spot where it got readings that made sense. I even stuck it ~1ft in front of the nose. Seemed turbulent, maybe my air tubes were bouncing or something? I tried the roof and mirror too. The altimeter worked fine but would lose calibration after a while + it is for an Rc so it starts at 0 which isn't too bad from an EV range perspective
     
    • Like x 1
  10. Ashkenaz

    Ashkenaz Member

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    Pitot tube -omg that's funny! I'm feeling very optimistic about joining the tesla club!
     

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