Welcome to PhantomPilots.com

Sign up for a weekly email of the latest drone news & information

Bad idia in new firmware

Discussion in 'Firmware' started by skyhighdiver, Dec 19, 2013.

  1. skyhighdiver

    Joined:
    Dec 19, 2013
    Messages:
    1,007
    Likes Received:
    211
    Location:
    South Dakota
    2). Further improvement on detecting bad battery readings that may cause sudden landing (due to 'invalid battery' error).

    Battery readings should not even factor into the flight!
    its good to send us the info, its good to have a warning, but I don't want the machine to land itself unless it has lost signal.period
     
  2. Migmon

    Joined:
    Nov 27, 2013
    Messages:
    148
    Likes Received:
    1
    i flew mine to 3% today and didnt get this... not sure when its sposed to fly home
     
  3. jadebox

    Joined:
    Nov 20, 2013
    Messages:
    490
    Likes Received:
    51
    Location:
    Oviedo, FL
    I think you're reading that wrong. I think they are saying that the fix is intended to prevent a "sudden landing" (crash?) due to a bad battery reading, not force a "sudden landing."

    -- Roger
     
  4. garygid

    Joined:
    Dec 15, 2013
    Messages:
    294
    Likes Received:
    0
    Location:
    Laguna Hills, Orange county, CA 92653
    There are two different ways to estimate the remaining battery
    energy. The first is to just use the total pack voltage, but
    this provides only a rough estimate.

    Since one cell might be lower than the other two cells
    (in an unbalanced condition), the readings of all three of
    the cells is needed to make a better estimate of the usable
    energy remaining in the battery pack.

    When the battery's data contacts are not working, the
    P2V's internal flight controller will be getting no new data,
    which might be interpreted as zero remaining energy,
    so the flight controller might abruptly execute a forced,
    emergency landing, perhaps a poor choice for handling
    this situation.
     
  5. LeoS

    Joined:
    Nov 25, 2013
    Messages:
    747
    Likes Received:
    1
    When they program the logic of 'forced landing', it's generally because of 2 things:

    1. It doesn't know where 'home' is anymore (compromised gps) and it has lost control signal (can't get commands from you), so it makes a landing than taking a chance to fly 'home'.

    If you think about it, this condition usually happens when the phantom is sufficiently far enough from you (weak control signal)...
    so there's a much higher chance of it flying further away from you than picking the correct direction to fly home.

    2. It doesn't think it has enough power to safely maintain its altitude. Rather than risk a battery cutoff during flight which results in uncontrolled crash, it puts the phantom down in one piece for you to recover.
     
  6. iDrone

    Joined:
    Nov 14, 2013
    Messages:
    612
    Likes Received:
    2
    Location:
    Los Angeles, California USA
    As of v1.05 firmware, loss of data comm between SmartBattery & PV no longer initiates an auto-landing. Instead it throws a warning message to your iDevice and suggests you fly home ASAP. But PV still monitors the SmartBattery's output terminals and if it detects it dropping below 10.65v will initiate an auto-landing. This has been carried over to v1.08 firmware as well.

    iDrone
     
  7. Knighthawk

    Joined:
    Dec 17, 2013
    Messages:
    60
    Likes Received:
    1
    As far as it not knowing where home is and possibly flying further away - I could understand that if GPS was completely lost, but IMHO if it sees 5 or even 4 satellites, it should pretty well still know where home is. The PV uses it's own barometric altimeter to determined height, so basically the satellites are used for direction info only. Heck, even 3 could be enough for it to know where to go.
     
  8. garygid

    Joined:
    Dec 15, 2013
    Messages:
    294
    Likes Received:
    0
    Location:
    Laguna Hills, Orange county, CA 92653
    I agree, declaring that having only 6 locked satellites is a GPS in-flight failure
    seems premature to me too.
     
  9. skyhighdiver

    Joined:
    Dec 19, 2013
    Messages:
    1,007
    Likes Received:
    211
    Location:
    South Dakota
    agree as well better to come home 20ft off than to just land a mile away or in the middle of a lake
     
  10. LeoS

    Joined:
    Nov 25, 2013
    Messages:
    747
    Likes Received:
    1
    If the answer is that simple, why do you suppose DJI does not implement that?
     
  11. garygid

    Joined:
    Dec 15, 2013
    Messages:
    294
    Likes Received:
    0
    Location:
    Laguna Hills, Orange county, CA 92653
    Perhaps they chose to keep the hardware and software propriatary,
    so that we cannot help them find bugs, and provide improvements?
    Of course, that is partially a liability issue.

    They do not have enough programming or design experience
    to catch these bugs?
    Probably they were rushing to market to get this Christmas
    buying spree, and ran out of time for sufficient QC.

    Perhaps they are saving some features and improvements
    for their next model?
    Many times each product is crippled a bit, just to leave
    room for other more-expensive products.
     
  12. skyhighdiver

    Joined:
    Dec 19, 2013
    Messages:
    1,007
    Likes Received:
    211
    Location:
    South Dakota
    As of v1.05 firmware, loss of data comm between SmartBattery & PV no longer initiates an auto-landing. Instead it throws a warning message to your iDevice and suggests you fly home ASAP. But PV still monitors the SmartBattery's output terminals and if it detects it dropping below 10.65v will initiate an auto-landing. This has been carried over to v1.08 firmware as well.

    this is good !!
    I didn't like battery data lose and auto land idea at all
    if power is low ok better auto land than a dead drop but not just because of data lose
     
  13. Knighthawk

    Joined:
    Dec 17, 2013
    Messages:
    60
    Likes Received:
    1
    A valid question, for sure. But, good luck getting an answer from them! ;)
     
  14. jadebox

    Joined:
    Nov 20, 2013
    Messages:
    490
    Likes Received:
    51
    Location:
    Oviedo, FL
    If communication with the transmitter is lost (i.e. "in fail safe mode"), then it will land if there are not enough GPS locks to return home. It's not going to land just because the number of GPS locks drops to 6.

    -- Roger
     
  15. LeoS

    Joined:
    Nov 25, 2013
    Messages:
    747
    Likes Received:
    1
    Their hardware and software has always been proprietary afaik, I don't see how this relate to them setting a seemingly over-conservative gps threshold.

    If you can appreciate the intricacies of phantom's design behind its apparent simplicity, I don't think you would underestimate their capability on this front.

    And thus, they put the wrong setting by picking 'less than 7' satellites, instead of less than... say 3? (absolute minimum to triangulate a position?)

    I believe this happens, although it ties in to development schedule, hardware\software revisions, etc (a bit too long to elaborate here)... but in this instance, really?

    Phantom III can return home with just FIVE satellite lock! Buy it today!
     
  16. jimre

    Joined:
    Nov 24, 2013
    Messages:
    371
    Likes Received:
    1
    Location:
    North Bend, WA
    The more satellites you have, the more error-checking you can do. Seems to me they chose 6 to ensure a reasonable margin of error. *Maybe* it could fly home (or in the general direction of home) with only 4-5 sats but with a greater chance of error (where error means random or uncontrolled fly-away). Sounds like a classic trade-off to me.
     
  17. jimre

    Joined:
    Nov 24, 2013
    Messages:
    371
    Likes Received:
    1
    Location:
    North Bend, WA
    Again, this is only an issue if you're already in Failsafe/Return to Home mode (something bad has happened) - AND it then loses the lock on 6 GPS satellites. Not quite worst-case scenario, but close.

    Perhaps the resulting behavior could be an advanced user preference:

    1) If you primarily fly in open fields or neighborhoods, you'd rather have the Phantom do an immediate controlled descent in this case (what it does now).

    2) Or if you're flying over water or something, then you'd rather risk the Phantom trying to fly home, with fewer satellites and a smaller margin of error, and greater likelihood of fly-away.
     
  18. LeoS

    Joined:
    Nov 25, 2013
    Messages:
    747
    Likes Received:
    1
    One more thing to do if you've lost control of the phantom (and it's not flying home):

    Run like hell toward it while flicking the ATTI switch and angling your transmitter/antenna to improve its direction :shock:
     
  19. iDrone

    Joined:
    Nov 14, 2013
    Messages:
    612
    Likes Received:
    2
    Location:
    Los Angeles, California USA
    +10 absolutely! Lol!

    One thing I learned performing range tests trying different antenna configurations is to restablish the Control link ASAP (you can watch the PV's beacons if you've also lost telemetry) it should come back under control when you get close enough. If the telemetry or video dropped out, I rotate the PV 90° once I get control so one of the antennas on the side of the camera faces me, then wait for a few seconds or exit & reopen the Vision app, then crab back sideways towards the LZ.

    iDrone