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Aperhinsive about the RTH

Discussion in 'General Discussion' started by mtsoule, Jul 30, 2014.

  1. mtsoule

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    ok, obviously I am a newbee, had my P2V for about a week now and flown about 10 times, all great experiences! still learning to fly, the highest I have gone is about 300feet (not really sure where that sits in the full range, am I nearing the end or just barley out there) slowly going more and more. before I get to the point where the RTH kicks in, I want to make sure I fully understand it and have everything where it should be. as I am sure most of you experience the first time you turned the transmitter off, or lost connection with the unit, all you can do is pray everything is doing what its supposed to.

    my power up procedure is as follows, (not sure it makes much difference except for turning the transmitter on before the P2V)
    1. Transmitter
    2. WIFI booster
    3. P2V
    4. iPhone

    I do this because, (I have a dedicated iphone for the unit, no sim card) by the time the iphone connects to the wifi and I start the app and get it going, the P2V has acquired the GPS.

    before I take off, I always look at my distance and make sure that it is 0 or really close to it, so I know it has acquired its home location.

    am I just paranoid?
     
  2. ProfessorStein

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    If RTH is activated organically (ie - the Phantom truly goes out of range) you should actually be able to regain control once it returns to within range. Check the user manual for instructions to do this.

    It's a little trickier if you're just testing by turning the RC off. Sometimes everything rebinds when you turn the controller back on, and sometimes it doesn't... so you're a little bit at the will of the Gods.

    But, again, if it's a true RTH situation, you should be good. So don't let that paranoia get to you.

    In start up, keep an eye on the LEDs. They should go from slow flashing orange to slow flashing green when a GPS lock is acquired... and then there's a very brief stint of fast flashing green when the home point is locked in. Once you see that, you should be good to go. Obviously the more satellites it's locked onto, the more accurate the home point will be.

    I've never really paid attention to the distance read-out at start up, so I can't say for sure, but my hunch is that's always going to say 0 after a power cycle and before the motors are moving... so I'm not sure that's an accurate check.

    Best to pay attention to the LEDs. RTM for more info.
     
  3. Meta4

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    Re: Aprehensive about the RTH

    Don't wait for RTH to happen someday when you are not prepared.
    Try it out so you know how it all works under controlled conditions.
    In a clear open area, send your machine up 50 feet and 100 feet out - turn off the RC and watch RTH at work.
    You'll see your Phantom come back and start to descend slowly.
    You can switch on and take control again or watch it do a complete auto-land and shut down.
     
  4. kydan

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    You are better off by *not* turning off the transmitter (commonly referred to as the TX) to see if RTH works. It would be wiser to assign the failsafe switch on the right side of the TX to RTH in the NAZA software. In doing so, when you need a RTH function, once it comes back you can flip it back to GPS or manual mode and take control of it before it auto lands. If you turn the TX off, you are at the mercy of the GPS and if it's not correct you will experience a fly-away.

    Always make visual confirmation when you plug your battery in that it marks its home location and do not take off in GPS mode if you don't have all the required 7+ satellites.
     
  5. kydan

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    Re: Aprehensive about the RTH

    Follow my advice in the post above. It's not a good idea to switch off the TX aka transmitter (which I guess is what RC is referring to). It's not guaranteed to bind to the quad when you turn it back on.
     
  6. BobUnplugged

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    I have never "tested" RTH. If it works, it works, and if it doesn't work, then you have just INDUCED a problem for no good reason.

    A few days ago, I lost control signal at about 2000 feet, and it came home. When it got fairly close, I flipped the S1 switch down one click and then back up, and regained control.

    RTH WILL WORK if you have properly locked in a home position. Rather than testing RTH, may I suggest a better exercise is MAKING SURE that getting a GPS home position is an unbroken habit.

    And if you want to double-check that you have a home position, you can (even while in the air) flip the S2 switch down one click and back up five times real fast. You'll see the green lights on the rear legs flicker, and THAT is now your home position.
     
  7. mtsoule

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    Absolutly!! I never take off until I see fast green flashes followed by have slow green flash, then I wait about 20 seconds to ensure I have a good home position.

    I agree that turning the TX off is probably not a good idea, just didn't know how else test it. and maybe the word "test" is not the right word, I just want to be able to recognize it and know its happening when it does. much the same way that when I was learning to drive, dad flattened one of the tires and me drive on it so I would know what it felt like and how to change a tire. apologize if its a poor analogy.

    as far as the NAZA software goes, I haven't even installed it yet, currently running out of the box and in nothing but GPS mode. today will mark one week of flying my P2V

    I don't want to mess too much with S1 or S2 until I fully understand what they do, but I did do a good compass calibration.... well eventually I did, lol
     
  8. BlackTracer

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    IMO you should "test" RTH, or more in the vein of this discussion, familiarize yourself in practice with what happens when it is activated. Like the others have said, so you know what to expect. I think there is a step in the pilot training manual that has you test it. It looks like you know how and when you get a home position and are flying with GPS. Fly out to 100 ft out and less than 60 feet up and just turn off the transmitter and watch what happens. Pay attention to the vision app, and the aircraft movements and LEDs. It is totally safe to test this. I did on my very first flight. I think you would be more afraid if it happened unintentionally and you were seeing it for the first time in an "emergency" situation, not knowing what to expect and how to deal with it calmly.

    Funny thing I had not had an RTH since my first flight in March, but then have had 2 in the last 2 days. One was initiated from the new low battery question and answer, the other an RTH after the last waypoint was reached in a GS mission. Both worked flawlessly. Note however that I regained control above the home point before it started to come down because I like to land it myself thank you very much.
     
  9. ProfessorStein

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    You also probably don't test your smoke detector or test your brakes when you get in your car... you just wait and hope they work when you need them, don't you... with no context of what they'll do should they be activated.

    There IS a good, valid reason for testing RTH: to experience what it actually does, how it behaves, just how far up IS 60ft/20m, what indication you'll see on the LEDs and when, as well as how to recover... so that when you're in a panic when your Phantom is suddenly not responding to your controls, you can recognize all this behavior and know what to do.

    I've tested RTH once all the way to the ground (to see how well it lands and how accurate it's landing spot was) as well as a couple times just into recovery (to make sure I knew how to get out of it).

    But I wholeheartedly agree that turning off the RC is NOT the way to do said testing (I do believe I mentioned that).
     
  10. mtsoule

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    I agree that it should be tested and I will test it!! however I am not sure how to test with out turning off the RC. I do agree that turning off the RC does not should like a good idea, although the manual say to do it. I would much rather have a switch that does it.

    but as I mentioned, I have not installed the NAZA software, perhaps I should do that.

    one last question, I had heard or read, that the P2V will not let you fly farther or higher than it has battery to RTH, is there any truth to this?
     
  11. Happyflyer

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    I have had a RTH recently when P2V went behind a water tower. It was over the 20M height so it started to come back to me. Gained control without problem. One thing if/when you switch to NAZA mode I check every time I take off. I move quad about 75 to 100 feet away from me, point it in my direction, flip the S2 switch to HL, pull the right lever down and see if it comes back to me. That way I KNOW it has the home position locked. Checking lights in the bright sunshine is not that easy to do IMO.
    UPDATE: Also be sure you get a GPS tracker for your quad.
     
  12. BlackTracer

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    I also noticed the little H symbol on the GS page. I wonder how reliable it is in identifying if your home point is established. I also do the "fly away, come back in HL" trick to verify the home point.
     
  13. ProfessorStein

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    There really is no "loading" of the NAZA software. In fact, your bird is already flying with NAZA. It's how the Phantom does what it does. All you're missing is the ability to CONTROL the NAZA functions and settings (Vision mode simply hides all that from you... dumbing down the interface, rather than the underlying functionality).

    All that's needed to get your bird into "NAZA mode" (and have control over the settings) is to go into the Assistant utility and select NAZA. Then you have the ability to configure the switches.

    And, in fact, with both switches up, you are, in affect, in Vision mode. No difference at all between that and where you are now... other than the ability to switch on other functions... like RTH manually, etc.
     
  14. ProfessorStein

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    Sometimes it rebinds, no problem... and sometimes it does not.
    Just because it's always worked for you doesn't guarantee that it always will.
     
  15. mtsoule

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    one last question, I had heard or read, that the P2V will not let you fly farther or higher than it has battery to RTH, is there any truth to this?
     
  16. ProfessorStein

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    The new update supposedly keeps track of how long it will (theoretically) take to return to the home point, and will initiate RTH once it determines that it's close to the point of no return (or 30% battery life, in most cases). So you're kind of correct.

    But you have to be running the latest firmware (3.0.6). And even then you can override if you wish.

    And dirkclod, there IS a way to initiate RTH manually (via a position on S1), but you have to set your Phantom up that way to be able to do so. That is truly the "safer" way to RTH, rather than switching off the RC.
     
  17. ProfessorStein

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    Yes... but like I said in that thread... I don't remember having the option of setting RTH on Switch 1 while I was in Phantom mode. Pretty sure I had to switch to NAZA to gain that ability (at least with my P2V). But that could just be my bad memory... it's been quite a while since I made the switch.
     
  18. srandall25

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    I actually used the manual failsafe S1 switch in NAZA mode to initiate RTH... when I did, it said 'lost control signal' and 'coming home'... this made me believe that the manual S1 switch to failsafe was functionally equivalent to turning the controller off... meaning, if it truly caused a loss of control signal by switching S1 to failsafe, well that's exactly what is happening when you turn off the controller... so I'm not quite sure what the difference would be since in either case, the controller must still re-bind at a later point in order to regain control... someone please correct me if i'm wrong here...
     
  19. kydan

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    Flipping the S1 switch to failsafe and turning off your controller both initiate RTH.

    The difference is the S1 switch keeps the controller turned on so it doesn't lose its binding. When the drone returns to a position where you are ready to takeover (or you can just let it fully RTH and land if you wish), you flip the S1 switch back to GPS or ATTI and begin flying again.

    If you turn the controller off, you will more than likely be unable to regain control of the drone by turning it on. Instead, you are at the mercy of where the drone is going for its RTH location. If it's wrong--you are out of luck and have a fly-away.

    The smartest approach is to utilize the S1 as the failsafe and use that for RTH. I hope that helps.

    Edit: When I say "binding" I really mean the "link" between the TX and the Quad. We haven't had to bind the Phantom TX because they are already set that way out of the box.
     
  20. srandall25

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    My argument is that flipping S1 to fail safe breaks the bind between the controller and the phantom. The proof is that when you flip it, the message "loss of signal" occurs. If DJI's way of implementing the manual S1 to fail safe feature is to simply break the control signal, then there is no bind between controller and phantom in either case. Also, to say you will more than likely be unable to regain control of the drone by turning on the controller is not true. There are many in this forum who use this method routinely with no problems.