Naza DX8/AR8000 Failsafe RTH

[ChrisH]

I';ve read conflicting information about the position of the throttle stick when setting the RX/Naza RTH (fail safe) function if signal is lost. Several guides say throttle around 50% but the DX8 manual seems to indicate 0%. Does it matter as the control for the RTH is managed by the Naza and only triggered by the RX? I tried to set stick to 50% but TX howled at me and refused to do anything until stick was at 0%!

The function indicates correctly in the assistant, i.e., status changes to RTH when TX turned off and back to normal when TX back on. I just don';t like the idea if the throttle is bound to 0% when it goes out of range and turns into a brick cos of 0% throttle!

You experienced guys have a view on this please? I';m trying to apply belt, braces and several packs of elastoplasts before my first flight!

Thanks. (Hope this isn';t a stupid question!) 

[Jumpy07]

Its not a silly question..  I asked the same one last week..

You are right.. Naza guide says more than 10% throttle.. for failsafe.. not sure why..  but may stop the Naza arming and failsafe';ing by mistake when you switch on RX before TX.... or just to stop it failing out of the sky until it figures out what to do..


I set my FrSky up this way.. also set a channel safety switch to trigger failsafe when I wanted..

PS: When it triggers failsafe you have to toggle the GPS/A/M switch to regain control.. as I found out the scary way.

[ChrisH]

Its not a silly question..  I asked the same one last week..

Not just me then!

I';ll see if I get any more replies with a positive one way or the other. Difficult to bind RX/TX when TX won';t turn on correctly because throttle not at 0%! When I';m confident enough and the standard RTH works OK I may risk turning TX off at VERY low altitude in case it does drop!

I had seen the switch toggle to regain control trick! Also got a switch to invoke RTH without switching off TX!.

Thanks,

[Balders]

I setup Dx8 failsafe and have also done my Dx6i failsafe without any issues APART FROM!

Setting switch positions.  The switch I wanted to trigger failsafe (ie in a test situation) just would allow me to set when the Tx turned on/bind/failsafe mode.  Was tearing my hair out for ages on that one, until I figured out that if I set another switch to perform the same function, do the bind/failsafe, then afterwards set the switch function back to the switch I wanted, worked like a charm.

I seem to recall ignoring the throttle to be honest.  I think the advice is, if triggering failsafe, don';t then drop the throttle and then try to come OUT of failsafe, as if you get control back with low throttle, it';ll fall out the sky.

Failsafe is purely set on naza by switch position so the throttle really shouldn';t matter.

[ChrisH]

Thanks Balders,

You backed up what I have managed to assume from various sources. Maybe with different TX/RX combos the sequence and settings may be different. Just hope that assuming here is not a problem! Will post an update when I have proved it or ordered a load of new props and arms... 

[Jumpy07]

Been doing a bit more digging on this..
Seems the throttle is recommend greater than 40% to stop it falling out of the sky when coming back from failsafe..   kinda makes sense

[Balders]

put it this way, plug it in to naza assistant. Turn off your transmitter.  If the slider moves into failsafe, it';ll work, regardless of whatever your Tx is up to, because IT';s TURNED OFF



It';s the turning back on where it becomes more critical, to get it out of failsafe mode, you have to toggle the flight mode switch between manual and GPS I think (and obviously if you';ve used a switch to invoke it, make sure the switch is off again).

It all just makes sense, first time you use it.  It';s a beautiful thing to behold.  Just make sure you had a good sat lock before you took off :)

[SimonS]

I had lots of problems trying to get the DX8 / Naza RTH to work correctly and finally managed it. Here';s how.

First, Remove the props from the motors. Then set the GPS/ATT/MAN switch to GPS/ATT/RTH in the Naza software by adjusting the servo travel on the DX8 .

Next go into the DX8 and find a menu that says ALARMS or something similar (can';t remember the exact wording) and turn off the alarm for throttle position.

Turn off the DX8 Tx.  Plug the bind plug into the Rx and power it up then remove the bind plug.  Now set the DX8 throttle to 50% ish and the GPS/ATT/RTH switch to RTH then hold the Bind button and Power up the DX8. When the display shows BINDING you can release the button.

When the binding is complete set the switch to GPS and turn off then on the DX8. Power up the motors and set the throttle to about 20% (enough to keep the motors running). Now watch the Naza software while you turn off the DX8.  the GPS/ATT/RTH slider should go to RTH and after three seconds you should here the motors increase power as the quad tries to climb.

The step that no one tells you about is turning off the alarm.  If it is not turned off the tx is inhibited above 0% throttle and the system will not bind.

[sausageroll]

When you bind in preset failsafe mode (as mentioned above, power up RX with bind plug plugged in, then remove it and bind as normal) the system will remember all switch positions. I set my thorttle to 50 percent so it hovers, and the mode switch into fail. I guess you could put your throttle to zero but I wouldn';t as it would probably jump to zero before the fialsafe took over, and thats a bad idea.

Remember though, if you add a feature like retracting landing gear, re do this so the legs deploy when it failsafes. I also set it so the camera tilts up, if it lands when the cmaera is down the lens will go right on the ground, so when it goes into failsafe it automatically flaps the lens up out of the way.

Its pretty clever really.

[shaktar]

I did not need to turn the Alarm off on my DX8, I just quickly flicked it down and then back to above 40%. Worked fine.

I have the F mode 3 position switch for my  GPS/ATT/MAN and then the gear switch overrides it to fail-safe no matter what its on. So I bound it with that on when the TX goes off or louses signal.

[ChrisH]

Tested my RTH over the last couple of flights. Worked fine on switch and today tested the Tx off RTH - worked perfectly I';m glad to say!

The RTH bind was done with throttle on zero as the Tx/Rx would not bind with stick anywhere else. It showed up as working on the assistant OK and today proved it. No dropping or other odd behavior, just a climb then it came home. Phew.  ::)

[eyeflying]

The RTH bind was done with throttle on zero as the Tx/Rx would not bind with stick anywhere else. It showed up as working on the assistant OK and today proved it. No dropping or other odd behavior, just a climb then it came home. Phew.  ::)

I can confirm that setting the throttle to zero is fine when setting the failsafe on the Naza. I have a Spektrum DX8 and this method works with Spektrum Rx and the Orange 7 Channel receivers.

[VinHex]

I';ve just helped my friend build his Disco..  Set his throttle to 25% in failsafe.. He switched it today and all worked great.  Does make me cringe when the button is hit but so cool when it lands back at your feet..

[billmac]

Hi
I used this settings and they work fine DJI Naza Flight Control v1.6 How-to for DJI FlameWheel Multicopter 330,450,550

[ChrisH]

I used that West Coast video to set the switches. Very useful! That side worked well, it was the tx/rx preset bind that caused the mixed messages. The DX8 manual does not insist on 50% throttle unlike some others it would seem. It worked which was the main thing. A great confidence booster in early flights!