Failsafe activated only when in flight

[GoogleCodeExporter]

I’ve had failsafe activate while I’ve had the quad armed and on the ground. 
Stupidly, I turned the tx off. The quad tried to take off but due to low 
batteries, was sluggish enough for me to catch it before it chewed my face off.
Could it be changed to only trigger failsafe when all current conditions are 
met AND there are changing values from the various accelerometers which would 
indicate it is in flight.

One concern to this idea is that the duration to determine if you’re actually 
airborne might cause enough of a loss of attitude to create an unrecoverable 
situation. 

Many thanks.

Original issue reported on code.google.com by crispin....@gmail.com on 31 May 2012 at 7:50

[GoogleCodeExporter]

I have a more robust solution prepped for next release, but you should not have 
triggered failsafe with current solution unless you were 10m form home 
position. 

Original comment by jasonshort on 1 Jun 2012 at 3:29

• Changed state: Accepted

[GoogleCodeExporter]

Thanks Jason,

You would be more than 10m from home quite often actually. My normal way of 
flying is turn it on, wait for lock, arm and take off. The problem is that the 
GPS is still pretty inaccurate at that point. So when I land in the exact same 
location as when I took off, it could well be quite a few meters away from me 
hence the "oh my dear soul, I need to enter fail safe" :)

Cheers,
Crispin

Original comment by crispin....@gmail.com on 1 Jun 2012 at 3:41

[GoogleCodeExporter]

I've added a new check that should prevent most issues. 
The copter now disarms after 25 seconds of inactivity. And It looks for full 
throttle before enabling failsafe. I gave up on the GPS since as you said it;s 
not as reliable.  You may power on at a table at the field and walk over to the 
helipad to fly. That could be 10m.
It's on the trunk.

Original comment by jasonshort on 1 Jun 2012 at 4:43

• Changed state: Fixed

[GoogleCodeExporter]

That's cool Jason, Will be sure to give some feedback when it's out.

Might I ask for an addition? Could there be a way to manually trigger failsafe. 
Say, another flight mode or a switch. Even if I have to edit the code and 
upload to test it.

Reason I ask is it would be nice to test failsafe without being so brutish i.e. 
turning off the tx. My tx (Spektrum) takes a 2-3 of seconds to boot and connect 
to rx. If things are going bad during a test, I have no hope of catching it.

Cheers,
Crispin

Original comment by crispin....@gmail.com on 1 Jun 2012 at 6:54

[GoogleCodeExporter]

Just use mixing on your radio to cut the throttle below 950.

Original comment by jasonshort on 1 Jun 2012 at 7:07

[GoogleCodeExporter]

Ha! Thanks. Never thought of that....

Original comment by crispin....@gmail.com on 1 Jun 2012 at 8:14

[GoogleCodeExporter]

Use arducopter version 2.8.1 Quad. Copter is at the ground without propellers. 
If I turn the transmitter off, the mode changes to "stabilize". After 20 sec " 
on "disarmed". The Motore go out. The mode "RTL" goes
  not on active. Have tried this out in the flight. The Copter increases slowly under strong wings up. What do I make wrong? TRH_FS_ACTION = 1. 
If I read the last contribution should switch the Copter to disarmed after 20 
seconds. Tested it like me without propellers have. It then falls down. 
Is this so good ? 
Remark: The text is translated with a translation program. Can one understand 
my question? 

Original comment by reinhard...@googlemail.com on 5 Nov 2012 at 6:55