What can cause disarming?

[jim lee]

One of my guys has a weird issue where his quad will randomly disarm in flight. We're pretty sure its disarming 'cause one time he was able to rearm it before it crashed. Sometimes he can run out an entire charge with no issues, sometimes it just falls out of the sky. We even caught it on video where it was flying along all happy and just shut off.

So what can cause a disarm? Will loss of radio signal cause it? Anything else?

Thanks!

-jim lee

[waltr]

Is MW setup to arm/disarm with stick commands?
Is so is he getting the sticks in the Disarm position?
Stick disarm is Minimum Yaw and Minimum Throttle (values less than MINCHECK) so this could happen if the receiver signal is lost, the RX does not have Fail Safe mode and the RX outputs go away or just decrease in pulse width to go below the MINCHECK value. This would be highly dependent on the RC radio RX you are using.
I've not seen this but have Fail Safe enabled in the MW code. I highly recommend enabling Fail Safe in MW and carefully checking that it works properly with the copter tied down. This is when you also ensure the FS throttle value will allow the copter to descend.

[jim lee]

Thanks for the reply!!

Yes, its set to the stick arm/disarm. No, he's not hitting the disarm, he's pretty experienced. In fact, if he's high enough, he's been rearming in the air to save his machine.

Looks like I'm going to need to look into the failsafe stuff and reconfigure accordingly.

Thanks again, I really appreciate it!

-jim lee

[mike105105]

Could be a brownout issue. Make sure all of your power connections are good, battery isn't drooping too much, and BEC powering the FC is working right.


Mike

[jim lee]

We have everything in stock. So, we started replacing one thing at a time. Radio, ESC unit, MulitiWii control board, battery, wiring.. The last thing we swapped out was.. The Serial GPS unit. That was seriously the last part of the original machine. Seems to have solved the problem. How the GPS could cause this is a complete mystery to us. This is why it was the last piece, we figured there was no way it could cause a problem.

Not positive, but it flew today without issue. Tomorrow we'll burn some batteries and see how it holds up.

-jim lee