tkurtz

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Confusion setting up a failsafe
« on: February 14, 2016, 07:23:02 pm »
Hi,

I've read a couple good posts on failsafe modes but for the life of me I can't figure out how to set it up.

I'd basically like to have the failsafe shut off engines in the case of lost connection to the RC.

I have a 3 position switch that i use for 3 different flights modes and I read in another post that I could use that same switch but in a 4th mode which would be failsafe.

Can someone provide some advice on the set up to accomplish this please?

I'm thinking I need to somehow update the RC input window to give me 4 flight modes then in the Flight Mode Screen select a mode to allow engine shut down.

Am I making this too complicated??? :)

Thanks for any help/advice!

Todd

Re: Confusion setting up a failsafe
« Reply #1 on: February 15, 2016, 04:30:52 am »
I'm not really sure. A lot of people are using a switch to arm instead of down and yaw right or left. So motors can be disabled with the flick of a switch. And I was under the assumption fail safe is usually left to your radio and reciever. So that's setup on your radio. Maybe.  Mine is. I'm not sure about "fail safe" in Libre pilot. I've never used or set it up.
5" alien 4s 596grams with battery and GoPro FPV
Lantian LT210 4s 604grams with batt and GoPro FPV
GE X220 4s 6" 513grams with batt and HD cam FPV
Homemade acro X copter. 6" 4s - like a warpquad LOS

f5soh

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Re: Confusion setting up a failsafe
« Reply #2 on: February 15, 2016, 10:08:40 am »
There is two types of failsafe, the RC receiver failsafe and the onboard failsafe.

The onboard failsafe:
It monitor the input signal. If something wrong from wiring, failsafe values stored onboard are loaded. You can setup all inputs while the failsafe is enabled: Sticks (cut Throttle or low Throttle) and flightmode position (usually attitude)



The Rc failsafe:
You need to setup the Rc failsafe first, some receivers still output valid signal so the board cannot know if the radio link is lost or user smoke a cigarette.
Same as above, set all sticks and switches for failsafe state you want and store values in receiver. If receiver stop sending signal to board, the onboard failsafe is applied.

You need to test how your Rc receiver works when link is lost: remove props first !


tkurtz

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Re: Confusion setting up a failsafe
« Reply #3 on: February 15, 2016, 06:36:42 pm »
Ok, That worked brilliantly and exactly as I had hoped! Thank you!!! I went with the first option, on-board, as that seemed to cover me in more situations.

Thanks again!!!

Todd

f5soh

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Re: Confusion setting up a failsafe
« Reply #4 on: February 15, 2016, 06:46:23 pm »
I should set the receiver failsafe first :)

If your receiver keep the last command received and still output a valid signal, the board will never enter in failsafe mode...

tkurtz

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Re: Confusion setting up a failsafe
« Reply #5 on: February 16, 2016, 05:47:53 pm »
I think you're suggesting that I also set up a failsafe on my RC? Is that correct? If so, I'm not sure how to do that. I'd love to hear some suggestions. I'm using an Eachine i6 RC which I believe is a knock off or generic version of the Turnigy TGY-i6.

Thank you!!!

f5soh

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Re: Confusion setting up a failsafe
« Reply #6 on: February 16, 2016, 06:15:45 pm »

tkurtz

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Re: Confusion setting up a failsafe
« Reply #7 on: February 18, 2016, 09:47:07 pm »
Thank you for following up and providing the video to review.

So, in that video he is setting channels 3,5 & 6 to -100%. I can certainly copy that, but I would love to understand what it is actually doing?

I'd rather learn instead of just blindly copying someone elses work.

Thanks again!!!

Todd

Re: Confusion setting up a failsafe
« Reply #8 on: February 18, 2016, 10:22:04 pm »
In you radio. All the channels go from -100(low) 0(middle) 100(high). So channel 3 is usually throttle, so -100 means 0 throttle signal. If 5 is arm and 6 is idle or something they both shut off so automatic disarm and motors stop idling. So it basically kills the copter. And it crashes.  Which is preferable to personal injury or property damage. You set radio failsafe and FC fail safe seperately so if your radio loses connection your reciever won't keep going and if your reciever dies your flight controller won't keep going.  It covers all your bases and makes sure the copter won't fly away if your Tx/RX lose connection or RX and flight controller lose connection. It just shuts down instead. 

I think that's right. No my head it is at least lol
« Last Edit: February 18, 2016, 10:25:45 pm by NicholasDavid »
5" alien 4s 596grams with battery and GoPro FPV
Lantian LT210 4s 604grams with batt and GoPro FPV
GE X220 4s 6" 513grams with batt and HD cam FPV
Homemade acro X copter. 6" 4s - like a warpquad LOS

tkurtz

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Re: Confusion setting up a failsafe
« Reply #9 on: February 18, 2016, 10:51:48 pm »
Interesting...

If I'm interpreting this correctly, when you set up a Tx/Rx failsafe when you power on your both your Tx & Rx they create a sort of handshake. If that handshake is broken due to Tx power failure or Rx flown out of signal distance the Rx will trip failsafe and take whatever channel you set to -100 and go low on it.

Example to confirm learning is complete: Assume Channel 3 is throttle and Rx has flown out of signal range...
1) If Tx failsafe set at Channel 3 -100 then: motors to stop, fall from sky
2) If Tx failsafe set at Channel 3 0 then: motors to 50%
3) If Tx failsafe set at Channel 3 100 then: motors to full and attempt earth orbit

Do I have it?

Re: Confusion setting up a failsafe
« Reply #10 on: February 19, 2016, 02:47:21 am »
Yes correct,but, and I think I see where you are going with this, you do not want to set it at -90 for a sort of floaty or controlled descent. You want shutdown (unless it's a crazy expensive camera rig or something. Then that's your choice) but say it went to fail safe and you had it set for 10% throttle that would be about -90-80 for that controlled floaty crash instead of meteor mode. But you got stuck in a tree on the way down.  Then your motors and esc's are trying to turn at that controlled descent setting and they can't so they are all going to burn up. Or it flips upside down when it "crashes softly" 4 smoked esc's and most likely the corresponding motor as well.  Probably Better just go shutdown.
On some radios you can set a delay before it goes failsafe. And this I do recommend. Set a 3-5 second delay before fail safe kicks in so it waits a few seconds to see if you regain signal. So it will hold the last command you gave it (ex:forward flight) to see if it reconnects before it tumbles from the sky.

Zero throttle
Zero aileron
Zero rudder
Zero elevator or all at -100 in your radio for failsafe
5" alien 4s 596grams with battery and GoPro FPV
Lantian LT210 4s 604grams with batt and GoPro FPV
GE X220 4s 6" 513grams with batt and HD cam FPV
Homemade acro X copter. 6" 4s - like a warpquad LOS