Hello
I use my quadrocopter for FPV and fly over quite long distances. With my planes I can go up to 1,5km distance - with my Quattro I can only go about 400m. The problem is, when I get RC glitches, sometimes the controller does not accept any commands at all and the quattrocopter crashes.
On
http://www.youtube.com/watch?v=bs_DlI7hJ-U
you can typical scene from a flight with my FPV Wiicopter.
I get some glitches on the RC (at 0:22) - flight controller freeses and I could just see how the quattrocopter went down.
The right value with the percentage is the reciever RSSI, below ~40% I have glitches.
Sometimes I can recover from this, but it takes several seconds before I get the control back. Most times I lost hight, got even worse RC signal and lost control completely.
Does this behaviour come from the MultiWii controler, or is this coming from my reciever (corona 40MHz)? Shall I programm the reciever for failsave, or is this causing the proplem?
What is the reaction of the MultiWii controler on RC glitches?
Many thanks for your help and hints!
Peter
Failsafe behaviour?
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Alexinparis
- Posts: 1630
- Joined: Wed Jan 19, 2011 9:07 pm
Re: Failsafe behaviour?
Hi,
There is currently no failsafe implementation.
Multiwii reads 4 values of RC input signal and makes an average (moving average) of those values with a small hysteresis to limit the jitter.
If there is no more signal the last value is used and there is no timeout mechanism to replace it with a failsafe value.
But what happens generally with analogical RC: when it is out of control, the RX just send anarchical noise, and it's not easy to distinguish this noise form a valid signal. That's why it's hard to implement a good failsafe function.
There is currently no failsafe implementation.
Multiwii reads 4 values of RC input signal and makes an average (moving average) of those values with a small hysteresis to limit the jitter.
If there is no more signal the last value is used and there is no timeout mechanism to replace it with a failsafe value.
But what happens generally with analogical RC: when it is out of control, the RX just send anarchical noise, and it's not easy to distinguish this noise form a valid signal. That's why it's hard to implement a good failsafe function.
Re: Failsafe behaviour?
Hi Alex,
thank you for the info. So the problem lies in the failsafe of the reciever. I will reprogram it.
Without failsafe I expect to see some wobbling/jumping in the quattro's flight - should be better than just observing a crash without any influence from my RC.
I was just surprised, because my tricopter flies without problems to 800m distance - same reciever same 2m antenna. The only differences are the ESC's (Mystery on the Quattro and Plush on the Tri), the size (700mm motor distance on the Tri ans 400 on the Quattro) and the MultiWii software (1.6 on the Tri and 1.7pre on the Quattro).
Tanks for all!
Peter
thank you for the info. So the problem lies in the failsafe of the reciever. I will reprogram it.
Without failsafe I expect to see some wobbling/jumping in the quattro's flight - should be better than just observing a crash without any influence from my RC.
I was just surprised, because my tricopter flies without problems to 800m distance - same reciever same 2m antenna. The only differences are the ESC's (Mystery on the Quattro and Plush on the Tri), the size (700mm motor distance on the Tri ans 400 on the Quattro) and the MultiWii software (1.6 on the Tri and 1.7pre on the Quattro).
Tanks for all!
Peter
Re: Failsafe behaviour?
New Test results:
I tested the setup again and in 500m distance it fell out of the sky again
This time again I had no damage but in difference to last time the battery stayed connected.
What surprised me: The motors stood still but the green LED of the ardunio was on.
When I tried to restart the Quattro with the RC nothing hapend.
I decided to take the Quattro home in "on" mode and connect it to the PC.
But when I arrived at home the greed LED was off and I could start the quattro with my RC.
Did the MultiWii software hang for a while?!?
I am very thankfull for any help!
Regards
Peter
I tested the setup again and in 500m distance it fell out of the sky again
This time again I had no damage but in difference to last time the battery stayed connected.
What surprised me: The motors stood still but the green LED of the ardunio was on.
When I tried to restart the Quattro with the RC nothing hapend.
I decided to take the Quattro home in "on" mode and connect it to the PC.
But when I arrived at home the greed LED was off and I could start the quattro with my RC.
Did the MultiWii software hang for a while?!?
I am very thankfull for any help!
Regards
Peter