I am new to this board, and new to flying small scale equipment. I used to fly MQ-1's for the US Gov. Now I am working privately with Octocopters.
I have two air frames, one is a fully mission flyable Oktocopter with closed parts,
The other is work in progress using open source systems like the Ardupilot.
My question is are there any autopilots or control systems that will allow for the Octocopter to revert itself to a Hexcopter or even a Quad as an emergency recovery system should an engine fail?
This looks like tough nut to crack but I figure I would ask, if anyone knows if anything like this is in the works. Even it reverts to quad-system for the sake of a controlled crash, that would be better then the entire system spindling out control if an engine failed, resulting in a complete loss of A/C.
If there no such thing, than it would sound like a neat project to work once I dust off the ole engineering and relearn how PID control systems work.
Cheers
Replies
I believe that Octos, and to a lesser extent Hexas, are capable of flying with an engine out, without any fancy code, simply because of the way the PID stability code works.
I would like to know myself just how good the Hexas can do it, because losing one out of 6 motors obviously has a larger effect than 1 out of 8. But also because to balance properly, a hexa has to pretty much shut down another motor, so now it's down 2 out of 6, or a 33% reduction in thrust. An Octo with 2 motors down is only suffering 25% reduced thrust.
Now as far as any kind of code to detect a motor problem, I was looking into this a while back. I think it can be done by tracking the PID, particularly the I terms, for a pattern which indicates the craft is leaning to one side, while also having an unbalanced yaw which is being corrected by the stabilize Yaw I term.
Interesting idea, I guess my first question is how would you know a motor has failed ? except maybe a visual inspection by the pilot