Long story short, I'm in the field trying to gather imagery with my hexacopter and I broke one of my motors. I can't ship a new motor out before the field season ends, do you think the hexacopter will compensate and still fly with only 5 motors? Or what if I took off one additional motor, and effectively made it a quadcopter?
thanks
Replies
Depends on how much redundant power you have. I can fly my hex with 5 motors with no problem, even it don´t need to yaw (which is kinda black magic to me :D because it must yaw to stay level). But when i force it to yaw, it becomes way way more stable and it´s capable to lift even ~15-20% more. And with bigger props (12x3.8) it is even more better.
No.
A hex will not fly well with one motor missing. You end up with a horrible pitch-yaw or roll-yaw coupling. You may be able to do an emergency landing, but it would be very difficult to fly.
I have flown my Octo with 1, and even 2 motors disabled. I've even lifted off with 3 motors disabled, but that was really a stretch. To achieve true redundancy, you need an Octo at the least, better yet would be a decacopter.
There are many stories about beeing able to land a hexa when a motor or prop was busted while flying. I tried once myself, having a prop break off and flying with half a prop. I was able to set it down in a field without much damage. But fly it like that? No way, not in my case.
But, that's ust my case. I had quite low power motors and small props, my rig did not have any redundant power at all.
Having more powerful motors and props might make it work.
The controller (APM?) should compensate but I don't think anyone can say "yes" or "no" without knowing your motors, props, controller, rig AUW, intended flying modes and so on. Even then, they would be educated guesses.
Apart from 17% loss of raw lift power, Yaw would probably be the biggest concern, with one of three propellers in that direction gone, you would have a hard time compensating for yaw drift. The remaining two motors would each have to spin 33% faster, making the max power cieling come down another 33%? I'm just thinking out loud here. :)
All in all: it is very plausible but the only way to know is to test it. I would use stabilize mode and try to hover... and take it from there.
Good luck, let us know. :)
BTW, is there not a local shop with a motor that is similar enough? Something with roughly the same kv should be better than nothing?
KR
Magnus, Sweden