Multi-rotor arm construction

[Supergoldfish]

How does flex in arms effect multi-rotors? I was thinking of using carbon arrow shafts to build a tri. But now that I have the arms mounted to the frame I see that the arrow shafts flex slightly. I was thinking that maybe this will help reduce vibrations to the frame / cam? Or will this just cause great instability?

Any insights?

 

[glydr]

Rigid = better. Take the vibe reduction methods to your cam holder.

 

[colorex]

+1. You can fly with flexible arms, but it can get bouncey

 

[Cyberdactyl]

On the serious side, boom flex is something to consider. Especially when putting cameras, and most especially very small cameras, on board.

Since boom flexing (vibration) cannot be completely removed, different materials can effect what mechanical frequency gets transferred to the gyros, accelerometers and cameras on the central hub from improperly or poorly balanced propellers and/or motors. Wood is a wonderful and inexpensive dampener of the higher frequencies. While I have yet to build with aluminum tubing, square or round, . .I would suspect it transfers a fair amount of higher frequencies that wood would dampen to a great degree. Plastic, glass fiber and carbon fiber probably fall somewhere in between.

So far from my experience, it is MUCH more difficult eliminating "jello" from ultra small cameras such as the 808 #11 or #16 as compared to a GoPro or similar. The smaller camera simply doesn't have the resistance from mass inertia to assist in dampening the higher mechanical frequencies.

 

[Supergoldfish]

Well I tried the carbon arrow shafts for arms. It was a fail. They torqued (twisted) way too much, and made the yaw compensation bananas. The flexyness probably didn't help either.. Went to the old faithful wood and we are smooth as silk.

Stiff is indeed better.