Vtail Octocopter

Mathew Wellington July 30, 2011 at 8:10pm

i see my first post is mis leading - ment to say "i need to use APM now" not that I am using APM on it currently, hence need some help with the mixing setup

Mathew Wellington July 30, 2011 at 8:04pm

the picture is wrong, left rear motor is CW , not CCW

the rear motors are around that way so the prop tourque adds to the thrust in the direction you want to go

Mathew Wellington July 30, 2011 at 8:02pm

thanks guys

I built it 70mm wide and 800 long (motor to motor)

motors - RCtimer 750 kv with 10 by 4.5 props

battery 4S 5000 to 12000

the most i have lifted is 3.8kg, i plan it to go to 5, you dont want to go much over that, as in a decent side wind you need alot of reserve thrust

Mix

this is from Copter Control settings, with 127=100%

http://forums.openpilot.org/topic/5689-vtail-octo/

hope the above makes sense, but essentially its as follows

front motors , pitch only, 50% authority

rear motors pitch at 50% and Yaw at 50%

side motors roll only 50%

no need to control individually, and would much rather save the channels, i see no need for it

the hex uses an identical mix/channel count, except the roll needs to be cranked up to 75% authority (maybe even more after todays testing) to compensate for only one motor each side

If you guys are able to do this mix on ACM2 i would be very apreciative

Camera - just need roll comp, pitch comp and pitch mixing with TX input, didnt know it was enabled yet in ACM 2

Been flying the Vtail hexa today, its nice as its a less imposing machine to deal with, smaller and lighter.

But the Vtail 8 is much more stable, the paired roll motors work well and stop any induced yaw when flying sideways ( the hex has induced yaw)

Also check out the VTQ (Vtail Quad) - awesome for FPV and stunt flying, as its CG is closer to the front, it pivots around the front motors nicely https://www.youtube.com/watch?v=vA8MPgPpHI0

Developer

Jason Short July 30, 2011 at 6:16pm

Thats really cool looking. I'd be glad to help. Just answer Max's questions above. Also, I would change to 8 independent controls rather than 5.

Camera mixing - what's your goal? Both pitch and roll outputs are fully stabilized already. By default channel 6 mixes pitch. Roll could easily be mixed as well.

Coptaire July 30, 2011 at 2:36pm

Did you lift 6 kilogram with it ??? like a pack of 6 mineral water bottles ???

You display an incredible 2.5 : 1 thrust to weight ratio.

Could you describe all the mounted gear in detail?

(I like the tri hexa with v-tail, too)

Mark Pepping July 30, 2011 at 2:34pm

Looks absolutely awesome! Well done.

nubli hashim July 30, 2011 at 1:38pm

nice idea, and more important it works. splendid