Been testing a brushless gimbal on my quad, it's an own-design laser-cut Liteply gimbal which uses a Foxtech AIO (Martinez) controller ($50) and Foxtech 2208-70kv motors ($21). Information is a little hard to find on the controller and tuning of these things a little tricky but so far the results have been very encouraging.
The gimbal was laser cut from 2.5mm Liteply but needed some reinforcement to prevent flex so this is now version 3.1 :)
3mm or 4mm might be a little better in the stiffness dept. but this is not bad at all. It's also really light at less than 35g for the ply parts!
Camera is one of the new 1080p Mobius Camera's which is pretty amazing for the price of $70. just the colours are a bit saturated but that will be sorted out with later firmwares.
A very short video flying above my Johannesburg suburb showing the fantastic stabilization (Note: this is only 720p and I tried to keep the upload size small with a low bitrate, Youtube also takes some of the quality away):
Comments
@ george: this is a completely different way of stabilizing a camera, probably 100x smoother than the best servo. The brushless motors used here are completely step-less whereas ANY servo is stepped (1024 steps for full rotation I think). It's chalk-and-cheeze, a servo powered gimbal's video is mediocre at best.
That's why they have their own special controller, this is a revolution in stabilization, previously only available in gimbals like the Zenmuse at $3000+ (http://wiki.dji-innovations.com/en/index.php/Zenmuse_Z15)
This is the silicone wire I use for my IMU cable, and I've also split 2 strands off and use them as a nice light and flexible gopro cable.
http://www.goodluckbuy.com/4p-silicone-wire-28awg-data-cable-brushl...
@Wesley, change the wires for some really soft ones, I used the cable from a set of stereo earphones plus one other wire, all really soft. The stiff wires that came with the controller are unsuitable IMHO. Balance of the camera of course, must be pretty perfect too.
@Mark, didn't even know such small sliprings were available, thanks. Would add a bit of expense and weight though. With soft wires mine seems to work fine.
@Daniel, not using any dampening. Props are well balanced though and the camera is mounted on Velcro, there's also Velcro between the base plate and the mount that connects to the quad which might damp the system slightly.
Wesley, Sandton CBD actually. Yes I've had the same issues, it's a fine balance to get the PID's and PWM sorted, higher PWM holds firmer but you can get vibrations (I'm using around 40), my P's are quite low (5-6) and I's quite high (40-60), D's = 20-40.
Soft silicone IMU wires help a great deal and are almost mandatory IMHO. If the gimbal gets pushed over too far it sometimes goes crazy taking a while to settle. Also can take long to level then, much longer than normal stabilization but it sorts itself out. Must run on 12V (3S) at least I think, to get enough power for the motors.
@Megaflare, I'm not flying FPV just line of sight in that video, currently there are no transmitter controls connected to the gimbal but you can add roll and tilt. The plans aren't available but I might publish them at a later stage. For a GoPro a fair bit of fettling would be needed to the plans because as with all brushless gimbals the camera must balance exactly, this was designed specifically for a camera the size of the Mobius
$50 for controller, $42 for motors, $5 for laser cutting, $10 for Liteply, $5 for Cyano, $70 for camera.
So $182 for everything, as I said, cheap-ish :) Not $3000 Zenmuse expensive.
Strength-wise this would be able to carry a GoPro and if one used 4mm ply you could put a small digicam on it, although it would have to be scaled for anything larger as it won't balance.