3d printed folding phantom-killer

[SuperSharpShooter]

I've just finished the build of a small folding copter to travel with, which holds a gopro on a 3 axis gimbal, or a Canon S110 on a 2 axis gimbal. It's wider than it is long, and is about 460mm diagonally.

it weighs 1.7kg fully loaded with 5k mah 4s battery, FPV gear, gopro gimbal, and is running sunnysky x3108s 720kv motors with APC 10x4.5 props. Flight time is about 15 minutes. I've made the central plates both from 2mm FG plate, but this is unnecessarily heavy, so I will change the top plate for one made from 1mm CF.

I started with Angel's monoblock design, but then scaled the arm blocks down to fit 12mm arms. I modified the ESC32 brackets so that they could be stacked, and I also made some holes in them to stop heat buildup. I created brackets underneath these to hold both the receiver and the VTx. The legs weigh 8g each and just clip on tightly, so can be quickly removed for folding. They can also be zip tied on for a more permanent fit.

So far it's pretty much everything I've always wanted from a small copter. Super stable video with high precision control (thanks Autoquad), long enough flight times, clean video feed, and packs down into quite a small package for transport after removing four m3 bolts on the arms. The front and rear arms both fold back to all be together.

I'm not much of a designer, so it could be made to be prettier, but I'm happy with how it's turned out considering this is the first thing I've designed! Just need to figure out a way to run all the cables from the gimbal in a tidier way without restricting the movement.

[aBUGSworstnightmare]

Hi Glenn,

Well done! A 3D printer is something I'm thinking oft too.
Joerg

[kinderkram]

Very cool, Glenn.

Yah, the Spaghetti is always something to fight with - or hide it. Maybe your printer can do some cap that fits the GPS shield?

btw: how do you fold it?

[SuperSharpShooter]

[chschmid]

Congrats Glen, nice machine. I usually pack the wires in heatshrink or some "fabric tube".

[kinderkram]

Burning Man, huh?
Have a nice time there, Glenn and bring some nice shots of the event.

Desert dust is a natural enemy for motors - some compressed air treatment before and after take-off might be a good idea.

[SuperSharpShooter]

Yeah BM is always a good time! I took a tricopter there a couple of years back. A bit of compressed air seemed to do the trick, and the same motors I was using then are still running fine now. I'll probably end up hand launching to keep things a little more dust-free this time! It's not just dust, but corrosive alkali dust...

[afernan]

Very cool Glenn!
I'd like to see some more images and vídeos. Pls, post some

[SuperSharpShooter]

Just shot two music festivals with this (Bass Coast and Shambhala) and it's been performing well and I managed to safely capture some great footage. There were 4 or 5 other people flying phantoms there, some quite irresponsibly... There was one which ended up flying away, and I was told another crashed into a stage after flying low over a crowd. Wouldn't be surprised if they ban them next year.

There are only a couple of things that are really annoying me: The lack of baro-only altitude hold, as I find it very hard to hold a precise altitude in manual mode when flying beneath a tree canopy without 3d lock, as the copter will behave unpredictably when it gains a 3d lock. Also the ticking twitch which sometimes occurs when taking off with a 2d GPS lock, and gaining a 3d lock once in the air. This has caused a crash on my hexa when taking off in manual mode before, and I've had the same symptom but without a crash on this quad a couple of times

Flying out to Reno for Burning Man in the morning. Hope it goes ok, sounds like it's very dusty, and there have been high winds most afternoons (and some reported tornadoes!)

[JussiH]

Hello Glenn.

Looking forward to seeing the footage. Thanks for representing AQ in a safe and responsible manor.

At the moment, the only way to get a clean altitude hold based on baro only is to disconnect the GPS antenna, but that is hardly practical, I know. But if you have DIMU, the Baro only altitude hold is very stable without GPS and it is a crude way of acheiving what you want.

We have discussed doing a baro only mode a while back, but we never got around to it. At the moment the whole team is working hard on the next big release and documentation update, but we will put it back on the agenda after that.

In any case, taking off without a 3D lock and then gaining it in the air while in position hold mode can lead to unpredictable and twitching behavior as the GPS kicks into the UKF and begins correcting heading, velocity and altitude estimates.

If you take off without 3D lock, you should always wait for GPS lock to appear, then fly some straight lines in manual mode to allow the UKF to converge the velocity and heading estimates based on the GPS, before attempting a position hold or DVH maneuvers.

If a solid 3D lock and PH is gained before GPS signal is lost, you should not see unpredictable behavior when the signal is regained unless the IMU calibration (and specially the AIMU mag vector) is way off so that the GPS has to do big corrections. But I cant remember if you are using AIMU or DIMU?

Anyway, at Burning Man in the desert there hardly can be many objects that restricts GPS reception so PH and DVH should work a treat there. Just allow the GPS a little time to settle the estimates before doing your shots and you should see smooth and predictable flying in DVH mode.