The story of a 3D and FPV quadcopter.

[BladeScraper]

As you may know a couple brands have now released 3D quadcopters. For example the Invertix 400 by Encore RC, and the Align Leap 3D Quad. Even the Blade 200QX has been converted to a 3D quad by Blade.


I just think these things are great.


The Stingray 500 by Curtis Youngblood is a 3D quad but its pretty complicated and doesn't crash well, as well as being about $800 to build. They use variable pitch rotors, as well as a single motor (with belt drives to each motor) and a special flight controller to control it. (TG-Multi)

Quads like the Invertix and Leap 3D, they are a bit different. They use fully symmetrical propellers, powerful motors, and... wait for it.... reversible ESC's. The SimonK has been perfecting reversible firmware for several years now, there is a huge thread on RCGroups about it. Basically, from 0-50% throttle is negative throttle, and 50-100% is positive throttle. The load on the ESC and motor during the reversal is pretty intense which is why you must have very powerful motors and ESC's bigger than you normally would have, otherwise it goes poof and releases the magic smoke.


These are just the coolest thing to me (after helicopters )


So I decided to build one myself.

Thanks to many helpful people on RCGroups and HeliFreak I have come up with a good setup for a powerful 3D quadcopter.

I'm going with

SunnySky X2212-9 1400KV Motors
RTFQuads 30A RapidESC Flashed with Reversible Firmware
HQProp 8x4.5 Symmetrical 3D Props
Zippy 1800mAh 4s 40C LiPo
Flip 1.5 with 3D Firmware


1400Kv may seem very high for 4s, but because the props are symmetrical they are super inefficient, they must turn much faster to achieve the same thrust output compared to a normal prop. 1800mAh may seem small but we are trying to keep the weight down here.


I'm going with the $10 F330 frame from HobbyKing. I actually bought two in case I break one because they are so cheap and the perfect size.

This thing is gonna be a rocket

However, I also enjoy FPV and AV.


I also bought some other stuff. In an attempt to make this quad capable of FPV and long flight times, I also bought some 9x4.7 SF propellers, a 3s 5000mAh (!!!!) battery, and a 5.8GHz 200mw (not very powerful I know but it was on sale for $50 at FoxtechFPV) FPV system. I plan on using my GoPro for FPV. I also got an adapter that would plug directly into the GoPro and to the FPV transmitter that would eliminate long cables and adapters. The adapter has a power lead so you can plug it into the FC to 5v and charge your GoPro while you fly. Pretty neat



Here's a video to keep you waiting

 

[BurningArmada]

That is really awesome! Great job :applause:

 

[Cyberdactyl]

They are indeed cool.

One thing to keep in mind; *Lots O props*

 

[BladeScraper]

yeah I have 4 spares


not gonna be enough

 

[jhitesma]

I've actually been thinking about experimenting with this on my knuckle. I'm running the SS Angel 2212-9 1400kv's already (though only on 3s) and they're nice but it's not quite a rocket on 8x4.5" props and 3s. (And my flight times are a few minutes lower than they were with my old HK 24g 1300kv motors I was running before, though the overall performance does seem better....it could be my 2200 packs showing their age though as well.)

But I'm only running 20a ESC's and haven't had the money or drive to upgrade to 30a and flash reversible firmware yet.

Very curious to see how this goes for you. Of course now that I'm using my knuckle to experiment with TL it may be awhile before I could use it as a 3D test bed. Still, would be fun to have the first 3D knuckle quad

 

[BladeScraper]

The RTFQuads 30A ESC's are only $10, you just need to flash he may even flash them for you if you ask him

Going from 3s to 4s will be a huge increase in power, that's a 4600RPM increase in prop speed.



I am wondering how much power it will have with the 3s 5000mAh, that battery weighs twice as much as a 2200mAh 3s. I mean I will be running 9x4.7 SF props so it should be fine and have great flight time but I wonder how much pullout power it will have especially after adding the FPV stuff and camera

 

[BladeScraper]

I am planning to eventually buy another set of the reversible props, and some of the 9x4.7 and possibly another 3s 5000 (if it flies well with it).

One day when I'm bored I may even try some 10 inch props on 2s 6600mAh just to see if its possible, that would be a LONG flight (though not very eventful)

 

[jhitesma]

The RTFQuads 30A ESC's are only $10, you just need to flash he may even flash them for you if you ask him

Flashing is no big deal to me. But $40 is right now Plus that frame is being used for another crazy project right now. Maybe in a few months. But I've got to get some new batteries, new ESC's for my twitchity quad, and really want some KISS ESC's as well before I'll have money to put into a 3D experiment.

If only I had the time and money I had 10 years ago

 

[BladeScraper]

Flashing is no big deal to me. But $40 is right now Plus that frame is being used for another crazy project right now. Maybe in a few months. But I've got to get some new batteries, new ESC's for my twitchity quad, and really want some KISS ESC's as well before I'll have money to put into a 3D experiment.

If only I had the time and money I had 10 years ago

if only I had the money I had ten years from now...


Lol yeah but I understand. I have been saving for months and months and months to build a 3D quad, while having to buy replacement parts for helis during that time

 

[x0054]

Doesn't it make your brain hurt though to hear those motors screaming out as they reverse rotation! The loads must be enormous! 3D flying is really cool though!

Considering how much load the motors have to deal with, I wonder if a reversible ESC system is really any more reliable then the variable pitch system. I have yet to see a happy medium, a veritable pitch system with 4 motors. That way you can use both pitch and RPM to control thrust. The benefit would be that you can run the props at higher pitch and lower RPM for efficiency, and then instantly bump the speed and drop the pitch for acro mode.

Perhaps a specially designed motor with a built in control color and 4 way electromagnet controlled pitch system. So you would have 2 positive thrust positions, and 2 negative thrust positions. The trust of the motors would be mostly controlled via RPM, but for reverse thrust, the motor would simply flip the blade pitch. Any way, I am just rambling again with my crazy ideas.

On another note, be careful with GoPro FPV. I tried it, and it works ok, but it has about a 150-200 ms delay. I measured it my self, after hearing people talk about it. It's not bad at all on a slow moving quad, but if you pick up speed, and say get up to 40MMH or so, all of the sudden your quad is 10 feet away from where you think it is. I am still a pretty bad FPV pilot, so maybe it's just me, but it makes it very difficult for me to fly FPV fast.

 

[BladeScraper]

I also plan to use a Mobius to see if its any better

 

[Craftydan]

Having heard a few of these in flight . . . no. You hear the motors spin down, then you hear them spin back up again. honestly it sonds no different than hearing a motor spin to full throttle from idle, and while the thrust curve isn't as instant as you'd like, the loading curve is no different than punchign full throttle . . . it's just over twice the duration.

Yes the VP solutions are better performance wise . . . but all those tiny moving parts . . . might as well drop to a single rotor and fly a conventional heli.

 

[Craftydan]

I also plan to use a Mobius to see if its any better

It's always worth a try, but from the reviews I've seen the two are comparable, with the mobius just a touch behind the Gopro, depending on mode and model. Either are easily flyable in open space with a gentle platform, but twitchy and fast can be trouble. Pitch and roll problems can be eased with lower rates and higher expo, but if your throttle is touchy and your platform light, it's hard to overcome the pilot induced oscilation while trying to maintain hover with a visual lag. As you're likely aware, you've got to stay ahead of the airframe with throttle, or you'll chase it around the sky . . . FPV camera lag will force you to stay just that much farther ahead.

 

[BladeScraper]

What's a good, cheap camera that has the same USB plug (or 1/8in jack) output with decent quality?

 

[BladeScraper]

Is this one good? I plan on using it for FPV and using the GoPro for video recording..

http://www.foxtechfpv.com/fh20c-mini-cmos-420tvl-812v-camera-pal-5v-optional-p-185.html

The video of it seems decent, enough for FPV. And its only 20g.

 

[x0054]

I had good luck with this one:

http://www.amazon.com/gp/product/B00LL4KWZC/ref=oh_aui_detailpage_o06_s00?ie=UTF8&psc=1

It's a 600TLV, shipped by Amazon, so you can have it in 2 days, and it's vary easy to mount due to it's small size. A word of warning though, it runs on 5V, even though everywhere through out the manual that comes with it it claims to work from 12V.

 

[Balu]

I can't even get my head around flying a multirotor the right way up. I've just killed two props and two arms (fun fact: not the one with the props) last weekend... Now I'm not sure if my quad is half broken or half intact.

And you want to fly upside down... tssk.

 

[BladeScraper]

I had good luck with this one:

http://www.amazon.com/gp/product/B00LL4KWZC/ref=oh_aui_detailpage_o06_s00?ie=UTF8&psc=1

It's a 600TLV, shipped by Amazon, so you can have it in 2 days, and it's vary easy to mount due to it's small size. A word of warning though, it runs on 5V, even though everywhere through out the manual that comes with it it claims to work from 12V.

I'm gonna try that since its so cheap, thanks

And the 5v thing is no worries, I will just power it using the BEC (plug into a spare port on the FC. Will do the same with the GoPro.). The FPV transmitter will be powered by a 12v BEC I bought.

 

[BladeScraper]

nevermind

 

[BladeScraper]

Got my motors