Small Trad Heli Copter

With the Omnibus F4 Nano V6 on Chibios we should now be able to create small Trad Heli FPV UAVs. The Omnibus F4 Pro V3 has been brilliant for my small planes.

I am looking for a challenge and winter project. I really want to get into Trad Heli but I do not want to spend $1000 doing so.

What do the Devs think of something like this, an ALZRC X360?

Anyone got any suggestions as to a better heli to use? I really would rather avoid 450-500 size helis for my first project.

Marc, we had one user that flew a little Blade micro that was smaller than that with a Pixracer on it. And it worked. So I see no reason why it can’t be done on a 360.

The downside to little helicopters is that they are quite responsive, so harder to tune for handling. But I think the X360 would be a perfect low-cost project to try out Heli.


If that is the case then one of these just arrived.

I can step up the 1S battery and maybe the same electronics will run in this. I will weigh them and add the same weight to see how it behaves.

It should work if you can figure out how to interface the tail motor with the controller. It has a Direct Drive Fixed Pitch tail rotor, which we do support in Heli.

Ok when I tire of flying it I will give it a go.


Yeah, it will depend on if the tail rotor motor is DC with varying voltage from its controller. Or if it is a brushless AC motor with a little ESC. ArduPilot is designed to drive the ESC for an AC motor.

Got it. I will see when I get power back - snowmageddon here in Chicago.

I am doing just the same. using the kk110 and omnibus nano v6. I converted the tail to brushless, and as it has only 4 output pwm, I soldered an extra wire for the extra pwm channel directly to the stm32. In order to work, the HAL file for the omnibus nano v6 needs to be modified for adding the extra pin soldered to the extra pwm. I remember another developer suggested that some pins related to other functions, I think UART, could be reconfigured for pwm also, that way there should be no need to solder extra wires to the microcontroller directly.

I was doing it just for fun, and there’s been a few weeks since I don’t do any more related to this proyect due to lack of time. I got it working but I had trouble making the gps and external compass to work, I think the ic2 needs some special setup, some pull up resistors I think for working all right with an external compass, as well as some weird ahrs problems, the attitude seemed to drift. The ahrs problem was probably related to vibrations. I didn’t really spend much time on it, so these issues probably would be solved spending a bit more time on it. I hope to spend more time over the next weeks.

Please keep us updated, it is a really nice project.

That sounds promising. What brushless motor did you use?

The pullups and i2c and extra PWM will be easy enough to solve. I expect some vibration dampening will be needed and that may take bit of trial and error.

You may be ahead of me in this as I likely will not be able to start this until January.

Great that we have all sorts of possibilities to do Trad Heli with smaller copters.

I am using a Turnigy D0703-12000KV as motor, and a HobbyKing XP 3A as esc. I am quite happy with both, It seems they are widely used by the micro heli users for brushless conversions.

Yes, If you look at the original controller, it is placed over a masive really, really soft double sided foam. I think my ahrs problems were probably because of vibrations. The thing is the omnibus nano is a bit bigger than the original controller, so it will take some trial and error as you say.

I will post here the updates also!

How did you attach that motor? I would imagine a 3D printed part may be the best way to do this. I will probably have a stab at designing such a part.

Precisely, I printed a small part, although it is provisional, I am not convinced at all with it, I made it too light and it broke during assembly, so I soldered it back using petg filament, so it is a bit ugly and messy, but it does the job. I will try to design a new, neater one, and try to print it with a smaller nozzle, this one was printed on a 0.4 nozzle, on a 0.15 nozzle it should be better for such a small part. I do it on solidworks 2016, I can send you the file, of if you don’t have access to a 3d printer I can make a few and mail them to you.

I do have a 3D printer. But I use a .4 nozzle and I agree it needs to be a smaller one. My printer really does a bad job of printing small parts but I will certainly give it a go if you post the STL.

Here you are! I changed the things I didn’t like of the one I printed for me. It should be easier to print now, and harder to break during assembly. For me, having the fan at maximum always helps with small parts. Also making several parts at the same time, 2 or 3, for the printer to let cool the pieces. Most times the small pieces fail to print because they accumulate so much heat because the hotend and nozzle is always on top. Let me know how it goes.

TailMotorHolderV2.STL (672.9 KB)

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Will see how I do with this. Will report back.