Servers by jDrones

Mini Talon QuadPlane Conversion

(cala2) #188

Dave: I bought this motors for my F61 Sunnysky X2216-7 1400KV as Iskees recommend, they look good but now I’m waiting new esc for some unsync issues with the old ones that I installed at first. any change is a month to wait here but they are arriving soon :smiley:

(Perth UAV - Sam) #189

Looks good!

You can come and do my UAV wiring anytime! :slight_smile:
I see that you’re wiring loom is also shorter, which is better overall.

One thing I find interesting is that you seem to working on the bench with a fire extinguisher between your feet. Is that on purpose? :wink:

(ronsand) #190

Thanks for your kind word Sam. I have done quite a bit of soldering over the years, both in work and hobby. In any case I had forgotten the ubec for the Mauch PM in the above pictures :blush: I also added a small pdb in the rear for power to the PI and other equipment. The loom is, as yours, wired such that without the safety connector inserted there is only power to the FC, PI and aux equipment (no power to the ESCs and motors.
For the fire extinguisher; I have not had any accidents yet, but better safe than sorry :slight_smile:

(Perth UAV - Sam) #191

No problems Dave.

I ran that combination through ecalc, and that should be fine. The 10x6 will likely not have enough pitch and make to much thrust, if you look at the table at throttle 84% and then across, you’ll see that your making 1139g of thrust at 68kmh airspeed. (77kmh pitch speed) That’s about 2-3x as much thrust as I’d expect you to need to have at that speed with cruise around 68kmh. That 100km long range FX was only using around 350-400g of thrust, but at around 50kmh.

So a 10x6 will fly, and also takeoff and climb well, but it won’t be very efficient at cruise. A 10x8 will be better on a quadplane setup to optimise cruise, if not maybe even more, or otherwise you might have to go down to a 9" diameter. You’ll notice on the 10x8 it gives some warning’s regarding stalling prop on the ground, but because of the QP we don’t need to worry about it, as explained previously.

By the way ecalc is a good way to get your bearings around motors and props :wink:

(ronsand) #192

How are you guys powering and connecting the servos, and what would be the preferable method these days?

  1. connecting them directly to the output rail and powering the rail with a bec (+ Zener diode)

  2. powering them from a bec and connecting the signals to the pixhawk. Are you then also connecting the servo ground wire to the pixhawk
    Below is and below is a bec with a powered rail for servos (the blue wires are the signals. The power cable on the left is NOT to be connected to the pixhawk). A separate bec is then thought to power the output rail. A Zener diode is again connected to to condition the power.

(Greg Covey) #193

If you’re using a Pixhawk, simply connect the servos to the Pixhawk outputs and feed a separate 5v BEC into an unused output or aux port. Don’t connect the BEC to the RC or SBUS pins that have the 5.3v Power Module supply on them. The separate 5v BEC then acts as a redundant supply for your Pixhawk and will throw an alarm if the Power Module goes bad or is unplugged (for testing).

(ronsand) #194

Yes I guess that is a good enough solution on a small plane like the MT :slight_smile: On larger ones with more powerful servos I have usually powered the servos directly.

(Perth UAV - Sam) #195

In general one should always have the servo ground connected on all PWM outputs, it’s also good practice to avoid adding connectors as potential failure points and having different lengths, or poorly routed ground and PWM signal cables. For the MT directly using the PXH is more than adequate.

I see you have the twisted cables sorted already, so that’s something I can’t add. :slight_smile:

(ronsand) #196

All good points Sam, and yes I usually twist the cables when possible :slight_smile:

(ronsand) #197

Sam, it is not completely clear to me from the Mozzie instructions, but I assume you are using one BEC for the servos (connected to the aux output rail on PH) and one BEC for the PI (also powering the PH through usb).

It looks like these are placed outside the avionics box. Is this correct?
Any reason for not putting them inside the if there is space (heat, RF noise etc)

(Perth UAV - Sam) #198

You are correct.

We put the UBECs externally mostly because for the competition we wanted to be able to replace them fast and easy. The RF Noise was a secondary consideration. Also the pi UBEC runs the LED strip light, and was easy to incorporate there on the same connector as well. In general I try to avoid having power supplies/ESCs near avionics. The avionics packaging was more born out of necessity, in that we wanted to replace that with just two screws as well in the competition, and the fact that I’d had grown tired of constantly rebuilding the avionics in new airframes after a series of unintentional crash tests resulting from BlHeli dropping PXH PWM frames in hover. :wink:

(ronsand) #199

Thanks for clarifying and giving your thoughts on this :slight_smile:

(sgloor) #200

Yep - the colours are what tape I have in the box at the time. Primarily for orientation as all my planes have stripes on the top going from root to tip and the bottom going from leading to trailing edge. I fly wings a lot and any its very easy to lose it without something to help

(James Pattison) #201

You guys seem to be on the bleeding edge… if you haven’t seen it, please have a look here: New Loiter Mode - Alpha Testers Wanted
and consider doing a couple of flights with Leonard’s new loiter. Big warning though. It is a significant change to a number of controllers and modes, so may have some as yet undiscovered implications (particularly with quadplane and sub, which are less tested).

(jean-marie BOUDET) #202

I’m building a qplane mini-heel identical to the one you’ve built and put on a great online tutorial.
I have three questions whose answers I have not answered
1 which lengths do the quad arms?
2 could you give me your param for pixhawk?
3 the wiring diagram on the pixhawk to be on because I am new to this type of machine.
In France nobody is on this type of machine and I take this opportunity to thank you for the quality of your work.

(Josh Slager) #203

How are you guys picking what 5 flight modes to assign to your radio switches? And are you overriding the 6th mode as manual?

(Greg Covey) #204

Hi Josh,

You can set the flight modes and channel used in the Full Parameter List and bypass the GCS GUI.


As for the flight modes used, it all depends upon your needs. During testing phases, I would add more QuadPlane flight modes to test hover and sensors like the BARO and GPS. My initial transitions were always QSTABILIZE to FBWA and back. I later added CRUISE mode to test the AS sensor. Next flying season, I’ll continue with QRTL and AUTO mode testing.

(Josh Slager) #205

Thank you , Greg, that was what I was thinking. I was not sure if overriding mode 6 manual would cause problems.

My thought was:

QRTL hybrid

(Josh Slager) #206

I was able to do a kinda successful hover maiden today… but it feels very underpowered and the quad motors came down very hot… Am I underspecced?

TBS endurance motors 2206 1450kv with HQ 7in 7x4.5 props. I should be putting out 1100g thrust per motor and My AUW with a 5200 4s was 2365g

(ronsand) #207

Without having the exact spec on those TBS motors I have a feeling that you are a bit low on thrust to weight ratio with the 7x4.5" props. If the motors can handle the extra current, you might consider trying a bit larger props like 8x4"

Since the motors where quite hot on the 7x4.5" the larger props might also be to much. In any case, with these smaller motors you should keep the hovering to the bare minimum as they just are not as efficient as larger ones with larger props.