Tricopter "Whirlygig" frame

[adamcooney1]

@Kevin_Erik
Just used PLA for the frame. I look forward to your next revision. I am also tweaking a version to include integrated prop guards for easier flying/crashing indoors. I will definitely post my build as well as attribute you as the source. My e-mail is [email protected] if you need to send me anything directly. I’m just learning Fusion 360 and I will start printing in different materials as soon as I feel comfortable with PLA. I’m not happy with the component alignment and I need to do some filling of some gaps. I think it was you who suggested Fusion 360 in the first place.

I really appreciate the work that You, @LitterBug, @lauka and @jihlein (and I suppose David too) have devoted to this small dark corner of the multi-rotor hobby. When I am struggling with a FC pinout, DRonin quirk or a GCS compatibility issue I come here like its a support group for people with the Tricopter virus. I’ve got a really bad case…….

https://rotorbuilds.com/build/20506

Adam

• This reply was modified 1 year, 3 months ago by adamcooney1. Reason: Added build link

[adamcooney1]

Remixed version with prop guards and a camera mount:

https://www.thingiverse.com/thing:3942223

[adamcooney1]

And it grows…… Thanks to @Kevin_Erik.
These are a blast. Now with a cat safe option.
Frame was fresh off of the printer. No post processing yet.

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[jihlein]

So here’s my rendition of Kevin’s latest Whirlygig. Weighs 49.5 grams without the battery connector or video gear.

The software is the BetaFlight unified target betaflight_4.1.1_STM32F411.hex, with a modified MATEKF411 target file, on a BetaFPV board. The modified MATEKF411 target file creates a pin configuration that supports an RSSI adc input and a non-inverted fport input. The unified target file I’m using contains the triflight 0p7 algorithms. The available ports on the BetaFPV board are somewhat limited, so as configured it must use fport.

Batteries should be here in the next week or so, so it hasn’t flown yet. Bench tests confirm proper operation of non-inverted fport, the RSSI adc input, and triflight. More details to follow….

I should also add I’ve built betaflight_4.1.1_STM32F405 and betaflight_4.1.1_STMF745 unified targets, and config files for the KakuteF4V2 and KakuteF7HDV boards. All have passed bench testing, and the KakuteF7HDV (installed on RCE Mini Tri with GPS and mag) has exactly one flight on it (triflight disabled) to verify basic operation. Lots more to test….

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[Kevin_Erik]

All i gota say is enjoy the first flight!

Guessing your flight weight with cam / batt to be 70-73 grams. Please post a flight video.

-Kevin

[jihlein]

No flight video, but a flight picture……it flies very well!

I should add I re-worked the code one last time, went from triflight 0.7 to a customized version of triflight 0.5, works much better.

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[Kevin_Erik]

Stick a micro camera on that and take it outside!

Question: What PID’s did you end up using?

[Lugh]

I’m happy to find this thread about the Whirlygig. I’m just about done sourcing parts to build the 3″ toothpick-type version. This will be my first tricopter, I’m super excited.

The plan is to go lightweight with 1s batteries. 3″ Frame/motor mount in clear Abs, 1103 13,000kv motors, HQ3x2 bi-blade, 4.8v-6v Bluebird BMS-101DMG, Purple “Play” F4 whoop FC w/ Led strip pad, Frsky r-xsr, Aio BetaFpv whoop cam/Vtx, Beebrain v2 canopy, and 450mAh 1s Gnb batteries.
I’m crossing my fingers the motors have enough power, they work great on a similar toothpick quad but it will be interesting to see how one less motor feels. I might swap in FpvCycle 1202.5 11,500kv if more power is needed, they swing the tri-blade Gemfan 3016×3 with authority.

The main question still have is if the servo can be powered from the flight controller 5v pad or if it needs an external 5v step-up/down voltage regulator? I can’t seem to find power consumption info for the sub-micro servo. Would a 0.4A or a 1A external regulator work?

Thanks!

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[Kevin_Erik]

With 1-S you’ll need a step-up BEC or risk browning out (burning up) your FC / Servo. Point being that most of the micro sized FC-BEC’s are only rated for 0.5 to 1.5 amps continuous draw yet the Servo can draw as much as 3-6 amps due to “potential” stall-current conditions. IMO its better to run 2-S and power directly from the LiPo with 100uF 16V cap in parallel. (Noise suppression) Keep in mind that the little Bluebird Servo can very easily handle 7.4V so 2-S is perfect. Besides at higher voltages (6+) the Servo response is faster and with significantly more torque.

Those 1103 motors sound reasonable and it maybe possible to run those 2S with two-bladed 3″ props.
My favorite 1103 motors are made by Xing as the BetaFPV motors have really short wire lengths. Furthermore I’ve found that the BetaFPV wiring isn’t very robust and can come unbound from the hub due to the tails Yaw action.

Xing 1103 https://www.iflight-rc.com/index.php?route=product/product&path=245&product_id=997

Here is my most recent 3” 2S build at 54 grams https://rotorbuilds.com/build/21545

[Lugh]

Thanks for the help. I stuck with 1s as that’s the parts I have. The lower Voltage Bluebird servo is on Vbatt as recommended by another forum. So far so good. My first test hover went well. It’s like nothing I’ve ever flown before. I’m excited to go fly.

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[Lugh]

I had high hopes to pull this off with 1s only. There just isn’t enough power. It hovers then slowly loses altitude. I’m switching over to 2s. New motors and HV servo. Thankfully the FC and other components work with 2s.

[Kevin_Erik]

The overall weight vs the thrust available is too low. Furthermore the servo is most likely too high of a load that the 1S can support. Its why i recommended going 2S, 7500-10000kv motors and 3” propellers. That setup should fly 3-6 minutes depending on hardware and combined weight. My best build was < 70 grams with LiPo and camera.

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