#SPARTAN 6“ boxframe

39 messages · Page 1 of 1 (latest)

wraith glacier
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DIY 6“ boxframe

bleak gazelle
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Please share some blackbox logs and/or flight footage of that.

wraith glacier
wraith glacier
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First TestFlight today without vtx

bleak gazelle
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I figured you'd get really bad vibes with what looks to be a very flexy frame

wraith glacier
wraith glacier
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i set even lower cutoff filters in BF, but maybe those are caused by the motors only? the strong vibration seems to happen on high throttle only

wraith glacier
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any ideas how to make it more smooth?

bleak gazelle
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build a stiffer frame

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this just can't handle 6" props

wraith glacier
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really?

wraith glacier
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maybe the vibrations can be dampened in the frame

bleak gazelle
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it's just wobbly here, dampening is used to push resonance nodes to higher frequencies, here your frame wobbles at all frequencies, it's not resonnance

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there's no fixing this

wraith glacier
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but, sometimes at certain RPM the shaking is gone

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therefore it must be resonance

wraith glacier
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SPARTAN 6“ boxframe

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I figured some vibrations in last test flight besides shaking camera mount were due to a bent propeller (as can be seen inter vid)

summer wharf
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Looks awesome! I've been wanting to try out a vertical arm bone drone at some point.

wraith glacier
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@summer wharf what is an vertical arm bone?

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an actual humerus?

summer wharf
wraith glacier
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Did it work? @summer wharf

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You’d have to angle the motors however

wraith glacier
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The frame was too noisy therefore I added some diagonal spars to resist bending and oscillation of flight controller. It’s still more noisy than most frames but allowed fewer filtering. Also important was to get rid of the folding triblade props which were also too much for the small motors. Soft mounting the motors didn’t make a big change because vibrations are mostly lower frequency. Now the quad is floaty even on 3s and flies smoothly like on rails. I also crashed it a few times, but the box design holds well.

IMG_2960.jpg IMG_2959.jpg
winged rover
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Update ?

wraith glacier
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Yes it flies better now with some added carbon struts. The advantage of this design is that it can be built at any size and doesn’t require a cnc cutter or 3d print, just carbon spars, fishing line, superglue. Well the motor mounts are cnc machined but are available very cheap. Gonna upload some flight videos later

winged rover
zealous wagon
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You might consider trying actual 2 part epoxy along with some fiberglass strips.

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I've never built a drone frame, but I have worked with both of these glues. CA is harder and prone to cracking. I'd also consider extending the tube the full width of the motor mount flat plate for added rigidity. But this is just based on my intuition, I don't have any formal training in engineering.

wraith glacier
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I use ca glue only to fix the fishing line to the carbon , the hardness of ca glue is desireable here because also the braided fishing line is not elastic as well and it soaks with the glue forming a very strong bond

zealous wagon
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Huh. Cool. So the joints that you're getting with that method are rigid?

zealous wagon
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Are they cracking over time?

wraith glacier
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if you put them on the right spot and the joints are supporting one another theres no way something can get brittle or loose because its reinforced bond tightly

zealous wagon
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That's so cool. Now youve got me curious about building my own frame.

zealous wagon
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You might enjoy the book "structures" by j.e. gordon. Some interesting stories about the transition to using math in engineering, amongst other things.

desert sun
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this dude has figured out life

zealous wagon
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That's the one. It's definitely improved my understanding of the built environment. And is approachable without having an engineering background.

winged rover
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can someone put this in diwhy KEKw /j