Attached is some data I collected looking for the best prop for my stuff..
The APC electric are as good as APC slow fly... that surprised me..
Eddie Weeks
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Attached is some data I collected looking for the best prop for my stuff..
The APC electric are as good as APC slow fly... that surprised me..
Eddie Weeks
You need to be a member of diydrones to add comments!
Replies
@Adam: The Korean paper you reference makes the case that the Kov in forward flight has a unique relationship to advance ratio (related to blade pitch).
@all: The Wright Brothers' first powered airplane had twin propellers. Isn't it intriguing that more than a century later, we're still investigating how two propellers working together interact with each other?
I don't think overlaping props will work... One will be CW.. the other CCW.. has to be that way..
They will cross the same area going the same direction.. adding more swrill to the air...
Is that Right.. ?
Eddie
Good info guys.
I just ordered 9 NTM 3536-900 motors. Hopefully that wasn't a mistake, I see you guys seem to be testing the pancake motors, but when I was looking around, seems like everybody else is using standard profile motors? I almost went with 2836-750 motors, but a huge goal of this machine is to have enough reserve power to have a good chance of surviving a motor failure while carrying a payload, and I wasn't sure I'd get that with the smaller motors.
Anyway, I've been trying to figure out however, which props to use and thus how far to space the arms on the Octo.
I'm actually thinking of doing overlapping props, but flipping alternate motors up/down. I've got a design for the Octo with 12" props and the ideal 20% overlap (as detailed by Brad Hughey). The idea here, if you aren't aware, is that in theory, having 20-30% overlap can actually increase the thrust vs. a single motor due to some beneficial aerodynamics.
The diameter with this design works out to about 630mm, so it's a compact Octo, but with lots of power.
If I wanted to go with 14" props with the same overlap, it would require a diameter of 750mm.
And then a "standard" Octo with 12" props would be about 850-950 with 12 or 14" props.
So the potential is there to benefit with more efficient lift. And also the compact size is easier to transport. But I do wonder about stability, if the shorter arms will make it less stable? There seems to be some trend there, but I don't have the experience to say.
Anybody have any input? Wanna guess which props will be better for these motors, 12" or 14"?