I'm scratch-building a new Octocopter, in the style of the Hashcopter, using square aluminum tube, and eight motors ganged as pairs with (Quad) Arducopter software.
Where is a good place to learn the factors and trade-offs in Quadcopter frame design? How long should the arms be, and what are the pros/cons of different lengths?
Should the craft be as tight/small as possible (props near, spaced evenly), or is there a benefit to having the motors out further from center?
Any tips for optimizing arm length?
Thanks!
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I need a diagram on autocad dwg to cut the machine plasma, need a scheme octocopter.se Would anyone can help me thank.
I've been looking at this recently - the Hashcopter design is alluring. There are two variables here on a symmetrical hashcopter: motor to motor, and crossbar to crossbar. Making c2c about 40% of m2m allows you to maximize prop diameter by equalizing the spacing between diagonal props with the spacing between adjacent props. Coincidentally, 40% of m2m is about the maximum prop diameter that is physically possible.
I wouldn't advise spacing the props *too* closely though, I would expect all sorts of adverse vibrations and drag to develop. What is the optimal spacing? Nobody knows. Unlike fixed wing planes with their wind tunnels though, this *is* something you could test using an accurate digital scale, and a pair of ESC/motor/prop/watt meters on an adjustable jig.
More directly, is there a preferred ratio for prop diameter to motor spacing?
If I'm swinging a 10" prop, how much space needs to be between prop tips? I've read that tight (close) motor spacing gives superior yaw control. Is there a limit to this?