Ever closer. I think the design of μ-Chuckranoplan 0002 is sound; of course, I say this with absolutely no qualifications or numbers to back it up. It’s visually engineered, as I now like to call it.
It will fly, but it’s still obese. Maybe if I pump it with helium…
Here’s the head of a Chuckranoplan after being stuffed with electronics. I elected to temporarily hot glue the two micro ducted fans onto a single carbon fiber stick pylon. The 3 cell lithium polymer battery ended up wedging very snugly into the nose cavity. The receiver and two controllers form the entrails that get shoved into the main body.
And here it is, all aseembled. The tail struts are all carbon fiber rods… well, except for one of them. Turns out that one was aluminum. Whoops.
The wire access holes in the sides were dynamically generated (read: shoving a hot soldering tip through the wall).
The final weight of everything? 14 ounces as measured by a chintzy digital hook scale. I’ve successfully built a decent brushless-powered antweight. Maybe I should have entered it into the Motorama Robot Conflict competition or something.
Yup, still looks like some kind of stoned manta ray with a birth defect.
Here’s a front view, while it’s charging. Note the tiny 2-56 screws holding the head on…
So how did it perform? Better than attempt #1 for sure, but still a ways to ago, almost all on the weight reduction side. The “flight” was sort of a very strained and awkward hover, and it actually couldn’t budge itself from a standstill. However, with full throttle on the fans and a push, the model did flare down the hallway. At least, until it ran into the side of the wall from unbalanced reaction torques from the fans. They should really be spinning in opposite directions.
I’m definitely approaching the problem like a mechanical engineer, and the laws of flight don’t really scale down to things this small (something about area vs. volume or some gibberish). Overall, it’s too well-built.
The double-walled PLA prints, while “light” in the hand, all add up when the pieces are put together. I’ve been trying to single-wall some test pieces to not much success, as the PLA just sort of sags and falls over. Before I managed to successfully execute a single-wall ABS print, I accidentally half-baked the extruder controller on MaB, so that needs to be repaired first (The test piece’s first few layers looked good, however). I’ll give single-wall printing a fair shot before manning up and just learning how to do it The Real Way with covered frame members, or hot-wired foam. The project has caught the attention of some Course XVI majors I know, who know how to do it The Real Way and may be able to get me some time on a CNC hot wire machine.
I would be nice to see a video of it hovering…
Have you looked into printing a skeletal frame and skinning it with covering film? That would almost certainly solve the weight problem, and it’s how virtually all RC planes are built.
I’ve thought about print 2D (ish) frame members for the body and wing and covering the rest, but if I’m going to do that, I can also cut the same out of balsa wood on the laser cutter. MaB isn’t sophisticated enough to make long overhanging bridges between parts without making a mess, so a 3D skeleton is kind of asking for it.