It's a semi lethal 130 quad.
To be honest, 10%, at best, of quad design is actual engineering that might affect flight characteristics. The other 90% is more akin to interior decorating – moving furniture around to maximize the available space (apologies to interior decorators). Almost anything that holds 4 motors rigidly in space will fly, so most of the time we're just shuffling parts around and drawing pretty lines around them.
My friends Chuck and Josh wanted a 130 to call their own and asked me to whip something up. I was dragged kicking and screaming into designing a 180 and that went pretty well so I thought I'd better give this a go.
Like the Mitsuko, the biggest problem when you go small is dealing with the 36x36 FC footprint. For Mitsuko I rotated the FC 45 degrees and eventually made it a + quad. I could've just shortened Mitsuko's arms to make a 130, but I thought Mitsuko's vertical stack would be too much for a little 130. Since a 130 is more about winter fun than ultimate performance, I thought it better to go with an H.
I started by laying out the main components in Sketchup. Even though I'm morally against dead cats I pushed the rear motors in a bit. The arms take the longest possible path to the body so there's ample room for an esc. The idea was to use Sketchup to make a grid and then take the dxf to Illustrator and put pretty lines around it. But even at this early stage I could see this wasn't going to be easy – there's an unavoidable big belly right in the middle. I started to get a real appreciation for the RotorX Atom. They made something really cool looking from an impossible starting point.
Next it went into Illustrator and I attempted pull it together. I showed this VERY preliminary attempt to Alex and he called it an un-PC name you can't call people any more and ordered me to make it look mean. Can't say he was wrong.
After much screen staring I found that if I treated it as two triangles, like a star of David, there'd be a naturally wide mid section. The concave lines organically led to a pointy motor mount.
After a little time in Illustrator I got to this point, somewhere between a little bird and a shuriken. Most micros have correspondingly short stack heights, but I hate micro components so I spec'd it for 35mm standoffs. It'll look a little wonky but it'll be a much easier build and you can use normal parts. The ambitious can always get shorter standoffs and slam it. Plus, with 35mm you can run a vertical vtx and have lots of room for your fc stack.
I ordered the turbo power train – 1306 3200kv and Littlebees, hoping that their extra mass would give me an inertia/drag ratio more like a 250 miniquad than a Nanoqx. While my parts made their way on the slow boat Henry built up a 1105 version with a pico cam, and I joined him for the maiden.
For me, it flew a bit like the Nanoqx. Too much back elevator would stop it in its tracks, if not make it go backwards. It was just too light to be flown like a miniquad, no banking and yanking in turns. To go forward, you had to keep pushing it forward, almost like flying in self level mode. The pico cam had the same crazy field of view as a Nanoqx as well, with the psychedelic distortions at the edges of the picture that gave me headaches. We had a little chuckle at Henry's expense when he said the proto was flying too fast while moving along at a walking pace. The zooming effect of that wide lens is really deceptive.
A week later my parts arrived and I built up my 1306 version. The build was remarkably easy, especially after having assembled a few Mitsukos. The only unusual thing was routing motor wires under the esc's and back over the top so that the esc's could be right next to the bells.
With a 1300 3s it hovered at the first white hash mark on the throttle stick, with a 1050 4s it starts bouncing with the absolute least amount of throttle I could give it. I strapped on a 1300 4s and it shrugged it off like it was nothing. A micro without weight concerns!
Since it's a bit of a dead cat here's the mmix numbers:
Motor Thr Roll Pitch Yaw
#0: 1.000 -0.890 0.750 -0.920
#1: 1.000 -1.000 -0.750 1.000
#2: 1.000 0.890 0.750 0.920
#3: 1.000 1.000 -0.750 -1.000
The maiden at the club field was made eventful by a slowly dying Littlebee esc. I got a few batteries in and found it to fly a lot more like a mini, with good speed and agility, and enough inertia to make it track. Jay had a nice flight as well, but by the time Steve and Alex got it it was nearly unflyable. But at least I got lots of crash testing out of it.
I rebuilt it with a new Littlebee and tested it at an indoor location, and it frikkin' rips. Ryan and Shane felt it had less inertia than a mini but for me, it flies a lot like a 180 or 250. Henry's 1105 build was zipping along nicely as well, but for me, the 1306 build really sings. It's easy to build, it uses common parts, and it flies more like a mini than a micro. It's ready!
And here's the one Chris aka Patient 0 built.
Meanwhile, Frank and Atakorn of the New Jersey crew built up a super slammed version. Check it out here, it's really cool built low profile. I have no idea how they got it so much lower while putting in MORE components! They also saved me the trouble of having to make a build log.
The final version has a couple more SMA holes for more versatility, and extended rear arms to accommodate those slightly oversized HQ props.
From the start this baby was called the Shuriken for its resemblance to a ninja throwing star. We called it that for weeks until someone released a new frame with the same name (which looks nothing like a shuriken!). I thought about going with Shriekin' since it sounds almost like shuriken, but I'm going with Shrieker so I can have Tweakers and Shriekers in my line.
I made a joke about how Shrieker could easily carry a GoPro, so here's proof.
Henry did a rebuild and retune of his 1105 Shrieker, and we met up and flew indoors. With the new tune it flew substantially better, and with a narrower lens the fpv view was much improved as well. It still felt smaller and lighter than the 1306 version but it tracked much better. We can't post video for a while because of the nature of the location, but I do like this screengrab of Henry running for cover.
We got to fly outside separately and open them up. Here's Henry at the club field:
And here's mine with a 1300 battery and a Foxeer Legend up top.
Here's a great build tutorial video by Chris Dengler. Thanks Chris!