Quad scratch build

[DarkSymphony]

Hi all, I suppose this will be my build log for my first personal multirotor project Whilst I've designed a few UAVs before (I work as designer for a small UAV manufacturer,) this will be the first project where I've had complete creative freedom (and a limited budget!)

I'm going with a somewhat unusual design approach - construction is entirely G10 sheet, with motors directly mounted. I'm planning on using Sunnysky 3508s, 12" APCs, Naza-M V2, and whilst I've designed it so it could take a Tarot GoPro gimbal, for the time being I'm going to use a Foxtech Horyzon V3. Whilst I'm sure efficiency is going to take a hit from this frame layout, I think it'll be an interesting experiment.

Here's a pic of my current design, parts should hopefully be here soon and then I can hit the CNC machine!

View attachment 18983

 

[DarkSymphony]

Update time:

Ok, so having seen the flexiness of G10 in a quad prototype at work, I figured my original design was a little on the insubstantial side (especially with torsional twist along the "arms".) Since then, I've redesigned the frame completely, making it semi modular so the arms are separate from the main body. I gave the arms a common mounting size, so in principle, the same arms can be fitted to different centre plates to build a hex or octo. Furthermore, by using motor mounting plates on the underside of the arms too, Y6 and X8 frames should be easy to make too.

Whilst in reality I doubt any further development will take place on the airframe other than running it as a quad, as an intellectual exercise, I'm pretty happy with the ability to reconfigure the frame using common components.

In other news, I changed my mind on Naza and am now the owner of an Xaircraft Super X system

View attachment 19185

 

[DarkSymphony]

Update time: So, the design changed a little, mainly some refinement and improvement prior to cutting. I also discovered that the Foxtech gimbal for the Horyzon cam was pretty awful, so I incorporated a G10 copy into my airframe.

Final airframe design looks like this:

So, with the design 100% finished, it was off to the CNC machine. Parts are cut now, but I'm waiting on a load of aluminium spacers coming from China (the last piece of this quadcopter shaped puzzle.) To be honest, at this point, I'm getting sufficiently impatient that I'm considering ordering a new set from the UK and taking the hit.

 

[DarkSymphony]

Progress report time!

Got the airframe assembled and crammed all the electronics in. The maiden flight went as well as could be expected given there were winds gusting to 30mph, but I managed to get the gains all set the following day and it was flying nicely.

Then, unexpectedly, I crashed it quite spectacularly. Turned out I'd made quite the rookie error; by connecting the SuperX to the Rx by sbus, channel 7 was allocated to both my camera tilt and RC gain, so when I was adjusting the cam in air, I was also increasing gain to an unflyable degree. I've since rewired the SuperX to the rx the old fashioned way (with lots of wires!) and everything works great.

For a first design/build project, I'm really happy with the outcome. Since taking the below photos I switched from cheapo 1147 props to APC 1238s, which has made a big difference. Takeoff weight is quite high at 2.1kg, but flying time is still around 15 min, so all in all it's not too bad. Plus, as was my aim in designing the frame, it's incredibly resilient to crash damage. The legs are perhaps a weak point (one broke in the gain crash) but everything else is rock solid.

Looking ahead, I'm somewhat tempted to convert this into an X8 in the future; the main limiting factor is that there isn't much room for a larger battery (maybe if I use 11" props on top and 12" underneath.) It'd be somewhat excessive, but given the airframe is more than capable of taking it, I don't see why not try