Building a 50g Micro FPV Quadcopter

I've been experimenting with micro FPV drones and put together this one using the HubSan X4C electronics, the CASA 3D printed frame and a Hyperion FPV camera and transmitter that I bought.

The video shows how I put it all together. With the HubSan X4C retailing for about £30 on Amazon and suitable FPV transmitters available for around £25 (Eachine FPV), this is quite a cheap way to build a small quadcopter. It's not going to be as good as one which is running Cleanflight, but my aim was to get some practice flying FPV before my F3 Evo boards are delivered.

Anyway, it works remarkably well and I've been able to fly it indoors and outside using Fat Shark Predator V2 goggles. I'm going to have to modify the goggles, though, because half the time I can only see with my left eye. The screen angles are really critical and the goggles don't stay on my head properly. It might help if I extend the battery lead to take the weight off, but I might also try out some of the lenses you can buy as there's a big difference between the vision in my left eye and right eye.

The flying weight is 55g, so it's a bit heavier than I would like. Some of that is in the white 3D printed frame (12g), which I'm looking to reduce with a better design. The LiPo is a 1S 380mAh, which weighs the same as the frame. The FPV camera is only 4g, with the rest made up by the flight controller and four motors. Finally, the black plastic prop guard is from the HubSan box and weighs 3.5g. While it is removable, I'm not that brave yet.

The interesting thing is that the FPV camera is only held on by pressing it into double sided foam tape. An elastic band round it would also help, but it's remarkably solid with just the tape and any bad crashes just cause the camera and aerial to part from the frame without damage. I hit the washing line at one point, which knocked the camera free. Otherwise, even hard contact with the ground wasn't enough to knock it off. It might not be obvious from the video, but the flight controller sits on a foam sticky pad, with another sticky pad on top. Then I've stuck a piece of Depron to the pad and put another, smaller, pad sideways on the Depron which the camera is pushed into. I had made a Depron box to further protect the camera, but haven't used it for today's tests.

One final point, but it took me a while to work out that I needed to change the brightness on the goggles. I did wonder why I couldn't see very much to start with. Then there's that moment when you take the goggles off and realise that the cat has been watching you for the last 10 minutes.