First Try at Quad Air to Air Filming — Or Quads IV – A New Hope

Yes I’m now up to the 4th revision of my quadcopter (sorry Scott, I couldn’t resist carrying on your Star Wars theme). I’ve now used 3 different frames and 2 different controller boards, and this is now the latest version, now with a new frame with landing skids, turnigy 1400kv motors, 8×6 props but using the same Qbrain quad ESC and MultiWII pro controller board from the previous version.20150208_141442I try to tune the copter to make it basically flyable without using the self levelling function of the MultiWii board, this configuration needed higher P setting (around 6 to 6.5) and higher I setting (around 0.2). Although I wanted to set these higher, raising them above this level creates feedback and big wobbles. Switching on the self levelling now keeps the quad reasonably stable, having these settings lower switching on self levelling generated a ‘noticeable’ feedback wobble.

So now with my new quad trimmed and stabled out (well as good as I can get it for the moment) I gave it a bit of a more sedate test flight, and tried to do a bit of tracking of other planes in the air. Although as I was flying line of sight and trying to track other planes without specifically working with the associated pilots (so needed to try to ensure that I didn’t get it their way or crash into them). The results were limited:

Sorry for getting a little close and worrying you there Mr Mike. With the wide angle lens the planes are a bit of a small dot until I was very close, perhaps a mobius with a standard lens rather than the wide angle may be better for this type of filming. I have also tilted the camera down a little for improved FPV vision, again for this air to air filming a more horizontal position would be better. The board’s program can be updated to make this dynamic from a receiver channel, but I am out of channels both on my transmitter and receiver. Also the camera is getting quite a bit of vibration and wobble, some of this is certainly down to the fact that the camera is out on a platform stuck out of the front of the quad, so is going to always be susceptible to this, but also I think the standard analogue servos I am using would allow the platform to wobble more than I would like, so I have ordered some metal geared digital servos to replace these, they should hold the gimbal more securely. I will try again once they arrive.

The change to the faster motors and smaller props seem to make the quad a little more difficult to tune, they certainly use battery life more quickly, but other than this don’t make a huge amount of difference to the quad.


Update 16/02/2015


6 thoughts on “First Try at Quad Air to Air Filming — Or Quads IV – A New Hope”

  1. Thanks Chris.
    It will be interesting to see whether new gimbal servos make any difference.
    The video quality is excellent.

    Bye the way, am I allowed to start a new topic. If I am how do I do it.



    1. I did think you had a password, but it doesn’t appear you do. So I’ve just set you up and the system should have sent you your password. I’ve also sent you an email with some quick instructions.
      Any probs give me a shout

    2. People do seem to say use metal digital servos for the gimbal to keep it steadier, I didn’t have any so tried it with normal servos. So hopefully it will make a bit of a difference. I will also see if I can fix the mounting a bit better too. The mobius camera is a nice camera.

  2. I’ve added a new video to the bottom of this, attempting to follow Barry for a little while, but got a bit worried that I was going to get entangled with him whilst he was looping and rolling so had to keep a bit of distance. And I tried the ‘land’ function of the board, just at the end of this video after Barry has landed. It seemed to have no effect, but when I turn it off again the Quad seems to shoot up a bit. Maybe need a bit better try with this. Then I landed rather heavily and the servo arm came away from the gimbal. I couldn’t fix it at the field, and after this was removed the quad seemed rather unbalanced, I didn’t have a flat surface to re-calibrate the accelerometers.
    The video is still a bit wobbly, better than before, but the gimbal seems to move about where the servo arm meets the servo. The emax servos didn’t have a big overlap so still wobbled a bit. Of the servos I have the Hexatronic seems to have the best tight fit with the most overlap, so maybe give these a go and see if its better. Metal Digital don’t seem to make that much difference. Maybe having tight fitting servo arms will be better.