Following the last post I had to take the hexacopter offline and tear it apart in the shop. Fortunately I found a way to take the one loose arm off and fix it, without having to tear apart the entire bird. That would have been a real pain.
When reassembling, I used some slightly different and thicker double sided tape for the SuperX flight controller. I also was able to clean up some of the wiring.
The first test flight (video highlights below) was quite amazing. First I was amazed that the thing even flew. In fairly strong winds it flew very well.
The video above is nearly flawless. I’ve been working toward this for so long. I’m thrilled to be at this point in the development of this platform.
Upon examining my flight logs I found that the vibrations this time were the absolute best and lowest I’ve ever achieved. Perhaps the arm was loosening causing some of the old vibrations or perhaps the thicker and spongier tape holding the flight controller on made the difference? Perhaps both.
Whatever the reason, the results are fantastic. All I need to work on now with the build is lowering the gimbal a bit to get the props and arms out of the camera frame.
One other slightly irritating thing I fixed was the landing gear. One leg was slipping/rotating like arm #5. That’s all fixed too. Once again, another possible small source of vibration.
Hope to get more batteries and and FPV system soon.
I’ve been working very hard to eliminate the vibrations of my big hexacopter so that the aerial video is not vibrating, blurry and full of video jello. I decided after much reading that I should try to move the batteries and gimbal/camera to the center of the bird, rather than having the gimbal far forward and the batteries far back to act as a counterweight.
The results are dramatic, and better. My vibration levels have been greatly reduced and the bouncing and video problems are gone. I suspect that the “rail” system used on this bird to hang the gimbal is a little too loose and when the gimbal is way out front the vibrations are magnified.
Check the log files below. This first one is the old setup with battery back and gimbal front. Note the vibration levels.
Now look at the new setup. No change in any electrical settings. Just moving the batteries top-center and gimbal bottom-center.
Casualties
Due to the change in setup I had to modify the placement of some items, and simply get rid of others. The neat clear dome which looks SO cool had to go. The batteries on top make it so the dome will not fit. I also was able to remove two of the larger battery mounts, which attach to the rails. I was able to remove a couple of different cables which became unnecessary with the removal of the dome. Lastly, I removed the FrSky GPS telemetry unit, which has never once locked in on a satellite.
The good thing about removing items is making the weight of the unit lighter, which results in longer flight times. I also think perhaps those rail mounted battery mounts were contributing to the vibration.
There’s a small problem with this setup which did not happen with the previous setup. Since the gimbal has moved backward to the center of gravity, the arms and blades of the hexacopter are sometimes visible if the copter is banking or braking enough. I will have to lower the gimbal down via some kind of spacers. How far I’m not sure. I’ll have to just do a simple test by holding the camera with my hands and looking in the viewfinder.
Since October 2013 I’ve been modifying a DJI Phantom quadcopter to try to achieve smooth and high quality aerial video as well as high quality aerial still images. I believe that I’ve got my Phantom performing the best one could possibly perform, and the video/photos the best I could get out of a GoPro 3 Black.
I found the GoPro to be very limited and the still image quality to really suck. I also found that despite the custom gains and different propellors, the Phantom gets thrown around in the wind due to its smaller size. Those factors made me decide I needed a larger and more stable platform so I could carry a larger, higher quality camera than a GoPro.
So I built a large hexacopter. Since then I’ve been doing the same tweaks to the hexa, trying to get all the little bugs worked out and achieve high quality aerial images. Then it dawned on me that my camera setup alone weighed more than my entire Phantom setup! Naturally the next step from there was to strap the Phantom to the bottom of the hexacopter as a small demonstration and different perspective. I used to worry about adding 20 grams to my Phantom for fear that it would fly poorly and I’d reduce my flight times even more.
From the video below, you can tell that 20 grams doesn’t mean too much now.
My new rig is still in the tweaking stage. During the build of the new rig, I managed to get my Phantom set to my satisfaction, and there are still situations where the bird will come in handy.