Quadframe 2-axis gimbal on DJI Phantom - Eric Cheng

Quadframe 2-axis gimbal on DJI Phantom

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I finally assembled my quadframe.com 2-axis gimbal for GoPro (€46.00, not including servos) and mounted it to my DJI Phantom quadcopter. My friend, Keri Wilk, warns me that I will not like a servo-controlled gimbal because the new brushless gimbals are so good, but all of this is a learning experience for me, and it’s worth trying out so I can experience what a servo-driven gimbal feels like, first-hand.

I’ll get this out of the way, first: the assembly video for the quadframe gimbal is one of the worst things I’ve ever seen. The person assembling the gimbal will pick up an unmarked, small screw, and screw it in to a part that is at an ambiguous orientation (all of the plates are black, so you can’t see details). I had to assemble the gimbal three times before I did it correctly. I’m sure the guy who makes and sells the frame is very nice, but he really needs to make a PDF manual.

IHere’s a purchased Emax ES08MD servos ($13.50 ea.) to use with the gimbal. They are the gimbals that are said to have been tested with the gimbal, and seem to be working fine.

I attached the gimbal to the bottom of the AG400-IS Phantom GoPro Isolation Mount ($79.00), which required just a tiny bit of dremel work (so the plates would fit together) and a two small lock washers for each of the 2 mounting screws to prevent the two adjoining plates from bending too much when they are screwed together tightly.

Connecting the two cables from the servos to the Naza flight controller (F1 for roll, F2 for pitch) required drilling a small hole in the side of the Phantom’s casing. Keri opted to use servo cable extensions, installing female connectors in the side of his Phantom, but I ran my cables all the way into the body. To enable gimble support in the Phantom’s Naza flight controller, I connecting the Phantom to a computer and ran Naza Assistant. A single checkbox enables gimbal support, but I definitely had to play with min, center, and max values to optimize servo travel ranges. I changed center values (which actually moves the servo positions each time you set it) to see where I should set min and max, and had to remove and re-attach my servo arms to get my desired 90º travel range (which is the max supported range by Naza, I’m told).

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Here’s a flight test dated April 8, 2013. Footage has been stabilized in post—you should expect to have a bit of shake when using a non-brushless motor gimbal. 

Here’s a video of gimbal, in action, dated April 14, 2013:

[youtube https://www.youtube.com/watch?v=tUc7WvdCEOE?rel=0]