Hi, I want to build a quadcopter mostly for amateur aerial videography. I already have the frame, APM 2.6, motors, etc. just need some help on how I’d physically set up a controllable gimbal (which I don’t yet have). If I use a power module with UBEC I provide power to the PDB and the APM. Is the gimbal then controlled/powered from the APM or powered from the PDB and controlled by the APM? I was reading on some posts that people use another UBEC? I’m a bit confused about this. Thanks for the help!
Do not power the gimbal from the APM’s power rail. Most gimbals require 12V and quite a few of them with built-in controllers have a range of voltages they will operate at, up to probably a 4S battery. But it would be best to install a separate 12V UBEC for your gimbal.
The 5V power rail on your APM can provide power for the R/C receiver, your SiK telemetry radio, some external LED’s and GPS receiver. Don’t try to power other extra stuff off it.
I have two Walkera G-2D’s on my quad with a APM2.8, one carrying a RGB camera, the other a NVDI. I don’t use the FC to control the gimbals at all. The gimbals have their own controller and I just ran the signals from the R/C receiver to the PIT pins on the gimbals with a signal diode inline. The only real reason to use the FC to control it would be if you get a gimbal with no built-in controller, or want the FC to handle timed shots, etc… I use mine for aerial survey and don’t worry about any of that. I set up the cameras to take stills at the interval I want, or record video, start the cameras, take off and go fly. And handle the rest in post.
That makes sense, so control from the receiver and power from the battery via the PCB (I’m using an S500 frame). Thanks
That’s what I’d do if you only need pitch control from the radio. Some gimbals like the Walkera G-2D (which is a very good 2-axis gimbal in my experience) will require a small signal diode inline from the receiver to the gimbal’s pitch signal pin to prevent feedback from the gimbal’s controller to the receiver, and resultant “walking” up and down of your pitch control. If you run pitch control thru the flight controller, likely that won’t happen. The other advantage with running pitch control thru the flight controller is, for example, setting up a ROI shot where you want the pitch of the gimbal to focus on a particular altitude automatically, instead of manually setting it.
It can be done either way for pitch control.
The power to the gimbal will also depend on what type you choose. With 3S you can probably just go direct to most that recommend 12V power supply. If you use 4S or more, if it was me I’d use the 12V UBEC to power the gimbal, even though the specs say, like for the G-2D, that it has an input voltage range of 7.4 - 28V. In my experience with that one, running full battery voltage to it (5S) causes the servo motors to run quite hot.
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Hey Daithi and Chris,
Did you get the gimbal up and running with APM? If so would you tell me a little bit about what youre using? I dont really understand how the gimbal is controlled ideally, through the APM vs through its own controller, and if I need more than a DX6 transmitter to do it.
Do you only take control of pitch because you just rotate the drone for yaw?
Are you triggering the camera through APM?
I am starting the process myself obviously. and have read the wikis but am not sure on a path forward yet.
Are you doing any photogrammetry?
Thanks!
It depends on the gimbal. Some have their own controller and don’t go thru the APM at all. I use an APM2.8 FC in my 600 quad with a Walkera G2D and use the built-in controller on the gimbal. I can control the pitch of the gimbal with the radios directly on channel 6, but there is no connection to the FC at all. The camera is set to record or take timed photos before takeoff.
On my 800 TriCopter I’m using a LibrePilot controller (CC3D Revo) with a Walkera G3D. On that one I go thru the controller with more advanced functions. However, that’s a completely different setup not applicable to ArduCopter.
For APM with a gimbal that just has servos (no built-in controller) I would suggest referring to the documentation
http://ardupilot.org/copter/docs/common-camera-gimbal.html
Thanks Chris,
I have read the wiki it gives a good description of what to do, but im still at why and in what use case!
My quad receiver is wired up as PPM so i dont think i can separately wire a channel.
Is it essentially a choice between being able to control an axis on the gimbal with a transmitter vs have APM control the axes for stabilization?
thanks for answering my beginner questions. Ill hold off after this 
Alex
Gimbals with their own controller have gyros and accelerometers in them already. And they normally will have pins to connect a radio receiver to control pitch, roll and pan (3-axis). So there’s really no sense to using the FC, although you can if you want. But like with the Walkera gimbal, which I’m familiar with, you use a different “mode” in the built-in controller if you control it with the FC vs using the built-in controller. There’s a switch on the side of the gimbal controller that is flipped one way or the other to use the built-in controller vs external control.
I would say that the only reason to use the FC to control your gimbal would be if you get one with no built-in controller.
However, since you are using PPM and can’t run a channel to the gimbal, it may be better to disable the controller in your gimbal and use the FC to control it. In that case the docs should apply as to how to wire it up to APM. The main thing is that you don’t want two controllers trying to control your gimbal simultaneously. It’s one or the other. And if you use the FC refer to the manual for your gimbal to disable the onboard controller in it.