My first build works! had 3 flights,but can't figure out the gimbal

[Shawn]

"Big Bird" my self built X-525 with high landing legs works!!!!!
But I can not get the gimbal to work.
Got a CNC 2-axis with its own controller and there is nothing on YouTube on how to get it working.
I am using ibus/sbus on INAV and trying to turn a motor into a servo doesn't work or "I" can't get it to and taking a feed straight from the RX does nothing. I suspect its because I am using it in Ibus mode.
Only YouTube vids I can find are in really bad English and they seem to miss crucial steps because what they does not make sense.
I am using a single signal wire for control and powering 12v from the battery. Gimbal when powered up is stable and works properly but I can't get the wheel in my controller to alter the pitch.
Any advice greatly appreciated!

[hoverfly]

This may help.
https://www.youtube.com/watch?v=TRBr3VdJ7wA

[Shawn]

This may help.
https://www.youtube.com/watch?v=TRBr3VdJ7wA

It goes right up to the bit that I want the connecting to the flight controller. Then stops

[jtbutcher]

Have you followed https://github.com/iNavFlight/inav/wiki/Connecting-a-Gimbal-to-iNav and looked at the appropriate board from https://github.com/iNavFlight/inav/tree/master/docs for the correct pin outs? If you are using the omnibus f3 and are using ibus, i believe that means you are using UART3, which will stop outputs motor 5 and 6 been usable.

[Shawn]

Have you followed https://github.com/iNavFlight/inav/wiki/Connecting-a-Gimbal-to-iNav and looked at the appropriate board from https://github.com/iNavFlight/inav/tree/master/docs for the correct pin outs? If you are using the omnibus f3 and are using ibus, i believe that means you are using UART3, which will stop outputs motor 5 and 6 been usable.

I stopped reading it when I got to"( Don't use this if you have an actual gimbal controller )"

Because I have one.
I am trying to use motor 6 so is that problem? It shouldn't be this hard though.

[ched]

On my gimbal I just took rx output 9 & 10 to the inputs on the gimbal controller.

So using iBus the flight controller is receiving all the rx commands. So somehow you have to tell the fc that you want servo outputs on 1 or 2 specific outputs.

So what flight controller are you using iNav with?

I think what jtbutcher is alluding to is that if iBus input is on UART3 then that may disable Motor 5 & 6 outputs.

I seem to remember sometime ago someone was trying to get 2 servos to work in addition to 4 motors. I think he did get it working. Maybe try a search on here for inav.

[ched]

I vaguely remember the solution may have been to use pwm1 & 2 for the gimbal control and using outputs 3-6 for motors. BUt don't quote me on that, it is just a vague memory that may be completely wrong.

[ched]

Just had a quick look and it seems that this page might give you some clues
https://github.com/betaflight/betaflight/wiki/Servos-&-SERVO_TILT-for-3.1
It talks about resource remapping to have servo on ch1 & ch2 and ch3-ch6 for motors.

Hope that helps?

[Shawn]

Looks complicated, I am about to clean the whole F3 board and start again its got that messy with bits of pins and crap allover it. Desolder and start from scratch, will try and get motor 8 running the gimbal before I do, then I will know exactly what I am doing.
CLI commands.....great fun

[Reman]

Oh the joys of trying to go even just a little way off the well trodden path. :)

I spent about a week trying to get an F3 with iNav to talk to a gimbal. I read everything I could find online, And scoured YouTube (You're right, every video on the subject seemed to either be in a different language, Or skirts right over the whole sections of what you need to do). I would have just wired it up with PWM inputs, But my FC didn't support them, And most alternative boards I'd seen only allowed for 6 input channels via PWM (Not nearly enough to play with all the features in iNav). I even toyed with the idea of running a second RX just for the gimbal (Fly to a location, Hit "Loiter mode", switch TX to the gimbals "model profile" to have a look around, Then switch back to the multirotors profile again to fly to the next location) but (A) having something in the air without having instant control struck me as dangerous as hell, And (B) I think that even if my TX was happy to allow switching away from an active model, I'm pretty sure the FC would just break out the failsafe settings and come home.

In the end I gave up, And reasoning that a camera platform multirotor can probabbly survive a few extra milliseconds of control lag while flying about with a couple hundred feet of empty air all around it, I bought a cheap 8ch PWM To PPM Encoder for about 5 quid off BangGood.

I ran an RX that has 10 physical servo plugs on it (An FS-iA10b) and set the TX to output PWM. I plugged the encoder into channels 1 to 8 and the gimbals pitch/yaw into 9 and 10. I set the FC to take PPM inputs and connected the other end of the encoder to one of it's UART's. Set the FC to take serial inputs on the UART I'd used and set the RX type to PPM. It all worked straight away. To be honest, I never even noticed any lag in the controls doing it this way either.

There's probabbly going to be some people saying this isn't the best way to do it, Or say adding an extra failure point into the control system is dangerous, But it was the simplest way to get around the problem I had and I've never had any issues.

Hope that info might be useful to you mate.

EDIT - I just realised that iNav 2.0 RC3 is out. This has easy to use servo forwarding built in. I'm guessing ('Cos I haven't tried it yet) that if you've got a couple of spare motor outputs on your FC you could use a single iBus wire from your RX to the FC and use motor outputs 5 and 6 as passthroughs to run your gimbal. If you give this a try before me, Let us know how you get on.

[Shawn]

I have not gone to 2.0 yet either because I use a Chromebook and they are now only supporting windows(the devil),Linux and mac. 
I could go back to Linux but not Windows. ::)
Will look at getting it on motor 8 first. I only want pitch control to look straight down I have promised the wife I will fly her off a cliff with VR goggles on. :evil