Herelink Wheel Modification

Hey Guys,

I am trying to use the Herelink Wheel to control a servo gimbal on my aircraft - but it seems like ArduCopter doesn’t have support for an “angle” mode. So - the gimbal just snaps back to 1500 once I let go of the wheel. Is there anyway to open the herelink up and remove the self centering stick - just using the wheel as a normal rotator? Or - is there some Lua scripting that can be added for this functionality.

A Lua script may be able to read the pwm value then process it before sending signal to gimbal.

There is a spring holding the wheel which re-centre it when released. It is possible to remove it, but the wheel component is laying pretty deep under the joystick part. Opening the controller housing will definitely void the warranty, so any hardware modification is not recommended unless you clearly know what you’re doing.

A new software update is coming soon which will add increment mode to the wheel. You may wait for a while and see if that new feature could match your requirement.

I think we might go the Lua route. I have the setup in mind - but am new to Lua. Definitely going to need to just run some example scripts to learn how this all works.

Any tentative update release date?

very soon

I was able to complete this via a custom Lua script. This is my first script w/ Lua - so it probably is pretty trash. It works in sim for me - but please let me know if you see any glaring issues.

Basically, I have the Pixhawk reporting normal pitch control to a PWM output that isn’t plugged into anything. This channel is just used by me so that I can get the normal stabilization PWM value outputs from ArduCopter. Then I take this value and offset it up or down if the gimbal control stick (RC8) is above 1600 or below 1400. There is no speed control - I really don’t need this. This offset value is updated every loop and added to the normal pitch output from the pixhawk. Then this final “new_pitch” value is pushed to the servo output that is actually connected to the gimbal’s pitch control. Does that make sense?

For what it’s worth, PWM = 1500 points the camera looking at a 45deg angle downwards. So the ± 250 PWM boundary is basically pointing the camera straight down or straight ahead (in theory). Will probably have to tweak these numbers when I load it on the actual aircraft.

Also - I am running this at 50Hz. If possible - I would like to run it faster (like around 250Hz) for smoother control. Would that be too much for a Cube Orange?

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