Altitude hold and depth hold in pymavlink

[williangalvani]

Hello Jinkun,

Yes, that commit disabled it as we didn’t think it was good enough.

@jinkun

What’s the easiest way to implement altitude hold assuming altitude is available? I could write a PID controller for that but it will be great if I can leverage existing functions in ArduSub.

You can revert that commit and try to improve the behavior.

@jinkun

Is there a way to change the desired depth value in pymavlink during depth hold mode without using a joystick?

I’m afraid that not right now. SET_POSITION_TARGET_GLOBAL_INT and SET_POSITION_TARGET_LOCAL_NED Should be able to set a depth target, but they are only supported in Guided or Auto modes right now. It should be possible to add support for this message to Depth Hold too.

@jinkun

When I changed the depth during depth hold mode, I noticed that the vehicle jerked a little bit as you can see from the figure. As a result, the vehicle didn’t hold the exact depth when I released the depth knob.

We recently worked on the depth hold controller to mitigate a behavior just like that. Are you running ArduSub 3.5.4?