Question about migrating default PIDs to original tuned PIDs - and new ATC_xxx parameters

I’ve rebuilt my Hexsoon TD-650 after a minor crash two years ago that broke a couple of arms.

This rebuilt copter is lighter - maybe 15% or so.

I flew it with the default PIDs - and while it was stable in hover, it was a bit shaky when control inputs were applied. I’m not sure it’s stable enough to autotune.

I decided to migrate back towards the PIDs the original version of this copter - in small steps - starting with 25% change towards the old values. If this shows improvement, I might then take another step to 50% change towards the old values.

The goal is to get good enough behavior to safely do an autotune.

I put the ATC parameters from the old tune and the default tune on a spreadsheet - with the new test PIDs calculated.

I’m wondering if anyone sees any “red flags” about this approach.

The original copter used the current firmware from 2 or 3 years ago. The default tune on this copter shows some new ATC_xxx parameters - all still at “0”. Are these new parameters used yet? I haven’t set up a notch filter or done an autotune yet - so I can’t really tell if they are used yet or not.

In the spreadsheet I’ve attached, the parameters I plan to change are highlighted in yellow. The new parameters are in red.

Thanks!

I tried using the 25% increase towards the original PIDs and the copter flew OK - a bit better.

So then I went to 50% increase toward the original PIDs - and that seems to be a good place. After a 30 minute hover flight, the motors were quite cool - just barely warm to the touch.

After I get my notch filter going, I think it’s safe to do an autotune.

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