PIDs from quad to X8?

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1

Copter flies somehow as quad now and I’m going to add four more identical motors to it. Now it is quad and next it will be X8.

May I copy PIDs from quad setup to X8 setup directly or should them be changed to direction or another?

Currently PIDs are pretty close to default and I planned to do final tuning after it flies as X8.

2

Well, you’re changing:

  • The thrust produced by each arm. You’re not doubling it.
  • The moment of inertia in each axis by an unknown (but measurable) amount.
  • The response time of each arm (I believe the response time will be slower)

So, I would retune. If you want ballpark, halving all your gains should be safe.

3

[quote=“jschall”]Well, you’re changing:

  • The thrust produced by each arm. You’re not doubling it.
  • The moment of inertia in each axis by an unknown (but measurable) amount.
  • The response time of each arm (I believe the response time will be slower)

So, I would retune. If you want ballpark, halving all your gains should be safe.[/quote]

Yesterday evening (before your reply) became perfect calm weather after windy day and I tried maiden flight. As I didn’t have better knowledge I decided to change nothing. Copter in fact flew better than earlier and now feels pretty good. It is like lawnmower in air with lawnmover power but doesn’t feel so.

Today I did some fine tuning and ended almost 3DR default; P0.15 (was 0.14), I0.1 (was 0.09), D0.00?.