Suggestions for WIKI changes to help with tuning

ArduCopter Copter 4.5
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Suggestion 1:

To use the web based review tools, you have to set the right options LOG_BITMASK parameter. The parameter list mentions using “65535” as a default.

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This doesn’t make sense because it would include both Fast Attitude and Medium Attitude.

My guess this wording is for an early version of ArduPilot where there were fewer options.

Also - the default for LOG_BITMASK when installing the firmware or resetting to defaults is “176126”.

Suggestion 2:

The section on autotune offers a “general rule” that for the PID’s, the “D” should be 1/10th of P.

This contradicts the default PID’s that are set when loading firmware or resetting parameters to default: Pitch/Roll P, I, D are set to 0.135, 0.135 and .0036. Here “D” is only 2.7% of “P.”

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Thanks

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Pretty sure that Fast and Medium just use the greater of the two

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IIRC that is a two bit field pretending to be two separate fields.

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It is a 2 bit field like @LupusTheCanine suspects

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What is the correct parameter for LOG_BITMASK ???

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Yes but I think the semantics of the two bits are “whichever of the fastest of the two of these is the one that is used” not “Log in the Fast loop AND in the Slow Loop”

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Normal binary semantics apply:

00 slow frequency
01 a bit higher
10 higher still
11 the fastest

Some information is on the wiki
And for more details about which bit does exactly what, see the methodic configurator tunning guide page. It contains a table that reverse engineers the source code.

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If you put an explanation into a comment on this thread, then others searching for this information will be able to find out about it here.

In all the times I’ve googled (or used AI tools like Microsoft Co-Pilot) I’ve never gotten a hit on anything in the methodic configurator tuning guide.

But these threads are both permanent and searchable. So if you have information to contribute to this question, it would be helpful to others if you’d post your information here.

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I see. My info was limited to just the ATT message, but I see how many other messages are affected by those two bits.

For reference the table in this section

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I posted that information from my smart phone when I was on holidays abroad.
Now I’m at my computer and can post better links and more complete information.

The information has been on the this forum since Jan 2024 here and in a different form here
But the users still did not found it, albeit searchable and permanent.

The AMC website is relatively new and needs some time to raise in the SEO ranks.
Have you used the ArduPilot trained chatbot included in the tuning guide website?
That gives you better results, it has bee trained on the entire ArduPilot documentation.

The tuning guide is also permanent and searchable.

Many users prefer redacted and edited information that has been reviewed. Both mediums have their merits.