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Permalink Reply by Andre S on August 2, 2012 at 2:37am

Hi,

Check your PID settings. There were changes in the "interpretation" of their values, meaning in order to get the same or similar behaviour back you need to actually scale some of them. There is more detailed information in the 2.5 release discussions.

Good luck..

Andre

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Permalink Reply by Asaak on August 2, 2012 at 3:11am

problem is it says

This has been fixed by making the PID library calculate the delta time internally, but it means that existing HDG2RLL_I and HDG2RLL_D values  will be incorrect. I have fixed the defaults, but if you have your own settings for these, you will need to drop HDG2RLL_I by a factor of 5, and raise HDG2RLL_D by a factor of 5 to get the same result as for the previous release.

So do I need to substract and add, or divide and multiple this values respectively by 5 to the current bixler param file values?

thanks!

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Permalink Reply by Andre S on August 2, 2012 at 5:54am

Would be great if there was better documentation about this available. I haven't looked at the code changes (not to mention I'm not a developer :) and haven't tried myself the new code. So do this on your own risk:

Based on my understanding, the change in navigation control is now computed more frequently than previously (that's a multiplicative factor), which means that HDG2RLL_I (which is the "integrative" term) should be divided by 5, while HDG2RLL_D (which is the "derivative" term) should be multiplied by 5. That's the only change that makes sense to me. Maybe someone else can confirm this. I plan to look at the code before actually flying it myself but I have other problems at the moment.

A

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DeveloperPermalink Reply by Andrew Tridgell on August 2, 2012 at 2:51pm

Hi Asaak,

The PID settings for stabilisation (in stabilise and FBW modes) didn't change, so the change in response to stick input is not expected. Do you have tlogs of flying with the previous version versus the current version that I could look at?

Cheers, Tridge

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Permalink Reply by Asaak on August 3, 2012 at 1:21am

Andrew,

unfortunately I don't, because there is something weird going on with dataflash as well, ( same problem as guys from mygeekshowdotcom ).

As I said, seems to work really well, although when I enter inputs, specially pitch stick, the behavious from the plane is to counter react sharply to my movements ( lets say, if I pitch up then it responds with a sharp pitch down ).

I uploaded 2.50 with default parameter settings? Before I fly with it..do you thing it is going to work? The only thing that surprise me is the hard response of the rudder in stabilization mode compared to the smooth one with bixler.param.

Anyway, if it doesn't work and if there is not any other suggestion from you guys I'll probably go for bixler.param, knowing that issue I have with stabilization.

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