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INDI Library v1.9.3 Released (11 Nov 2021)

Bimonthly Stable INDI Library release introduces new drivers and fixes for existing ones. Some highlights:

New Internal Guider Features

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Sorry I haven't cleaned this up yet, and thanks for your question. My intention is to make this more obvious.

GPG, when enabled, completely controls the response to RA error (but not the DEC error). So, RA Proportional Gain, RA Integral Gain and RA Minimum Pulse from that Control Tab are ignored when GPG is used (the DEC values are used, as GPG is not involved in DEC guiding). It turns out the RA Maximum pulse is used for RA and DEC. Maximum pulse is sort of a safeguard that wasn't implemented in the Klenske's GPG code , and so I kept it in place.

The GPG parameters themselves are a bit tricky. I did not modify them from their original form, and you can see how they're used in the code we got from Max Planck Institute / Edgar Klenske:
invent.kde.org/education/kstars/-/blob/m...cess_guider.cpp#L344
and I might add, I am very grateful for the use of that amazing code.

Here's a summary of the gory detail from that link:

Basically it blends the control error:
 
line 344:    
    control_signal_ = parameters.control_gain_ * input;

where "input" is the arcsecond guiding error in RA, and control_gain_ is that parameter in the GPG RA Guider Menu you showed
and combines it with a predicted error it's learned from its history

lines 363-364:
    prediction_ = PredictGearError(prediction_point + time_step);
    control_signal_ += parameters.prediction_gain_ * prediction_; // add the prediction


and then backs off a bit more if it hasn't had enough time to be confident in its predictions

lines 368-374:
     if (get_last_point().timestamp < parameters.min_periods_for_inference_ * period_length) {
        double percentage = get_last_point().timestamp / (parameters.min_periods_for_inference_ * period_length);
        percentage = std::min(percentage, 1.0); // limit to 100 percent GP
        hyst_percentage = 1.0 - percentage;
        control_signal_ = percentage * control_signal_ + (1.0 - percentage) * hysteresis_control;
    }

 
Orion Atlas Pro, William Optics ZS105, Moonlight V2 focuser, GSO RC10 w/RSF focuser
ZWO ASI1600, Astronomik Filters, ST80, QHY 5L-IIm guidecam.
KStars/Ekos/Indi on NUC10 & RPi4 w/SSD -- Ubuntu
Projects: Terrain, Polar Align, Analyze, Linear Focuser, SEP MultiStar & GPG Guide, FITS autostretch.
Last edit: 7 months 3 weeks ago by Hy Murveit.
7 months 3 weeks ago #69928

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Thank you very much Hy. This is just what I was looking for.
7 months 3 weeks ago #69933

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So far I'm loving all the new improvements in EKOS, I did have some issues with GPG RA though.
I had set the Major Period to 720 for my AZ-EQ6, unchecked estimate and left everything else as is. Trouble was that the RA started climbing through the roof after a while. Had to restart guiding and it would settle but then climb again after maybe 30 to 50 minutes. 
I reset to the default value of 480 last night and had no issues. Not sure why 480 works and 720 doesn't .
 
4 months 2 weeks ago #73710

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Isn't the worm period of the AZ-EQ6 the same as the EQ6-R Pro, i.e. 478.69 seconds? Why are you trying to force it to 720 seconds?
4 months 2 weeks ago #73715

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Hi Kevin, the only info I could find says the worm is 720:1, so presumed that was correct. Apparently not, I'll tweak it to the figure you mention.
4 months 2 weeks ago #73716

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Had another freak out in RA again last night. GPG RA set to 479s.
Reset to default, enables and estimate checked and it settled down for the rest of the night. Estimated Major Period ended up at 2298s.
 
Last edit: 4 months 1 week ago by Mark Rose.
4 months 1 week ago #73772
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On another note, resetting the GPG RA to default also cancels dithering and dither settle time so must remember to rest those.
4 months 1 week ago #73773

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