Auto-scheduler priorities explained

Hi All,

I have created a text file with a list of sats I don’t want to schedule at all (not transmitting in my region or there is some other issue with them) because I’d like to be able to capture other ones clashing with the objects in the file by observation time. Priority was set to 0.0.

After updating my station’s (2225) crontab with auto-scheduler’s parameter list by adding -P /path/to/txt_file/priorities_2225.txt it looks like I have achieved a reduction of scheduled observations per day, but unfortunately, I still see sats being observed from the pool in the txt file.

I’d like to better understand what is the purpose of the priority in the file and how one value differs from the other when say 4 sats could be scheduled at the same time having 1st one in txt file with priority 0.0, 2nd with priority 1.0, 3rd with priority 1.9 and 4th one not being in the file.

Does the value of 0.0 mean “not to schedule”?
Is the priority in use only when a number of observations are possible at a similar time (what is the time span between observations start)?
How about the rest of the observations possible to schedule when not clashing in time with the ones in txt file? Are those scheduled by means of the other provided/default parameters?

Thank anyone for putting some light on the problem.

My example txt file:

36122 0.0 T7QXLn5PryWVdjqDUfGa55 # XIWANG-1
29499 0.0 WPbJwgkLaQ6hD973hr9ZMd # METOP-A
38771 0.0 YpHpZiWytCCCcnchvkV62Z # METOP-B
28654 0.0 jfPQW4xWfTFmp7eKoPNsph # NOAA 18
33591 0.0 Bsa8dgFiYCpAuMTjZrqY5a # NOAA 19
32953 0.0 4vRcttnce4Z3nhfsQQt8kM # YUBILEINY CW
44530 0.0 xuaBFNz9x9K4aEe7sg5hoG # Taurus-1
7530 0.0 epmfL93RZ2Vf5WKK4X2auf # OSCAR 7
24278 0.0 t2ffeMh8FNf979UMF7kGaV # JAS-2
39087 0.0 j7hToyExdmZhuhWRhsutgV # AAUSAT 3
26063 0.0 qHbFqzuhyYnaexGP64PZXN # OPAL

I don’t know about the rest, but the auto scheduler will add non-priority observations to fill unused time, unless --only-priority is specified.

If --min-priority is specified, the auto scheduler will only schedule passes with a priority higher than this limit [default: 0.0, maximum: 1.0].

I learned this from the help text of the program, I have not tried it myself.

Also be aware that other people (and the global satnogs auto scheduler) can schedule observations. Such scheduling will not take your priorities file into account.


Just to confirm what @mfalkvidd already said correctly: Yes, if you set the min_priority to a value larger then 0.0 and select the --only-priority option, then the auto-scheduler will not schedule any passes for the satellite with the given norad id.

I personally do not have a complete understanding of the priorities code so I can’t give a definite answer here. But no, unfortunately it is not that simple.

Yes! If you do not use --only-priority, the scheduler will first schedule all passes matching the “priority condition”, and then try to fill the gaps by scheduling all passes which didn’t match it.

The priority conditions are defined in the get_priority_passes method. Unfortunately they are quite complex imho. I would love see better documentation of this!

Thus, In an attempt to document the auto-scheduler behavior I just started this document. Once finished I would like to move the content to the official documentation of the auto-scheduler.

So, for everyone who always wanted to take their time and fully understand how (some part of) the auto-scheduler works, please contribute here! :smiley:

I hope I was able to answer the remaining open questions for now. If there are more, please ask!


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