PPK from "unknown" question

Duane Frymire

Active Member
Recently purchased T 1M locking up and radio not transmitting well, SN 25396.

Using T 1M base and LS rover. Day 1 Base started using Known point, and records data. Same project Day 2 base started using known point, Base locked up and shut down, no base file seems to be present for the day 2 session. DPOS the project and day 1 base and points process normally, However, day 2 RTK points exist that were shot during that session and PPK points exist that are consistent 3.5 ft. north and 1.5 ft. east of RTK. PPK says "unkown" instead of "bcp".

I'm assuming the day 2 rtk shots are good, but the associated ppk shots make it look like something is wrong.

Wondering what the PPK "unkown" represents? And, is there any way to associate a block of points from day 2 with the base session from day 1?
 

David M. Simolo

Well-Known Member
Probably unrelated but I tried to DPOS a file last night and kept losing connection after the upload phase. I wasn't able to accomplish the DPOS session until this morning when all went without a hitch.
 

Duane Frymire

Active Member
If you don't have a base file, you aren't going to get a PPK value.
Shawn, that's the confusing part. Why are we getting it, and what does it mean "unknown"? I've advised him to contact one of you guys and get an overnight support session or something. I've spent some hours but can't get it. Doesn't make sense; until it does.
 

Duane Frymire

Active Member
Probably unrelated but I tried to DPOS a file last night and kept losing connection after the upload phase. I wasn't able to accomplish the DPOS session until this morning when all went without a hitch.
We were able to download the day 1 base file via Bluetooth from 1M to LS, and process it. At DPOS it said no base downloaded but showed day 1 file on 1M, so downloaded while connected via Bluetooth and worked fine.
 

Shawn Billings

Shawn Billings
5PLS
You said there was no base file present. There is nothing to look at. I suspect the ppk is simply the rtk vector from the autonomous position of the base or some such. It's meaningless.
 

Duane Frymire

Active Member
You said there was no base file present. There is nothing to look at. I suspect the ppk is simply the rtk vector from the autonomous position of the base or some such. It's meaningless.
Shawn, that's exactly what I said. Seems like an autonomous PPK. But I'm not understanding how it even gave a PPK from autonomous; if that's what it did. There's no base file associated with these points apparently, so how could it generate anything for PPK? If that's what's going on, then I suggest instead of "unknown" , the PPK solution should say "autonomous". But still not sure how it even could get an autonomous PPK solution without an associated base? And if picking a "known" point in the base session is where it's getting the PPK from, then why the difference of 4 feet or so in coordinates?
 

Adam

Well-Known Member
5PLS
I have thought about this more since we talked and still think I would go back and tie a few of them from day two and use mlocal to correct it. I don't understand why the ppk results are shown at all.
 

Adam

Well-Known Member
5PLS
Shawn, that's exactly what I said. Seems like an autonomous PPK. But I'm not understanding how it even gave a PPK from autonomous; if that's what it did. There's no base file associated with these points apparently, so how could it generate anything for PPK? If that's what's going on, then I suggest instead of "unknown" , the PPK solution should say "autonomous". But still not sure how it even could get an autonomous PPK solution without an associated base? And if picking a "known" point in the base session is where it's getting the PPK from, then why the difference of 4 feet or so in coordinates?
Did you get a chance to look at the screenshots from base setup? They may have some helpful info.
 

Shawn Billings

Shawn Billings
5PLS
It's an unexpected situation (from the software side). I don't think there is anything to correct. You have RTK vectors and that's all. Switch everything to RTK. If the base coordinate for session 2 matches the final base coordinate for session 1, then you have nothing left to do. If it does not match, as Adam says, use M-Local to translate the second base to the first base.
 

Adam

Well-Known Member
5PLS
It's an unexpected situation (from the software side). I don't think there is anything to correct. You have RTK vectors and that's all. Switch everything to RTK. If the base coordinate for session 2 matches the final base coordinate for session 1, then you have nothing left to do. If it does not match, as Adam says, use M-Local to translate the second base to the first base.
Duane had mentioned on the phone that the two different base sessions were autonomous. I don't know why they wouldn't have set up the second time on the first days point and selected it from the list but maybe there was reason. I think the base screenshots would tell them if it was the same or not.
 

Duane Frymire

Active Member
Duane had mentioned on the phone that the two different base sessions were autonomous. I don't know why they wouldn't have set up the second time on the first days point and selected it from the list but maybe there was reason. I think the base screenshots would tell them if it was the same or not.
I was just trying to guess why the ppk solutions were consistently off and thought it might be because of an uncorrected autonomous base session. They picked a known point to start, but the base locked up shut down on second day, so they switched to rtn and continued. I didn't get a look at the base screenshots. I passed on your recommendation to reshoot a couple and mlocal if they don't agree with rtk.
 
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