PilotAware
British Forum => Technical Support => Topic started by: rogellis on February 01, 2018, 09:55:07 am
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Has anyone made some software to take the flight log (track) and output it onto a map display, to replay past flights? These systems are quite common for gliders, so you can replay the previous flight on a map and see where you have been (also for badge flights). Glider loggers can can input several data logs simultaneously, so you can see multiple gliders race each other across the map.
Cheers,
R
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I wrote a program a while back that took the output from OGN/R and converted it into a file that could be read in Google Earth. It used timelines, but I found that is function of Google Earth less that satisfactory. There was zero interest from others so I never bothered to refine it. I could dig it out and adapt to read the PAW log file ( *.trk). But only if there is sufficient interest.
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If I recall, google earth accepts kml files, which are your own position
can this accept others positions as well, because I think this has a slider bar for time, and hence would be very useful
we could probably use the additional annotations for the bearingless targets to be displayed
needs an expert web programmer, I think I could format the data - if I knew the format it required
Thx
Lee
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Two obvious routes:
1. Convert the log into an igc file (which is what glider pilots use) and use any of the gliding software - See You, or a couple of free ones (eg http://glidingweb.org/igcWebview/index.html (http://glidingweb.org/igcWebview/index.html)). Conversion ought to be trivial.
2. Convert to KML and look at the track. (Glider pilots sometimes go from igc to kml then look at Google Earth. It's quite useful. There exist igc-kml converters (eg http://cunimb.net/igc2kml.php (http://cunimb.net/igc2kml.php)
Paul
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As I said above, I have already covered the conversion to KML, from a text file. I just need to change that text file to *.TRK
Will supply an example this evening
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Paul the two references you provide, do these accept GPS traffic data in addition your own GPS data?
if so that sounds really useful
Thx
Lee
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Have a look at this KML file. It is a capture from the OGN station point of view. One with a poor range as it does not have a proper antenna yet. I don't think it will be too difficult to amend the code to plot your own flight and aircraft around you.
Each aircraft can be turned on or off, and yes I could change it to callsign rather the than Hex code. The hex is also used to set the colour.
https://www.dropbox.com/s/gx2myfirm3cmc02/testplot2.kml?dl=0 (https://www.dropbox.com/s/gx2myfirm3cmc02/testplot2.kml?dl=0)
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Thanks, this is interesting.
It is beyond my present capabilities, but I am sure if the PAW data-file could be converted to the same file-format as the glider files, someone at the club will show me how all this works. The cross country pundits are all into this flight tracking business, and will get it running in a trice.
When we get our first cross country of the year, I will ask again about converting the resulting file and running it on their standard glider software.
Cheers,
Roger
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I am not 100% sure but IGC files are only for single aircraft and cannot include traffic around you. The display software perhaps imports muliple IGC files from all the competitors? What software can do this? A quick skim of 'IGC Flight Verification Unit (FVU)Data File Standard' pdf shows nothing that will help.
GPSBable can do a lot of conversions to and from igc
I could also create individual igc files for each aircraft found in a PAW *.trk file, but that is a hell of a lot of work. If glider pilots are serious about using PAW rather than Flarm I could be persuaded.
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Paul the two references you provide, do these accept GPS traffic data in addition your own GPS data?
if so that sounds really useful
Thx
Lee
Only one of them is a display, but no I think it only accepts one track.
If you want to look at multiple tracks - See You (https://www.naviter.com/products/seeyou/ (https://www.naviter.com/products/seeyou/) lets you do 'snail races' of multiple aircraft. Keeps glider pilots occupied for hours after the event. Still need to convert your data to .igc first though.
Paul
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I am not 100% sure but IGC files are only for single aircraft and cannot include traffic around you. The display software perhaps imports muliple IGC files from all the competitors? What software can do this? A quick skim of 'IGC Flight Verification Unit (FVU)Data File Standard' pdf shows nothing that will help.
Glider loggers are single aircraft files. But the map software allows the loading of multiple single-aircraft files from multiple gliders, to produce the tracks of all the competitors on one page. They then alter the timelines to a common start-point, to produce a false race over the task.
All very entertaining...
R
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Are you refering to the software in Pauls link? Or something else?
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Paul and Rog, Had a quick look at NavITer. 149 euro is a bit more than I am willing to pay for an experimant. Do you know the limitations of the trial version?
I am willing to investigate a PAW *.trk file to multi *.IGC file converter, but it will be done at my pace. I need to fully understand the IGC format first as some of it is not important if it is not being used for competitions. For now I can test against the online IGC display tools.
At this time I have other pressing issues at home, so stand-by.
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Are you refering to the software in Pauls link? Or something else?
I dont know what software they use, but knowing glider pilots it will not have cost more than £5. I will ask them what it is called this weekend.
R
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...but knowing glider pilots it will not have cost more than £5.
:)
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...but knowing glider pilots it will not have cost more than £5.
:)
Ok, all the logger replay software systems appear to use the .IGC file format. So if you can output an OGC file, it will work almost anywhere....
http://vali.fai-civl.org/documents/IGC-Spec_v1.00.pdf
And the cheaper logger replay systems include...
http://glidingweb.org
http://www.tasknav.com
R
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Hi R,
I had a look at that document earlier this week and spotted that there is an issue. *.IGC files are primeraly using barometric altitude, where as the GPS altitude is recorded in the PilotAware track file (*.trk). IGC files can, as a supliment, also include GPS data, but I cannot see how this is used.
I need to get an answer from Lee regarding the relationship between traffic and our own GPS position. Is the altitude difference reletive to GPS or BARO altitude?
If the difference is reletive to the GPS altitude, then I can substitutre BARO with GPS alt. Then traffic and your own flight log will be reletive too each other at GPS altitudes. The danger is that these IGC file created reletive to anoth track can be circulated with recipiants unaware of the history, or that the cannot be compared to a puka flight logger data.
If the altitude is with refrence to BARO altitude then there is not a lot that I can do. You could try persuading Lee to add BARO altitude data into the Track log. Or find some info on how GPS Altitude data is incorporated in the plotting software.
IGC file sore so much data that PilotAware chance of filling a full IGC file, hope you were not planning on using it as Poor-mans Flight Logger :-) not that it woul dever bee accepted as 'proof' of a flight.
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Hi Ian (et al)
I thought I had answered this question, but here goes.
When passing information to SkyDemon, we (as in SkyDemon) use GPS data for the altitude.
All traffic data which is passed is relative (to us) altitude, so whether it was calculated from GPS or Baro is irrelevent, we only ever tell Skydemon and others, traffic is 200ft above or 200ft below.
In actual fact both barometric AND gps altitude are used for calculating the height differences, and it is dependant upon what the traffic is using as its reference.
Mode C/S of course use barometric, ADS-B can provide barometric and/or gps.
P3I and Flarm use GPS reference.
Coming back to the original request, I could add the $PGRMZ message
Thx
Lee
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When passing information to SkyDemon, we (as in SkyDemon) use GPS data for the altitude.
All traffic data which is passed is relative (to us) altitude, so whether it was calculated from GPS or Baro is irrelevent, we only ever tell Skydemon and others, traffic is 200ft above or 200ft below.
But on the PAW logging files, is the actual aircraft altitude stored (the altitude of the aircraft being flown), or only relative height between other contacts? And if the actual aircraft height is recorded - is it baro (1013) flight levels, or gps (effectively QNH) altitude?
I am surprised that glider data loggers would use baro flight levels (1013) rather than gps altitude (QNH). What glider pilots want to display for badge and competition flights is QNH altitude, the altitude above sea level, and not flight levels. Competition start-gates, for instance, are referenced to QNH, not 1013.
R
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R, there is a lot of debate about this on gliding forums in particular hangliders and paragliders, which may not have BARO recorders. Whether they record QNH or Flight levels seems to depend on the flight loggers manufacture. As well as the tasks airspace busts also have to be considered, which could be measureed with ref to QNE, QNH or FL, a right pigs ear.
For the host aircraft, PAW logs the GPS altitude. all contacts are logged as a position reletive to this. I would need to calculate Lat/Lon/Alt from the host aircraft. Is it possible to find a sample IGC file where BARO was not available?
Thanks for the explanation Lee, $PGRMZ would be nice, but in reality it can only be applied to the host aircraft.
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Ian,
The loggers used at our club are predominently gps loggers (a usb thumb-drive worn around the neck). And they are mostly gps only. Like this popular device, which has no baro facility.
http://www.flywithce.com
As I say, I cannot imagine why any glider logger would want to have a baro altitude, as this has to measure flight levels (as do transponders). GPS is much better, as it gives you a de-facto QNH altitude.
Since popular loggers like the one above only record gps QNH-type altitude, then the replay software packages must be able to use gps altitude.
R
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I don't doubt that software works with GPS alt only, I just need an example file to see how the data is presented. I assume you must have a few around ? Doesn't need to be long, a few minutes walking around would be enough.
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As I say, I cannot imagine why any glider logger would want to have a baro altitude, as this has to measure flight levels (as do transponders). GPS is much better, as it gives you a de-facto QNH altitude.
...
R
Except that most of the loggers, and certainly the more expensive ones, have a barometric pressure sensor and use that for their logging. Indeed, you need a current calibration chart before you can use them for a badge claim or if close to airspace in a competition.
The cheaper loggers, like the one you mention, need an extra (100m) margin built in for the more basic height claims, to compensate for the extra difference between GPS and pressure altitude.
Paul
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I don't doubt that software works with GPS alt only, I just need an example file to see how the data is presented. I assume you must have a few around ? Doesn't need to be long, a few minutes walking around would be enough.
The BGA logger files are kept on the BGA ladder here.
https://www.bgaladder.co.uk/DispLadder.asp
Here is an example copy from that web page
https://www.bgaladder.co.uk/dnload.asp?DSN=82FVEQQ1%2Eigc&Season=2018
Hope they show you the file format....
Roger
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Thanks Roger, I'll spend some time disentangling that sample file, but..
Inital look shows it as having a pressure Alt sensor, not what I was looking for.
HFFTYFRTYPE:LXNAV,LX9050
HFGPSRECEIVER:uBLOX LEA-4S-1,16,max9000m
HFPRSPRESSALTSENSOR:INTERSEMA,MS5561C,max16000m
I also need to get an up-to-date version of the IGC file spec. That file has lots of stuff not refrenced in the Release 1 spec
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Thanks Roger, I'll spend some time disentangling that sample file, but..
Inital look shows it as having a pressure Alt sensor, not what I was looking for.
Ah, that may be because all these files are from the ‘pros’ who have all the top equipment. I think the lower end loggers dont include baro. I will try and get some ordinary logger files.
R
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Try this file.
It has gone through my iPad, so I hope it has not corrupted it.
https://expirebox.com/download/d5d6b5f63324a9d10363abb6a09122e8.html
R
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R, i can call you R, can I 😊
That also has a Baro Sensor.
I think i will ask Lee if he can add Alt at ISA (1013.25) to the log. Lee, 🙏
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R, i can call you R, can I 😊
That also has a Baro Sensor.
I think i will ask Lee if he can add Alt at ISA (1013.25) to the log. Lee, 🙏
I'm surprised, as that was an el-cheapo unit.
Made by El-Cheapo Inc, of El-Cheapo, in Cheapoland.
Ok. Might be best to follow the herd....
R (I respond to many appellations, some not mentionable in polite company... ;) )
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If it was that cheap then it could be faking it, like fake thing with a degree in fakeology from faketown university :)
Actually they are now so cheap and small that it is not difficult to add to an existing PCB. My phone even has one!