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GRTDecode - GRT LOG file decoding utility
BackgroundThe Grand Rapids Technologies Horizon I EFIS / EIS system has the functionality to record flights. These LOG files can then be replayed on a PFD. This was originally designed as a 'demo' functionality but its value is also now being seen in data logging. One of the attractions for me was during test flying, some of the data collection functions - notes on speed / heights etc - wouldn't be needed and the information could be extracted later. GRT didn't already have a decode program (too busy developing functionality for the PFD / AHRSs) however in conjunction with some existing users, GRT have provided the specs for log file (Thanks Jeff) and OK'd for this to be used outside the company (Thanks Greg).
GRTDecodeI've subsequently been working on a utility to extract this information into a generic form which can then be used as people see fit. The basic system is working, with some of the subtles - for example each PFD has its own analog input calibrations, and currently I haven't been able to take this into account, but most people won't notice the difference.
The original program is a simple command line utility - which takes a .LOG file in and generates XML output. The XML can then be converted to whatever people want - currently I've got a XML -> HTML rendering XSLT hosted at rvproject.gen.nz which is probably a good start for most people. Just open the XML output up in MS Internet Explorer and look at the data. I've also sorted a simple Windows GUI interface which makes it easier for most functions.
An example output 1 and output 2 are here
NB: The log files can get very big - XML is very verbose ASCII text, however it does ZIP / compress well. The current version currently produces summary records (one per second) rather than the raw feed as this keeps the file size to a more managable level.
Google EarthFor a little entertainment, if you have Google Earth installed (http://earth.google.com), and have GPS1 feed the flight path data can be extracted and displayed - a couple of examples are below.
An example of Google Earth rendering Walter CNO flight and Paul's Aeros are here
DownloadsCurrent version is 2.22
Windows GUI version download here.
Development version is 2.25 (includes different GPS decoding)
Windows GUI version download here.
A generic XLSX which might be useful for visualising the output download here.
Windows UsageExtract the .exe and .dll into a directory and run the EXE. Select the .LOG file you want to convert and the destination .XML filename. Then click 'decode'.
Command Line UsageIn its simplest form, from a 'DOS' window (Start->Run->cmd.exe) (command.com on pre 2K/XP/NT machines), cd to the directory with the binary, and run from there with something like 'GRTDecode --infile DEMO0000.LOG --outfile DEMO0000.xml'. Then open the DEMO0000.xml file in IE (sorry I haven't checked other browsers - but it is standard XML / XSLT conversions).
Other command line options are available to provide more flexibility - run "GRTDecode --help" for more informaiton.
Quick guide to recording LOG files
Example LOG filesWe will have to review how much traffic this generates, but in the mean time some example logs from Paul.
Many thanks to Paul Dye for the samples, notes and photos.
FuturesLots of things could be developed from this in future - and I'm keen to know what others are looking for. For example I think it would be neat to have a pretty Excel rendering / graphs or maybe a website upload / decode / render system - however it isn't currently a high priority thing for me, as I don't have any data from ZK-VII (yet).
Finally - if you have problems / need to send me a LOG file please can you ZIP / compress it first, any questions / bugs / comments let me know - contact details are here.