Using tracklogs to validate DIY perms

[toontra]

new system for online entry here

Audax UK DIY Events

Thanks Martin - this is good news!  Two questions - reading the notes it says not to save the track to the GPS unit.  That would be OK for anything up to 300k, but when I do multi-day rides I save the track in the Vista HCx at the end of each day, so ending up with multiple files.  They seem very detailed and not over-compressed (i.e. they show 20-yard deviations from taking a wrong turn!).  Is it still the case that these would not be valid?

Also, if the tracklog is interrupted for any reason (changing batteries, losing signal) then the tracklog is divided into segments (denoted by the prefix "seg").  At the moment I open the tracklog with a text editor and remove these bits, thus making a single track.  This is much better for loading into Ascent or other readers.  What would AUK's view be on this sort of manipulation?

[Martin]

new system for online entry here

Audax UK DIY Events

1. Two questions - reading the notes it says not to save the track to the GPS unit.  That would be OK for anything up to 300k, but when I do multi-day rides I save the track in the Vista HCx at the end of each day, so ending up with multiple files.  They seem very detailed and not over-compressed (i.e. they show 20-yard deviations from taking a wrong turn!).  Is it still the case that these would not be valid?

2. Also, if the tracklog is interrupted for any reason (changing batteries, losing signal) then the tracklog is divided into segments (denoted by the prefix "seg").  At the moment I open the tracklog with a text editor and remove these bits, thus making a single track.  This is much better for loading into Ascent or other readers.  What would AUK's view be on this sort of manipulation?

1. Yes import the whole track from the device and send it to a participating DIY org; not entirely sure what not saving it on the unit means.

2. If the tracklog is unclear I open it up on Mapsourse to find out what is going on; it's usually fairly easy to work out which tracks are the actual ride and combine two or more tracks together to get a total distance and time. No need from my experience to try to combine it;

the gpx validation program also shows a map of the route so we can work out where you have been and when and the whole system works very well

Danial's probably a Bear of Less Little Brain to answer the finer points   

[toontra]

1. Yes import the whole track from the device and send it to a participating DIY org; not entirely sure what not saving it on the unit means.

I was referring to the bit in the "DIY by GPS guide" which says:

Do not save your tracklog on the gps unit at the end of your ride. This compresses the tracklog and could make validating your ride more difficult. Instead, upload the tracklog from your GPS unit straight to your computer when you get chance.

[fuaran]

On most Garmins, if you choose to "Save" the track, it will compress the track to less than 500 points, and it strips out all of the timestamps. I think its the timestamps that matter for DIY validation, as you need to prove what time you were at each control etc.

So instead, you should always download the "Active log" (which has all of the timestamps) from the Garmin, without saving it.
Or the best option, if you have a Garmin with a memory card, is to set it to log the track to the card. Then it will store it in full detail, with timestamps, as one GPX file per day, and you don't have to worry about running out of memory.

[toontra]

Or the best option, if you have a Garmin with a memory card, is to set it to log the track to the card. Then it will store it in full detail, with timestamps, as one GPX file per day, and you don't have to worry about running out of memory.

Ah yes, I understand!  Yes, I do save to a memory card and this keeps the tracklog in full detail.

[Martin]

thanks for pointing that out fuaran; yes we need an active log uncompressed straight from the device to be able to validate it; without dates and times (and presumably elevations too for AAA) it won't work.

if you are a regular user of this scheme it's also very useful to name each tracklog you submit with an easily recognisable name for future reference; I personally don't like opening the gpx files with Mapsource as it then saves them as .gdb by default which don't work; although sometimes have to.

[phil d]

if you are a regular user of this scheme it's also very useful to name each tracklog you submit with an easily recognisable name for future reference.

Perhaps a convention agreed between the GPS validators would be a good idea.  I would certainly be perfectly happy to rename the files to a name convention that suits you.  At the moment the name is merely the date I rode as created by the GPS.

[RichForrest]

I name every ride/gps file I do with what it was, usually the same as I've put on the entry form. e.g. Spalding Mildenhall or East Anglian 300 ect
I don't think the name matters as long as the information needed is in the file.

[Martin]

I name every ride/gps file I do with what it was, usually the same as I've put on the entry form. e.g. Spalding Mildenhall or East Anglian 300 ect
I don't think the name matters as long as the information needed is in the file.

I do the same before I even ride the event as that's how I navigate; and then just save it under the same name as a gpx for validation

[Jord]

I rode my first Perm by GPS on Monday and must say it is a massive leap forward (well for those with a GPS!) and will be doing all my perms this way from now on.

Brilliant idea.