Datalogging Gps

[ranckjoh]

Does anyone have any familiarity with datalogging capabilities for recreational use GPS receivers?

 

I want to either get an affordable GPS that will automatically record a waypoint every few seconds and store the coordinates, not just make a line on a map without being able to download all those individual coordinate locations, or else hook up a datalogger that would be compatible with the basic recreation GPS receivers (any brand).

 

We use a Trimble GeoExplorer 3 at work which is great for that, but I really don't need that accuracy (or that expense or bother of differential correction).

 

Anyone have ideas or experiences that might help?

[Kerry.]

Basically able to hook any recreational GPS up to a laptop etc for logging data using several different freely available software packages.

 

Most recreational will record points based on time (distance) setings as tracks, which can also be downloaded to simple ascii files for coordinate/point extraction.

With track recording one restriction is the available track points v time interval, the longer the time interval the longer the period that can be saved.

 

There's also specific data loggers available for external logging much like a laptop can do but really all these devices are, are NMEA interfaces with memory capabilities that can be downloaded to a laptop.

 

Also there is some specific recreational models that do output RINEX and can be post-processed.

 

Cheers, Kerry.

Edited May 20, 2004 by Kerry.

[Neo_Geo]

When you download your tracks from Garmin GPSrs into MapSource, you can get the coordinates from individual trackpoints from the ACTIVE TRACKLOG. See the wealth of data that is recorded below.

 

SAVED TRACKS do not reveal as much data - you only get coordinates, altitude, leg course and leg distance - NO date or time.

 

Hope this helps...

 

Edited May 20, 2004 by Neo_Geo

[ranckjoh]

Ah, I didn't know you could get such great information off of a Garmin product tracklog. That accuracy level should be good enough for me. Is MapSource the recommended software for that? Is there a specific product name or version I should look for? Thanks for any help.

[Neo_Geo]

MapSource is kind of the interface application between the user and the various map products that Garmin offers. Any MapSource map title that you purchase will have this feature. The recommended title depends on which GPSr you purchase and what information you want available to you.

 

MapSource is the product that I'm mostly familiar with. If you'll be using a mapping GPSr, then you'll have to have MapSource to upload the map data to the GPSr. If you get a non-mapping device, then I imagine other products can display the same data as well. Some applications might even be free and downloadable from the internet. Someone who is more familiar with some of the other products might be able to tell you more about them. One free program that very well MIGHT display the data is GPS TrackMaker. Again, I'm not intimately familiar with this product, so I'm not sure what it's capabilities are - but I know that it's free

[+gbod]

On the Garmin models that I am familiar with, you can also specify the recording interval in either time or distance- every 5 seconds, or every .1 miles, for example. This is for the "active" tracklog, as Neo_Geo pointed out. Once they are saved (on the GPS for future use) they are trimmed and simplified to save memory.

[+PDOP's]

Here's an example of a tracklog from GPSTrackmaker exported as a text file

 

t,dm,53 32.48113',-113 58.71957',05/17/2004,16:16:24,701.4192,0

t,dm,53 32.48094',-113 58.79133',05/17/2004,16:16:31,701.4192,0

t,dm,53 32.48091',-113 58.93191',05/17/2004,16:16:39,702.3804,0

t,dm,53 32.48100',-113 59.17212',05/17/2004,16:16:50,701.4192,0

t,dm,53 32.48225',-113 59.58554',05/17/2004,16:17:07,702.3804,0

t,dm,53 32.48214',-114 00.05272',05/17/2004,16:17:26,703.3418,0

t,dm,53 32.48169',-114 00.62474',05/17/2004,16:17:49,704.7837,0

t,dm,53 32.48063',-114 01.12267',05/17/2004,16:18:09,705.7451,0

t,dm,53 32.48064',-114 01.66778',05/17/2004,16:18:31,717.281,0

t,dm,53 32.48055',-114 02.28841',05/17/2004,16:18:56,722.0874,0

t,dm,53 32.48076',-114 02.79327',05/17/2004,16:19:16,725.4519,0

t,dm,53 32.48120',-114 03.50717',05/17/2004,16:19:44,736.0266,0

t,dm,53 32.48374',-114 04.21912',05/17/2004,16:20:12,742.7559,0

 

I like the GUI interface of Trackmaker for editing tracks and waypoints on screen by pointing and clicking instead of in a list.

Edited May 20, 2004 by PDOP's