Recent diary entries
I recently bought an Holux M-1200E GPS data logger from Dealextreme. It seems to be the most affordable decent quality data logger out there with a MTK MT3329 chipset. For 50.99 USD I was supposed to pay customs in Norway, but since Dealextreme sends it as regular mail it slipped through that, and ended up really affordable.
I was a little reluctant buying it since I've struggled with the Holux M-241 before, however, first impressions are good. Using the MTKBabel perl program it is easy to extract data and manipulate settings, including adding HDOP, and setting point frequency both per meter and seconds (and speed if you want). I recommend going straight for MTKBabel and not struggle with gpsbabel.
Accuracy is good (3-6 m in general), and fix really quite fast. I've had no problem connecting it over bluetooth to my Cyanogenmod 7.2 phone, but the two devices seem to have to be quite close to maintain a connection.
I've used it for 2-3 hours at a time, so I still don't know how long it can last. Have a look at the wiki entry I made for how to extract data with MTKBabel.
Bewelcome is the hospitality network that ideally should have been as popular as Couchsurfing, hopefully OSM isn't just another factor that makes it ideally the best hospitality network...
Many other sites/services where I wish I'd have power to edit the map.
There have been some discussions on the Humanitarian OpenStreetMap Team mailing list about using smaprtphones for tracing/tracking.
I have long been tracing with my phones, first with Symbian, tried iPhone and iPad, and now primarily with Android based phones. The best apps for tracing for OSM are available for Android solely (GPS Logger, Vespucci, OSMTracker for Android).
Unfortunately I have been unable to find a single details source which can say something about the quality of the GPS in smartphones, but have relied on experience, and from experience I can say:
Smartphones are usually pretty accurate, but quality varies greatly and they will often get in trouble in steep and narrow valleys and the like.
You should not trust the accuracy indicator. I have walked for up to two minutes with my phone claiming 4 meters accuracy, while the real accuracy was getting closer and closer to 500 meters. It looked like it used some predictive algorithm to fill in when it had signals but no fix with the satellites. Also, apps (such as GPS Status) will round down the accuracy and not up, so 3,99 m becomes 3.
System bugs can give consistent skewing of position, so keep your system up to date.
Don't use any other source than GPS, they will not be reliable, nor helpful.
Phones will claim to have higher accuracy than possible considering current tech. My Samsung Galaxy Tab would for example claim 1 meter, which is better than any of the chipsets listed on the OSM wiki.
Using a high quality external bluetooth GPS with your phone will improve accuracy, reliability of accuracy and perhaps battery time.
Using external bluetooth GPS with Android smartphone
With standard Android you can use the Bluetooth GPS app to connect your external GPS to your phone. But if have the very excellent Cyanogenmod distribution 7 or newer on your phone you can simply pair the phone and the gps and select it as source in your GPS settings.
This has worked like a charm for me with a Holux M-241, though the reach wasn't very long, and the battery time for the Holux sucks.
Please feel free to transfer some of this to the wiki.
GPS Logger for Android has recently been upgraded and now has three features very fitting for OSM trace logging:
- Easy access annotation button (now working)
- HDOP logging (accuracy)
- Auto send to OpenStreetMap
Languages that have been started but have yet to complete include Russian, Portuguese, Hungarian and Japanese. Other interesting contenders include Zazaki, Interlingua, Luxembourgish and Telugu.
If you know of Waymarked Trails that are mapped, but have yet to be included in Waymarked Trails you can have them included by making relations according to the specifications in the wiki (see also the help pages).
Happy internationalized mapping!
I wanted to cite a page on the Openstreetmap wiki, and looked for "Cite" in the toolbox, but it looks like the Cite plugin isn't installed.
Where can I ask for it to be installed?
As OSM data is being used more and more there will be a need for citing the features pages especially, and the Cite plugin hadles it very well, and integrates with the Zotero citation software.
After some research it looks like the SpecialCite.php extension is needed in addition.
Do you have many not so accurate tracks from the same hike, drive or route lying around? Would you like to take advantage of all that data and merge them into a “line of best fit” / average track?
The accuracy of the points in a single GPS trace may be out by several meters. This depends on lots of factors such as the positions of the satellites when the trace was taken, tree cover, proximity to nearby buildings, position of the GPS unit relative to the center of the road etc. If many traces are taken for the same road, then the effect of errors in any one trace will have a much smaller impact on the average position of these traces. (from "Good practice" on the OpenStreetMap wiki).
Made by Michiel Faber, and given a home and documentation by Guttorm Flatabø, this is a first step, using R. With increased use and contributors we could soon have something more functional. The script comes with no warranty, use at your own risk, and please report bugs, improvements etc. on github, or directly to Michiel or Guttorm (using OSM messaging).
MapSpot claims they wanted to make an open map for Georgia, and now they've gotten their database into Google Map Maker. Their map seems to be inferior to OSM, it also looks like they might have used OSM (at least they've used Wlaking papers), so what is it?
Why haven't they just contributed to OSM, or have they?
Just wrote a blog about making maps from GPS logs from my jogging the last week. Nice way to make working out a productive excercise, see:
After three years I finally start using my account!
Hopefully I'll be contributing roads and hiking trails in the Sognefjord area.
However my first attempt has been to upload a track of a kayaking expedition. It isn't really that usable for making maps, so more there for experimenting.
Is there some way for me to have my track as a layer on top of a more complete map?