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Simple F9P (rtk) howto

Diposkan oleh grin pada 14 November 2021 dalam English Last updated on 21 November 2021.

Simple uBlox F9P howto

I got a question about specific usage of the F9P from zero to hero, so, here’s some summary from the beginning.

It is simple and almost hassle-free.

I got my board from uBlox directly but I guess it works the same with all the F9P boards. The board came with an external antenna (if you don’t have that you definitely have to find a good one, makes a lot of difference), and an USB-B cable for power.

As for the hardware, you need:

  • power source; I am using a 10 Ah powerbank which is enough for 10+ hours (probably even more)
  • a box, to put the board into, and preferably stable within, either by screws or some foamy stuff. The connectors are said to be sensitive, so try to find a way to relieve any stress on them.
  • for the external antenna you should find a way to keep it at the top seeing the satellites. My antenna has a strong magnet and I got a metal plate so I usually put the antenna outside of the top of my backpack sticking to the metal plate inside.
  • You need a mobile phone with bluetooth. Preferably Android, since I can’t help with iAmrich models. (Theoretically you could use a laptop but, uh.)

The board does not really need any setup, but there are freely available windows® programs turning the internal knobs. Since the board came with Bluetooth enabled I didn’t need to fiddle with settings (but I’m a fiddly type, so I have, but you don’t have to).

For the phone you need an app which can

  • connect to the board by bluetooth
  • able to retrieve an NTRIP stream from the network (about that later)
  • can send the stream to the board
  • can retrieve the NMEA log from the board
  • and preferably can provide mock locations for the phone.

There are two free apps available at the moment I am aware of:

See full entry

Real Time Kinetics

Diposkan oleh grin pada 3 November 2021 dalam English

Real Time Kinetics (RTK)

For half a year now I’m walking, biking and generally moving accompanied by an uBlock F9P unit, which is a precision multichannel GPS receiver board with an external antenna and bluetooth connection to my mobile phone. The phone receives correction stream (NTRIP) by mobile net and uploads it to the unit, which in turn uses the correctional data to fix up atmospheric noise in the GPS signal.

The result is a GPS position way more precise than a phone.

There are 3 usual states:

  • RTK - or “Real Time Kinetics”, when there is both satellite and internet data is available, and the base station of the stream is near. It means precision between 50 centimeters up to 5 centimeters! Imagine it like not only it’s visible when I go to the other side of the path but the track even show when I turn around, since my backpack makes a 30 cm circle around. :-)
  • FloatRTK - is when the precision “floats” from a known-good position, which in practice mean 1.5 meters up to about 90 cm (on average 1 m). When I am within 100-300 km of a base station and I’m moving in a forest this is the most usual state.
  • DGPS - when there is no RTK fix (usually due to no mobile network or blocked satellite receiving) the “normal” differential receiving mode is active, which means 3m - 1m precision, closer to 1.5 m on average, thanks to the external antenna and multichannel receiver.

When I am on FloatRTK or RTK it’s amazing: it can get back to the same position everytime, later on the day, or on a different day, which basically mean that the position is exact. I can draw a track with 50 cm precision and try not to draw that much detail on OSM (not to make anyone mad seeing fixes of centimeters along :-)).

See full entry

norc.ro

Diposkan oleh grin pada 9 November 2010 dalam English

I think I'm guessing right that those LOTS of GPS tracks with wildly detailed street coverage in selected Hungarian cities which simply isn't drawn in the OSM map are actually offered by http://norc.hu/ (norc.ro) team for OSM.

If so, they're simply Great Heroes.

Vă mulţumesc mult!

Lokasi: Hajdúszoboszló, Hajdúszoboszlói járás, Hajdú-Bihar, North Great Plain, Great Plain and North, Hungary

Anonymus a Hős

Diposkan oleh grin pada 4 November 2010 dalam Hungarian (Magyar)

JOSM tesztelésképp ránéztem „szülőfalumra”, Hajdúszoboszlóra, és láttam, hogy igen katasztrofális állapotban van. Előfordul.

Alaposabban megnézve azonban azt láttam, hogy bár az OSM térképen szinte semmi nincs, valaki gyalog bejárta az egész várost, alaposan, pontosan, szisztematikusan; ebből azonban semmi térképet nem láttam.

Meg tudom valahogy vajon nézni (nyilván HA van a track-hez id adat) hogy ki csinálta? Vajon miért nem rajzolta fel a térképre...?

Másrészt furcsa effektus, hogy SzPaula főútjai mintegy 50m-re vannak a GPS trackektől, szisztematikusan. Higyjek Paulának a GPS ellenében? (Nem tettem, de meggyőzhető vagyok.)

Mindenesetre 'Szoboszló jelentősen jobban néz ki. Elfogyott a türelmem az utcanevekhez, talán majd egy helyi vagány folytatja. (És persze elfáradtam az egymást keresztező utcákban meg vonatsínekben...)

De jó, hogy van róla valami, köszönhetően a Névtelen Hősnek, Aki Bejár.

Lokasi: Hajdúszoboszló, Hajdúszoboszlói járás, Hajdú-Bihar vármegye, Észak-Alföld, Alföld és Észak, Magyarország

tracks

Diposkan oleh grin pada 11 September 2009 dalam English

So I finally exported some GPS tracks and tried to check around. LOTS of white, unmapped areas, some of them unfortunately so much unmapped I cannot even cut the proper roads apart. At least I entered some pivot places to start from. Lazy bastards around Veszprém for example. ;-)

Still no useful aerial of Debrecen, and I have no saved tracks from there. Darn.

On the bright side I've done my first roundabout. Looks ugly. :-(

Welcome

Diposkan oleh grin pada 22 Mei 2008 dalam English

Hmm, well, well, this project has been hiding from me till now. I love the idea. Seems very time consuming waste of time, love it. I have no time, so this may help my struggles to meet universal enlightenment by wasting more time than I have and disappering into Nirvana with a loud *pop*. :-)