[FOSS-GPS] High accuracy positioning with low cost GPS devices: a FOSS project

[Eugenio Realini]

Jaykob wrote:
> Hi Eugenio and all the others!
>   

Hi Jakob!

> I'm currently writing my diploma thesis about pretty much the same stuff.
> My aim is to develop a realtime GPS solution for robotic outdoor
> environments with consumer grade single frequency receivers.
>   

We are involved in a project to control a robot for automatically 
drawing painted road markings. This robot should use a low cost receiver 
(AEK-4T) and goGPS as a support for its guidance system. The idea is to 
improve the performance of the AEK-4T by exploiting the observations of 
a double frequency master station (typically a permanent station of 
known coordinates).

> I'm working with two netbooks (eeePCs), one as base station and the other
> one as rover. Communication will be over bluetooth or WLAN so pretty short
> baselines (not much more than 100m) have to be considered.
> I'm aiming for an accuracy of about 50cm. Is that possible with the LEA-4Ts
> and the standard ANN-MS antennas?

Yes it is possible, at least according to our experience. We obtain such 
an accuracy (about 60 cm) by double differencing the rover observations 
with those coming from a permanent station. In particular, any GPS 
station that is able to broadcast raw data in RTCM format can be used as 
a master station by goGPS. In addition, the accuracy can be further 
improved by introducing some constraints like DTMs or known paths.

> Eugenio: Do you publish your thesis and software when you're done?
>   

goGPS is still in an embryonic stage, so we don't feel like distributing 
it for the moment. As soon as a first "stable" version is ready, we will 
publish it on the website and let you know about it. As for my thesis, I 
will publish it for sure after the final dissertation (around this 
spring). Anyway, if you're interested in testing goGPS and sharing 
ideas, you could inform your tutor so that we can organize a meeting 
(even by Skype - in case let me know about it by private email).

bye
Eugenio