Noob ? send/receive GPS/Accelerometer data

[mgreene]

We are buying a N900 as soon as they come out with plans to make it a handheld "tracker". What we'd like to do is get the phone's GPS coordinates and accelerometer values and send them (probably via wireless UDP) to a "base" PC which will then display a map with locations of various N900 devices on a test range. How easy is this to do, and what would be the best software to look for in accomplishing this goal?

We'd also like to be able to send messages back to the N900 from the PC base station.

[hopbeat]

I understand that you are aiming into developing your application?

At my uni we are currently developing a context toolbox which will be a c++ library that can be also used for tasks like this.

This way, reading the GPS and accelerometer data will something like 8 lines in c++. Then you can use sockets to send it to the server.

Fairly simple application I would say :)

[mgreene]

Yes, that is is exactly what we're wanting to do - we want to use C++ also!

[mgreene]

What is the SDK/API used to retreive the GPS and Accel values?

[hopbeat]

So stay tuned, we should have the initial version in the beginning of December, which should be more than enough for such task.

Also, you can quite easily do this just out of box (as just reading the data is not exactly rocket science :) ), some useful links:

http://wiki.maemo.org/Accelerometers
http://wiki.maemo.org/Documentation/Maemo_5_Developer_Guide/Using_Connectivity_Components/Using_Location_API

[baksiidaa]

So you just want to transmit position and acceleration data back to a PC? Using an N900 sounds like massive overkill to me.

[hopbeat]

So you just want to transmit position and acceleration data back to a PC? Using an N900 sounds like massive overkill to me.

That's the beauty when company pays :)

(No, no idea why they really want to use N900)

[davost]

Thanks for the pointer on liblocation documentation. Is there python bindings to this API by any chance?

/ David

[mgreene]

Does any one know the resolution of the GPS? My question is that for a demo, we'd like to have several people in a conference area all moving around showing their locations - is the resolution small enough so that they would be separated?

[in-maemo]

Does any one know the resolution of the GPS? My question is that for a demo, we'd like to have several people in a conference area all moving around showing their locations - is the resolution small enough so that they would be separated?

Much much larger than the size of almost every conference room in the world. When I am in my house, the dot showing my current position wanders hundreds of feet. I have as of yet been unsuccessful in seeing the GPS details like which satellites are visible and receiving data, position accuracy, etc (which might reveal that I had a poor solution when the largest wandering occurred). None of the packages I have found are ready for the N900 and/or work.

In any case, accuracy is usually measures in many meters and AFAIK the N900 doesn't have any of the accuracy enhanced features, just basic GPS.

I am also annoyed that it is not using cell phone tower backup like the iphone does. For awhile today it was claiming I was in Spain somewhere.

[TA-t3]

With my Holux M1200 (which I also intend to use with the N900 instead of its built-in GPS) the accuracy seems to be quite good. I have lots of tracks in maemo mapper, from driving hundreds of kilometers. The tracks consistently show which side of the road I'm driving on (from driving one way, then back again). The inaccuracy I see some places are all caused by a fixed sideways error in one direction which only affects satellite images (not maps), for some reason.

With my older, less sensitive etc. GPS I would often see the location jitter all over the place sometimes, particularly inside cities. There's very little of that with the M1200.