Thursday 23 April 2015

Real time satellite tracking of your journeys - how does it work?

I'm back in Oslo after my 25 days ski trip across Nordryggen in Norway. It was a great journey, and I would highly recommend doing all or parts of it if you enjoy cross-country skiing. Just be prepared for shifting weather conditions.
The goal of the trip was also to test my solution for real time satellite tracking, explained in several of my previous blog posts. It worked out really well, and people were able to follow along in the comfort of their sofa.

I fastened a Spot Satellite Messenger to the top of my backpack, and left the device in tracking mode while skiing. The device sent my current position every 5 minutes, allowing me to update the map without any mobile coverage. When we arrived at a mountain hut, I pressed the OK button to set up a bed. I also programmed a button to show a snow cave, in case we wouldn't reach a hut. Luckily we didn't have to use it :-)

My map and elevation plot of the 25 days ski trip across Nordryggen. Most of the trip is above tree line, and there are only 5 road crossings in total. 

The SPOT messenger only sends my time and position, so I had to create a web service to retrieve extra information about each location. I'm using a service from the Norwegian Mapping Authority
 to retrieve the altitude, nearest place name and the terrain type. Earlier this winter, I experienced that the service did't return any altitude if I was skiing on lakes, so I'm using the Google Elevation API to avoid gaps in the elevation profile.

By knowing the time and location, I could create an automatic service to obtain more information to enrich the map. In addition to elevation and place name, I've added a weather report.  The image show Bjordalsbu, the highest lying hut on the route 1586 m, which we visited in a strong breeze. 

While skiing, I used Instagram to post photos that would instantly show on the map as well. This required mobile coverage, which is sparse in the mountains. After the trip, I synced my camera photos with my GPS track to be able to show them along the route.

Click "Bilder" in the top menu to see the photos along the route. 

A few of my photos:

Eidsbugarden in Jotunheimen. 

Iungsdalshytta in Skarveimen. 

Taumevatn in Ryfylkeheiane.

Gaukhei in Setesdalsheiane. 

End of trip - and the snow - in Ljosland. 
More photos in my Google+ album.