Swarm pico-sat coms tests

We have been doing more tests on the Swarm pico-sat coms with a view to using their system in Iceland.

This graph shows the temperature measurements during 6 days – showing the solar panel charging. On average the modem used 52mA but the battery was providing more like 120mA due to the LEDs and feather board.

Swarm Sat-coms test over a week showing currents
The pass predictor showing the optimum periods for communcation

our first swarm.space network test

Swarm have a system of tiny satellites (11x11x2.8cm) for low data rate communications anywhere on earth. This enables lower cost data access to very remote places.

The Swarm dev kit – the actual unit is the silver rectangular block

In my first test I received my message on their Dashboard within a minute (I was not timing!)

A maximum of 192 bytes can be sent on one message – which is OK for batches of sensor readings. Their cloud (“Hive”) has a RESTful API to gather the data easily. We look forward to building an environmental sensor network test with the help of the Swarm team!

Range testing new systems

In our mountainsensing project we showed that fully standard communications could cover large areas. For that project we had to add an 868MHz transceiver to our designs. This year we are doing a lot of development with the Atmel SAMR30 based system-on-chip as it includes a sub-GHz radio and has good support in the RIOT-OS. One important thing to test was the typical range to make sure it was similar to our roughly 1km with the previous CC1120. Here is a photo of a quick test in the New Forest which achieved 1km with this set of antennas:

image of test node on trig-point

Summary plot for rover3 2018-2019

Here are some screnshots of rover3 on Breida’ – whch we moved in Aug 2019.

So rover3 moved around 12m since we set it up in Sept 2018
and rover3 dropped around 20m in altitude – most of that is due to melting

2019 expedition photos

Prof Jane Hart at Fjallsjökull
Prof. Kirk Martinez
the view over the glacier – near the centre you can see the gps rover
crop from the above photo showing the rover to be in good condition after its winter on the glacier. The normal route we took to get there was cut off so we didn’t visit it at this point.
We carried out an image survey of the area with our quadcopter to produce a 3D model. You can see our dGPS base station in the top right. The Mapir 3 camera uses its own GPS to tag photos – hence the taped on cable and antenna.
Frey controlling the imaging flights with the Tower App – we were lucky to have good weather for our copter-imaging
it takes careful planning of flight areas and a lot of battery changing (we used nine in total)
Fjallsárlón was impressive as usual with ice washed up from ice-falls
Updating a rover on Breida’ – the rovers were physically in good condition after a year on the ice
updating the base station at Breida’ – there are always firmware updates and new ideas to try. It survived the winter very well!
We used an Arctic Land Cruiser in 2019 which made driving close to the glaciers much easier

we moved rover1 higher up and across the glacier – it was very far down the ice after a couple of years.

luckily the equipment is quite light!
our second timelapse camera managed to capture the onset of winter.

Breiðamerkurjökull speeds up in spring 2019

the distance moved by one of the Breiðamerkurjökull nodes shows us the glacier has started moving again – at a rate comparable to the previous autumn. Its also great that this prototype node has sent data so continuously – right through the winter!

Fjalls altitude rise

Fjalls tracker jumped in altitude in March! it is part if its general trend to rise – probably due to the presence of the large ice-cored moraine by the side of the glacier.