Sunday, April 13, 2014

The DARPA Spectrum Challenge is interesting

The DARPA Spectrum Challenge was held last week.  This is an interesting event encouraging innovation in using spectrum much more efficiently.

This is one of those events where it would have been nice to have been there, and talk to some of the people involved in the various entries.

The technologies being developed have huge potential impact for "unlicensed" (really public licensed) spectrum, both existing and future.

Perhaps the biggest outcome was the further validation that cooperating radios can share spectrum, without any central authority or database.  Of course, we already knew that, but this is an extra data point to give regulators courage to make TV white space and other shared spectrum resources available for general use.

Sunday, March 23, 2014

Imitation is the best form of flattery

Recently Jeremy and I attended RightsCon 2014.  Among a variety of good things we were able to do and good people to meet with, we caught up with Miles, who has replicated our Mesh Extenders using the open documentation we have created.  While we know the documentation can always be better, it was pleasing that there was enough information for Miles to be able to replicate our work.  You can see our yellow mesh extender next to the one that Miles built himself.  Hopefully this is the first of many replications of our work.  Thanks again Miles for all your work on this and other things!

Tuesday, March 4, 2014

Low-cost mobile medical devices might just happen

People who know me well know that I have been talking about my desire to commoditise many medical devices by making a mobile-phone based platform that can accept a variety of medical sensors.

The general idea is that the expensive certification can be done once for all on a common hardware platform and core libraries for acquiring, visualising, and storing signals from medical sensors.

This would reduce the cost of developing new medical devices, and allow the same hardware to support many medical devices, driving the cost per function even lower.

I have been thinking for a while about how to get the necessary hardware made, which would have entailed making a custom mobile phone and other complex and expensive things.

However, this all looks much more possible now, thanks to a project that Google have been working on: their Project Ara:

Ara is a modular mobile phone design, where the various parts can be easily replaced.

This would seem to make this concept much easier to make, at least from the hardware side.

Thursday, February 13, 2014

OpenITP UX Sprint ahead of RightsCon 2014

In just a couple of weeks it will be time for 2014 in San Francisco.

In the days just before RightsCon, OpenITP are running a UX sprint that we are participating in.

With the generous support of various organisations and individual supporters Jeremy and I will be attending, and hoping to make some good progress on desktop clients for the Serval Mesh, so that people can make secure VoMP calls, send and receive MeshMS and other files from Linux, MAC OSX or Windows based computers.

Our goal is to make the Serval Mesh much more useful for more people.  Being able to receive data and communications from the mesh on the three major operating systems will obviously be a a big step forward.

So if you are a software developer, technical writer or user experience engineer and in the Bay Area that week, or even if you are not, and would like to help from afar, we would love for you to participate.

Tuesday, November 19, 2013

Don't Panic, it's a Serval Mesh Extender

I have been working on the firmware for the Mesh Extenders the last couple of weeks.

This has involved combining a few features to make a 0.01 release that can go out on the perk Mesh Extenders, as well as some WR703N-based mesh extenders we are preparing for a monastery (more on that in a later post).

I wanted the firmware to support updating of the servald binary and config file, as well as preventing login as root in normal operation, and operating a captive portal so that people connecting to a mesh extender get some idea of what is going on. It also needs to support the different hardware types we are using.

This is all finally coming together as the following image shows.   The captive portal automatically pops up on my Mac if I associate with a mesh extender by Wi-Fi.

I'll talk more about the firmware structure later, and document it on the wiki.  Anyone wanting to take an early look can checkout the source code and look in the somewhat erroneously named mr3020 directory.

But for now, I am happy that we have the main functions of the mesh extender firmware functioning.

Tuesday, November 12, 2013

Open-Source Collapsable Communications Tower

I have been helping some mechanical engineering students from the side-lines with a project to make an open-source rapidly-erectable communications tower, with internal space for comms gear and batteries.

I hadn't caught up with them for a few months, but today was student expo for the department, and so I went down to see what they had created.

It was very pleasing to see a nice that they had indeed managed to make a 6m high tower that can be assembled in less than 10 minutes, and consists entirely of common hardware and a few 3D printable parts, as you can see below:

And again with one of the students who designed it for scale:

The design uses three guy ropes for stabilisation, and was designed to accept an 85m/s static wind load.  The practical limit would be less than that under realistic dynamic wind conditions.

Following my suggestion, the entire tower when broken down is small (<140cm total linear dimensions, approximately 1m in longest direction) and light enough (19kg) that it can be included in checked luggage on a normal commercial flight.

By using only common plumbing components and a few 3D printed components, it could in principle be manufactured (or repaired) in relatively infrastructure deprived settings, provided you had a 3D printer, of course.

Think you'll have trouble finding 3D printer filament?  Then you might want to make use of one of the other student's projects, turning plastic milk bottles into 3D printer filament.  That project has a bit more work to do, but the general concept is there and working.  There are also some other projects around the world working on the same kind of resource scavenging approach.

Thursday, October 17, 2013

Serval recognised in International Red Cross/Crescent World Disasters Report

It is very pleasing to see our partnership with New Zealand Red Cross to enable communications during disasters has been recognised in the International Federation of the Red Cross/Crescent (IFRC) World Disasters Report.

"This collaboration between the New Zealand Red Cross, DeLorme and Serval has created a communications system with many benefits from the complementary capabilities of the three technologies, including the smarts and sensors of the smartphone; the global reach of Iridium; resilient communications due to path diversity and the store and forward mechanism; the value for money of commercial off-the-shelf components; and a familiar interface that can be used before, during and after the disaster."

The full report can be downloaded here: