### Nerdy Economic Statistics Sunday

Based on a recent conversation, I decided to look closer into Labour Productivity, output produced per unit of labour. My usual go-to site for statistical data on economies is OECD.Stat and as usual, they provided me with the information I was looking for.

In order to nicely visualise GDP per head of population, hours worked per head of population, and GDP per hour worked, I did a brief search for cross-platform data visualisation tools and stumbled onto Orange.
Using this very intuitive tool, I was ale to easily create the diagram I had in mind: A scatter plot of time worked vs. output per head:

This diagram is based on the data for 2013, as it was the most complete dataset with only Australia being an estimate and no gaps. The horizontal axis shows time worked, the vertical axis shows the output, and the size/colour show the productivity.

One of the two extreme outliers is Norway, the place I currently call home. So I looked more into this. One of the first search results was a research paper published by Statistics Norway, the Norwegian statistics bureau, which puts this exposed position into perspective and moves Norway closer to the productivity similar to Germany, USA, or Sweden.
The paper attributes this deviation mainly to the oil and gas income and different possible ways to estimate purchasing power parities.
Another interesting place is France which works very little but at a decent productivity, achieving average GDP per capita. Sounds like a good place, if one values time more than income or things.

A positive note for the countries of low productivity is, that many of them have been leading in productivity growth in the recent years.

Well, enough of this nerdy stuff 🙂

### 12V to USB Charging Converter

After the USB charging converter for my headlight battery packs worked really well last weekend (I got two full charges from one battery pack), I decided to quickly implement a simple 12V to USB charging hack I had in mind for quite some time.

On one of the recent hikes between huts I realised that some of the huts in Norway have solar panel powered 12V power supply. I’ve had a spare car-cigarette-lighter to USB adapter for quite some time and decided to replace the plug with generic crocodile clamps which are more versatile. With these new contacts, I can now attach to any 12V source to recharge USB appliances. For a little protection, I secured the leads with hot glue and covered the circuit board with a bit of yellow shrink tube.

As I’m heading out for a three day snow-shoe hike with friends tomorrow, I quickly hacked an adapter which enables me to charge my phone from my headlight LiPo batteries. This way I don’t need an additional backup for my phone.

In one of my junk-boxes I found a 5.5mm plug which matches the batteries. For the phone end I simply cut some left-over micro-USB cable. I wired it all up with a 5V 500mA Step-Down Voltage Regulator from Pololu and insulated my beautiful soldering job with heaps of hot glue and a silicone cover from an LED strip 😀

### A Bag full of Norwegian Cheese

During the Christmas market in Trondheim, I spontaneously bought a local mountain goat cheese which was especially tasty [Heidrun below]. So I started googling around and discovered a whole network of ecological cheese farms. Many of these apply setring [transhumance/Sennerei], a style of mountain farming which is also common in the Alps. During the summer months the animals, usually milk cows or goats, are moved to a smaller and simpler farm in the mountains. The grass there is rich in herbs and gives the milk and resulting cheese a distinct rich flavour.
Many of these local farms in Norway also offer visits, showing how their produce are made and often also double as bed-and-breakfasts. The network ‘Hanen‘ [the rooster] gives a good overview of the possibilities.

So today I went to the local farmers market, the Bondens marked i Trondheim, a great source for these tasty local cheeses:

1. Heidrun fra Brubekken Gardsmeieri
2. Grote Ost fra Hitra Gårdsmat
3. Blåmann fra Skånaliseter Gårdsysteri

### Saturday on a Sunday @ Antikvariatet

The first thing you see when you enter Antikvariatet is a relatively normal cosy pub. Only when you pass through the hall, which looks like it just leads to the rest-rooms, you’ll discover the back-room which is a very curious blend of library, living-room, and bar. This is where last Sunday’s concert and open-mic night took place.
First Edvardsen & Sønn, a really talented and entertaining duo of father and son (or son an father 😉 ), were playing the Blues. Later, the stage was open to anyone interested. And there were plenty! As each of them only played two or three songs, there was a great variety in styles. For the last songs, the singer got a mix of rather surprised musicians on stage. Together they performed an amazing interpretation of the classic ‘I Shall be Released’ (video below).

### Drone King of the Hill

The recent Hak5 episode 1903 inspired me to build a King of the Hill version for quadcopters. Shannon and Darren talked about their acrylic drone-fighting cage, the last-man-standing matches they had, and their future plans including a version of king of the hill.

Since then, I’ve been working on my own implementation of the king of the hill idea based on an old ADJD-S311 Color Light Sensor Evaluation Board from Sparkfun which I still had lying around. Combined with an Pololu A-Star 32U4 Micro for the brains, a single button for input, and an LPD8806 based RGB-LED-strip from Adafruit for output, this made a pretty nice tinkering project.

The micro quadcopters are split into 2 to 4 teams and are marked with differently coloured stickers at the bottom (red, green, blue, yellow).
The light sensor in the centre of the platform is initially passive and set to maximum sensitivity. In combination with ambient light, the A-Star Micro can detect whether the sensor is covered or not. As soon as it detects that the sensor is covered, it is set to active mode. It then evaluates reflected light using a white LED and a lower sensitivity setting. Based on the measured rgb-colour, ‘the brains’ decide which team the drone on the platform belongs to.
After a team covered the sensor for 3 seconds to win a point, the platform needs to be cleared for 5 seconds before another winning point can be gained.

The game play is set-up using the single button. First the number of teams is shown using the LEDs in the vertical stand. Clicking the button iterates between 2, 3, or 4 teams with different colours. After a long-click, the number of winning points are selected. Again by clicking the button 1, 3, 5, or 7 winning points can be selected. The game starts after another long-click with the progress being displayed on the vertical bar. As only a single LED strip is used, additive colour mixing occurs between the teams. The game continues until one of the teams achieves the necessary number of points, upon which the winning team’s colour flashes along the bar in ‘knight rider’ fashion.

Some friends from FIX, the local maker space, and I ordered a whole bunch of Eachine H8 Mini drones. Now we’re looking forward to some awesome team matches the space 🙂

The CAD models can be found at Onshape, a really interesting web-based CAD solution done by veterans of Solidworks. (log-in and search for ‘Drone King of the Hill’, couldn’t find a public link … still beta 😉 )
The source code can be found on GitHub and relies on the awesome cross-platform code builder and library manager PlatformIO.

### Healthier Soldering

To get rid of the soldering fumes, I re-purposed one of the fans I salvaged from an old office printer:

The fan is hot-glued into a card-board tube which also allows easy positioning of the fume extractor. The flexible tube attached to the end is long enough to reach out of the next window, so no fume filtering is needed.

This makes soldering way more comfortable, and during winter I can fill the window gaps around the exhaust tube with pillows. Smoke-free soldering without freezing! 😀