Medieval Heating System Lives on in Spain

February 8, 2017 by kris de decker Filed Under: Heating appliances, Random

The Meseta Central is a vast plateau in the heart of Spain with long, cold winters and short, scorching summers. The locals say that there’s “nine months of winter” and “three months of hell”. The region has little trees, so heating (and cooling) has always been a challenge.

In the early middle ages, the Castillians developed a subterranean heating system that’s a descendent of the Roman hypocaust: the “gloria”. Due to its slow rate of combustion, the gloria allowed people to use smaller fuels such as hay and twigs instead of firewood. [Read more…]

Rebuilding, Testing and Documenting Self-Made Wi-Fi Antennas

January 29, 2017 by kris de decker Filed Under: Access to information, Communication, Internet, Random

Pretty Fly For A Wi-Fi revisits the histories, origins and uses of self-made Wi-Fi antennas. Many of these designs were once shared through home pages that no longer exist and are now only partially accessible through the Internet Archive. It is a combination of pots and pans, dishes and cans through which people from around the world give shape to their collective dream of making an alternative internet.

This project tries to revive these designs by rebuilding, testing and documenting them. The antennas serve as an interesting point of departure to think about the internet’s infrastructure and how day-to-day users could potentially influence its shape and use.

Most of the antennas result out of the idea of wireless community networks, an idea which emerged shortly after the commercial introduction of Wi-Fi equipment in the early 2000s. These grassroots initiatives aim to build alternative network infrastructures, often on a peer-to-peer basis and without the need for costly wires. Such network infrastructures can be found on rooftops, balconies and windowsills and can cover large distances by broadcasting from building to building.

They are built for a variety of reasons, sometimes to provide broadband connections in areas where there are none, to make censorship free alternatives to the internet or to share the costs of a single internet connection.

More: Roel Roscam Abbing’s website (pictures) & Lídia Pereira’s booklet (drawings, PDF).

Previously: How to Build a Low-tech Internet.

Anti-Surveillance Clothing

January 4, 2017 by kris de decker Filed Under: Clothes, Random

The use of facial recognition software for commercial purposes is becoming more common, but, as Amazon scans faces in its physical shop and Facebook searches photos of users to add tags to, those concerned about their privacy are fighting back.

Berlin-based artist and technologist Adam Harvey aims to overwhelm and confuse these systems by presenting them with thousands of false hits so they can’t tell which faces are real.

The Hyperface project involves printing patterns on to clothing or textiles, which then appear to have eyes, mouths and other features that a computer can interpret as a face.

Read more: Anti-surveillance clothing aims to hide wearers from facial recognition

Human Powered 3D Printer

November 7, 2016 by kris de decker Filed Under: 3D printers, Human power, Random

human-powered-3d-printer

The Trophy is a 3D Print Machine, consisting of an Ultimaker 3D printer and a stationary bicycle to power it. Pierre-Clement Niviere designed it to make people aware of the high energy consumption of printing a 3D-object, criticising a technology that’s usually presented as an environmentally friendly way of production. The set-up also involves the maker in the creation process, raising questions about how 3D printing is changing making.

See it in action. Previously: Mechanical 3D-printer. Thanks to Pim Rooymans.

Pigeon Towers: A Low-tech Alternative to Synthetic Fertilizers

October 25, 2016 by kris de decker Filed Under: Aviation, Farming, Gardening, History, Random

pigeon-towers-iranPhoto credit: Bekleyen, A. (2009). The dovecotes of Diyarbakır: the surviving examples of a fading tradition. The Journal of Architecture, 14(4), 451-464..

Many societies, ancient and contemporary, have innovated ways of supplying their fields with fixed nitrogen and phosphorus—two crucial ingredients for crop productivity. One is crop rotation, which alternates nitrogen-fixing and nitrogen-exhausting crops. Farmers around the world make use of chickens, ducks, and geese to add “fresh” guano to their fields. Cattle manure is another useful alternative—although it often lacks in phosphorus. Much more labor intensive than simply adding fossil-fuel derived synthetic fertilizer, these practices tend to build up soil, limit greenhouse gas emissions, and lead to less run-off into rivers, lakes, and oceans.

Persian pigeon towers are one of the more elegant solutions to the nitrogen-phosphorus problem. These are essentially castles built for thousands of wild pigeons, strategically placed in the middle of the fields. Their droppings were shoveled up once a year and sold to nearby farmers. While most pigeon towers existing today are in disrepair, the oldest still standing are dated to the 16th century (but they are assumed to have existed over 1,000 years ago) and helped fuel the cultivation of Persia’s legendary orchards, melons, and wheat production.[1] [Read more…]

Lamella Roofs

July 15, 2016 by kris de decker Filed Under: Architecture, DIY, Random, Roofs

lamella roof

A lamella roof, also known as the “Zollinger roof” (after Friedrich Zollinger), is a vaulted roof made up of simple, single prefabricated standard segments (mostly in timber) as a way to span large spaces. The individual pieces are joined together with bolts and/or plates to form a rhomboid pattern. Wooden sheathing covers the structure on the outside. The lamella roof was patented in 1910 and became popular between the World Wars, especially in Germany when metal for construction was in short supply. Some of these structures are now almost 100 years old and many of them remain in very good condition.

Read more: Lamella Roof, Open Source Ecology.