Building an earthbag dome

By Bob Wianwright

Earthbag building, also known as superadobe or flexible form rammed earth building, is a newcomer to the sustainable building scene in Australia. The technique has been developed by several architects and builders around the world; well known amongst these is Nader Khalili of Cal-Earth (California Institute of Earth Art and Architecture). Although many load bearing straight walled structures have been successfully built with earthbags, it is in the curved form of domes and vaults that the technique really excels.

The beauty of these shapes, combined with the low embodied energy of this building method and its excellent thermal performance, led us to choose earthbag as an appropriate human scale way to build.

Unlike conventional rammed earth construction, earthbag building is well suited to sites where an ideal soil mix isn’t present, and the grunts and laughter of human labour are able to replace the roar of machinery. The basis of construction is the filling of polypropylene or hessian bags with a moist mix of soil, which is then compressed by ‘tamping’ with hand tools. Barbed wire is included between each row and has a dual purpose; to hold the bags in place while tamping, and to provide additional tensional strength in the wall.

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555 Contest: You've got 8 pins…and one shot.

Rules and Categories

Rules

1. All electronics are fair game (including all flavors of the 555). However, those deemed to not be using the 555 as a major component of their design will be penalized in judging. (i.e. using a microcontroller and only using the 555 for a small part of the application will not be as highly judged as someone using a 555 as the main controller in the design)
2. There are many circuits already out there, but we encourage original circuits AND original application. Don’t copy-paste circuits and don’t copy your peers.
3. You can submit as many times as you’d like but you have to submit separately for each category.
4. Must have sufficient documentation: Choice of video, schematic, images, whatever. You must be able to prove it works somehow and showcase the application. Decision as to whether it works or not is the final discretion of the judges.
5. All rules, categories and decisions are subject to change at any time. We’ll try our best to keep you updated on any decisions that we make and why we make them.
6. All entries must be submitted by March 1st, 2011. Yeah, it’s quick, but the world moves fast, and it’s motivation to get moving!

Categories

Each of the categories will have at least one prize in them, though it is possible that each category can have more than one winner and prize.

 

Art

Use 555’s in a unique way to enhance music, sounds, animation, performances, art pieces, etc.  There will be less focus on unique electrical circuits here and more focus on the inclusion in creative endeavors.

 

Complex/Extreme

The most complex category will include circuits or projects that include the most obfuscated circuits (see an example from Bob Pease here), most overkill (using the most 555′s in a design) or the most ingenious use of the part outside of specifications.

 

Minimalistic

While big and complex is impressive, sometimes the most well designed circuits are the simplest. Since there are so many existing circuits, this category will require the most development for simple circuits and will be those most scrutinized to prevent copying of existing circuits. However, in this category we’ll also be considering the lowest power (minimal power) and the smallest implementation (minimal space).

 

Utility

This category will be application based. 555′s used in the most useful applications spanning energy, test equipment, mathematical computation or fixing a problem in an ingenious way (with a tentative name for a prize known  as the “MacFiver”).

 

Best in show

You do not need to submit for this category. Awards in this category will be chosen from all entries and people winning a best in show category are still eligible for the best in show category. This category will likely have the Forrest Mims prize and the best of Under 18 entries.

An Embedded AER Dynamic Vision Sensor for Low-Latency Pole Balancing

Jorg Conradt, Tobi Delbruck, Matthew Cook

{conradt, tobi, cook}@ini.phys.ethz.ch
Institute of Neuroinformatics, ETH / University Zurich
Winterthurerstrasse 190, CH - 8057 Zürich

Animals by far outperform current technology when reacting to visual stimuli in low processing requirements, demonstrating astonishingly fast reaction times to changes. Current real-time vision based robotic control approaches, in contrast, typically require high computational resources to extract relevant information from sequences of images provided by a video camera. Most of the information contained in consecutive images is redundant, which often turns the vision processing algorithms into a limiting factor in high-speed robot control. As an example, robotic pole balancing with large objects is a well known exercise in current robotics research, but balancing arbitrary small poles (such as a pencil, which is too small for a human to balance) has not yet been achieved due to limitations in vision processing. 

At the Institute of Neuroinformatics we developed an analog silicon retina (http://siliconretina.ini.uzh.ch), which, in contrast to current video cameras, only reports individual events ("spikes") from individual pixels when the illumination changes within the pixel's field of view. Transmitting only the "on" and "off" spike events, instead of transmitting full vision frames, drastically reduces the amount of data processing required to react to environmental changes. This information encoding is directly inspired by the spike based information transfer from the human eye to visual cortex.

In our demonstration, we address the challenging problem of balancing an arbitrary standard pencil, based solely on visual information. A stereo pair of silicon retinas reports vision events caused by the moving pencil, which is standing on its tip on an actuated table. Then our processing algorithm extracts the pencil position and angle without ever using a "full scene" visual representation, but simply by processing only the spikes relevant to the pencil's motion. 

Our system uses neurally inspired hardware and a neurally inspired form of communication to achieve a difficult goal. Thus, it is truly a Neural Information Processing System.

More details in our ISCAS paper or our NIPS poster.

27C3: File - Print - Electronics