Tue 25 Dec 2012
Posted by Marcin
Open Source Ecology is proud to present the Christmas Gift to the World. Our gift this year is demonstrating a major milestone in production efficiency. We have streamlined the production of our open source, automated, compressed earth brick (CEB) press, The Liberator - down to a single day of production - via small-scale, open source, Collaborative Production. The significance is showing extreme efficiency of production on a small scale – by using modular design where a number of parts can be built in parallel with a team of people. The design follows the Open Source Hardware Definition, and we are positioning this development for viral replicability. Computer-aided manufacturing files for computer-controlled cutting and IKEA-style assembly diagrams are now available to the world. With The Liberator, we aim to lower the barriers to widespread use of CEBs in housing construction worldwide. These results indicate that similar efficiency of production can be attained for the rest of the 50 Global Village Construction Set machines. This implies significant economic potential, and is a step closer to the efficient economy - one that bypasses the artificial scarcity created by exclusive rights – and instead focuses on a better and faster development of appropriate technologies.
What is a compressed earth brick press and why is it important?
Production Efficiencies to Date
December 18, 2012 was a historic moment for us at Factor e Farm. We showed a single-day build of The Liberator compressed earth brick press in our off-grid prototyping lab at Factor e Farm:
For this production run – we redesigned the brick machine thoroughly for digital fabrication – via CNC cutting – as opposed to hand-cutting of metal as in all of our previous production runs. The goal in doing this was to reduce the fabrication time to a single day of production. To model the machine prior to CNC cutting – we first did a 1/4 scale model cut via Epilog Mini laser cutter in paper stock – thank yous to NYC Resistor for the help. Since our CNC torch table is not finished yet, we got our full-size parts laser cut from 1/2” thick steel by Cloverdale Manufacturing in Omaha, Nebraska. We then put the machine together like IKEA furniture from these flat cutouts – by combining parts into assemblies and then welding. Because cutting was done via laser cutter – no grinding/finishing was required – with with a precision that allowed novices to put together accurate (+/- 1/16 inch) assemblies – such as the drawer assembly. Because the machine follows module-based design – we were able to have 8 parallel teams work on the build.
Since we built our first prototype of The Liberator four years ago, we’ve been refining the machine and optimizing fabrication to make it the simplest, highest performance, and most replicable, open source compressed earth brick press in the world. The first prototype took a month to build. We have streamlined fabrication to 4 days in September of this year, 2 days in November, and on December 18 – we achieved the one day build.
Results Overview and Highlights
We had a total of 11 people working on the production run. It was a long day…from 8AM to midnight. We completed the frame, drawer, arms, legs, hydraulic cylinder assemblies, shaker motor, solenoid control valve, hopper, and grate. We prepared the Arduino-based microcontroller and sensors ahead of time. We did not mount the drawer tables, shaker, solenoid valve, controller, and sensors in place as we were tired at the end of a very long day. See the machine diagram for reference.
We had significant equipment issues such that literally 50% of the time was wasted. We used 6 welders in total, of which 2 developed shielding gas problems and one had wire feed problems. One may reasonably say that if these difficulties were discounted – it would have taken 8 hours with 11 people to finish the production run. This is still about 88 human hours – much greater than a predicted 25 hour of build time for a highly-optimized process. The long hours are a feature of using unskilled labor, of sub-optimal organization, and of inherent coordination losses of managing a group of people. However, the magic is – because the people work in parallel – a single day still suffices to complete a build. The advantage of this swarming method of Collaborative Production is a socially-sustainable model: a short production sprint with continuous and visible progress until completion of the machine. This is not only satisfying by virtue of the accomplishment – but also fun and even inspiring because of the team atmosphere.
The highlight was exploring the use of flat cutouts from laser cutting of sheet steel – as a means to streamline fabrication. This worked – because precise parts with pre-cut holes allow you to assemble the brick press easily – like IKEA furntiture – because the parts are already made. We took the CAM files:
and got these cut. Then, the build of the machine consisted primarily of welding and bolting the various assemblies together. Modular design meant that many parts were designed as independent modules that were bolted on or otherwise mounted in place. This is a significant departure from before – where non-flat stock such as tubing and angle was cut to size and then holes were measured carefully. Marking and cutting – and especially cutting holes – is time intensive compared to starting with precise flat cutouts – where the only thing left is welding and bolting together.
We prepared IKEA-style assembly diagrams. This is a major step towards producing simple, language-agnostic assembly and fabrication documentation – aimed at increasing the replicability of the brick press.
Replication History and Future Work
6 independent replications of our brick press have been made to date. Our second replicator commented (see http://opensourceecology.org/w/index.php?title=Shuttleworth_Fellowship_2013_Submission#2._Dan_S.-_Second_Replication) -
To my mind, the GVCS Liberator is the single most important technology for global housing anywhere. No machine produces the uniformity and strength of block for the cost as this machine.
This indicates that the potential of The Liberator is beginning to come true. But we still have some way to go. The controller is not yet robust. We are currently upgrading our automated control system to add a pressure switch, and we are shaking the controller/sensor system down for absolute robustness under the roughest environmental conditions.
No related posts.