The Giant Printer was originally made in Komponent/LAB, a venue for electronic music and activity (http://komponent.dk/about.php) that Dzl was part of for 10 years. It was made for the Public Service Festival in Copenhagen, Denmark, in 2006. (http://gallery.komponent.dk/albums/PUBLICSERVICE2004/DSCN2476.jpg). At the time, Komponent needed to print some large canvasses, 5 x 2.5 meters and had a limited budget. They needed a cheap printer with cheap ink. When they started to build the printer, their first idea was to build a giant X Y plotter (horizontal and vertical moving bar) but since there was very little time available they wanted to make the printer as simple as possible with as few mechanical parts as possible. They started to experiment and while measuring the length of the belts for the printer, realized they could raise and lower the print head by pulling on the belts. The hardware was simple, but the software proved to be a bit more difficult, they needed to solve the equation for the varying length of each belt as it moved.
After they made it, they were notified that it was similar to the Hektor printer which had been developed during the same time period. (http://www.hektor.ch/) They thought it was great that a common design solution was discovered by both parties, validating their own design choices.
Cue 2010 and 2011. We dug out the printer from storage to make the logo on the side of the illutron barge and then re-imagined it in 2011 for Venture Cup Software Final. Some of the updates included:
- Motors mounted on tripods so it's a portable system
- Machined wooden frame for motor and belt mounts on CNC
- Fresh wires
- Minor software updates
The software takes HPGL plotter file and allows you to scale the image so it fits on the printed area. The software also allows you to pause while printing, in case, for example, you need to refill the paint container. Finally, it also gives you the opportunity to start from where you left in case of fail, such was the case at Venture Cup where our compressor knocked off the USB port each time it started up. Luckily, the software remembered it's last point and was able to continue from there.
The original idea for the printer was a land art printer which could paint buildings, dams, or bridges, painting areas up to 100m x 50m large and the print head would be large enough to accommodate two people and barrels of paint (to fill up the paint container whenever it emptied). Perhaps we'll still pursue that - anyone have buildings that need funky designs?
The next upgrade is to update software so it is less 'wobbly' using acceleration and deceleration rather than abrupt stop and go which is currently employed.
Check out the video of the printer here:http://www.youtube.com/user/GeekPhysical#p/u/3/6C-wn3oKQr0 and the photos here: http://www.flickr.com/photos/29889578@N05/sets/72157625827981787/
The equation describing the lengths of the belts as a function of print head position. A and B are where the belts are anchored and P is the printer head. R0 and R1 indicate length of belts and can be determined by equations given. The length of the belt can be translated into how many steps a stepper motor has to turn by multiplying by a factor of Z.