Hi, this is Wayne again with a topic “Four Cable Sand Plotter”.
Hi i’m david bino and i brought to maker faire my poor cable sand plotter, which is this machine right here, uh, basically how it works. Is you got motorized stepper motors hooked up to long lengths of string? You got four strings attached to your carriage and then you can fly that carriage three-dimensionally in space, um, nice, simple machine and basically draws designs and sand. So i built one of these machines once before it was for telus spark science center in calgary alberta. Now that machine was built as a big massive display case, and then i wanted to have one that i could bring to events.
So this machine is designed to all fold up. You can carry it like a briefcase and everyone always gets really jealous, as they have to like pack, everything up in crates and i can just go clunk and then walk out of place with it. So this machine runs off of a beaglebone black running through a probiotic cnc breakout.
Now that breakout just basically isolates the signals so that any noise in the steppers doesn’t blow up the beaglebone and then just running cheap pilolu drivers to basically remove the steppers and keep it going. Whole cost for all. The electronics is under a couple hundred bucks and you could probably build it cheaper too. You go around the fun part to make it all, work is, is it needs linuxcnc and cool thing about linuxcnc is because it’s open source you can hack it. So this case, i’m running a custom, kinematics module to actually do the math and calculate how long each of the four strings should be on the fly. The thing about this machine is: is it kills the productivity of any adult in a 50-foot radius? Doesn’T matter what it’s drawing or what it’s doing, people just want to stare at it.
Now, when i first designed this i’d worked out how to build a full motorized rake system in order to level up the sand at the end of every drawing – and i realized no – that was too complicated. I can just have the thing go back and forth, and people will watch it for hours. How i figured this out was uh. We have a laser cutter at my local hackerspace called protospace, and people will stare at that laser cutter for two hours straight, no problem.
It’S usually just a big crowd, there’s something just magical about watching a machine work, especially when it’s kind of unpredictable, it’s like. What’S it going to do next, .