The Biggest Technical Problem Yet.
Ahead of me is a solid 2 weeks of prototyping with no presentation and no class. So now is the time to solve the major construction issues and do large bulks of work. Let me first give a detailed branching explanation of my prototyping process. Here is the progression so far:
1. abstract sketches
2. object sketch
3. rough handbuilt first stab
4. rough handbuilt correct sizing
5. laser cut
6. laser cut with gears
For both laser cuts, the machinery is already in place but the program has not been fully coded. I am deliberately stalling on the programming until I am sure about the sizing of the bands, and until an actual keyboard is connected to my breadboard. Right now, my priority is getting this machine to roll in a reliable way.
Prototype 5 (the first laser cut before the midterm) was the first time a full character was realized. The problem I encountered was that the servo motors (by only having a 180 degree range) were not rolling the paper far enough to give me ample drawing space! That is why I moved on to the second version that featured gears. The gears were not a problem to design, cut, and position because of the magic of computers, however the actual acryllic material was too brittle for such abusive collision. Many gears in this prototype crumbled. They crumbled from interacting with other gears, and they crumbled when I was forcing them onto their wooden axels. Unfortunately, our laser cutter cannot do a softer material that is as thick. So the negative outcome for laser cut 2 is that the rollers are rolling very unreliably. However, they give a very desirable rotation range! I was very happy that I at least solved the original problems while I created these new ones.
I am now presented with a series of options. I can go back and redesign the gears, then cut another full object. This would require waiting around for the laser cutting services (7 days). However, I do not like to waste this much time. I can also go back to this latest prototype, and try and reposition the holes and do slight hand-tweaks to the parts in order to make them run better. I realize that doing gears takes people years to learn, and I stumbled upon a pandora's box by introducing those gears in the first place. And that leads me to the third option. I can scrap this dead-end prototype, and go back to the last one and see if I can't make use of the range that I am given.
( 3 days later . . . )
Okay, I am returning to this file instead of making a new entry. I just spent 3 hardcore building days in the lab, and I tried 2 of my options. I hand-tweaked the gear prototype to see if I could not adjust it a bit. It took a lot of custom solution for each of the 12 modules to make them spin in unison without jamming up. I found myself gluing weird things in place, shortening and lengthening rods, re-cutting the wood components to see if I can "get them more precise this time", and similar tasks that do not promise to be useful for next time. Basically, my hand-carpentry is no match for the scale of this computer-generated machine. I think the biggest bug is my clumbsy fingers. So I tried redesigning the whole machine from scratch on the CAD level. While I was sitting there trying to figure out clever ways to avoid all the problems I encountered, I realized that trying to get things this precise was no use unless I could get the ENTIRE machine cut by a computer. The length of these wooden rods make a rather big difference in this machine, and I can't find a way to get them cut as precise as the rest of the model. Is there a way that I can possibly redesign this machine so that building the mechanism does not rely on the work of my clumbsy fingers?
It's apparent how much of a curve ball I've thrown myself.