Sunday, August 14, 2011

we're talkin' 'bout (soldering) practice

I made a quick trip up to Atlanta this week, but now I'm back in Gainesville. One more week until fall term begins. This year, my TA position will be assisting with Theory 3. I've heard it's a heavy workload, but I'm looking forward to gaining more teaching experience.

I have been working on soldering together Tether 2.0. The circuits on the last version were done on breadboards, so I wanted something more permanent. I bought some perfboards and started soldering components. This is a learning process to be sure!

I royally messed up the first board - got solder everywhere. A lot of this was due to workspace - I was soldering on some wood on the ground and couldn't really see that well I think. I moved everything to my desk and turned on all the lights (during the day as well!) and could do a lot better. However, the second board doesn't seem to function. I'm not sure why, so I think I'm going to need a voltage meter to diagnose it. Solder wick, clamp or "helping hands," and wire snippers are in my future as well.

Worst comes to worse, we can stick with breadboards, maybe with some hot glue for quality assurance, but I really want to say "I can solder" and not be kind-of lying.

If you want to learn how to solder, I recommend these videos: Perfboard Prototyping and How to Solder.

Monday, August 1, 2011

Tether 2.0

Artist Josh Cajinarobleto and I are working on refining our "Tether" project, which you can read about in previous posts (March-April timeframe). It's been really nice to have the luxury of TIME. Each week we seem to have another mini-breakthrough.

In Tether 1.0, we measured distance by having our spools of tether line push a button repeatedly. This worked for moving apart, but we needed to push a switch and hand crank the spool when moving closer together. While the handcranking arguably adds an interesting element to the performance, we are attempting to do without it this time.

During our reseearch, we learned about Constant Force Springs, such as those used in tape measures and other retractable gadgets. Interestingly, it was cheaper to just hack some tape measures instead of buying just the springs. So that is the inner mechanism now. We will be attaching cable to the spring instead of the steel tape.

Later I learned about Rotary Encoders, which are perfect for our purposes, as they are made to count turns in both directions. Due to the mold of the plastic for the tape measure/cable spool, we won't be able to attach the encoders directly to the cable spool, so we will be cutting one side of the spool into a gear shape, and making a separate gear that will drive the encoder. Fortunately, someone made an interactive design program accessible online [here].

Once this hardware is done and I've revamped the program, we'll move on to the enclosure design. Since the contraption is much smaller this time, we're hoping to make the grotesque organs that encase the electronics a little better-fitting and less unwieldy (more wieldy?) We may be working with some dancers in the future, so all these improvements will be helpful - they should just be able to wear them, flip an "on" switch, do their thing, and the electronics will react. More info soon!