Sunday, March 6, 2016

Stepper Test

After some modification I was able to get the stepper driver running I had issues at first. So I rechecked my wiring. I also had to reinstall several libraries and modify the code slightly, but now I am moving on to the next stages of creating the machine.


Many years ago I cut a million arrows out of cardboard for a show I was in. I laminated and painted them and was really happy with the results, however the process of cutting them out by hand drove me nuts. The laser cutter seems to be the right tool to expedite the process, not only does it allow me to not have to cut each piece by hand, it also means that I can build up greater thicknesses faster. I won't be pursuing this project for a while, but I do like it and I will come back to it later.

Burn Splint Prototype

After making quite a few rough models the team decided on the strongest versions and went on to make more realized versions of the rough sketches. We used thermoplastic, and torsion springs. We also considered the need to keep the parts that touch the top of the hand non abrasive.

It seems to work well. The finger is extended naturally, and there is still the ability to bend at the second joint. The brace on the palm gives a good deal of leverage, especially when bending the finger. We kept the splint pretty stream lined, you can put the hand in a pocket, but we still need to consider making that easier. The springs work very well, but we also need to make a better interface for them to fit into the splint and hold. The thermoplastic works really well and is very form-able, however it is not perfect. As you work on one part another runs the risk of being deformed. Casting and printing both seem to have potential, but there are limitations to both. The main ones being the resources and know-how needed to do either.

Tiled Pieces

The left over pieces from the larger lattice I cut on the router are interesting.
They are a little plain though. I feel that the contrast was lacking so I bumped it up a bit. I am interested in seeing more of this. Once again the remnants of making something else are now things that I thinking about.

Wednesday, March 2, 2016

Motion Machine

For my motion machine I ordered the main components that I will need for the electronics. I will likely need to add a button and possibly a few other things, but these are the parts that I absolutely need to create the motion. I chose to use a Nema 17 stepper motor for the drive both because I have a very fine range of control if need be, and also because stepper motors have a good amount of torque for their size. The disadvantage of a stepper is that you need a more advanced driver then you do for other types of motors. After looking over my options I chose a version from Sainsmart, not because it was the best, but because it was available on amazon prime. The joke was on me though because it took far longer than two days to show up. Additionally I needed an arduino uno to run everything and a power source.
The next step was to wire everything up and run a test.
Power yes, motion no. Time to trouble shoot.

Tuesday, March 1, 2016

Finger Splints for a Burn Victim

In the latest project for Universal Design we are working to create a splinting device for a burn victim that helps him to keep his fingers straight. The splint needs to be bendable so he can grab things, not be abrasive on the skin on the top of his hands, still allow him to put his fingers in his pockets, and a few other criteria. I am working with a couple of other people to solve this problem, and I think with our varied backgrounds we will be able to create some interesting solutions. Here are a couple of the very rough prototypes that we created.
We created a couple of variations of this one, there is a piece that rests against the palm and helps to keep the last joint straight, the neoprene sleeve keeps the finger straight but still allows the finger to bend. The rigid part in this version is to long and still restricts motion. There also needs to be consideration for breathabilty in the material but there is potential.

Both of these versions allow for the middle joint to move, but help to keep the other joints straight. We found that in this type of prototype the higher the elastic part was attached in the back the better the flexibility and recoil of the brace was.
This best shows the problem with this method. There is a problem with the height in allowing for the hand to enter the pocket. We think that this can be partially alleviated by giving the form a plow shape that helps it to slide into the pocket.

Both of these operate similarly with a rigid bottom piece and straps that could softly hold it to the finger. The main difference being that the top part has an elastic band and the second version has a torsion spring. We are thinking the latter holds a good deal of potential for keeping the entire thing streamlined.

A few of the prototypes we made.

A Few New Things

I am creating new things for my capstone in digital fabrication and design. At this point I am still in the experimentation phase. I still have a million ideas that I would like to work thorough and try, but I think for the time being I will be focusing on patterns and what I can do with them in regards to using the router, laser cutter, and Tormach mill. (Although I did try one additional thing this week)

Same pattern with both the router and the laser cutter. I really like the scale shift, and wonder about making the work piece for the router version even larger.
In the image bottom left I painted the pattern in gloss on a matte background, when I places the larger lattice over it there were some interesting things that happened with the pattern and shadow. Unfortunately with the set up I had I didn't capture any images that really portrayed the contrast.
The shadow by itself looks pretty great though.

When I overlap scale and glossiness interesting things happen and I wonder how that will work with some of the other things I have tried so far.