A few weeks ago I unboxed and started experimenting with the brand new Xbox Adaptive Controller and its auxiliary 3.5mm headphone jack inputs. Ultimately, my goal is to build a peripheral that my daughter Ellie can use to have an interactive experience on a PC. Ellie has some fairly significant physical and mental limitations, courtesy of her syndrome. But make no mistake, she's plenty feisty, and curious enough that I'm confident we'll be able to figure out something that will at least be a source of amusement for her.
Who fell asleep while mom was holding her in the pool? This girl.
For this project, the name of the game is accessibility. I don't want to do anything overly complicated or that anyone would have a difficult time replicating if they were so inclined. I won't be hitting up my friends with 3D printers to produce parts for me and I won't be spending a lot of money either. Improvisation, creativity, and flexibility are the most important things. I'm adapting a controller to suit Ellie's abilities, not the other way around. It's innovation by way of restriction.
I don't know about you, but the keywords above make me think of a few specific construction materials. PVC pipe and fittings are near the top of the list. Of course, for the actual switch, I needed something slightly more sophisticated than my first proof of concept. I chose something familiar to most gerbils: mechanical keyboard switches. I figure there are dozens of fun ways to actuate keyboard switches and I know they're built to last. I got started by soldering one up to the leads I'd stripped off the audio cable in the previously linked video. Once I confirmed that worked, well, I'll let myself take it from here:
The design in the video is predicated on the fact that Ellie likes to spin things. This is one of her favorite toys. The spinning action that I know she's comfortable with and capable of seemed like a good place to start. The next step was going to be making a rectangular frame large enough for her to fit inside of while laying in her bed. The rollers would have been located where her unique anatomy would be afforded the most leverage on them.
I say "was" because, so far, Ellie does not seem impressed by dad's handywork. I have a couple ideas for making the rollers easier to spin and more interesting to Ellie, though. Even if those ideas don't pan out, I might go through with my original plan anyway, just to see what I learn and to have a completed platform to build on for whatever comes next. Plus, I'm attached to the roller idea because it reminds me more than a little bit of a player piano, or punch card programming, and could lead to "physical macros" where moving and jumping can be rolled into one motion or something along those lines.
The holy trinity of hacking, duct tape, zip ties, and PVC. The threaded insert allows for a bit of calibration.
That said, I'm already thinking of other ways to trigger the switches, especially for her arms. I like the idea of something she could flick up and would hit the switch when it comes down again. One of the nice things about the keyboard switches is that they are so easy to trigger, you don't have to overcome a lot of force. I feel like focusing purely on motion and not leverage is probably a better course, and a flaw of my original concept. Or maybe she'll like it better if I let the rollers move loosely in a channel and treat the switches as speed bumps. I need to run some more tests.