What Am I Doing?
Customize products for impaired patients.
MORE DETAILS
We would have patients stop by and explain their issue with a device they use. The issue typically involves an inability to interact with the interface. Our goal was to circumvent the issue with either add-ons or modifications to the device.
What was I thinking?
I’ve always wanted to help in a medical setting through fabricating.
The Assistive Technologies Lab was the place for me.
MORE DETAILS (context)
There’s not much more to add. I enjoy prototyping. I’ve always thought of providing assistance through prototyping. The Assistive Technology Lab was literally the perfect place to do such.
What I made?
SMALL PROJECTS (no images)
- LED case for showing wheelchair modes.
- Add physical guide to keep fingers on a trumpet finger button
BIG PROJECTS
USB-MOUSE CONTROLS A WHEELCHAIR
I do not remember what the reason was for prototyping this idea; it might have been one of those moments thinking: “what if”.
MORE DETAILS
The electronics were fairly simple: an Arduino with the USB shield, used for translation of USB signal to analog, and an analog reference voltage (which is typically provided by missing joystick/controller itself). The actual USB translation was pretty straightforward. Per usual, you had case scenarios that needed to be individually discovered (through using-based debugging), and remedied.
Let’s talk about some issues. The two issues were lag times and keeping a stable reference voltage.
The reference voltage seemed to sway with little direct correlation to one specific action. The reference voltage was simple, created using a resistor voltage reduction, which made the troubleshooting hard to execute. I suspect the voltage source, originating from the wheelchair swayed when operating.
After debugging, the lag times were determined to be also associated with voltage source sways.
All in all, stable prototype with one specific issue.
ONE-HANDED WII CONTROLLER
We had a patient come in with an inability to use one of his hands, and wanted to play his PS2. After brainstorming, we decided to integrate the Wii nunchuck into the main Wii controller. The resulting product would be a one-handed controller. Also, we used a translator to convert the Wii controller signals to PS2 controller signals, which was the Cronos translator
MORE DETAILS
The design process was fairly straightforward, with some hiccups. The model was fairly standard to make. However, it was tricky when defining the curved surfaces of a wii controller (it is not a simple elliptoid). Also, I unexpectedly had to fine tune the button dimensions, to create a nice tactile feedback. It was surprisingly difficult, taking lots of iterations. The electrical configuration was simple as well. All I had to do was physically accommodate some PCBs into the main Wii controller, being conscious of possible short circuits. There was literally just enough space for the accomodation. Replicating the assembly process was relatively simple; intermediate makers could replicate such a build. Lastly, the materials needed are relatively cheap; the entire bill of materials is definitely cheap, an estimate of $100.
There were a couple hiccups. For example, the downside with using SLS prints is that the curating process never truly stopped and caused noticeable deformations, so much that the print was close to unfunctional, after a month or so. There was a frustrating inconsistency with the lag from IR readings to the PS2. The goal was to play COD; however, it would sometimes lag. The interface provided by Cronos was fairly high-level and hard to pinpoint the source of lag.
Ultimately, I had success with the prototype, in a controlled setting (my room), but it ultimately didn’t fare well with the patient. We encountered an unexpected issue with connecting the modified controller to his fairly old PS2. I provided some work around involving a soft-mod and adding driver support for Bluetooth controllers; apparently, bluetooth was only supported on PS3 and higher.
Did I help?
Yes!
Most patients liked the customizations. (Felt good)
I felt like I influenced the forming of the lab’s direction.
The Lab was fairly new.
I done did good. (pat on the back)
MORE DETAILS (explanations)
I felt like I had an impact on the lab’s direction. The lab was starting to expand, and I was their first, new intern. I think my experience was used as a first look into practical prototyping, as means of assistance. The lab started expanding their fabrication methods. Unfortunately, that was toward the later part of my time there, but I am glad I had an influence on their decision to expand their prototyping capabilities.
Last I heard, they got multiple types of 3d printers (SLA, fiber composites, larger FDM printers), more machining equipment, PCB makers, and new software. That sounds exciting. I know for a fact, any college graduate or a capable, enthusiastic maker would find that spot exciting.
Big thanks to Melissa Oliver, Brian Burkhardt, and Seth Hills at the Assistive Technology Lab (Hunter Holmes McGuire VA Medical Center) for providing the opportunity. Those three are a great team.