This was a project for Principles and Practices of Assistive Technology (PPAT) in Fall 2016 at MIT. We made a motorized wheelchair controller mount for our client, Lisa. She lives at the Boston Home, a center for people with progressive neurological diseases, and has Multiple Sclerosis.
With her old controller mount, she would often bump into sinks and tables because the controller was difficult to push out of the way and jutted out, preventing her from getting as close as she wanted. She wanted a method to move the mount out of the way easily so that she could access sinks and tables. Our solution was to create a motorized controller mount, which uses a DC Gear Motor and a microcontroller (Arduino UNO) so that Lisa can move the mount with the push of a button. One button press moves the mount away from her, and another press moves it back in front of her.
We understand that this is not just a problem face by Lisa alone. A large number of powered wheelchair users face this and similar problems all over the world. Hence, we created this instructable with open sourced designs for anyone who wants to replicate the project. You can find all the relevant documentation for this project on the Wiki page, including code and design files. In this instructable we will try to show you the steps for creating the same.
According to Lisa, "it works just like I'd imagined."
You can watch a video of our device in action here
Authors: Suma Anand, Abhinav Gandhi, Nora Kelsall, Mark Vrablic
We ensured that the parts used for our prototype were common and easily available. Here is a comprehensive list of all the parts with their specifications. We have also added online links wherever possible.
1” Aluminum 6061 Extruded Bar stock
Scrap piece of steel sheet metal 1.1 - 1.2mm thick
Cytron 12V 17RPM 194.4oz-in Spur Gearmotor
Motor mount bracket
Screws and nuts - multiple sizes
set screw: 8-32 size and thread
Heavy duty limit switch
Arduino UNO(we used this as we had one lying around. You can use a smaller board such as arduino nano if you like)
L293D motor driver IC
LM2596 buck converter IC
LM7805 voltage regulator IC