Shea’s 2 year old son, Alejandro, suffers from spinal muscular atrophy. Alejandro’s symptoms began as an infant, necessitating a special medical stroller. The family’s insurance agreed to pay for the stroller, but as Alejandro has entered toddler-hood, they’ve refused to pay for a wheelchair for another 5 years.
There’s a lot of vital developmental growth that happens during those early years of wobbly, reckless mobility. As Ako describes, “running, bumping into things, pulling clothes out of the laundry basket… that’s all really important stuff for a kid to do, and it happens now.” Ako knew that Alejandro would be missing out in a fundamental way without the ability to move on his own.
So Ako got on Ebay, where he found a used power wheelchair for $800. The wheelchair operated with a joystick, which wouldn’t suit Alejandro, who’s mobility is limited to his toes.
"He has...the same impulses as any other 2 year old, so as soon as he had a way to exercise some of those ... he was off. I’d catch him bumping into walls, on purpose, just to get a rise out of us. It was awesome."
Ako set about hacking the software in the wheelchair, and while exploring options for steering systems, he happened to also attempt a repair on a broken kitchen scale. Taking apart the scale, he got an idea - use the hyper-sensitive load cells from the scale to convert the slight pressure of Alejandro’s toes into a controller.
After building a custom plexi-glass pedal to house the load cells, and gluing on water sandals to hold Alejandro’s feet in place as he steers over bumpy ground, Ako effectively modified the wheelchair’s steering system to allow Alejandro to move himself forward, left, right and backward with subtle movements from his toes.
Ako was amazed, but not surprised, at how fast Alejandro took to the power-chair. “He has all the same impulses as any other 2 year old, so as soon as he had a way to exercise some of those impulses, he was off. I’d catch him bumping into walls, on purpose, just to get a rise out of us. It was awesome.”
Ako has published all of his work on his blog, in the hopes that he might be able to help other parents and children in his situation.
Spinal Muscular Atrophy is a degenerative condition, which means at some point Alejandro may no longer have the ability to move his toes. Ako is already preparing himself for this inevitably by working on EEG devices that could convert Alejandro’s brain waves into a new steering system for the wheelchair and interface with a PC.
Watch the interview:
For a detailed, highly technical description of Shea’s hacking process you can check out his blog here.