Our Weekend Adventure
On Saturday, we visited Karura Forest for Cinema in Nature’s Sounds of Freedom, a guided tour and audio narration tracing the footsteps of the Mau Mau freedom fighters from Kenya’s 1960s independence movement. We hiked through the forest along paths and caves tied to the narration, and ended the journey by painting what “freedom” means to us in a quiet grove.
On Sunday, we went on a safari through Nairobi National Park. We saw herds of zebras, a few hyenas, ostriches, lots of impalas, giraffe families, the rare white rhino, and we even got face-to-face with some lions. I still can’t believe a place like this exists just outside the city, where the skyline can still be seen. (use < / > for gallery)
Back to Work
By Monday, we were back to building our new project: designing an active cast for athletes to help reduce muscle atrophy during recovery.
Our team decided the best approach was to incorporate electrical stimulation, since it seemed to be the best balance between being therapeutic and feasible. But to send out electrical signals to the muscle, we first had to prove we could read them from the muscle.
The EMG Prototype
This week, I worked with Waka (a student engineer at KU and one of the CDIE mentors) to build a prototype electromyogram (EMG), a device that reads voltage changes in a muscle as it contracts.
The challenge? Normal skin is an excellent insulator, which makes signal detection hard. Clinical EMGs typically use adhesive electrode patches and conductive gel to improve signal quality.
But here at KU, we had neither. So we improvised.
We used metal washers wrapped with wire as DIY electrodes. Then, we applied liquid soap to the skin, which contains salts that mimic conductive gel. It seemed a little crazy plugging myself into this makeshift electrical mess, but I had faith in our calculations (and safeguards).
After four days of testing different amplifier circuits, we managed to build a low-cost setup that reads real-time muscle contractions in my arm. Now, muscle strength is just a flick of a switch away.
The Stimulation Circuit
Meanwhile, Saumya and Ellena focused on designing the electrical stimulation circuit. High voltages make it tricky and dangerous to build by hand, so they sourced some of the components online to keep things safe.
While waiting for parts, they also chipped away at the fetoscope project, working on some especially stubborn bugs in the code along the way.
Up Next: Mombasa
After a packed week, we’re ready for a break. We’re heading to Mombasa by train with some friends from Rice (interns at the CCL) to catch a music festival and visit the coast.
(That’ll be us tomorrow →)
Can’t wait to share the stories in the next update.
Signing off,
Jacey Denny
