Week2

Week 2 Progress: System Testing and Redesign Planning II

Over the past two weeks, my main tasks were ordering and testing the required electronic components. The new design uses the Seeed Studio NRF52840 microcontroller, which is significantly smaller—about half the size of the previous Arduino Nano—and comes without pre-soldered headers, improving overall wearability and user comfort.

For motion detection, two flex sensors are used to measure ankle bending angles. A resistor is placed between them to form a voltage divider. To reduce signal noise, an op-amp is included in the circuit as an impedance buffer.

The system is powered by a 3.7V lithium battery, which connects to the microcontroller through a charging module. After initial testing, all components are functioning properly, and full system assembly will begin next week.



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