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AcuDo

AcuDo is an electroacupuncture system designed to non-invasively measure electrical skin resistance. This project is based on Dr. Yoshio Nakatani's theory of Ryodoraku acupuncture.

The system consists of two main components: hardware and software. The hardware is a wireless resistance measurement device that adheres to the requirements of Nakatani's theory, such as operating at 12.6V. The software includes a client-side mobile application and a backend service. The mobile app receives measurement data from the hardware and sends it to the backend, which processes the data and generates reports.

Technologies

Story

This project stands out because it involves both hardware and software development. Here are some highlights from the development process:

Initial Prototyping

Initially, I experimented with different approaches for the hardware component. One of the early prototypes was built using an Arduino Pro Mini with a small OLED display to show current measurement values. However, this version lacked battery charging and wireless data transfer capabilities.

Device made with Arduino Pro Mini

Battery Charging Circuit

Next, I explored various solutions for safe battery charging circuits. Below is a photo of one of the test boards used during this phase:

Charger board with battery

Bluetooth Integration

The subsequent step was enabling data transfer from the hardware to the application via Bluetooth. This required building another PCB:

Assembled board with Bluetooth module and charger


Manufacturing process photos

Portability Enhancements

To enhance portability, I developed a board that integrates all necessary components onto a single PCB. This version can be turned on/off with a button and features a micro USB charging port on the side. Here are some images from the development process:

Photos of the first portable version board, model render, and assembly

Final Design

After verifying the device's functionality, I commissioned a metal case to evaluate its appearance and feel in a production-grade enclose. Although costly for small quantities, the precision manufacturing required for the power button and USB connector holes resulted in a superior product compared to earlier versions.

Device in factory-quality case

To simplify manufacturing, I relocated the charging port to the end face of the device, eliminating the need for precise hole placement in the metal case. Additionally, I implemented a touch-based activation method, removing the hardware button entirely and streamlining the design and assembly process.

The final variant of the device. Diameter: 12.7 mm (1/2 inch), Length 135 mm (~5.3 inches).

Results

Through this project, I gained extensive experience in developing a hardware device from concept to completion, creating firmware, and transferring data to a mobile application. I also learned how to develop cross-platform mobile application and navigate the iOS App Store review process.

Mobile Application UI screenshots

Link to Project

https://acudo.site