The mechanical structure of this project involves both (1) a case that protects and covers the circuitry, I/O components, and the microcontroller, and (2) an electrochemical cell that gives support to the three electrodes and is where the electrochemical reaction is going to take place. The following sections discuss over the case's external structure and internal structure.

External Structure

In order to better isolate the circuit from unwanted signals and interference, the designed case is all made of aluminium. Furthermore, it features:

  1. an OLED 0.96 inch screen,
  2. an On/Off switch,
  3. an USB-A port,
  4. DIN connector self-made electrochemical cell,
  5. Connector for Screen Printed Electrodes (SPEs).

The figure below shows the schematics and 3D visualization shows the external structure of the case.

image.png

Figure 1: 2D view of an opened bottom-part of the case.

image.png

Figure 2: 2D view of an opened upper-part of the case.

image.png

Figure 3: 3D visualization of both bottom and upper-parts of the case.

Internal Structure

Internally, the case features a space for firmly placing the project circuit board (which also serves as a shield for the ESP32 microcontroller). Also, there are spaces for both batteries to be placed accordingly. The figure below shows the schematics and 3D visualization of the internal structure.