Perfboard design

For the prototype model, we decided to use perf boards instead of PCB boards for time and accessibility purposes. There were two perf boards designed and constructed - one supporting the Arduino Nano and its associated I/Os, and a second one for the buck converter and fuse which connects to the battery.

For design, the components and wiring were pre-established through our breadboarding tests. Terminal blocks were used for all I/Os to allow for easy removability during testing. However, while helpful for prototyping, they needed to be strategically placed as they are comparatively large. The two sides of the Arduino were bridged through ground and 5V. The left side of the Arduino perf board contains all of the digital inputs required: 2 LEDs, 3 buttons, 3 motor control inputs, and 2 limit switches. The right side contains the analog pins - 3 pressure sensors and a battery voltage reading, and supports the power connections from the battery board.

Figure: Arduino perfboard

The battery perf board had relatively fewer components. Its main purpose is to connect to the battery. This adds an additional safety layer because the board contains a fuse to prevent large amounts of current. This board also contains a voltage reading circuit, power to the motor (12V), and a buck converter that powers the Arduino (8V) from the battery.

Figure: Buck Converter Perfboard