2. The device

2.1. General design

The mechanical structure of the device consists of a box that has two lids on hinges. The box and the top lid are 3D printed. The upper lid has a picture of the schematics of the H bridge as well as indicator LEDs to tell which MOSFETs are currently activated. There is also a small DC motor in the middle of the upper lid. The lower lid is a breadboard with the actual working components wired.

All of the wirings are done on the side of the hinges in order to avoid damage (and also for improved aesthetics). The controls of the device are placed on the side for easier and cleaner wiring. The motor and controls are fitted on a small separate 3D printed part to ensure they fit in the case a replacement part has different dimensions.

The device is powered with a 9 V battery.