This undertaking has been delivered as part of my 2nd year module Embedded Systems Project at the University of Leeds.
It was awarded an excellent first degree classification and unsurprisingly became an extremely popular party toy amongst my university friends. Discussing specifics of how the device functionality was validated would not be very professional, but let's just say that it indeed worked as designed.
The objective of this project was to develop a breathalyser device based on a programmable microcontroller chip (ATMega328). This development also included design and manufacture of a custom Printed Circuit Board and fabrication of an enclosure for the whole system cut from acrylic glass material. The breathalyser system was developed to include additional features (such as a Highscore table) and provided a simple and user-friendly interface. I found this to be a particularly valuable exercise in acquiring insight into embedded systems development, not to mention having the most rewarding validation experience of all projects.
Complete block diagram of the system
SolidWorks model of the Breathalyser Design
Printed Circuit Board that was designed in EagleCAD