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time to build something new

I've been making good use of the previous project. It did fail me once (unfortunately, that moment was probably the most necessary situation for the project..), but overall, it has been serving me well.

Ever since, I've been constantly thinking about what project I should start on next (or rather if I should even start on something else), but I never really got to thinking up an idea that is useful, not too time consuming, and relatively fun. It took some outside factors to get me started on a new project.

A couple of weeks ago, I was approached by a friend in church who wanted advice for a project she has to work on. It was an industrial design project in nature but required electronic functionality. As soon as I heard the general specifications, it spoke "I could be done with an Arduino." I decided it would be a win-win situation to help out by implementing the electronic part, as it is my understanding that the main focus of her project--what's graded--is the design/implementation and not the building of what goes in it (that are not related to design).

Basically, the project is about a key container that, when activated, would lock a key inside and will only open after a breathalizer check that returns a legal BAC (blood-alcohol content) level for driving.

So far, the requirements I have understood for the electronics is:

- a breathalizer component that measures BAC
- a simple LED display that displays the BAC
- a locking device that controls lock/unlock electronically
- an on/off button

 I've searched for available instructions on building a DIY breathalizer, and this Instructables entry seems to provide me with a good start.

Currently, my idea for the implementations for these components is:

- a circuit built around the MQ-3 Alcohol Gas Sensor for the breathalizer 
- a 4-digit 7-segment display
- no idea on locking device yet
- any kind of latching switch 

I've already ordered the alcohol sensor, will have to start ordering the other parts.

Let's start a new project!

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