click da pic for big
Another step forward with our Motion Sensing Intruder Alarm. Today we each added two Light Dependent Resistors (LDRs) to our breadboard prototype. We touched on how computers don't understand analog voltage so it converts the 0-5V signal to whole numbers between 0 - 1023 …and we saw those numbers - representing the light level - coming back to the computer from the Arduino.
We have identified that the 'chatter' level usually reduces during our time together such that we seem to get more productive just as time runs out!
The important question about the safety of electricity came up again so we explored that together. We ranged from lightning through mains electricity, batteries and the signals that travel down our nerves and around our hearts. It's incredible to think that it's all essentially the same thing!
Idea for future project: make a battery!
Next week: program everyone's microcontroller chips then start the migration to more permanent 'stripboard'. After that, start to embed the whole thing in a fancy case (got these already).
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