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I hate unlocking my front door in the dark. I’m never sure if I have the right
key in my hand, if it’s turned the right way, or where the keyhole is. The
worst part is that I have a porch light
right above the door. I can’t unlock
the door without the light, but I can’t get to the light without unlocking the
door. So, the light switch waits for me on the other side of the door, quietly
mocking me. I’ll teach that light to laugh at me.
From now on, porch light, I’m the boss, and these are the rules. You will:
• Turn on at dusk.
• Turn off at midnight.
• Turn on the entryway lights inside the house when someone approaches
the door after dusk but before midnight.
• Turn on both the porch light and the floodlights when someone
approaches the door between midnight and 6 A.M.
For the project to accomplish all this, we’ll need a logic mechanism that can
determine when to turn the lights on and off, and keep track of their state.
The logic mechanism will control the light switch and receive input from
a timer, motion detectors, and conventional light switches. You can buy
or build standalone logic mechanisms, but a computer is the simplest and
least expensive way to control everything. We’ll also need a light switch that
can be remotely controlled by the computer, and a motion detector that can
Automate Your
Porch Light
Cost
Time
Difficulty
$90
three hours
3 out ...