Self Calibrating Laser Trip Wire
Intro: Self Calibrating Laser Trip Wire
this is my tutorial on how to make a self calibrating laser trip wire .
WARNING lasers are super bright and will blind you. so don't use them were there are kids or in public spaces!!!
STEP 1: What You Need
- Arduino (any should work)
- 5v buzzer (if you buy one that uses pwm you will have to change the code a little)
- laser (i'm using one from adafruit)
- 10k resistor
- and a photo resistor
STEP 2: Wiring
not a lot to say about the wiring, just copy the diagram
STEP 3: Coding
download and run the arduino code, to program the board
STEP 4: Calibration
the arduino calibrates itself at start up and when you press the reset button.
to calibrate it, align the laser beam up with the sensor like so.
then press the reset being careful not to move the laser or the board.
done, now the system should be armed. you can test it by braking the beam with you hand.
does the buzzer trigger? if so you have correctly set up the system!
STEP 5: Mounting
ounce you have it working you can mount it using blu-tack .
it works best inside or in the dark. it will not work in direct sunlight because it will over power the laser beam giving false readings.
STEP 6: Taking This Project Further
you can take this project further by bouncing the beam around using mirrors to make a massive laser grid.
or reprogramming it to count the number of people walking though,
or even use it for a automatic nerf gun trap!
6 Comments
lieg 8 years ago
can some body put the code what is inside because my computer cant open it pls
WoodsyTECH9 9 years ago
How would the code change for a peizo buzzer?
WoodsyTECH9 9 years ago
How would you change the code to work for a peizo sound speaker?
slattermatter 10 years ago
"it will not work in direct sunlight because it will over power the laser beam giving false readings." - Do you think it would work in direct sunlight if you used a infrared laser with a infrared filter over the photo resistor? Infrared filters block all visible light letting only infrared light pass. This approach will be harder to calibrate but it will be invisible to humans and can be setup outside for surveillance or even a wildlife camera.
wfoster6 10 years ago
you could just mount it in a shadow were the sun cant shine in on it .
but yes it would be possible to use ir although you would have to use a ir sensor
Danger is my middle name 10 years ago
Very cool!