This machine is a useful alarm for a lot of different things that are important, not just for museum. When someone or something got too close to the thing you are trying not to let anybody touch, this project can be very handy for you.
Step 1: Material
-A ultrasonic sensor
Step 2: The Circuit for the Alarm
Follow the image above then you'll be alright.
Step 3: Writing the Code for Arduino
Below is the link for the code :
Step 4: Making the Container
-Use any container you want, as longs it can show the ultrasonic sensor if it don't it won't work.
-Glue them inside or just put it inside, it's both fine
-Remember to cut a whole for the usb wire