building an ambient light for the screen:
The CuVoodoo ScreenLight mimics the Philips ambient lighting. The idea is to have LEDs on the back of the screen, lighting on the sides the same color as the border on the screen, creating an ambient light.
To implement this I used: VLC (with the AtmoLight video filter) or boblight (way better) to output over serial the colors to be shown on the LEDs; an Atmel ATmega328P microcontroller at 16 MHz (i.e. Arduino Nano 3.0) to control the LEDs and show the values received over serial; a strips of WS2812B chained LEDs (i.e. BlinkyTape), individually controlled using a data line.
building an electronic cat repeller to guard the fridge:
My sneaky cat can open all doors, even the fridge door. No meat is safe any more.
To prevent that I built a cat repeller using an Atmel ATmega328P Arduino Nano 3.0 board.
An HC-SR501 PIR motion detector checks if the cat is nearby. Then an E18-D80NK range detector verifies if the cat is in front of the fridge.
If this is the case a ~24 kHz PWM signal will generate an ultrasound using a piezoelectric diaphragm, encouraging the cat to leave the premisses.
If it still opens the fridge, a human audible alarm will sound until it is closed.