My second thread here on instructables...
Inspired by the tv-series "the walking dead" I made an apparatus to create Zombie Hands using infrared light and a modified camera.
- A camera which you don't need any longer (or those from your girlfriend or wife ;-))
- IR-LED's (simple 3/5 mm ones and some with more power)
- LM317 (for the voltage control)
- Resistors, capacitors, cable etc.
- wood for the housing
- metal strips
- small aluminum plate for the high-power LED's
- 12V/3A power supply
Step 1: Modifying the Camera
A common camera and her CCD/CMOS-chip is able to "see" not only the visible light but also the near infrared (longer wavelengths up to 1000 nm). But to create sharp Images, the sensor is usually protected by an IR-cut off-filter. It absorbs wavelengths greater than red light. For the Zombie Hands you must remove this filter. Therefore you've to open your cam. This could be more or less difficult, depending the model and of course whether it's your camera or it belonged to your wife ;-)
The filter has a red colour and can be removed easily with a small screwdriver or something else. Then you just have to reassemble the cam, voila.
Step 2: Electronics
LED's need a certain current. If you exceed the Limits, the LED will die earlier or immediately. For this project I use a 12V/3A power supply. With the LM317 you can build a very simply contant current or constant voltage circuit. For the constant current mode you would need powerful and variable resistors with less than 1 Ohm. Because those potentiometers normally can't be bought I decided to use the LM317 as a constant voltage driver.
To increase the efficiency I connected 6 small LED's (with 3 or 5 mm Diameter) in series. For I = 0 mA the entire voltage is f.e. 8V, for I = 100 mA f.e. 10 V. So you've to choose the resistors R1 and R2 to vary the voltage between 8 and 10 V. To make the circuit safer you should add a resistor in series. Five of those 6-packs are soldered parallel.
The small LED's for the fingers totally need 5 x 100 = 500 mA. Each of the eight IR-power-LED's needs 500 mA. I soldered 5 and 3 power-LED's in series. Therefore I have three separate LM317-voltage controllers.
Step 3: The Principle and First Test
The principle for creating Zombie Hands is quite simple. The IR-LED's shine through the Hand and the IR-sensitive camera is able to see that light. Veins absorb that infrared light more than fat and meat and therefore the hand seems to belong a living Zombie...
Step 4: The Result
As I mentioned in the title I was inspired by the series "the Walking dead". I printed some suitable pictures and stucked them with glue on each side of the wooden housing.
Let me say some words to the IR-LED's: The infrared light should only go through the hand and not beside. Stray light would cause extremly overexposure of the cam and you'd see nothing from the veins.
So I decided to make holes in a thick foam and embedded the LED's. This prevents the light from shining not through your fingers.
I hope you like it and maybe you visit my YouTube-channel for further Projects ;-)
Thank's for spending your time :-)