Making Furniture Interactive

September 5, 2007

cameleon lamp

Filed under: Exercise 0: Make A Lamp,Greg Saul — gregsaul @ 11:37 am

title image

Concept: To design a light that mimics a color if shown to it. Design: lamp driver. LEDs are very efficient as they only emit one frequency of light, and because of this the light produced could be perceived as flat and lifeless. Instead i used tungsten bulbs because unlike LEDs they aren’t flat and lifeless. Because the Arduino cannot provide enough current to power a tungsten bulb without damaging the Arduino chip, I had to use transistors to turn a separate power source on to power the bulbs. This also meant that the lamp wouldn’t draw too much current from the laptop. To do this i connected the pwm pins to base of the transistors, and grounded the transistors to the Arduino’s ground in series with diodes to prevent current flowing back through the tungsten bulbs from the Arduino. Because i used the pwm pins i could dim the bulbs the same way one can dim LEDs in the Arduino code.colour sensor. Because I wanted the lamp to detect colors and mimic them, I prototyped a simple color sensor. To do this i connected three light dependent resistors (LDR’s) to the analog inputs of the Arduino, with a 10kohm resistor between them and ground to create a light-dependent voltage divider. I covered each of the LDR’s with a piece of red, green, and blue transparent plastic respectively. This meant that when light of a certain color fell on the LDR’s, it would be absorbed and measured differently by each of them, respective to color. Thus, a color value could be interpreted from the LDR’s and replicated with the tungsten bulbs.notes. At the moment, the color sensor only works effectively when a piece of cellophane is held over the sensor to color the light. In further development a lens could be used to focus images onto the color sensor, thus obtaining a more accurate color value.

blue sensorblue lightred sensorred light

circuit layout



  1. beautiful idea. Love it. What did you find out having built it successfully?

    Comment by nthorpe — December 18, 2007 @ 3:04 am | Reply

  2. Very cool. What kind of transistors did you use for this?

    Comment by borgie — January 16, 2008 @ 7:00 pm | Reply

  3. […] Making furniture interactive – The cameleon lamp Link. […]

    Pingback by Making furniture interactive - The cameleon lamp — January 16, 2008 @ 7:13 pm | Reply

  4. […] Because I wanted the lamp to detect colors and mimic them, I prototyped a simple color sensor.Link Posted in : AVR | Arduino | DIY projects | […]

    Pingback by cameleon lamp at Cool Electronic projects blog — January 16, 2008 @ 8:52 pm | Reply

  5. This is great. I have been searching for a good way to hook up external power sources to run leds or your case normal bulbs. Using normal bulbs will be a lot cheaper also! Thanks for the idea! Are you going to post the code?

    Comment by Scorp — January 17, 2008 @ 7:32 am | Reply

  6. […] The cameleon lamp – [Link] […]

    Pingback by Blog » Blog Archive » The cameleon lamp — January 17, 2008 @ 2:37 pm | Reply

  7. […] cameleon lamp « Making Furniture Interactive […]

    Pingback by links for 2008-01-18 « Rob Edwards: Collection of my daily bookmarks: roedward — January 18, 2008 @ 2:18 am | Reply

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