From Jonas Eriksson! (THANKS!)
Dec 18, 2009
Dec 15, 2009
Surface mount LEDs resting delicately on copper wires twined together to create beautiful shimmering LED trees, Arbormorphic - ascribing tree form or attributes to a being or thing not tree.
The trees were inspired from a previous project of Dzl's where he created a much larger version of the tree. We found some Copper wire, first by deconstructing a transformer (pictures coming soon!) and then we finally found our big roll of copper wire and got to work. We pulled a long section of wire across the room, wrapping it around a doorknob at one end of the room and bringing both ends together at the other end of the room, a giant loop. The two loose ends (not on doorknob) were then tied into a screw and using an electric drill we spun it fast and intertwined the two lines of copper.
We then cut the long line of copper into segments, about 30cm long each. We pried apart the two ends of each piece and soldered a surface mount LED on to the end. We tested which sides were positive and negative and then arranged them into a matrix on the protoshield. Below, we describe how and what was done, technically.
Big tree:(White LEDs)
LEDs are connected in a 4X4 matrix on an Arduino shield. These are then connected to 8 pins on the Arduino. The matrix is formed by inserting the LED wires on a proto shield so that the rows and coloumns of the matrix could be run on each side of the board.
Code was quickly written to run through the lights, four at a time and control their individual brightness in 64 levels by multiplexing. A random generator was coded to increase or decrease the brightness of a single random LED. The random generator is run once all the LEDs have been updated.
Little tree: (Green LEDs)
12 LEDs were connected in a charlieplex matrix to control three at once.
The matrix was connected to 4 pins on an ATTINY2313 AVR microcontroller. Code to multiplex the matrix was written to control each LED in 64 steps. The code cycles all LEDs in a sinewave chase with 1/12 phase difference.
Created with Admarket's flickrSLiDR.