The Thymio team has taught the bot how to paint 8-bit-style pictures, by interpreting barcodes. The system largely relies on 39 LEDs and two ground sensors. One ground sensor allows the robot to follow a greyscale line on the ground. The other decodes barcodes. Each barcode sets the robot’s LEDs differently, enabling it to change its color as it moves forward. Each color code consists of 4 bits. The first is always black — to indicate the start a new code. The following three indicate the color value: the first indicates red, the second blue, and the third green. Other colors are created by mixing the three.
To create the 8-bit images, several long paper strips with barcodes and greyscale tracks were laid on the floor with robots on top. A camera set up for long exposures captured the artistic vision.
The Thymio II robots, which also include a pencil holder for drawing, temperature sensors, accelerometers, microphones, and a speaker, can be purchased online from TechyKids for $189.00. Light art instructions can be found on the Thymio Website.