This great installation consists out of two parts. A viewing box with replaceable images of a range of different objects like a chicken, a slice of bread and much more. While the visitor is looking at one of these images an eye-tracker within the viewing box records the movement of the eyes.
The second part is the robot, hanging on three ropes from the ceiling on top of a large pile of paper sheets. It reproduces each point the visitor has looked at with a thick marker on the paper by moving the same way as the eyes did.
"There are two Lego NXT (Mindstorm) bricks on this robot, one for the movement and one controlling the pen. Both communicate via bluetooth and are powered by rechargeable batteries, permanently plugged to battery chargers from the ceiling. The process is started as soon a visitor is looking long enough at an image of an object that is inside a viewing box. An eye-tracker records the eye movement into x/y-coordinates. Then this data is saved into a txt-file and sent to the robot via a very long USB-cable. The program on the robot, written in NXC, reads the txt-file and moves to appropriate coordinates."
This results in large scale images showing how the same objects have been seen differently.