A thousand-robot swarm created by Harvard researchers can self-assemble into different shapes. Harvard roboticists created Kilobots which are small robots that are the size of a penny and traverse themselves by measuring the distance from each other to coordinate and form complex shapes.
With the Kilobots, the algorithm that they use to create shapes are based on a similarly simple set of capabilities:
- Edge-following, where a robot can move along the edge of a group by measuring distances from robots on the edge
- Gradient formation, where a source robot can generate a gradient value message that increments as it propagates through the swarm, giving each robot a geodesic distance from the source
- Localization, where the robots can form a local coordinate system using communication with, and measured distances to, neighbors
The robots talk to each other by bouncing infrared light off of the surface that they operate on. They can tell how far away they are from other robots by measuring how much the brightness of the infrared light changes: the dimmer the light, the farther away they are. But they have no information about where exactly the light is coming from. So, to localize, they depend on an initial “seed” group of robots to define the origin of a coordinate system, and then subsequent robots can localize based on the relative brightness of the infrared pulses coming from at least three other robots that have already been localized.
For details visit: http://www.eecs.harvard.edu/ssr/projects/progSA/kilobot.html