Droplet

Overview

A ping-pong-ball-sized swarm robot built at Nikolaus Correll's lab at CU Boulder, meant to sit between the Kilobot and e-puck in size, cost and ability. Each Droplet uses six infrared emitters and receivers both to send messages and to work out the range, bearing and heading of neighbors from a 6×6 grid of signal strengths, so one broadcasting robot gives position information to every robot that hears it. Groups share the infrared channel with time slots, keeping in step with a firefly-style synchronization rule, and have been used to form shapes, camouflage themselves against a projected pattern and act as atoms in a chemistry simulation. The robots never need charging because their legs draw power from a striped electrified floor, and they can be poured out of a bucket and right themselves. The catch is that the whole system depends on that special floor, the robots were never sold, and the code and tools have not been updated since 2018.