side by side.
members on and
off, plug itself in to
recharge or receive
start, pause, or
stop the program
without any human
collective as a whole, the robots have a single overhead
infrared controller that transmits infrared messages to the
collective. That controller is commanded by the operator
from a computer.
To power the robot on and off, it has a sleep mode for
off instead of a battery disconnection, and it can power on
again after one minute. The microprocessor then wakes up
and turns on its infrared communications. The overhead
controller sends a wakeup message every 3 ms to tell the
robot to wake up the rest of the way. The overhead
controller can also switch the robot back to sleep mode.
The robots can remain in sleep mode for up to three
months on a single battery charge. The whole collective can
be turned on in under a minute using the overhead
The roboticists charge the collective by pushing them
all simultaneously onto a conductive surface with a stick. A
conducting board is placed on top of the robots. The
appropriate voltage is applied to the bottom conductive
surface and the top conducting board which connects the
input of all the robot’s chargers to the given voltage. The
whole process can be completed while addressing the
robots as a whole rather than one by one.
The robots are collectively programmed by transmitting
a jump to a bootloader message from the
overhead controller which — when received by
the main program code — causes the program
counter to move to the bootloader section of
the code, executing the bootloader program.
This way, all the robots in the collective are
programmed in under a minute.
while remaining in their environment, communicate to and
measure the distance to their robot neighbors, and to run a
controller unit. The first activity to demonstrate these
functions is one in which the robot orbits or traces a circle
around another robot which then functions as the center of
the orbit or circle.
The stationary robot sends a message at one-tenth of a
second intervals and the orbiting robot receives them to
maintain constant awareness of where the center of the
orbit or circle is. Using these distance communications, the
orbiting robot’s controller calculates when the robot
deviates from the orbit so that — using a PD controller — it
can adjust motor intensity to correct its course.
In another demo, a Kilobot followed a complicated
path; a U shaped path to be exact. To set up this
demonstration, three Kilobots form a triangle and know
their own positions. They communicate that position to the
moving Kilobot 10 times per second. The moving robot
uses those positions and its distance to those positions to
determine its position in the U shape that it must follow.
The robot must move from inside the first robot to outside
the second one, and back inside the third one to complete
the U shaped path.
The Kilobot collective can power itself and its
Aerial view of the maze.
As small as the Kilobot collective is, it
accomplishes much in taking swarm robotics
to the next phase: scalability. SV
Michael Rubenstein, Kilobots creator
More images of Kilobots
12 SERVO 10.2011