Harvard’s Kilobots Driven Using Vibration Motors

The School of Engineering and Applied Sciences at Harvard University have created an amazing group of autonomous robots called ‘Kilobots’. The key detail is the robots are able to work together and arrange themselves into complex structures. To position themselves, the robots use two coin vibration motors with an impressive degree of accuracy!

Whilst the Kilobots have been in development for some time, SEAS as released a new video showing 1024 of them making different shapes:

The locomotion looks to work in a similar principle to ‘brisltebots’ which we’ve described before. However, using two vertical coin motors has two advantages:

  • It is now possible to control the direction of the robot, e.g. both motors on = straight-forward, left motor off = turn left, right motor off = turn right
  •  Vertical mounting is necessary for the direction of the vibration force, but it also keeps the footprint low and the unit is not much bigger than the battery 

With bristlebots, the movement is somewhat random, although they tend to turn with the direction of eccentric mass rotation this can easily be affected by the gradient of the surface and the angle of bristles. This makes controlling the positioning extremely difficult, and although the Kilobots will also suffer from these influences (length of legs instead of bristles) the ability to change where the vibration originates can help overcome these variances.

Watching them in a group, you can see why they have been described as a ‘swarm’. To see how the vibration motors enable directional control, this older video has a demonstration (around the 0:48s mark):

Moving the robots is only part of the problem, creating the complex shapes requires a self-assembly algorithm and communication between the Kilobots (achieved through infrared light). If you wanted to make your own, how would you control it?