Answering my own question. The robot is based on Kilobot that uses similar locomotion:
"The Kilobots move by controlling two vibrating motors, the same type as you have in your mobile phone and the movement is based on similar micro vibrations. The same principle is used when you leave your phone on a table and the vibrator goes off. The Kilobots actually jump forward, but the jumps are vertically so small that you don't see them leave the table surface. They actually fly for a little while. The robots accurately controlled motion to ensure that the locomotion stays energy efficient, conserving the battery for an extended operating time."
http://m.electronicdesign.com/boards/kilobot-swarms
And:
"Kilobot uses two sealed coin shaped vibration motors for locomotion. When one of these motors is activated, the centripetal forces generated by the vibrating motor are converted to a forward force on the Kilobot located at the motor’s mounting location. The principle of converting the motor vibration to a forward force can be explained using the slip-stick principle…
The slip-stick locomotion of a Kilobot was confirmed using high-speed video of the robot’s movement. Due to the off-center mounting of the two vibration motors, as shown in Fig. 1, the vibration of one motor alone will cause a rotation of the Kilobot about its vertical axis, while the vibration of the other motor will cause an opposite rotation. By controlling the magnitude of vibration for the two motors independently in a differential drive manner, the robot can move in a continuous range from clockwise rotation, to straight forward, to counterclockwise rotation. This enables the Kilobot to move approximately 1 cm/sec and rotate approximately 45 degrees/sec."
http://dash.harvard.edu/bitstream/handle/1/9367001/Rubenstei...
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Answering my own question. The robot is based on Kilobot that uses similar locomotion:
"The Kilobots move by controlling two vibrating motors, the same type as you have in your mobile phone and the movement is based on similar micro vibrations. The same principle is used when you leave your phone on a table and the vibrator goes off. The Kilobots actually jump forward, but the jumps are vertically so small that you don't see them leave the table surface. They actually fly for a little while. The robots accurately controlled motion to ensure that the locomotion stays energy efficient, conserving the battery for an extended operating time." http://m.electronicdesign.com/boards/kilobot-swarms
And:
"Kilobot uses two sealed coin shaped vibration motors for locomotion. When one of these motors is activated, the centripetal forces generated by the vibrating motor are converted to a forward force on the Kilobot located at the motor’s mounting location. The principle of converting the motor vibration to a forward force can be explained using the slip-stick principle… The slip-stick locomotion of a Kilobot was confirmed using high-speed video of the robot’s movement. Due to the off-center mounting of the two vibration motors, as shown in Fig. 1, the vibration of one motor alone will cause a rotation of the Kilobot about its vertical axis, while the vibration of the other motor will cause an opposite rotation. By controlling the magnitude of vibration for the two motors independently in a differential drive manner, the robot can move in a continuous range from clockwise rotation, to straight forward, to counterclockwise rotation. This enables the Kilobot to move approximately 1 cm/sec and rotate approximately 45 degrees/sec." http://dash.harvard.edu/bitstream/handle/1/9367001/Rubenstei...
There's also "Analysis and Experiments on the Force Capabilities of Centripetal-Force-Actuated Microrobotic Platforms" article: https://web.archive.org/web/20121021190224/http://nereus.mec...