An Untethered, Electrostatic, Globaly Controllable MEMS Micro-Robot
(Supplementary Videos)

Dartmouth Computer Science Department

Bruce R. Donald, Christopher G. Levey, Craig D. McGray, Igor Paprotny, and Daniela Rus


We present a steerable, electrostatic, untethered, MEMS micro-robot, with dimensions of 60 µm by 250 µm by 10 µm. This micro-robot is 1 to 2 orders of magnitude smaller in size than previous micro-robotic systems. The device consists of a curved, cantilevered steering arm, mounted on an untethered scratch drive actuator. These two components are fabricated monolithically from the same sheet of conductive polysilicon, and receive a common power and control signal through a capacitive coupling with an underlying electrical grid. All locations on the grid receive the same power and control signal, so that the devices can be operated without knowledge of their position on the substrate and without constraining rails or tethers. Control and power delivery waveforms are broadcast to the device through the capacitive power coupling, and are decoded by the electromechanical response of the device body. Individual control of the component actuators provides two distinct motion gaits (forward motion and turning), which together allow full coverage of a planar workspace (the robot is globally controllable). These MEMS micro-robots demonstrate turning error of less than 3.7 °/mm during forward motion, turn with radii as small as 176 µm, and achieve speeds of over 200 µm/sec, with an average step size of 12 nm. They have been shown to operate open-loop for distances exceeding 35 cm without failure, and can be controlled through teleoperation to navigate complex paths. This document contains movies showing the actuation of the micro-robots during open-loop actuation and teleoperation experiments. The videos have been sped up for ease of viewing. On each video, the time-scale is noted in the lower-right corner of the screen.

These videos are supplementary material for the following paper:

B. R. Donald, C. G. Levey, C. D. McGray, I. Paprotny, and D. Rus, "An Untethered, Electrostatic, Globaly-Controllable MEMS Micro-Robot", Journal of Micro-Electromechanical Systems, In Press, 2005.






Counter-Clockwise Trajectories:
AVI with Indeo
AVI with MPEG4
AVI with DivX
MPEG1
MPEG2


Clockwise Trajectories:
AVI with Indeo
AVI with MPEG4
AVI with DivX
MPEG1
MPEG2


Sample path traversed by one of the micro-robots under teleoperated control.
Traversal of a counter-clockwise rectangular path by turning corners at minimum turning radius.
AVI with Indeo
AVI with MPEG4
AVI with DivX
MPEG1
MPEG2


Sample path traversed by one of the micro-robots under teleoperated control.
Clockwise (rectangular) paths were achieved by looping at the corners.
AVI with Indeo
AVI with MPEG4
AVI with DivX
MPEG1
MPEG2


These videos may not be used for commercial or for-profit purposes.
They are copyrighted by the authors.


This research program is a part of the Institute for Security Technology Studies, supported under Award number 2000-DT-CX-K001 from the U.S. Department of Homeland Security, Science and Technology Directorate. Points of view in this document are those of the authors and do not necessarily represent the official position of the U.S. Department of Homeland Security or the Science and Technology Directorate.

(Revised on 8/25/05)