Sensorless Manipulation With Micro Actuator Arrays
Joint work with Bruce Donald,
Robert Mihailovich, and
Noel MacDonald.
We investigate manipulation tasks with arrays of
microelectromechanical structures (MEMS).
We have developed a
model for the mechanics of microactuators and a theory of sensorless,
parallel manipulation,
and we describe efficient algorithms for their evaluation.
Simple actuator control strategies can be used
to uniquely align a part up to symmetry without sensor feedback.
This theory is applicable to a wide range of microactuator arrays.
Our actuators are arrays
of oscillating SCS structures
fabricated in an ICcompatible process.
Sensorless Orientation
The above figure shows a twostep part alignment plan for two different initial
part placements.
In each step the actuators push perpendicularly towards
a straight line. Based on related work on robot grippers [6]
we show that for any part there exists a short sequence of such lines
such that the part gets aligned uniquely up to symmetry.
Sensorless Sorting
In this figure we use a twostep sensorless plan to separate smaller objects
from larger ones.
Recently we have investigated upper and lower bounds on these
strategies [1,5], and we have discovered a
pathological part that cannot be aligned
with such sensorless strategies.
A thorough analysis and dynamic simulation of these strategies
has been performed by
D. Reznik,
Stan Brown, and John Canny at UC Berkeley.
Videos:
Publications:

K.F. Böhringer, B. R. Donald, and N. C. MacDonald,
Upper and Lower Bounds for Programmable Vector Fields
with Applications to MEMS and Vibratory Plate Parts Feeders,
Workshop on Algorithmic Foundations of Robotics (WAFR),
Toulouse, France (July, 1996).

K.F. Böhringer, B. R. Donald, and N. C. MacDonald,
What Programmable Vector Fields Can (and Cannot) Do:
Force Field Algorithms for MEMS and Vibratory Plate Parts Feeders,
IEEE International Conference on Robotics and Automation (ICRA),
Minneapolis, Minnesota (April 1996).

K.F. Böhringer, B. R. Donald, and N. C. MacDonald,
SingleCrystal Silicon Actuator Arrays for Micro Manipulation Tasks,
IEEE Workshop on Micro Electro Mechanical Systems (MEMS),
San Diego, California (February 1996).

K.F. Böhringer, B. R. Donald, R. Mihailovich, and N. C. MacDonald,
Sensorless Manipulation Using Massively Parallel Microfabricated Actuator Arrays,
Proc. IEEE International Conference on Robotics and Automation (ICRA),
San Diego, California (May 1994).
Nominated for Best Conference Paper Award.

K.F. Böhringer, B. R. Donald, R. Mihailovich, and N. C. MacDonald,
A Theory of Manipulation and Control for Microfabricated Actuator Arrays,
Proc. IEEE Workshop on Micro Electro Mechanical Systems (MEMS),
Oiso, Japan (January 1994).
Also of interest:

K. Y. Goldberg,
Orienting Polygonal Parts Without Sensing,
Algorithmica,
10(2/3/4):201225, Springer Verlag (August / September / October 1993).
karl@cs.cornell.edu