AML Talk
MICRON - An Active Hand-held Instrument for Enhanced Microsurgical Accuracy
Wei Tech Ang
This talk presents the first prototype of an active hand-held instrument to
sense and compensate physiological tremor and other unwanted movement during
vitreoretinal microsurgery. The instrument incorporates six inertial
sensors (three accelerometers and three rate gyros) to detect motion of the
handle. The movement of the instrument tip in three dimensions is then
obtained using appropriate kinematic calculations. The motion captured is
processed to discriminate between desired and undesired components of
motion. Tremor canceling will be implemented via the weighted-frequency
Fourier linear combiner (WFLC) algorithm, and compensation of non-tremorous
erroneous motion via an experimental neural-network technique. The
instrument tip is attached to a three-degree-of-freedom parallel
manipulator, actuated by three piezoelectric stacks. The actuators move the
tool tip in opposition to the motion of the tremor or other erroneous
motion, thereby suppressing the error. Experimental results show that the
prototype is able to follow one-dimensional and three-dimensional
trajectories with rms error of 2.5 mm and 11.2 mm respectively.
Last modified: Thu Oct 5 10:29:09 EDT 2000