Introduction:
In this paper, authors present the development of a completely automated system
to perform 3D micromanipulation and microassembly tasks. The microassembly workstation consists
of a 3 degree-of-freedom (DOF) MM3A® micromanipulator arm attached to a microgripper, two 2
DOF PI® linear micromotion stages, one optical microscope coupled with a CCD image sensor, and two
CMOS cameras for coarse vision.
Methods:
The whole control strategy is subdivided into sequential vision based routines: manipulator
detection and coarse alignment, autofocus and fine alignment of microgripper, target object detection,
and performing the required assembly tasks. A section comparing various objective functions useful in
the autofocusing regime is included.
Results:
The control system is built entirely in the image frame, eliminating the need for system calibration,
hence improving speed of operation. A micromanipulation experiment performing pick-and-place
of a micromesh is illustrated.
Conclusion:
This demonstrates a three-fold reduction in setup and run time for fundamental micromanipulation
tasks, as compared to manual operation. Accuracy, repeatability and reliability of the programmed
system is analyzed.