Biomedical Engineering Reference
In-Depth Information
7
Conclusions
and Future Work
7.1 Book Contributions
This topic has presented advanced optimization techniques for automated
synthesis, testing, and pin-constrained biochip design. In contrast to previ-
ous conceptual methods, the described techniques address practical issues
that arise in the design, fabrication, and use and maintenance of digital
microfluidic biochips. By bridging the gaps between theory and realistic
applications, these techniques provide powerful, practical, and fully auto-
mated design tools for digital microfluidics.
Droplet routing and defect-tolerance issues have been considered during
chip synthesis, and we have presented a defect-tolerant, routing-aware, par-
allel recombinative simulated annealing (PRSA)-based synthesis method.
Droplet routability, defined as the ease with which droplet pathways can
be determined, has been estimated and integrated in the synthesis flow.
The method increases the likelihood that feasible droplet pathways can be
found for area-constrained biochip layouts. The synthesis tool also imple-
ments anticipatory defect tolerance to guarantee system robustness for the
synthesized design.
To reduce fabrication cost, we have presented three techniques for
pin-constrained biochip design. The droplet-trace-based array-partitioning
method utilizes the concept of droplet trace, which is extracted from the
scheduling and droplet-routing results produced by a synthesis tool. An
efficient “Connect-5” pin-assignment scheme has also been developed and
combined with the array-partitioning algorithm to control a large number
of electrodes with a small number of control pins. Another pin-constrained
method is based on a “cross-referencing” addressing structure that uses
“rows” and “columns” to access electrodes in digital microfluidic arrays.
A clique-partitioning-based droplet manipulation algorithm has been pre-
sented for the “cross-referencing” biochip, which allows simultaneous move-
ment of a large number of droplets. A broadcast-addressing method has been
presented. The concept of “don't-care” status in the control of electrodes
has also been introduced for the first time. By combining “compatible”
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