Self-Organizing Primitives for Automated Shape Composition
Dr. David E. Breen
September 11, 2008
Carnegie 112, 4:00 p.m. to 5:00 p.m.
Refreshments at 3:30 p.m.
Motivated by the ability of living cells to form into specific
shapes and structures, we present a new approach to shape
modeling based on self-organizing primitives whose behaviors
are based on cell biology and derived via genetic programming.
The key concept of our approach is that local interactions
between the primitives direct them to come together into a
macroscopic shape. The interactions of the primitives, called
Morphogenetic Primitives (MPs), are based on the chemotaxis-driven
aggregation behaviors exhibited by actual living cells. Here,
cells emit a chemical into their environment. Each cell responds
to the stimulus by moving in the direction of the gradient of the
cumulative chemical field detected at its surface. MPs, though,
do not attempt to completely mimic the behavior of real cells.
The chemical fields are explicitly defined as mathematical
functions and are not necessarily physically accurate. The
explicit mathematical form of the chemical field functions are
derived via genetic programming (GP), an evolutionary computing
process that evolves a population of functions. A fitness measure,
based on the shape that emerges from the chemical-field-driven
aggregation, determines which functions will be passed along to
later generations. This talk will describe the cell interactions
of MPs and the GP-based method used to define the chemical field
functions needed to produce user-specified shapes from simple
Dr. David E. Breen is currently an Assistant Professor in the Computer
Science Department of Drexel University. Before coming to Drexel
he held research positions at the California Institute of
Technology, the European Computer-Industry Research Centre, the
Fraunhofer Institute for Computer Graphics, and the Rensselaer
Design Research Center. His research interests include geometric
modeling, scientific visualization, medical image analysis, and
biological simulation. He has authored or co-authored over 70
technical papers, articles and book chapters on these subjects.
He is the co-editor of the book "Cloth Modeling and Animation".
Breen received a BA in Physics from Colgate University in 1982.
He received MS and PhD degrees in Computer and Systems Engineering
from Rensselaer Polytechnic Institute in 1985 and 1993.
Hosted by: Dr. Barb Cutler (x3274)
Last updated: September 3, 2008