Quantitative Biosciences Thesis Proposal
Kelimar Diaz Cruz
School of Physics
Advisor: Dr. Daniel I. Goldman, School of Physics
Open to the Community
Title: Undulatory locomotion across scales in heterogeneous environments
Tuesday, September 24th, 2019, 9:00 a.m.
Clough Undergraduate Learning Commons (CULC), Room # 278
Dr. Simon Sponberg; School of Physics, Georgia Tech
Dr. Annalise Paaby; School of Biological Sciences, Georgia Tech
Dr. Joseph R. Mendelson III; School of Biological Sciences, Georgia Tech
Dr. Hang Lu; School of Chemical and Biomolecular Engineering, Georgia Tech
Undulatory locomotion is a form of propulsion present in nature from flagellated microorganisms to slithering animals like snakes (Cohen & Boyle, 2010). Despite the difference in size, slithering animals from mm scale nematodes to meter scale snakes are resistive-force dominated systems, thus inertial effects are small. These animals press lateral body bends against heterogeneities in their surroundings, generating forces necessary to overcome drag on their limbless body. Unlike fluids in macroscopic systems where animals can stop self-deforming their bodies and continue forward motion, in dissipative substrates self-deformation is essential for propulsion. We posit there are common integrative control principles that can go across scales in complex environments. To search for general principles of control in undulatory locomotion we studied the desert-specialist Chionactis occipitalis and the nematode Caenorhabditis elegans traversing lattices of rigid cylindrical posts. Further, we study steering behaviors of C. elegans, capable of maneuvering through complex environments by implementing turns and other strategies. In addition, we consider undulatory locomotors that generate complicated shapes such as generalist snakes. We study the generalist snake Thamnophis saurita, known to inhabit a variety of environments, traversing a lattice composed of movable posts. Finally, we propose an active spring model integrating muscle activation patterns to study undulatory propulsion.