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Applied Math Colloquium

Friday, March 1, 2013, 11:30 AM
Cullimore Lecture Hall, Lecture Hall II
New Jersey Institute of Technology

The neuromechanics of insect locomotion: How cockroaches run fast and stably without much thought

Phill Holmes

Department of Applied and Computational Mathematics, Department of Mechanical and Aerospace Engineering, Princeton Neuroscience Institute, Princeton University

Abstract

I will describe several models for running insects, from an energy-conserving biped, through a muscle-actuated hexapod driven by a neural central pattern generator, to a reduced phase-oscillator model that captures the dynamics of unperturbed gaits and of impulsive perturbations. I will argue that both simple models and large simulations are necessary to understand such complex systems.

The models show that piecewise-holonomic constraints due to intermittent foot contacts confer asymptotic stability on the feedforward system, and leg force sensors modulate motor neurons to mitigate large perturbations. Phase response curves and coupling functions help explain reflexive feedback mechanisms.

The talk will draw on joint work with Einat Fuchs, Robert Full, Raffaele Ghigliazza, Raghu Kukillaya, Josh Proctor, John Schmitt, and Justin Seipel. Research supported by NSF and the J. Insley Blair Pyne Fund of Princeton University.