Thomas Bliss pusues his graduate degree while leading this
area of study
on grounds at the University of Virginia.
Central Pattern Generator Control:
Biologically Inspired Neural Control of Tensegrity Structures and Propulsors
The rhythmic movements employed for animal locomotion are ultimately controlled by central pattern generators - systems of neurons connected in such a way that their outputs oscillate in the steady state. It is well known that feedback from the animal's body is essential in regulating the CPG's oscillation profile, allowing the animal to exploit resonance entrainment for efficient locomotion. As such, these controllers have attracted the interest of engineers seeking robust and efficient controllers for autonomous robots.
The aim of this research is to integrate neuronal circuits with tensegrity structures for use in bio-inspired aquatic propulsion. Tensegrity structures are systems of bars held in compression by a network of tensioned cables. The cables in the system act as actuating ``muscles'' as well as position feedback sensors, which can be connected to the output and input of the CPG respectively. The CPG used in our study is the reciprocal inhibition oscillator (or RIO), a two neuron system where the outputs oscillate out of phase in the steady state. Entrainment prediction tools and numerical simulations are used to design a controller for robust entrainment to a tensegrity system, and these methods are validated experimentally on a three cell tensegrity test rig.
Propulsion can be produced by the tensegrity by incorporating a caudal fin. Again, entrainment prediction tools and numerical simulations of the complete system (neural controller / tensegrity system / fluid-fin interaction) are used to design a neural controller capable of entrainment to an efficient propulsive gait. These methods are verified experimentally.