William Megill, Ph.D.
Biomechanics & Biomimetics Research

Biomechanics

Jellyfish Biomechanics
My PhD thesis research on the structure and dynamic behaviour of jellyfish mesoglea. I measured the mechanical behaviour of jellyfish mesoglea, then developed a model of the fibre-reinforced tissue to predict the behaviour of the mesogleal bell of the jellyfish. This was then coupled with a model of the fluid flow around the animal which correctly predicted the swimming frequency of jellyfish of all sizes. I am currently working on a finite element model of the jellyfish to replace the analytical approximation I developed in my thesis.
Spider Web Design
Research on the dynamic behaviour of spider webs in relation to their mechanical properties. I am using a finite element model to study spider webs made by Golden Orb Weavers. I am looking at the relationship between the mechanical properties of the spiders' silk and the geometry of their webs.
Mechanics of the caudal peduncle in grey whale swimming
I am using an underwater camera and depthsounder to study the straight-line swimming behaviour of grey whales. The animals will often swim parallel to a research vessel, though usually too far away to be seen underwater. Using the depthsounder, which is mounted horizontally on the hull of the research vessel, I hope to be able to "see" the animals at about 50-100', and hence record the deflection of their caudal peduncle as they swim. Field tests of the equipment are scheduled for next summer.
Underwater swimming behaviour of grey whales
We are quantifying the underwater manoeuvrability of grey whales in relation to their prey and the bottom topography. We use suction-cup tags to record the animals' pitch, roll and yaw, while simultaneously recording the depth. The animals are tracked at the surface using shore-based theodolites. The depth and theodolite data are combined to give a picture of the animals' underwater tracks. The body orientation information is then superimposed on the tracks to develop a total picture of the animals' underwater movements. The bottom topography and prey distribution are mapped out using sonar equipment and scuba divers.
Dynamic mechanical behaviour of the human breast
I am using a finite element model to study the deformation of the human breast during running. The model is based on 3-dimensional images of real people, and makes use of literature values for the mechanical properties of the component tissues of the breast and experimental measurements of the mechanical behaviour of the bra fabric. The project is part of a larger study of sports bra design.

Biomimetics

Robo-minnow
A miniature autonomous underwater vehicle, propelled and controlled by conducting polymer technology. The robot swims in a pseudo-tunniform mode using a flexible foil propulsion system. Powered by watch batteries, it is designed to be equipped with chemical and/or light sensors and scrubbers for environmental polutant detection and clean-up.
Biomimetic flagellum
The idea with this project is to develop an autonomous vehicle which can propel itself through very high viscosity fluids. Using conducting polymer actuators, the robot is designed to mimic a biological flagellum, with its 9+2 construction. The robot swims by contracting the actuators in the appropriate sequence to generate a corkscrew motion in the propulsion unit. The robot is essentially a miniature delivery system, powered by watch batteries, and designed to carry sensing equipment into highly viscous environments such as animal guts or crude oil.