A bio-inspired undulating aquatic propulsion system | René Sonntag | Research

Field | Discipline

Biomimetics

Summary

In the context of bio-inspired aquatic propulsion, the aim of this PhD project is to develop a simple fish-like undulating propulsion system that is efficient, robust and easy to build. It should be applicable to small AUVs and also usable for educational purposes, e.g. to simulate undulatory swimming realistically with low cost models in a flow tank.

For this reason, the kinematics and two dimensional flow patterns of rainbow trout swimming in a flow tank were analysed in detail, using a high speed camera and particle image velocimetry. The analyses results provide the reference values that should be reproduced by severely simplified fish models. The “fish body” of these models was reduced to simple rectangular foils with the same aspect ratio (total length to height) as rainbow trout. The models were made of a carbon fibre / resin composite and showed different, successively tuned stiffness characteristics. They were driven by an oscillating rod and the only pre-set parameters were driving frequency and lateral deflection angle. The models kinematics developed exclusively passive by model-water interaction and, in the most promising configuration, matched the reference values of trout to a high degree. Force measurements, additionally, disclosed its potential for micro-AUV propulsion.

Furthermore, some models showed fish-like 2D flow patterns and were suitable for complex three dimensional fluid dynamics analyses and dynamic 3D flow pattern visualisation. In combination the tested models revealed interesting insights in to the dependencies of kinematics, flow patterns and thrust on the models stiffness characteristics and hence, are very promising for the application as AUV-propulsion system or educational test models.

Supervision by

Promotor: Dr. E.J. (Eize) Stamhuis, Biomimetics | ESRIG, University of Groningen
Co-promotor: Prof. dr. A.B. (Antonia B.) Kesel, Faculty of Nature and Engineering, Biomimetics Innovation Centre (B-I-C), City University of Applied Sciences Bremen, Germany

More information and contact details:
Hochschule Bremen - City University of Applied Sciences
Bionik-Innovations-Centrum B-I-C
Hermann-Köhl-Str. 1 28199 Bremen Germany

Postanschrift:
Neustadtswall 30, 28199 Bremen

Phone: +49 421 5905 2595
Fax: +49 421 5905 2537
Email: rsonntag bionik.hs-bremen.de