Computational Approaches for Modeling Power Consumption on an Underwater Flapping Fin Propulsion System

TL;DR

This paper develops computational models and a non-dimensional figure of merit to evaluate and optimize the propulsive efficiency of bio-inspired underwater fin systems, aiding in design and control improvements.

Contribution

It introduces a novel figure of merit for assessing fin efficiency and uses computational models to compare fin materials and gaits for underwater propulsion.

Findings

FOM effectively evaluates propulsive efficiency across fin designs.

Material choice significantly impacts thrust and efficiency.

Models predict performance under various operating conditions.

Abstract

The last few decades have led to the rise of research focused on propulsion and control systems for bio-inspired unmanned underwater vehicles (UUVs), which provide more maneuverable alternatives to traditional UUVs in underwater missions. Propulsive efficiency is of utmost importance for flapping-fin UUVs in order to extend their range and endurance for essential operations. To optimize for different gait performance metrics, we develop a non-dimensional figure of merit (FOM), derived from measures of propulsive efficiency, that is able to evaluate different fin designs and kinematics, and allow for comparison with other bio-inspired platforms. We create and train computational models using experimental data, and use these models to predict thrust and power under different fin operating states, providing efficiency profiles. We then use the developed FOM to analyze optimal gaits and compare the performance between different fin materials. These comparisons provide a better understanding of how fin materials affect our thrust generation and propulsive efficiency, allowing us to inform control systems and weight for efficiency on an inverse gait-selector model.