Maneuvering of an underwater vehicle using bio-inspired pectoral fins

TL;DR

This paper presents a bio-inspired control system for an underwater vehicle equipped with pectoral fins, demonstrating effective maneuvering and force generation based on fin kinematics.

Contribution

It introduces a novel bio-inspired fin design and characterizes the forces generated, enabling improved maneuverability of underwater vehicles.

Findings

Streamwise forces depend mainly on fin's projected frontal area.

Lateral forces are influenced by Strouhal number.

Symmetric and anti-symmetric fin motions control lateral and streamwise forces.

Abstract

A Cyber-physical underwater vehicle is equipped with bio-inspired flapping fins positioned on the sides of the vehicle's main body. The proposed control surfaces are inspired by fish pectoral fins, generating forces and moments that can potentially be harnessed for maneuvering, hovering and station keeping. The streamwise and cross-stream forces produced by the fins are characterized for a range of reduced frequencies and Strouhal numbers. The streamwise forces are shown to be predominantly a function of the fin's projected frontal area, while the lateral forces also depend on the Strouhal number. When operated simultaneously, different flapping synchronizations can be employed for specific goals; a symmetric motion suppresses the lateral forces, while an anti-symmetric motion decreases the peaks of the streamwise force produced. The Cyber-physical vehicle demonstrates how the pair of fins can successfully maneuver the vehicle in the lateral direction.