Leveraging three-dimensionality for navigation in bluff-body wakes

Biological flyers and swimmers navigate in unsteady wake flows using limited sensory abilities and actuation energies. Understanding how vortical structures can be leveraged for energy-efficient navigation in unsteady flows is beneficial in developing autonomous navigation for small-scale aerial and...

Full description

Saved in:
Bibliographic Details
Main Authors: Vedasri Godavarthi, Kartik Krishna, Steven L. Brunton, Kunihiko Taira
Format: Article
Language:English
Published: Cambridge University Press 2025-01-01
Series:Flow
Subjects:
Online Access:https://www.cambridge.org/core/product/identifier/S2633425925000030/type/journal_article
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Biological flyers and swimmers navigate in unsteady wake flows using limited sensory abilities and actuation energies. Understanding how vortical structures can be leveraged for energy-efficient navigation in unsteady flows is beneficial in developing autonomous navigation for small-scale aerial and marine vehicles. Such vehicles are typically operated with constrained onboard actuation and sensing capabilities, making energy-efficient trajectory planning critically important. This study finds that trajectory planners can leverage three-dimensionality appearing in a complex unsteady wake for efficient navigation using limited flowfield information. This is revealed with comprehensive investigations by finite-horizon model-predictive control for trajectory planning of a swimmer behind a cylinder wake at Reynolds number of 300. The navigation performance of three-dimensional cases is compared with scenarios in a two-dimensional (2-D) wake. The underactuated swimmer is able to reach the target by leveraging the background flow when the prediction horizon exceeds one-tenth of the wake-shedding period, demonstrating that navigation is feasible with limited information about the flowfield. Further, we identify that the swimmer can leverage the secondary transverse vortical structures to reach the target faster than is achievable navigating in a 2-D wake.
ISSN:2633-4259