Pleobot: a modular robotic solution for metachronal swimming

TL;DR

Pleobot is a modular, krill-inspired robotic platform designed to study metachronal swimming, combining bio-inspired design with active and passive joint actuation to explore propulsion mechanisms and fluid dynamics.

Contribution

This work introduces the first comprehensive robotic platform for studying metachronal propulsion, integrating bio-inspired design, active/passive actuation, and modularity for hypothesis testing.

Findings

Flow produced by Pleobot correlates with thrust.

Identification of a leading-edge suction effect contributing to lift.

Modularity allows independent testing of motion traits.

Abstract

Metachronal locomotion is a widespread swimming mode used by aquatic swarming organisms to achieve performance and maneuverability in the intermediate Reynolds number regime. Our understanding of the mechanisms driving these abilities is limited due to the challenges of studying live organisms. Designs inspired by nature present an approach for developing small and maneuverable underwater self-propelled robots. Here, we present the design, manufacture, and validation of the \emph{Pleobot} --a unique krill-inspired robotic swimming appendage constituting the first platform to study metachronal propulsion comprehensively. Our methods combine a multi-link 3D printed mechanism with active and passive actuation of the joints to generate natural kinematics. Using force and fluid flow measurements in parallel with biological data, we show the link between the flow produced by the appendage and thrust. Further, we provide the first account of a leading-edge suction effect that contributes to lift during the power stroke. The repeatability and modularity of the \emph{Pleobot} enable the independent manipulation of particular motions and traits to test hypotheses central to understanding the relationship between form and function. Lastly, we outline future directions for the \emph{Pleobot}, including adapting morphological features. We foresee a broad appeal to a wide array of scientific disciplines, from fundamental studies in ecology, biology, and engineering, to developing new platforms for studying oceans across the solar system.