1
|
Justus N, Hatton R. Optimal gaits for inertia-dominated swimmers with passive elastic joints. Phys Rev E 2024; 109:034602. [PMID: 38632746 DOI: 10.1103/physreve.109.034602] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2023] [Accepted: 01/23/2024] [Indexed: 04/19/2024]
Abstract
Animals and some robots locomote by interacting with the environment through cyclic shape changes, or gaits. Many animals make significant use of passive dynamics with flexible tails or pendulum action to reduce the effort required to execute these gaits. Although geometric tools have been developed to study optimal passive gaits for swimmers in drag-dominated physics regimes, they have not yet been used to study larger-scale swimmers whose physics are dominated by inertial effects. In this paper, we leverage previous work in the geometric mechanics field to examine passive-elastic inertial swimmers and show that geometric mechanics can be used to rapidly determine many classes of optimal gaits for such systems. We also discuss how considering swimmer metabolic costs in addition to the mechanical costs of driving actuation is useful for discussing swimmer efficiency. In particular, we focus on two models of active-passive swimming inertial systems: the perfect-fluid three-link swimmer, and a swimmer with a passively flexible tail.
Collapse
Affiliation(s)
- Nathan Justus
- Collaborative Institute for Robotics and Intelligent Systems (CoRIS), Oregon State University, Corvallis, Oregon 97331, USA
| | - Ross Hatton
- Collaborative Institute for Robotics and Intelligent Systems (CoRIS), Oregon State University, Corvallis, Oregon 97331, USA
| |
Collapse
|
2
|
Sánchez-Rodríguez J, Raufaste C, Argentina M. Scaling the tail beat frequency and swimming speed in underwater undulatory swimming. Nat Commun 2023; 14:5569. [PMID: 37689714 PMCID: PMC10492801 DOI: 10.1038/s41467-023-41368-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2023] [Accepted: 09/01/2023] [Indexed: 09/11/2023] Open
Abstract
Undulatory swimming is the predominant form of locomotion in aquatic vertebrates. A myriad of animals of different species and sizes oscillate their bodies to propel themselves in aquatic environments with swimming speed scaling as the product of the animal length by the oscillation frequency. Although frequency tuning is the primary means by which a swimmer selects its speed, there is no consensus on the mechanisms involved. In this article, we propose scaling laws for undulatory swimmers that relate oscillation frequency to length by taking into account both the biological characteristics of the muscles and the interaction of the moving swimmer with its environment. Results are supported by an extensive literature review including approximately 1200 individuals of different species, sizes and swimming environments. We highlight a crossover in size around 0.5-1 m. Below this value, the frequency can be tuned between 2-20 Hz due to biological constraints and the interplay between slow and fast muscles. Above this value, the fluid-swimmer interaction must be taken into account and the frequency is inversely proportional to the length of the animal. This approach predicts a maximum swimming speed around 5-10 m.s-1 for large swimmers, consistent with the threshold to prevent bubble cavitation.
Collapse
Affiliation(s)
- Jesús Sánchez-Rodríguez
- Université Côte d'Azur, CNRS, INPHYNI, 17 Rue Julien Lauprêtre, Nice, 06200, France
- Departamento de Física Fundamental, Universidad Nacional de Educación a Distancia, Madrid, 28040, Spain
- Laboratory of Fluid Mechanics and Instabilities, École Polytechnique Fédérale de Lausanne, Lausanne, CH-1015, Switzerland
| | - Christophe Raufaste
- Université Côte d'Azur, CNRS, INPHYNI, 17 Rue Julien Lauprêtre, Nice, 06200, France
- Institut Universitaire de France (IUF), 1 Rue Descartes, Paris, 75005, France
| | - Médéric Argentina
- Université Côte d'Azur, CNRS, INPHYNI, 17 Rue Julien Lauprêtre, Nice, 06200, France.
| |
Collapse
|
3
|
Schwab F, Lunsford ET, Hong T, Wiesemüller F, Kovac M, Park YL, Akanyeti O, Liao JC, Jusufi A. Body Caudal Undulation measured by Soft Sensors and emulated by Soft Artificial Muscles. Integr Comp Biol 2021; 61:1955-1965. [PMID: 34415009 PMCID: PMC8699111 DOI: 10.1093/icb/icab182] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2021] [Revised: 08/15/2021] [Accepted: 08/18/2021] [Indexed: 11/16/2022] Open
Abstract
We propose the use of bio-inspired robotics equipped with soft sensor technologies to gain a better understanding of the mechanics and control of animal movement. Soft robotic systems can be used to generate new hypotheses and uncover fundamental principles underlying animal locomotion and sensory capabilities, which could subsequently be validated using living organisms. Physical models increasingly include lateral body movements, notably back and tail bending, which are necessary for horizontal plane undulation in model systems ranging from fish to amphibians and reptiles. We present a comparative study of the use of physical modeling in conjunction with soft robotics and integrated soft and hyperelastic sensors to monitor local pressures, enabling local feedback control, and discuss issues related to understanding the mechanics and control of undulatory locomotion. A parallel approach combining live animal data with biorobotic physical modeling promises to be beneficial for gaining a better understanding of systems in motion.
Collapse
Affiliation(s)
- Fabian Schwab
- Locomotion in Biorobotic and Somatic Systems Group, Max Planck Institute for Intelligent Systems, Heisenbergstraße 3, 70569, Stuttgart, Germany
| | - Elias T Lunsford
- Department of Biology, Whitney Laboratory for Marine Bioscience, University of Florida, Saint Augustine, Florida, 32080, U.S.A
| | - Taehwa Hong
- Department of Mechanical Engineering, Seoul National University, Seoul, 08826, Korea
| | - Fabian Wiesemüller
- Materials and Technology Center of Robotics, EMPA, Überlandstrasse 129, Zürich, 8600, Switzerland.,Aerial Robotics Lab (ARL), Department of Aeronautics, Imperial College London, South Kensington Campus, London, SW7 2AZ, UK
| | - Mirko Kovac
- Materials and Technology Center of Robotics, EMPA, Überlandstrasse 129, Zürich, 8600, Switzerland.,Aerial Robotics Lab (ARL), Department of Aeronautics, Imperial College London, South Kensington Campus, London, SW7 2AZ, UK
| | - Yong-Lae Park
- Department of Mechanical Engineering, Seoul National University, Seoul, 08826, Korea
| | - Otar Akanyeti
- Department of Biology, Whitney Laboratory for Marine Bioscience, University of Florida, Saint Augustine, Florida, 32080, U.S.A.,Department of Computer Science, Aberystwyth University, Aberystwyth, Ceredigion, SY23 3FL, UK
| | - James C Liao
- Department of Biology, Whitney Laboratory for Marine Bioscience, University of Florida, Saint Augustine, Florida, 32080, U.S.A
| | - Ardian Jusufi
- Locomotion in Biorobotic and Somatic Systems Group, Max Planck Institute for Intelligent Systems, Heisenbergstraße 3, 70569, Stuttgart, Germany
| |
Collapse
|