Enhancing the Mobility of Small-Scale Robots Via Nonlinear Structural Springs Exhibiting Negative Stiffness

Journal of Applied Mechanics, Год журнала: 2024, Номер 91(8)

Опубликована: Апрель 17, 2024

Abstract Compared to traditional robotic systems, small-scale robots, ranging from several millimeters micrometres in size, are capable of reaching narrower and vulnerable regions with minimal damage. However, conventional robots’ limited maneuverability controlability hinder their ability effectively navigate the intricate environments, such as gastrointestinal tract. Self-propelled capsule robots driven by vibrations impacts emerge a promising solution, holding potentials enhance diagnostic accuracy, enable targeted drug delivery, alleviate patient discomfort during endoscopic procedures. This paper builds upon our previous work on self-propelled exploring potential nonlinear connecting springs its propulsion capabilities. Leveraging mathematical model for self-propelling von Mises truss spring, which is verified using finite element model, we investigate effects negative stiffness snap-back within structural spring propelling speed. Our analysis reveals that can significantly reduce sensitivity speed excitation frequency. As result, robot exhibits remarkably wider operational band where it maintains high average speed, surpassing linear counterpart. sheds light developing customized systems diverse scenarios applications, opening up new possibilities enhanced functionality various biomedical applications.

Язык: Английский

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Quantifying spectral information about source separation in multisource odour plumes

PLoS ONE, Год журнала: 2025, Номер 20(1), С. e0297754 - e0297754

Опубликована: Янв. 10, 2025

Odours released by objects in natural environments can contain information about their spatial locations. In particular, the correlation of odour concentration timeseries produced two spatially separated sources contains distance between sources. For example, mice are able to distinguish correlated and anti-correlated fluctuations at frequencies up 40 Hz, while insect olfactory receptor neurons resolve exceeding 100 Hz. Can this high-frequency acuity support source localization? Here we answer question quantifying separation contained spectral constituents correlations. We used computational fluid dynamics simulations multisource plumes two-dimensional chaotic flow generate temporally complex, covarying fields. By relating these fields decompositions associated timeseries, making simplifying assumptions statistics decompositions, derived analytic expressions for Fisher components correlations separation. computed a broad range separations three different arrangements found that high were more informative than low when close relative sizes large eddies flow. observed qualitatively similar effect an independent set with geometry, but not surrogate data power spectrum our which all priori equally informative. Our work suggests systems may high-resolution localization also provide model distribution is accurate over separations. More broadly, establishes approach quantification timeseries.

Язык: Английский

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Accelerating the Design of Self-Guided Microrobots in Time-Varying Magnetic Fields

JACS Au, Год журнала: 2023, Номер 3(3), С. 611 - 627

Опубликована: Март 10, 2023

Mobile robots combine sensory information with mechanical actuation to move autonomously through structured environments and perform specific tasks. The miniaturization of such the size living cells is actively pursued for applications in biomedicine, materials science, environmental sustainability. Existing microrobots based on field-driven particles rely knowledge particle position target destination control motion fluid environments. Often, however, these external strategies are challenged by limited global where a common field directs multiple unknown positions. In this Perspective, we discuss how time-varying magnetic fields can be used encode self-guided behaviors conditioned local cues. Programming framed as design problem: seek identify variables (e.g., shape, magnetization, elasticity, stimuli-response) that achieve desired performance given environment. We accelerating process using automated experiments, computational models, statistical inference, machine learning approaches. Based current understanding dynamics existing capabilities fabrication actuation, argue potentially transformative close at hand.

Язык: Английский

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Liquid Crystal Networks Meet Water: It's Complicated!

Advanced Materials, Год журнала: 2023, Номер 36(12)

Опубликована: Июль 1, 2023

Soft robots are composed of compliant materials that facilitate high degrees freedom, shape-change adaptability, and safer interaction with humans. An attractive choice material for soft robotics is crosslinked networks liquid crystal polymers (LCNs), as they responsive to a wide variety external stimuli capable undergoing fast, programmable, complex shape morphing, which allows their use in range robotic applications. However, unlike hydrogels, another popular robotics, LCNs have limited applicability flooded or aquatic environments. This can be attributed not only the poor efficiency common LCN actuation methods underwater but also complicated relationship between water. In this review, water elaborated existing body literature surveyed where LCNs, both hygroscopic non-hygroscopic, utilized Then challenges face widespread adaptation applications discussed and, finally, possible paths forward successful environments envisaged.

Язык: Английский

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Magnetic Hydrogel Micromachines with Active Release of Antibacterial Agent for Biofilm Eradication

Advanced Intelligent Systems, Год журнала: 2023, Номер 6(2)

Опубликована: Май 24, 2023

Bacterial biofilms are widely found in nature, and they can be a major factor many local chronic infections inside the human body. To date, effective elimination of is intractable for conventional antibiotic therapies due to existence bacteria‐protecting extracellular polymeric substances. For biofilm eradication tiny tubular structures, magnetic hydrogel micromachines (MHM) designed that capable performing mechanical disruption while releasing antibacterial agents controllable fashion. Two modes motion controlled by external fields, namely planar rotation wobbling modes, have been investigated drive interact destruct biofilms. In addition, presented composed thermosensitive PNIPAm load with agent (H 2 O ) release them upon heating. The Fe 3 4 nanoparticles embedded matrix act as catalysts Fenton reaction, generating bacteria‐killing free radicals. synergetic effect has experimentally demonstrated well plates small tubes. MHMs may provide new design treat biofilm‐related narrow confined spaces.

Язык: Английский

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