34 citations · 325 across the 33 of their papers we have counts for
34 papers
Data-driven geometric phase in biological locomotion
Pyae Hein Htet, Kenta Ishimoto
Geometric phase quantifies net locomotion in dissipative media via gauge theory, but linking this theoretical quantity to noisy, sparse, and weakly periodic biological shape data i…
Geometric formulation of state-dependent Langevin dynamics using scalar free energy
Kento Yasuda, Zhongqiang Xiong, Zhanglin Hou +3
Stochastic dynamics with state-dependent diffusion arise broadly in confined, anisotropic, and hydrodynamically coupled systems. The conventional Langevin equation contains a spuri…
Covariant Onsager and Onsager-Machlup principles for active and inertial dynamics
Kento Yasuda, Bin Zheng, Zhongqiang Xiong +5
The Onsager principle provides a variational route to the phenomenological equations of dissipative dynamics through the minimization of the Rayleighian. We develop a covariant for…
Neural optimization of the most probable paths of 3D active Brownian particles
Bin Zheng, Zhongqiang Xiong, Changhao Li +7
We develop a variational neural-network framework to determine the most probable path (MPP) of a 3D active Brownian particle (ABP) by directly minimizing the Onsager-Machlup integr…
Demon's variational principle for informational active matter
Kento Yasuda, Kenta Ishimoto, Shigeyuki Komura
The interplay between information, dissipation, and control is reshaping our understanding of thermodynamics in feedback-regulated systems. We develop the informational Onsager-Mac…
Bending-compression coupling in extensible slender microswimmers
Kenta Ishimoto, Johann Herault, Clément Moreau
Undulatory slender objects have been a central theme in the hydrodynamics of swimming at low Reynolds number, where the slender body is usually assumed to be inextensible, although…
Motility and rotation of multi-timescale microswimmers in linear background flows
Eamonn A. Gaffney, Kenta Ishimoto, Benjamin J. Walker
Microswimming cells and robots exhibit diverse behaviours due to both their swimming and their environment. One of the core environmental features impacting inertialess swimming is…
Robust undulatory locomotion via neuromechanical adjustments in a dissipative medium
Kenta Ishimoto, Clément Moreau, Johann Herault
Dissipative environments are ubiquitous in nature, from microscopic swimmers in low-Reynolds-number fluids to macroscopic animals in frictional media. In this study, motivated by v…
Statistical formulation of Onsager-Machlup variational principle
Kento Yasuda, Kenta Ishimoto, Shigeyuki Komura
Onsager's variational principle (OVP) provides us with a systematic way to derive dynamical equations for various soft matter and active matter. By reformulating the Onsager-Machlu…
Emergence of odd elasticity in a microswimmer using deep reinforcement learning
Li-Shing Lin, Kento Yasuda, Kenta Ishimoto +1
We use the Deep Q-Network with reinforcement learning to investigate the emergence of odd elasticity in an elastic microswimmer model. For an elastic microswimmer, it is challengin…
Reciprocal microswimming in fluctuating and confined environments
Yoshiki Hiruta, Kenta Ishimoto
From bacteria and sperm cells to artificial microrobots, self-propelled microscopic objects at low Reynolds numbers often perceive fluctuating mechanical and chemical stimuli and c…
Odd elastohydrodynamics: non-reciprocal living material in a viscous fluid
Kenta Ishimoto, Clément Moreau, Kento Yasuda
Motility is a fundamental feature of living matter, encompassing single cells and collective behavior. Such living systems are characterized by non-conservativity of energy and a l…
Jeffery's orbits and microswimmers in flows: A theoretical review
Kenta Ishimoto
In this review, we provide a theoretical introduction to Jeffery's equations for the orientation dynamics of an axisymmetric object in a flow at low Reynolds number, and review rec…
Generalised Jeffery's equations for rapidly spinning particles. Part 1: Spheroids
Mohit P. Dalwadi, Clément Moreau, Eamonn A. Gaffney +2
The observed behaviour of passive objects in simple flows can be surprisingly intricate, and is complicated further by object activity. Inspired by the motility of bacterial swimme…
Generalised Jeffery's equations for rapidly spinning particles. Part 2: Helicoidal objects with chirality
Mohit P. Dalwadi, Clément Moreau, Eamonn A. Gaffney +2
In this two-part study, we investigate the motion of rigid, active objects in shear Stokes flow, focusing on bodies that induce rapid rotation as part of their activity. In Part 2,…
Odd elasticity of a catalytic micromachine
Akira Kobayashi, Kento Yasuda, Kenta Ishimoto +4
We perform numerical simulations of a model micromachine driven by catalytic chemical reactions. Our model includes a mechano-chemical coupling between the structural variables and…
Onsager's variational principle for nonreciprocal systems with odd elasticity
Li-Shing Lin, Kento Yasuda, Kenta Ishimoto +2
Using Onsager's variational principle, we derive dynamical equations for a nonequilibrium active system with odd elasticity. The elimination of the extra variable that is coupled t…
Shapes optimising grand resistance tensor entries for a rigid body in a Stokes flow
Clment Moreau, Kenta Ishimoto, Yannick Privat
We investigate the optimal shapes of the hydrodynamic resistance of a rigid body set in motion in a Stokes flow. In this low Reynolds number regime, the hydrodynamic drag propertie…
Most probable path of an active Brownian particle
Kento Yasuda, Kenta Ishimoto
In this study, we investigate the transition path of a free active Brownian particle (ABP) on a two-dimensional plane between two given states. The extremum conditions for the most…
A hydrodynamic slender-body theory for local rotation at zero Reynolds number
Benjamin J. Walker, Kenta Ishimoto, Eamonn A. Gaffney
Slender objects are commonplace in microscale flow problems, from soft deformable sensors to biological filaments such as flagella and cilia. Whilst much research has focussed on t…
Emergent rheotaxis of shape-changing swimmers in Poiseuille flow
Benjamin J. Walker, Kenta Ishimoto, Clément Moreau +2
A simple model for the motion of shape-changing swimmers in Poiseuille flow was recently proposed and numerically explored by Omori et al. (2022). These explorations hinted that a…
Time-correlation functions for odd Langevin systems
Kento Yasuda, Kenta Ishimoto, Akira Kobayashi +4
We investigate the statistical properties of fluctuations in active systems that are governed by non-symmetric responses. Both an underdamped Langevin system with an odd resistance…
The effects of rapid yawing on simple swimmer models and planar Jeffery's orbits
Benjamin J. Walker, Kenta Ishimoto, Eamonn A. Gaffney +2
Over a sufficiently long period of time, or from an appropriate distance, the motion of many swimmers can appear smooth, with their trajectories appearing almost ballistic in natur…
Squirmer hydrodynamics near a periodic surface topography
Kenta Ishimoto, Eamonn A. Gaffney, David J. Smith
The behaviour of microscopic swimmers has previously been explored near large scale confining geometries and in the presence of very small-scale surface roughness. Here we consider…