English
Related papers

Related papers: Tuning upstream swimming of micro-robots by shape …

200 papers

Swimming consists by definition in propelling through a fluid by means of bodily movements. Thus, from a mathematical point of view, swimming turns into a control problem for which the controls are the deformations of the swimmer. The aim…

Optimization and Control · Mathematics 2017-02-15 Thomas Chambrion , Laetitia Giraldi , Alexandre Munnier

We train active neural-network flow controllers using a deep learning PDE augmentation method to optimize lift-to-drag ratios in turbulent airfoil flows at Reynolds number $5\times10^4$ and Mach number 0.4. Direct numerical simulation and…

Fluid Dynamics · Physics 2025-10-09 Xuemin Liu , Tom Hickling , Jonathan F. MacArt

In a fluid environment, flagellated microswimmers propel themselves by rotating their flagella. The morphology of these flagella significantly influences forward speed, swimming efficiency, and directional stability, which are critical for…

Fluid Dynamics · Physics 2025-06-25 Baopi Liu , Lu Chen , Wenjun Xu

Deformable robots are notoriously difficult to model or control due to its high-dimensional configuration spaces. Direct trajectory optimization suffers from the curse-of-dimensionality and incurs a high computational cost, while…

Robotics · Computer Science 2023-11-06 Chen Liang , Xifeng Gao , Kui Wu , Zherong Pan

For robots to handle the numerous factors that can affect them in the real world, they must adapt to changes and unexpected events. Evolutionary robotics tries to solve some of these issues by automatically optimizing a robot for a specific…

Robotics · Computer Science 2018-05-10 Tønnes F. Nygaard , Charles P. Martin , Eivind Samuelsen , Jim Torresen , Kyrre Glette

Swimming organisms can escape their predators by creating and harnessing unsteady flow fields through their body motions. Stochastic optimization and flow simulations have identified escape patterns that are consistent with those observed…

Fluid Dynamics · Physics 2021-09-29 Ioannis Mandralis , Pascal Weber , Guido Novati , Petros Koumoutsakos

Magnetic microrobots that swim through liquid media are of interest for minimally invasive medical procedures, bioengineering, and manufacturing. Many of the envisaged applications, such as micromanipulation and targeted cargo delivery,…

Soft Condensed Matter · Physics 2020-04-03 Joshua Giltinan , Panayiota Katsamba , Wendong Wang , Eric Lauga , Metin Sitti

This paper presents a robot control algorithm suitable for safe reactive navigation tasks in cluttered environments. The proposed approach consists of transforming the robot workspace into the \emph{ball world}, an artificial representation…

Robotics · Computer Science 2024-11-25 Gennaro Notomista , Gary P. T. Choi , Matteo Saveriano

High-precision micromanipulation techniques, including optical tweezers and hydrodynamic trapping, have garnered wide-spread interest. Recent advances in optofluidic multiplexed assembly and microrobotics demonstrate significant progress,…

Fluid Dynamics · Physics 2025-11-03 Elena Erben , Ivan Saraev , Weida Liao , Fan Nan , Eric Lauga , Moritz Kreysing

Microswimmers (planktonic microorganisms or artificial active particles) immersed in a fluid interact with the ambient flow, altering their trajectories. In surface gravity waves, a common goal for microswimmers is vertical migration (e.g.,…

Soft Condensed Matter · Physics 2022-03-01 Kunlin Ma , Nimish Pujara , Jean-Luc Thiffeault

Here we show that micro-swimmers can form a concealed swarm through synergistic cooperation in suppressing one another's disturbing flows. We then demonstrate how such a concealed swarm can actively gather around a favorite spot, point…

Fluid Dynamics · Physics 2020-07-24 Mehdi Mirzakhanloo , Mohammad-Reza Alam

Living microorganisms are capable of a tactic response to external stimuli by swimming towards or away from the stimulus source; they do so by adapting their tactic signal transduction pathways to the environment. Their self-motility thus…

Soft Condensed Matter · Physics 2016-10-12 Alexander Geiseler , Peter Hänggi , Fabio Marchesoni , Colm Mulhern , Sergey Savel'ev

Many aquatic organisms are able to track ambient flow disturbances and locate their source. These tasks are particularly challenging because they require the organism to sense local flow information and respond accordingly. Details of how…

Optimization and Control · Mathematics 2018-04-10 Brendan Colvert , Eva Kanso

An artificial microswimmer drifts in response to spatio-temporal modulations of an activating suspension medium. We consider two competing mechanisms capable of influencing its tactic response: angular fluctuations, which help it explore…

Soft Condensed Matter · Physics 2017-02-15 Alexander Geiseler , Peter Hänggi , Fabio Marchesoni

In Nature, liquids often circulate in channels textured with leaflets, cilia or porous walls that deform with the flow. These soft structures are optimized to passively control flows and inspire the design of novel microfluidic and soft…

Soft Condensed Matter · Physics 2020-08-19 Martin Brandenbourger , Adrien Dangremont , Rudolf Sprik , Corentin Coulais

We present an optimization-based motion planning algorithm to compute a smooth, collision-free trajectory for a manipulator used to transfer a liquid from a source to a target container. We take into account fluid dynamics constraints as…

Robotics · Computer Science 2016-03-09 Zherong Pan , Dinesh Manocha

Inside cells, various cargos are transported by teams of molecular motors. Intriguingly, the motors involved generally have opposite pulling directions, and the resulting cargo dynamics is a biased stochastic motion. It is an open question…

Biological Physics · Physics 2017-09-20 Sarah Klein , Cécile Appert-Rolland , Ludger Santen

Microorganisms living in microfluidic environments often form multi-species swarms, where they can leverage collective motions to achieve enhanced transport and spreading. Nevertheless, there is a general lack of physical understandings of…

Fluid Dynamics · Physics 2022-02-14 Bryce Palmer , Wen Yan , Tong Gao

The flow downstream a backward-facing step is controlled using a pulsed jet placed upstream of the step edge. Experimental velocity fields are computed and used to the recirculation area quantify. The effects of jet amplitude, frequency and…

Fluid Dynamics · Physics 2015-06-19 Nicolas Gautier , Jean-Luc Aider

Robots built from soft materials can alter their shape and size in a particular profile. This shape-changing ability could be extremely helpful for rescue robots and those operating in unknown terrains and environments. In changing shape,…

Robotics · Computer Science 2016-05-13 Vishesh Vikas , Eliad Cohen , Rob Grassi , Canberk Sozer , Barry Trimmer