Publications associées à Hidden attractor

Stability: a search for structure

In this thesis we study stability from several viewpoints. After covering the practical importance, the rich history and the ever-growing list of manifestations of stability, we study the following. (i) (Statistical identification of stable dynamical syste ...

EPFL2024

The dynamics of unsteady frictional slip pulses

Thibault Didier Roch, Fabian Barras

Self-healing slip pulses are major spatiotemporal failure modes of frictional systems, featuring a characteristic size L(t) and a propagation velocity c(p)(t) (t is time). Here, we develop a theory of slip pulses in realistic rate- and state-dependent fric ...

National Academy of Sciences2023

Invariant tori in dissipative hyperchaos

Tobias Schneider, Jeremy Peter Parker

One approach to understand the chaotic dynamics of nonlinear dissipative systems is the study of non-chaotic yet dynamically unstable invariant solutions embedded in the system's chaotic attractor. The significance of zero-dimensional unstable fixed points ...

American Institute of Physics2022

Linearization and Identification of Multiple-Attractor Dynamical Systems through Laplacian Eigenmaps

Aude Billard, Bernardo Fichera

Dynamical Systems (DS) are fundamental to the modeling and understanding time evolving phenomena, and have application in physics, biology and control. As determining an analytical description of the dynamics is often difficult, data-driven approaches are ...

Microtome Publishing2022

Automatic locking of a parametrically resonating, base-excited, nonlinear beam

Amit Yedidia Dolev

Described is a closed-loop control scheme capable of stabilizing a parametrically excited nonlinear structure in several vibration modes. By setting the relative phase between the spatially filtered response and the excitation, the open-loop unstable solut ...

SPRINGER2021

Invariant states in inclined layer convection. Part 1. Temporal transitions along dynamical connections between invariant states

Tobias Schneider, Florian Reetz

Thermal convection in an inclined layer between two parallel walls kept at different fixed temperatures is studied for fixed Prandtl number . Depending on the angle of inclination and the imposed temperature difference, the flow exhibits a large variety of ...

Cambridge University Press2020

Invariant states in inclined layer convection. Part 2. Bifurcations and connections between branches of invariant states

Tobias Schneider, Florian Reetz

Convection in a layer inclined against gravity is a thermally driven non-equilibrium system, in which both buoyancy and shear forces drive spatio-temporally complex flows. As a function of the strength of thermal driving and the angle of inclination, a mul ...

Cambridge University Press2020

A critically degenerate elliptic Dirichlet problem, spectral theory and bifurcation

Charles Stuart

In an open, bounded subset Omega of R-N such that 0 is an element of Omega we consider the nonlinear eigenvalue problem -Sigma(N)(i,j,=1) partial derivative(i){A(ij)(x)partial derivative(j)u} + V(x)u + n(x,del u)+ g(x, u) = lambda u in Omega integral(Omega ...

2020

The epsilon expansion meets semiclassics

Riccardo Rattazzi, Alexander Monin, Gil Badel, Gabriel Francisco Cuomo

We study the scaling dimension Delta(phi n) of the operator phi(n) where phi is the fundamental complex field of the U(1) model at the Wilson-Fisher fixed point in d = 4 - epsilon. Even for a perturbatively small fixed point coupling lambda*, standard pert ...

Springer Nature2019

Form finding in elastic gridshells

Pedro Miguel Nunes Pereira de Almeida Reis, Changyeob Baek

Elastic gridshells comprise an initially planar network of elastic rods that are actuated into a shell-like structure by loading their extremities. The resulting actuated form derives from the elastic buckling of the rods subjected to inextensibility. We s ...

National Academy of Sciences2018

Bidirectional motion of filaments: the role of motor proteins and passive cross linkers

Ignacio Pagonabarraga Mora

In eukaryotic cells, motor proteins (MPs) bind to cytoskeletal filaments and move along them in a directed manner generating active stresses. During cell division a spindle structure of overlapping antiparallel microtubules forms whose stability and dynami ...

Royal Soc Chemistry2017

Bifurcation points of a singular boundary-value problem on (0,1)

Charles Stuart

Following earlier work on some special cases [17,11] and on the analogous problem in higher dimensions [10,20], we make a more thorough investigation of the bifurcation points for a nonlinear boundary value problem of the form -{A(x)u' (x)}'.= f (lambda, x ...

Academic Press Inc Elsevier Science2016

Control and Learning of Compliant Manipulation Skills

Klas Jonas Alfred Kronander

Humans demonstrate an impressive capability to manipulate fragile objects without damaging them, graciously controlling the force and position of hands or tools. Traditionally, robotics has favored position control over force control to produce fast, accur ...

EPFL2015

Codimension one stability of the catenoid under the vanishing mean curvature flow in Minkowski space

Joachim Krieger, Roland Donninger, Willie Wai Yeung Wong

We study time-like hypersurfaces with vanishing mean curvature in the (3+1) dimensional Minkowski space, which are the hyperbolic counterparts to minimal embeddings of Riemannian manifolds. The catenoid is a stationary solution of the associated Cauchy pro ...

Duke Univ Press2015

Secondary instability and tertiary states in rotating plane Couette flow

Tobias Schneider

Recent experimental studies have shown rich transition behaviour in rotating plane Couette flow (RPCF). In this paper we study the transition in supercritical RPCF theoretically by determination of equilibrium and periodic orbit tertiary states via Floquet ...

Cambridge University Press2014

Learning Reach-to-Grasp Motions From Human Demonstrations

Ashwini Shukla

Reaching over to grasp an item is arguably the most commonly used motor skill by humans. Even under sudden perturbations, humans seem to react rapidly and adapt their motion to guarantee success. Despite the apparent ease and frequency with which we use th ...

EPFL2014

Dynamical Movement Primitives: Learning Attractor Models for Motor Behaviors

Auke Ijspeert

Nonlinear dynamical systems have been used in many disciplines to model complex behaviors, including biological motor control, robotics, perception, economics, traffic prediction, and neuroscience. While often the unexpected emergent behavior of nonlinear ...

Massachusetts Institute of Technology Press2013

Dynamics of Stochastically Blinking Systems. Part II: Asymptotic Properties

Martin Hasler, Igor Belykh

We study stochastically blinking dynamical systems as in the companion paper (Part I). We analyze the asymptotic properties of the blinking system as time goes to infinity. The trajectories of the averaged and blinking system cannot stick together forever, ...

Siam Publications2013

Augmented-SVM: Automatic space partitioning for combining multiple non-linear dynamics

Ashwini Shukla

Non-linear dynamical systems (DS) have been used extensively for building generative models of human behavior. Their applications range from modeling brain dynamics to encoding motor commands. Many schemes have been proposed for encoding robot motions usin ...

Curran Associates, Inc.2012

Towards simple control for complex, autonomous robotic applications: Combining discrete and rhythmic motor primitives

Auke Ijspeert, Ludovic Righetti, Sarah Dégallier Rochat, Sébastien Gay

Vertebrates are able to quickly adapt to new environments in a very robust, seemingly effortless way. To explain both this adaptivity and robustness, a very promising perspective in neurosciences is the modular approach to movement generation: Movements re ...

Springer Verlag2011