Publications by Jonas Buchli | EPFL Graph Search

Towards practical reinforcement learning for tokamak magnetic control

Jonas Buchli, Federico Alberto Alfredo Felici, Cristian Galperti, Brendan Tracey

Reinforcement learning (RL) has shown promising results for real-time control systems, including the domain of plasma magnetic control. However, there are still significant drawbacks compared to traditional feedback control approaches for magnetic confinem ...

Elsevier Science Sa2024

Magnetic control of tokamak plasmas through deep reinforcement learning

Basil Duval, Ambrogio Fasoli, Jean-Marc Moret, Olivier Sauter, Stefano Coda, Jonas Buchli, Federico Alberto Alfredo Felici, Antoine Pierre Emmanuel Alexis Merle, Cristian Galperti, Francesco Carpanese, Federico Pesamosca, Cristian Sommariva, Jonas Degrave, Brendan Tracey

Nuclear fusion using magnetic confinement, in particular in the tokamak configuration, is a promising path towards sustainable energy. A core challenge is to shape and maintain a high-temperature plasma within the tokamak vessel. This requires high-dimensi ...

2022

Slow-fast Dynamics of Strongly Coupled Adaptive Frequency Oscillators

Auke Ijspeert, Ludovic Righetti, Jonas Buchli

Oscillators have two main limitations: their synchronization properties are limited (i.e., they have a finite synchronization region) and they have no memory of past interactions (i.e., they return to their intrinsic frequency whenever the entraining signa ...

SIAM PUBLICATIONS2021

Learning motions from demonstrations and rewards with time-invariant dynamical systems based policies

Aude Billard, Jonas Buchli, Joël Rey, Klas Jonas Alfred Kronander, Farbod Farshidian

2017

Adaptive Frequency Oscillators and Applications

Auke Ijspeert, Ludovic Righetti, Jonas Buchli

In this contribution we present a generic mechanism to transform an oscillator into an adaptive frequency oscillator, which can then dynamically adapt its parameters to learn the frequency of any periodic driving signal. Adaptation is done in a dynamic way ...

2009

Frequency analysis with coupled nonlinear oscillators

Auke Ijspeert, Ludovic Righetti, Jonas Buchli

We present a method to obtain the frequency spectrum of a signal with a nonlinear dynamical system. The dynamical system is composed of a pool of adaptive frequency oscillators with negative mean-field coupling. For the frequency analysis, the synchronizat ...

2008

Self-organized adaptive legged locomotion in a compliant quadruped robot

Auke Ijspeert, Jonas Buchli

In this contribution we present experiments of an adaptive locomotion controller on a compliant quadruped robot. The adaptive controller consists of adaptive frequency oscillators in different configurations and produces dynamic gaits such as bounding and ...

2008

Engineering limit cycle systems : adaptive frequency oscillators and applications to adaptive locomotion control of compliant robots

Jonas Buchli

In this thesis, we present a dynamical systems approach to adaptive controllers for locomotion control. The approach is based on a rigorous mathematical framework using nonlinear dynamical systems and is inspired by theories of self-organization. Nonlinear ...

EPFL2007

Resonant neurons and bushcricket behaviour

Auke Ijspeert, Jonas Buchli

The resonant properties of the intrinsic dynamics of single neurons could play a direct role in behaviour. One plausible role is in the recognition of temporal patterns, such as that seen in the auditory communication systems of Orthoptera. Recent behaviou ...

2007

Dynamical principles in neuronal systems and robotics

Auke Ijspeert, Jonas Buchli

2006

Engineering Entrainment and Adaptation in Limit Cycle Systems -- From biological inspiration to applications in robotics

Auke Ijspeert, Ludovic Righetti, Jonas Buchli

2006

Finding Resonance: Adaptive Frequency Oscillators for Dynamic Legged Locomotion

Auke Ijspeert, Jonas Buchli

IEEE2006

Adaptive Four Legged Locomotion Control Based on Nonlinear Dynamical Systems

Auke Ijspeert, Jonas Buchli

Springer Verlag2006

Adaptive Frequency Oscillators applied to dynamic walking II. Adapting to resonant body dynamics

Auke Ijspeert, Ludovic Righetti, Jonas Buchli

2006

Adaptive dynamical systems: A promising tool for embodied artificial intelligence

Auke Ijspeert, Ludovic Righetti, Jonas Buchli

2006

Dynamic hebbian learning in adaptive frequency oscillators

Auke Ijspeert, Ludovic Righetti, Jonas Buchli

Nonlinear oscillators are widely used in biology, physics and engineering for modeling and control. They are interesting because of their synchronization properties when coupled to other dynamical systems. In this paper, we propose a learning rule for osci ...

2006

Programmable Central Pattern Generators

Auke Ijspeert, Ludovic Righetti, Jonas Buchli

EPFL2006

Nonlinear modelling of double and triple period pitch breaks in vocal fold vibration

Auke Ijspeert, Fritz Menzer, Jonas Buchli

This paper reports a study on short-time subharmonic pitch breaks in vocal fold vibration, which are found to be a common feature of the human voice in spoken language. The observed pitch breaks correspond to a change in periodicity of the electrolaryngogr ...

2006

Institute Presentation: Biologically Inspired Robotics Group at EPFL

Auke Ijspeert, Alessandro Crespi, Ludovic Righetti, Jonas Buchli

2005