Abstracts Overview

A new method has been developed to gradually reconstruct the topography of surfaces. The technique involves measuring the changes in the dynamic vibration of a Nanofiber, which is moved parallel to the measured surface and gradually inserted deeper without physical contact. The Nanofiber vibrates an...

We propose a new computational model for migraine-related cortical spreading depression (CSD) by using a neural field framework. The model is extended from the Wilson-Cowan-Amari formalism [1, 2]. It is based on an excitatory-inhibitory neuronal population pair which is coupled to a potassium concen...

Gauss's Principle of Least Constraint allows to interpret the equations of motion of a constrained mechanical system as the ones arising from the minimization of a well defined deviation function which, mathematically, is a least-squares problem. Following previous approaches in which a recursive le...

The loosening of bolts negatively impacts many industries worldwide. This issue, for example, can be responsible for the collapse of a structure or vehicle, leading to environmental disasters, economic loss, injuries, and death. Current strategies for simulating loosening include high-fidelity finit...

Several chemical engineering applications involve global optimization of process models in which nonlinear dynamics are encoded as ordinary differential equations (ODEs). In typical deterministic methods for global optimization, crucial lower bounds are generated by minimizing convex relaxations. He...

In this talk we provide an archetypal double-winged novel nonlinear oscillator composed of torsional springs and rigid rods which behaves smooth and discontinuous dynamics and a kind of special collision pendulum depending on the varying of a geometrical parameter. The system behaves complicated equ...

A new design of power amplifier’s (PA) digital pre-distortion (DPD) model with recursive system identification algorithm based on H-infinite robust control is proposed in this study to improve the accuracy of the model without increasing the computational cost too much. With the development of har...

Self-balancing robots have gained prominence in domestic and industrial applications due to their notably smaller footprint than their naturally stable counterparts. However, the dynamics and control of such robots pose significant engineering challenges. In this study, we develop a planar dynamics ...

A nonlinear energy sink (NES) is a mechanical vibration absorber with mass and nonlinear stiffness, typically a cubic hardening spring. This nonlinear stiffness increases the operational bandwidth of the NES compared to linear vibration absorbers. This work presents and experimentally implements the...

The upper bound response of Nonlinear Parametrically Excited (NPE) systems is investigated. Different systems including a NPE system under pure parametric excitation, a NPE system under interacting external excitation and a NPE cantilever beam with a tip mass are considered. In order to obtain the r...

Uncovering the equations of motion and parameter values for vibrating structures is a significant focus in science, engineering, and technology. This study introduces a novel data-driven approach centered on the system's mechanical energy to identify governing dynamics by examining the forces influe...

Particle filters provide a general and flexible approach to numerically approximate the nonlinear filtering solution, a conditional probability distribution, of continuous-time partially observable stochastic signal processes. In this paper we consider the case of a continuous-time signal and discre...

Differently from linear dynamical systems, the analysis of global dynamics is crucial for ensuring the safety of nonlinear systems due to potential phenomena of multi-stability. Trajectories of transient motions in the phase space contain significant information about global dynamics. However, extra...

We develop a new explicit integration method for transient dynamics computation of viscoelastic materials, surpassing the stability limits of Belytschko’s widely used half-lagged velocity approximation. Based on the central difference (CD) scheme, our method integrates the viscous stress strain la...

The study of the nonlinear behavior of a pre-shaped Micro-ElectroMechanical (MEMS) resonator is numerically investigated. The studied microresonator consists of a clamped-clamped (cc-) beam modeled as an Euler-Bernoulli beam accounting for mid-plane stretching in the in- and out-of-plane vibrations ...

Biomolecular condensates formed by liquid-liquid phase separation allow cells to overcome various challenges in a relatively straightforward manner. Here we propose that cells use specialized condensates to reconstruct epigenetic information that is lost during replication. Chromatin itself plays an...

Mixed-mode oscillations (MMOs) are characterised by a pattern of small-amplitude oscillations (SAOs) and large-amplitude oscillations (LAOs). They typically occur in systems with multiple time scales, for which intersections between slow manifolds are known to organise the number of SAOs. We investi...

We extend the current theory for spectral submanifolds (SSMs) to ones covering slowly varying dynamical systems. Restricting the dynamics onto these SSMs provides one with a mathematically rigorous model reduction technique. We also observe a justified approximation of adiabtic SSMs can be obtained ...

This research extends the Enriched Multiple Scales method to nonlinear partial differential equations (PDEs), illustrating the procedure using a beam with mid-plane stretching. Enriched multiple scales was originally formulated for predicting the periodic response and stability of weakly and, in som...

The phase shift of an oscillator in response to an external stimulus has been used to characterise, understand and predict biological behaviours. Such phase shifts are studied mathematically by first modelling the oscillator as an attracting periodic orbit, and then considering its isochrons. Each i...

This note focuses on the analysis of emergent behaviors in networks of dynamical systems, where their interations are of activation-type locally and inhibitory-type in the long-range. Such interplay between activation and inhibition is reminiscent of the classical formula for oscillations in lumped ...

A new multi degree of freedom (mDOF) metastructure concept that utilizes a hybrid position feedback (HPF) controller is introduced and its characteristics are demonstrated. The concept is based on bistable elements and associated controllers that are unstable-then-stable position feedback controller...

This study introduces a probabilistic approach to assess the stability of aeroelastic limit cycle oscillations. Utilising the Hill/Koopman method, data-driven models are trained to capture eigenvalue behaviour. The stability likelihood of the limit cycle oscillations is evaluated by analysing the pe...

Nonlinear mechanisms leverage nonlinear kinematics to enhance the efficacy of isolators, maintaining controlled static deflections while keeping natural frequencies low. Despite extensive examination of their performance under harmonic base excitation, there is a scarcity of applications incorporati...

This paper presents a novel formulation for multibody systems with unilateral interactions. We address the forward dynamics simulation problem in which the dynamics formulation is solved under given loads, and as a result, the motion is determined. This simulation problem involves two main parts: th...

This contribution provides an overview of recent work carried out within the Data, Vibration and Uncertainty Group (https://sites.google.com/view/dvugroup) focusing on developing Physics-Enhanced Machine Learning strategies in applied mechanics. In particular, it will focus on the problem of the ide...

This talk aims to introduce a statistical approach to identify the stochastic dynamic system behind a measured time series data. The method is formulated as a maximum likelihood problem, where we estimate the parameters of the dynamical system generating the data by solving the corresponding optimis...

Gear transmission systems constitute a key component in a multitude of applications such as transportation, manufacturing, industry, etc. As such, dynamic analysis of such systems is a powerful tool during the design and operation of machinery incorporating geared connections. Gear transmission syst...

This work studies a computational approach aimed at establishing equivalent dynamical responses within oscillatory impacting systems subject to soft and rigid constraints. The proposed method incorporates an adaptive differential evolution algorithm with the Metropolis criterion to determine the sti...