Sound Simulation Research Articles

Contribution of machine learning and physics-based sound simulations for the optimization of brass instruments

Sound simulations by physical model are interesting to transcribe the physics underlying the functioning of a musical instrument. These simulations make it possible to create virtual sounds with a mode of operation representative of the interaction musician/instrument (driving a sound by the causes that create it). The work consists in studying the contribution of machine learning (ML) methods in the optimization of a musical instrument. The application concerns the brass instruments (trumpets). From a training set of virtual instruments, ML methods are trained to model the intonation (represented by the equivalent fundamental pitch) and the ease of emission (represented by the threshold pressure obtained by linear stability analysis) of sounds, according to the modal parameters of the input impedance. With the ML models, an optimization with genetic algorithms is next carried out to improve the intonation and the ease of emission. The last stage of the approach consists in the optimization of the bore of the instrument (optimization of the shape of the leadpipe). The results show that the approach gives promising results: optimal instruments are actually efficient when re-simulated with the physical model. The manufacturing of an optimal instrument is in progress to confirm the validity of the approach

Validation measurement of vehicle pass-by models for dynamic urban environments

Simulation and auralization of urban traffic noise can help city planners and residents to improve existing urban areas or plan new attractive living spaces while enabling discussions about shared auditory experiences, regardless of expertise. Evaluating street noise in the context of urban areas requires careful consideration of their urban surroundings, such as landscapes, buildings, and other structures. Obtaining measurements to validate simulations may be difficult given the variety and complexity of sounds within an urban setting. Recreating the real urban scenario on a test track, e.g., including building facades and exact source and receiver positions, helps validate simulations but also poses challenges due to varying road surfaces, weather conditions, and disturbances such as industrial or fly-over sounds. This research represents a method of bringing a measurement set-up consisting of source (e.g., vehicle), receiver (e.g., pedestrian), and surfaces (e.g., walls) to the more controlled environment of a hemi-anechoic chamber. The method is intended for the validation of previous vehicle pass-by measurements by utilizing sine sweeps with walls parked at varying distances. These environments aim to deliver more insight into the relevance of diffracted sound for configuration of urban sound simulation models.

Time-dependent dynamical energy analysis via convolution quadrature

Dynamical Energy Analysis was introduced in 2009 as a novel method for predicting high-frequency acoustic and vibrational energy distributions in complex engineering structures. In this paper we introduce the first time-dependent Dynamical Energy Analysis method. Time-domain models are important in numerous applications including sound simulation in room acoustics, predicting shock-responses in structural mechanics and modelling electromagnetic scattering from conductors. The first step is to reformulate Dynamical Energy Analysis in the time-domain by means of a convolution integral operator. We are then able to employ the Convolution Quadrature method to provide a link between the previous frequency-domain implementations of Dynamical Energy Analysis and fully time-dependent solutions by means of the Z-transform. By combining a modified multistep Convolution Quadrature approach for the time discretisation, together with Galerkin and Petrov-Galerkin methods for the space and momentum discretisations, respectively, we are able to accurately track the propagation of high-frequency transient signals through phase-space. The implementation here is detailed for finite two-dimensional spatial domains and we demonstrate the versatility of our approach by performing a range of numerical experiments for regular, non-convex and irregular geometries as well as different types of wave source.

A methodology to restrict the range of motion of joints: Application to the ankle joint complex

One of the most critical aspects when developing biomechanical models is the formulation of the joints, which, in the case of the human body, have limited range of motion (RoM). Thus, restrictions to prevent joints from performing unacceptable movements and avoid unrealistic configurations of the adjacent bodies must be formulated. This study extends the authors’ previous work to demonstrate the potential of applying a methodology to restrict the RoM of joints to the complex case of the human ankle joint complex. The methodology applies joint resistance moments to the adjacent bodies to mimic the resistive and dissipative behavior of the constituent materials and to prevent unacceptable configurations of those bodies. A detailed description of the application of the methodology to the ankle joint complex is given, including the definition of the joint's local reference frames and circumduction cones, estimation of the longitude and latitude, calculation of the maximum latitude using the elliptical approach and the transfer of forces and moments to the adjacent bodies. The methodology correctly restricts the RoM of the ankle joint complex, producing physiologically sound simulation results.

Extraordinary stability of surfactant‐free bubbles suspended in ultrasound

AbstractGravity‐induced drainage is one of the main destabilizing mechanisms for soap bubbles and foams. Here we show that solely through acoustic levitation without introducing any chemical stabilizers, liquid drainage in the bubble film can be completely inhibited, therefore leading to a significant enhancement of bubble lifetime by more than two orders of magnitude and enabling the bubble to survive puncturing by a needle. Based on sound simulation and force analysis, it has been found that acoustic radiation force, exerted on both the inner and outer surfaces of the levitated bubble, acts in opposite directions, thus providing a squeezing effect to the bubble film. The hydrostatic pressure that induces drainage has been balanced by the acoustic radiation pressure exerted on both sides of the film, which is at the origin of the sound stabilization mechanism. This study provides new insights into the interplay between sound and soap bubbles or films, thus stimulating a wide range of fundamental research concerning bubble films and expanding their applications in bio/chemical reactors.

A Conceptual Framework for Immersive Acoustic Auralisation: Investigating the Key Attributes

In architectural acoustics, the assessment of sound propagation in interior and/or environmental conditions has now become progressively more prominent throughout the past few decades, as a response to the development of advanced prediction tools. Within the adaptation of virtual reality (VR) systems, it is necessary to considerably expedite the prediction and simulation software as well as to enable flexible and responsive data analysis during simulation and 3D audio sensory projection. To generate ideal immersion in a simulated virtual environment, the generated stimulus across all senses should therefore be coherent. Accordingly, in the domain of acoustic in virtual reality, the system sound simulation must be constructed efficiently in order to convey the auditory stimuli to the user in an appropriate manner. This necessitates the implementation of virtual reality system as an advanced prediction tool that can accurately anticipate and replicate realistic audio experiences. Therefore, this study explores the realm of acoustic virtual reality (AVR) through a critical review with the purpose of elucidating design attributes and determining factors in generating immersive acoustic VR experiences. In light of these findings, the aim of this paper is to develop a comprehensive conceptual framework that will serve as a beneficial guide and road map for future researchers and developers in the field.

Diving into the virtual realm: Exploring the mechanics of virtual reality

Virtual reality (VR) is a burgeoning technology that aspires to create an immersive digital experience for its users. This essay aims to explore how VR works by inspecting its hardware and software components, as well as the integration of both. The hardware components include the head-mounted display (HMD) with display screens, lenses, and motion tracking sensors for generating visual output and detecting head movements; Input devices, such as hand controllers, enable user interaction. The software components involve 3D computer graphics and rendering techniques, which allow the creation of virtual objects and environments. Real-time rendering ensures smooth and responsive visuals, while audio processing and sound simulation promote a realistic auditory experience. Integrating hardware and software components concerns real-time tracking and synchronization, recognizing and matching user movements with the virtual environment, and ensuring accurate interactions. Feedback mechanisms, especially haptic feedback like vibrations, enhance immersion. Understanding the workings of VR provides insights into its potential applications and its ability to transport users to virtual worlds.

Acoustic Design of Elliptical Bells for Chime Sound Simulation

This project seeks to unravel the opulent acoustical characteristics and sonic effects of ancient Chinese chime bells. Initially, distinctive features of the chime bells are encapsulated, highlighting the bifonic phenomenon and elucidating the role of fundamental and harmonic frequencies in chime bell sound production, while emphasizing the timbral diversity attributable to its multifrequency sound source. An exploration into the impacts of various factors on chime bell sound, such striking position, is conducted through experimentation with a bronze chime bell model, underscoring their significant influence. Employing experimental modal analysis methods, vibrational modes of the chime bell surface at disparate frequencies are revealed, laying a foundation for understanding the sound production principles. Furthermore, image processing technologies are utilized to construct a 3D model of the chime bell, and finite element modal analysis methods are applied to visualize its modes. The feasibility of using a circular ring to simulate chime bell sound is explored, identifying the elliptical ring as a more promising option and undergoing numerous rounds of iterative optimization. The theoretical research is brought to fruition by manufacturing a cast iron elliptical ring model for striking experiments, thereby validating the theoretical insights. In summation, this research provides a comprehensive and systematic exploration into the acoustical mechanisms and design principles of chime bells, offering invaluable insights into ancient Chinese music and cultural heritage. The multi-faceted and rich nature of chime bells as musical instruments is unveiled through the integrated application of various methods, deepening the understanding of their acoustical characteristics.

Real-time counting of wheezing events from lung sounds using deep learning algorithms: Implications for disease prediction and early intervention.

This pioneering study aims to revolutionize self-symptom management and telemedicine-based remote monitoring through the development of a real-time wheeze counting algorithm. Leveraging a novel approach that includes the detailed labeling of one breathing cycle into three types: break, normal, and wheeze, this study not only identifies abnormal sounds within each breath but also captures comprehensive data on their location, duration, and relationships within entire respiratory cycles, including atypical patterns. This innovative strategy is based on a combination of a one-dimensional convolutional neural network (1D-CNN) and a long short-term memory (LSTM) network model, enabling real-time analysis of respiratory sounds. Notably, it stands out for its capacity to handle continuous data, distinguishing it from conventional lung sound classification algorithms. The study utilizes a substantial dataset consisting of 535 respiration cycles from diverse sources, including the Child Sim Lung Sound Simulator, the EMTprep Open-Source Database, Clinical Patient Records, and the ICBHI 2017 Challenge Database. Achieving a classification accuracy of 90%, the exceptional result metrics encompass the identification of each breath cycle and simultaneous detection of the abnormal sound, enabling the real-time wheeze counting of all respirations. This innovative wheeze counter holds the promise of revolutionizing research on predicting lung diseases based on long-term breathing patterns and offers applicability in clinical and non-clinical settings for on-the-go detection and remote intervention of exacerbated respiratory symptoms.

A Study on Mechanical Behavior of Intact Granite Through a Sound Simulation Using Flat-Jointed Contact

A Study on Mechanical Behavior of Intact Granite Through a Sound Simulation Using Flat-Jointed Contact

Art Is Magic

Art Is Magic

Improved Water Sound Synthesis using Coupled Bubbles

We introduce a practical framework for synthesizing bubble-based water sounds that captures the rich inter-bubble coupling effects responsible for low-frequency acoustic emissions from bubble clouds. We propose coupled-bubble oscillator models with regularized singularities, and techniques to reduce the computational cost of time stepping with dense, time-varying mass matrices. Airborne acoustic emissions are estimated using finite-difference time-domain (FDTD) methods. We propose a simple, analytical surface-acceleration model, and a sample-and-hold GPU wavesolver that is simple and faster than prior CPU wavesolvers. Sound synthesis results are demonstrated using bubbly flows from incompressible, two-phase simulations, as well as procedurally generated examples using single-phase FLIP fluid animations. Our results demonstrate sound simulations with hundreds of thousands of bubbles, and perceptually significant frequency transformations with fuller low-frequency content.

Estimation of fused-filament-fabrication structural vibro-acoustic performance by modal impact sound

Accurately simulating and designing the vibro-acoustic performance of 3D printed structures is a challenging task due to the lack of material elastic properties, particularly when designing without specialized measurement instruments. To tackle this issue, we propose a numerical-experimental estimation method based on modal impact sound, which only requires a microphone for measurement. Specifically, we established a modal impact sound simulation pipeline that considers the material anisotropy and estimated the material elastic property by minimizing the residuals between the simulated and recorded modal impact sound features. Our method outperforms the state-of-the-art modal-sound approach in terms of convergence speed and accuracy, and achieves an average modal-frequency residual of 0.66% across two materials and six infills. We also designed and manufactured a xylophone using the estimated material elasticity for further demonstration and verification.

The Influence of Contextual Non-Auditory Factors on Drone Sound Perception

New forms of air transport are expected to arrive in the next decade: development of unmanned multi-rotor equipped drones, are expected to be used for not only observation purposes, but for postal package delivery as well. The impact of close-flying drones near communities is still not fully understood. One of the main concerns for public acceptability is noise impact as it may negatively affect human health and well-being. Prior research shows that non-acoustical factors play an important role in the perception of noise. A laboratory study was conducted to evaluate different subjective factors to examine their influence on noise annoyance: education on useful applications of drones (positive framing), rural versus urban environments, different visually modelled sizes of drones, and the visual noticeability of drones. Participants of the study evaluated scripted drone events using a Virtual Reality headset with a sound simulation system. Results show that drones flying in a rural environment were perceived as significantly louder, more annoying, and more noticeable compared to an urban setting. Also, noticeability of a drone significantly predicted annoyance and loudness. However, the size of the drone influenced noticeability, but not annoyance. Unexpectedly, the positive framing did not have a measurable influence in this study.

Numerical Inversion of the Sumudu Integral Transform in the Simulation of Electromagnetic Sounding of the Earth’s Interior

Abstract —The integral Sumudu transform was established as an alternative to the Laplace transform in the 1990s. The Sumudu transform fundamental properties include preservation of the dimensionality of a function, ensuring measurement units both in the function and its image to be equivalent. Among its disadvantages is the absence of an explicit formula for calculating the inverse transform. The transforms are inverted by solving the corresponding Fredholm integral equation of the first kind, which is reduced to solving an ill-conditioned system of linear algebraic equations. We apply Tikhonov’s method for regularization of this type system. The paper proposes a technique for constructing a parametrized regularizing matrix that takes into account the properties of the Sumudu images obtained by modeling the electromagnetic sounding process of the Earth’s interior. A method for choosing the Tikhonov regularization parameters and the regularizing matrix is considered. The effectiveness of the proposed method for the Sumudu transform inversion is examined on a model problem of electromagnetic sounding of the Earth’s interior by a measurement system consisting of two loops spaced apart.

Research on the Application of Sound in Virtual Reality

Immersive sound is an essential element of any Virtual Reality (VR) experience. In recent years, increasing popularity of VR devices and numerous advancements in hardware and software technologies, the development of immersive interactive sound has become more potent. This article explores VR through the sonic perception, presents a review of the Method of combining and applying sound and VR, with the goal of providing more references and suggestions for the sound of VR. This includes the creative and technical work of music and spatial sound in practical projects in recent years. Some examples of musical VR are provided in this article to compare their characteristics. A review of the state of the art of sound simulations, focusing on the various factors that ensure a complete and immersive audio experience, while trying to strike an appropriate balance between realism and accuracy. This article finally discusses the future and challenges of sound in VR.

A virtual reality tool to aid in soundscapes in the built environment (SiBE) through machine learning

Regarding the function and context of the space, virtual reality (VR) can be used for soundscapes design if the user behavior is predictable. This study enables the acoustic characterization of VR development tools to measure auditory perception based on user behavior. The research question is whether soundscapes can be modeled according to the variable acoustic environments defined by the existing architectural features (e.g., prismatic, courtyard, vault, arched, mezzanine). A sound simulation algorithm in MATLAB was developed to extract room impulse response (RIR) of the test environment in a virtual environment and to compare it with the real environment (RE). In the developed program, image source model (ISM) and ray trace were used to be performed the real-time acoustic source generation and real-time signal recording, image functions, data processing, metric calculation operations (e.g., tonality and spectrogram). B&K 4292 omni-power loudspeaker, B&K 2716 power amplifier, and B&K 2250 hand-held analyzer were used to measure RIR in the RE. In addition to RIR and RT30, psychoacoustic metrics (e.g., loudness, sharpness, roughness, and fluctuation strength) were measured in both environments. The results showed that sound simulation, based on ISM, demonstrates the validity and can be used for the acoustic characterization of VR development environments.

Design of a low frequency, impulsive sound simulator in an existing house for sonic boom perceptual studies

The renewal of civil supersonic aviation is partly conditioned by the establishment of an international regulation on sonic boom level. Human perception of booms from future aircraft creating sound disturbances of lower level than past ones can currently be evaluated only through boom simulators in laboratory setups with predicted signatures from numerical simulations. To reach sufficient ecological validity, it is necessary that perception studies take place in an environment as familiar as possible to participants. With this in view, a simulator has been designed to reproduce sonic booms of low amplitude with the highest possible fidelity and control, while adapting to an existing house. The article presents the challenges and design solutions chosen to reach this objective. A double optimisation of the input signal, successively in the frequency and in the time domain, is described. Observed performances are presented for different boom exposures and in various rooms of the house.

Research on the Design Method of Pure Electric Vehicle Acceleration Motion Sense Sound Simulation System

Due to the emerging trend of energy conservation and emission reduction around the world, the new energy vehicle industry has achieved rapid development. However, there are new challenges regarding vehicle NVH(noise, vibration, and harshness). When a pure electric vehicle is being driven, the inside of the vehicle is relatively quiet, which cannot bring the driver sound feedback reflecting the change of the vehicle state. In order to solve this problem, this paper studies the design method of a sound simulation system for acceleration motion in pure electric vehicles. In this paper, the motion characteristics of automobile engine acceleration sound, sound signal analysis and processing, subjective evaluation of sound quality, and sound synthesis strategy are studied. By reading the vehicle running state data on the CAN bus of pure electric vehicles, the goal of engine motion sense sound simulation during vehicle acceleration is achieved. This helps to enhance driving feedback and improve user driving experience.

Interactive soundscape simulation as a co-design tool for urban professionals

Urban professionals are regularly confronted with the complexity of urban sound experiences and have long expressed interest in better sound design opportunities. But, in many urban environments, the common approach based on noise mitigation has proven insufficient to improve the quality of the auditory experience. However, urban professionals rarely have the resources and knowledge to deal with urban sound in a resource-centered manner and to make space for perceptual and contextual suitability for a diversity of experiences. To start bridging this gap, the present research explores the potential of a soundscape simulator prototype to help integrate sound into the urban design process. Through a formative evaluation with urban professionals during an interactive workshop, this study reveals avenues for the development of a simulation tool for urban professionals, including the need to balance flexibility and accuracy, to present changes in real time, and to seamlessly switch between different compositions to support design comparisons. Our findings also hint at a shift away from the visual-centeredness and a willingness amongst urban professionals to consider a more holistic urban sensory experience. We conclude with recommendations for a sound simulation tool for urban planning.