Applied Acoustics Research Area

Have you ever paused to listen to the sounds around you? The rustling leaves, the distant hum of traffic, or the soothing rhythm of ocean waves? These everyday sounds form our acoustic environment, and they play a crucial role in shaping our well-being. Acoustics, the science of sound, goes far beyond concert halls and musical instruments. It touches every aspect of our lives, from urban planning and architecture to health and communication.

A room with walls covered in brown cardboard with a test dummy on the floor — The anechoic chamber at Applied Acoustics

Acoustics deals with sound and vibration which are a fundamental part of our daily life. Auditory stimuli and vibrations deliver a substantial stream of information from the outer world. The discipline acoustics is highly interdisciplinary and comprises numerous subdisciplines. These subdisciplines are grouped around the fundamentals of acoustics containing the basic physics of wave generation and wave propagation in different media. The subdisciplines also represent the link to other disciplines inside Earth science, Life science, Arts and Engineering as shown in Lindsay’s “acoustic wheel” published 1964 in the Journal of the Acoustical Society of America.

All our work revolves around the human experience of sound. Noise is identified by the WHO as second biggest environmental burden after air pollution in western Europe. It is essential that our acoustic outdoor as well as indoor environment support health and wellbeing of people at the same time lead to a sustainable built environment.

Our research

The mission of the research area Applied Acoustics at Chalmers is to create and preserve healthy and sustainable environments as well as to support the development of products and services with appropriate sound and vibration properties. The main areas in focus is the transport systems (road and rail), our living environment with special focus on the urban space and housing and the development of tools and methods to create virtual acoustic environments.

Transportation noise

The research area Applied Acoustics has a strong focus on the reduction of the negative impact of sound and vibrations from road and rail traffic on people’s health and wellbeing. For this, the understanding and prediction of rolling and squealing noise from wheel/rail systems as well as rolling noise from tyre/road interaction is needed. This includes advanced modelling of the dynamic behaviour of the involved structures (for example railway tracks) as well as of the complex interaction between wheel and track and tyre and road.

Today, the rolling models developed at Chalmers have reached a quality allowing for the development of approaches for acoustic monitoring of railway tracks. Such emerging approaches are essential for infrastructure owners to decide on grinding schemes for rails (for example to reduce noise) as well as to ensure structural health of track and wheels. The rolling noise models also approach a quality that allows for plausible auralisation of sound from rail/wheel or tyre/road interaction. By creating virtual environments, focus is put on perception-based design of wheel/track and tyre/road systems.

Built environment

The acoustic properties of urban space and indoor environments should support well-being and health of people living in these environments. Our research is focused on the planning of urban space including traffic management, urban form, the use of greenery for reducing noise and air pollution, the reduction of ground-borne noise and vibration or on the acoustic consequences of the transition from combustion engines to electric vehicles and more.

The use of wood as building material demands care in the design of buildings to ensure a healthy acoustic environment indoors. This especially concerns the low frequency sound insulation challenges that arise in wooden buildings. In all these aspects, the perception of sound and vibration by humans are in the centre. Auralisation techniques are used to create virtual environments to allow for perception-based design of outdoor and indoor environments such as open plan offices or dwellings.

Auralisation

A significant amount of research is hampered because state-of-the-art auralisation methods are limited in their fidelity. Examples for such research are the human response to complex sound scenes such as open-space offices or the development and evaluation of signal processing algorithms in hearing aids that require exposure to controlled complex sound scenes. It is not to be expected that the one universal auralisation method will be available any time in the foreseeable future that will fulfill the requirements of all deployment scenarios.

We therefore strive to increase the flexibility of auralisation methods so that they can be optimized for the specific requirements of each deployment scenario. This will enable not only practical applications but also a variety of research that uses auralisation as a tool. On-going projects cover, for example, signal processing methods for the auralisation of room acoustic simulations, microphone array systems for perceptually transparent capture of sound scenes, and signal processing methods for manipulating captured sound scenes.