Soil Vibration and Auralisation Software Tools for Application in Railways (SILVARSTAR)
The overall goal of SILVARSTAR is to provide the railway community with proven software tools and methodologies to assess the noise and vibration environmental impact of railway traffic on a system level. The first overall objective of SILVARSTAR is to provide the railway community with a commonly accepted, practical and validated methodology and a userfriendly prediction tool for ground vibration impact studies. This tool will be used for environmental impact assessment of new or upgraded railways on a system level. It will provide access to ground vibration predictions to a wider range of suitably qualified engineers and will facilitate project planning and implementation by improved simulation processes.
The second overall objective of SILVARSTAR is to develop a fully functional system for auralisation and visualisation based on physically correct synthesised railway noise, providing interfaces with Virtual Reality visualisation software. This system will facilitate communication with the public, decision makers and designers through virtual experience before delivery of projects.
Empa is responsible for the second overall objective of SILVARSTAR and leads the corresponding work package and conducts the major work on the development of a fully functional system for auralisation of railway noise.
Contact: Reto Pieren
Funding: Horizon 2020, Shift2rail
Partner: Empa, University of Southampton, KU Leuven, VibraTec, Wölfel, unife, Bandara VR
Duration: 2020 - 2022
Publications: Pieren, R., Georgiou, F., Squicciarini, G., & Thompson, D. J. (2022). Auralisation of combined mitigation measures in railway pass-by noise. In Proceedings. Internoise 2022 (p. 518 (9 pp.). Internoise.
Bouvet, P., Degrande, G., Thompson, D., Pieren, R., & García, M. (2021). Silvarstar project: soil vibration and auralisation software tools for application in railways. Global Railway Review, 27(6), 6-9.
Pieren, R., Georgiou, F., Thompson, D., Heutschi, K., Squicciarini, G., Rissmann, M., & Bouvet, P. (2021). Methodology for auralisation and virtual reality of railway noise. SILVARSTAR Consortium.
Pieren, R., Georgiou, F., Squicciarini, G., Heutschi, K., & Thompson, D. J. (2023). VR demonstration of railway noise mitigation using auralised train pass-bys. In Forum Acusticum 2023. Convention of the European Acoustics Association (p. (7 pp.). The European Acoustics Association (EAA).
Bouvet, P., Thompson, D., Pieren, R., Degrande, G., Nuber, A., & Garcia, M. (2023). Soil vibration and auralisation software tools for application in railways. In L. de Picado Santos, J. Pinho de Sousa, & E. Arsenio (Eds.), Transportation research procedia: Vol. 72. TRA Lisbon 2022 conference proceedings transport research arena (TRA Lisbon 2022) (pp. 973-980). https://doi.org/10.1016/j.trpro.2023.11.525

ARTEM - Aircraft noise Reduction Technologies and related Environmental iMpact
With ARTEM (Aircraft noise Reduction Technologies and related Environmental iMpact), seven EREA members and strategic partners have teamed up with leading European universities and major entities of the European aerospace industry in order to address the technology challenges raised in the call MG-1-2-2017 “Reducing aviation noise”. ARTEM aims at the maturing of promising novel concepts and methods which are directly coupled to new low noise and disruptive 2035 and 2050 aircraft configurations. A core topic of ARTEM is the development of innovative technologies for the reduction of aircraft noise at the source. The approach chosen moves beyond the reduction of isolated sources as pure fan or landing gear noise and addresses the interaction of various components and sources - which often contributes significantly to the overall noise emission of the aircraft. Secondly, ARTEM addresses innovative concepts for the efficient damping of engine noise and other sources by the investigation of dissipative surface materials and liners. The chosen technology concepts offer the chance to overcome shortcomings (as the narrow band absorption peak or poor low-frequency performance) of current devices. The tasks proposed will mature, and subsequently down select these technologies by comparative testing in a single relevant test setup. Furthermore, noise shielding potential for future aircraft configurations will be investigated. The noise reduction technologies will be coupled to the modelling of future aircraft configurations as the blended wing body (BWB) and other innovative concepts with integrated engines and distributed electrical propulsion. The impact of those new configurations with low noise technology will be assessed in several ways including industry tools, airport scenario predictions, and auralization. Thereby, ARTEM constitutes a holistic approach for noise reduction for future aircrafts and provides enablers for the expected further increase of air traffic.
Contact: Reto Pieren
Project partners: DLR, AEDS, Airbus, CIRA, CNRS, Comoti, Dassault, EC Lyon, EPFL, ONERA, INCAS, PPS, RRD, SAE, SOTON, TSAGI, TUBS, TUDelft, UBristol, UCP, URoma3, VKI
Project funding: EU – Horizon 2020
Duration: 2017 – 2022
Publications: Schäffer, B., Bertsch, L., Le Griffon, I., Heusser, A., Lavandier, C., & Pieren, R. (2022). Evaluation of flyover auralisations of today's and future long-range aircraft concepts. In Proceedings. Internoise 2022 (p. 571 (8 pp.). Internoise.
Pieren, R., & Lincke, D. (2022). Auralization of aircraft flyovers with turbulence-induced coherence loss in ground effect. Journal of the Acoustical Society of America, 151(4), 2453-2460. https://doi.org/10.1121/10.0010121 
Rizzi, S., LeGriffon, I., Pieren, R., & Bertsch, L. (2020). A comparison of aircraft flyover auralizations by the aircraft noise simulation working group. In AIAA aviation 2020 forum (pp. AIAA 2020-2582 (16 pp.). https://doi.org/10.2514/6.2020-258
Pieren, R., Le Griffon, I., Bertsch, L., Heusser, A., Centracchio, F., Weintraub, D., … Schäffer, B. (2024). Perception-based noise assessment of a future blended wing body aircraft concept using synthesized flyovers in an acoustic VR environment - The ARTEM study. Aerospace Science and Technology, 144, 108767 (19 pp.). https://doi.org/10.1016/j.ast.2023.108767
Pieren, R., Le Griffon, I., Bertsch, L., Heusser, A., Centracchio, F., Weintraub, D., … Schäffer, B. (2024). Perception-based noise assessment of a future blended wing body aircraft concept using synthesized flyovers in an acoustic VR environment - The ARTEM study. Aerospace Science and Technology, 144, 108767 (19 pp.). https://doi.org/10.1016/j.ast.2023.108767

Experimental and numerical track system evaluation: Methodology for finding optimal components (Track Evaluation)
In recent years, many new components have been developed to decrease railway noise radiation, mitigate ground vibrations, and reduce track maintenance costs by protecting the ballast. Today, railway infrastructure managers are facing the challenge to evaluate and select the best components available for its future railway implementations and renewal.
However, due to the large number of combinations and the amount of time and work required to evaluate each potential solution, there is a critical need to be able to evaluate and preselect components more efficiently, using simpler lab scale measurements to characterize the components combined with numerical models to estimate multiple track performance criteria.
Based on the work undertaken previously in the Novel Rail Pad project, the goal of this project is i) to develop a combined experimental & numerical evaluation method to provide a prognosis of different track component combinations in terms of their performance for noise, vibrations and ballast protection and ii) use these prediction tools to explore the design space of component properties to identify the best combination of components to match a given performance target and thus allow railway infrastructure managers to formulate detailed system specifications in their procurements.
Contact: Bart Van Damme
Partner: HEIG-VD
Project funding: FOEN
Duration: 2022 - 2023

Expansion of the acoustic source database for civil aircraft of sonAIR - AirCLOUD

Three objectives are pursued in the project AirCLOUD:
1) Acoustic emission models of recently introduced aircraft types will be created based on measurements at Zurich Airport. On this basis, the emission database of the aircraft noise model sonAIR – as well as FLULA2 – will be updated.
2) Aircraft noise calculations with sonAIR require information on thrust setting and, where available, configuration of the aircraft. However, this information is usually not accessible. Using machine learning approaches and training data provided by Swiss, a methodology is being developed to estimate these parameters for situations in which only radar data is available.
3) In addition to the machine learning approaches, a methodology will be developed to directly determine the engine speed from pure tone components in sound recordings.
Contact: Jean Marc Wunderli
Partners: Swiss International Airlines, Flughafen Zürich AG
Project funding: FOCA
Duration: 2021 – 2023
Publications: Ramseier, T., & Pieren, R. (2023). Estimation of the fan rotational speed using flyover audio recordings. Journal of Aircraft. https://doi.org/10.2514/1.C037371
Meister, J. (2023). Thrust estimation for departing jet aircraft using position data based on a machine learning approach. In Forum Acusticum 2023. Convention of the European Acoustics Association (p. (5 pp.). The European Acoustics Association (EAA).

DD-FORMS: Data-driven fast optimization of resonant metamaterial structures
In recent years, resonant metamaterials have garnered much interest because of their potential to break with traditional design principles in noise and vibration management. By virtue of a carefully designed micro- or mesostructure, metamaterials display exotic macroscopic properties, such as vibrational band gaps, that do not exist in known bulk materials. However, modeling and optimizing these emergent properties is a challenging multiscale problem. The process remains computationally intractable in many cases due to the heavy reliance on expensive finite-element analyses and/or topology optimizations.
To address this challenge, the present project focuses on applying data science techniques in the design of resonant metamaterial structures. In particular, we target vibration reduction in finite-sized elastic plates by integrating 3D-printed mechanical resonators, which is treated as an optimization problem in both the arrangement and the dynamics of the resonators. Where possible, costly high-fidelity simulations and optimizations will be replaced with data-driven surrogates to drastically reduce the computational load. On the one hand, the inverse design problem of creating resonators with a desired dynamic response will be addressed, for instance by applying tandem neural networks. On the other hand, we will investigate the optimal arrangement of resonators for maximum vibration reduction. Here, Bayesian optimization techniques may offer an efficient solution. The range of material and geometric properties obtainable via the 3D-printing process will be identified and taken into account.
Contact: Bart Van Damme
Funding: SDSC
Partner: SDSC, Laboratory for Advanced Materials Processing (Empa)
Duration: 2021 - 2023

Acoustic Characterization of fungi-treated Violins
How does a fungi-treatment of the tone-wood affect the acoustic properties of violins? An experimental investigation of the structure-borne and the radiated sound fields of different violins – treated and untreated – is performed in the anechoic laboratories. A subsequent psycho-acoustic investigation focusses on the perception and endeavors to single out significant acoustic properties of the individual instruments.
Contact: Reto Pieren
Partner/Funding: Fischli-Stiftung, Allschwil, CH
Duration: 2017 – 2023

Novel Rail Pads for Improved Noise Reduction and Reduced Track Maintenance
The goal of the project is to develop a novel rail pad system that is optimized with respect to both railway noise reduction and protection of the railway superstructure against transient loads and vibrations. The desired property profile of the novel rail pad cannot be obtained with existing materials, but requires tailoring of the structure and function of the rail pad system at multiple levels and length scales.
We will complement experimental methods with state-of-the-art modelling in order, for the first time, to establish rigorous structure-property relationships, and provide detailed guidelines for combined materials selection and device geometry optimization.
Contact: Bart Van Damme
Partners: École polytechnique fédérale de Lausanne EPFL (LMOM, LPAC, LMAF, LTS2, TRACE), SBB
Funding: FOEN
Duration Phase I: 2017 – 2019
Duration Phase II: 2020 - 2023
Publication: Balamonica, K., Morin, B., Plummer, C. J. G., Michaud, V., Cugnoni, J., Oertli, J., … van Damme, B. (2022). Characterization of contact parameters for discrete element modelling of Swiss railway ballast. In The fifth international conference on railway technology: research, development and maintenance (p. (6 pp.). Elsevier.
Morin, B., Plummer, C. J. G., Kalyanasundaram, B., Michaud, V., Cugnoni, J., Oertli, J., … Van Damme, B. (2022). A fast analytical tool to investigate effects of railway superstructure components on track dynamics. In The fifth international conference on railway technology: research, development and maintenance (p. (5 pp.). Elsevier.
Balamonica, K., Bergamini, A., & Van Damme, B. (2023). Estimation of the dynamic stiffness of railway ballast over a wide frequency range using the discrete element method. Journal of Sound and Vibration, 547, 117533 (13 pp.). https://doi.org/10.1016/j.jsv.2022.117533

Impact sound insulation of solid wood floors with acoustic black hole (TriMASL)
Use of so-called "acoustic black holes" to improve the impact sound insulation in solid wood floors. This reduces the mass of floor toppings that was previously necessary for sound-insulation, thus further expanding the technical and economic advantages of timber construction. The aim of the investigation is the development of design and optimization methods and the implementation of a technology de-monstrator.
Contact: Stefan Schoenwald
Project funding: BAFU
Duration: 2019 - 2022
Publication: Schoenwald, S. (2022). Planungstools aus der Schweiz. In Forum Holzbau (2022): Forum Holzbau 6. Internationale Fachtagung Bauphysik & Gebäudetechnik (BGT). Holzbau/Trockenbau/Innenausbau (p. (10 pp.). Forum-holzbau (fhb).
Vallely, S., & Schoenwald, S. (2023). An efficient analytical method to obtain the homogenised frequency-independent elastic material properties of cross-laminated timber elements. Journal of Sound and Vibration, 546, 117424 (24 pp.). https://doi.org/10.1016/j.jsv.2022.117424
Schoenwald, S., & Vallely, S. (2023). Cross laminated timber elements with functional grading and localised ballast to improve airborne and impact sound insulation. In Forum Acusticum 2023. Convention of the European Acoustics Association (p. (6 pp.). The European Acoustics Association (EAA).

Optimized high-lift system for low noise approaches, including best configuration for landing (DYNCAT)
DYNCAT aims at enabling more environmentally friendly and more predictable flight profiles in the Terminal Manoeuvring Area TMA, namely on approach, by supporting the pilots in configuration management. Approach and take-off operations at busy airports are virtually always less noise and fuel efficient than possible due very rigid constraints imposed on the flight profiles by Air Traffic Control ATC (concerning both vertical profiles and speed regimes), but also due to lack of support to the pilots for dealing with given restrictions/constraints and actual weather in the optimum way. Current FMS functionalities do not support configuration management very well, only a simplified, static high-lift sequence with a fixed order is available. The adequacy of actual procedure flown depends very much on the pilots' skills, but also on their access to information such as actual wind situation and ATC intents.
The objectives of the project are (a) to analyze the impact of current mismatch of aircraft and ATC procedures on flyability (pilot workload, safety) and environmental impact (fuel burn and CO2; noise), (b) to propose amendments to on-board and ground procedures including identification of necessary enablers (technical, regulatory) and (c) to quantify ecological and economical potential of proposed improvements, including the prediction of 4D Trajectories, through exemplary analysis and early prototype simulation of newly designed configuration management functionality.
The study will be done exemplarily using the A320 family as reference aircraft and the development of new FMS functionalities for the optimization of the high-lift system sequencing during approach as use case. Access to recordings of actual flight operational data, associated ATC instructions issued, weather data and noise measurements for a large number of operations in Swiss airspace on one hand and the implementation of the improved functionalities on an industrial test platform on the other allow for high validity and relevance of the results.
Contact: Jean Marc Wunderli
Funding: Horizon 2020 (SESAR)
Partner: DLR, Swiss Airlines, THALES, SkyLab
Duration: 2020 - 2022
Publication: Abdelmoula, F., Roeser, M. S., Kühne, C. G., Gerber, M., & Wunderli, J. M. (2022). Impact of ATC speed instructions on fuel consumption and noise exposure: an assessment of real operations in Zurich. CEAS Aeronautical Journal. https://doi.org/10.1007/s13272-022-00609-y
Gerber, M., Schreiber, Y., Abdelmoula, F., Kühne, C. G., Jäger, D., & Wunderli, J. M. (2022). Energy-optimized approaches: a challenge from the perspectives of pilots and air traffic controllers. CEAS Aeronautical Journal. https://doi.org/10.1007/s13272-022-00607-0

Urban Mining for Low Noise Urban Roads and Optimized Design of Street Canyons
The soundscape of urban situations is often dominated by road traffic noise. In densely populated areas, noise can cause serious health problems and therefore, city planners are seeking for suitable design strategies to improve the acoustical quality of public spaces.
This SNF funded project aims for a multidisciplinary approach to optimize urban roads and street canyon designs. It is structured in four modules:
1) Development of low noise pavements to improve comfort and health of urban dwellers.
2) Identification of waste materials from the urban environment, for the purpose of producing low noise pavements.
3) Exploration of the noise reduction potential by modification of absorption and reflection properties of the surfaces that form urban street canyons and evaluation of the measures from a subjective point of view by auralisation and listening tests.
4) Improvement and extension of existing methods in Life Cycle Impact Assessment based on the results obtained in module 3).
Contact: Kurt Heutschi
Partner/Funding: Empa Road Engineering / Sealing Components Laboratory, ETHZ Ecological Systems Design, SNF
Duration: 2018 – 2021
Publications: Mikhailenko, P., Piao, Z., Kakar, M. R., Bueno, M., Athari, S., Pieren, R., … Poulikakos, L. (2022). Low-noise pavement technologies and evaluation techniques: a literature review. International Journal of Pavement Engineering, 23(6), 1911-1934. https://doi.org/10.1080/10298436.2020.1830091
Piao, Z., Waldner, U., Heutschi, K., Poulikakos, L. D., & Hellweg, S. (2022). Modified life cycle assessment for low-noise urban roads including acoustics and monetarization. Transportation Research. Part D: Transport and Environment, 112, 103475 (13 pp.). https://doi.org/10.1016/j.trd.2022.103475
Poulikakos, L. D., Athari, S., Mikhailenko, P., Kakar, M. R., Bueno, M., Piao, Z., … Heutschi, K. (2022). Effect of waste materials on acoustical properties of semi-dense asphalt mixtures. Transportation Research. Part D: Transport and Environment, 102, 103154 (14 pp.). https://doi.org/10.1016/j.trd.2021.103154
Athari, S. (2023). A hybrid acoustics simulation of 3D urban street canyon design scenarios with multiple reflections used for auralising a moving sound source [Doctoral dissertation, ETH Zurich]. https://doi.org/10.3929/ethz-b-000607512

Data Science Enabled Acoustic Design – AADS
Projektbeschrieb: https://datascience.ch/project/data-science-enabled-acoustic-design-aads/
Ansprechpartner: Kurt Heutschi
Projekförderung: Swiss Data Science Center
Projektpartner: Swiss Data Science Center, Gramazio Kohler Research - ETH Zürich, Strauss Electroakoustik
Dauer: 2018-2020

Shunted electroactive membrane absorbers (SEMA)
Resonating thin membranes in front of an air cavity are efficient sound absorbers. The frequency of maximum absorption depends on the membranes stiffness, pretension, and geometry. Low frequency sound absorption requires large membranes or thick cavities. Tuning membrane low frequency absorbers is not straightforward. If the membrane's strain generates a voltage, the electromechanical coupling can be used to tune its resonance frequency in a different way. A circuit consisting of the capacitive membrane, a resistor and an inductance gives rise to an electrical resonance, at which the membrane's stiffness is significantly reduced. The electrical eigenfrequency can be easily tuned to any frequency, independent of the tension in the membrane. This project investigates practical ways of achieving high sound absorption using this principle.
Contact: Bart Van Damme
Funding: SNSF
Duration: 2020

Prediction of sound insulation in multi-storey solid wooden construction (SPiMM)
The share of timber construction in multi-storey new buildings is also increasing steadily in Switzerland. A detailed sound insulation calculation has not yet been possible. In order to make noise control pre-dictable, calculation processes are reviewed in this first project phase, taking into account the connec-tions between solid wood components: The applicability of the methods required for the calculation and the availability of the necessary input data are investigate exemplarily at a building junction with rigid connetions.
Contact: Stefan Schoenwald
Project funding: BAFU
Duration: 2020

Development of a calculation tool for a low-noise operation of multicopters
It is becoming apparent that the use of multicopters will increase strongly in the coming years, not only privately but also commercially. Authorization of commercial use must cover not only flight safety aspects but also noise issues. In the present project, a tool is therefore being developed which provides the necessary basis for this. The tool is based on sonAIR, the existing software for calculating aircraft noise. sonAIR will be expanded to allow the planning of operations of commercially used, electrically operated multicopter aircraft and the calculation of the resulting noise pollution. Furthermore, recommendations for low-noise products and noise-reduced operations will be developed, thus contributing to the reduction of noise pollution.
Contact: Jean Marc Wunderli
Funding: FOCA
Partner: ALR, n-Sphere, Meteomatics, Matternet
Duration: 2019 - 2020
Publications: Wunderli, J. M., Meister, J., Boolakee, O., & Heutschi, K. (2023). A method to measure and model acoustic emissions of multicopters. International Journal of Environmental Research and Public Health, 20(1), 96 (17 pp.). https://doi.org/10.3390/ijerph20010096

Implementation of a pilot assisting system for low noise landing procedures at Zurich Airport
This project aims at further developing the pilot assistance system LNAS of the German Aerospace Center DLR, to allow different types of approaches such as Continuous Descent Approach (CDA) respecting the specific environment of Zurich airport (terrain, airspace restrictions, etc.). Taking into account the pilots user requirements, the human-machine interface shall be improved for an intuitive display of the aircraft configuration change and flight mode commands on an approach map. Additionally, the ATC information about the distance to threshold shall be used to optimize the vertical flight profile. In a one-week flight campaign the system will be demonstrated using the DLR Airbus A320 ATRA (Advanced Technology Research Aircraft) with regular airline pilots operating in the Zurich airport environment to reduce noise with optimized approach profiles and aircraft configuration changes. Noise measurements and subsequent single flight simulations with sonAIR based on FDR data will be conducted by EMPA to analyze the potential of this pilot assistance system. An operational trial with LNAS on aircrafts of Swiss Airline and related 3-month noise measurements is an option of this project.  Industrialization of LNAS is the long-term goal after successful demonstration.
Contact: Jean Marc Wunderli
Partner/Funding: SkyLab, DLR, Zurich Airport, skyguide, Swiss Airlines, Swiss Air Force / FOCA, Office of Transport of the Canton of Zurich (AFV)
Duration: 2018 – 2020
SRF-Beitrag "Schweiz aktuell" vom 10.9.2019

CompenSENSE
Currently the Federal Noise Abatement Commission discusses in the context of a harmonization of noise abatement and land-use planning regulations the following questions: Are negative effects of traffic noise reduced in the presence of local recreational areas? If yes, could an installation or upgrading of such recreational areas be seen as a noise mitigation measure?
FOEN advised Empa to investigate these questions by reanalysing the survey sample dataset of the SiRENE study. To that purpose additional information on general properties, distance and accessibility of recreational areas should be collected and combined with the present dataset.
Contact: Jean Marc Wunderli
Partner/Funding: FOEN
Duration: 2018 – 2020
Publication: Schäffer, B., Brink, M., Schlatter, F., Vienneau, D., & Wunderli, J. M. (2020). Residential green is associated with reduced annoyance to road traffic and railway noise but increased annoyance to aircraft noise exposure. Environment International, 143, 105885 (13 pp.). https://doi.org/10.1016/j.envint.2020.105885

SILENTIUM
Mandated by FOEN, Empa is trying to elucidate the role of single noise events and quiet interim phases on annoyance, based on unfocussed listening tests. The results shall be used to discuss whether future rating levels for traffic noise shall solely rely on average levels such as Leq or if they should be complemented by additional correction factors like the number of pass-bys.
Contact: Jean Marc Wunderli
Partner/Funding: FOEN
Duration: 2018 – 2020
Publication: Schäffer, B., Taghipour, A., Wunderli, J. M., Brink, M., Bartha, L., & Schlittmeier, S. J. (2022). Does the macro-temporal pattern of road traffic noise affect noise annoyance and cognitive performance? International Journal of Environmental Research and Public Health, 19(7), 4255 (24 pp.). https://doi.org/10.3390/ijerph19074255

Schallabsorption von Wandpanel-Unikaten
Es wurden schallabsorbierende Wandpaneele entwickelt, welche massgeschneidert in den Kontext der Raumarchitektur und der Ästhetik eingepasst werden können - individuell entworfen und produziert (handgewoben). Dabei konnte eine hohe Schallabsorption erreicht werden, und es zeigte sich, dass unter Einhaltung von Regeln die handgewobenen Stoffe zu einer für die Praxis vernachlässigbaren Streuung der Absorptionswerte führen.
Kontakt: Kurt Eggenschwiler
Finanzierung: Innovationsscheck
Wirtschaftspartner: byvons.swiss
Laufzeit: 2019 - 2020

Validation of the aircraft noise simulation model sonAIR
Validation of the aircraft noise simulation model sonAIR based on measurement data, which was not used in the model development. To that purpose also measurement data from external partners will be used. In addition some open issues of the initial project phase will be studied in more detail.  
Contact: Jean Marc Wunderli
Partner: Swiss International Airlines, DLR, TU Delft
Project funding: FOCA
Duration: 2017 – 2018

Estimation of flight parameters based on radar data
Besides position, orientation and speed, the sonAIR sound source models also needs information on thrust setting and configuration as input parameters. However this information is generally not available. Therefore methods shall be developed on how to estimate aircraft mass, thrust setting and configuration based on radar data. On that basis the range of applications of sonAIR can be substantially extended and will allow to calculate entire airport scenarios in the future.
Contact: Jean Marc Wunderli
Partner: Swiss International Airlines
Project funding: FOCA
Duration: 2017 – 2018

Development and operation of a monitoring system for aircraft noise for the specific demands of sonAIR
In this project a mobile monitoring system together with an automized analysis system shall be developed with the goal of regularly updating the emission database of sonAIR. The monitoring system shall then be used to derive sound source models for recently introduced and modified aircraft types of Swiss International Airlines, such as Bombardier C-Series, Boeing B777 and the modified Airbus A320-family.
Contact: Jean Marc Wunderli
Partner: Swiss International Airlines, skyguide
Project funding: FOCA
Duration: 2017 – 2019

Towards Noise and Weight Reduction by Application of FRP Wheelsets for Freight Wagons
Fiber-reinforced polymer (FRP) composite materials shall be used to manufacture a train wheelset which will generate less noise and leads to a significant weight reduction of the wheelset. The technical feasibility is verified in this project in collaboration with our partners.
Contact: Armin Zemp
Partners: Laboratory for Structural Engineering (Empa), Carbo-Link, PROSE AG
Funding: FOEN
Duration: 2017 – 2018

IDeAL (Impact Driven Assessment of novel Low-noise aircraft concepts) Pilot study
The goal of the IDeAL project is to optimize novel low-noise aircraft concepts and alternative flight procedures with respect to human perception and annoyance.  
The simulation and development of aircraft concepts and flight procedures is done by the German Aerospace Centre (DLR). Its results provide the necessary inputs for auralizations done by Empa. Based on listening tests perceived loudness and annoyance shall be evaluated and used as a feedback-loop to optimize the design. In this pilot study a proof of concept, an identification of open research questions as well as an assessment of the existing optimization potential shall be accomplished.
Contact: Reto Pieren
Project partners: DLR
Project funding: BAFU
Duration: 2017 – 2018
Available Publication

DESTINATE
Under the umbrella of the European Shift2Rail initiative to support research and innovation in rail product solutions, the project DESTINATE aims to develop tools and methodologies for railway noise simulation and cost-benefit analysis of mitigation actions of interior and exterior noise. Empa is involved in the auralisation and visualization of noise mitigation measures with the goal to more accurately predict peoples response to exterior noise from a residents perspective and to interior noise from a passengers perspective.
Contact: Kurt Heutschi
Project partners: Technische Universität Berlin (Coordinator), TUB, Germany, Politechnika Poznańska, PUT, Poland, University of Newcastle upon Tyne, UNEW, UK, Müller-BBM GmbH, MBBM, Germany, Sound Advice in Technology, Innovation and Strategy, SATIS, The Netherlands, Stadler Rail Valencia, STAV, Spain, Netherlands Aerospace Centre, NLR, The Netherlands
Project funding: EU Horizon 2020
Duration: 2016-2018
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Coating of freight wagons for noise mitigation
The goal of this project is to assess the effectiveness of a coating applied to freight wagons for noise mitigation. Besides the sensitivity of the coating material to wear, the impact on the vibratory response of the silo before and after coating as well as the reduction of the noise emission during loading and draining of gravel are experimentally investigated.
Contact: Armin Zemp
Project Partner: Josef Meyer Rail
Project Funding: FOEN
Duration: 2016 - 2017

The Sound of Brass: The Materiality, acoustics and history of brass instruments, based on the example of historically informed replica of German trombones
How were early brass instruments constructed, and of what? If we build copies using historic manufacturing techniques, what impact does this have on their playing characteristics and their sound? And can we measure this?
Many questions on the materiality and the production technology of historical brass instruments remain unanswered today. This project is intended to use reconstructions of the legendary German trombones of the 19th and early 20th centuries to reacquire the techniques of historical craftsmen. The acousticians of Empa are investigating their influence on the playing characteristics and on the radiated sound. The reconstructions of German orchestral trombones built in the course of this applied research will ultimately be presented in concert.
Contact: Armin Zemp
Project Funding: CTI
Duration: 2015–2018

OST
The goal of the project OST is the development of tool to simulate railway rolling noise. The different steps from the excitation mechanisms to vibration propagation to sound radiation and propagation shall be modelled as close to physics as possible. The tool shall be used in a later step to develop acoustically optimized track constructions. The project is financed by FOEN and FOT and is conducted in collaboration with the technical universities of Berlin and Munich.
Contact: Jean Marc Wunderli
Project partner: TU Berlin, TU München
Project funding: BAV, FOEN
Duration: 2015 - 2017

Listening tests to assess the annoyance of helicopter noise compared to wing-mounted propeller driven aircraft
Listening tests are performed in the lab to determine the annoyance rating of helicopters and wing-mounted propeller driven aircraft in different procedures (take-off, landing, cruise). On this basis a source-specific level correction relative to the A-weighted sound exposure level (LAE) shall be deduced for small aircraft.
Contact: Beat Schäffer
Project funding: FOEN
Duration: 2016 - 2017

SiRENE

Participation in the interdisciplinary project SiRENE (Short and Long Term Effects of Traffic Noise Exposure), which investigates acute, short- and long-term effects of road, railway and aircraft noise exposure on annoyance, sleep disturbances and cardiometabolic risk. SiRENE is funded by SNF-Sinergia and is supported by the Federal Noise Abatement Commission EKLB as well as the Federal Office for the Environment FOEN.
Contact: Jean Marc Wunderli
Project partner: Uni Basel, Swiss TPH, n-Sphere, FOEN
Project funding: SNF, FOEN
Duration: 2013 - 2016

SIAS
In the SiRENE project a nationwide assessment of road, railway and aircraft noise exposure was conducted and a socio-acoustic study with 5600 participants was performed. SIAS is a follow-up study in which interviews with about 100 participants of the SiRENE study are carried out at their homes to elucidate – among others – the role of open windows for the well-being of the inhabitants. On that occasion on the one hand short-term measurements are performed to determine the inside-outside level difference for different window positions (closed, tilted, open). On the other hand sound-level meters are flush mounted on the outer face of the closed window to record A-weighted equivalent sound pressure levels in a temporal resolution of 1 s during one week. The first measurements are used to establish a model for inside-outside level differences, the second to validate the exposure modelling of SiRENE.
Contact: Jean Marc Wunderli
Project partner: Swiss Tropical and Public Health Institute, Basel; n-Sphere, Zürich.Project funding: FOEN
Duration: 2016 - 2017

Neue Untersuchungen zum Messverfahren zur Simulation haustechnischer Benutzungsgeräusche mit dem Pendelfallhammer gemäss Schweizer Norm SIA 181 „Schallschutz im Hochbau"
Mit der Neufassung der Schweizer Norm SIA 181 „Schallschutz im Hochbau“ im Jahr 2006 wurde ein Messverfahren zur Simulation von Benutzergeräuschen bei Badewannen, Duschwannen, Waschbecken etc. mit einem Pendelfallhammer eingeführt. Trotz den nicht bezweifelten Vorteilen der Messmethode tauchten in den letzten Jahren vermehrt Fragen zu verschiedenen Problemstellungen auf. Die Eigen-schaften des Pendelfallhammers sind in der Norm nur unzureichend spezifiziert und es mangelt an ei-nem Verfahren, um diese periodisch zu überprüfen. Das Messverfahren ist zu wenig detailliert be-schrieben, so dass sich z.B. je nach Wahl der Anregungspunkte unter Umständen sehr unterschiedliche Resultate ergeben können. Es werden auch keine Angaben zur Messunsicherheit gemacht. Die Norm gibt  für verschiedene Anregungssituationen Korrekturpegel zur Berücksichtigung der Unterschiede zwischen dem Pegel der Originalgeräusche und dem mit dem Pendelfallhammer erzeugten. Diese Kor-rekturwerte werden zum Teil in Frage gestellt. Zudem wird behauptet, dass der durch Schallabstrahlung vom untersuchten Bauteil übertragene Luftschallanteil, je nach baulicher Situation, zu hoch sei und das Messergebnis verfälschen kann. Im Projekt werden die Fragen geklärt und ein Input zur Revision der Norm SIA 181 geleistet.

Ansprechpartner: Kurt Eggenschwiler
Projektförderung: suissetec, BAFU
Projektdauer: 2017-2018

Annoyance caused by wind turbine compared to road traffic noise
On behalf of FOEN listening tests are performed in collaboration with the Catholic University of Eichstätt-Ingolstadt (D) in which participants rate the annoyance caused by different acoustic situations of wind turbine and road traffic noise. With these tests, the (increased) noise annoyance caused by wind turbine compared to road traffic noise can be investigated and quantified. In addition, in a separate experiment special acoustic characteristics of wind turbines are investigated which can influence noise annoyance (e.g., amplitude modulation).

Contact: Beat Schäffer
Project funding: FOEN
Duration: 2014 - 2016

Ecovehicle
In the frame of the Eureka project Ecovehicle, methods to identify and promote environmentally friendly road and rail vehicles are developed together with foreign partners. The work of the Swiss project team: Empa labs Road Engineering / Sealing Components, Automotive Powertrain Technologies and Acoustics / Noise Control and Quantis is funded by Bafu, ASTRA and ARE.
Contact: Kurt Heutschi
Project partner: Empa, Road Engineering / Sealing Components Laboratory, Empa, Automotive Powertrain Technologies, Sciotech Projects, UK, TDC Systems, UK, SVUM, CZ, Kistler, CH
Project funding: FOEN
Duration: 2014 - 2017

sonRoad+
On behalf of Bafu the existing road traffic noise emission model is updated. The model will fit to the properties of the new vehicle fleet and will allow for investigating in greater detail parameters that influence noise emission.
Contact: Kurt Heutschi
Project funding: FOEN
Duration: 2015 - 2017

sonAIR
Within the framework of the sonAIR project we are developing a new calculation model with which low-noise landing and take-off procedures can be computationally validated and acoustically optimized.
Contact: Jean Marc Wunderli
Project partner: n-Sphere, BeSB, SciTracks
Project funding: FOCA, FOEN, Canton of Zurich, airports Zurich and Geneva, skyguide
Duration: 2013 - 2016

sonARMS
Development and maintenance of the shooting noise model sonARMS.
Contact: Jean Marc Wunderli
Project funding: FOEN, Canton of Zurich, Canton of Graubünden
Duration: 2012 - 2016

SONORUS
In the Marie-Curie project SONORUS early stage researchers are educated as “Urban Sound Planers”. In the context of this project a tool to auralise aircraft noise will be developed.
Contact: Kurt Heutschi
Project partner: Chalmers Tekniska Högskola, Chalmers, Sweden, Eindhoven University of Technology, TUe, The Netherlands, Seconda Università degli Studi di Napoli, SUN, Italy, The University of Sheffield, USFD, UK, Ghent University, UGENT, Belgium, Müller-BBM, MBBM, Germany, The Italian National Institute for Environmental Protection and Research, ISPRA, Italy, SP Technical Research Institute of Sweden
Project funding: EU Marie Curie
Duration: 2012 - 2016

VoiceTime
Automatic speaker recognition systems identify humans by their voice.
Contact: Ulrike Glavitsch
Project funding: Gebert Rüf Stiftung
Duration: 2014 - 2016

Shockwave propagation in urban environments
On behalf of armasuisse a model is developed to numerically simulate and predict explosions and the subsequent nonlinear shockwave propagation in urban environments. The simulations will form a basis to determine safety distances.
Contact: Kurt Heutschi
Project funding: armasuisse
Duration: 2014 - 2016

TAURA
Traffic Noise Auralisator: Within the research project TAURA, a traffic noise auralisator will be developed that covers road traffic and railway noise. The key element is a synthesizer that simulates the acoustical emission of a great many of different vehicles, operating on a wide variety of surfaces and under different operating conditions. To obtain the corresponding steering parameters, a hierarchic synthesizer structure with core parameters and global parameters is proposed. Together with the simulation of sound propagation phenomena and a multi-channel reproduction system, complex traffic noise scenarios can be artificially generated and ultimately listened at.
Contact: Reto Pieren
Project funding: SNF
Duration: 2014 - 2016

PhD Thesis  “Direct and Flanking Transmission in Combined Heavyweight and Lightweight Structures“
The aim of this work is to significantly extend calculation techniques for determining sound transmission in wooden structures. This will allow the accuracy of predictions to be significantly increased in comparison to the current, unsatisfactory methods.
PhD Student: Claire Churchill
Supervisor: Prof. Carl Hopkins, Acoustics Research Unit, University of Liverpool

A new method of measuring walking noise on floors
To date in order to evaluate walking noise on a laminated floor the sound of a lady walking on it was directly measured. The aim of the project was to develop a measurement technique which did not require the use of a human subject and also avoided the disadvantage of the ISO tapping machine. A suitable method has been developed and this is been validated by means of a survey. Finally a novel impacting device has been developed which operates very quietly.

Study on the effects of church bells on sleep quality (together with ETH Zurich):
Brink, M., S. Omlin, C. Müller, R. Pieren, and M. Basner, 2011. An event-related analysis of awakening reactions due to nocturnal church bell noise. Science of the Total Environment 409, 5210-5220.

Shooting noise study to establish a scientific basis for Annex 9 of the Noise Abatement Ordinance (together with ETH Zurich)
Brink, M. and J.M. Wunderli, 2010. A field study of the exposure-annoyance relationship of military shooting noise. Journal of the Acoustical Society of America 127, 2301-2311.