Browse Topic: Noise

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Machine Learning-Based Prediction of Wind-Induced Interior Noise in Ground Vehicles2026-01-0599To be published on 04/07/2026
In response to increasing customer demand for enhanced passenger comfort and perceived vehicle quality, OEMs in automotive and commercial vehicles are placing significant emphasis on reducing the interior cabin noise. At highway speeds, wind noise is a primary contributor to the overall noise within the vehicle cabin. Conventional approaches to predict vehicle wind noise rely on physical testing, which can only be conducted in the later stages of the design process once a physical prototype is available. Increased adoption of established computational fluid dynamics (CFD) methods has enabled earlier assessment. However, such simulations require several hours to complete, posing a challenge in the context of rapid design iteration cycles. With the growing adoption of artificial intelligence in engineering, machine learning (ML) approaches have been proposed to predict a vehicle’s aerodynamics performance. Nevertheless, development of ML techniques in the context of aeroacoustics
Higgins, John, Fougere, Nicolas, Sondak, David, Senthooran, Sivapalan, Moron, Philippe, Jantzen, Andreas, Bi, Jing, Oancea, Victor
Simulation-based prediction and optimization of acoustic comfort in vehicle interiors2026-01-0502To be published on 04/07/2026
Passenger expectations for quiet and acoustically comfortable vehicle interiors have increased significantly, driven by advancements in electric vehicles and premium audio systems. Acoustic comfort affects perceived quality, communication ease, and overall driving experience. This paper presents a simulation-driven methodology to predict and optimize interior noise performance during the early design phase, focusing on high-frequency acoustic transfer functions and trim material absorption properties. Traditional NVH development relies heavily on physical testing, which is time-consuming and costly. Early-stage predictive tools are essential to evaluate acoustic performance before prototype availability. High-frequency noise (1kHz–12kHz) is particularly challenging due to complex reflections and absorption behavior. Acoustic trims play a critical role in shaping the cabin’s sound field, and their properties must be optimized to achieve desired sound quality. A novel simulation approach
Baladhandapani, Dhanasekar, Jadhav, Vishal, Du, Isaac
Predicting Electric Vehicle Interior Noise Quality from Drive Unit End-of-Line Vibration Testing2026-01-0223To be published on 04/07/2026
The Noise, Vibration, and Harshness (NVH) quality of electric vehicles (EVs) is heavily influenced by the performance of the electric drive unit. As a critical step in production, End-of-Line (EOL) testing of drive units is used to assess and control component-level NVH before vehicle assembly. However, the correlation between EOL test results and final vehicle interior noise quality, which directly impacts customer satisfaction, is not always fully understood. This paper presents a methodology for characterizing and predicting vehicle interior noise quality based on data from drive unit EOL vibration testing. Our study investigates the intricate relationship between drive unit assembly variations, component tolerances, and the resulting vibrational response. We establish a robust correlation between these drive unit characteristics and both objective vehicle interior noise levels and subjective customer perception. The findings provide a framework for using EOL data to proactively
Arvanitis, Anastasios, Jangid, Kuldeep
A System-Level Calibration Framework for Embedded Vision: Integration of Sensor, Firmware, and Software Enhancements2026-01-0013To be published on 04/07/2026
Embedded vision systems are essential for contemporary applications, including robotics, advanced driver assistance systems (ADAS), and intelligent surveillance; yet they frequently experience diminished image quality due to resource constraints, environmental variability, and inconsistent illumination conditions. Such degradations impact multiple visual attributes-sharpness, contrast, color accuracy, noise levels, and structural similarity-that are critical for reliable perception in safety- and performance-driven domains. This study introduces a comprehensive system-level calibration architecture that integrates three coordinated layers: sensor-level adjustment, firmware optimization, and adaptive software enhancements. At the sensor level, exposure control, gain tuning, and white balance adjustments mitigate luminance imbalance and color shifts under changing light conditions. Firmware optimization leverages image signal processor (ISP) parameters to reduce temporal and spatial
Indrakanti, Rama Kiran Kumar, Vishnoi, Nitin, KAMADI, VENKATA
Self-Supervised Gaussian-Based Framework for Robust Static-Dynamic Decomposition and Real-Time Urban Scene Reconstruction2026-01-0010To be published on 04/07/2026
We propose a self-supervised Gaussian-based framework that enhances the robustness and efficiency of static-dynamic decomposition and high-fidelity reconstruction in autonomous driving scenarios. Existing approaches demonstrate promising performance but remain prone to noisy motion segmentation, overfitting on sparse LiDAR observations, and degraded accuracy in low-texture or distant regions, resulting in unstable geometry. To address these challenges, our method introduces a feature fusion module that jointly exploits image semantics and geometric cues, enabling more reliable motion prior extraction under noise and illumination variations. A cross-sequence geometric consistency constraint is further designed to regularize reconstruction across temporal and viewpoint changes, ensuring physically coherent scene representations. In addition, we formulate an efficient Gaussian parameter optimization strategy that constrains scale and normal updates, preventing unrealistic ellipsoid growth
Feng, Runlei, Wang, Ning, Zhang, Zhihao
Swept Collector Design for the Honda Automotive Laboratories of Ohio Wind Tunnel2026-01-0608To be published on 04/07/2026
Modern aeroacoustic wind tunnels are required to have flat axial static pressure distribution, very low background noise levels, and minimal low frequency pressure fluctuations. These characteristics enable accurate measurement of aerodynamic forces acting on a vehicle as well as identification of noise sources. The collector of an open-jet or ¾ open jet wind tunnel plays a critical role in achieving these goals. Collector self-generated noise contributes to the overall background noise level in the test section, and this contribution has become more significant as other noise sources, such as the main fan, have been addressed through improvements to acoustic treatment. Ever-increasing attention to detail is required to manage noise signatures as the overall facility noise floor is lowered. Furthermore, aspects of collector design that may be beneficial to aerodynamics or pressure fluctuation tend to be some of the worst offenders for noise generation. A new collector configuration was
Best, Scott, Nagle, Paul
Elucidation of Flow Mechanisms Modulating Vehicle Wind Noise by using Large-Scale CFD Simulation2026-01-0614To be published on 04/07/2026
In vehicle development, noise reduction is critical for ensuring passenger comfort. As electric vehicles become prevalent and engine noise is minimized, wind noise becomes more noticeable. Modulated wind noise, which causes a sense of fluctuation due to atmospheric turbulence, wind gusts, and preceding vehicle wakes, causes significant discomfort. This noise is characterized as a high-frequency sound above 1 kHz, modulated at low frequencies owing to the wind velocity and direction fluctuating at several Hz. However, the mechanisms behind wind noise modulation are not fully understood, and no established countermeasures have been developed. This is because wind noise perceived through the side window is primarily caused by the A-pillar vortex and door mirror wake, which coexist as complex turbulent flows around the vehicle. Therefore, identifying the source of modulated wind noise around vehicles under fluctuating wind conditions is difficult. This study aims to identify the source of
Tajima, Atsushi, Hirata, Takumi, Ikeda, Jun, Kamiwaki, Takahiro, Wakamatsu, Junichi, Tsubokura, Makoto
Enhancing LiDAR Performance under Fog with Adaptive Multi-Echo and Feature-Based Filtering2026-01-0011To be published on 04/07/2026
LiDAR (Light Detection and Ranging) systems are essential for autonomous driving (AD) and advanced driver-assistance systems (ADAS), providing accurate 3D perception of the surrounding environment. However, their performance significantly deteriorates under adverse weather conditions such as fog, where laser pulses are scattered by airborne particles, resulting in substantial noise and reduced ranging accuracy. This scattering effect makes it difficult to detect objects within or behind particulate matter, posing a serious challenge for reliable perception in real-world driving scenarios. To address this issue, we propose an algorithm that combines adaptive multi-echo signal processing with a feature-integrated, rule-based denoising framework to enhance LiDAR performance in noisy environments. The multi-echo approach selectively utilizes meaningful signal returns by evaluating both reflection intensity and relative echo positions. Based on predefined rules, the algorithm identifies the
Kaito, Seiya, Zheng, Shengchao, Fujioka, Ibuki, Beppu, Taro
Acoustic simulation for a vehicle audio system across the full audible frequency2026-01-0226To be published on 04/07/2026
Audio system is an important part of vehicle cabin for various purposes. In vehicle development process, it need be tuned for optimal acoustic performance. Traditionally, this process is performed physically on vehicles. In this paper, a methodology is developed to simulate the acoustic performance of the audio system across the full audible frequency range. To quantify the effectiveness, the p/v acoustic transfer functions of the sound pressures at passengers’ ears over the voltage inputs are measured for 12 different speakers in a production vehicle. As the sound perceived by the passengers depends on both the source and the path, the effort of the numerical study mainly concentrates on two aspects: characterization of the loudspeaker parameters and representation of cabin environment. The speaker parameters are characterized from the sound radiation data measured in 2pi chamber. To represent the vehicle cabin, pure finite element model is applied under 1k Hz while a hybrid FE-SEA is
Yang, Wenlong, Patra, Suresh, Hawes, David, Shorter, Phil
CFD-Based Investigation of Fuel Tank Sloshing: Crash Safety and Noise Concerns2026-01-0490To be published on 04/07/2026
A computational study using the Volume of Fluid (VOF) method in SimericsMP+ was conducted to investigate fuel sloshing in automotive fuel tanks under both crash and sudden stop conditions. The SEALs method was employed to rapidly generate the fuel tank mesh, enabling efficient simulation setup. At the outset, a benchmark sloshing case was simulated and compared against experimental data, showing excellent agreement to validate the simulation method. This simulation method was then applied to the fuel tank sloshing scenarios mimicking crash and sudden stop conditions. The study initially focused on a crash scenario where fuel waves impact valves, pumps, and other internal structures. Capturing these localized impact forces is critical for evaluating the risk of component failure and potential leakage. A baffle-equipped tank was simulated and compared with sensor data. Results show that the computed shock forces on valves and baffles closely matched the measurements, demonstrating the
Jia, Kun, Rahman, Ashique
Dog Clutch actuator Control to mitigate NVH2026-01-0003To be published on 04/07/2026
Dog clutches have long been employed in the automotive industry across various applications, including transmission systems, transfer cases, axle disconnects, and hybrid driveline architectures. Their ability to provide direct mechanical engagement makes them ideal for torque transmission with minimal energy loss. However, the transition between engaged and disengaged states can introduce noise, vibration, and harshness (NVH), which may be perceptible to vehicle occupants and affect overall driving comfort. A typical dog clutch relies on interlocking teeth for torque transfer, and its actuation can result in NVH due to factors such as friction between mating surfaces, backlash between engagement components, teeth-on-teeth contact during synchronization, and impact forces during clutch engagement. This paper presents Stellantis’s approach to controlling the actuator system to mitigate NVH effects during clutch engagement and disengagement, focusing on strategies that enhance drivability
Xu, Chengyi, Sagi, Rama Rohit Varma, Madireddy, Krishna Chaitanya, Verhun, Brandon
Optimized Design, Analysis, and Validation of a Tractor Muffler for Enhanced Back-Pressure Control and Cost Efficiency2026-28-0004To be published on 02/12/2026
Internal combustion engines generate intense acoustic pulses during combustion, necessitating the use of exhaust mufflers to suppress noise emissions. With evolving regulations on permissible noise levels and the automotive industry's drive toward lightweight, high-performance vehicles, muffler designs must balance effective sound attenuation, minimal back pressure, and reduced mass. This study presents a comparative analysis of three muffler configurations serpentine, rectangular, and zigzag designed using Solid Works for a light commercial vehicle (LCV) diesel engine. The models were evaluated using computational fluid dynamics (CFD) simulations to assess their acoustic and flow performance. Each design incorporated internal baffle arrangements to enhance sound absorption while aiming to minimize back pressure. The serpentine model featured a perforated baffle layout that promoted multiple reflections and dissipated acoustic energy more efficiently. Simulation results indicated that
Deepan Kumar, Sadhasivam, Palaniselvam, Senthil Kumar, D, Ashokkumar, R, Krishnamoorthy, Mahendran, M, Pasupuleti, Thejasree, G, Dhayanithi, L, Boopalan
An Integrated Model Approach for Predicting Vehicle Dynamics Performance in HiL Validation2026-28-0044To be published on 02/12/2026
In the automotive industry, increasing noise regulations are influencing product sales and passenger comfort, creating a need for more effective noise testing methods. Hardware-in-Loop (HiL) based virtual acoustic testing serves as a critical step before Driver-in-Loop testing, allowing for the assessment of vehicle performance and noise levels inside and outside the vehicle under various conditions before physical prototype testing is performed. The Hardware-in-the-Loop (HiL) simulator setup is equipped with joystick control that requires a physical representation of the vehicle dynamics model provided as a Functional Mock-up Unit (FMU) in real-time format. In contrast, the vehicle control logic is implemented in C++ code. The simulator incorporates both lateral and longitudinal dynamics. Additional interfaces are integrated to support joystick input and virtual road visualization enabling realistic vehicle maneuvering and dynamic performance evaluation. However, performing all test
Visuvamithiran, Rishikesan, Chougule, Sourabh, Srinivasan, Rangarajan, Laurent, Nicolas
New Generation Natural Rubber-Based Bump Stopper with Improved NVH Characteristics2026-26-02921/16/2026
In automotive suspension systems, components like bump stoppers and jounce bumpers play critical roles in controlling suspension travel and enhancing ride comfort. Material selection for these components is driven by functional demands and performance criteria. Traditionally, Natural rubber (NR) has traditionally been favored for bump stopper applications due to its excellent vibration absorption, tear resistance, cost-effectiveness, and biodegradability. However, in more demanding environments, it has been largely replaced by microcellular polyurethane (PU) elastomers, which offer superior durability, environmental resistance, and enhanced noise, vibration, and harshness (NVH) performance. This study revisits NR with the goal of re-establishing its viability by enhancing its performance to match or surpass that of PU. Through compound optimization and advanced material processing techniques, significant improvements have been achieved in NR’s mechanical strength, compression set
Murugesan, Annarajan, Hingalaje, Abhijeet, Perumal, Mathavan, Pawar, Rohit
Comprehensive Evaluation and Development of a Single Cylinder Engine Vehicle for Refinement of NVH Characteristics2026-26-03081/16/2026
The scale of worldwide population presents its own set of difficulties, especially in densely populated cities. Almost every individual has some form of personal transport, which leads to congestion and limited parking space. Automotive manufacturers are scaling down the size of vehicles to resolve these issues to some extent. This paper is based on the NVH development of a single cylinder diesel engine vehicle. It provides an insight into the comprehensive vehicle level NVH refinement approaches adopted. The NVH characteristics of benchmark two-cylinder diesel and baseline vehicle were measured and analyzed for target setting. The performance of each subsystem such as engine mounting, vehicle structure, intake and exhaust was evaluated, and gap analysis was performed against set targets. It was found that the engine mounting system and vehicle structure were inefficient in isolating the excitation forces. The design and location of the mounting system was evaluated using CAE and
Ghale, Guruprasad Chandrashekhar, Baviskar, Shreyas, Bendre, Parag, Kamble, Pranit, Bhangare, Amit, THAKUR, SUNIL, Kunde, Sagar, Wagh, Sachin
Low Idle Boom Noise Reduction on Light Weight Agricultural Cabin Tractor2026-26-01001/16/2026
In last two decades, Farm customer expectation on cabin comfort has been increased multifold. To provide the best-in-class customer experience in terms of comfort without adding cost and weight is bigger challenge for all NVH Engineers. It is evident from literature survey that cabin tractors with better comfort is well accepted by customers in US and European Market. Apart from engine excitation, customer has become more sensitive to customer-actuated-accessory noises due to overall reduction in cabin noise in last 2 decades. This paper presents the study conducted on HVAC blower noise in 30HP cabin tractor. Tactile vibrations and cabin noise is not acceptable when AC is switched on due to low frequency modulating nature in frequency range of ~65Hz and 130Hz. The investigation is carried out systematically considering each component of Source-Path-Receiver model. HVAC blower unit as source is diagnosed in detail to understand root cause. Strong dominance of first order of blower been
K, Somasundaram, Chavan, Amit
Powertrain Radiated Noise Segregation for Internal Combustion Engines2026-26-03521/16/2026
Powertrain is the most prominent source of Noise and Vibration in the vehicle. Improvement in Powertrain Noise and Vibration is a multifaceted topic due to the complex architecture of the powertrain and the critical role of calibration in defining combustion inputs. Hence, a method to clearly distinguish these aspects is required in order to address the exact problem and decide on course of actions to improve NVH performance of powertrains. This paper discusses a post-processing technique through which experimentally acquired ICE Powertrain Noise can be further segregated in order to identify and address the root source. The segregation methodology requires as input - noise, vibration and cylinder pressure values at various torque conditions across multiple operating points. A MATLAB based code developed by the authors is used to generate correlation between the Cylinder Pressure, Torque and Noise Parameters. The transfer coefficient at every frequency point is calculated using
K J, Kishor, Kulkarni, Shriram, Rawat, Udeshya, Pisal, Sangram, Naidu, Sudhakara
Structural and Micro-Geometry Optimization of an Electric Drive Unit for Whine Noise Reduction2026-26-03151/16/2026
The noise generated by pure electric vehicles (EVs) has become a significant area of research, particularly due to the increasing adoption of electrified propulsion systems aimed at meeting OEM fleet CO₂ reduction targets. Unlike internal combustion engines, which mask many drivetrain noises, EVs expose new challenges due to the quieter operation of electric motors. In this context, the transmission system and gear structures have emerged as primary contributors to noise, vibration, and harshness (NVH) in EVs. The present study provides an NVH study that focuses on the gear whine noise issue that is seen at the vehicle level and cascades to the powertrain level. Comprehensive root cause identification, focusing on the transmission system's structural and dynamic behavior. The research emphasizes modifications to both the gearbox housing and gear structures to reduce noise level, and model validation was all part of the study, which was accompanied by physical test results. Using MBS
Baviskar, Shreyas, Kamble, Pranit, Ghale, Guruprasad, Bendre, Parag, Prabhakar, Shantanu, Kunde, Sagar, Thakur, Sunil, Wagh, Sachin
Analysis of Door Seal Compression and its Influence on NVH Performance in Heavy-Duty Vehicle2026-26-03391/16/2026
This study focuses on the effect of door seal compression prediction and its impact on structure borne NVH in trucks. Customer perception of vibrations are envisaged as quality criteria. It is necessary to determine the contribution of seal stiffness due to seal compression under closed condition of the door rather than considering stiffness of the door seal under uncompressed conditions. The dynamic stiffness of door seal is determined from analysis of non-linear type. The simulations are built using the Mooney - Rivlin model. The parameters influencing the compression of door seals in both two – dimension and three – dimension, are identified from the analysis. This involves contemplating the appropriate seal mounted boundary condition on the body and the door of the vehicle. The stiffness after compression of seal is extracted from this non-linear analysis which is further used to obtain the vibration modes for the doors in the truck cabin. As a part of next step, the compressed
L, Kavya, Ramanathan, Vijay
A Strategic Approach to Design Automotive Intake Systems for Achieving a Sporty Acoustic Signature at the Drivers Ear Level2026-26-03281/16/2026
In pursuit of a distinct sporty interior sound character, the present study explores an innovative strategy for designing intake systems in passenger vehicles. While most existing literature primarily emphasizes exhaust system tuning for enhancing vehicle sound quality, the current work shifts the focus toward the intake system’s critical role in shaping the perceived acoustic signature within the vehicle cabin. In this research work, target cascading and settings were derived through a combination of benchmark and structured subjective evaluation study and aligning with literature review. Quantitative targets for intake orifice noise was defined to achieve the desired sporty character inside cabin. Intake orifice targets were engineered based on signature and sound quality parameter required at cabin. Systems were designed by using advanced NVH techniques, Specific identified acoustic orders were enhanced in the intake system to reinforce the required signature in acceleration as well
Sadekar, Umesh Audumbar, Titave, Uttam, Patil, Jitendra, Naidu, Sudhakara
Dual-Stage Compressor Bracket NVH Optimization for High-Performance 4×4 Electric Vehicles2026-26-03271/16/2026
The rising demand for high-performance 4x4 electric vehicles (EVs) has necessitated development in Noise, vibration and harshness (NVH) optimization, especially in critical components such as compressor bracket. This study focuses on NVH optimization of a dual-stage compressor bracket, comparing its performance against conventional single stage isolation bracket. The dual-stage bracket is evaluated for isolation effectiveness, modal frequency alignment, and overall NVH performance, while ensuring compliance with stiffness targets. Additionally, dual-stage design meets stringent stiffness requirement, confirming structural integrity under dynamic loads. Modal analysis results reveal that the dual-stage configuration effectively shifts critical frequencies away from operational ranges, reducing resonance risks. The results highlight the dual-stage bracket's ability to address NVH challenges in high-performance 4x4 EVs, offering a robust solution for improving cabin comfort and vehicle
Hazra, Sandip, Tangadpalliwar, Sonali
NVH Refinement on the Agriculture Tractor using Coupled Test and Simulation Approach2026-26-03161/16/2026
The Indian farmers choice of agriculture tractor brand is driven by the ease of operation and fuel efficiency. However, the customer preference for operator comfort is driving many tractor OEMs for improvement in noise and vibration at the operator location. Also, the compliance to CMVR regulation for noise at operator ear location and vibration at operator touch point location are mandatory for all the tractors in India. NVH refinement development of the tractor plays a critical role in achieving the regulated noise level and improved tactile vibration In presented work, the airborne sources such as exhaust tail pipe, intake snorkel and cooling fan are quantified by at tractor level through elimination method. The detailed engine level testing in engine noise test cell (hemi anechoic chamber) is carried out to estimate the contribution of engine components to overall noise. The outcome of Noise source identification (NSI) has revealed silencer, timing gear cover and oil sump to be
Gaikwad, Atul Annasaheb, Harishchandra Walke, Nagesh, Yadav, Prasad S, Bankar, Harshal
An Analysis of Material Damping Characteristics: A Comparison of Oberst Bar Method and Center Impedance Method and their Relationship to Component Level for EV Application2026-26-03171/16/2026
Damping materials exhibit advantageous mechanical and acoustic characteristics that enhance the structural integrity of systems. These materials find extensive applications across various industries, including automotive, aerospace, and building acoustics, and are widely employed in the development of soundproofing materials. The damping characteristics of materials primarily pertain to the dissipation of vibrational energy, the reduction of oscillations, and the controlling and subsequent attenuation of vibration-induced noise emanating from structures. To improve both structural integrity and acoustic performance, it is crucial to accurately assess the damping properties of these materials. The Oberst bar test method is a standard method used in the automotive, railway and building industry for initial optimization of damping material However, questions have arisen about the degree to which the outcomes of the Oberst test truly reflect real-world applications. Numerous experimental
Kamble, Prashant Prakash, Joshi, Manasi, Jain, Sachinkumar, Harishchandra Walke, Nagesh
Simulation Based Optimization of the NVH Characteristics in Modern High Speed Engine During Development Phase2026-26-03261/16/2026
Engine noise mitigation is paramount in powertrain development for enhanced performance and occupant comfort. Identifying NVH problems at the prototype stage leads to costly and time-consuming redesigns and modifications, potentially delaying the product launch. NVH simulations facilitate identification of noise and vibration sources, informing design modifications prior to physical prototyping. Early detection and resolution of NVH problems through simulation can significantly shorten the overall development cycle and multiple physical prototypes and costly redesigns. During NVH simulations, predicting and optimizing valvetrain and timing drive noise necessitates transfer of bearing, valve spring, and contact forces to NVH simulation models. Traditional simulations, involved continuous force data export and NVH model evaluation for each design variant, pose efficiency challenges. In this paper, an approach for preliminary assessment of dB level reductions across design iterations is
Rai, Ankur, Deshpande, Ajay Mahadeo, Yadav, Rakesh
Noise Reduction of Construction Equipment Vehicle Through Structure-Borne and Air-Borne Noise Reduction Strategy2026-26-03181/16/2026
One can witness the constant development and redevelopment of cities throughout the world. Construction equipment vehicles (CEVs) are commonly used on the construction site. However, the noise pollution from construction sites due to the use of CEV has become a major problem for many cities. The construction equipment employed is one of the main causes of these elevated noise levels. The construction workers face a potential risk to their auditory health and well-being due to the noise levels they are exposed to. Different countries have imposed exterior and operator’s ear noise limits for construction equipment vehicles, enabling them to control noise pollution. In this study, three vehicles were selected and checked for NVH performance and found that the operator ear noise level of the identified vehicle is 6 dB(A) higher than the benchmark vehicle level in dynamic conditions, when tested as per ISO 6396. Similarly, there was another vehicle having exterior noise 2 dB(A) higher than
Shinde, Gaurav, Jawale, Pradeep, Jain, Sachinkumar, Harishchandra Walke, Nagesh
Sound Quality Refinement and Vibration Reduction During Horn Application in Electric Vehicles2026-26-03381/16/2026
This paper focuses on the cabin sound quality refinement and the tactile vibration reduction during horn application in the electric vehicle. A loud cracking sound inside the cabin and higher accelerator pedal vibration are perceived while operating the horn. Sound diagnosis is carried out to find out the frequencies causing the cracking noise. Transfer path analysis is conducted to identify the nature of noise and the predominant path through which forces transfer. Based on finding from TPA, various recommendations are evaluated which reduced the noise to a certain extent. Operational Deflection Shape (ODS) is conducted on the horn mounting bracket and on the body to identify the component having higher deflection at the identified frequencies. Recommendations like DPDS improvement on the horn bracket and the body is assessed and the effect of each outcome is discussed. With all the recommendations proposed, the cabin noise levels are reduced by ~ 8 dB (A) and the accelerator pedal
S, Nataraja Moorthy, Rao, Manchi, R, Ashwin sathya, S, THARAKESWARULU, Raghavendran, Prasath
Investigation and Reduction of Road Noise due to Transient Road Inputs in Electric Vehicle2026-26-03581/16/2026
Higher road noise is perceived in the cabin when the test vehicle encounters road irregularities like bump or pothole in the public roads. The transfer of transient road inputs inside the body caused objectionable cabin noise. Measurements are conducted at different road surfaces to identify the patch where the objective data well correlated with the noise measured at the public road. Wavelet analysis is carried out to identify the frequency zones since the events are transient in nature. TPA is carried out in time domain to identify the nature of the noise and the dominant path through which the transient road forces are transferring inside the body. Based on the outcome of TPA, various countermeasures like reduction of dynamic stiffness of suspension bushes, TMDs on the path are proposed to reduce the structure borne noise. Criteria which need to be considered for reduction of cabin noise due to transient road inputs is also discussed.
S, Nataraja Moorthy, Rao, Manchi, Selvam, Ebinezer, Raghavendran, Prasath
Optimizing Tire NVH Performance in Electric Vehicles: A Comprehensive Approach Using Benchmarking, Simulation, and Validation2026-26-06051/16/2026
The present study enumerates the effectiveness of using Foam-inside Tyres (FIT) for attenuating the in-cabin noise due to tire-road interaction in Internal Combustion Engines (ICE) converted Electric SUVs (E-SUV). Due to the elimination of the ICE Prime movers in (E-SUV), the Tyre booming, Tyre cavity, and rumbling noise in the structure-borne region are significantly audible in the driver’s & passenger's ears globally for E-SUVs. Foam tyres reduce tyre cavity resonance. However, the effectiveness of the acoustic foam is predominant between 180 to 240 Hz only. In the present study, In Cabin Noise (ICN) measurement was completed on the comfort testing track, and the results of structure-borne in-cabin noise up to 500 Hz were analysed. These measurements identified the vehicle in-cabin sensitive frequencies, which are affected by the tyre and wheel assembly. To analyse the contribution of the Tyre design parameters and to predict the ICN performance in the whole vehicle simulation, CD
Singh, Ram Krishnan, Deivasigamani Purushothaman, Balakrishnan, Paua, Ketan, Ahire, Manoj, Adiga, Ganesh N
Investigation of Low Frequency Interior Noise due to Tyre-Road Interaction2026-26-03511/16/2026
Unlike internal combustion engine (IC Engine) vehicles, the rapidly growing electric vehicle (EV) market demands tyres with superior yet often conflicting performance characteristics. The increased weight of EVs, due to their heavy batteries, necessitates robust tyres with reinforcement and higher inflation pressure. Conversely, increased wear due to higher initial torque and the need for lower rolling resistance to extend range, combined with the requirement for better grip for improved handling, call for advanced compound and tread pattern designs. EV tyres need to be stiffer, lighter, and low hysteresis, making it very hard to reduce low-frequency (20-200 Hz) interior noise that was previously masked by engine noise. This study investigates the low-frequency (20-200 Hz) structural-borne interior noise performance of EV tyres using both experimental and simulation tools. By wisely tuning the tyre's stiffness, mass, and damping properties, the necessary noise targets can be achieved
Subbian, Jaiganesh, M, Saravanan
Developing Advanced CAE Model for Door Glass Regulator Operating Noise Reduction through TEST-CAE Correlation2026-26-03111/16/2026
In recent decades, Computer-Aided Engineering (CAE) has become increasingly critical in the early stages of vehicle development, particularly for performance improvement and weight optimization. At the core of this advancement lies the accuracy of CAE models, which directly impacts design insights and reliable TEST-CAE correlation. Yet, accurately replicating real-world physical systems in virtual environments remains a significant challenge. This research introduces a structured methodology for improving correlation in door system models. It focuses specifically on reducing glass regulator operating noise, a common design issue that can lead to unwanted sounds and passenger discomfort. Traditional CAE models often fail to predict this problem, exposing the limitations of virtual-only validation. To address this gap, the study proposes a modal correlation-based approach aligned with actual assembly stage conditions. This strategy enables more precise assessment of the glass regulator’s
Panuganti, Naresh Kumar, Choi, Seungchan
Use of Statistical Energy Analysis to Predict Articulation Index (AI) in a Vehicle Interior for Real-World Operating Scenarios2026-26-04301/16/2026
Vehicle interior noise is a crucial assessment criterion for automotive NVH. It has a significant effect on customer opinions about the quality of a vehicle. Articulation Index (AI) is one of the key sound metrics used to describe speech intelligibility and quantifies the middle and high frequency spectra associated to the internal noise of vehicle. In reality, Vehicle operating under dynamic condition experiences various air-borne noise sources such as tire rolling noise, powertrain noise, intake-exhaust noise & wind noise along with structure borne excitations such as powertrain vibrations, suspension vibrations. It is very challenging to predict cumulative effect of all these excitations to interior noise level and Articulation Index (AI) of vehicle over complete frequency range. The statistical energy analysis (SEA) is a well-known methodology being used to simulate & predict mid & high frequency noise. Objective of this paper is to present the process of development of a SEA
Doijad, Vishwajit Padmakar, Billade, Dayanand, Apte, Sr., Amol Arun, Shewale, Amol, Kothapalli, Brahmananda Reddy
Electromagnetically Levitated Engine Mount2026-26-03421/16/2026
In the evolving landscape of the automotive industry, enhancing passenger comfort and ride quality has become a key differentiator for manufacturers. While suspension systems have traditionally received significant attention, powertrain isolation through engine mounts plays an equally critical role in controlling noise, vibration, and harshness (NVH). Engine mounts are not only responsible for supporting the powertrain’s weight but also for mitigating the transmission of unbalanced engine forces to the vehicle body. Modern engine mount designs aim to eliminate any metal-to-metal contact between the powertrain and chassis, thereby achieving optimal vibration isolation. This study proposes a refined approach to completely decouple the powertrain from the vehicle structure, ensuring minimal vibration transfer and thereby extending the operational life and performance of the engine mount system.
Hazra, Sandip, Naik, Sarang Pramod, More, Vishwas
Prediction of Trimmed Body Noise Transfer Function Based on BIW Response Using Machine Learning2026-26-06401/16/2026
This work focuses on the prediction of Trimmed Body Noise Transfer Function (NTF) using Glazed BIW (body in white) structural model characteristics by leveraging Machine Learning (ML) technique. Inputs such as Glazed BIW (GBIW) attachment dynamic stiffness, Body Panel Vibration Transfer Functions (VTF) and Driver Ear level NTFs are employed to predict Trimmed Body NTF for a particular hard point. An iterative process of performing design modifications on the BIW to verify its effect on BIW performance and therefore on Trimmed body NTF is undertaken. BIW geometric parameters are varied in an organized manner to generate hundreds of data points at GBIW level which are provided as input to the train the ML model to predict the trimmed body level NTF. The outcome provides crucial insights of how the trimmed body NTF is closely related to the GBIW design characteristics. This ML approach of predicting trimmed body NTF based on GBIW characteristics provides critical insight about GBIW design
Kulkarni, Prasad Ramesh, Bijwe, Vilas, Kulkarni, Shirish, Sahu, Dilip, Inamdar, Pushpak
Development of a GUI-Based Pitch Sequence Optimization Tool for Tire Noise Reduction2026-26-03301/16/2026
Tire noise reduction is important for improving ride comfort, especially in electric vehicle due to lack of engine noise and majority of the noise generated in-cabin is from tire-road interaction. Therefore, the tire tread pattern contribution is one of the important criteria for NVH performance apart from other structurally generated noise and vibration. In this work a GUI-based pitch sequence optimization tool is developed to support tire design engineers in generating acoustically optimized tread sequences. The tool operates in two modes: without constraints, where the pitch sequence is optimized freely to reduce tonal noise levels; and with constraints, where specific design rules are applied to preserve pattern consistency and manufacturability. The key point to be considered in this pitch sequence is that it should be reducing the tonal sound and equally spread i.e., the same pitch cannot be concentrated on one side which may lead to non-uniformity. So, the restriction is that
Sampathraghavan, Lakshmi, Ramarathnam, Krishna Kumar, Mantripragada PhD, Krishna Teja, Ramachandran, Neeraj
Assessment of Low-Frequency Structure-Borne Road Noise for Battery Electric Vehicle: Prediction and Improvement2026-26-03201/16/2026
In the absence of engine noise, road-induced noise has become a major concern specifically for Battery Electric Vehicles (BEVs), impacting Sound Pressure Level (SPL) for both drivers and passengers. Under the influence of random road load inputs, structural vibrations which transfer from road and tire to suspension to vehicle body, the cabin interior noise, particularly at lower frequencies, is significantly affected. To improve the road-induced low-frequency structure-borne noise behaviour, which frequently perceptible as ‘booming noises’, a study was carried out to assess predominant noise sources present in vehicle and to suggest refinements in reducing the noise levels. By considering random excitations of road profile through tire patch using CD-Tire model, vehicle interior noise was computed. Subsequently, to get insight of dynamic behaviour of vehicle, various diagnostic assessments to understand the influence from structure and paths were deployed. Major contributors from body
Paik, Suman, Raghuvanshi, Jayeshkumar, Chaudhari, Vishal Vasantrao, V, Radhika
Failure Investigation and Geometric Optimization of Torsional Vibration Damper for Enhanced Durability and Noise Reduction in Automotive Drivetrain Systems2026-26-03501/16/2026
Internal Combustion engines exhibit multi-order vibrations caused by the inertial forces of reciprocating masses. These vibrations induce drivetrain resonance, negatively impacting occupant comfort and the durability of drivetrain components. Torsional vibrations, a critical subset of these oscillations, demand efficient damping mechanisms. Torsional Vibration Dampers are instrumental in minimizing such vibrations by tuning mass and frequency characteristics to prevent resonance. By splitting resonant frequencies into avoidable zones within the engine's operational range, TVD enhance vehicle performance and refinement by dampening the vibrations. Structurally, TVD comprise an inertia ring integrated with a damping medium, such as vulcanized rubber, which attenuates torsional oscillations by permitting controlled oscillation of the inertia ring. This study focuses on the failure investigation and the geometric optimization of oscillating masses of TVD for performance and durability
Wani, Sujit Ashok, S, Manickaraja, Kanagaraj, Pothiraj, Senthil Raja, T, Vellandi, Vikraman, Patil, Dilip
Development of a Systematic Methodology for Identifying and Mitigating Squeak & Rattle Issues in Automotive Seating Systems2026-26-03331/16/2026
The automotive industry constantly strives to enhance vehicle safety, comfort, and customer satisfaction. One of the critical aspects influencing these factors is the mitigation of Buzz, Squeak, and Rattle (BSR) issues, which can significantly impact perceived vehicle quality and user experience. This paper focuses on the BSR challenges specifically encountered in bench seat latch & striker mechanisms. Vibrations and movement, especially during vehicle operation, exacerbate Buzz, Squeak & Rattle (BSR) problems, leading to acoustic disturbances that detract from the overall ride quality. Latch and striker in seat system is prone to squeaks and rattles (S&R) due to improper fitment, environmental conditions, or mechanical stress. These issues not only compromise the auditory experience but may also raise concerns about component durability and functionality. This paper outlines the root causes of BSR phenomena in these components, emphasizing the role of design optimization, material
Deole, Sameer Shrikant, Rahman, Shafeeq, Mohammed, Riyazuddin, Shah, Prashant
Evaluation of Driveline NVH Performance Using Linear Dynamic Finite Element Simulation2026-26-03221/16/2026
Automotive driveline design plays an important role in defining a vehicle’s Noise, Vibration and Harshness (NVH) characteristics. Driveline system, responsible for torque transfer from the engine/transmission to the wheels, is exposed to a wide spectrum of vibrational excitations. The industry’s shift toward turbocharged engines with fewer cylinders while maintaining the equivalent torque and power has led to increased low-frequency torsional vibrations. This paper presents some key design considerations to drive the NVH design of a driveline system using linear dynamic FE simulations. Using an E-W All-Wheel Drive driveline architecture with independent suspension as a case study, the influence of various subsystem modes on driveline NVH performance is examined. The paper further explores the strategies for vibration isolation, motion control, and mode management to identify the optimal bushing rates and its location. Furthermore, it examines the ideal bushing specifications for
Joshi, Atul Kamalakarrao, Subramanian, MANOJ
A Scientific Approach to Identify the Source of Intermittent Steering Rattle Noise and Implementing the Design Solutions2026-26-03461/16/2026
Body-on-frame vehicles are well-regarded for their durability and off-road capabilities, but their structural design often makes them more vulnerable to noise, vibration, and harshness (NVH) issues. Vibrations originating from uneven roads are transmitted through the suspension and steering assemblies, sometimes resulting in rattles or other disturbances. These vibrations can be amplified by the inherent flexibility in the body-to-frame mounting system. In such vehicles, the steering system plays a critical role in driver comfort and is highly sensitive to vibrational inputs from the road surface, especially on coarse or uneven terrain. Occasionally, these inputs result in subtle rattle noises that are perceptible only to the driver and may not be detected under controlled testing environments. This poses a challenge for engineers trying to isolate and resolve such intermittent NVH phenomena. Identifying the source requires a combination of real-world driving evaluations, structural
Ramesh Chand, Karan Kumar, Gopinathan, Haridoss, Kabdal, Amit
Black Box Approximation of EMI/EMC Filter Parasitic’s2026-26-03681/16/2026
Selecting the right EMI/EMC filter is a major challenge when system noise levels exceed compliance or pre-compliance limits. Inline PCB filters are designed to mitigate noise in standalone conditions, but their behavior changes when integrated into a larger system due to unknown parasitic’s. These parasitic’s can disrupt electromagnetic compatibility (EMC), leading to non-compliance [1, 2]. To address this, engineers often use off-the-shelf EMI filters, but determining their real-world effectiveness remains complex. Even with simulation-based methods, accurately predicting insertion loss and attenuation is difficult due to limitations in conventional modeling approaches [4, 5]. Traditional SPICE-based simulations rely on static models defined at specific frequency points, with interpolated values for intermediate frequencies. This interpolation introduces inaccuracies, affecting the precision of simulated results [6, 8]. To overcome these limitations, we propose a methodology that
Pandey, Devbrat, Unterreiner, Michael, Mishra, Arvind, singh, Ankur
Adaptive Control Algorithms for Active Mounts on Diesel Powertrains in Passenger Cars2026-26-03241/16/2026
Diesel powertrains are inherently characterized by high vibration levels and low-frequency excitations, which are extremely demanding for passenger comfort and vehicle refinement. Conventional passive engine mounts often fall short in mitigating such vibrations effectively across a wide range of operating conditions. Passive mounts are inadequate for effectively isolating vibrations in powerful, lightweight vehicles or those without a balancer shaft 3-cylinder engine ordiesel engines. Consequently, this has prompted the consideration of active engine mounts as an alternative solution for solving NVH (Noise, Vibration, Harshness)-related issues. This paper explores the application of adaptive control algorithms in active engine mount systems for diesel powertrains in passenger vehicles. Through the integration of real-time feedback loops with smart control strategies the system adaptively controls mount stiffness and damping to minimize engine-induced vibrations. The study presents
Hazra, Sandip, Khan, Arkadip Amitava, more, Vishwas
Resolution of Automotive Air Compressor Noise in Low Powered ICE Vehicles2026-26-03141/16/2026
The interior noise and thermal performance of the passenger compartment are critical criteria for ensuring driving comfort [1]. This paper presents the optimization of air conditioning (AC) compressor noise, specifically for the low-powered 1.0 L - ICE engine paired with a 120 cc IVDC compressor. This combination is quite challenging due to the high operational load & higher operating pressure. To enhance better in-cabin cooling efficiency, compressor’s operating efficiency must be improved, which necessitates a higher displacement of the compressor. However, increased displacement results in greater internal forces which leads to more structure-borne induced noise inside the cabin. For this specific configuration, the compressor operating pressure reached up to 25 bars under most driving conditions. During dynamic driving scenario, a metallic tonal noise from the compressor was reported in a compact vehicle segment. It is reported as very annoying to passengers inside. A comprehensive
John Britto, Vijay Antony, Maluganahalli-Dharmappa Madhusoodan Sr, Madhusoodan, Natarajasundaram, Balasubramanian
An Engineering Perspective on Cradle and Saddle Mount Configurations2026-26-03131/16/2026
The evolution of electric vehicles (EVs) also demands the evolution of powertrain mounting systems to achieve superior Noise, Vibration, and Harshness (NVH) performance. This study presents a comparative evaluation of cradle, saddle and ladder mounting systems in EV applications. Examples of experimental modal analysis and vehicle-level vibration tests were performed in order to evaluate structure-borne noise transmission as well as airborne noise transfer under operating conditions. Important parameters like mount stiffness, isolation efficiency and dynamic load distribution were performed. These findings provide valuable guidance for selecting optimal mount strategies to enhance occupant comfort and acoustic quality in future EV designs. Recommendations for mount system improvements considering evolving EV architectures are also discussed. This work provides a crucial, experimentally-validated framework for selecting optimal mounting architectures, addressing a key gap in the
Hazra, Sandip, more, Vishwas, Naik, Sarang Pramod
Contradictions of Automotive NVH and TRIZ Tools for Innovative Problem Solving2026-26-03471/16/2026
Balance towards various Vehicle attributes often faces design contradictions, particularly in Noise, Vibration, and Harshness (NVH) optimization. Traditional approaches rely on trade-offs, but TRIZ (Theory of Inventive Problem Solving) offers a structured methodology to resolve contradictions innovatively. This paper presents TRIZ-based solutions for 2 key NVH challenges: (1) exhaust systems requiring noise reduction while maintaining low engine back-pressure, (2) engine mounts requiring both softness for vibration isolation and hardness for durability & vehicle stability, By applying TRIZ principles such as separation, mechanics change, etc. and using Thinking Tools such as thinking in time & scale, novel solutions are proposed to achieve superior performance without traditional compromises. These case studies demonstrate how TRIZ enhances automotive NVH refinements by enabling systematic innovations. This also explores benefits of Frugal Engineering for profitable launch of new
A, Milind Ambardekar
Transforming Gear Manufacturing: A Deep Learning Approach to Quality Prediction2026-26-06461/16/2026
The automotive industry is rapidly transitioning towards Industry 4.0, transforming vehicle manufacturing. To achieve a lower carbon footprint, it is crucial to minimize raw material wastage and energy consumption. Reducing component wastage, lead time, and automating gear manufacturing are key areas. Gear micro-geometry inspection is vital, as variations affect service life and NVH (Noise, Vibration, Harshness). Despite standards for permissible errors, manual evaluation of gear microgeometry inspection is often needed. This subjective evaluation approach will have a possibility that a gear with undesired variations gets assembled into the product. These issues can be detected during NVH testing, leading to replacement of part and re-assembly thus increasing lead time. This generates a need for an automated system which could reduce the human intervention and perform gear inspection. The research aims to develop a deep learning-based model to eliminate the ambiguity of manual
Ramakrishnan, Gowtham Raj, Baheti, Palash, PR, Vaidyanathan, Durgude, Ranjit, Bathla, Archana, R, Greeshmita, V, Rangarajan
26SIAT-1032-Experimental Frequency-Based Substructuring for Full-Vehicle NVH Characterization in Electric Vehicles2026-26-03091/16/2026
The area of electric vehicles (EV) has fully arrived with almost every OEM enhancing electric vehicles in their portfolio. However, regarding its business potential numerous challenging engineering questions have risen. Especially vehicle NVH development needs to be rethought as masking noise from classical internal combustion engines (ICE) are gone. At the same time the frequency content of electric engines falls in the best human audible range, creating high potential for annoying tonal acoustic issues. With NVH design requirements now pushed up into the kilohertz range, many classic development strategies fail or lack efficiency. VIBES Technology’s answer to this challenge is what we call Hybrid Modular Modelling (HMM). This modelling strategy combines test-based and numerical simulation throughout the vehicle development cycle. Using best of both worlds, HMM allows accurate virtual (part / system) design and optimization on full vehicle level. Here HMM is based on the latest
Kohlhofer, Daniel, Pingle, Pawan Sharad, de Klerk, Dennis
Analysis and Optimization of Noise and Vibrational Performance of an Electric Axle2026-26-03401/16/2026
As the electric mobility landscape evolves, there is a growing emphasis on addressing the Noise, Vibration, and Harshness (NVH) challenges associated with electric drivetrains. The absence of an IC engine in EVs shifts the focus to other noise contributors such as gear meshing, electric machine operation, and structural vibrations. Despite the known influence of micro-geometry on gear dynamics, current optimization practices often rely on empirical adjustments or standard guidelines without fully utilizing advanced computational methods to predict and optimize NVH performance. There exists a pressing need for a systematic approach to analyze and optimize gear micro-geometry to reduce noise and vibration in high-speed e-axle applications. This research aims to bridge that gap by investigating the relationship between micro-geometry optimization and NVH characteristics of an e-axle. Through detailed modelling and optimization techniques, this research aims to identify optimal gear micro
Ankit, Priyadarshi, Kulkarni, Krishna, Momin, Vaseem
Combustion Noise Quality Improvement in a Common rail Diesel Engine at Low Idle using Taguchi DOE2026-26-03291/16/2026
Noise quality at idle condition is an important factor which influences customer comfort. Modern diesel engines with stringent emission norms together with fuel economy requirements pose challenges to noise control. Common rail engine technology has advantage of precise fuel delivery and combustion control which needs optimization to achieve the conflicting requirements of noise, emission and fuel efficiency. Engine noise at low idle condition is dominated by combustion noise which depends on rate of pressure rise inside the cylinder during combustion. The important parameters which influence cylinder pressure rise are fuel injection timing, pilot injection quantity and its separation, rail pressure and EGR valve position. The study on effect of these parameters at varying levels demand large no of experiments. Taguchi design of experiments is a statistical technique which can be used to optimize these parameters by significantly reducing no of experiments needed to achieve the desired
P, Priyadarshan, Chavan, Amit, A, Kannanswamy, Patil, Sandeep, Chaudhari, Vishal V
Tractor Cabin Structure Borne Noise Reduction in the Virtual Environment2026-26-01011/16/2026
In recent days, cabin variants in the tractor are preferred by the farmers for the Coziness and longer field hour operation with less fatigue. Noise perceived by customer is the most important factor taken into account during the design stage, as it’s directly linked with operator’s comfort. Observed noise levels has to be within the defined limits as per national/international standards Overall cabin noise levels is contributed by the structure borne noise below 630 Hz. Structure borne noise is the noise typically radiated by the door, roof, windshield, floor, fender and structure assembly due to the engine excitation through the transmission housings and backstories. This paper depicts the process of tractor cabin structure borne noise prediction in the virtual environment. Firstly, Engine bearing loads and axle bearings has been extracted in the virtual stage from the vehicle level driveline model using commercially available MBD software. The finite element (FE) model of the cabin
Qunasekaran, Pandiyanayagam, K, Somasundaram, Chavan, Amit
Road Noise Improvement of a Passenger Vehicle through End-to-End CAE-Simulation Using Transfer Path Analysis (TPA) Approach2026-26-04311/16/2026
Refined NVH performance of a vehicle is a mark of premium quality. Achieving the desired NVH performance in different vehicle operating conditions is always a Herculean task and early stage “CAE design recommendations” play crucial role in overall vehicle design development. This becomes tougher when the program is very much cost, weight and timeline sensitive. This paper explores simulation approach for addressing a major noise issue for a vehicle running at a constant speed on a rough road. While working on any issue, the first and the most critical step is to identify the exact root cause of the issue. Hence, we propose a detailed full vehicle level “contribution analysis (CA) + transfer path analysis (TPA)” methodology (everything done through the simulation) and then go for the design recommendations to improve the performance. We used road excitation power spectral density (PSD) as the input at all the four wheels (spindle locations) calculated through MBD software. The first
Mahajani, Mihir, Nascimento, Fabio, Adinarayana Reddy, Kodidela, Matyal, Mahantesh, Tenagi, Irappa, Sardar, Chenna
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