Browse Topic: Tests and Testing

Items (23,425)
This specification covers a leaded bronze in the form of sand and centrifugal castings (see 8.6).
AMS D Nonferrous Alloys Committee
This SAE Recommend Practice establishes for passenger cars, light trucks, and multipurpose vehicles with GVW of 4500 kg (10000 pounds) or less, as defined by the EPA, and M1 category vehicles, as defined by the European Commission:
Interior Climate Control Vehicle OEM Committee
 Grade climbing capacity establishes a vehicle's distinguishing attribute of handling uneven roads and terrains thereby enhancing its overall performance capability. Vehicle availability and the testing procedure to determine gradeability requires a lot of time and effort. Aiming for the prediction of maximum start-stop gradeability of a vehicle and reducing the testing time and resources, a methodology is established representing the test procedure. A vehicle model is developed in GT Suite having dedicated modules of engine, clutch, transmission, vehicle and a driver. The vehicle is having weight of 2999 kg and a 1499 cc of engine with 80 hp power and 210 Nm torque. In simulation, the driver targeted the engine's launching speed profile, which progressively engaged the clutch to prevent engine stalling. The target is to ascend a specified distance in a predetermined amount of time without stalling the engine. Upon reaching the maximum grade the vehicle can climb, the engine will not
Ramadandi, PadmavathiBose, AnshumanSirangu, SatishYeldo, JabinEdgar, ShawnSalve, SiddheshKaushik, Prince
The electric vehicle driveline generates less vibration and noise compared to a conventional internal combustion engine vehicle, making it harder for the driver to perceive the vehicle’s operating status through driveline sounds, thereby diminishing driving engagement and experience. To compensate for the absence of engine sound in EV drivelines, Active Sound Design (ASD) technology has become a crucial method for drivetrain sound enhancement, with sound synthesis algorithms playing a key role in this process. Although pitch-shifting algorithms based on frequency shift principles can synthesize engine sounds, they suffer from spectral leakage and stuttering caused by sound splicing. To address these issues, a pitch-shifting synthesis algorithm (QCPS, Quadratic interpolation-based Continuous audio sample indexing Pitch Shifting algorithm) is proposed in this paper, which combines a quadratic interpolation method with a continuous audio sample indexing strategy. First, the frequency
Liu, DezhuXie, LipingLiu, ZhienLu, Chihua
The article introduces the air springs, CDC, rear-wheel steering system, braking system, front-wheel steering system, and electric drive system in the vehicle’s central coordinated motion control system. It explores achieving more comfortable shock absorption by adjusting the CDC (Continuously Variable Damping system) damping and other means. By combining open-loop and closed-loop rear-wheel steering control, the turning radius in small-radius steering mode is reduced by up to 10%, enabling crab-walking, optimizing the moose test entering speed up to 90.9 kph, and improving vehicle behavior on split-friction surfaces. Through the cooperation of IBS (Intelligent Brake System) and VMC, an extremely comfortable braking process is achieved.
Zhou, YuxingLi, Wen
Ammonia-diesel dual-fuel engines can effectively reduce greenhouse gas (GHG) emissions. Aiming at the real-time control requirements of ammonia/diesel dual-fuel engines, this study proposes a segmented real-time modeling method and a heat release rate model simplification strategy by linearized heat release rate curves. First, the engine working cycle is divided into three parts: intake and exhaust stage, compression and expansion stage, and combustion process. Different simulation steps and modeling strategies are designed to optimize computational efficiency while maintaining the necessary level of accuracy at each stage. Secondly, based on the calibrated heat release rate (HRR) curves, feature points are extracted to construct a simplified linear heat release model. In the absence of calibration data, the characteristic points of the HRR curves are obtained through interpolation. Compared with the commonly used combustion model, the Wiebe model, the proposed simplified model can
Li, GuangyuanChen, RunWang, XinranLi, TieZheng, KexiongLiu, ShaolingLiu, YanzhaoLyu, Xiaodong
The reliability and performance of steering systems in commercial vehicles are paramount, given their direct impact on reducing hazardous driving and improving operational efficiency. The torque overlay system is designed to enhance driver control, feedback, and reduce driver fatigue. However, vulnerabilities such as water ingress under certain environmental conditions have raised significant reliability requirements. This article discusses the systematic investigation into how radial bearing sideloading led to the input shaft seal failing to contact the input shaft. Water was allowed a path to enter the TOS module, affecting the electronic sensor, and faulting out the ADAS functionality. Improvement to the bearing support and sealing design culminated to an enhanced TOS module package able to withstand testing procedures that mimic the environmental and use case situation which caused the ingress.
Bari, Praful RajendraKintner, Jason
Optimizing the parameters of asymmetric textures (AT) designed on the surface of sliding frictional pairs (SFP) can make each texture more reasonably distributed. Thereby, the oil film thickness can be more stable; and the lubrication and load ability of SFP can be improved. To clarify this issue, based on the SFP’s lubricating model added by AT using the rectangular structure, parameters of AT including the angle between the horizontal axe and bottom surface (φij), the angle between the lateral axe and bottom surface (γij), and texture’s depth (hij) are optimized. The study results show that the parameters of φij, γij, and hij of AT optimized can create the p (hydrodynamic pressure of liquid) better than the symmetric textures. Significantly, the pmax and load ability of the liquid in the SFP using optimal AT have been greatly increased compared to the liquid in the SFP using the symmetric textures. Accordingly, the results are an important reference for the design and distribution of
Wang, CuifangZhang, Lu
Ethers are emerging as suitable mineral diesel replacements. A customized mechanical fuel injection system was used to investigate the dimethyl ether–fueled genset/tractor, and ~75% rated engine load was achieved over diesel. The in-cylinder pressure rise rate was about half for the dimethyl ether engine. However, the lower pressure generated in the high-pressure dimethyl ether line reduced brake thermal efficiency for the dimethyl ether engine. Dimethyl ether engines emitted lower nitrogen oxide emissions than baseline diesel except at higher loads and reduced nozzle opening pressure. Carbon monoxide emissions increased due to prolonged and incomplete combustion at higher loads with reduced nozzle opening pressure. Blowby gas leakage was lower for dimethyl ether than for baseline diesel engines. Overall, the genset/tractor engine could perform satisfactorily using a customized fuel injection system and will help achieve carbon neutrality from the various sectors using this technology.
Agarwal, Avinash KumarPal, ManojitValera, Hardikk
Public buses can be high-risk environments for the transmission of airborne viruses due to the confined space and high passenger density. However, advanced cabin air control systems and other measures can mitigate this risk. This research was conducted to explore various strategies aimed at reducing airborne particle transmission in bus cabins by using retrofit accessories and a redesigned parallel ventilation system. Public transit buses were used for stationary and on-road testing. Air exchange rates (ACH) were calculated using CO2 gas decay rates measured by low-cost sensors throughout each cabin. An aerosol generator (AG) was placed at various locations inside the bus and particle concentrations were measured for various experiments and ventilation configurations. The use of two standalone HEPA air filters lowered overall concentrations of particles inside the bus cabin by a factor of three. The effect of using plastic “barriers” independently showed faster particle arrival times
Lopez, BrendaSwanson, JacobDover, KevinRenck, EvanChang, M.-C. OliverJung, Heejung
This SAE Standard provides testing and functional requirements to meet specified minimum performance criteria for electronic probe-type leak detectors, so they will identify smaller refrigerant leaks when servicing all motor vehicle air conditioning systems, including those engineered with improved sealing and smaller refrigerant charges to address environmental concerns and increase system efficiency. This document does not address any safety issues concerning their design or use.
Interior Climate Control Service Committee
This SAE Recommended Practice is intended to establish a procedure to certify the fundamental driving skill levels of professional drivers. This certification can be used by the individual driver to qualify their skills when seeking employment or other professional activity. These certification levels may also be used by test facilities or other organizations when seeking test or professional drivers of various skills. The associated family of documents listed below establish driving skill criteria for various specific categories. SAE J3300: Driving level SAE J3300/1: Low mu/winter driving SAE J3300/2: Trailer towing SAE J3300/3: Automated driving Additional certifications to be added as appropriate. This main document provides: (1) common definitions and general guidance for using this family of documents, (2) directions for obtaining certification through Probitas Authentication®1, and (3) driving level examination requirements.
Driving Skills Standards Committee
A newly formulated fiber-based material was developed to offer a sustainable alternative to foam-based vehicle acoustic products. The fiber-based material was designed to be used in multiple vehicle acoustic applications, with different blends of the material available depending on the application. It performs well as an engine bay sound absorber due to its high heat tolerance and good absorption performance. A study was conducted to evaluate the sound absorption performance of this fiber-based material, specifically the engine bay blends, in comparison to that of current foam-based products. The results from this study show that the sound absorption performance of this new fiber-based material can match that of current foam-based materials while providing a sustainable and fully recyclable product, unlike the foam.
Krugh, Jack
Sound source identification based on beamforming is widely used today as a spatial sound field visualization technology in wind tunnel experiments for vehicle development. However, the conventional beamforming technique has its inherent limitation, such as bad spatial resolution at the low frequency range, and limited system dynamic range. To improve the performance, three deconvolution methods CLEAN, CLEAN-SC and DAMAS were investigated and applied to identify wind noise sources on a production car in this paper. After analysis of vehicle exterior wind noise sources distribution, correlation analysis between identified exterior noise sources and interior noise were conducted to study their energy contribution to vehicle interior. The results show that the algorithm CLEAN-SC based on spatial source coherence shows the best capability to remove the sidelobes for the uncorrelated wind noise sources, while CLEAN and DAMAS, which are based on point spread functions have definite
He, YinzhiShen, HenghaoWu, YuZhang, LijunYang, ZhigangBlumrich, ReinhardWiedemann, Jochen
This article follows a companion article [1] presented at the SAE NVC 2021, in which a new system for the measurement on small samples of the normal-incidence Insertion Loss (IL) of multilayers used for the manufacturing of automotive sound package parts was first introduced. In addition to simplifying the evaluation of the sound-insulation of multi-layers used to produce sound-package components, the system aims at overcoming the limitations of the test procedure based on the ASTM E2611 standard. In this article, the latter point is demonstrated by comparing the insertion loss results obtained with the new system with those obtained with the test procedure based on the ASTM E2611 standard on a few multilayers commonly used for the manufacturing of automotive sound package parts. Results indicate that the data obtained by means of the newly developed system are more meaningful, practically usable and less prone to edge-effects, compared to those obtained according to the ASTM E2611
Ruggeri, GiulioBertolini, ClaudioHorak, Jan
To predict the sound field produced by a vehicle horn requires a good source representation of it in the full vehicle model. This paper investigates the characterization of a physical vehicle horn by an inverse method called pellicular analysis. To implement this method, firstly an acoustic testing is performed to measure the sound pressure radiated from the horn at a certain number of microphone locations in a free field environment. Based on the geometry of a virtual horn, the locations of each microphone and measured sound pressure data, pellicular analysis is adopted to recover a set of vibration pattern of the virtual horn. The virtual horn and the recovered vibration information are then incorporated in a full vehicle numerical model to simulate its exterior sound field. The validity of this approach is confirmed by comparing the prediction for a horn in a production vehicle to the corresponding physical test which is required to meet the Brazilian regulation CONTRAN 764/2018.
Yang, WenlongMelo, Andre
A test and signal processing strategy was developed to allow a tire manufacturer to predict vehicle-level interior response based on component-level testing of a single tire. The approach leveraged time-domain Source-Path-Contribution (SPC) techniques to build an experimental model of an existing single tire tested on a dynamometer and substitute into a simulator vehicle to predict vehicle-level performance. The component-level single tire was characterized by its acoustic source strength and structural forces estimated by means of virtual point transformation and a matrix inversion approach. These source strengths and forces were then inserted into a simulator vehicle model to predict the acoustic signature, in time-domain, at the passenger’s ears. This approach was validated by comparing the vehicle-level prediction to vehicle-level measured response. The experimental model building procedure can then be adopted as a standard procedure to aid in vehicle development programs.
Nashio, HiroshiKajiwara, KoheiRinaldi, GiovanniSakamoto, Yumiko
As per metaphor, “The squeaky wheel gets the grease,” and in the case of Battery Electric Vehicles (BEVs), the transmission system has become the focal point for NVH (Noise, Vibration, and Harshness) improvements. With the engine being replaced by the near-silent electric motor, the noise generated by the transmission has become more prominent, demanding greater attention to noise reduction. This shift has created a pressing need for innovations in both design and manufacturing processes to enhance the overall quietness of the vehicle. As a result, ongoing advancements are being made to address and improve the NVH characteristics of BEV transmissions. Following paper will discuss the improvement in NVH achieved through a design innovation in the way bearings are installed and demonstrated a significant amount of improvement. We have used SMT MASTA as a simulation tool to predict the expected results and a Transmission Dyno test bench in an anechoic chamber to test the NVH performance
Pingale, AbhijeetSoni, Jaldeep
When a vehicle is driven at high speed, there exists intricate flow pattern and vortex shedding at the side window area with intense pressure fluctuation. A significant dynamic pressure difference between the vehicle's exterior and interior can render the side window sealing system vulnerable to aspiration. This susceptibility can lead to the generation of leakage noise, adversely affecting acoustic comfort in the vehicle's cabin. This paper delves into the aspiration properties of glassrun seal system under time-varying pressure difference. A nonlinear finite element model of the glassrun seal was established to simulate the quasi-static deformation of the sealing strip during installation process, which aims to obtain the deformed geometric shape and residual stress after this process. Then, the exterior flow field of the glassrun sealing area of a simplified vehicle model was calculated with CFD simulation to obtain the hydrodynamic pressure excitation acting on the outer surface of
Li, HanqiHe, YinzhiZhang, LijunZhang, YongfengYu, WuzhouJiang, ZaixiuBlumrich, ReinhardWiedemann, Jochen
Damping treatments play a key role in the definition of efficient acoustic packages for passenger cars with all types of propulsion systems. Many damper configurations are similar for all vehicles including treatments of wheelhouses, spare wheel area, roof panels etc. However, there are some characteristics of car body acoustics in electric vehicles, which need to be considered in the definition of the efficient damping package. This paper investigates the impact of the high voltage (HV) battery on interior noise related characteristics of the car body using laser scanning vibrometry (LSV) and 3D sound intensity test methods. It is shown that both methods lead to similar conclusions in terms of proper distribution of damping material. Furthermore, findings are used in the damping package case study resulting in two additional proposals of the damping layout with different lightweight and acoustic requirements. Lab evaluation of the new damping package variants are conducted by laser
Unruh, OliverGielok, Martin
High-frequency whine noise in electric vehicles (EVs) is a significant issue that impacts customer perception and alters their overall view of the vehicle. This undesirable acoustic environment arises from the interaction between motor polar resonance and the resonance of the engine mount rubber. To address this challenge, the proposal introduces an innovative approach to predicting and tuning the frequency response by precisely adjusting the shape of rubber flaps, specifically their length and width. The approach includes the cumulation of two solutions: a precise adjustment of rubber flap dimensions and the integration of ML. The ML model is trained on historical data, derived from a mixture of physical testing conducted over the years and CAE simulations, to predict the effects of different flap dimensions on frequency response, providing a data-driven basis for optimization. This predictive capability is further enhanced by a Python program that automates the optimization of flap
Hazra, SandipKhan, Arkadip
Rotor skewing is a commonly used technique to mitigate noise and vibration challenges of permanent magnet synchronous motor. The intention of rotor skewing is to minimize targeted electromagnetic forces, thereby enhancing motor NVH performance. However, achieving improved NVH performance may be attainable by merely altering the rotor skew pattern while keeping the summation of radial and tangential electromagnetic forces the same. This research investigates the impact of different rotor skewing patterns on the NVH performance of permanent magnet synchronous motor. With summation of radial and tangential electromagnetic forces remaining the same, four different skew patterns are applied to generate electromagnetic forces across each motor slice. Multi-slice method is used for different skew patterns when applying electromagnetic forces on the motor model. Noise and vibration level will be compared to identify the best skew pattern for proposed motor.
Chen, KeyuWang, WeiMa, CongHartwig, MarcusNarayanan, Arun
Platform based vehicle development is standardized at John Deere. The challenges of frontloading the integration of individual components within different platforms using predictive methods is key to shortening the development cycle. Components are individually characterized on test benches and results cannot directly be used to evaluate system performance. Invariant characterization is needed instead, which is possible through techniques such as blocked loads estimation. To evaluate the applicability of such methods, the component-based loads and vehicle in-situ operational loads need to be compared. The confident use of these methods for obtaining structural and acoustic loads enables the use of hybrid system models, enhancing early NVH response predictions. The objective of this work was to enable the confident use of test stand measurements in predictive models across various vehicle platforms. This study compares a powertrain characterization in a vehicle against a test stand to
Vesikar, Prasad BalkrishnaEdgington, JasonDrabison II, John
The implementation of active sound design models in vehicles requires precise tuning of synthetic sounds to harmonize with existing interior noise, driving conditions, and driver preferences. This tuning process is often time-consuming and intricate, especially facing various driving styles and preferences of target customers. Incorporating user feedback into the tuning process of Electric Vehicle Sound Enhancement (EVSE) offers a solution. A user-focused empirical test drive approach can be assessed, providing a comprehensive understanding of the EVSE characteristics and highlighting areas for improvement. Although effective, the process includes many manual tasks, such as transcribing driver comments, classifying feedback, and identifying clusters. By integrating driving simulator technology to the test drive assessment method and employing machine learning algorithms for evaluation, the EVSE workflow can be more seamlessly integrated. But do the simulated test drive results
Hank, StefanKamp, FabianGomes Lobato, Thiago Henrique
In this work, Genetic Algorithm (GA) optimized Proportional Integral Derivative (PID) controller is employed in the active suspension. The PID gain values are optimally tuned based on the objective function by the Integral Time Absolute Error (ITAE) criteria of various suspension measures like vehicle body displacement, suspension and tire deflections. The proposed GAPID controller is experimentally validated through the 3-DOF quarter-car (QC) test rig model. The fabricated model with passive suspension system (PASS) and active suspension system (ACSS) with an electrical actuator is presented. The schematic representation of the fabricated test set-up with and without ACSS is also illustrated. Further, simulation and experimental response of the fabricated model with and without ACSS are compared. It is identified that the proposed GAPID controller attenuates the sprung mass acceleration by about 41.64 % and 29.13 % compared with PASS for the theoretical as well as experimental cases
A, ArivazhaganKandavel, Arunachalam
The arrangement of error microphones for a vehicle active noise control (ANC) system is no trivial work, especially for heavy-duty trucks, due to the dilemma resulted from the large volume of the cab and the limited number of microphones accepted by most manufacturers in the auto industry. Although some pioneering work has laid the foundation for the application of numerical methods exemplified by the genetic-algorithm (GA) to optimize the error sensor arrangement in an ANC system, most ANC developers still resort to trial and error in practice, which is not only a heavy workload given the amount of interested working conditions to be tested, but also does not guarantee to yield the optimum noise cancellation performance. In this paper, the authors designed and implemented an error microphone selection process using a genetic-algorithm (GA) -based mechanism. The target vehicle was a heavy-duty truck with a six-piston diesel engine, and two application scenarios were particularly
Wang, JianLing, ZihongZhang, ZheCai, DeHualv, XiaoZhang, MingGao, GuoRan
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