Browse Topic: Materials

Items (64,528)
Reduction of frictional losses by changing the surface roughness in the form of surface textures has been reported as an effective method in reducing friction in the boundary regime of lubrication. Laser-based micro texturing has been mostly used to create these texture patterns and it is reported that it can reduce the frictional resistance by ~20-50%. However, the use of laser-based techniques for texture preparation led to residual thermal stress and micro cracks on the surfaces. Hence, the current study emphasizes using conventional micromachining on piston material (Al alloy Al4032) to overcome this limitation. Three variations of semi-hemispherical geometries were prepared on the surface of Al alloy with dimple depths of 15, 20 and 40 μm and dimple diameters of 90, 120 and 240 μm. Prepared textured surfaces with untextured surfaces are compared in terms of wear, wettability, and friction characteristics based on Stribeck curve behaviors. Results of this investigation demonstrated
Sahu, Vikas KumarShukla, Pravesh ChandraGangopadhyay, Soumya
Continuing prior work, which established a simulation workflow for fatigue performance of elastomeric suspension bushings operating under a schedule of 6-channel (3 forces + 3 moments) road load histories, the present work validates Endurica-predicted fatigue performance against test bench results for a set of multi-channel, time-domain loading histories. The experimental fatigue testing program was conducted on a servo-hydraulic 3 axis test rig. The rig provided radial (cross-car), axial (for-aft), and torsional load inputs controlled via remote parameter control (rpc) playback of road load data acquisition signals from 11 different test track events. Bushings were tested and removed for inspection at intervals ranging from 1x to 5x of the test-equivalent vehicle life. Parts were sectioned and checked for cracks, for point of initiation and for crack length. No failure was observed for bushings operated to 1 nominal bushing lifetime. After 3 nominal bushing lifetimes, cracks were
Mars, WillBarbash, KevinWieczorek, MatthewPham, LiemBraddock, ScottSteiner, EthanStrumpfer, Scott
New highly ductile advanced high strength steel (AHSS) grades with tensile strength greater than 980 MPa have been developed with the aim of achieving a combination of high strength and excellent formability. The new jetQTM-Family [1, 2] offers high local and global ductility, which is expected to contribute to the improvement of vehicle crash performance. For the reliable design and management of vehicle crash performance, material modeling, including work hardening behavior and material failure strain, plays an important role in numerical simulation. Especially, the accuracy of material failure prediction is important for the development of crash performance. In this study, the fracture behaviors of 980jetQTM, 1180jetQTM, and conventional Dual-Phase (DP) steels are investigated through simple tensile and V-bending fracture tests incorporating experimental-numerical hybrid ductile fracture analysis. Based on the experimental results, the ductile fracture parameters in the Hosford
Sato, KentaroSakaidani, TomohiroOhnishi, YoichiroPaton, AdrianRoesen, Hartwig
According to several precedent studies, most of the cold-forming advanced high-strength steel (AHSS) grades can obtain reinforced yield strength from the automotive forming and paint-baking treatments without losing their fracture resistance like some aluminum alloys. Concisely, the mechanism of such behavior can be mainly attributed to the ‘Cottrell Atmospheres,’ some thermally mobilized interstitial atoms that cluster around and impede mobile dislocations during only the yielding stage of the plastic deformation but cannot continue durably enough to affect the fracture. Nevertheless, an exception, Q&P1180, was discovered from precedent studies and characterized in this work. Different from other AHSSs, this grade exhibited distinctively elevated fracture resistance and yield strength after the pre-straining and baking. Such uniqueness was speculated to be caused by 1) no soft ferrite in the microstructure and 2) the transformed fresh martensite induced by the plastic deformation
Hu, JunSun, YetingThomas, Grant
Depletion of petroleum crude oil and its environmental impacts challenge future generations. Vegetable oils provide a sustainable alternative with benefits like anti-wear properties, biodegradability, and renewability. Kusum oil's ability to lower carbon emissions significantly and promote sustainable industrial practices highlights its potential as a viable green alternative. This research paper presents a comprehensive and comparative analysis of a sustainable, environmentally friendly bio-lubricant and nonedible vegetable oil like Kusum oil. Bio-lubricant is produced by transesterification followed by epoxidation, which is known as epoxidized kusum oil lubricant or dehydrated kusum oil (DKO). The process of epoxidation significantly enhances the properties of Kusum oil, making it a promising alternative to conventional lubricants. It is compared with a widely used conventional mineral oil lubricant like SAE10W40. DKO exhibits comparable density, viscosity index, pour point, and
Prabhakaran, JPali, Harveer SinghSingh, Nishant K.
Due to advantages such as high efficiency, low emissions, and fuel flexibility, solid oxide fuel cells (SOFCs) have garnered significant attention as promising power sources for automotive applications. Nickel/yttria-stabilized zirconia (Ni/YSZ) is one of the most widely used anode materials in SOFCs, as it can catalyze both chemical and electrochemical reactions of carbon-containing fuels. However, the direct use of carbon-containing fuels can lead to carbon deposition on the Ni/YSZ anode, negatively impacting the performance and reliability of automotive SOFC systems. The diffusion of carbon atoms within nickel plays a crucial role in the carbon deposition process and requires further investigation. The oxygen atoms that spillover from YSZ also participate in main reactions such as carbon deposition and electrochemical reactions in Ni. Molecular dynamics (MD) is one of the main methods for studying atomic diffusion in crystalline structures. In this study, reactive force field
Du, HaoyuZhang, KaiqiXiao, MaZhang, XiaoqingShuai, Shijin
The current ASTM A653 standard for determining the bake hardening index (BHI) of sheet metals can lead to premature fracture at the transition radius of the tensile specimen in high strength steel grades. In this study, a new test procedure to characterize the BHI was developed and applied to 980 and 1180 MPa third generation advanced high strength steels (3G-AHSS). The so-called KS-1B methodology involves pre-straining over-sized tensile specimens followed by the extraction of an ASTM E8 sample, paint baking and re-testing to determine the BHI. Various pre-strain levels in the range of 2 to 10% were considered to evaluate the KS-1B procedure with select comparisons with the ASTM A653 methodology for pre-strain levels of 2 and 8%. Finally, to characterize the influence of paint baking at large strain levels, sheared edge conical hole expansion tests were conducted. The tensile mechanical properties of the 3G steels after paint baking were observed to be sensitive to the pre-strain with
Northcote, RhysBerry, AvalonNarayanan, AdvaithTolton, CameronLee, HaeaSmith, JonathanMcCarty, EricButcher, Cliff
Utilization of fiber-reinforced composite laminates to their full potential requires consideration of angle-ply laminates in structural design. This category of laminates, in comparison with orthotropic laminates, imposes an additional degree of challenge, due to a lack of material principal axes, in determination of elastic laminate effective properties if the same has to be done experimentally. Consequentially, there is a strong inclination to resort to the usage of “CLPT” (Classical Laminated Plate Theory) for theoretically estimating the linear elastic mechanical properties including the cross-correlation coefficients coupling normal and shear effects. As an angle-ply laminate is architecturally comprised of layers of biased orthotropic laminas (based on unidirectional or woven bidirectional fibers), an essential prerequisite for the application of CLPT is an a-priori knowledge of elastic mechanical properties of a constituent lamina. It is natural to expect that the properties of
Tanaya, SushreeDeb, Anindya
As global warming and environmental problems are becoming more serious, tires are required to achieve a high level of performance trade-offs, such as low rolling resistance, wet braking performance, driving stability, and ride comfort, while minimizing wear, noise, and weight. However, predicting tire wear life, which is influenced by both vehicle and tire characteristics, is technically challenging so practical prediction method has long been awaited. Therefore, we propose an experimental-based tire wear life prediction method using measured tire characteristics and the wear volume formula of polymer materials. This method achieves practical accuracy for use in the early stages of vehicle development without the need for time-consuming and costly real vehicle tests. However, the need for improved quietness and compliance with dust regulations due to vehicle electrification requires more accuracy, leading to an increase in cases requiring judgment through real vehicle tests. To address
Ando, Takashi
In sheet metal simulation, computation time is significantly influenced by the number of elements used to discretize the sheet blank, which covers the shape of forming tool geometry. Based on particle kinematics, motion of material point is modeled, and the concept of zero circumferential motion material line (ZML) is proposed. The slope ratio of material line (SRML) is proposed to quantify the circumferential deviation for determining the ZML. Based on the SRML, a method is developed to segment sheet blank and apply constraints. The method is demonstrated through forming simulation on a Hishida geometry. The proposed method, with its minimal to no circumferential motion along ZMLs, exhibits high level of accuracy retention while simultaneously impressively reducing computation time (up to 77%). This combination of efficiency and precision makes it a compelling approach for reducing simulation cost.
Sheng, ZiQiangAsimba, BrianCabral, Kleber
Track testing methods are utilized in the automotive industry for emissions and fuel economy certification. These track tests are performed on smooth road surfaces which deteriorate over time due to wear and weather effects, hence warranting regular track repaves. The study focuses on the impact of repaving on track quality and surface degradation due to weather effects. 1D surface profiles and 2D surface images at different spatial frequencies were measured at different times over a span of two years using various devices to study the repave and degradation effects. Data from coastdown tests was also collected over a span of two years and is used to demonstrate the impact of track degradation and repaving on road load characterization parameters that are used for vehicle certification tests. Kernel density estimation and non-parametric spectral estimation methods are used to visualize the characteristic features of the track at different times. In the pre-processing stage, outliers
Singh, YuvrajJayakumar, AdithyaRizzoni, Giorgio
The use of lithium-ion batteries in electric vehicles marks a major progression in the automotive sector. Energy storage systems extensively make use of these batteries. The extended life cycle, low self-discharge rates, high energy density, and eco-friendliness of lithium-ion batteries are well-known. However, Temperature sensitivity has an adverse effect on lithium-ion battery safety, durability, and performance. Thus, maintaining ideal operating conditions and reducing the chance of thermal runaway depend heavily on efficient thermal management. To address this, experimental study was conducted on various battery thermal management techniques, including active, passive, and hybrid approaches. These techniques were investigated for their cooling efficiencies under different operating conditions. The electro-thermal behavior of cylindrical lithium-ion battery cells, battery packs, and supervisory control techniques were simulated in the study using MATLAB Simulink, Simscape, and
Thangaraju, ShanmuganathanN, MeenakshiGanesan, Maragatham
Blistering in aesthetic parts poses a significant challenge, affecting overall appearance and eroding brand image from the customer's perspective and blister defects disrupt painting line efficiency, resulting in increased rework and rejection rates. This paper investigates the causes and effects of blistering, particularly in the context of internal soundness of Aluminum castings, emphasizing the crucial role of Computed Tomography in defect analysis. Computed Tomography is an advanced Non-Destructive Testing technique used to examine the internal soundness of a material. This study follows a structured 7-step QC story approach, from problem identification to standardization, to accurately identify the root Cause and implement corrective actions to eliminate blister defect. The findings reveal a strong link between internal soundness and surface quality. Based on the root cause, changes in the casting process and die design were made to improve internal soundness, leading to reduced
D, BalachandarNataraj, Naveenkumar
To obtain real-time tire wear status during vehicle operation, this paper proposes a tire wear detection method based on signal analysis. Firstly, PVDF piezoelectric thin film sensors are pasted in the center of the airtight layer of tires with different degrees of wear to collect tire stress data under different working conditions. Secondly, filter and extract the time-domain and frequency-domain feature information of the collected data to construct a feature dataset. Finally, a deep regression model is established to train the feature dataset and achieve real-time detection of tire damage status. The results indicate that the prediction algorithm based on signal analysis and feature extraction achieves a maximum error of 0.3mm in tire wear detection, demonstrating high accuracy in tire wear detection. Providing tire information for safe driving of vehicles has high industrial application value.
Xianyi, XieYang, HaoJin, Lisheng
Plastic waste, in the past few years, has risen to be one of the most concerning and endangering pollutants to environment and life, making its effective management and reduction a major domain of focus among researchers and industrialists. This comparative study is an attempt to utilize recycled Polyethylene Terephthalate (rPET) fibres combined with Epoxy Resin in various combinations, to provide effective and low-cost insulation in moderate to low requirements. The above-mentioned components serve as viable insulators. Moisture resistance of both materials and temperature resistance of Epoxy resins ranging from 120°C to 150°C (depending upon the grade of Epoxy used) indicate a good stability in harsh external operating environment. While Epoxy resins are not inherently flame retardants, additives are introduced for this purpose in order to render the composite safer to use. Owing to the excellent adhesive properties of the Epoxy resin, the rPET fibres are allowed to bond together
Purihella, Sri Sai KrishnaPali, Harveer SinghKumar, PiyushSharma, Ved Prakash
The mechanical properties of materials play a crucial role in real life. However, methods to measure these properties are usually time-consuming and labour intensive. Small Punch Through (SPT) has non-destructive characteristics and can obtain load-displacement curves of specimens, but it cannot visually extract the mechanical properties of materials. Therefore, we designed a proprietary SPT experiment and fixture, built a finite element method (FEM) model and developed a multi-fidelity model capable of predicting the mechanical properties of steel and aluminium alloys. It makes use of multi-fidelity datasets obtained from SPT and FEM simulation experiments, and this integration allows us to support and optimize the predictive accuracy of the study, thus ensuring a comprehensive and reliable characterization of the mechanical properties of the materials. The model also takes into account variations in material thickness and can effectively predict the mechanical properties of materials
Zou, JieChen, YechaoLi, ShanshanHuayang, Xiang
Three-way catalysts (TWCs) containing significant amounts of precious metals are commonly employed to purify exhaust emissions (CO, NOx, and THC) from gasoline-powered vehicles. A critical factor contributing to TWC degradation is the sintering of these precious metals. Maintaining the appropriate particle size and distribution of the metals is essential for optimal catalyst performance. In this study, palladium (Pd) nanoparticles with a uniform size were synthesized using ethylene glycol as a reductant under ultrasonic conditions, yielding particles in the range of 3 nm to 5 nm. These Pd nanoparticles were subsequently used to prepare three-way catalysts on cordierite substrates supplied by Corning (China) Inc. Chemisorption analysis revealed that the Pd active component in the catalysts prepared via the ultrasonic method exhibited higher dispersion than the state-of-the-art commercial catalysts. The aged catalysts were obtained after 150 hours of aging following the General Motors
Hao, ShijieLv, YananWang, WeidongRao, ChaoWei, WeiMao, BingbinChen, TaoZhao, Huawang
Aluminum oxide (Al₂O₃) nanoparticles are considered a promising fuel additive to enhance combustion efficiency, reduce emissions, and improve fuel economy. This study investigates the spray characteristics of diesel fuel blended with aluminum oxide nanoparticles in a constant volume chamber. The blends were prepared by dispersing Al₂O₃ nanoparticles in diesel at varying concentrations (25, 50, and 100 mg of aluminum oxide nanoparticles into 1 L of pure diesel, respectively) using a magnetic stirrer and ultrasonication to ensure stable suspensions. Spray characterization was conducted in a high-pressure and high-temperature constant volume chamber, simulating actual engine conditions. The ambient temperatures for this experiment were set from 800 to 1200 K, and the oxygen concentrations were set from 21% to 13%. The study focused on key spray parameters such as spray penetration length, spray angle, and spray area, analyzed using high-speed imaging and laser diffraction techniques
Ji, HuangchangZhao, Zhiyu
Any vehicle traveling on roads interacts with various profiles of surface roughness, which can be best characterized by randomness. The resulting random vibrations not only expose passengers to unpleasant physical shakes and noises, but also impart fatigue damage to nearly everything installed on the vehicle. In today’s robust design process, it is highly desirable to predict fatigue damage in the early design phase, in order to prevent any durability problems in the future, especially for electric vehicles. Historically, the conventional approach to tackling the problem of fatigue damage has involved cycle-counting stress or strain responses, obtained through step-by-step numeric solutions in the time-domain. However, the most effective method of predicting fatigue in random vibration lies in the frequency domain. Such a spectrum-based approach is greatly advantageous because it does not have to deal with expensive and tedious simulations involving millions of time instants of
Yang, ZaneFouret, Charles
Mechanical analysis was performed of a non-pneumatic tire, specifically a Michelin Tweel size 18x8.5N10, that can be used up to a speed of 40 km/h. A Parylene-C coating was added to the rubber spoke specimens before performing both microscopic imaging and cyclic tensile testing. Initially, standard ASTM D412 specimens type C and A were cut from the wheel spokes, and then the specimens were subjected to deposition of a nanomaterial. The surfaces of the specimens were prepared in different ways to examine the influence on the material behavior including the stiffness and hysteresis. Microscopic imaging was performed to qualitatively compare the surfaces of the coated and uncoated specimens. Both coated and uncoated spoke specimens of each standard type were then subjected to low-rate cyclic tensile tests up to 500% strain. The results showed that the Parylene-C coating did not affect the maximum stress in the specimens, but did increase the residual strain. Type C specimens also had a
Collings, WilliamLi, ChengzhiSchwarz, JacksonLakhtakia, AkhleshBakis, CharlesEl-Sayegh, ZeinabEl-Gindy, Moustafa
Image-based machine learning (ML) methods are increasingly transforming the field of materials science, offering powerful tools for automatic analysis of microstructures and failure mechanisms. This paper provides an overview of the latest advancements in ML techniques applied to materials microstructure and failure analysis, with a particular focus on the automatic detection of porosity and oxide defects and microstructure features such as dendritic arms and eutectic phase in aluminum casting. By leveraging image-based data, such as metallographic and fractographic images, ML models can identify patterns that are difficult to detect through conventional methods. The integration of convolutional neural networks (CNNs) and advanced image processing algorithms not only accelerates the analysis process but also improves accuracy by reducing subjectivity in interpretation. Key studies and applications are further reviewed to highlight the benefits, challenges, and future directions of
Akbari, MeysamWang, AndyWang, QiguiYan, Cuifen
This study numerically analyzed the gas diffusion layer (GDL) in proton exchange membrane fuel cells (PEMFCs). The GDL, composed of carbon fibers and binder, plays a critical role in facilitating electron, heat, gas, and water transport while cushioning under cell compression. Its microstructure significantly influences these properties, requiring precise design. Using simulations, this study explored GDL designs by varying fiber and binder parameters and calculated gas diffusivity under wet conditions. Unlike previous studies, a novel model treated carbon fibers as beam elements with elastic binder connections, closely replicating structural changes under compression. Key properties analyzed include permeability, electrical conductivity, and gas diffusion efficiency under wet conditions. The optimized designs enhanced these properties while balancing trade-offs between electrical conductivity and mass transport. These findings provide valuable guidelines for advancing PEMFC technology
Ota, YukiDobashi, ToshiyukiNomura, KumikoHattori, TakuyaMaekawa, Ryosuke
The linear region of the side-slip mechanical properties of tires is often used in the simulation of linear monorail models for vehicles, especially in the design of active control systems. Side-slip stiffness is a key parameter in tire side-slip, and is significantly influenced by camber and load. In response to the tire industry's need for efficient acquisition of tire mechanical properties and the development of virtual prototyping technology, this paper proposes a method to address the influence mechanism of camber on side-slip in the study of tire camber side-slip prediction models. This paper analyzes the impact of camber on the linear region of tire side-slip mechanical properties at the microscopic level. It then examines the effect of camber on the side-slip condition from the perspective of tire external characteristics, combined with the tire theoretical model, to map the local characteristics of camber onto the external characteristics of tire side-slip. First, a finite
Yin, HengfengSuo, YanruWu, HaidongMin, HaitaoLiu, Dekuan
The advancement of high-performance electrification for electric vehicle (EV) development is continuously pushing the boundaries of electric motor technology. The axial flux motor (AFM) represents a promising application for high-performance EVs, offering potential advantages including up to twice the torque density and a 50% reduction in weight compared to regular IPM radial flux motors. The distinctive "pancake" configuration and high axial forces inherent to AFMs present notable NVH challenges, yet there is a lack of research exploring NVH analysis and risk assessment. In this paper, a 10-pole and 12-slot AFM motor is designed, prototyped, and tested, demonstrating the capability to deliver 320 Nm of peak torque and 140 kW of peak power. A comprehensive finite-element model is constructed, and the orthotropic stator material properties are evaluated using modal test data. The dominant axial stator modes are identified as the source of resonances in the system responses. A three
He, SongJensen, WilliamForsyth, AlexanderChang, LeZhang, PengGong, ChengYao, JianZou, YushengFedida, VincentDuan, ChengwuGSJ, Gautam
In order to comply with the tightening of global regulations on automobile exhaust gas, further improvements to exhaust gas control catalysts and upgrades to on-board diagnostics (OBD) systems must be made. Currently, oxygen storage capacity (OSC) is monitored by front and rear sensors before and after the catalyst, and deterioration is judged by a decrease in OSC, but it is possible that catalyst deterioration may cause the rear sensor to detect gas that has not been sufficiently purified. It is important to observe the activity changes when the catalyst deteriorates in more detail and to gain a deeper understanding of the catalyst mechanism in order to create guidelines for future catalyst development. In this study, we used a μ-TG (micro thermogravimetric balance) to analyze in detail how differences in design parameters such as the type of precious metal, detection temperature, and mileage (degree of deterioration) affect the OSC rate in addition to the OSC of the ceria-based
Hamada, ShotaUegaki, ShinyaTanabe, HidetakaNakayama, TomohitoJinjo, ItsukiKurono, SeitaOishi, ShunsukeNarita, KeiichiOnishi, TetsuroYasuda, KazuyaMatsumura, DaijuTanaka, Hirohisa
Plasticized polyvinyl chloride (PVC) has many applications in automotive industry including electrical harnesses, door handles, seat and head rest covers, and instrument panel (IP) and other interior trim. In IP applications, the PVC skin plays a critical role in passenger airbag deployment (PAB) by tearing along the scored edge of the PAB door and allowing the door to open and the airbag to inflate to protect the occupant. As part of the IP, the PVC skin may be exposed to elevated temperatures and ultraviolet (UV) radiation during the years of the vehicle life cycle which can affect the PVC material properties over time and potentially influence the kinematics of the airbag deployment. Chemical and thermal aging of plasticized PVC materials have been studied in the past, yet no information is found on how the aging affects mechanical properties at high rates of loading typical for airbag deployment events. This paper compares mechanical properties of the virgin PVC-based IP skin
G, KarthiganSavic, VesnaRavichandran, Gowrishankar
Electric vehicles (EVs) are particularly susceptible to high-frequency noise, with rubber eigenmodes significantly influencing these noise characteristics. Unlike internal combustion engine (ICE) vehicles, EVs experience pronounced variations in dynamic preload during torque rise, which are substantially higher. This dynamic preload variation can markedly impact the high-frequency behaviour of preloaded rubber bushings in their installed state. This study investigates the effects of preload and amplitude on the high-frequency dynamic performance of rubber bushings specifically designed for EV applications. These bushings are crucial for vibration isolation and noise reduction, with their role in noise, vibration, and harshness (NVH) management being more critical in EVs due to the absence of traditional engine noise. The experimental investigation examines how preload and excitation amplitude variations influence the dynamic stiffness, damping properties, and overall performance of
Hazra, SandipKhan, Arkadip Amitava
Electric vehicles (EVs) are gaining popularity due to their zero tailpipe emissions, superior energy efficiency, and sustainable nature. EVs have various limitations, and crucial one is the occurrence of thermal runaway in the battery pack. During charging or discharging condition of battery pack may result in thermal runaway condition. This promotes the requirement of effective cooling arrangement in and around the battery pack to avoid localized peak temperature. In the present work, thermal management of a 26650 Lithium iron phosphate (LFP) cell using natural convection air cooling, composite biobased phase change material (CBPCM) and its combination with copper fins is numerically investigated using multi-scale multi dimension - Newman, Tiedenann, Gu and Kim (MSMD-NTGK) battery model in Ansys Fluent at an ambient temperature of 306 K. Natural convection air cooling was found effective at discharge rates of 1C to 3C, maintaining cell temperature below the safe limit of 318 K for 80
Srivastav, DurgeshPatil, Nagesh DevidasShukla, Pravesh Chandra
On-board diagnosis (OBD) of gasoline vehicle emissions is detected by measuring the fluctuations of the rear oxygen sensor due to the time-dependent deterioration of the oxygen storage capacity (OSC) contained in the automotive catalyst materials. To detect OBD in various driving modes of automobiles with an order of magnitude higher accuracy than before, it is essential to understand the OSC mechanism based on fundamental science. In this study, time-resolved dispersive X-ray absorption fine structure (DXAFS) using synchrotron radiation was used to carry out a detailed analysis not only of the OSC of ceria-based complex oxides, which had previously been roughly understood, but also of how differences in design parameters such as the type of precious metals, reducing gases (CO and H2), detection temperatures, and mileages (degree of deteriorations) affect the OSC rate in a fluctuating redox atmosphere. A fundamental characteristic was clearly demonstrated in ceria-based complex oxides
Tanaka, HirohisaMatsumura, DaijuUegaki, ShinyaHamada, ShotaAotani, TakuroKamezawa, SaekaNakamoto, MasamiAsai, ShingoMizuno, TomohisaTakamura, RikuGoto, Takashi
This study investigates the influence of magnetorheological (MR) dampers in semi-active suspension systems (SASSs) on ride comfort, vehicle stability, and overall performance. Semi-active suspension systems achieve greater flexibility and efficacy by combining MR dampers with the advantages of active and passive suspension systems. The study aims to measure the benefits of MR dampers in improving ride comfort, vehicle stability, and overall system performance. The dynamic system model meets all required performance criteria. This study demonstrates that the proposed artificial intelligence approach, including a fuzzy neural networks proportional-integral-derivative (FNN-PID) controller, significantly enhances key performance criteria when tested under various road profiles. The control performance requirements in engineering systems are evaluated in the frequency and time domains. A quarter-car model with two degrees of freedom (2 DOF) was simulated using MATLAB/Simulink to assess the
M.Faragallah, MohamedMetered, HassanAbdelghany, M.A.Essam, Mahmoud A.
Automotive chassis components are considered as safety critical components and must meet the durability and strength requirements of customer usage. The cases such as the vehicle driving through a pothole or sliding into a curb make the design (mass efficient chassis components) challenging in terms of the physical testing and virtual simulation. Due to the cost and short vehicle development time requirement, it is impractical to conduct physical tests during the early stages of development. Therefore, virtual simulation plays the critical role in the vehicle development process. This paper focuses on virtual co-simulation of vehicle chassis components. Traditional virtual simulation of the chassis components is performed by applying the loads that are recovered from multi-body simulation (MBD) to the Finite Element (FE) models at some of the attachment locations and then apply constraints at other selected attachment locations. In this approach, the chassis components are assessed
Behera, DhirenLi, FanTasci, MineSeo, Young-JinSchulze, MartinKochucheruvil, Binu JoseYanni, TamerBhosale, KiranAluru, Phani
In the automotive industry, it is essential to consider not only how well specialty materials perform and are formulated, but also how efficiently and economically they can be applied during manufacturing. This becomes especially important during the early stages of development to prevent issues when these materials are used in new designs by automotive suppliers or manufacturers. With the rapid growth of electric vehicles (EVs), new materials are being used more frequently, and these materials may not have been as thoroughly tested as those used in traditional internal combustion engine (ICE) vehicles. Therefore, it is crucial to ensure that these materials can be applied correctly and efficiently from the start. One way to speed up the development process is through Computational Fluid Dynamics (CFD) modeling. CFD helps predict how materials will behave when dispensed, which is essential for developing the right equipment and conditions for applying these materials. Working with
Kenney, J. AndyDelgado, RobertoHossain, ArifNg, Sze-SzeThomas, RyanChyasnavichyus, MariusTsang, Chi-WeiHwang, MargaretWu, LanceDietsche, LauraMcmichael, JonathanRaines, KevinNelson, Grant
The half vehicle spindle-coupled multi-axial input durability test has been broadly used in the laboratory to evaluate the fatigue performance of the vehicle chassis systems by automotive suppliers and OEMs. In the lab, the front or rear axle assembly is usually held by fixtures at the interfaces where it originally connects to the vehicle body. The fixture stiffness is vital for the laboratory test to best replicate the durability test in the field at a full vehicle level especially when the subframe of the front or rear axle is hard mounted to the vehicle body. In this work, a multi-flexible body dynamics (MFBD) model in Adams/Car was utilized to simulate a full vehicle field test over various road events (rough road, braking, steering). The wheel center loads were then used as inputs for the spindle coupled simulations of the front axle with a non-isolated subframe. Three types of fixtures including trimmed vehicle body, a rigid fixture with softer connections and a rigid fixture
Gao, JianghuaSmith, DerekZhang, XinYu, Xiao
Many methods have been proposed to accurately compute a vehicle’s dynamic response in real-time. The semi-recursive method, which models using relative coordinates rather than dependent coordinates, has been proven to be real-time capable and sufficiently accurate for kinematics. However, not only kinematics but also the compliance characteristics of the suspension significantly impact a vehicle’s dynamic response. These compliance characteristics are mainly caused by bushings, which are installed at joints to reduce vibration and wear. As a result, using relative or joint coordinates fails to account for the effects of bushings, leading to a lack of compliance characteristics in suspension and vehicle models developed with the semi-recursive method. In this research, we propose a data-driven approach to model the compliance characteristics of a double wishbone suspension using the semi-recursive method. First, we create a kinematic double wishbone suspension model using both the semi
Zhang, HanwenDuan, YupengZhang, YunqingWu, Jinglai
Camera-based mirror systems (CBMS) are being adopted by commercial fleets based on the potential improvements to operational efficiency through improved aerodynamics, resulting in better fuel economy, improved maneuverability, and the potential improvement for overall safety. Until CBMS are widely adopted it will be expected that drivers will be required to adapt to both conventional glass mirrors and CBMS which could have potential impact on the safety and performance of the driver when moving between vehicles with and without CBMS. To understand the potential impact to driver perception and safety, along with other human factors related to CBMS, laboratory testing was performed to understand the impact of CBMS and conventional glass mirrors. Drivers were subjected to various, nominal driving scenarios using a truck equipped with conventional glass mirrors, CBMS, and both glass mirrors and CBMS, to observe the differences in metrics such as head and eye movement, reaction time, and
Siekmann, AdamPrikhodko, VitalySujan, Vivek
The flow resistivity is a critical parameter for evaluating the acoustic performance of the porous materials. Accurate determination of flow resistivity is essential for predicting the characteristic impedance and propagation constants of materials. In this paper, a method is proposed to calculate the flow resistivity of kapok fiber felt, aiming to accurately assess the flow resistivity of kapok fiber felt. Based on the dual-porosity equivalent model of kapok fiber felt, it is hypothesized that the flow resistivity is divided into two components. One part from the large pores between fibers, and the other part from the hollow structures within kapok fibers and the micropores on the fiber walls. The contribution of the large pores between fibers to the flow resistivity is calculated using the Tarnow_S model. Meanwhile, the hollow pores within the kapok fibers and the micropores on the fiber walls are represented as an equivalent pore. The slip effects are considered, and experimental
Lin, JiamanKang, YingziXie, XinxingZhang, QuYang, ShanmiaoShangguan, Wen-Bin
The integrated bracket is a plastic part that packages functional components such as the ADAS (Advanced Driver Assistance System) camera, rain light sensor, and the mounting provisions of the auto-dimming IRVM (Inner Rear View Mirror). This part is fixed on the windshield of an automobile using double-sided adhesive tapes and glue. ADAS, rain light sensors, and auto-dimming IRVM play an important part in the safety of the driver and everyone present in the automobile. This makes proper functioning of the integrated bracket very integral to occupant safety. Prior to this work, the following literature; Integrated Bracket for Rain Light Sensor/ADAS/Auto-Dimming IRVM with provision of mounting for Aesthetic Cover [1] outlines the design considerations and advantages of mounting several components on the same bracket. It follows the theme where the authors first define the components packaged on the integrated bracket and then the advantages of packaging multiple components on a single
Chandravanshi, PriyanshDharmatti, Girish
Triply Periodic Minimal Surface (TPMS) structures have gained significant attention in recent years due to their excellent mechanical properties, lightweight characteristics, and potential for energy absorption in various engineering applications, particularly in automotive safety. This study explores the design, manufacturing, and mechanical performance of both general and hybrid TPMS structures for energy absorption. Three types of fundamental TPMS unit cells—Primitive, Gyroid, and IWP—were modeled using implicit functions and combined to form hybrid structures. The hybrid designs were optimized by employing Sigmoid functions to achieve smooth transitions between different unit cells. The TPMS structures were fabricated using Selective Laser Melting (SLM) technology with 316L stainless steel and subjected to quasi-static compression tests. Numerical simulations were conducted using finite element methods to verify the experimental results. The findings indicate that hybrid TPMS
Liu, ZheWang, MingJieGuo, PengboLi, YouguangLian, YuehuiZhong, Gaoshuo
The rapid growth of electric vehicles (EVs) has led to a significant increase in vehicle mass due to the integration of large and heavy battery systems. This increase in mass has raised concerns about collision energy and the associated risks, particularly in high-speed impacts. As a consequence, crashworthiness evaluations, especially front-impact regulations, have become increasingly stringent. Crash speed between the vehicle and the Mobile Progressive Deformable Barrier (MPDB) is increasing, reflecting the growing emphasis on safety in the automotive industry. Moreover, a new frontal pole crash scenario is under consideration for future regulatory standards, highlighting the continuous evolution of crash testing protocols. To ensure occupant protection and battery safety, manufacturers have traditionally used Hot Blow Forming technology for producing closed-loop dash lower cross member components. However, this process is both costly and energy-intensive, necessitating more
Lee, JongminKim, DonghyunJang, MinhoKim, GeunhoSeongho, YooKim, Kyu-Rae
It is a well-known fact that a substantial part of the effort in the development of a semiconductor Intellectual Property (IP) goes into verification. Since the cost of incomplete or incorrect implementation increases exponentially in the later stages of the semiconductor supply chain, it is critical to identify, in early stages of development, a wide range of test cases that provides the assurance that the design achieves the functional specifications. This challenge is compounded for security as identifying verification scenarios for security specification and design decisions is complicated and often not approached methodically. The problem is further compounded by the fact that third-party IPs (3PIP) are generally developed following a standard specification of the relevant technology without complete knowledge of the environment or the application of the 3PIP. Such third-party IPs also carry the risk of trojans installed into them through supply chain. In this paper we discuss how
Ashrafi, GulamDunn, ChrisRoberts, Fred
Light Detection and Ranging (LiDAR) is a promising type of sensor for autonomous driving that utilizes laser technology to provide perceptions and accurate distance measurements of obstacles in the vehicle path. In recent years, there has also been a rise in the implementation of LiDARs in modern and autonomous vehicles to aid self-driving features. However, navigating adverse weather remains one of the biggest challenges in achieving Level 5 full autonomy due to sensor soiling, leading to performance degradation that can pose safety hazards. When driving in rain, raindrops impact the LiDAR sensor assembly and cause attenuation of signals when the light beams undergo reflections and refractions. Consequently, signal detectability, accuracy, and intensity are significantly affected. To date, limited studies have been able to perform objective evaluations of LiDAR performance, most of which faced limitations that hindered realistic, controllable, and repeatable testing. Therefore, this
Pao, Wing YiLi, LongAgelin-Chaab, MartinRoy, LangisKnutzen, JulianBaltazar, AlexisMuenker, KlausChakraborty, AnirbanKomar, John
The metal inert-gas (MIG) welding technique employed for aluminum alloy automotive bumpers involve a complex thermo-mechanical coupling process at elevated temperatures. Attaining a globally optimal set of model parameters continues to represent a pivotal objective in the pursuit of reliable constitutive models that can facilitate precise simulation of the welding process. In this study, a novel piecewise modified Johnson-Cook (MJ-C) constitutive model that incorporates the strain-temperature coupling has been proposed and developed. A quasi-static uniaxial tensile model of the specimen is constructed based on ABAQUS and its secondary development, with model parameters calibrated via the second-generation non-dominated sorting genetic algorithm (NSGA-II) method. A finite element simulation model for T-joint welding is subsequently established, upon which numerical simulation analyses of both the welding temperature field and post-welding deformation can be conducted. The results
Yi, XiaolongMeng, DejianGao, Yunkai
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