Browse Topic: Wear

Items (3,025)
Automobile emissions refer to the gases and particles released into the atmosphere by vehicles during their operation. These emissions contribute to environmental pollution and have an impact on human physiology and environment. This paper assimilates findings from a comprehensive research study examining tyre wear and its Indian perspective. Tyre wear understood as a factor affecting road safety, environmental health, and economic sustainability. The study identifies factors affecting tyre wear and provides overview regarding tyre wear generation in India, encompassing road infrastructure, vehicle characteristics, driving patterns, and environmental factors. Moreover, it examines the adverse effects of these particles on human health, such as respiratory ailments and cardiovascular diseases, as well as their impact on ecosystems. This paper delves measures to measure tyre wear and safeguard both environmental and public health. It also covers the tyre wear measurement methodologies to
Joshi, AmolKhairatkar, VyankateshBelavadi Venkataramaiah, Shamsundara
This technology solves a long-standing ergonomic and aesthetic problem in automotive and consumer interface design, as the use of mechanical switches disrupts the clean look of modern interiors and tends to attract dust and wear. Currently available technologies, such as capacitive touch buttons and mechanical push switches, do not provide the corresponding tactile feedback or clear indication of touch, and usually contain visible openings that interrupt the design flow. Moreover, traditional switches are made up of multiple built-in components, which results in complicated construction and difficult maintenance. To address these drawbacks, we propose a Seamlessly Integrated, Selectively Elevated Fabric Switch that remains flush with the surface when not in use and automatically rises to form a tactile interface when required. The system is a multi-layer construction consisting of an outer fabric upholstery layer, a tactile actuation membrane, and a smart electromagnetic actuator layer
Mohunta, SanjayPanchal, GirishPuthran, Shaunak
Today, passenger car makers around the world are striving to meet the increasing demand for fuel economy, high performance, and silent engines. Corporate Average Fuel Economy (CAFE) regulations implemented in India to improve the fuel efficiency of a manufacturer's fleet of vehicles. CAFE goal is to reduce fuel consumption and, by extension, the emissions that contribute to climate change. CNG (Compressed Natural Gas) engines offer several advantages that help manufacturers meet and exceed these standards. The demand for CNG vehicles has surged exponentially in recent years, CNG engine better Fuel efficiency and advantage in CAFÉ norms make good case for OEM & Customer to use more CNG vehicle. CNG is dry fuel compared to gasoline. These dry fuels lack lubricating properties, unlike conventional fuels like petrol, diesel and biofuels, which are wet and liquid. Consequently, the operations and failures associated with these fuels differ. The materials and designs of engine parts, such as
Poonia, SanjayKumar, ChandanSharma, ShailenderKhan, PrasenjitBhat, AnoopP, PrasathNeb, Ashish
Path planning is a key element of autonomous vehicle navigation, allowing vehicles to calculate feasible paths in challenging environments for applications like automated parking and low speed autonomous driving. Algorithms such as Hybrid A*, Reeds-Shepp, and Dubins paths are widely used and can generate collision-free paths but tend to create curvature discontinuities. These discontinuities result in sudden steering transitions, which create control instabilities, higher mechanical stress, and lower passenger comfort. To overcome these issues, this paper suggests a path-smoothing technique based on the pure-pursuit algorithm to produce smoothed curve paths appropriate for real-world driving. This method utilizes the practical approach of the original path, but removes sudden transitions that destabilize control. By ensuring smooth curvature, the vehicle undergoes fewer jerky steering actions, improved energy efficiency, less actuator wear, and improved high-speed tracking. This paper
S, ShriniyathiA, JosanaEdwin J, JoelT, AkshayaaM, Senthil VelKumar, Vimal
Compressed Natural Gas (CNG) offers a compelling alternative fuel solution due to its lower carbon emissions and cost-effectiveness compared to conventional gasoline. However, the dry combustion characteristics of CNG, coupled with higher combustion temperatures, often accelerate Exhaust valve face and Exhaust seat insert wear in internal combustion engines. Intake valve face and Intake seat insert are exposed to fresh air charge and temperature during engine operation remain with in limit and no issue reported in Intake valve side. This study addresses the critical challenge of premature exhaust valve wear in CNG applications by investigating the root cause and implementing improvements in the exhaust valve facing material, aiming to enhance durability and reliability for widespread CNG vehicle adoption. Exhaust valve face in CNG engine subjected to extreme condition leads to excessive valve face wear and cracking. To address these challenges, various technologies like hard material
Poonia, SanjayKumar, ChandanKundu, SoumenKumar, PrabhakarVats, RajeshKhan, PrasenjitSharma, Shailender
Overloading in vehicles, particularly trucks and city buses, poses a critical challenge in India, contributing to increased traffic accidents, economic losses, and infrastructural damage. This issue stems from excessive loads that compromise vehicle stability, reduce braking efficiency, accelerate tire wear, and heighten the risk of catastrophic failures. To address this, we propose an intelligent overloading control and warning system that integrates load-sensing technology with real-time corrective measures. The system employs precision load sensors (e.g., air below deflection monitoring via pressure sensors) to measure vehicle weight dynamically. When the load exceeds predefined thresholds, the system triggers a multi-stage response: 1 Visual/Audio Warning – Alerts the driver to take corrective action. 2 Braking Intervention – If ignored, the braking applied, immobilizing the vehicle until the load is reduced. Experimental validation involved ten iterative tests to map deflection-to
Raj, AmriteshPujari, SachinLondhe, MaheshShirke, SumeetShinde, Akshay
The adoption of sustainability in electric mobility has made it crucial to investigate environmentally friendly materials. Polymer materials used in automotive application plays very important role in material circularity contributing significant value addition to the overall carbon footprint index. This study discloses the development of recycled polyester textiles derived from PET bottle waste and use for automotive interior parts. The use of recycled textiles is directly helping the organization in scope 3 emissions to get the lower carbon footprint value as it is eliminating the use of fossil fuel resources in making the PET textiles. In this study, the development of 50% recycled PET textile and its feasibility for automotive interior is disclosed in detail. The 50 % recycled PET was tested against automotive critical requirements such as sun load UV resistance, abrasion durability, color migrations, soiling resistance, mechanical and thermal properties. The findings showed that
Palaniappan, ElavarasanVaratharajan, SenthilkumaranBalaji, K VDodiya, Rohanbhai
This study aims to investigate the influence of torque, rotational speed, lubricating oil temperature, and main bearing clearance on the vibration signals of diesel engine block surfaces, thereby establishing a foundation for diagnosing abnormal main bearing wear conditions using engine block surface vibration signals. An experimental test bench was constructed for a six-cylinder diesel engine to collect vibration signals under varying rotational speeds, torques, lubricant temperatures, and main bearing clearances. Frequency domain analysis and wavelet packet decomposition were then performed. The frequency domain analysis results indicate that the vibration signal amplitudes associated with abnormal main bearing wear are primarily concentrated below 5 kHz. Specifically, the energy in frequency bands below 1 kHz and around 2.5 kHz tends to increase with higher rotational speed, torque, and main bearing clearance, while the overall frequency domain amplitudes decrease with rising
Dong, YimingHu, YupingJi, ShaoboPan, ChiYue, YuanhangLiao, Guoliang
This study presents the design, construction, and experimental validation of a test bench for characterizing elastomer-based torsion suspensions in light vehicle applications. The system replaces conventional spring-damper assemblies with viscoelastic elements that simultaneously absorb and dissipate road-induced vibrations. We developed a scaled prototype instrumented with an Arduino-based data acquisition system and analyzed results using Octave®. The experimental protocol comprised: (1) tribological tests to identify optimal friction pairs through coefficient of friction (μ) and wear rate measurements, and (2) dynamometric evaluations of torque transmission capacity, power output, and efficiency across gear ratios (2.03-6.34). Results indicate that a steel-steel friction pair under a normal force of 250-300 N achieves optimal performance, delivering an output power of 1706 W (84.8% efficiency) and a torque of 30.25 Nm. Comparative analysis shows this configuration reduces wear rates
Silva, Diego BrunoGrandinetti, Francisco JoséCastro, Thais SantosDias, Érica XimenesSouza Soares, de Álvaro ManoelMartins, Marcelo SampaioReis de Faria Neto, dos Antônio
HmaxWVWmWR
Liu, YongTian, TaoHou, JianweiChen, GengWang, Anping
To delay the formation and development of local periodic fluctuations on the surface of rail structures and improve the durability of rail facilities, the dynamic response and wheel-rail interaction of rail structures were studied in depth based on frequency-modulated rail dampers (TRDs). A fully-coupled 3-D FE framework of the wheel–rail assembly, integrating frequency-modulated rail dampers (TRDs), was developed to quantify vibration energy dissipation. Simulated decay curves revealed a marked rise (> 50 %) in lateral damping efficiency within 600–1 000 Hz, confirming TRD’s targeted suppression of rail transverse motion. Then, the suppression effect of rail corrugation after TRD installation was tested, and the data collection was carried out in the test section to calculate the frequency of rail corrugation. It was found that the possibility of corrugation deterioration of the rail structure was greatly reduced after the installation of the rail damper, and the suppression effect of
Li, ChengshunLei, Zhenyu
Earthmoving machines are equipped with a variety of ground-engaging tools that are joined by bolted connections to improve serviceability. These tools are made from heat-treated materials to enhance their wear resistance. Attachments on earthmoving machines, including buckets, blades, rippers, augers, and grapples, are specifically designed for tasks such as digging, grading, lifting, and breaking. These attachments feature ground-engaging tools (GET), such as cutting bits or teeth, to protect the shovel and other earthmoving implements from wear. Torquing hardened plates of bolted joint components is essential to ensure uniform load distribution and prevent premature failure. Therefore, selecting the proper torque is an important parameter. This study focuses on analyzing various parameters that impact the final torque on the hardened surface, which will help to understand the torque required for specific joints. Several other parameters considered in this study include hardware
Parameswaran, Sankaran PottiBhosale, DhanajiKumar, Rajeev
The accurate prediction of road performance decay is of great significance for road maintenance and management. This paper takes the Xinjiang G577 highway as the research object, collects the measured data of the typical indexes of asphalt pavement since the past years (Deterioration Condition Index (PCI), Technical Condition Index (PQI)), and studies its decay. The model is constructed on the basis of time series1, and the exponential decay model of asphalt road PQI and PCI is derived. The model’s accuracy is then tested by calculating the correlation coefficient, mean absolute error (MAE), and other accuracy tests. The results demonstrate that the model exhibits a high degree of fit.
Tian, WeiBai, HaotianWang, TaiweiWang, JiayanDai, Xiaomin
The height valve adjusting rod is an important part of the suspension system, used to adjust the height of the train to adapt to the train through the curve, slope or uneven track when the height valve adjusting rod fracture failure, the train’s suspension system can not be adjusted normally, may lead to the height of the train is too high or too low, affecting the stability of the train and the driving safety. In this paper, an underground vehicle height valve adjusting rod fracture failure of the problem was studied and analysed, the specific conclusions are as follows: height valve adjusting rod there are two main vibration frequency, 60Hz and 340Hz, 60Hz main frequency has always existed, and 340Hz vibration frequency are present in part of the interval, but also caused by the vehicle vibration of the main reason for the local larger; height valve adjusting rod stress there is also a significant vibration The main frequency of 340Hz, similar to the vibration characteristics of the
Wang, ChaoYang, ChenPan, Minkai
Urban road traffic state classification is essential for identifying early-stage deterioration and enabling proactive traffic management. This study presents a novel method to accurately assess the traffic state of urban roads while addressing the limitations of existing methods in spatial generalization performance. The approach consists of three key components. First, several indicators are designed to capture the spatial-temporal evolution mechanisms of traffic state, speed freedom, flow saturation, and their variations over time and space. Then, a feature learning module based on an AutoEncoder network is introduced to reduce the dimensionality of the constructed feature set. This enhances feature distinction while mitigating noise effects on classification results. Third, k-means clustering is applied to analyze significant features extracted from the AutoEncoder latent space, categorizing road traffic states into fluent, basic fluent, moderate congested and severe congested
Wang, XiaocongHuang, MinGuo, XinlingXie, JieminZhang, Xiaolan
Designing the gear shift control for an automotive transmission is a complex task because it involves handling nonlinear behaviors like changes in friction between clutch plates and fluctuations in oil temperature. While deep reinforcement learning (DRL) has recently been used to reduce shift shock, most existing methods don’t account for real-world changes such as transmission aging. One major issue that becomes worse with aging is clutch judder—a type of vibration caused by wear. Traditional reinforcement learning assumes that the environment stays the same, which can lead to unstable learning when conditions change, making it hard to consistently reduce shift shock. To address this, we propose a new algorithm that adapts to aging transmissions by adjusting the discount factor—a key parameter in reinforcement learning that balances short-term and long-term rewards. Instead of keeping this factor fixed, our method starts with a lower value to ensure stable learning and gradually
Ogawa, KazukiAihara, TatsuhitoGoto, TakeruMinorikawa, Gaku
Vehicle behavior is strongly influenced by tire performance, as tires serve as the primary interface between the vehicle and the road surface. Since identical vehicles equipped with different tire sets—or even the same tires operating under varying thermal and wear conditions—can exhibit significantly different handling characteristics, this study aims to quantify their impact on both steady-state and transient cornering responses through a dedicated evaluation methodology. To demonstrate the generalization of the proposed approach, three completely different validated vehicle digital twins—a passenger car, a sports car, and a formula car—are analyzed in a virtual environment, employing Vi-Car Real Time for vehicle and scenario representations, and RIDEsuite for tire modeling, considering thermal and wear effects. The simulations were designed using a structured design of experiments approach, resulting in 15 predefined combinations of tire temperature and wear states. Results show
Aratri, RobertoRomagnuolo, FabioDe Pinto, StefanoFarroni, FlavioDe Bellis, SergioBottiglione, FrancescoMantriota, GiacomoSakhnevych, Aleksandr
The effects of particle size and composition of platelet titanates, including potassium titanate and potassium-magnesium titanate, were investigated to determine their friction stability, wear resistance, and transfer film formation. The composition and properties of titanates were characterized using X-ray diffraction (XRD), X-ray fluorescence (XRF), and particle size analysis. Tribological properties were evaluated using a tribometer (MFT-5000), while the worn surfaces were analyzed with scanning electron microscopy (SEM) and energy-dispersive spectroscopy (EDS). Results indicate that the transfer film characteristics are significantly influenced by the particle size and composition of platelet titanates. Brake pads containing potassium-magnesium titanates formed a more uniform transfer film, leading to improved friction stability and reduced wear rates. In contrast, potassium titanates increased friction levels but also resulted in higher wear on the brake friction materials. These
Jara, Diego ChavezLorenzana, CarlosSliepcevich, 1Lt AndreaConforti, Michael
The effective reduction of particulate emissions from modern vehicles has shifted the focus toward emissions from tire wear, brake wear, road surface wear, and re-suspended particulate emissions. To meet future EU air quality standards and even stricter WHO targets for PM2.5, a reduction in non-exhaust particulate (NEP) emissions seems to be essential. For this reason, the EURO 7 emissions regulation contains limits for PM and PN emissions from brakes and tire abrasion. Graz University of Technology develops test methods, simulation tools and evaluates technologies for the reduction of brake wear particles and is involved in and leads several international research projects on this topic. The results are applied in emission models such as HBEFA (Handbook on Emission Factors). In this paper, we present our brake emission simulation approach, which calculates the power at the wheels and mechanical brakes, as well as corresponding rotational speeds for vehicles using longitudinal dynamics
Landl, LukasKetan, EnisHausberger, StefanDippold, Martin
Advanced ferritic nitrocarburizing process combined with a specialized post-oxidation treatment described as FNC + Smart ONC® [1] is developed for brake rotor applications. The process can be applied to standard grey cast iron brake rotors, significantly reducing PM 10 emissions to levels below the Euro 7 limits for most vehicles equipped with at least some recuperative braking capabilities, all without compromising performance. Finished grey iron brake rotors, ferritic nitrocarburized and post oxidized were evaluated according to several industry standards. The standards include SAE J2707B (Block Wear Test including Highway) [2], GRPE-90-24 Rev.1 Emission Test (Full WLTP Brake Cycle 6 Times) [3], and SAE J2522 (AK-Master Performance) [4]. Nitrocarburized post oxidized brake rotors were compared to untreated grey iron rotors exposed to several friction materials. Ferritic nitrocarburizing and post oxidation addresses the issue of corrosion, which is particularly relevant for brake
Winter, Karl-MichaelHolly, Mike
With the introduction of the Euro 7 regulation, non-exhaust emissions – particularly those arising from brake and tire abrasion – will be regulated and subject to emission limits for the first time. This presents significant challenges not only for OEMs striving to meet these targets within the given timeframe, but also for suppliers, who must develop innovative solutions for the precise measurement, analysis, and mitigation of these emissions. To address this, it is essential to establish and industrialize new testing methodologies as structured, scalable, and cost-efficient processes. Beyond pure measurement capability, service providers in this domain are increasingly expected to serve as feedback mechanisms – identifying process limitations, proposing targeted improvements, and thereby enabling continuous development in line with evolving technical and regulatory requirements. In this context, AVL is pursuing a holistic development strategy that integrates brake emission
Grojer, Bernd
As Lowmet pad porosity increases, pad hardness decreases; pad ISO compressibility increases; the nominal friction coefficient increases (SAE J2522); and the disc wear/pad wear decreases. Brake squeal occurrence is affected by the total wear of disc and pads; the wear differential between the inboard pad and outboard pad; pad tangential taper; and pad hardness/material damping. Also, pad chamfer shape has a strong influence on brake squeal occurrence.
Rhee, Seong KwanRathee, AmanSingh, Shiv RajSharma, Devendra
Tire wear is a significant source of microplastics and airborne particulate matter, contributing to environmental pollution and posing health risks. This study aims to develop a reliable method for quantifying tire wear and TWP on an outer drum test bed while achieving realistic wear rates. A degumming method using talcum powder was applied to prevent tire adhesion, which significantly increased wear rates but introduced complications in particle measurements. To address this, a flow-optimized enclosure was implemented to minimize background emissions. Particle emissions were quantified using APCs, PM samplers, and an ELPI+. The results underscore the challenge of distinguishing between TWP and talcum powder contributions. To estimate the percentage of airborne particle mass, a novel method was employed that calculates the RGB values of images of PM filters. This method estimates the blackening of the filter to determine the amount of TWP present. Size distribution analysis revealed
Schubert, LudwigArias Torres, María AlejandraBigl, StephanSteiner, GeraldHuber, MichaelLex, Cornelia
Brake wear emissions are a significant contributor to particle mass (PM) emissions originating from road transport. In Europe, this is taken into consideration by including emission limits for brake wear particles in the legislation. UN GTR (United Nations Global Technical Regulation) No.24 is a technical description of how to measure the particle number (PN) and PM emissions of brakes. PN measurement includes solid particle number (SPN) and total particle number (TPN), meaning excluding and including the volatile particle matter, respectively. In this study, we examine over 500 TPN and SPN emission factors, in terms of SPN-TPN ratio. To interpret the emission factor data, we present results of a characterization of SPN and TPN measurement instruments in a laboratory setting. We discuss the benefits of using a flow splitter in the PN measurement and present an experimental demonstration of its suitability for measurement of brake wear PN. Combining the results of this investigation
Martikainen, SampsaPramstrahler, MadlenWeidinger, ChristophRainer, AndreasEngler, DieterHuber, Michael
This SAE Recommended Practice is intended to give information to engineers and designers in order that access to a passenger handgrip, when used, is easily obtained, and that such handgrips offer maximum safety for a person at least as large as a 95th percentile adult male during snowmobile operation.
Snowmobile Technical Committee
What if the clothes you wear could care for your health? MIT researchers have developed an autonomous programmable computer in the form of an elastic fiber, which could monitor health conditions and physical activity, alerting the wearer to potential health risks in real time. Clothing containing the fiber computer was comfortable and machine washable, and the fibers were nearly imperceptible to the wearer, the researchers report.
Artemis III will mark humanity’s first return to the lunar surface since 1972. Astronauts returning to the Moon as part of the Artemis III mission, currently planned for 2027, will wear a next-generation spacesuit that will allow astronauts to walk on the Moon for the first time in over 50 years.
When a train passes continuously over a section of the track, the track gradually moves away from the intended vertical and horizontal alignment with time and repeated use. Regular maintenance on the track, such as leveling, lifting, lining, and tamping, is necessary to maintain the optimal geometry of the track. Ballast is leveled and squeezed by hydraulic rams in tamping machines. The tamping is a process of ballast packing under railway tracks. In current system a set of tungsten carbide chips are attached either by welding or by coating on tamping tool tip made of EN24 steels. These tungsten carbide chips directly come in contact with the ballasts. After few tamping works, gradually these chips torn out and need to be replaced after certain period. Tungsten carbide is a costly material, therefore this research deals with replacement of tungsten carbide with silicon carbide (easily available cheaper) coating used for tamping tools tip. The study consists of microstructural
Mishra, MamtaPandey, ManasSingh, ShrutiSrivastava, SanjayKumar, Jitendra
In electrified drivetrains, lubricants are commonly in contact with the motor and other electrical components as well as the gears and bearings. Copper, present in these electrical components, is susceptible to corrosion by fluids containing active sulfur, which can lead to catastrophic failure of the unit. Lubricating fluids for electric vehicles (referred to as e-fluids) must not cause corrosion and must maintain high performance while having suitable electrical conductivity, material compatibility, and heat transfer properties. We describe a new formulation without active sulfur that has recently entered the market, which can protect against copper corrosion. We show that this e-fluid can provide suitable wear protection under field trial conditions, and that the e-fluid provides improved wear protection in bearing (FE-8) tests compared to a traditional extreme pressure axle fluid (API GL-4). Surface analysis (X-ray photoelectron spectroscopy) measurements of the component surfaces
Hopper, Elizabeth R.Williams, Megan S.Gahagan, Michael
In response to the evolving landscape of exhaust gas regulations for small powertrains, reducing NOx emission is increasingly important. This study deeply investigated the feasibility of a NOx storage catalyst (NSC) containing cerium oxide (CeO2) and barium oxide (BaO) for reducing NOx emission. The key functions, NOx storage and reduction performances were evaluated, and deterioration mechanisms were explored through performance evaluations and physical property analyses. The findings revealed a strong correlation between the size of CeO2 crystals and NOx storage performance at low temperature, such as those encountered during city driving conditions. Conversely, at high temperature, such as those during highway driving conditions, NOx storage performance correlated well with sulfur deposition, suggesting that the formation of barium sulfate (BaSO4) contributes to the deactivation. This experiment also showed a strong correlation between NOx reduction performance and BaSO4 formation
Nakano, FumiyaKoito, Yusuke
The use of plastic gears has expanded due to their lightweight properties, low noise emission, and cost-effective manufacturing. For instance, in the transportation equipment industry, some metal gears are being replaced with plastic gears. To achieve further size and weight reduction, gears must be able to withstand higher loads without damage. Gears have various modes of damage. Since there are different types of wear, each with different factors, it is important to identify the factors and take appropriate countermeasures. In gear meshing, there are many factors that affect wear, so restricted-factor tests are required to confirm the effectiveness of countermeasures. The purpose of this study is to elucidate the wear regime in high-load gear meshing and then to establish a simplified evaluation method replicating the meshing of gears for wear resistance focusing on the relative sliding between the two surfaces of metal and plastic. In the evaluation, changes in wear morphology over
Yamamoto, JimpeiSuzuki, TakaharuAko, NatsukiIwasaki, ShinyaKurita, Hirotaka
This article analyses the fundamental curving mechanics in the context of conditions of perfect steering off-flanging and on-flanging. Then conventional, radial, and asymmetric suspension bogie frame models are presented, and expressions of overall bending stiffness kb and overall shear stiffness ks of each model are derived to formulate the uniform equations of motion on a tangent and circular track. A 4 degree of freedom steady-state curving model is formulated, and performance indices such as stability, curving, and several parameters including angle of attack, tread wear index, and off-flanging performance are investigated for different bogie frame configurations. The compatibility between stability and curving is analyzed concerning those configurations and compared. The critical parameters influencing hunting stability and curving ability are evaluated, and a trade-off between them is analyzed. For the verification, the damped natural frequencies and mean square acceleration
Sharma, Rakesh ChandmalSharma, Sunil KumarPalli, SrihariRallabandi, Sivasankara RajuSharma, Neeraj
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
Topology reasoning plays a crucial role in understanding complex driving scenarios and facilitating downstream planning, yet the process of perception is inevitably affected by weather, traffic obstacles and worn lane markings on road surface. Combine pre-produced High-definition maps (HDMaps), and other type of map information to the perception network can effectively enhance perception robustness, but this on-line fused information often requires a real-time connection to website servers. We are exploring the possibility to compress the information of offline maps into a network model and integrate it with the existing perception model. We designed a topology prediction module based on graph attention neural network and an information fusion module based on ensemble learning. The module, which was pre-trained on offline high-precision map data, when used online, inputs the structured road element information output by the existing perception module to output the road topology, and
Kuang, QuanyuRui, ZhangZhang, SongYixuan, Gao
With the increasing clarity of the CNVII emission legislation, it is foreseeable that CNVII will further tighten the emission limits of major pollutants such as Nitrogen Oxide (NOx), Nitrous Oxide (N2O) and Particulate Number (PN). Together with the implementation of stage IV fuel consumption legislation in July 2025, which requires engine fuel consumption reduction or thermal efficiency improvement, it will lead to further deterioration of its pollutant emissions and reduction of exhaust temperature, posing greater challenges to the After-Treatment System (ATS) in terms of NOx removal, particularly during engine cold start and N2O formation suppression. This study is an extension of our earlier investigation [1], and a novel copper-based corrugated SCR (Full Body-CuSCR, FB-CuSCR) technology was successfully applied. The results based on a modified CNVI medium duty engine indicated excellent dynamic response of the FB-CuSCR technology over cordierite which helped to improve the
Wang, YanFu, GuangxiaChen, ShuyueAberg, AndreasJiang, ShuiyanZhang, Jun
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
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
Two 50-hr engine dynamometer tests were conducted on 12-cylinder diesel military engines with differing piston ring sets. Engine A exhibited more than double the oil consumption over engine B. An investigation was conducted to explain why the oil consumption differed by employing several posttest analytical techniques including cylinder bore geometry measurements, surface metrology, wear characterization, and chemical analysis on the piston rings and cylinder wall coatings. The 3D colormaps of cylinder bore deformation showed uneven volumetric deformation through the piston stroke instead of 2D plane deformation. It was found that the primary reason of high oil consumption was direct loss of sealing between the piston, piston ring and cylinder bore due to predominately abrasive wear, three-body abrasive wear and bore polishing. Furthermore, the compromised sealing of the combustion chamber led to blow-by. Carbon deposits, corrosive byproducts, surface abrasives, loss of desired surface
Thrush, StevenChen, AijieFoley, MichaelSebeck, KatherineBoufakhreddine, Ziad
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
What if the clothes you wear could care for your health?
The chemical milling process used in the aerospace industry generates substantial metallic residue in the etching bath, referred to as chemical milling sludge (CMS). The direct disposal of CMS into the environment leads to ecological deterioration and economic losses. This study focused on the recovery of aluminum from the aerospace industry CMS, aiming to mitigate environmental harm and enhance resource efficiency. The energy-dispersive X-ray (EDX) analysis revealed that the aluminum content in extracted CMS increased significantly to 95.86%, compared to 28.98% in non-extracted sludge. The XRD analysis of the CMS extracted samples also revealed the presence of increased Al2O3. The surface morphology study suggested the irregularly shaped particles with large chunks, and fine granules were observed on CMS. The yield of Al2O3 was observed to be 35.9% (wt) prior to the calcination process followed by 12.1% (wt) after calcination. The phytotoxicity study indicated that the CMS inhibited
Prasad, JagSonwani, Ravi Kumar
Items per page:
1 – 50 of 3025