Automotive Engineering Research Articles

Data Disparity and Temporal Unavailability Aware Asynchronous Federated Learning for Predictive Maintenance on Transportation Fleets

Predictive maintenance has emerged as a critical application in modern transportation, leveraging sensor data to forecast potential damages proactively using machine learning. However, privacy concerns limit data sharing, making Federated learning an appealing approach to preserve data privacy. Nevertheless, challenges arise due to disparities in data distribution and temporal unavailability caused by individual usage patterns in transportation. In this paper, we present a novel asynchronous federated learning approach to address system heterogeneity and facilitate machine learning for predictive maintenance on transportation fleets. The approach introduces a novel data disparity aware aggregation scheme and a federated early stopping method for training. To validate the effectiveness of our approach, we evaluate it on two independent real-world datasets from the transportation domain: 1) oil dilution prediction of car combustion engines and 2) remaining lifetime prediction of plane turbofan engines. Our experiments show that we reliably outperform five state-of-the-art baselines, including federated and classical machine learning models. Moreover, we show that our approach generalises to various prediction model architectures.

Surface defect detection of cylinder liner based on improved YOLOv5

Cylinder liner is an internal part of the automobile engine, which plays an important role in the automobile internal combustion engine. Therefore, it is a top priority to accurately and quickly detect the cylinder liner surface defects. In order to effectively achieve the classification and localization of surface defects on the cylinder liner, this paper establishes a dataset for surface defects on cylinder liner and proposes a based on improved YOLOv5 algorithm for detecting surface defects on cylinder liner. Firstly, a machine vision system is established to acquire on-site images and perform manual annotation to build the dataset of surface defects on cylinder liner. Secondly, the GSConv SlimNeck mechanism is introduced to reduce the model complexity; the Bi-directional Feature Pyramid Network (BiFPN) is used to fuse the feature information at different scales to enhance the detection accuracy of small surface defects on cylinder liner; and embedding the SimAM attention mechanism to focus on the object region of interest and improve the accuracy and robustness of the model. The final improved YOLOv5 model reduces the number of model parameters by 15.8% compared to the non-improved YOLOv5. And the experimental results on our self-built dataset for cylinder liner defects show that the mAP0.5 is improved by 0.4%. This means that the accuracy of model detection was not compromised. This method can be applied to actual production processes.

Cr-rich structure evolution and enhanced mechanical properties of CoCrFeNi high entropy alloys by mechanical alloying

Mechanically-alloyed CoCrFeNi high entropy alloys (MA-HEAs) show better mechanical properties than as-cast HEAs. However, the limited amount of powder milled in one-milling cycle creates a challenge in larger-scale applications. The low ball-to-powder ratio (BPR) milling used to increase powder yield resulted in the formation of Cr-rich second phases in the face-centered cubic matrix. To overcome the above issues, in this work, with a low BPR of 5:1, four different processes were analyzed: quicker milling intervals, higher milling speed, and the pre-alloying of Cr and Ni. All parameters mentioned before were used and tested together in the fourth sample. Samples were consolidated by spark plasma sintering technique. Microstructural characterization was made on a Scanning Electron Microscope equipped with EDS and EBSD detectors and a Transmission Electron Microscope. X-ray diffraction was employed to develop the structural evolution of powders sintered and annealed samples. The global hardness was measured using microhardness tests, while the nanohardness tests helped us correlate the evolution of secondary phases with their mechanical properties. The results show that pre-alloying elements with the lowest diffusion coefficient before the main milling process might be an attractive strategy to improve productivity and optimize microstructure without limiting the efficiency of low BPR MA-HEAs. The results described below demonstrate the promising perspective for the implementation of powder metallurgy techniques in a mass scale production as low BPR is essential for numerous applications like aerospace industry, car engines and medicine, where improved productivity of powder mixing is mandatory.

Catalytic NO<sub>x</sub> Aftertreatment—Towards Ultra-Low NO<sub>x</sub> Mobility

Article Catalytic NOx Aftertreatment—Towards Ultra-Low NOx Mobility Navjot Sandhu * , Xiao Yu, and Ming Zheng Department of Mechanical, Automotive and Materials Engineering, University of Windsor, 401 Sunset Avenue, Windsor, ON N9B 3P4, Canada * Correspondence: sandh12p@uwindsor.ca Received: 26 January 2024 Accepted: 13 March 2024 Published: 20 March 2024 Abstract: The push for environmental protection and sustainability has led to strict emission regulations for automotive manufacturers as evident in EURO VII and EPA2027 requirements. The challenge lies in maintaining fuel efficiency and simultaneously reducing the carbon footprint while meeting future emission regulations. Nitrogen oxides represent one of the major and most regulated components of automotive emissions. The need to meet the stringent requirements regarding NOx emissions in both SI and CI engines has led to the development of a range of in-cylinder strategies and after-treatment techniques. In-cylinder NOx control strategies including charge dilution (fresh air and EGR), low-temperature combustion, and use of alternative fuels (as drop-in replacements or dual fuel operation) have proven to be highly effective in thermal NOx abatement. Aftertreatment methods are required to further reduce NOx emissions. Current catalytic aftertreatment systems for NOx mitigation in SI and CI engines include the three-way catalyst (TWC), selective catalytic reduction (SCR) and lean NOx trap (LNT). This review summarizes various approaches to NOx abatement in IC engines using aftertreatment catalysts. The mechanism, composition, operation parameters and recent advances in each after-treatment system are discussed in detail. The challenges to the current after-treatment scenario, such as cold start light off, catalyst poisoning and the limits of current aftertreatment solutions in relevance to the EURO VII and 2026 EPA requirements are highlighted. Lastly, recommendations are made for future aftertreatment systems to achieve ultra-low NOx emissions.

Review of the Integration of Hybrid Electric Turbochargers for Mass-Produced Road Vehicles

This study presents the findings of a comprehensive SWOT analysis on the integration of hybrid electric turbochargers (HETs) in mass-produced road vehicles. Through a synthesis of multiple research findings, this study compared the performance of HETs on thermal engines versus traditional turbochargers and HETs on thermal engines versus HETs on hybrid engines. The analysis highlights key strengths, weaknesses, opportunities, and threats associated with the adoption of HET technology in the automotive industry. The results of the SWOT analysis provide valuable insights for both manufacturers and consumers regarding the feasibility and benefits of adopting HET technology in modern vehicles. By elucidating the fundamental mechanics of turbochargers and demonstrating the potential of hybrid electric turbocharging, this study contributes to a deeper understanding of the role of HETs in shaping the future of automotive engineering. In conclusion, this study underscores the potential of HETs to substantially mitigate the environmental impact of the transportation sector by reducing emissions and conserving energy. The novelty of this study is reflected in its comprehensive synthesis of multiple research findings, offering insights into the feasibility and benefits of adopting HET technology in modern vehicles, thereby contributing to a deeper understanding of the role of HETs in shaping the future of automotive engineering and highlighting their continued significance, as evidenced by the systematic SWOT analysis presented. Their ability to optimize fuel efficiency and power output, coupled with the feasibility of downsized engines, positions HETs as an attractive option for sustainable mobility solutions. Further research is warranted to comprehensively understand the environmental and economic implications of widespread HET adoption.

Fault diagnosis and identification of rotating machinery based on one-dimensional convolutional neural network

The paper focuses on two kinds of rotating machinery, miniature table drilling machine and automobile engine, as the research object. Traditional machine learning has the need for manual feature extraction, and is very dependent on expert diagnostic experience and expertise, but also has the disadvantages of low accuracy, low timeliness, low efficiency, etc. For the traditional rotating machinery fault diagnosis method is more based on the traditional machine learning model, this paper puts forward a one-dimensional convolutional neural network-based fault identification method. According to the characteristics of the miniature table drilling machine and the automobile engine which are not detachable, the corresponding faults are set up respectively, Vibration signals of the attitude sensor are obtained by using the signal collector, and the collected data are preprocessed, then the CNN model is built for fault identification, and the network structure is constantly optimized to obtain the optimal network model with high accuracy (up to 100 %) and robustness. The results show that the one-dimensional convolutional neural network model improves the fault recognition accuracy and reduces the cost compared with the traditional machine learning SVM model when the original signal is used as the input signal.

Design of the Steering Feedback Controller of a Steer-by-Wire System Using Admittance Model

The steer-by-wire (SbW) system is a promising system in the realm of automotive engineering. It substitutes the mechanical connection between the steering wheel and the front road wheels with an electronic signal-based functional connection. The SbW system offers several advantages over conventional steering systems, including weight reduction, reduced vibration, and enhanced steering functionality configuration. However, the absence of a mechanical linkage in the SbW system gives rise to certain challenges. The SbW system requires endowing adequate steering feel such as damping and reaction force using feedback motor, and the road wheel needs robust control of pinion motor for normal load variation by passengers and self-aligning torque as external disturbance. The SbW system is composed of the steering feedback module (SFM) and the road wheel module (RWM). This paper proposes a control approach to generate steering feel for SFM, in which steering feel is generated using an admittance model based on velocity control. A disturbance observer is applied to ensure robustness of velocity control. The steering wheel torque versus steering wheel angle (T–A) curve is used to analyze steering feel characteristic and evaluate steering feel. The proposed steering system is validated through experiments that confirm its ability to provide satisfactory steering feel for vehicles. This work may offer a novel solution for the design of advanced steering systems in the field for the future mobility such as an autonomous driving.

A Review on the Impact of Bio-Additives on Tribological Behavior of Diesel Fuels

Automobile engines require lubrication to lessen the impact of friction due to the high levels of wear and frictional heat generated by the sliding parts. Wear and friction will cause engine parts to endure for less time, be less reliable, and require more maintenance. Diesel fuel can potentially be replaced with biodiesel among other fuels. Diesel engines have a serious problem with equipment that is lubricated by the fuel itself. This study’s goal is to assess the influence of bio-additives on the diesel fuel tribological behavior and energy balance during the car’s idle running, acceleration, constant speed, and braking. Lubricity issues with reformulated diesel and lubricity test procedures are explained. The relationship between tribology and bio-additives is also briefly illustrated. According to the literature, adding bio-additives to fuel boosts its lubricity. Biodiesel has long been considered an additive with excellent lubricant properties. Even in small amounts, adding biodiesel to diesel fuel can increase its lubricity without the need for conventional lubricity additives. This is especially true for diesel fuel with ultralow sulfur. Diesel fuel characteristics determine the precise blending percentage needed to provide the proper lubricity of maximum 520 μm testing wear scars with a high-frequency reciprocating rig (HFRR), although 2% biodiesel nearly invariably imparts adequate lubricity to biodiesel blends. Tall oil fatty acid (TOFA) was one of the bio-additives investigated by HFRR. When the additive concentration was raised from 0 to 500 g/g, the wear scar diameter (WSD) of nonadditive diesel fuel was lowered by 60.3%, from 630 to 250 μm, and the coefficient of friction (COF) was lowered by 95.7%, from 0.47 to 0.02.

How Drivers Lose Control of the Car

<div>After a severe lane change, a wind gust, or another disturbance, the driver might be unable to recover the intended motion. Even though this fact is known by any driver, the scientific investigation and testing on this phenomenon is just at its very beginning, as a literature review, focusing on SAE Mobilus<sup>®</sup> database, reveals. We have used different mathematical models of car and driver for the basic description of car motion after a disturbance. Theoretical topics such as nonlinear dynamics, bifurcations, and global stability analysis had to be tackled. Since accurate mathematical models of drivers are still unavailable, a couple of driving simulators have been used to assess human driving action. Classic unstable motions such as Hopf bifurcations were found. Such bifurcations seem almost disregarded by automotive engineers, but they are very well-known by mathematicians. Other classic unstable motions that have been found are “unstable limit cycles.” The driving simulator results have been reproduced by experimental tests on track. We have assessed that the driver’s steering action can make the car motion unstable if a proper disturbance has acted. The delay of the driver’s steering action is the primary cause for the generation of limit cycles. Future automated vehicles should be conceived by focusing on the addressed phenomenon.</div>

Influence of Quenching and Tempering on the Tribological and Corrosion Behavior of Plasma‐Nitrided Society of Automotive Engineers 52100

Society of automotive engineers (SAE) 52100 (100Cr6) steel, used in manufacturing bearings and shafts, deserves attention due to wear and corrosion problems that cause machine losses in the industry. To solve these problems, heat treatments such as quenching and tempering are adopted to reduce wear mechanisms. However, in this work, the effect of these previous heat treatments on the final properties of plasma nitrided steel at three different temperatures (400, 450, and 500 °C) is evaluated. Surface hardness, tribological behavior, and corrosion resistance are evaluated. In the results of Vickers hardness, wear, and electrochemical analysis, it is shown that performing plasma nitriding at 400 and 450 °C on previously heat‐treated SAE 52100 steel provides better mechanical resistance and chemical integrity in a corrosive environment, making the studied steel more comprehensive for important industrial applications.

Preface

The ESFA Congress is a part of a series of SIAR (Society of Automotive Engineers from Romania) congresses which are organized annually, by rotation, in Romanian universities that train engineers in the field of Automotive Engineering (Bucharest, Brașov, Pitesti, Craiova, Cluj, Chisinau, Timișoara). This congress is the 33rd edition of the SIAR Congress.The ESFA Congress are hosted by National University of Science and Technology POLITEHNICA Bucharest, the oldest and most prestigious engineer school from Romania. These congresses are organized by the Automotive Engineering Department since 1981, being one of the scientific events with great visibility among specialists in the field of Automotive Engineering.According to the organizers’ expectations, more than 150 Romanian specialists and from other countries, renowned companies involved in various activities specific to the field of automotive engineering, participated in this congress.The Congress provided optimal conditions for the presentation of the latest achievements of scientific and technological research in the automotive industry and automotive components, in the field of vehicle maintenance and road transport, and facilitated the exchange of information and experience between participants.One of the main purposes of the congress was to promote and present the most modern products and current technologies in the field of automotive engineering from the most prestigious romanian companies and abroad. For this purpose, exhibitions (indoor and outdoor), demonstrations, experimental tests, appropriate software presentations etc. were organized within the congress.On the occasion of the SIAR congress, the final stage of the Student Competition in Automotive Engineering “Prof. university Eng. Constantin GHIULAI” is organized annually by SIAR, with two sections: Vehicle Dynamics (nineth edition) and Automotive CAD - CATIA (sixth edition).About of 70 students from almost all Romanian university centers which have studied programs in the field of Automotive Engineering participated in the final stage of this competition.ESFA 2023 Proceedings EditorsList of Honorary Committee, Scientific and Technical Committee, Congress Management, Organizing Committee, Brief overview of ESFA 2023 Congress, Oral presentations of scientific papers by sections, Exhibition, Aknowledgements are available in this pdf.

A Study on Emergence of Clutch Graphs from Cycle Graphs: A Comprehensive Analysis

The clutch is one of the substantial devices for constructing vehicles in automobile engineering. In terms of network toughness against failures or disruptions, the clutch-based graph can be used to model insufficiency of primary pathways and the availability of alternative routes in communication networks. In this paper, the identification of the clutch graph Cl3n(G) from the cycle graph Cn(G) has been proposed. A clutch graph Cl3n(G) generating from a cycle graph with 3n vertices and 4n edges (n ≥ 4 and even). The notions of degree, girth, and chromatic number of the clutch graph have been discussed. Further, the existence of the bipartite and Hamiltonian graphs on the clutch graph has been examined.

Prenatal diesel exhaust exposure alters hippocampal synaptic plasticity in offspring.

Diesel exhaust particles (DEPs) are major air pollutants emitted from automobile engines. Prenatal exposure to DEPs has been linked to neurodevelopmental and neurodegenerative diseases associated with aging. However, the specific mechanism by DEPs impair the hippocampal synaptic plasticity in the offspring remains unclear. Pregnant C57BL/6 mice were administered DEPs solution via the tail vein every other day for a total of 10 injections, then the male offsprings were studied to assess learning and memory by the Morris water maze. Additionally, protein expression in the hippocampus, including CPEB3, NMDAR (NR1, NR2A, NR2B), PKA, SYP, PSD95, and p-CREB was analyzed using Western blotting and immunohistochemistry. The alterations in the histomorphology of the hippocampus were observed in male offspring on postnatal day 7 following prenatal exposure to DEPs. Furthermore, 8-week-old male offspring exposed to DEPs during prenatal development exhibited impairments in the Morris water maze test, indicating deficits in learning and memory. Mechanistically, the findings from our study indicate that exposure to DEPs during pregnancy may alter the expression of CPEB3, SYP, PSD95, NMDAR (NR1, NR2A, and NR2B), PKA, and p-CREB in the hippocampus of both immature and mature male offspring. The results offer evidence for the role of the NMDAR/PKA/CREB and CPEB3 signaling pathway in mediating the learning and memory toxicity of DEPs in male offspring mice. The alterations in signaling pathways may contribute to the observed damage to synaptic structure and transmission function plasticity caused by DEPs. The findings hold potential for informing future safety assessments of DEPs.

A Duster Plug-in Hybrid Electric Vehicle with Wireless Charging System

The paper presents the GASTER Electricway 4WD concept, Plug-in Hybrid Electric Vehicle (PHEV) type, in development within the Automotive Engineering Research Centre of the University of Pitesti, aiming to create a green and versatile version of Romanian Dacia Duster. The car has been built by implementing a hybrid propulsion system with electrified rear axle. This hybrid system is PHEV, parallel type with two shafts, organized in a motorized solution E4WD (Electricway 4WD). It is composed of a thermal power train with a 1.6 litre engine fuelled with Compressed Natural Gas (CNG) and a CVT (Continuously Variable Transmission), placed in the front of the vehicle. The electric powertrain, located at the rear side of the vehicle includes an electric motor coupled with a mechanical transmission. The traction battery is Lithium-ion NMC type. The charging of the traction battery can be performed with the on board charger of by cable from a Wallbox or public station, in the Standard version, and Plug-in bidirectional or Wireless from renewable sources in the Premium version.

Enhancing oil pressure dynamics in a high-performance racing engine with innovative lubrication system tuning

This work focuses on fine-tuning the oil pressure dynamics of a single-seater formula car, a participant in international engineering competition organized by the Society of Automotive Engineers (SAE). Adhering to competition guidelines, the Honda CBR600RR 05-06® motorcycle engine, renowned for its 600 c.c. displacement and exceptional power-to-weight ratio, emerges as a popular choice. However, as this engine is originally equipped with a wet sump lubrication system (featuring deep wet sumps to prevent oil starvation during turns), this presents challenges when adapted to Formula Society of Automotive Engineers (FSAE) cars. Cornering leads to significant pressure drops, as sloshing exposes the pickup port, causing consequential engine issues. To tackle sloshing-related challenges and pressure loss during lateral and longitudinal g-forces, a dry sump lubrication system was introduced in the Formula car. The dry sump system also lowers the engine’s center of gravity, by reducing sump height. However, transitioning to the dry sump system and integrating it with the existing engine demanded extensive design modifications to various components, including the oil reservoir, lubrication lines, scavenging pump, and oil ports. These adjustments were essential to achieve the targeted elevation in oil pressures at higher engine RPMs. A relationship between the engine oil pressure and the engine RPM was developed as part of the study.

Signal Compensation Control With DDPG-Based Tuning Strategy for Electronic Throttle System

The electronic throttle system (ETS) is one of the important components of an automobile engine that adjust the engine air intake to directly affect the combustion power of the engine. In practical scenarios, Proportional-Integral-Derivative (PID) is a common and effective method. However, the traditional PID is difficult to satisfy the ETS performance requirements, e.g., the system response overshoot is not allowed to exist. Moreover, the controller gains are also difficult to tune manually. To tackle the above-mentioned issues, we propose a signal compensation control framework with an adaptive gain tuning strategy for the electronic throttle system, which consists of an upper-level to tune controller gains and a lower-level signal compensation controller to eliminate the nonlinear terms. The main feature of the signal compensation controller relies on two nonlinear compensators to remove the strong nonlinearity and uncertainty in the actual throttle system. Furthermore, we develop an adaptive gain tunning strategy based on Deep Deterministic Policy Gradient (DDPG) algorithm, and we analyze the corresponding stability and convergence properties of the proposed method. Finally, we illustrate the proposed algorithm on benchmarks and the tracking control problem using the real-world experiment platform of the ETS to show the effectiveness of the proposed algorithm.

Multi-person interaction in collaborative virtual conference for Metaverse

Virtual conferences have successfully solved the challenges of traditional face-to-face conferences that can’t be carried out smoothly due to issues such as venue, transportation, and the pandemic. More importantly, as virtual conferences continue to develop and mature, they provide a virtual environment for multi-person collaboration, which is impossible to achieve with traditional face-to-face conferences. This technological innovation is expected to bring significant cost savings to various fields such as medical care, education, and industry. This paper proposes a unity-based multi-party collaborative virtual conference model. The model takes automobiles as the theme, which can realize the design and modification of the appearance of the automobiles by multiple people in the same space, and also supports operations such as the disassembly and installation of the automobile engine. This model is designed to deepen our understanding of multi-person collaboration capabilities in virtual conferences, a feature that is expected to significantly improve teamwork efficiency.

S-method based on modified group delay for time-frequency analysis

A noise robust time-frequency representation based on the S-method (SM) and modified group delay (MGD) (S-MGD) is proposed in this article. The SM is free from cross-terms as it is the sum of individual Wigner distributions of different signal components and provides high-energy concentration both in time and frequency. The MGD reduces the Gibbs ripple and spurious spectral peaks because of noise, without using any frequency smoothing, and thus maintains the best frequency resolution as that of rectangular window. Hence,a combination of SM and MGD provides the desirable features of both the methods. The proposed method is tested for different signals like time varying random process, frequency shift keying, synthesized car engine sound/pressure signals using a solo combustion and a real-time echolocation pulse emitted by a big brown bat (Eptesicus fuscus) which indicate that the new S-MGD has improved noise immunity and frequency resolution compared to the method that uses frequency smoothing to suppress noise and Gibbs effects.

A STUDY OF THE RELATIONSHIP BETWEEN THE OCTANE NUMBER AND THE CHEMICAL COMPOSITION OF REGULAR, MIDGRADE, AND PREMIUM GASOLINE

The present study was conducted at Zakho City in Northern Iraq to evaluate three different types of gasoline: Regular, Midgrade, and Premium. These types of gasoline are categorized based on their octane rating, which was measured to verify their classification. The results showed that the initial classification was accurate, with respective values of 87.5, 89.8, and 91.1. The study evaluated the three grades of gasoline available at Zakho Gas Stations in Northern Iraq, including Regular, Midgrade, and Premium. The study also compared the chemical composition of the three gasoline grades in terms of aromatics, olefin, sulfur content, and oxygen content. All the three gasoline grades met the American Society for Testing and Materials (ASTM) standard for chemical composition, and all had acceptable specific gravities. However, Midgrade gasoline is not recommended for use during the summer due to its high Reid vapor pressure (RVP) value, low Initial boiling point (IBP), and final boiling point( FBP). In general, the study showed that the Regular and Premium gasoline types sold in North of Iraq meet international quality standards. However, Midgrade gasoline is not recommended for use during the summer due to its high RVP value, low IBP, and FBP, which can lead to increased volatility and environmental pollution, Moreover, using this type of gasoline may cause problems with the car engine.

Coil Parameter Analysis for Inductively Coupled Wireless Charging for Electric Vehicles

Wireless charging (WC) has gained popularity for the charging of electric vehicles in recent years of research, particularly dynamic wireless charging systems (DWCSs). Among the different topologies of DWCSs, this paper focuses on an inductively coupled wireless charging system (ICWCS). In this ICWCS, double-D (DD) coils create horizontal and vertical flux components between different pad configurations, which show optimal features in contrast to circular pad coils. In this work, the three-dimensional (3D) finite element technique (FEM) is used to establish the proposed design to observe the coupling coefficient, while the system design’s performance is evaluated using a circuit simulator. In the simulation, the proposed DD coil configuration is used for both the transmitter and receiver sides. It provides the maximum coupling coefficient and efficiency at perfect alignment when using an in-between air gap of 166 mm and six I-type ferrite bars on the transmitter side and five I-type ferrite bars on the receiver side. The coupling coefficient and system parameters, such as power and efficiency, are considered for different misalignments in the proposed configuration. The results of this work satisfy the Society of Automotive Engineers (SAE) J2954 Class 3 criteria. The best results obtained are on account of optimizing the ferrite core, which is achieved by varying its length and width. While varying the ferrite core’s dimensions, 0.2451, as the optimal k value, is obtained at the effective width and length of 57.5 mm and 400 mm, respectively. The simulation results of the Ansys Maxwell 3D software prove the feasibility of the proposed structure.