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Abstract 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® 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.”

Abstract In this study, a novel assessment approach of in-vehicle speech intelligibility is presented using psychometric curves. Speech recognition performance scores were modeled at an individual listener level for a set of speech recognition data previously collected under a variety of in-vehicle listening scenarios. The model coupled an objective metric of binaural speech intelligibility (i.e., the acoustic factors) with a psychometric curve indicating the listener’s speech recognition efficiency (i.e., the listener factors). In separate analyses, two objective metrics were used with one designed to capture spatial release from masking and the other designed to capture binaural loudness. The proposed approach is in contrast to the traditional approach of relying on the speech recognition threshold, the speech level at 50% recognition performance averaged across listeners, as the metric for in-vehicle speech intelligibility.

Abstract The exponentially growing electrification market is driving demand for lithium-ion batteries (LIBs) with high performance. However, LIB thermal runaway events are one of the unresolved safety concerns. Thermal runaway of an individual LIB can cause a chain reaction of runaway events in nearby cells, or thermal propagation, potentially causing significant battery fires and explosions. Such a safety issue of LIBs raises a huge concern for a variety of applications including electric vehicles (EVs). With increasingly higher energy-density battery technologies being implemented in EVs to enable a longer driving mileage per charge, LIB safety enhancement is becoming critical for customers. This comprehensive review offers an encompassing overview of prevalent abuse conditions, the thermal event processes and mechanisms associated with LIBs, and various strategies for suppression, prevention, and mitigation.

Abstract The cooperative platoon of multiple trucks with definite proximity has the potential to enhance traffic safety, improve roadway capacity, and reduce fuel consumption of the platoon. To investigate the truck platooning performance in a real-world environment, two Peterbilt class-8 trucks equipped with cooperative truck platooning systems (CTPS) were deployed to conduct the first-of-its-kind on-road commercial trial in Canada. A total of 41 CTPS trips were carried out on Alberta Highway 2 between Calgary and Edmonton during the winter season in 2022, 25 of which were platooning trips with 3 to 5 sec time gaps. The platooning trips were performed at ambient temperatures from −24 to 8°C, and the total truck weights ranged from 16 to 39 tons. The experimental results show that the average time gap error was 0.8 sec for all the platooning trips, and the trips with the commanded time gap of 5 sec generally had the highest variations.

Abstract The electrically interconnected suspension (EIS) is a novel suspension system that has gained attention due to its potential to improve vehicle vibration control. This article provides a comprehensive review of EIS and related technologies. It starts with an overview of the research on hydraulic interconnected suspension (HIS) and its limitations. Then, it discusses the development of the electromagnetic suspension (EMS) and its advantages in adjusting mechanical characteristics. The article focuses on the electrical network and decoupling control characteristics of EIS, demonstrating the principle of synchronous decoupling control of multiple vibration modes. A comparison of the structure and control characteristics of EIS and HIS highlights the advantages of EIS in vehicle vibration control.

Abstract Numerous researchers are committed to finding solutions to the path planning problem of intelligence-based vehicles. How to select the appropriate algorithm for path planning has always been the topic of scholars. To analyze the advantages of existing path planning algorithms, the intelligence-based vehicle path planning algorithms are classified into conventional path planning methods, intelligent path planning methods, and reinforcement learning (RL) path planning methods. The currently popular RL path planning techniques are classified into two categories: model based and model free, which are more suitable for complex unknown environments. Model-based learning contains a policy iterative method and value iterative method. Model-free learning contains a time-difference algorithm, Q-learning algorithm, state-action-reward-state-action (SARSA) algorithm, and Monte Carlo (MC) algorithm.

Abstract This article explores the value of simulation for autonomous-vehicle research and development. There is ample research that details the effectiveness of simulation for training humans to fly and drive. Unfortunately, the same is not true for simulations used to train and test artificial intelligence (AI) that enables autonomous vehicles to fly and drive without humans. Research has shown that simulation “fidelity” is the most influential factor affecting training yield, but psychological fidelity is a widely accepted definition that does not apply to AI because it describes how well simulations engage various cognitive functions of human operators. Therefore, this investigation reviewed the literature that was published between January 2010 and May 2022 on the topic of simulation fidelity to understand how researchers are defining and measuring simulation fidelity as applied to training AI.

Abstract In order to improve the squeak and rattle (S&R) performance level of automotive interiors, the contact nonlinear characteristics of structural components need to be considered when performing interior noise analysis. The finite element model of S&R analysis of the interior assembly is built, and the time-domain vibration characteristics of the contact points between the interior panels are analyzed by applying external forced excitation. The interaction force between contact points is obtained according to the contact equivalent model between interior materials. The external excitation and internal interaction force are analyzed as the total excitation to obtain the response results. Through experimental verification, compared with the S&R performance division method, the analysis results are consistent with the test results. Based on this model, S&R risk optimization is carried out, and the risk level is significantly reduced.

Abstract ERRATUM

Abstract A comprehensive literature review of the optimization techniques used for the process parameter optimization of Abrasive Jet Machining (AJM), Ultrasonic Machining (USM), Laser Beam Machining (LBM), Electrochemical Machining (ECM), and Plasma Arc Machining (PAM) are presented in this review article. This review article is an extension of the review work carried out by previous researchers for the process parameter optimization of non-traditional machining processes using various advanced optimization algorithms. The review period considered for the same is from 2012 to 2022. The prime motive of this review article is to find out the sanguine effects of various optimization techniques used for the optimization of various considered objectives of selected non-traditional machining processes in addition to deemed materials and foremost process parameters.

Abstract Sound quality assessments are an integral part of vehicle design. Especially now, as manufacturers move towards electrification, vehicle sounds are fundamentally changing. By improving the quality of the interior sounds of a vehicle, consumers’ subjective evaluation of it can be increased. Therefore, the field of psychoacoustics, which is the study of human perception of sound, is broadly applicable here. In fact, the perceived quality of a sound signal is influenced by several psychoacoustic indicators, including loudness, sharpness, and roughness. Of particular utility is identifying in advance how to distribute audible frequency content in a way that optimizes psychoacoustic metrics as this can help automotive engineers obtain specific design targets that optimize vehicle noise, vibration, and harshness (NVH). In this article, a novel modified gradient-based optimization technique (MGOT) is developed to optimize psychoacoustic loudness and sharpness.

Abstract A typical modern automobile compressor-driven air conditioner, about powerful enough to cool a house, may not be needed even in very hot, humid climates if we combine insights from comfort theory with innovations in comfort delivery, photonics, and superefficient thermal and air-handling devices. Recent advances can successively minimize unwanted heat gain into the passenger cabin, cool people’s bodies rather than the vehicle, deliver highly effective radiant cooling, passively reject extracted heat to the sky, and, if needed, move air very efficiently and quietly to expand the human comfort range. Together these proven innovations may give automotive occupants excellent hot-weather comfort without refrigerative air conditioning.

Abstract With the increasing electrification of road vehicle powertrains, new NVH challenges are emerging. Due to the temporary deactivation of the internal combustion engine or even its complete elimination, the interior sound is primarily determined by noise shares of the electrical components and shares of tire and wind noise. In particular, the high-frequency tonal noise components induced by the electric powertrain are often dominant. These components usually have a negative impact on the perceived sound quality of the total vehicle. Major noise-causing components of the electric powertrain are the electric machine and the transmission. Since acoustic optimization is a complex and time-consuming process, this article develops and presents a novel method for the automated separation of the noise shares of the electric machine and the transmission gears in the vehicle interior.

Abstract The control of road structure noise has always been the focus and difficulty of automobile vibration and noise reduction. Aiming at the control of road structural noise, a maglev actuator suitable for automobile suspension was designed. First, the working principle of the maglev actuator and the actuator output force with the finite element model were analyzed. Based on this analysis, the structural design of the maglev actuator was completed. Second, based on a domestic SUV passenger car as a platform, the overall layout of the maglev suspension and its control system design were completed, and a suspension model equipped with a maglev actuator was established. Finally, the vibration isolation effect of maglev suspension was compared and analyzed under random road excitation.

Abstract In this article, the method based on the combination of the acoustic perturbation equations and the statistical energy analysis has been used to simulate and optimize the interior aerodynamic noise of a large sport utility vehicle model. The reliability of the method was verified by comparing the analysis results with the wind tunnel test. Influenced by the main noise sources such as A-pillar, exterior rearview mirror, and front sidewindow, the wind noise of the model was significantly greater than that of the same class. To improve the wind noise performance, the side mirror was optimized with the method, including the minimum distance between the rearview mirror and the triangle trim cover, the angle between the rearview mirror and the front sidewindow, and the shell groove of the rearview mirror. The simulation results show that the overall sound pressure level in the car decreases by 2.12 dBA and the articulation index increases by 4.04% after optimization.

Abstract Aiming at solving the battery electric vehicle (BEV) problems of high energy consumption and low efficiency in heating at low temperature, this study takes the thermal management system of BEV as the research object and develops an integrated thermal management control system based on heat pump air-conditioning for BEV. First, the functional requirements and optimal operating temperature range of each BEV subsystem are defined. Second, on the basis of the thermodynamic cycle principle of the air-conditioning system and compared with the traditional positive temperature coefficient thermistor (PTC) heating mode, the high heating efficiency and low energy consumption advantages of the heat pump system in winter are highlighted.

Abstract Vehicle aerodynamics has been the subject of extensive research, with a heavy emphasis on the vehicle. Heavy vehicles, such as trucks and buses, have undergone aerodynamic studies in recent years to reduce drag and improve fuel economy [1]. In this study, the distribution of air conditioning in the cabin of a passenger bus was investigated by discussing the factors that influence in attaining the desired thermal comfort values such as temperature distribution, relative humidity ratios, and air velocities inside the bus. The research was conducted on three different cases. In this study, different types of air-conditioning (AC) outlets—linear grills, slots diffusers, and gaspers—were used, and the effect of each outlet on temperature distribution, air velocities, and relative humidity ratios within the bus was investigated. In all three cases, the inlet air velocity was set to 0.8 m/s, and the return air was combined in the middle of the bus.

Abstract Electric Vehicle (EV) motors and batteries do not create heat in the same way as internal combustion engines; therefore, new specific thermal management solutions are required. Thus the development of adequate simulation methodologies to predict the thermal behavior of new devices and their influence on the thermal comfort of the users is a key point of investigation. In this work two different thermal comfort analysis methodologies are presented and compared with climatic chamber tests. The first one is a zero-dimensional (0D) approach, based on the calculation of the different heat fluxe, that predicts the evolution of average temperature in the vehicle cabin and calculates standard comfort index Predicted Mean Vote (PMV). The second one is a Computational Fluid Dynamics (CFD) method coupled with a simplified human comfort model, also called the manikin model; it calculates a detailed thermal analysis of the cabin and gives a comfort index for some body segments.

Abstract Renewable energy sources provide an excellent opportunity for state departments of transportation (DOTs) to benefit from a dual use of land while providing flexible, resilient, affordable, and environmentally responsible modes of generation. Solar photovoltaic (PV) systems are particularly useful in this regard. This study presents a literature review on the types of solar project partnerships, application of solar PV systems by DOTs in the United States (U.S.), solar energy potential, energy policies, and incentives in Virginia. In addition, a feasibility assessment of installing solar PV systems at six (6) Virginia DOT (VDOT)-owned sites is presented. The review of the literature indicated that twenty state DOTs have implemented or are developing solar projects using their facilities. The feasibility assessment showed the benefits of installing solar PV systems at VDOT facilities.

Abstract The innovations of vehicle connectivity have been increasing dramatically to enhance the safety and user experience of driving, while the rising numbers of interfaces to the external world also bring security threats to vehicles. Many security countermeasures have been proposed and discussed to protect the systems and services against attacks. To provide an overview of the current states in this research field, we conducted a systematic mapping study (SMS) on the topic area “security countermeasures of in-vehicle communication systems.” A total of 279 papers are identified based on the defined study identification strategy and criteria. We discussed four research questions (RQs) related to the security countermeasures, validation methods, publication patterns, and research trends and gaps based on the extracted and classified data. Finally, we evaluated the validity threats and the whole mapping process.