Browse Topic: Research and development

Items (11,306)
Dedicated lanes provide a simpler operating environment for ADS-equipped vehicles than those shared with other roadway users including human drivers, pedestrians, and bicycles. This final report in the Automation and Infrastructure series discusses how and when various types of lanes whether general purpose, managed, or specialty lanes might be temporarily or permanently reserved for ADS-equipped vehicles. Though simulations and economic analysis suggest that widespread use of dedicated lanes will not be warranted until market penetration is much higher, some US states and cities are developing such dedicated lanes now for limited use cases and other countries are planning more extensive deployment of dedicated lanes. Automated Vehicles and Infrastructure: Dedicated Lanes includes a review of practices across the US as well as case studies from the EU and UK, the Near East, Japan, Singapore, and Canada. Click here to access the full SAE EDGETM Research Report portfolio.
Coyner, KelleyBittner, Jason
The objective of this experimental study was to investigate the change of shifting rate of metal V-belt type CVT during speed up/down under quasi-idle loading condition. Changes in the rotational speeds of the driving and driven pulleys were simultaneously measured by the rotational speed sensors installed on the driving and driven shafts during speed up/down shifting, respectively. In addition, the interaxial force applied to the driving and driven pulleys was measured by a load cell. The shifting rate was defined as the ratio of the calculated radial displacement to the tangential displacement of the belt in the pulley groove. This study found that the shifting rate was determined not only by the slippage between the pulley and the belt element, but also by the elastic deformation of the belt element in the pulley groove. The power transmission performance was improved when the elastic deformation was small even though radial slippage between the pulley and the belt element was
Mori, YuichirouOkubo, KazuyaObunai, Kiyotaka
Topology optimization (TO) in electrochemical systems has recently attracted many researchers. Previous studies suggested minimal performance differences between 2D and 3D designs, indicating that 2D models suffice to enhance performance, especially in unidirectional flow scenarios. A later study found that the concentration distribution in an optimized 2D flow system differed from that in a unidirectional flow system. We posited that pulsating flow could further enhance the performance of such systems. First, we initiated TO for a diffusion-reaction system in a steady state. The optimized structure obtained from this process served as the foundation for subsequent investigations involving a pulsating flow source in convection-diffusion-reaction systems. We introduced two different systems with distinct flow natures: one characterized by a flow nature of 1D and the other by a flow nature of 2D. The results demonstrated that the optimized structure with a heterogeneous distribution
Long, MenglyAlizadeh, MehrzadSun, PengfeiCharoen-amornkitt, PatcharawatSuzuki, TakahiroTsushima, Shohji
In commercially available electric motorcycles, there is a notable shift in the cooling method, moving from air cooling to water cooling, and in the winding method, moving from concentrated winding to distributed winding, as the output increases. This shift occurs around 8 to 10 kW. However, there is a paucity of empirical investigations examining these combinations to ascertain their optimality. In order to verify this trend, a verification model has been constructed which allows for the comparison of the capacity and weight of the motor and cooling system according to the vehicle’s required output and thermal performance. A comparison and verification of the combinations of winding methods (concentrated winding or segment conductor distribution winding) and cooling systems (water-cooled or air-cooled) was conducted using the model that had been constructed. In the motor designed for this study, when the maximum output of the vehicle was 35 kW or less (European A2 license), the total
Otaki, RyotaTsuchiya, TeruyukiSakai, YuYamauchi, TakuyaShimizu, Tsukasa
This study examines the acoustic properties of engine-knocking sounds in gasoline engines, arising from misfires during spark ignition that negatively affect driving performance. The aim was to understand the frequency characteristics of acceleration sounds and their connection to the proximity of the order components. The study also explores “booming,” where two different frequencies of sounds occur simultaneously, potentially linked to the unpleasant nature of engine knocking. Using a sinusoidal model, we generated engine acceleration sound models with 5th-, 10th-, and 15th-order components, including engine knocking. Two types of sound stimuli were created: one with the original amplitude (OA) and one with a constant amplitude (CA) for each component order, emphasizing the order-component proximity in CA sounds. Aural experiments with 10 participants in an anechoic room using headphones and the MUSHRA method revealed an inverse relationship between OA and CA ratings as the component
Suzuki, RyuheiIshimitsu, ShunsukeNitta, MisakiSakakibara, MikaHakozaki, TomoyukiFujikawa, SatoshiIwata, KiyoakiMatsumoto, MitsunoriKikuchi, Masakazu
Ride comfort is an important factor in the development of vehicles. Understanding the characteristics of seat components allows more accurate analysis of ride comfort. This study focuses on urethane foam, which is commonly used in vehicle seats. Soft materials such as urethane foam have both elastic and viscous properties that vary with frequency and temperature. Dynamic viscoelastic measurements are effective for investigating the vibrational characteristics of such materials. Although there have been many studies on the viscoelastic properties of urethane foam, no prior research has focused on dynamic viscoelastic measurements during compression to simulate the condition of a person sitting on a seat. In this study, dynamic viscoelastic measurements were performed on compressed urethane foam. Moreover, measurements were conducted at low temperatures, and a master curve using the Williams–Landel–Ferry (WLF) formula (temperature–frequency conversion law) was created.
Kamio, ChihiroYamaguchi, TakaoMaruyama, ShinichiHanawa, KazutoIwase, TsutomuHayashi, TatsuoSato, ToshiharuMogawa, Hajime
The EU currently has very ambitious plans for the electrification of vehicles, particularly in the field of urban logistics. For example, the so-called “Transport White Paper” [1] aims to achieve essentially CO2-free logistics in major urban centers by 2030, while “Europe on the move” [2] has presented a series of legislative initiatives. The Strategic Research and Innovation Agenda for Transport proposes research priorities and actions to deploy innovative solutions, with a particular focus on the electrification of transport. Numerous advancements in electromobility have led to a growing number of vehicles available in various areas, particularly in urban logistics. New concepts like cargo bikes and micro-vehicles are being developed, but they cannot fully replace traditional light commercial vehicles. While some electrified options exist, they are often modified versions of existing platforms with internal combustion engines swapped for electric drives. The research work in this
Königshofer, ThomasTromayer, JürgenSchacht, Hans-JürgenWang, Eric
In order to rapidly achieve the goal of global net-zero carbon emissions, ammonia (NH3) has been deemed as a potential alternative fuel, and reforming partial ammonia to hydrogen using engine exhaust waste heat is a promising technology which can improve the combustion performance and reduce the emission of ammonia-fueled engines. However, so far, comprehensive research on the correlation between the reforming characteristic for accessible engineering applications of ammonia catalytic decomposition is not abundant. Moreover, relevant experimental studies are far from sufficient. In this paper, we conducted the experiments of catalytic decomposition of ammonia into hydrogen based on a fixed-bed reactor with Ru-Al2O3 catalysts to study the effects of reaction temperature, gas hour space velocity (GHSV) and reaction pressure on the decomposition characteristics. At the same time, energy flow analysis was carried out to explore the effects of various reaction conditions on system
Li, ZeLi, TieChen, RunLi, ShiyanZhou, XinyiWang, Ning
The relation between the multiple auto-ignition in the premixed charge with fuel concentration distribution and associated pressure wave are numerically investigated. This study assumes that the auto-ignition phenomenon in the end-gas of PCCI combustion, a next-generation combustion method which is expected to achieve both low fuel consumption and low emissions at a high level. Detailed numerical analysis considering the elementary chemical reactions of the compressible reacting fluid flow described in the one-dimensional coordinate system with high spatial and time resolution was performed to clarify the detailed phenomena of the onset of the multiple auto-ignition and the pressure wave propagation in the gas.
Iizumi, KotaYoshida, Kenji
Multiple-ion-probe method consists of multiple ion probes placed on the combustion chamber wall, where each individual ion probe detects flame contact and records the time of contact. From the recorded data, it is also possible to indirectly visualize the inside of the combustion chamber, for example, as a motion animation of moving flame front. In this study, a thirty-two ion probes were used to record flames propagating in a two-stroke gasoline engine. The experiment recorded the combustion state in the engine for about 3 seconds under full load at about 6500 rpm, and about 300 cycles were recorded in one experiment. Twelve experiments were conducted under the same experimental conditions, and a total of 4,164 cycles of signal data were obtained in the twelve experiments. Two types of analysis were performed on this data: statistical analysis and machine learning analysis using a linear regression model. Statistical analysis calculated the average flame detection time and standard
Yatsufusa, TomoakiOkahira, TakehiroNagashige, Kohei
In this study, an initial approach using deep reinforcement learning to replicate the complex behaviors of motorcycle riders was presented. Three learning examples were demonstrated: following a target velocity, maintaining stability at low speeds, and following a target trajectory. These examples serve as a starting point for further research. Additionally, the proficiency of the constructed models was examined using rider proficiency evaluation methods developed in previous studies. Initial results indicated that the models have the potential to mimic real rider behaviors; however, challenges such as differences between the model’s output and what humans can produce were also identified for future work.
Mitsuhashi, YasuhiroMomiyama, YoshitakaYabe, Noboru
This paper explores methods to enhance the sound quality of V6 outboard engines. Previous research in the boat and outboard engine domain has underscored the importance of enhancing sound quality. Specific preferences and desired directions for outboard engine sound quality have been identified. It’s been suggested that controlling intake sound and gear noise is important to achieving desired sound quality according to customer preferences. However, there are few examples of methods for achieving this. This study aims to develop methods for enhancing sound quality by emphasizing low-frequency sounds through intake sound. Initially, various methods were evaluated, and intake valve timing modification was chosen. Simple simulations confirmed that delaying valve timing for some cylinders may introduce characteristics that are not present in conventional cases. Subsequent 1D simulations identified optimal intake valve timing, balancing intake pressure characteristics and horsepower
Muramatsu, HidetaMatsumoto, TaroNaoe, GakuKondo, Takashi
New regulations introduced by the Fédération Internationale de l’Automobile (FIA) for the 2026 Formula 1 season mark the first instance of active flow control methods being endorsed in Formula 1 competition. While active methods have demonstrated significant success in airfoil development, their broader application to grounded vehicle aerodynamics remains unexplored. This research investigates the effectiveness of trapped vortex cavity (TVC) technology in both active and passive flow controls, applied to a NACA0012 airfoil and an inverted three-element airfoil from a Formula 1 model. The investigation is conducted using numerical methods to evaluate the aerodynamic performance and potential of TVC in this paper. In the single-airfoil case, a circular cavity is placed along the trailing edge (TE) on the suction surface; for the three-element airfoils, the cavity is positioned on each airfoil to determine the optimum location. The results show that the presence of a cavity, particularly
Ng, Ming KinTeschner, Tom-Robin
This study aims to predict the impact of porosities on the variability of elongation in the casting Al-10Si-0.3Mg alloy using machine learning methods. Based on the dataset provided by finite element method (FEM) modeling, two machine learning algorithms including artificial neural network (ANN) and 3D convolutional neural network (3D CNN) were trained and compared to determine the optimal model. The results showed that the mean squared error (MSE) and determination coefficient (R2) of 3D CNN on the validation set were 0.01258/0.80, while those of ANN model were 0.28951/0.46. After obtaining the optimal prediction model, 3D CNN model was used to predict the elongation of experimental specimens. The elongation values obtained by experiments and FEM simulation were compared with that of 3D CNN model. The results showed that for samples with elongation smaller than 9.5%, both the prediction accuracy and efficiency of 3D CNN model surpassed those of FEM simulation.
Zhang, Jin-shengZheng, ZhenZhao, Xing-zhiGong, Fu-jianHuang, Guang-shengXu, Xiao-minWang, Zhi-baiYang, Yutong
In recent years, researchers have increasingly focused on ammonia–diesel dual-fuel engines as a means of reducing CO2 emissions. Analyzing in-cylinder combustion processes is essential for optimizing the performance of ammonia–diesel dual-fuel engines. However, there is currently a lack of suitable reaction kinetics models for ammonia–diesel engine conditions. In this study, the ignition delay of ammonia/n-heptane mixtures was measured, and a reduced chemical mechanism was developed. Using rapid compression machine (RCM) experiments, the ignition delays of ammonia/n-heptane mixtures with different ammonia energy fractions (AEFs) (40%, 60%, and 80%) were measured. The test pressure ranged from 1.5 to 3.0 MPa, while the temperature ranged from 667 to 919 K, with an equivalence ratio of 1. The results showed that as the AEFs increased, the ignition delay of the premixed mixture also increased. When the AEF was 40%, the ammonia/n-heptane premixed mixture exhibited the negative temperature
Cai, KaiyuanLiu, YiChen, QingchuQi, YunliangLi, LiWang, Zhi
Toyota vehicles equipped with Toyota Safety Sense (TSS) can record detailed information surrounding various driving events, including crashes. Often, this data is employed in accident reconstruction. TSS data is comprised of three main categories: Vehicle Control History (VCH), Freeze Frame Data (FFD), and image records. Because the TSS data resides in multiple Electronic Control Units (ECUs), the data recording is susceptible to catastrophic power loss. In this paper, the effects of a sudden power loss on the VCH, FFD, and images are studied. Events are triggered on a TSS 2.5+ equipped vehicle by driving toward a stationary target. After system activation, a total power loss is induced at various delays after activation. Results show that there is a minimum time required after system initiation in order to obtain full VCH, FFD, and image records. Power losses occurring within this time frame produce incomplete records. Data accuracy is unaffected, even in partial records.
Getz, CharlesDiSogra, MatthewSpivey, HeathJohnson, TaylorPatel, Amit
Abstract Real-world driving data is an invaluable asset for several types of transportation research, including emissions estimation, vehicle control development, and public infrastructure planning. Traditional methods of real-world driving data collection use expensive GPS-based data logging equipment which provide advanced capabilities but may increase complexity, cost, and setup time. This paper focuses on using the Google Maps application available for smartphones due to the potential to scale-up real-world driving data logging. Samples of the potential data processing and information that can be gathered by such a logging methodology is presented. Specifically, two months of Google Maps driving data logged by a rural Michigan resident on their smartphone may provide insights on their driving range, duration, and geographic area of coverage (AOC) to guide them on future vehicle purchase decisions. Aggregating such statistics from crowd-sourcing real-world driving data via Google
Manoj, AshwinYin, SallyAhmed, OmarVaishnav, ParthStefanopoulou, AnnaTomkins, Sabina
The Autocycle is a style of vehicle that most often utilizes a reverse-tricycle design with two front wheels and a single rear wheel. Modern autocycles in the United States are often utilized in a recreational role. This work presents physical measurements of two modern autocycles for use in accident reconstruction and pursues a deeper understanding of the unique attributes and handling associated with these vehicles. Vehicles were used to measure physical properties and subjected to cornering tests presented herein, and the data is compared to that for a conventional automobile. Observations on tire scuff marks are made from cornering tests unique to these vehicles. Strengths and challenges with this type of vehicle design are presented for various use cases as compared to conventional automobiles. Data and knowledge from this study are published to aid accident reconstruction efforts.
Warner, WyattSwensen, GrantWarner, Mark
In this paper, the equivalent elliptic gauge pendulum model of liquid sloshing in tank is established, the pendulum dynamic equation of tank in non-inertial frame of reference is derived, and the dynamics model of tank transporter is constructed by force analysis of the whole vehicle. A liquid tank car model was built in TruckSim to study its dynamic response characteristics. Aiming at the problem that the coupling effect between liquid sloshiness in tank and tank car can easily affect the rolling stability of vehicle, the roll dynamics model of tank heavy vehicle is established based on the parameterized equivalent elliptic gauge single pendulum model, and the influence of different lateral acceleration and suspension system on the roll stability is studied. The results show that the coupling effect between the motion state of the tank car and the liquid slosh lengthens the oscillation period of the liquid slosh in the tank, and the amplitude of the load transfer rate of the tank car
Yukang, Guo
The study analyzed data from on-road drives with a pre-production Level 2 (L2) partial automation system using a sample of 27 drivers ranging from 21 to 75 years of age. The system provides continuous automatic lateral and longitudinal control but requires the driver to remain attentive and intervene when necessary. The L2 system was equipped with a Driving Monitoring System (DMS) that issued escalating alerts to remind the driver to pay attention or take over when needed. During the 14-month study period, drivers completed 354,768 miles of travel with the L2 system engaged, totaling 5,913 trips. The results of the study showed that drivers were highly responsive to attention reminders and takeover alerts, with high compliance rates and quick response times. Importantly, there was no evidence of habituation to these alerts over time. These findings support the effectiveness of the system's DMS and alert HMI (Human-Machine Interface) strategy in promoting the proper use of the system
Llaneras, RobertGlaser, YiGreen, CharlesAugust, MaureenLandry, Steven
Technology development for enhancing passenger experience has gained attention in the field of autonomous vehicle (AV) development. A new possibility for occupants of AVs is performing productive tasks as they are relieved from the task of driving. However, passengers who execute non-driving-related tasks are more prone to experiencing motion sickness (MS). To understand the factors that cause MS, a tool that can predict the occurrence and intensity of MS can be advantageous. However, there is currently a lack of computational tools that predict passenger's MS state. Furthermore, the lack of real-time physiological data from vehicle occupants limits the types of sensory data that can be used for estimation under realistic implementations. To address this, a computational model was developed to predict the MS score for passengers in real time solely based on the vehicle's dynamic state. The model leverages self-reported MS scores and vehicle dynamics time series data from a previous
Kolachalama, SrikanthSousa Schulman, DanielKerr, BradleyYin, SiyuanWachsman, Michael BenPienkny, Jedidiah Ethan ShapiroJalgaonkar, Nishant M.Awtar, Shorya
In-Mold Graining (IMG) is an innovative production technology applied to the skin wrapping of automotive interior components. In the design of automotive interior components of door panels and instrument clusters, to overcome process-related problems, such as the thinning of grain patterns and excessive reduction in thickness, simulation of the skin vacuum forming process is required. The Thermoplastic Olefin (TPO) skin material is investigated in this paper, and a viscoelastic mechanical model for this material is established. Dynamic Mechanical Analyzer (DMA) is utilized to perform scan for frequency and temperature, and the tested data is used to obtain key model parameters of the viscoelastic constitutive model. Based on the experimental data, the study explores how to calculate the relaxation time spectrum to describe the viscoelastic properties of TPO material during the vacuum forming process. Numerical simulation of the vacuum forming process of TPO material is conducted using
Chai, BingjiGuo, YimingXie, XinxingZhang, Qu
Battery health status and driving rangeof electric vehicles (EVs) are critical factors in determining their market penetration. Choosing an optimal charging strategy—specifying how, when, and for how long to charge based on the driver’s travel behavior—can significantly mitigate battery degradation and extend battery life. This study introduces an EV powertrain system energy model designed to enhance the prediction accuracy of battery status under real-world driving conditions. By integrating with the Q-learning approach, this studyprovides tailored recommendations on charging behaviors, including charger type, start time, and charging duration. This study innovatively considers the rental costs caused by the battery capacity not being able to meet the daily driving range. Simulating a typical three-year usage scenario for an average driver in New England, the results indicate that thecharging strategy proposed by this study reduces battery degradation rates by 1.53‰, 3.57‰, and 7.68
Wang, JiayiJing, HaoOu, Shiqi (Shawn)Lin, Zhenhong
Model-Based Systems Engineering (MBSE) enables requirements, design, analysis, verification, and validation associated with the development of complex systems. Obtaining data for such systems is dependent on multiple stakeholders and has issues related to communication, data loss, accuracy, and traceability which results in time delays. This paper presents the development of a new process for requirement verification by connecting System Architecture Model (SAM) with multi-fidelity, multi-disciplinary analytical models. Stakeholders can explore design alternatives at a conceptual stage, validate performance, refine system models, and take better informed decisions. The use-case of connecting system requirements to engineering analysis is implemented through ANSYS ModelCenter which integrates MBSE tool CAMEO with simulation tools Motor-CAD and Twin Builder. This automated workflow translates requirements to engineering simulations, captures output and performs validations. System
Upase, BalasahebShroff, Roopesh
A new method for bearing preload measurement has shown potential for both high accuracy and fast cycle time using the frequency response characteristics of the power transmission system. One open problem is the design of the production controller, which relies on a detailed sensitivity study of the system frequency response to changes in the bearing and system design parameters. Recently, an analytical model was developed for multi-row tapered roller bearings that includes all appropriate bearing and power transmission system design parameters. During the assembly process, some of the parameters related to the roller positions cannot be controlled. These parameters include the actual position of the first roller compared to the vertical axis, the relative position of the rollers between the bearing rows, and others. This work presents a sensitivity analysis of the effects of those uncontrollable parameters on the analytical model. The sensitivity study determines the percentage change
Gruzwalski, DavidMynderse, James
In this study, the aerodynamics and surface flow field of a 1/5 scale SUV vehicle model called “AeroSUV” were experimentally investigated. The aerodynamics and surface flow field investigations were carried out in the wind tunnel at Hiroshima University with a Reynolds number ReL = 1.2×106, baseline yaw angle β = 0° and crosswind conditions β = 5°, 10° and 15° for two rear ends, Estateback and Fastback. The results provide aerodynamic information and detailed surface flow field information for a standard middle-class SUV vehicle with different rear ends, which is important for automotive design. By applying GLOF measurements to automotive aerodynamics, the skin friction topology was revealed in detail as surface flow field information that is useful for understanding the physics of the flow. The skin friction topology clearly shows the separation lines, reattachment lines, and focus points associated with the separation flow, longitudinal vortices and recirculation vortices of this
Hijikuro, MasatoShimizu, KeigoNakashima, TakujiHiraoka, Takenori
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
Hydro-pneumatic suspension is widely used due to its favorable nonlinear stiffness and damping characteristics. However, with the presence of parameter uncertainties and high nonlinearities in the hydro-pneumatic suspension system, the effectiveness of the controller is often suboptimal in practical applications. To mitigate the influence of these issues on the control performance, an adaptive sliding mode control method with an expanded state observer (ESO) is proposed. Firstly, a nonlinear mathematical model of hydro-pneumatic suspension, considering seal friction, is established based on the hydraulic principle and the knowledge of fluid mechanics. Secondly, the ESO is designed to estimate the total disturbance caused by the nonlinearities and uncertainties, and it is incorporated into the sliding mode control law, allowing the control law to adapt to the operating state of the suspension system in real time, which solves the effect of uncertainties and nonlinearities on the system
Niu, ChangshengLiu, XiaoangJia, XingGong, BoXu, Bo
A passenger vehicle hood is designed to meet Vulnerable Road User (VRU) regulatory requirements and consumer metric targets. Generally, hood inner design and its reinforcements, along with deformable space available under the hood are the main enablers to meet the Head Impact performance targets. However, cross functional balancing requirements, such as hood stiffness and packaging space constraints, can lead to higher Head Injury Criteria (HIC15) scores, particularly when secondary impacts are present. In such cases, a localized energy absorber is utilized to absorb the impact energy to reduce HIC within the target value. The current localized energy absorber solutions include the usage of flexible metal brackets, plastic absorbers etc. which have limited energy absorbing capacity and tuning capability. This paper focuses on usage of a novel 3D printed energy absorbers, based on various kinds of lattice structures. These absorbers are either sandwiched between the inner and the outer
Kinila, VivekanandaAgarwal, VarunV S, RajamanickamTripathy, BiswajitGupta, Vishal
Precise state estimation during a lateral maneuver is not just a theoretical concept but a practical necessity. The performance of the Kalman filter is directly impacted by the comprehensive research and innovative approaches to counter nonlinearity and uncertainty. The use of machine learning in control theory is one such development that has significantly enhanced the effectiveness of our work. This paper provides an enhanced adaptive Kalman filter architecture with a neural network for a rapid obstacle avoidance maneuver. The proposed design exemplifies not just its effectiveness in terms of better state estimation in the presence of complex nonlinear vehicle dynamics and disturbances but also its potential downsides sometimes. Simulation results verify the same by ensuring a significant improvement to the traditional design, demonstrating better accuracy and the need for such advances in vehicle dynamics and control.
Sudhakhar, Monish Dev
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