Browse Topic: Vehicle drivers

Items (5,029)
Electric vehicles are increasingly important for emission reduction and the promotion of sustainable mobility. Despite their advantages over conventional vehicles, the energy consumption of electric vehicles is heavily influenced by various factors such as driving behavior, elevation profile, and environmental conditions. In particular, the driving style plays a crucial role in determining range and energy consumption. This influence is also observed in the context of the Interreg project FreeE-Bus. This project focuses on the development of optimized charging management for electric buses in the public transport system of the Lake Constance region. Due to strict data protection regulations that prevent a detailed analysis of driver data, assessing the impact of driving styles is difficult. This paper addresses this issue by developing an innovative driver model that simulates different driver types and analyzes their effects on energy consumption. The driver model employs a Model
Konzept, AnjaReick, BenediktMiller, MariusRautenberg, PhilipStörzer, Martin
An optimization framework for trip and charging planning for electric heavy-duty vehicles is proposed in this paper. Building upon and extending previous work on light-duty vehicles, our approach models energy-aware routing by constructing a state-augmented graph that jointly captures geographic position and battery state-of-charge. We refine the route model to include detailed vehicle dynamics and speed constraints specific to heavy-duty vehicles, and introduce an alternative graph construction method that avoids the computational complexity of lexicographic products by generating only feasible nodes. The resulting framework enables efficient trip planning that accounts for driving behavior, road characteristics, and charging infrastructure. Simulation results demonstrate the effectiveness of the approach in reducing energy consumption and ensuring operational feasibility for long-haul freight transport.
Zonetti, DanieleSciarretta, AntonioDe Nunzio, Giovanni
To curb global warming and meet stricter greenhouse gas emission standards all over the globe, it is essential to minimize the carbon footprint of applications in the mobility and transport segment. The demands on mobility, transportation and services are constantly increasing in line with worldwide population growth and the corresponding need for economic prosperity. This ongoing trend will lead to a significant increase in energy requirements for mobility-related applications in the upcoming time, despite all efficiency improvements. The timely introduction and accelerated spread of low-carbon/carbon-neutral energy sources is therefore of crucial importance. In addition to the switch to electric propulsion systems, particularly in the light-duty vehicle sector, the use of advanced and optimized hydrogen (H2)-powered internal combustion engines (ICE) represents a parallel, compatible technical option, as these applications will also meet the most stringent requirements in terms of
Koerfer, ThomasZimmer, PascalLi, ZhenglingPischinger, StefanLückerath, Moritz
Electrification of heavy-duty on-road trucks used for regional freight transportation is a viable option for fleets to reduce operation and maintenance costs and lower their carbon footprint. However, there is considerable uncertainty in projecting their daily range because highly variable payload mass, among other factors, confounds battery state of charge (SOC) prediction algorithms. Previous work by the authors proposed an electric vehicle range prediction model based on two parallel recurrent neural networks (RNNs). The first RNN used mean-variance estimation to output a predicted mean and variance, and the second used bounded interval estimation to provide bounds on the SOC required to complete a trip. The dual RNN approach resulted in estimating the remaining range and error bands of the SOC over the route. The previous work was limited because it did not incorporate driving conditions, like road type and ambient temperature, that affect driver behavior and energy consumption
Jayaprakash, BharatEagon, MatthewNorthrop, William F.
Nowadays, Battery Electric Vehicles (BEVs) are considered an attractive solution to support the transition towards more sustainable transportation systems. Although their well-known advantages in terms of overall propulsion efficiency and exhaust emissions, the diffusion of BEVs on the market is still reduced by some technical bottlenecks. Among those, the uncertainty about the expected durability of the vehicle's onboard battery packs plays a key role in affecting customer choice. In this context, this paper proposes the use of model-based datasets for training a driving support system based on machine learning techniques to be installed on board. The objective of this system is to acquire vehicle, environmental, and traffic information from sensor’ networks and provide real-time smart suggestions to the driver to preserve the remaining useful life of vehicle components, with particular reference to the battery pack and brakes. For the generation of the training dataset, first, a set
Bernardi, Mario LucaCapasso, ClementeIannucci, LuigiSequino, Luigi
A design is presented for an electro-mechanical switchgear, intended for reconfiguring the windings of an electric machine whilst in operation. Specifically, the design is developed for integration onto an in-wheel automotive motor. The motor features 6 phase fractions, which can be reconfigured by the switchgear between series-star or parallel-star arrangements, thereby doubling the torque or speed range of the electric machine. The switchgear has a mass of only 1.8kg – around one tenth of the equivalent 2-speed transmission which might otherwise be employed to achieve a similar effect. As well as the extended operating envelope, the reconfigurable winding motor offers benefits in efficiency and power density. The mechanical solution presented is expected to achieve efficiency and cost advantages over equivalent semiconductor-based solutions, which are practical barriers to adoption in automotive applications. The design uses only mechanical contacts and a single actuator, thereby
Vagg, ChristopherThomas, LukePickering, SimonHerzog, MaticTrinchuk, DanyloRomih, Jaka
Air quality is an increasing concern, particularly in densely populated urban areas. Indeed, large European cities have seen pollutant concentrations exceed World Health Organization thresholds, with a significant portion of NOx emissions originating from road transportation. Studies have shown that less than five percent of the vehicle fleet, often including vehicles with defective after-treatment systems, is responsible for a disproportionate share of these emissions. This highlights the importance of not solely relying on the gradual renewal of vehicle fleets to mitigate health risks associated with air pollution. This research, funded by the French Agency for the Ecological Transition (ADEME), introduces an experimental methodology aimed at controlling emissions from vehicles already in circulation. Aramis Group, a European specialist of refurbishment and online sales of used cars, provided several refurbished used vehicles for testing, directly taken from its workflow. These
Carlos Da Silva, DanielKermani, JosephFarcot, FabriceGaie, Fabien
As electric mobility spreads and evolves, non-exhaust Particulate Matter (PM) sources are gaining more attention for total vehicular emissions. A holistic approach for studying the involved phenomena is necessary to identify the parameters that have the greatest impact on this portion of emissions. To achieve this, it is necessary to develop a new platform capable of both creating testing methodologies for future regulations and enabling the parallel development of advanced tyres and brakes that meet these standards, by correlating vehicle dynamics, driving style, tyre and brake characteristics, and the resulting emissions. Here the authors present the Sustainable Integrated System for Total non-Exhaust Reduction (S.I.S.T.E.R.) project, funded by the Italian Centro Nazionale per la Mobilità Sostenibile (MOST), that aims to develop an integrated approach to study tyre/brake-related emissions from the initial stages of compound development to outdoor vehicle tests, allowing actions to be
Genovese, AndreaDe Robbio, RobertaLenzi, EmanueleCaiazza, AntonioLippiello, FeliceCostagliola, Maria AntoniettaMarchitto, LucaSerra, AntonioArimondi, MarcoBardini, Perla
Advanced technologies that assist the human driver or reduce (or even eliminate) the human driver’s role are becoming increasingly prevalent in new light-duty vehicles used by the general public. These technologies are divided between Active Safety features that monitor the human driver and vehicle motion and act intermittently to mitigate and avoid crashes, and Driving Automation features that assume some or all of the dynamic driving task from the human driver. Both types of technologies have the potential to reduce injuries and save lives by reducing the frequency and/or severity of crashes. Safety Impacts of Active Safety and Driving Automation Features addresses the current capabilities and future potential for Active Safety and Driving Automation features to reduce crash frequency and severity and provides an overview of the state of the industry for both types of features, including current deployments, trends, and anticipated rollouts. Gaps in knowledge, unsettled issues, and
Wishart, Jeffrey
The brake system is a critical safety component in motor vehicles. Advances in the electrification of the powertrain and the rise of autonomous driving technologies are significantly impacting the brake system, which allows innovative approaches and necessitating the development of new brake concepts and new deceleration strategies. A major technological advance is the decoupling of the driver from the brake system through Brake-by-wire technology. A crucial attribute of Brake-by-wire systems is the attainment of a concept-independent deceleration behavior. To establish a consistent and brand-specific deceleration behavior in the early development phase, objective metrics and perceptual thresholds are required to describe the desired subjective braking behavior. Moreover, objective metrics are indispensable for the virtual phase of the vehicle development process. This article focuses on deceleration from a straight-ahead drive. To identify objective metrics and perceptual thresholds
Biller, RalphUdovicic, MatejKetzmerick, ErikKirch, SebastianMayr, StefanProkop, GüntherWagner, Andreas
Steer-by-wire actuators represent a transformative advancement in chassis control, opening up new potential for optimizing driving behavior across the entire range of driving dynamics - including driver-dependent automatic counter steering in critical driving situations. However, from a functional safety perspective, the increased potential also introduces new risks with respect to possible system failures. To mitigate these risks, sophisticated monitoring functions are essential to ensure vehicle controllability at all times. Current research approaches for monitoring functions use safe driving envelopes. This set of safe driving states is often found by open-loop simulations, which provide a phase portrait of the nonlinear system under control and from which stability limits can be derived. However, it remains open how these open-loop stability limits correspond to the stabilization capability of a real human driver in the loop. And secondly, how these closed-loop stability limits
Birkemeyer, JanickNaidu P.M, TarunBorkowski, LukasMüller, Steffen
The optimization and further development of automated driving functions offer significant potential for reducing the driver's workload and increasing road safety. Among these functions, vehicle lateral control plays a critical role, especially with regard to its acceptance by end customers. Significant development efforts are required to ensure the effectiveness and reliability of this aspect in real-world conditions. This work focuses on analyzing lateral vehicle control using extensive measurement data collected from a dedicated vehicle fleet at the Institute of Automotive Engineering at the Technical University of Braunschweig. Equipped with state-of-the-art measurement technology, the fleet has driven several hundred thousand kilometers, allowing for the collection of detailed information on vehicle trajectories under various driving conditions. A total of 93 participants, aged between 20 and 43 years, contributed to the dataset. These measurements have been classified into
Iatropoulos, JannesPanzer, AnnaArntz, MartinPrueggler, AdrianHenze, Roman
Human driver errors, such as distracted driving, inattention, and aggressive driving, are the leading causes of road accidents. Understanding the underlying factors that contribute to these behaviors is critical for improving road safety. Previous studies have shown that physiological states, like raised heart rates due to stress and anxiety, can influence driving behavior, leading to erratic driving and an increased risk of accidents. In this study, we conducted on-road tests using a measurement system based on the Driver-Driven vehicle-Driving environment (3D) method. We collected physiological signals, specially electrocardiography (ECG) data, from human drivers to examine the relationship between physiological states and driving behaviors. The aim was to determine whether ECG can serve as an indicator of potential risky driving behaviors, such as sudden acceleration and frequent steering adjustments. This information enables automated driving (AD) systems to intervene in dangerous
Ji, DejieFlormann, MaximilianBollmann, JulianHenze, RomanDeserno, Thomas M.
The larger size and expanded blind spots of heavy-duty trucks in comparison to passenger cars, create unique challenges for truck drivers navigating narrow roads, such as in urban scenarios. For this reason, the detection of free space around the vehicle is of critical importance, as it has the potential to save lives and reduce operating costs due to less maintenance and downtime. Despite the existence of numerous approaches to free space detection in the literature, few of these have been applied to the trucking sector, disregarding important aspects for these kinds of vehicles such as the altitude at which obstacles are located. This paper aims to present the initial results of our research, a “Not Free Space Warner”, a driving assistance function intended for implementation in series trucks. A methodology is followed to define the characteristics that the perception component of this function shall fulfill. To this end, an analysis of the most critical accidents and common driving
Martinez, CristianPeters, Steven
The article investigates how to detect as quickly as possible whether the driver will lose control of a vehicle, after a disturbance has occurred. Typical disturbances refer to wind gusts, obstacle avoidance, a sudden steer, traversing a pothole, a kick by another vehicle, and so on. The driver may be either human or non-human. Focus will be devoted to human drivers, but the extension to automated or autonomous cars is straightforward. Since the dynamic behavior of vehicle and driver is described by a saddle-type limit cycle, a proper theory is developed to use the limit cycle as a reference trajectory to forecast the loss of control. The Floquet theory has been used to compute a scalar index to forecast stable or unstable motion. The scalar index, named degree of stability (DoS), is computed very early, in the best case, in a few milliseconds after the disturbance has ended. Investigations have been performed at a dynamic driving simulator. A 14 DoF vehicle model, virtually driven by
Della Rossa, FabioFontana, MatteoGiacintucci, SamueleGobbi, MassimilianoMastinu, GiampieroPreviati, Giorgio
Vehicular accident reconstruction is intended to explain the stages of a collision. This also includes the description of the driving trajectories of vehicles. Stored driving data is now often available for accident reconstruction, increasingly including gyroscopic sensor readings. Driving dynamics parameters such as lateral acceleration in various driving situations are already well studied, but angular rates such as those around the yaw axis are little described in the literature. This study attempts to reduce this gap somewhat by evaluating high-frequency measurement data from real, daily driving operations in the field. 813 driving maneuvers, captured by accident data recorders, were analyzed in detail and statistically evaluated. These devices also make it possible to record events without an accident. The key findings show the average yaw rates as a function of driving speed as well as the ratio between mean and associated peak yaw rate. Beyond that, considerably lower yaw rates
Fuerbeth, Uwe
The Equivalent Consumption Minimization Strategy (ECMS) is an effective approach for managing energy flow in hybrid electric vehicles (HEVs), balancing the use of electric energy and fuel consumption. The strategy’s performance depends heavily on the Equivalent Factor (EF), which governs this trade-off. However, the optimal EF varies under different driving conditions and is influenced by the inherent randomness in factors such as traffic, road gradients, and driving behavior, making it challenging to determine through traditional methods. This paper introduces Bayesian Optimization (BO) as a solution to address the stochastic nature of the EF parameter tuning process. By using a probabilistic model, BO efficiently navigates the complex, uncertain performance landscape to find the optimal EF parameters that minimize fuel consumption and emissions across variable conditions. Simulation results under WLTP cycles show that the proposed method reduces fuel consumption by 0.9% and improves
Zhang, CetengfeiZhou, QuanJia, YiqiXiong, Lu
The reliability and performance of steering systems in commercial vehicles are paramount, given their direct impact on reducing hazardous driving and improving operational efficiency. The torque overlay system is designed to enhance driver control, feedback, and reduce driver fatigue. However, vulnerabilities such as water ingress under certain environmental conditions have raised significant reliability requirements. This article discusses the systematic investigation into how radial bearing sideloading led to the input shaft seal failing to contact the input shaft. Water was allowed a path to enter the TOS module, affecting the electronic sensor, and faulting out the ADAS functionality. Improvement to the bearing support and sealing design culminated to an enhanced TOS module package able to withstand testing procedures that mimic the environmental and use case situation which caused the ingress.
Bari, Praful RajendraKintner, Jason
This SAE Recommended Practice is intended to establish a procedure to certify the fundamental driving skill levels of professional drivers. This certification can be used by the individual driver to qualify their skills when seeking employment or other professional activity. These certification levels may also be used by test facilities or other organizations when seeking test or professional drivers of various skills. The associated family of documents listed below establish driving skill criteria for various specific categories. SAE J3300: Driving level SAE J3300/1: Low mu/winter driving SAE J3300/2: Trailer towing SAE J3300/3: Automated driving Additional certifications to be added as appropriate. This main document provides: (1) common definitions and general guidance for using this family of documents, (2) directions for obtaining certification through Probitas Authentication®1, and (3) driving level examination requirements.
Driving Skills Standards Committee
The existing variable speed limit (VSL) control strategies rely on variable message signs, leading to slow response times and sensitivity to driver compliance. These methods struggle to adapt to environments where both connected automated vehicles (CAVs) and manual vehicles coexist. This article proposes a VSL control strategy using the deep deterministic policy gradient (DDPG) algorithm to optimize travel time, reduce collision risks, and minimize energy consumption. The algorithm leverages real-time traffic data and prior speed limits to generate new control actions. A reward function is designed within a DDPG-based actor-critic framework to determine optimal speed limits. The proposed strategy was tested in two scenarios and compared against no-control, rule-based control, and DDQN-based control methods. The simulation results indicate that the proposed control strategy outperforms existing approaches in terms of improving TTS (total time spent), enhancing the throughput efficiency
Ding, XibinZhang, ZhaoleiLiu, ZhizhenTang, Feng
In addition to providing safety advantages, sound and vibration are being utilized to enhance the driver experience in Battery Electric Vehicles (BEVs). There's growing interest and investment in using both interior and exterior sounds for pedestrian safety, driver awareness, and unique brand recognition. Several automakers are also using audio to simulate virtual gear shifting of automatic and manual transmissions in BEVs. According to several automotive industry articles and market research, the audio enhancements alone, without the vibration that drivers are accustomed to when operating combustion engine vehicles, are not sufficient to meet the engagement, excitement, and emotion that driving enthusiasts expect. In this paper, we introduce the use of new automotive, high-force, compact, light-weight circular force generators for providing the vibration element that is lacking in BEVs. The technology was developed originally for vibration reduction/control in aerospace applications
Norris, Mark A.Orzechowski, JeffreySanderson, BradSwanson, DouglasVantimmeren, Andrew
Subjective perception of vehicle secondary ride is dependent on simultaneous touchpoint vibrations and audible inputs to the occupants. Standards such as ISO 2361 provide guidelines for objective assessments of human body thresholds to vibration [1]. However, when a human experiences vibration inputs at multiple touchpoints, as well as aural inputs, it becomes complicated to judge each individual contribution to the overall subjective perception [2]. Additional factors, such as ambient conditions, ergonomics, age, gender etc. also play a role. Secondary ride, which is defined as energy in the 10-30 Hz frequency range, is one such event that affects the customers’ perception of ride comfort and quality. The goal of this work is to develop a sound and vibration simulator model and execute a secondary ride jury study of vehicle driving over cleats. The aim of the study is to rank the contributions of each touch point vibration input, as well as sound to the overall subjective perception
Jayakumar, VigneshJoodi, BenjaminGeissler, ChristianPilz, FernandoLynch, LukeConklin, ChrisWeilnau, KelbyHodgkins, Jeffrey
The implementation of active sound design models in vehicles requires precise tuning of synthetic sounds to harmonize with existing interior noise, driving conditions, and driver preferences. This tuning process is often time-consuming and intricate, especially facing various driving styles and preferences of target customers. Incorporating user feedback into the tuning process of Electric Vehicle Sound Enhancement (EVSE) offers a solution. A user-focused empirical test drive approach can be assessed, providing a comprehensive understanding of the EVSE characteristics and highlighting areas for improvement. Although effective, the process includes many manual tasks, such as transcribing driver comments, classifying feedback, and identifying clusters. By integrating driving simulator technology to the test drive assessment method and employing machine learning algorithms for evaluation, the EVSE workflow can be more seamlessly integrated. But do the simulated test drive results
Hank, StefanKamp, FabianGomes Lobato, Thiago Henrique
Sound power is a commonly used metric to quantify acoustic sources like AC motor in electrified powertrain. Testing for sound power determination is often performed in an anechoic environment to create free-field conditions around the unit. To eliminate the influence of extraneous noise sources, the anechoic facilities must be further isolated from driver and absorber dynamometers. These dynamometers are needed for running the AC motors in the desired speed and load conditions. For early detection of potential issues, it is advantageous to have the capability for engineers to conduct acoustic tests in standard laboratory environments. These may include non-acoustically treated rooms, presence of extraneous noise sources (e.g., driver and absorber dynos), etc. In such environments, sound intensity-based sound power determination methods could be utilized. The sound intensity-based approach is covered in ISO 9614 standard. The norm is to sweep an intensity probe on a sound source in
Kumar, AdityaIppili, Rajani
As the automotive industry moves toward electrification, new challenges emerge in keeping pleasant acoustics inside vehicles and their surroundings. This paper proposes a method for anticipating the main sound sources at driver’s ear for custom driving scenarios. Different categories of Road and Wind noise were created from a dataset of multiple vehicles. Using innovative sound synthesis techniques, it enables Valeo to make early predictions of the emergence of an electric axle powertrain (ePWT) once it is combined with this masking noise. Realistic signals could be generated and compared with actual acoustic measurements to validate the method.
Redon, MilanDendievel, ClementPluton, Matthias
The frequency and amplitude content of powertrain noise is motor torque and speed dependent and tends to influence the driver’s subjective perception of the vehicle. This provides manufacturers with an opportunity to drive product differentiation through consideration of powertrain noise in early stages of the development cycles for electric vehicles (EVs). This paper focuses on the evaluation of customer preference and perception of acoustic feedback from different powertrain design options based on targeted powertrain orders and expected wind and road masking during high acceleration maneuvers. A jury study is used to explore customer feedback to a two-stage gearbox design with AC permanent magnet motor order combinations. The subjective influence of order spacing, dominant frequency content and the number of audible orders is studied to understand aural perspective product differentiation opportunities.
Joodi, BenjaminJayakumar, VigneshConklin, ChrisPilz, FernandoIyengar, ShashankWeilnau, KelbyHodgkins, Jeffrey
Silent motors are an excellent strategy to combat noise pollution. Still, they can pose risks for pedestrians who rely on auditory cues for safety and reduce driver awareness due to the absence of the familiar sounds of combustion engines. Sound design for silent motors not only tackles the above issues but goes beyond safety standards towards a user-centered approach by considering how users perceive and interpret sounds. This paper examines the evolving field of sound design for electric vehicles (EVs), focusing on Acoustic Vehicle Alerting Systems (AVAS). The study analyzes existing AVAS, classifying them into different groups according to their design characteristics, from technical concerns and approaches to aesthetic properties. Based on the proposed classification, an (adaptive) sound design methodology, and concept for AVAS are proposed based on state-of-the-art technologies and tools (APIs), like Wwise Automotive, and integration through a functional prototype within a virtual
Rodrigues Ferraz Esteves, Ana RaquelCampos Magalhães, Eduardo MiguelBernardes de Almeida, Gilberto
With the advancement of control technology in the automotive field, there is a possibility of cross-system redundant control between various actuators. As for the braking system, current brake-by-wire system often uses mechanical backup braking methods to give the vehicle a certain braking capacity after failure. However, in the mechanical backup braking mode, the brake master cylinder is connected to the supporting wheel cylinder, and the brake assist is lost, which leads to an increase in brake pressure and makes it difficult for the driver to step on the brake pedal. Meanwhile, due to the limitation of the brake master cylinder stroke, the maximum braking deceleration of the vehicle is only 3 m/s2 after the driver fully presses the brake pedal. The above two defects greatly affect the safety of the vehicle during backup braking. To solve the above problems, this article takes electric vehicles as the research object, designs a new type of hydraulic circuit for the braking system
Tian, BoshiLi, LiangLiao, YinshengLv, HaijunHu, ZhimingSun, YueQu, Wenying
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
These general operator precautions apply to off-road work machines as defined in SAE J1116. These should not be considered as all-inclusive for all specific uses and unique features of each particular machine. Other more specific operator precautions not mentioned herein should be covered by users of this recommended practice for each particular machine application.
OPTC1, Personnel Protection (General)
This practice presents methods for establishing the driver workspace. Methods are presented for: Establishing accelerator reference points, including the equation for calculating the shoe plane angle Locating the SgRP as a function of seat height (H30) Establishing seat track dimensions using the seating accommodation model Establishing a steering wheel position Application of this document is limited to Class-A Vehicles (Passenger Cars, Multipurpose Passenger Vehicles, and Light Trucks) as defined in SAE J1100.
Human Accom and Design Devices Stds Comm
Drivers sometimes operate the accelerator pedal instead of the brake pedal due to driver error, which can potentially result in serious accidents. To address this, the Acceleration Control for Pedal Error (ACPE) system has been developed. This system detects such errors and controls vehicle acceleration to prevent these incidents. The United Nations is already considering regulations for this technology. This ACPE system is designed to operate at low speeds, from vehicle standstill to creep driving. However, if the system can detect errors based on the driver's operation of the accelerator pedal at various driving speeds, the system will be even more effective in terms of safety. The activation threshold of ACPE is designed to detect operational errors, and it is necessary to prevent the system from being activated during operational operations other than operational errors, i.e., false activation. This study focuses on the pedal operation characteristics of pedal stroke speed and
Natsume, HayatoShen, ShuncongHirose, Toshiya
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
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
Predictive performance simulation of a high-efficiency lightweight vehicle is performed through development of a multi-physics MATLAB Simulink model including advanced vehicle dynamics. The vehicle is put into a three-dimensional representation of the racetrack, including its dimensions, slope, banking, and adhesion coefficient along the model space, elaborated from the track GPS data points. The vehicle’s reference trajectory is not priorly provided to the model at the simulation start as, during run-time, a predictive Steering Angle Generation (SAG) algorithm based on Nonlinear Model Predictive Control (NMPC) computes the optimal steering angle input needed to drive the vehicle on the track within its limits. Computation is based on fast predictive simulations of a simplified version of dynamics modelling of the vehicle. Each single simulation exploits a different possible steering angle to be applied by the virtual driver, starting from the initial conditions given by the actual
De Carlo, MatteoManzone, Simonede Carvalho Pinheiro, HenriqueCarello, Massimiliana
As a distributed wire control brake system, the electro-mechanical brake (EMB) may face challenges due to the need to integrate the actuator in the limited space beside the wheel. During extended downhill braking, especially on wet roads with reduced adhesion, the EMB must operate at high intensity. The significant heat generated by friction can lead to thermal deformation of components, such as the lead screw, compromising braking stability. This paper focuses on pure electric light trucks and proposes a tandem composite braking method. This approach uses an eddy current retarder (ECR) or motor to provide basic braking torque, while the EMB supplies the dynamic portion of the braking torque, thereby alleviating the braking pressure on the EMB. First, a driver model, tire model, motor model, and braking models are developed based on the vehicle's longitudinal dynamics. In addition, the impact of various factors, such as rainfall intensity, road slope, ramp length and vehicle speed, on
Liu, WangZhang, YuXiao, HongbiaoShen, Leiming
Steering feeling plays a critical role in the driving experience and is one of the most significant topics during a new vehicle development process. To reach a consensus for the customers’ satisfaction in both the subjective and objective characteristics in a particular market segment, there have been several studies to investigate the correlations between subjective and objective evaluations of on-center steering feeling. However, it is still not clear how to determine the steering characteristic based on the correlations. In this paper, a series of new correlations between subjective and objective evaluations are built, which focus on steering stiffness, on-center feel, torque symmetry, torque ripple etc. Firstly, a set of objective metrics which are followed by professional test drivers or tuning experts have been extracted from 12 vehicles’ on-center handling test based on ISO 13674-1 2023, these vehicles covering different motorcycle type, various brands and diverse tuning styles
Jin, AnkangLuo, KaijieYang, JianyuanZheng, Yue
FSAE is a competition designed to maximize car performance, in which the steering system is a key subsystem, and the steering system performance directly affects the cornering performance of the car. The driver relies on the steering system for effective handling, which is also crucial for cornering and achieving faster lap times. Therefore, while improving the performance of the steering system, it is crucial to match the vehicle design to the driver's habits. Traditionally, steering systems typically use an Ackermann rate between 0% and 100% to offset the slip angle caused by tire deformation, thus achieving the purpose of reducing tire wear. Calculations have shown that a 40-60% Ackermann rate provides a similar compensation effect with little difference in tire wear. The traditional steering design method also does not consider the driver's driving habits and feedback, which is not conducive to the improvement of the overall performance of the car. In FSAE's figure-of-eight loops
Wu, HailinLi, Mingyuan
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