Browse Topic: Vehicle dynamics

Items (8,418)
The wheel hub motor–driven electric vehicle, characterized by its independently controllable wheels, exhibits high torque output at low speeds and superior dynamic response performance, enabling in-place steering capabilities. This study focuses on the control mechanism and dynamic model of the wheel hub motor vehicle’s in-place steering. By employing differential torque control, it generates the yaw moment needed to overcome steering resistance and produce yaw motion around the steering center. First, the dynamic model for in-place steering is established, exploring the various stages of tire motion and the steering process, including the start-up, elastic deformation, lateral slip, and steady-state yaw. In terms of control strategy, an adaptive in-place steering control method is designed, utilizing a BP neural network combined with a PID control algorithm to track the desired yaw rate. Additionally, a control strategy based on tire/road adhesion ellipse theory is developed to
Huang, BinCui, KangyuZhang, ZeyangMa, Minrui
In traditional four-wheeled automobiles, the imbalance between the roll moment, which is the product of the centrifugal force during a turn acting on the center of gravity and the height of the center of gravity, and roll stiffness, which is the product of the left-right difference in tire vertical load and the tread width and commonly used among automotive suspension engineers, of the front and rear sections necessitates body torsional rigidity. However, there is a lack of specific cases and guidelines for constructing the body structure of three-wheeled PMVs (Personal Mobility Vehicles) with a tilting mechanism from the perspective of vehicle dynamics characteristics. In this paper, the basic considerations related to the dynamics of such three-wheeled PMVs are investigated. We use the term “torsional rigidity” to refer to the stiffness as the torsional deformation of the body itself, and the term “roll stiffness” to refer to the moment that counteracts the roll moment during a turn
Haraguchi, TetsunoriKaneko, Tetsuya
Off-road vehicle demand is on the rise, particularly in North America. In connection with this trend, there is a demand for dynamic modeling to describe the behavior of off-road vehicles when driving terrains surfaces with successive bumps. However, conventional dynamic models has been insufficient in representing the situation where the tire-ground contact and detachment states switch successively during whoops behavior. Therefore, in this study, rigid-body multibody dynamics methodology was employed to model the vehicle and conduct numerical simulations. Numerical simulations were conducted using the constructed vehicle model, demonstrating that the behavior of off-road vehicles in whoops closely resembles the actual phenomenon.
Inoue, TsuyoshiEjiri, HarutoHeya, AkiraYoshida, Masahiro
In this study, vibration characteristics inside an electric power unit at gravity center where direct measurement is impossible were estimated by using virtual point transformation to consider guideline for effective countermeasures to the structure or generated force characteristics inside the power source. Vibration acceleration, transfer function and the generated force in operation at the gravity center of the electrical power source were obtained by vibration characteristics at around the power source which can be measured directly. In addition, the transfer functions from the gravity center to the power source attachment points on the product were also estimated. And then, the contribution from the gravity center to the power unit attachment point was obtained by multiplying generated force with the transfer function. As results, the obtained total contribution was almost same with the actual measured vibration at the attachment point. Furthermore, the rotational contribution
Kubo, RyomaHara, KentaYoshida, Junji
The possibilities and challenges of adding a rider model to the motorcycle dynamics simulation were investigated for the future planning of a full virtual test. The human model was added to a multi-body dynamics model that reproduces the equations of motion of a motorcycle, called the 10 degrees of freedom (10-DoF) model. The human model is composed from multiple masses and joints, and the steering angle can be controlled by determining the angle of the arms and shoulder. To study the effect of this model, three distinct simulations were carried out: ‘the eigenvalue analysis’, ‘the steady-state circular test simulation’ and ‘the slalom running simulation’. In the eigenvalue analysis, the eigenvalues of the wobble mode shifted to a stable side in the root locus when both hands were fixed on the handlebars. As a result of the slalom running simulation, the response of the handlebar control through the human model produced a more convex trajectory than a direct control of the steering
Ueki, MotohitoTakayama, AkihiroYabe, Noboru
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
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
Contemporary Japanese society relies heavily on vehicles for transportation and leisure. This has led to environmental concerns owing to vehicle emissions, prompting a shift toward environmentally friendly alternatives, such as clean diesel and electric vehicles. Clean diesel vehicles aim to reduce harmful emissions, whereas electric vehicles are favored because of their minimal emissions and quiet operation. However, the lack of engine noise in electric vehicles can make it difficult for drivers to perceive speed changes, potentially increasing the risk of accidents, and simply amplifying all sounds is not viable because it may cause discomfort. Therefore, this study explored how deviations from expected engine sounds affect the perceived sound quality and vehicle performance assessment. Unlike traditional gasoline-powered and clean diesel vehicles, electric vehicles produce very little running noise, which makes road surface noise more prominent. Given the novelty of electric
Nitta, MisakiIshimitsu, ShunsukeFujikawa, SatoshiIwata, KiyoakiNiimi, MayukoKikuchi, MasakazuMatsumoto, Mitsunori
TOC
Tobolski, Sue
This recommended practice defines methods for the measurement of periodic, random and transient whole-body vibration. It indicates the principal factors that combine to determine the degree to which a vibration exposure will cause discomfort. Informative appendices indicate the current state of knowledge and provide guidance on the possible effects of motion and vibration on discomfort. The frequency range considered is 0.5 Hz to 80 Hz. This recommended practice also defines the principles of preferred methods of mounting transducers for determining human exposure. This recommended practice is applicable to light passenger vehicles (e.g., passenger cars and light trucks). This recommended practice is applicable to motions transmitted to the human body as a whole through the buttocks, back and feet of a seated occupant, as well as through the hands of a driver. This recommended practice offers a method for developing a ride performance index but does not specifically describe how to
Vehicle Dynamics Standards Committee
Automotive signal processing is dealt with in several contributions that propose various techniques to make the most out of the available data, typically for enhancing safety, comfort, or performance. Specifically, the accurate estimation of tire–road interaction forces is of high interest in the automotive world. A few years ago the T.R.I.C.K. tool was developed, featuring a vehicle model processing experimental data, collected through various vehicle sensors, to compute several relevant virtual telemetry channels, including interaction forces and slip indices. Following years of further development in collaboration with motorsport companies, this article presents T.R.I.C.K. 2.0, a thoroughly renewed version of the tool. Besides a number of important improvements of the original tool, including, e.g., the effect of the limited slip differential, T.R.I.C.K. 2.0 features the ability to exploit advanced sensors typically used in motorsport, including laser sensors, potentiometers, and
Napolitano Dell’Annunziata, GuidoFarroni, FlavioTimpone, FrancescoLenzo, Basilio
Amphibious vehicles are widely used in civil and military scenarios due to their excellent driving performance in water and on land, unique application scenarios and rapid response capabilities. In the field of civil rescue, the hydrodynamic performance of amphibious vehicles directly affects the speed and accuracy of rescue, and is also related to the life safety of rescuers. In the existing research on the hydrodynamic performance of amphibious vehicles, seakeeping performance has always been the focus of research by researchers and amphibious vehicle manufacturers, but most of the existing research focuses on the navigation performance of amphibious vehicles in still water. In actual application scenarios, amphibious vehicles often face complex water conditions when performing emergency rescue tasks, so it is very important to study the navigation performance of amphibious vehicles in waves. Aiming at the goal of studying the navigation performance of amphibious vehicles in waves
Zhang, Yu
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
With the increasing prevalence of electric vehicles (EVs), decreasing vehicle drag is of upmost importance, as range is a primary consideration for customers and has a direct bearing on the cost of the vehicle. While the relationship between drag and range is well understood, there exists a discrepancy between the label range and the real-world range experienced by customers. One of the factors influencing the difference is the ambient wind condition that modifies the resultant air speed and yaw angle, which is typically minimized during SAE coast-down testing. The following study implements a singular wind-averaged drag (WAD) coefficient which is derived from a 3-point yaw curve to show the impact of yaw as compared to the zero-yaw condition. This leads to an interesting dilemma for the vehicle aerodynamicist: whether to optimize the vehicle's exterior shape for low wind (zero yaw) conditions or for real-world conditions where the ambient wind generally produces a few degrees of yaw
Kaminski, MeghanD'Hooge, AndrewBorton, Zackery
The natural wind experienced on public roads can increase the yaw angle and therefore drag coefficient (CD), which may contribute to the discrepancy between catalog fuel economy and actual fuel economy. The impact of yaw characteristics alone on fuel economy during actual driving has not been verified or proven as it is difficult to obtain actual driving data under uniform conditions. For this reason, shape optimization is normally performed at zero-yaw through the aerodynamic development phases. In this paper, two vehicles with different yaw sensitivity characteristics are driven simultaneously, and fuel economy measurements are performed simultaneously with ambient airflow, environment, and vehicle conditions. The results where the conditions of the two vehicles match are extracted to clarify the impact of the differences of yaw characteristics on fuel economy. The obtained results matched the values predicted by theoretical calculations for the impact of yaw angle on fuel economy
Onishi, YasuyukiNichols, LarryMetka, Mattmasumitsu, YasutakaInoue, Taisuke
Novel experimental and analytical methods were developed with the objective of improving the reliability and repeatability of coast-down test results. The methods were applied to coast-down tests of a SUV and a tractor-trailer combination, for which aerodynamic wind-tunnel data were available for comparison. The rationale was to minimize the number of unknowns in the equation of motion by measuring rolling and mechanical resistances and wheel-axle moments of inertia, which was achieved using novel experimental techniques and conventional rotating-drum tests. This led to new modelling functions for the rolling and mechanical resistances in the equation of motion, which was solved by regression analysis. The resulting aerodynamic drag coefficient was closer to its wind-tunnel counterpart, and the predicted low-speed road load was closer to direct measurements, than the results obtained using conventional methods. It is anticipated that applying the novel techniques to characterize the
Tanguay, Bernardde Souza, Fenella
In order to effectively improve the chassis handling stability and driving safety of intelligent electric vehicles (IEVs), especially in combing nonlinear observer and chassis control for improving road handling. Simultaneously, uncertainty with system input, are always existing, e.g., variable control boundary, varying road input or control parameters. Due to the higher fatality rate caused by variable factors, how to precisely chose and enforce the reasonable chassis prescribed performance control strategy of IEVs become a hot topic in both academia and industry. To issue the above mentioned, a fuzzy sliding mode control method based on phase plane stability domain is proposed to enhance the vehicle’s chassis performance during complex driving scenarios. Firstly, a two-degree-of-freedom vehicle dynamics model, accounting for tire non-linearity, was established. Secondly, combing with phase plane theory, the stability domain boundary of vehicle yaw rate and side-slip phase plane based
Liao, YinshengWang, ZhenfengGuo, FenghuanDeng, WeiliZhang, ZhijieZhao, BinggenZhao, Gaoming
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
Due to the frequent and significant changes of the motor torque of hybrid vehicles during driving often occurring with the driving conditions, and the existence of the transmission tooth surface switching caused by the change in torque direction, as well as the underdamping characteristics caused by the relatively simple transmission system, the vehicle is prone to vehicle body shaking problems under conditions such as the transformation from acceleration conditions to energy recovery conditions, and exit from energy recovery. In order to ensure the ride smoothness of the hybrid vehicle while improving its power response performance, aiming at the underdamping characteristics of its transmission system, this paper develops a transmission PCM vibration suppression control strategy based on the vehicle control system to enhance the torque response and smoothness after Tip out or Tip in after braking. This strategy includes the identification of preconditions and the active intervention
Jing, JunchaoZhang, JunzhiZuo, BotaoLiu, YiqiangHuang, WeishanXue, Tianjian
With the continuous development of automobile technology, vehicle handling performance and safety have become increasingly critical research areas. The active rear-wheel (ARW) steering system, a technology that significantly enhances vehicle dynamics and driving stability, has garnered widespread attention. By coordinating front-wheel steering with rear-wheel angle adjustments, ARW improves handling flexibility and stability, particularly during high-speed driving and under extreme conditions. Therefore, designing an efficient ARW control algorithm and optimizing its performance are vital to enhancing a vehicle's overall handling capability. This study delves into the control algorithm design and performance optimization of ARW. First, a comprehensive vehicle dynamics model is constructed to provide a solid theoretical basis for developing control algorithms. Next, optimal control theory is applied to regulate the rear-wheel steering angle, and an LQR control strategy with variable
Zhang, YiZheng, HongyuKaku, ChuyoZong, ChangfuZhang, Yuzhou
Sled crash tests are an important tool to develop automotive restraint systems. Compared with full-scale crash tests, the sled test has a shorter development cycle of the restraint system and lower cost. The objective of the present study is to create a cost-effective sled test methodology, calculate the optimal static yaw angle and loading curves, and analyze the motion response and injuries of the dummy in the small overlap crash test. The effectiveness of the proposed methodology was verified under two typical small overlap frontal crash modes: “energy-absorption” and “sideswipe”. The results show that with the calculated yaw angle α, the HIC was different from the small overlap crash model, but all remaining indices were within 5% of the injury criteria. All International Organization for Standardization (ISO) values between the combined accelerations of all parts of the dummy and those of the basic model exceeded 0.75, and some values were above 0.8. Therefore, the proposed sled
Yu, LiuChen, JianzhuoWan, Ming XinFan, TiqiangYang, PeilongNie, ZhenlongRen, LihaiCheng, James Chih
Vehicle handling is significantly influenced by aerodynamic forces, which alter the normal load distribution across all four wheels, affecting vehicle stability. These forces, including lift, drag, and side forces, cause complex weight transfers and vary non-linearly with vehicle apparent velocity and orientation relative to wind direction. In this study, we simulate the vehicle traveling on a circular path with constant steering input, calculate the normal load on each tire using a weight transfer formula, calculate the effect of lift force on the vehicle on the front and rear, and calculate the vehicle dynamic relation at steady state because the frequency of change due to aerodynamic load is significantly less than that of the yaw rate response. The wind velocity vector is constant while the vehicle drives in a circle, so the apparent wind velocity relative to the car is cyclical. Our approach focuses on the interaction between two fundamental non-linearity’s: the nonlinear
Patil, HarshvardhanWilliams, Daniel
With the increasing prevalence of Automatic Emergency Braking Systems (AEB) in vehicles, their performance in actual collision accidents has garnered increasing attention. In the context of AEB systems, the pitch angle of a vehicle can significantly alter the nature of collisions with pedestrians. Typically, during such collisions, the pedestrian's legs are the first to come into contact with the vehicle's front structure, leading to a noticeable change in the point of impact. Thus, to investigate the differences in leg injuries to pedestrians under various pitch angles of vehicles when AEB is activated, this study employs the Total Human Model for Safety (THUMS) pedestrian finite element model, sensors were established at the leg location based on the Advanced Pedestrian Legform Impactor (APLI), and a corresponding vehicle finite element model was used for simulation, analyzing the dynamic responses of the pedestrian finite element model at different pitch angles for sedan and Sport
Hong, ChengYe, BinZhan, ZhenfeiLiu, YuWan, XinmingHao, Haizhou
Hybrid vehicles are driven by the vehicle controller, engine controller and motor controller through torque control, and there may be unexpected acceleration or deceleration of the vehicle beyond the driver's expectation due to systematic failure and random hardware failure. Based on the torque control strategy of hybrid vehicles, the safety monitoring model design of torque control is carried out according to the ISO 26262 safety analysis method. Through the establishment of safety goals and the analysis of safety concepts, this paper conducts designs including the driver allowable torque design for safety monitoring, the driver torque prediction design for safety monitoring, the rationality judgment design of driver torque for safety monitoring, the functional safety degradation design, and the engine start-stop status monitoring, enabling the system to transition to a safe state when errors occur. Firstly, the design of the driver's allowable torque includes the allowable requested
Jing, JunchaoWang, RuiguangLiu, YiqiangHuang, WeishanDai, Zhengxing
This paper is a continuation of a previous effort to evaluate the post-impact motion of vehicles with high rotational velocity within various vehicle dynamic simulation softwares. To complete this goal, this paper utilizes a design of experiments (DOE) method. The previous papers analyzed four vehicle dynamic simulation software programs; HVE (SIMON and EDSMAC4), PC-Crash and VCRware, and applied the DOE to determine the most sensitive factors present in each simulation software. This paper will include Virtual Crash into this methodology to better understand the significant variables present within this simulation model. This paper will follow a similar DOE to that which was conducted in the previous paper. A total of 32 trials were conducted which analyzed ten factors. Aerodynamics, a factor included in the previous DOE, was not included within this DOE because it does not exist within Virtual Crash. The same three response variables from the previous DOE were measured to determine
Roberts, JuliusCivitanova, NicholasStegemann, JacobBuzdygon, DavidThobe, Keith
Accurate reconstruction of vehicle collisions is essential for understanding incident dynamics and informing safety improvements. Traditionally, vehicle speed from dashcam footage has been approximated by estimating the time duration and distance traveled as the vehicle passes between reference objects. This method limits the resolution of the speed profile to an average speed over given intervals and reduces the ability to determine moments of acceleration or deceleration. A more detailed speed profile can be calculated by solving for the vehicle’s position in each video frame; however, this method is time-consuming and can introduce spatial and temporal error and is often constrained by the availability of external trackable features in the surrounding environment. Motion tracking software, widely used in the visual effects industry to track camera positions, has been adopted by some collision reconstructionists for determining vehicle speed from video. This study examines the
Perera, NishanGriffiths, HarrisonPrentice, Greg
Videos from cameras onboard a moving vehicle are increasingly available to collision reconstructionists. The goal of this study was to evaluate the accuracy of speeds, decelerations, and brake onset times calculated from onboard dash cameras (“dashcams”) using a match-moving technique. We equipped a single test vehicle with 5 commercially available dashcams, a 5th wheel, and a brake pedal switch to synchronize the cameras and 5th wheel. The 5th wheel data served as the reference for the vehicle kinematics. We conducted 9 tests involving a constant-speed approach (mean ± standard deviation = 57.6 ± 2.0 km/h) followed by hard braking (0.989 g ± 0.021 g). For each camera and brake test, we extracted the video and calculated the camera’s position in each frame using SynthEyes, a 3D motion tracking and video analysis program. Scale and location for the analyses were based on a 3D laser scan of the test site. From each camera’s position data, we calculated its speed before braking and its
Flynn, ThomasAhrens, MatthewYoung, ColeSiegmund, Gunter P.
A rule-based unilateral fault-tolerant control strategy is proposed to improve the vehicle's yaw stability and dynamics in case of drive system failure for multi-axle differential steering vehicles due to various unpredictable factors during driving. Meanwhile, based on the conditional integration algorithm, a multi-axis differential steering vehicle dynamics control is designed to resist integration saturation, which ensures that the vehicle tracks the reference signal accurately. In order to test the designed fault-tolerant control strategy, the first wheel drive motor in the left is set to be in a state of complete failure after the 10th second on the basis of the vehicle's forward-steering driving condition in order to construct a failure test condition; deviation angle error without fault-tolerant control is 0.22182rad and the extreme value of the yaw velocity error is 0.03687 rad/s. After fault-tolerant control, the extreme value of the center-of-mass lateral deviation angle
Zou, MingyuLu, JunZeng, DequanYu, YinquanYang, JinwenHu, YimingYu, QinWang, Xiaoliang
The Distributed Drive Electric Vehicles (DDEVs) offer advantages such as independently controllable driving and braking forces at each wheel, rapid response, and precise control. These features enable effective electronic stability control (ESC) by appropriately distributing torque across each wheel. However, traditional ESC systems typically employ single-wheel hydraulic differential braking, failing to fully utilize the independent torque control capabilities of DDEVs. This study proposes a hierarchical control strategy for distributed driving and braking ESC based on particle filter (PF) and fuzzy integral sliding mode control (FISMC). First, the vehicle state estimation layer uses a three-degree-of-freedom vehicle model and the PF to estimate sideslip angle and vehicle speed. Next, the target torque decision layer includes a target speed tracking controller and a yaw moment decision controller. The yaw moment decision controller uses the FISMC to determine additional yaw moment by
Li, XiaolongZheng, HongyuKaku, Chuyo
Vehicle sideslip is a valuable measurement for ground vehicles in both passenger vehicle and racing contexts. At relevant speeds, the total vehicle sideslip, beta, can help drivers and engineers know how close to the limits of yaw stability a vehicle is during the driving maneuver. For production vehicles or racing contexts, this measurement can trigger Electronic Stability Control (ESC). For racing contexts, the method can be used for driver training to compare driver techniques and vehicle cornering performance. In a fleet context with Connected and Autonomous Vehicles (CAVS) any vehicle telemetry reporting large vehicle sideslip can indicate an emergency scenario. Traditionally, sideslip estimation methods involve expensive and complex sensors, often including precise inertial measurement units (IMUs) and dead reckoning, plus complicated sensor fusion techniques. Standard GPS measurements can provide Course Over Ground (COG) with quite high accuracy and, surprisingly, the most
Hannah, AndrewCompere, Marc
Since most of the existing studies focus on the identification of the yaw stable region, but ignore the identification of the roll stable region, this article presents a software tool YRSRA for calculating both the yaw and roll stable region for ground vehicle system with 5G-V2X. And the frequency of rollover instability of commercial vehicles such as trucks and buses is not low, and the cost of rollover accidents is often greater than the cost of yaw instability accidents. Therefore, it is necessary to identify the stability region of yaw and roll at the same time. Firstly, the iterative model of yaw rate and slip angle is constructed through deducing the two-degree-of-freedom vehicle dynamics. Secondly, the load transfer ratio (LTR) is coded with given yaw rate and slip angle. Thirdly, several Illustrative examples are depicted, such as variation of steer angle, road adhesion coefficient and vehicle speed. The software features an easy to generate yaw and roll stability region by on
Tu, LihongZeng, DequanZhang, ZhoupingHe, QixiaoZhao, ShuqiSun, JingWang, AichunYu, QinMing, JinghongWang, XiaoliangHu, Yiming
In cost- effective P2 hybrid vehicles with low voltage electric machines connected to the engine, an interesting control problem arises during the transition to a locked driveline state. This occurs when the engine connects to the wheels via a separation clutch. The two primary torque sources, the engine and the clutch, are traditionally imperfect estimators of applied and transferred torques. The Hybrid Supervisor’s feedforward constraints model relies on these imperfect inputs to determine torque and acceleration limits for the engine’s desired acceleration profiles and to specify engine feedforward commands, aiming for synchronization speed. Due to the inaccuracies in the torque estimates of the engine and clutch, the Hybrid Supervisor is susceptible to control windup, increased jerk to the driveline during synchronization, and inaccurate computation of its target acceleration profile, speed, and torque targets for the engine to achieve synchronization speed. This paper presents a
Banuso, AbdulquadriSha, HangxingKarogal, IndrasenMadireddy, Krishna ChaitanyaPatel, Nadirsh
This study evaluates the performance of alternative powertrains for Class 8 heavy-duty trucks under various real-world driving conditions, cargo loads, and operating ranges. Energy consumption, greenhouse gas emissions, and the Levelized Cost of Driving (LCOD) were assessed for different powertrain technologies in 2024, 2035, and 2050, considering anticipated technological advancements. The analysis employed simulation models that accurately reflect vehicle dynamics, powertrain components, and energy storage systems, leveraging real-world driving data. An integrated simulation workflow was implemented using Argonne National Laboratory's POLARIS, SVTrip, Autonomie, and TechScape software. Additionally, a sensitivity analysis was performed to assess how fluctuations in energy and fuel costs impact the cost-effectiveness of various powertrain options. By 2035, battery electric trucks (BEVs) demonstrate strong cost competitiveness in the 0-250 mile and 250-500 mile ranges, especially when
Mansour, CharbelBou Gebrael, JulienKancharla, AmarendraFreyermuth, VincentIslam, Ehsan SabriVijayagopal, RamSahin, OlcayZuniga, NataliaNieto Prada, DanielaAlhajjar, MichelRousseau, AymericBorhan, HoseinaliEl Ganaoui-Mourlan, Ouafae
The unicycle self-balancing mobility system offers superior maneuverability and flexibility due to its unique single-wheel grounding feature, which allows it to autonomously perform exploration and delivery tasks in narrow and rough terrains. In this paper, a unicycle self-balancing robot traveling on the lunar terrain is proposed for autonomous exploration on the lunar surface. First, a multi-body dynamics model of the robot is derived based on quasi-Hamilton equations. A three-dimensional terramechancis model is used to describe the interaction between the robot wheels and the lunar soil. To achieve stable control of the robot's attitude, series PID controllers are used for pitch and roll attitude self-balancing control as well as velocity control. The whole robot model and control strategy were built in MATLAB and the robot's traveling stability was analyzed on the lunar terrain.
Shi, JunweiZhang, KaidiDuan, YupengWu, JinglaiZhang, Yunqing
One challenge for autonomous vehicle (AV) control is the variation in road roughness which can lead to deviations from the intended course or loss of road contact while steering. The aim of this work is to develop a real-time road roughness estimation system using a Bayesian-based calibration routine that takes in axle accelerations from the vehicle and predicts the current road roughness of the terrain. The Bayesian-based calibration method has the advantage of providing posterior distributions and thus giving a quantifiable estimate of the confidence in the prediction that can be used to adjust the control algorithm based on desired risk posture. Within the calibration routine, a Gaussian process model is first used as a surrogate for a simulated half-vehicle model which takes vehicle velocity and road surface roughness (GD) to output the axle acceleration. Then the calibration step takes in the observed axle acceleration and vehicle velocity and calibrates the Gaussian process model
Lewis, EdwinaParameshwaran, AdityaRedmond, LauraWang, Yue
Advances in computer aided engineering and numerical methods have made modeling and analyzing vehicle dynamics a key part of vehicle design. Over time, many tools have been developed to model different vehicle components and subsystems, enabling faster and more efficient simulations. Some of these tools use simplified mathematical models to achieve the desired performance. These models depend on model identification methods to determine the parameters and structure that best represent a system based on observed data. This work focuses on the development of a model identification for hydro bushings, a crucial component in nearly all ground vehicles. It introduces an innovative approach to identifying the dynamic properties of hydro bushings using the rapidly evolving physics-informed neural networks. The developed physics-informed network incorporates physical laws into its training process, allowing for an improved mapping of a hydro bushing’s excitation to its dynamic response. The
Koutsoupakis, JosefRibaric, AdrijanNolden, IngoKaryofyllas, GeorgeGiagopoulos, Dimitrios
Accurate mass estimation is essential for commercial heavy-duty vehicles (HDVs) because fluctuating payloads significantly impact energy consumption. Precise vehicle mass estimates enhance the accuracy of energy consumption models, leading to more effective energy management systems and performance optimization strategies. For example, improved energy estimates can lead to more optimized routing and refueling schedules, improving operational efficiency and reducing costs. For electric HDVs, accurate mass estimates are crucial for battery sizing, range prediction, and optimized charge scheduling. While direct mass measurements may be obtained through external weight-in-motion or specialized onboard weighing systems, this paper focuses on methods that use data from Controller Area Network systems for alternative real-time predictions. The challenge lies in identifying a method that performs well under the highly variable and often sparse data conditions typical of HDV driving datasets
Jayaprakash, BharatEagon, MatthewFakhimi, SetayeshKotz, AndrewNorthrop, William
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