Path-tracking control occupies a critical role within autonomous driving systems, directly reflecting vehicle motion and impacting both safety and user experience. However, the ever-changing vehicle states, road conditions, and delay characteristics of control systems present new challenges to the path tracking of autonomous vehicles, thereby limiting further enhancements in performance. This article introduces a path-tracking controller, time-varying gain-scheduled path-tracking controller with delay compensation (TGDC), which utilizes a linear parameter-varying system and optimal control theory to account for time-varying vehicle states, road conditions, and steering control system delays. Subsequently, a polytopic-based path-tracking model is applied to design the control law, reducing the computational complexity of TGDC. To evaluate the effectiveness and real-time capability of TGDC, it was tested under a series of complex conditions using a hardware-in-the-loop platform. The

Hu, XuePeng, Zhang, Yu, Hu, Yuxuan, Wang, Zhenfeng, Qin, Yechen

Enhancing Vehicle Safety: Investigating the Role of Active Anti-Roll Bars in Vehicle Dynamics

2024-36-0058

12/20/2024

A serious problem of public healthcare around the world is the number of road vehicle accidents, every year almost 1,3 million people die and approximately 20 to 50 million people suffer a non-fatal accident because of a road vehicle accident [1]. As a result of that, in 2021 the World Health Organization stated the “The Second Decade of Action for Road Safety”, which the goal is to prevent at least 50% of deaths and injuries due traffic by 2030. To achieve this goal, the automobile companies have invested in technology and products that can enhance vehicle safety. Despite exist some control systems able to reduce roll, and consequently the roll over, such as active suspension, semi-active suspension, and stability control systems, none of them have as main purpose reduce the number of rollovers. The following study aims to examine the effects of an active anti roll bar, to improve the vehicle dynamics during corners and reduce the risk of a rollover by reducing the roll of the sprung

Gomes, Pedro Carvalho, Teixeira, Evandro Leonardo Silva, Morais, Marcus Vinicius Girão, Fortaleza, Eugenio Liborio Feitora, Santos Gioria, Gustavo

Trajectory Planning and Tracking Control for Single Lane Changing with Different Driving Styles of Intelligent Vehicles Based on Seventh-Degree Polynomial

12-08-03-0028

12/14/2024

Single lane changing is one of the typical scenarios in vehicle driving. Planning an appropriate lane change trajectory is crucial in autonomous and semi-autonomous vehicle research. Existing polynomial trajectory planning mostly uses cubic or quintic polynomials, neglecting the lateral jerk constraints during lane changes. This study uses seventh-degree polynomials for lane change trajectory planning by considering the vehicle lateral jerk constraints. Simulation results show that the utilization of the seventh-degree method results in a 41% reduction in jerk compared to the fifth-degree polynomial. Furthermore, this study also proposes lane change trajectory schemes that can cater to different driving styles (e.g., safety, efficiency, comfort, and balanced performance). Depending on the driving style, the planned lane change trajectory ensures that the vehicle achieves optimal performance in one or more aspects during the lane change process. For example, with the trajectory that

Lai, Fei, Huang, Chaoqun

Active Hydro-Pneumatic Suspension Active Disturbance Rejection Sliding Mode Control for Improved Vehicle Stability

2024-28-0215

12/05/2024

Hydro-pneumatic suspension is widely used because of its desirable nonlinear stiffness and damping characteristics. However, the presence of parameter uncertainties and high nonlinearities in the system, lead to unsatisfactory control performance of the traditional controller in practical applications. In response to this challenge, this paper proposes a novel stability control method for active hydro-pneumatic suspension (AHPS). Firstly, a nonlinear mathematical model of the hydro-pneumatic suspension, considering the seal friction, is established based on the hydraulic principle and the knowledge of Fluid dynamics. On the basis of the established hydro-pneumatic suspension nonlinear model, a vehicle dynamics model is established. Secondly, an active disturbance rejection sliding mode controller (ADRSMC) is designed for the vertical, roll, and pitch motions of the sprung mass. The lumped disturbance caused by the model nonlinearities and uncertainties is estimated by the extended

Niu, Changsheng, Liu, Xiaoang, Jia, Xing, Gong, Bo, Xu, Bo

Integrated Control of Intelligent Vehicle Driving Stability Using Three-Dimensional Phase Space

10-09-01-0002

10/16/2024

To enhance vehicle dynamic stability during driving, we developed a three-dimensional phase space model that incorporates the sideslip angle of center of mass, yaw rate, and lateral load transfer rate. This model enabled real-time evaluation and active control of vehicle stability. First, longitudinal and lateral controllers were implemented to ensure precise vehicle trajectory. Second, a hierarchical control strategy was designed to actively manage the desired sideslip angle, yaw rate, and roll angle based on the vehicle’s destabilizing conditions, thereby maintaining the vehicle within a stable state space. We simulated and tested the stability analysis methods and integrated control strategies for both cars and trucks under DLC (double lane change) and CDC (circular driving condition) scenarios using joint simulations with CarSim/TruckSim and Simulink. The proposed integrated stability control strategy, which combined MPC-based trajectory tracking with direct yaw moment control and

Lai, Fei, Xiao, Hao, Huang, Chaoqun

Experimental Study on Quality Control and Variable Valve Timing Strategy of Hydrogen Engine for High Efficiency and Low Emission at Low Load

2024-01-5095

10/15/2024

In order to reduce the pumping loss of low loads and maximize the lean combustion advantage of hydrogen, the paper proposes a load control strategy based on hydrogen mass, called quality control, for improving thermal efficiency and emissions at low loads. The advantages of quality control and the effect of VVT on the combustion performance of hydrogen internal combustion engines under low loads were discussed. The results show that when the relative air–fuel ratio (λ) increases to more than 2.5, the NOx emissions are reduced to less than 3.5 g/kW · h at the brake mean effective pressure (BMEP) below 8 bar, especially when the BMEP is less than 5 bar, the NOx is within 0.2 g/kW · h. Compared to quantity control based on air mass, the quality control strategy based on hydrogen mass achieves over a 2.0% reduction in pumping loss at BMEP levels lower than 4.4 bar. Furthermore, it enhances thermal efficiency by up to 5% at low loads, while maintaining NOx emissions within 0.2 g/kW · h at

Li, Yong, Chen, Hong, Fu, Zhen, Du, Jiakun, Wu, Weilong

Integrated Motion Control Strategy Considering Parameter Robustness for Distributed Vehicle by Wire

10-08-04-0031

10/10/2024

To address the issues of functional conflicts in execution subsystems and the deterioration of control performance due to model parameter uncertainties in the motion control of distributed vehicle by wire, this article proposes an integrated control strategy considering parameter robustness. This strategy aims to compensate for model mismatch, resolve functional conflicts, and achieve motion coordination. Based on the over-actuation characteristics of distributed vehicle by wire, this article constructs the dynamic model and utilizes the tire cornering properties along with phase portraits to delineate the working regions of the execution subsystems. To deal with model parameter uncertainties and mismatch, tube-based model predictive control (tube-based MPC) is applied to the control strategy design, which compensates for model deviations through state feedback and constructs a robust positively invariant set (RPI) to constrain the system state. Correspondingly, the weights of control

Chen, Guoying, Bi, Chenxiao, Zhao, Xuanming, Yang, Liunan, Tang, Zhuo, Yu, Huili

Intelligent Vehicle Path Tracking and Stability Cooperative Control Strategy Based on Stable Domain

10-08-04-0025

08/14/2024

Vehicle path tracking and stability management are critical technologies for intelligent driving. However, their controls are mutually constrained. This article proposes a cooperative control strategy for intelligent vehicle path tracking and stability, based on the stable domain. First, using the vehicle’s two-degrees-of-freedom (DOF) model and the Dugoff tire model, a phase plane representation is constructed for the vehicle’s sideslip angle and sideslip angular velocity. An enhanced method utilizing five eigenvalues is employed to partition the vehicle stability domain. Second, by employing the divided vehicle stable domain, the design of a fuzzy controller utilizes the Takagi–Sugeno (TS) methodology to determine the weight matrix gain for path tracking and stability control. Subsequently, a fuzzy model predictive control (TS-MPC) cooperative control strategy is designed, which takes into account both the precision of path tracking and the stability of the vehicle. Finally, a

Jiang, Shuhuai, Wu, Guangqiang, Li, Yihang, Mao, Libo, Zhang, Dong

Analysis of road safety implementation strategies to support the easiest introduction of autonomous braking products for complex vehicle combinations

2024-36-0319

08/09/2024

In contrast to passenger cars, whose regulation allowed only a simple trailer combination, the autonomous technologies implementation of Electronic Stability Control (ESC) and Advanced Emergency Braking System (AEBS) for commercial vehicles demands more application and calibration efforts. At this case, the focus is on dynamic control of towing vehicles when applying the service brakes of trailer, in special when complex combination as bi-train and road-train, allowed in North and South America. However, the major risk is present occurrence when an ESC or AEBS equipped towing vehicles is connected to a double or triple trailer combination with a conventional braking system, it means: a system that is not equipped with Anti-lock Braking System (ABS). For instance, if during autonomous control, trailers wheels lock, a jackknifing phenomenon can easily occur. Therefore, in case longer and heavier vehicles (LHV) or megatrucks as called in Europe, the strategy for safety assistance systems

Guarenghi, Vinicius Mendes, Pizzi, Rafael Fortuna, Depetris, Alessandro, Pinto, Gustavo Laranjeira Nunes, Collobialli, Germano

Path-Tracking Control for Four-Wheel Steer/Drive Agricultural Special Electric Vehicles Considering Stability

2024-01-5051

04/25/2024

With the modernization of agriculture, the application of unmanned agricultural special vehicles is becoming increasingly widespread, which helps to improve agricultural production efficiency and reduce labor. Vehicle path-tracking control is an important link in achieving intelligent driving of vehicles. This paper designs a controller that combines path tracking with vehicle lateral stability for four-wheel steer/drive agricultural special electric vehicles. First, based on a simplified three-degrees-of-freedom vehicle dynamics model, a model predictive control (MPC) controller is used to calculate the front and rear axle angles. Then, according to the Ackermann steering principle, the four-wheel independent angles are calculated using the front and rear axle angles to achieve tracking of the target trajectory. For vehicle lateral stability, the sliding mode control (SMC) is used to calculate the required direct yaw moment control (DYC) of the vehicle, and wheel torque distribution

Huang, Bin, Yang, Nuorong, Ma, Liutao, Wei, Lexia

Vehicle Yaw Stability Model Predictive Control Strategy for Dynamic and Multi-Objective Requirements

2024-01-2324

04/09/2024

Vehicle yaw stability control (YSC) can actively adjust the working state of the chassis actuator to generate a certain additional yaw moment for the vehicle, which effectively helps the vehicle maintain good driving quality under strong transient conditions such as high-speed turning and continuous lane change. However, the traditional YSC pursues too much driving stability after activation, ignoring the difference of multi-objective requirements of yaw maneuverability, actuator energy consumption and other requirements in different vehicle stability states, resulting in the decline of vehicle driving quality. Therefore, a vehicle yaw stability model predictive control strategy for dynamic and multi-objective requirements is proposed in this paper. Firstly, the unstable characteristics of vehicle motion are analyzed, and the nonlinear two-degree-of-freedom vehicle dynamics models are established respectively. Secondly, the vehicle yaw stability control strategy is designed: The two

Wang, Hanlin, Wu, Jian, Chen, Zhicheng, He, Rui, Li, Haiqiao

A Novel Torque Distribution Approach of Four-Wheel Independent-Drive Electric Vehicles for Improving Handling and Energy Efficiency

2024-01-2315

04/09/2024

This paper presents a torque distribution strategy for four-wheel independent drive electric vehicles (4WIDEVs) to achieve both handling stability and energy efficiency. The strategy is based on the dynamic adjustment of two optimization objectives. Firstly, a 2DOF vehicle model is employed to define the stability control objective for Direct Yaw moment Control (DYC). The upper-layer controller, designed using Linear Quadratic Regulator (LQR), is responsible for tracking the target yaw rate and target sideslip angle. Secondly, the lower-layer torque distribution strategy is established by optimizing the tire load rate and motor energy consumption for dynamic adjustment. To regulate the weights of the optimization targets, stability and energy efficiency allocation coefficient is introduced. Simulation results of double lane change and split μ road conditions are used to demonstrate the effectiveness of the proposed DYC controller.

Dou, Jingyang, Chen, Zixuan, Zhang, Yunqing, Wu, Jinglai

Reference Velocity Estimation with Variable Gain Based on Powertrain Dynamics for Production Hybrid Electric Vehicle

2024-01-2147

04/09/2024

Reference velocity (i.e. the absolute velocity of vehicle center of gravity) is a key parameter for vehicle stability control functions as well as for the powertrain control functions of hybrid electric vehicle (HEV). Most reference velocity estimation methods employ the vehicle kinematic and tire dynamic equations to construct high order linear or nonlinear model with a set of parameters and sensor measurements. When using those models, delicate algorithm should be designed to prevent the estimates from deviating along with the increase of nonlinearity, modeling error and noise that introduced by high order, parameter approximation, and sensor measurements, respectively. Alternatively, to improve the function robustness and calibration convenience, a straightforward online estimation method is developed in the paper by using a second-order powertrain dynamic model that only need a small set of vehicle parameters and sensor values. First, the HEV powertrain dynamic model is established

Li, Huan, Liu, Xuewu, Wang, Jinhang, Chen, Lihua, Xu, Yin, Wu, Meng

Coordinated Control of Trajectory Tracking and Yaw Stability of a Hub-Motor-Driven Vehicle based on Four-Wheel-Steering

2024-01-2767

04/09/2024

In order to improve the trajectory tracking accuracy and yaw stability of vehicles under extreme conditions such as high speed and low adhesion, a coordinated control method of trajectory tracking and yaw stability is proposed based on four-wheel-independent-driving vehicles with four-wheel-steering. The hierarchical structure includes the trajectory tracking control layer, the lateral stability control decision layer, and the four-wheel angle and torque distribution layer. Firstly, the upper layer establishes a three-degree-of-freedom vehicle dynamics model as the controller prediction model, the front wheel steering controller is designed to realize the lateral path tracking based on adaptive model predictive control algorithm and the longitudinal speed controller is designed to realize the longitudinal speed tracking based on PID control algorithm. Then, the middle layer decides the rear wheel steering angle and the additional yaw moment to maintain the vehicle's yaw stability based

Fu, Yao, Xie, Renmin, Kaku, Chuyo, Zheng, Hongyu

Recursive Least Square Method with Multiple Forgot Factor for Mass Estimation of Heavy Commercial Vehicle

2024-01-2762

04/09/2024

Heavy commercial vehicles have large variations in load and high centroid positions, so it is particularly important to obtain timely and accurate load information during driving. If the load information can be accurately obtained and the braking force of each axle can be distributed on this basis, the braking performance and safety of the entire vehicle can be improved. Heavy commercial vehicle load information is different from passenger vehicles, so it is particularly important to study commercial vehicles engaged in freight and passenger transportation. Presently, numerous research endeavors focus on evaluating the quality of passenger vehicles. However, heavy commercial vehicles exhibit notable distinctions compared to their passenger counterparts. Due to substantial variations in vehicle mass pre and post-loading, coupled with notable suspension deformations, significant changes are observed. Hence, the task of estimating the mass of heavy commercial vehicles proves considerably

Zheng, Hongyu, Xin, Yafei, Yan, Yang

A Novel Method to Assess 4WS Vehicle Stability Based on Vehicle Sideslip Angle and Angular Velocity Phase Plane Method

2024-01-5004

01/18/2024

Vehicle dynamic control could improve vehicle performance. Vehicle stability is vital to the determination of vehicle dynamic control strategy. The phase plane method is one of the most common methods to judge vehicle stability. To determine the 4WS (four-wheel steering) vehicle stability status faster and more accurately, a novel method to assess the vehicle stability is based on the vehicle sideslip angle and angular velocity ( β-β˙) phase plane. At first, the 2 DOF (degree of freedom) model with a nonlinear tire model is established to acquire β-β˙ phase plane. Then the boundary of the stability region generated by the current method is compared. A crosspoint-ellipse method is provided based on the boundary comparison with the ideal boundary. The boundary function determined by the crosspoint-ellipse method is fitted based on vehicle dynamic theory and the boundary analysis with different steering angles, velocity, and road adhesion coefficient. At last, the transition area between

Peng, Dengzhi, Xia, Zuguo, Wang, Long, Liu, Qing

Prognosis of Engine Failure Based on Modelling by Using Live Parameter Data from Vehicle

2024-26-0266

01/16/2024

In the commercial vehicle business, vehicle availability is a pivotal factor for the profitability of the customer. Nonetheless, the intricate nature of the technologies embedded in modern day engines and exhaust after-treatment systems coupled with the variability of the duty cycles of end applications of the vehicles imposes added challenges on the vehicle's sustained performance and reliability. In this context, the ability to predict potential failures through tools like telematics and real-time data analytics presents a significant opportunity for original equipment manufacturers (OEMs) to deliver distinctive value to their customers. A modern-day commercial vehicle has a minimum of 5 micro controllers managing the performance and performing the on-board diagnostics of various sub-systems like engine, after treatment system, transmission, Cab and stability controls, the driver interface, and advisory systems etc., They operate independently and also sync with each other as master

K.S, Guru Prasanna, D.V, Ramkumar, S, Kannan, J, Narayana Reddy, K.R, Karthikeyan, D., Somsekar, M.D, Senthilkumar, N, Augustin Selvakumar, S.P, Suprabhan

Outrigger Design & Development for Vehicle Testing as per AIS 133

2024-26-0350

01/16/2024

Outrigger is mounted on the test vehicle during handling test maneuvers, such as double lane change, constant radius cornering, J-turn, etc. The aim of these outriggers is to protect the driver & vehicle from rollover during testing of vehicle electronic stability control systems under various dynamic maneuvers as per AIS 133. Outrigger design has to be achieved within a certain mass and roll moment of inertia as per AIS 133 guidelines. The paper discusses design which includes load path analysis, material comparison to maximize strength per unit weight, shape, dimensional finalization, etc. Torsion is generated when the skidpad comes in contact with the ground which we have tried to balance in the free body diagram (FBD) by changing the skidpad contact point for reducing the stress. Finite element analysis is done on the design developed after setting boundary conditions arrived from FBD. The developed design is then manufactured and successfully implemented in the testing of vehicles

Rathore, Gopal Singh, Chawla, Shubham

Estimation of Lateral Velocity and Cornering Stiffness in Vehicle Dynamics Based on Multi-Source Information Fusion

10-08-01-0003

01/04/2024

To address the challenge of directly measuring essential dynamic parameters of vehicles, this article introduces a multi-source information fusion estimation method. Using the intelligent front camera (IFC) sensor to analyze lane line polynomial information and a kinematic model, the vehicle’s lateral velocity and sideslip angle can be determined without extra sensor expenses. After evaluating the strengths and weaknesses of the two aforementioned lateral velocity estimation techniques, a fusion estimation approach for lateral velocity is proposed. This approach extracts the vehicle’s lateral dynamic characteristics to calculate the fusion allocation coefficient. Subsequently, the outcomes from the two lateral velocity estimation techniques are merged, ensuring rapid convergence under steady-state conditions and precise tracking in dynamic scenarios. In addition, we introduce a tire parameter online adaptive module (TPOAM) to continually update essential tire parameters such as

Chen, Guoying, Yao, Jun, Gao, Zhenhai, Gao, Zheng, Wang, Xinyu, Xu, Nan, Hua , Min

Attitude Stability Control and Visualization Simulation for Vertical Take-Off and Landing (VTOL) Fixed-Wing Aircraft

2023-01-7102

12/31/2023

Direct debugging of a vertical takeoff and landing (VTOL) fixed-wing aircraft’s control system can easily result in risk and personnel damage. It is effectively to employ simulation and numerical methods to validate control performance. In this paper, the attitude stabilization controller for VTOL fixed-wing aircraft is designed, and the controller performance is verified by MATLAB and visual simulation software, which significantly increases designed efficiency and safety of the controller. In detail, we first develop the VTOL fixed-wing aircraft’s six degrees of freedom kinematics and dynamics models using Simulink module, and the cascade PID control technique is applied to the VTOL aircraft’s attitude stabilization control. Then the visual simulation program records the flight data and displays the flight course and condition, which can validate the designed controller performance effectively. It can be concluded that the designed VTOL fixed-wing aircraft control visual simulation

Li, Wei, Shi, Jiekai, Wang, Fang, Bai, Jie

Fault Compensation Control for Regenerative Braking of Distributed Drive Electric Vehicle Based on Hierarchical Control

2023-01-7061

12/20/2023

For distributed drive electric vehicles (DDEV) equipped with an electronic hydraulic braking system (EHB) and four-wheel hub motors, when one or more hub motors have regenerative braking failure, because the braking torque of the four wheels is inconsistent, additional yaw moment will be formed on the vehicle, resulting in the loss of directional stability of the vehicle during braking. If it occurs at high speeds, it will further threaten driving safety. To solve the above problems, a new hierarchical control architecture is established in this paper. Firstly, taking DDEV as the research object, the vehicle dynamics model and EHB braking system model are built. Then, a state observer based on an adaptive Kalman filter is designed in the upper layer to estimate the vehicle’s sideslip angle and yaw rate in real time. In the judgment decision-making layer, the phase plane is used to divide the stability domain boundary of the vehicle, and the quasi-stability tolerance band judges the

Fang, Ting, Zhao, Linfeng, Hu, Jinfang, Mei, Zhen, Wang, Muyun, Sun, Bin

Real-Time Road Slope Estimation Based on GNSS/INS Fusion System Considering Slope Change

2023-01-7043

12/20/2023

For intelligent vehicles, a fast and accurate estimation of road slope is of great significance for many aspects, including the steering comfort, fuel economy, vehicle stability control, driving decision-making, etc. But the commonly used estimation methods nowadays usually demand additional sensors or complex dynamic models, causing increase in system complexity as well as decrease in accuracy. To solve these problems, this paper puts forward a real-time road slope estimation algorithm leveraging the relationship between pitch angle and road slope, which only requires low sensors cost and computational complexity. Firstly, a GNSS/INS fusion system is established to obtain the pitch angle with respect to the navigation frame, which couples the vehicle’s pitch angle in vehicle frame and road slope angle. Then, based on the different characteristics in frequency domain of the two components, frequency domain analysis is conducted and low-pass filter is used to separate out road slope

Chen, Mengyuan, Xiong, Lu, Gao, Letian

Automotive Stability Enhancement Systems

J2564_202312 (Current)

12/07/2023

The purpose of this SAE Information Report is to describe currently known automotive active stability enhancement systems, as well as identify common names which can be used to refer to the various systems and common features and functions of the various systems. The primary systems discussed are: a ABS - Antilock Brake Systems b TCS - Traction Control Systems c ESC - Electronic Stability Control The document is technical in nature and attempts to remain neutral regarding unique features that individual system or vehicle manufacturers may provide.

null, null

Contribution to the Objective Evaluation of Combined Longitudinal and Lateral Vehicle Dynamics in Nonlinear Driving Range

10-07-04-0034

10/19/2023

Since the complexity of modern vehicles is increasing continuously, car manufacturers are forced to improve the efficiency of their development process to remain profitable. A frequently mentioned measure is the consequent integration of virtual methods. In this regard, objective evaluation criteria are essential for the virtual design of driving dynamics. Therefore, this article aims to identify robust objective evaluation criteria for the nonlinear combined longitudinal and lateral dynamics of a vehicle. The article focuses on the acceleration in a turn maneuver since available objective criteria do not consider all relevant characteristics of vehicle dynamics. For the identification of the objective criteria, a generic method is developed and applied. First, an open-loop test procedure and a set of potential robust objective criteria are defined. Subsequently, suitable criteria are selected for different vehicle dynamics characteristics based on an investigation of Pearson

Raabe, Justus, Fontana, Fabian, Neubeck, Jens, Wagner, Andreas

Considerations for ISO 26262 ASIL Hazard Classification

J2980_202310 (Current)

10/02/2023

This SAE Recommended Practice presents a method and example results for determining the Automotive Safety Integrity Level (ASIL) for automotive motion control electrical and/or electronic (E/E) systems. The ASIL determination activity is required by ISO 26262-3, and it is intended that the process and results herein are consistent with ISO 26262. The technical focus of this document is on vehicle motion control systems. The scope of this SAE Recommended Practice is limited to collision-related hazards associated with motion control systems. This SAE Recommended Practice focuses on motion control systems since the hazards they can create generally have higher ASIL ratings, as compared to the hazards non-motion control systems can create. Because of this, the Functional Safety Committee decided to give motion control systems a higher priority and focus exclusively on them in this SAE Recommended Practice. ISO 26262 has a wider scope than SAE J2980, covering other functions and accidents

Functional Safety Committee

Recurrent Neural Network Model for On-Board Estimation of the Side-Slip Angle in a Four-Wheel Drive and Steering Vehicle

15-17-01-0003

09/23/2023

A valuable quantity for analyzing the lateral dynamics of road vehicles is the side-slip angle, that is, the angle between the vehicle’s longitudinal axis and its speed direction. A reliable real-time side-slip angle value enables several features, such as stability controls, identification of understeer and oversteer conditions, estimation of lateral forces during cornering, or tire grip and wear estimation. Since the direct measurement of this variable can only be done with complex and expensive devices, it is worth trying to estimate it through virtual sensors based on mathematical models. This article illustrates a methodology for real-time on-board estimation of the side-slip angle through a machine learning model (SSE—side-slip estimator). It exploits a recurrent neural network trained and tested via on-road experimental data acquisition. In particular, the machine learning model only uses input signals from a standard road car sensor configuration. The model adaptability to

Giuliacci, Tiziano Alberto, Ballesio, Stefano, Fainello, Marco, Mair, Ulrich, King, Julian

Robust Estimation of Vehicle Dynamic State Using a Novel Second-Order Fault-Tolerant Extended Kalman Filter

10-07-03-0019

05/25/2023

The vehicle dynamic state is essential for stability control and decision-making of intelligent vehicles. However, these states cannot usually be measured directly and need to be obtained indirectly using additional estimation algorithms. Unfortunately, most of the existing estimation methods ignore the effect of data loss on estimation accuracy. Furthermore, high-order filters have been proven that can significantly improve estimation performance. Therefore, a second-order fault-tolerant extended Kalman filter (SOFTEKF) is designed to predict the vehicle state in the case of data loss. The loss of sensor data is described by a random discrete distribution. Then, an estimator of minimum estimation error covariance is derived based on the extended Kalman filter (EKF) framework. Finally, experimental tests demonstrate that the SOFTEKF can reduce the effect of data loss and improve estimation accuracy by at least 10.6% compared to the traditional EKF and fault-tolerant EKF.

Wang, Yan, Wei, Henglai, Hu, Binbin, Lv, Chen

Development of an Electronic Stability Control Algorithm for All-Terrain Vehicles

2023-01-0661

04/11/2023

An Electronic Stability Control algorithm has been developed for All-Terrain Vehicles. The algorithm is implemented on SEA’s Robotic Test Driver which has been customized to drive ATVs unmanned. The ESC algorithm is incorporated in the real-time controller. When activated, ESC monitors vehicle states and when they exceed pre-determined thresholds, ESC intervenes by dropping throttle and applying the vehicle’s brakes. The intention of this algorithm is to prevent yaw instability and ultimately limit the vehicle’s roll angle. ESC is implemented on two vehicles, which exhibit varying degrees of understeer. Test data is provided to illustrate the determination in setting threshold limits. The efficacy of the ESC is demonstrated by showing the system being enabled and disabled.

Zagorski, Scott, Heydinger, Gary

The Integrated Trajectory Tracking, Yaw Stability and Roll Stability Model Predictive Control for Autonomous Vehicle in Limited Handling Condition

2023-01-0667

04/11/2023

In the current literature, the research studies on the trajectory tracking control and stability control strategy for autonomous vehicles in limited condition mostly focus on the yaw plane control, but few of the studies have considered the combined control performance of trajectory tracking, yaw and roll stability, and the roll stability is critical under the extreme cornering condition for autonomous vehicles. Aiming at the above shortages, this study designs the model predictive control (MPC) strategy for the autonomous vehicles under the limited handling condition, which integrates the front and rear wheel active steering control, four-wheel independent drive and braking control and active suspension control to comprehensively improve the trajectory tracking accuracy, yaw plane stability and roll plane stability of the vehicle under the extreme condition. In the internal prediction model of the MPC, the yaw plane dynamics, roll plane dynamics and suspension system models are

Li, Boyuan, Li, Wenfei, Hua, Wei, Velenis, Efstathios

Electronically Controlled Brake System with Two-Channel Pressure Control for Electric Vehicles

2023-01-0663

04/11/2023

In this study, we introduce an electronically controlled brake system (ECB) that can be applied to electric vehicles (EVs) and internal combustion engine vehicles (ICEVs). The main features of the ECB include maximizing the regenerative energy while maintaining vehicle stability and ensuring redundancy in automatic braking. The brake system consists of upper and lower units. The newly developed upper unit has a brake-by-wire configuration and can control the front and rear wheel pressures separately. Hereinafter, controlling the front and rear wheel pressures separately is referred to as two-channel pressure control. The regenerated energy can be maximized while appropriately maintaining the distribution of the front and rear braking forces based on the two-channel pressure control during regenerative cooperation. The lower unit is a conventional hydraulic unit for executing anti-lock brake control, electronic stability control and so on. Each of the upper and lower units has a

Watanabe, Shunya, Yamamoto, Takayuki, Masuda, Yoshio, Yamakita, Hiroki

Sensorless Control of a Brushless Motor for the ESC Unit

2023-01-0452

04/11/2023

In general, automatic braking uses an electric stability control (ESC) hydraulic unit that can automatically increase the hydraulic pressure in the wheel cylinder (hereinafter called wheel pressure), independent of the driver’s braking operation. The hydraulic unit should have sufficient pressure response to apply autonomous emergency braking (AEB). It was necessary for the hydraulic unit to have a high flow rate for the pressure response. To satisfy the performance requirements of the AEB, a brushless motor, which has a high maximum rotational speed and good response, is adopted for the hydraulic unit. Furthermore, sensorless control, which does not require a rotation angle sensor, has been developed so that the motor size can be small and common to conventional units. The developed sensorless control can switch the driving methods in three states: pre-rotation, low speed, and high speed. In the pre-rotational state, the magnetic poles are judged to quickly determine the initial

Kawamura, Hikaru, Kokubo, Koichi, Naito, Masayuki, Iida, Takanori, Takahashi, Atsushi, Takahashi, Tomoya

Combined Path Following and Vehicle Stability Control using Model Predictive Control

2023-01-0645

04/11/2023

This paper presents an innovative combined control using Model Predictive Control (MPC) to enhance the stability of automated vehicles. It integrates path tracking and vehicle stability control into a single controller to satisfy both objectives. The stability enhancement is achieved by computing two expected yaw rates based on the steering wheel angle and on lateral acceleration into the MPC model. The vehicle's stability is determined by comparing the two reference yaw rates to the actual one. Thus, the MPC controller prioritises path tracking or vehicle stability by actively varying the cost function weights depending on the vehicle states. Using two industrial standard manoeuvres, i.e. moose test and double lane change, we demonstrate a significant improvement in path tracking and vehicle stability of the proposed MPC over eight benchmark controllers in the high-fidelity simulation environment. The numerous benchmark controllers use different path tracking and stability control

Lenssen, Daan, Bertipaglia, Alberto, Santafe, Felipe, Shyrokau, Barys

Interconnected Roll Stability Control System for Semitrucks with Double Trailers

2023-01-0906

04/11/2023

This paper provides a simulation analysis of a novel interconnected roll stability control (RSC) system for improving the roll stability of semitrucks with double trailers. Different from conventional RSC systems where each trailer’s RSC module operates independently, the studied interconnected RSC system allows the two trailers’ RSC systems to communicate with each other. As such, if one trailer’s RSC activates, the other one is also activated to assist in further scrubbing speed or intervening sooner. Simulations are performed using a multi-body vehicle dynamics model that is developed in TruckSim® and coupled with the RSC model established in Simulink®. The dynamic model is validated using track test data. The simulation results for a ramp steer maneuver (RSM) and sine-with-dwell (SWD) maneuver indicate that the proposed RSC system reduces lateral acceleration and rollover index for both trailers, decreasing the likelihood of wheel tip-up and vehicle rollover. Specifically, the

Zheng, Xiaohan, Chen, Yang, Ahmadian, Mehdi

Modeling and Verification of Tire Nonlinearity Effect on Accuracy of Vehicle Yaw Rate Calculation

2023-01-0753

04/11/2023

The desired yaw rate is a vital target parameter for vehicle stability control, which is currently determined as a steady-state yaw rate by the linear single-track vehicle model. Tire nonlinearity deteriorates the effect of vehicle stability control at larger lateral acceleration. This paper proposes a new calculation method of the steady-state yaw rate considering the tire nonlinearity based on the brush tire model. To validate and verify the proposed method, step steering tests of the target vehicle under different lateral accelerations are carried out on a real proving ground. The results show that when the lateral acceleration is relatively small, the difference between the calculation results of the proposed method and the traditional one is not apparent, and both methods can provide a good estimation for the steady-state yaw rate; however, when the lateral acceleration is relatively large, the difference becomes apparent. It can be shown that the linear tire model cannot be able

Min, Delei, Wei, Yintao

Pre-emptive Braking Control for Stability Improvement of Autonomous Vehicles on a Curved Road Based on Vehicle-to-Everything Technology

02-16-03-0018

03/15/2023

Vehicle-to-everything (V2X) technology has played an important role in improving the active safety of autonomous vehicles. In order to improve the stability of the autonomous vehicle on the curved road, this article presents a pre-emptive braking control method based on V2X technology. Instead of using the active safety system to try to stabilize the vehicle in case of danger, the pre-emptive braking action is proposed to reduce the vehicle speed in advance to a level that allows safe navigation of the turn to avoid danger. It is assumed that the friction and curvature of the curved road ahead can be obtained through V2X technology. Combined with a linear two degrees of freedom (2-DOF) bicycle model, an optimal control method is adopted to calculate the front and rear wheel steering angles to track the centerline of the curve lane. A more complex vehicle dynamics model established earlier is selected for simulation analysis to verify the proposed control method. The results show that

Huang, Chaoqun, Lai, Fei

Forward Collision Warning and Automatic Emergency Braking Test Procedure and Minimum Performance Requirements - Truck and Bus

J3029_202301 (Current)

01/17/2023

This SAE Recommended Practice (RP) establishes uniform powered vehicle-level test procedure for forward collision warning (FCW) and automatic emergency braking (AEB) used in trucks and buses greater than 10000 pounds (4535 kg) GVWR equipped with pneumatic brake systems for detecting, warning, and avoiding potential collisions. This RP does not apply to electric powered vehicles, trailers, dollies, etc., and does not intend to exclude any particular system or sensor technology. These FCW/AEB systems utilize various methodologies to identify, track, and communicate data/information to the operator and vehicle systems to warn, intervene, and/or mitigate in the momentary longitudinal control of the vehicle. This specification will test the functionality of the FCW/AEB (e.g., ability to detect objects in front of the vehicle), its ability to indicate FCW/AEB engagement and disengagement, the ability of the FCW/AEB to notify the human machine interface (HMI) or vehicle control system that an

null, null

Chassis Dynamometer Simulation of Road Load Using Coastdown Techniques

J2264_202301 (Current)

01/13/2023

This procedure covers vehicle operation and electric dynamometer (dyno) load coefficient adjustment to simulate track road load within dynamometer inertia and road load simulation capabilities.

Light Duty Vehicle Performance and Economy Measure Committee

Event Data Recorder - Output Data Definition

J1698/1_202301 (Current)01/13/2023

Event Data Recorder Committee

LSTM-Based Trajectory Tracking Control for Autonomous Vehicles

2022-01-7079

12/22/2022

With the improvement of sensor accuracy, sensor data plays an increasingly important role in intelligent vehicle motion control. Good use of sensor data can improve the control of vehicles. However, data-based end-to-end control has the disadvantages of poorly interpreted control models and high time costs; model-based control methods often have difficulties designing high-fidelity vehicle controllers because of model errors and uncertainties in building vehicle dynamics models. In the face of high-speed steering conditions, vehicle control is difficult to ensure stability and safety. Therefore, this paper proposes a hybrid model and data-driven control method. Based on the vehicle state data and road information data provided by vehicle sensors, the method constructs a deep neural network based on LSTM and Attention, which is used as a compensator to solve the performance degradation of the LQR controller due to modeling errors. The compensator takes a multidimensional sequence of

Chen, ShiChang, Yin, Zhishuai, Yu, Jia, Zhang, Ming

Research on Collision Avoidance and Vehicle Stability Control of Intelligent Driving Vehicles in Harsh Environments

2022-01-7128

12/16/2022

Aiming at the problems of ineffective collision avoidance and vehicle instability in the process of vehicle emergency braking in road conditions with low adhesion and sudden change in adhesion coefficient, a stability-coordinated emergency braking and collision avoidance control system SEBCACS) is proposed. First, according to the motion of the ego vehicle and the target vehicle as well as the road adhesion conditions, a collision time model is proposed for evaluating the vehicle collision risk, and the expected deceleration required to avoid the collision is calculated. Then, the MPC method is used to calculate the yaw moment generated by the four-wheel braking force required to maintain vehicle stability according to the actual and reference yaw rate and side slip angle deviation. Then it is decided whether to implement additional yaw moment control according to the body stability evaluation results. Finally, the required four-wheel braking force is calculated according to the

Liu, Zhaoyong, Tan, Xiaoqiang, Long, Yiming, Li, Yihang, Shao, Weishu, Wen, Gaobo, Wu, Guangqiang

Research on Hierarchical Stability Control Strategy Based on Model Predictive Control for Multi-axis H-Type Distributed Drive Electric Vehicles

14-12-01-0007

10/18/2022

As a special distributed drive configuration, H-type distributed drive electric vehicle (H-DDEV) has better off-road ability and trafficability than traditional distributed drive electric vehicle, which attracts the interest of researchers deeply. However, due to its unique structure, how to ensure the stability of H-DDEV is still a key control problem. In this article, a hierarchical stability control algorithm based on model predictive control (HC-MPC) is proposed for H-DDEV. First, the vehicle dynamics model is established, which can reflect the dynamic characteristics of H-DDEV. Then, the HC-MPC is designed. In the upper layer, the nonlinear two-degrees-of freedom (2-DOF) model is applied in MPC, which can improve the control accuracy without increasing complexity through local linearization. In the lower layer, the optimal distribution equation is constructed to coordinate the torque distribution, which can make full use of the motor drive/braking characteristics and protecting

Zeng, Xiaohua, Gao, Haoming, Song, Dafeng, Wu, Ziqiao

Articulated Vehicle Stability Control Using Brake-Based Torque Vectoring on Trailer Using Nonlinear Model Predictive Control

02-16-01-0007

10/17/2022

Unstable articulated vehicles pose a serious threat to the occupants driving them as well as the occupants of the vehicles around them. Articulated vehicles typically experience three types of instability: snaking, jack-knifing, and rollover. An articulated vehicle subjected to any of these instabilities can result in major accidents. In this study a Nonlinear Model Predictive Control (NMPC) that applies brake-based torque vectoring on the trailer is developed to improve the articulated vehicle stability. The NMPC formulation includes tire saturation and applies constraints to prevent rollover. The controller output is a left and right brake force allowing the longitudinal velocity change to be incorporated into the model. Simulations were conducted to instigate snaking and jack-knifing and show the NMPC controller result compared to a simple proportional controller. The NMPC controller can prevent these instabilities and improves the overall handling and safety of the articulated

Catterick, Jamie, Botha, Theunis, Els, Schalk

An Automated Procedure for Implementing Steer Input during Ditch Rollover CAE Simulation

2022-28-036510/05/2022

Vehicle manufacturers conduct tests to develop crash sensing system calibrations. Ditch fall-over is one of a suite of laboratory tests used to develop rollover sensing calibrations that can trigger deployment of safety devices like roof rail airbags and seat belt pretensioners. The ditch fall-over test simulates a flat road followed by a ditch on one side of the road. The vehicle heads into the ditch and the driver applies swift steer input once the ditch slope is sensed. Typically, the steer input is applied when the two down-slope wheels on the ditch side enter the ditch. Multi-Body Dynamics (MBD) software can be used for virtual simulation of these test events. Conventionally in simulations, the vehicle-model is run without steer input and the marking line crossing time is observed/manually recorded from observation of simulation video. This recorded time is used to apply the steer input and the full event is then re-simulated. This latched time varies with respect to vehicle speed

Gawade, Tushar Rajaram, Wong, Jason

Investigation of Vehicle Stability by Integration of Active Suspension, Torque Vectoring, and Direct Yaw Control

10-06-04-0029

10/05/2022

In this article, the integrated vehicle stability control strategy by a combination of active suspension (AS), torque vectoring control (TVC), and direct yaw control (DYC) is proposed to investigate the improvement of vehicle stability. By considering the differences of control targets for variable vehicle subsystems, the proposed strategy includes the three levels of hierarchical structure to coordinate these vehicle subsystems for optimal functions in relation to the vehicle subsystems. At the upper level, the vehicle estimates the posture and dynamic state. At the middle level of the structure, the method of coordination is introduced. Furthermore, the designed AS is based on H∞ logic theory. The TVC design is based on the principle of indirect yaw moment theory, and the DYC design is based on linear quadratic regulator (LQR) control algorithm are demonstrated at the lower level. In order to verify the control effect, the MATLAB/Simulink platform is used for the establishment of the

Hu, Zhiming, Liao, Yinsheng, Liu, Jianjian, Xu, Haolun

Compensatory Camber Angle Goniometry for Defying Effect of Overturning Moment Generation on Each Tire’s Contact Patch Area

SAE-PP-0030109/24/2022

Idea-based control procedures are to assist drivers in handling/stabilizing or alarming problematic lane-departures, for instance, Electronic Stability Programs, Lane-departure Warning Systems, Anti-lock Braking System, etc. While a revolving, momentary Center of Pressure on the chassis, is pointed unevenly to the C.G in a 2D cartesian coordinates with two axes of overturning and departure. How to quantitate bodyweight forces on wheels, is discussed based on height differences of each wheel’s spring related to the others. Road departures are fractionated by oversteering and understeering concepts as driving in a devious path. Because of Overturing Moments generation due to the tires’ lateral forces existence, some inequivalent carcass camber angles are modeled which enter into the wheels’ tire contact patches laterally . A TOM control method is described to compensate the effect of each generating carcass camber angle on decrease of the tire’s contact patch width. This work through the

Maleki, Mahdi, Ghonjizadeh Samani, Ali, qazanfari nezhad, asal

Items per page:

1 – 50 of 454