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Engineering 2024年第2期33卷 108-120页

作者： Kang Yuan yanjun huang Shuo Yang Zewei Zhou Yulei Wang Dongpu Cao Hong Chen College of Electronic and Information Engineering Tongji UniversityShanghai 201804China Shanghai Institute of Intelligent Science and Technology Tongji UniversityShanghai 201210China School of Automotive Studies Tongji UniversityShanghai 201804China School of Vehicle and Mobility Tsinghua UniversityBeijing 100084China

Decision-making and motion planning are extremely important in autonomous driving to ensure safe driving in a real-world *** study proposes an online evolutionary decision-making and motion planning framework for autonomous driving based on a hybrid data-and model-driven ***,a data-driven decision-making module based on deep reinforcement learning(DRL)is developed to pursue a rational driving performance as much as ***,model predictive control(MPC)is employed to execute both longitudinal and lateral motion planning *** constraints are defined according to the vehicle’s physical limit to meet the driving task ***,two principles of safety and rationality for the self-evolution of autonomous driving are proposed.A motion envelope is established and embedded into a rational exploration and exploitation scheme,which filters out unreasonable experiences by masking unsafe actions so as to collect high-quality training data for the DRL *** with a high-fidelity vehicle model and MATLAB/Simulink co-simulation environment are conducted,and the results show that the proposed online-evolution framework is able to generate safer,more rational,and more efficient driving action in a real-world environment.

关键词： Autonomous driving Decision-making Motion planning Deep reinforcement learning Model predictive control

基于时序差分学习模型预测控制的一体化自动驾驶换道策略

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机械工程学报 2024年第10期60卷 329-338页

作者：杨硕李时珍赵中原黄小鹏黄岩军同济大学汽车学院上海201804 南京信息工程大学自动化学院南京210044 中电科东方通信集团有限公司广东519060

具有自进化能力的自动驾驶换道策略有望在复杂开放的交通环境中提升性能,以应对更多的未知场景。时序差分学习模型预测控制(Temporal difference learning for model predictive control,TD-MPC)结合有模型和无模型强化学习方法的优势,... 详细信息

具有自进化能力的自动驾驶换道策略有望在复杂开放的交通环境中提升性能,以应对更多的未知场景。时序差分学习模型预测控制(Temporal difference learning for model predictive control,TD-MPC)结合有模型和无模型强化学习方法的优势,具有学习效率高、性能优异的特点。基于此,为了提高自动驾驶换道策略的整体性能,提出基于TD-MPC的自动驾驶一体化换道策略。具体来说,针对自动换道问题,提出基于驾驶倾向网络的一体化自动驾驶换道策略架构,构建强化学习问题并设计完备的奖励函数,对决策规划优化问题进行统一求解。应用TD-MPC算法设计内部模型来预测未来状态和奖励,实现短时域内的局部轨迹优化,同时使用时序差分学习实现对长期汇报的估计,以得到驾驶倾向网络参数。所提出方法在高保真仿真环境中被验证,结果表明,所提出方法相比规则方案保证行驶效率,并且提高安全性和舒适性。同时与软演员-评论家算法(Soft actor critic,SAC)相比,实现了7~9倍的学习效率提升。

关键词：自动驾驶强化学习一体化决策规划

Effects of fastigial nucleus electrical stimulation on lateral ventricle nestin expression after focal cerebral ischemia/reperfusion in adult rats

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Neural Regeneration Research 2008年第4期3卷 410-414页

作者： yanjun huang Yong Luo Department of Neurology First Affiliated Hospital of Chongqing Medical University Chongqing 400016 China Chongqing Key Laboratory of Neurology Chongqing 400016 China Department of Neurology Third People＇s Hospital of Mianyang City Mianyang 621000 Sichuan Province China

BACKGROUND： Previous studies have confirmed that fastigial nucleus electrical stimulation can induce endogenous neuroprotective mechanisms and produce wide and long-lasting neuroprotective effects. Nevertheless, the precise mechanisms remain poorly understood. OBJECTIVE： This study was designed to observe the effects of fastigial nucleus electrical stimulation on nestin-positive cell expression in adult rat lateral ventricle after focal cerebral ischemia/reperfusion, as well as neurological functional changes as a function of time. DESIGN： A randomized controlled animal experiment. SETTING： Department of Neurology, First Affiliated Hospital of Chongqing Medical University; Chongqing Key Laboratory of Neurology. MATERIALS： This study was performed in the Department of Neurology, First Affiliated Hospital of Chongqing Medical University and Chongqing Key Laboratory of Neurology from September 2004 to February 2006. A total of 180 healthy, adult, male Wistar rats, aged 8 weeks old, were provided by the Laboratory Animal Center of Chongqing Medical University. The main reagents and equipments were as follows： rabbit anti-rat nestin monoclonal antibody （Wuhan Boster Company, China）. METHODS： The included male Wistar rats were randomly divided into 5 groups： normal control, sham-operated, model, fastigial nucleus sham-stimulation （sham-stimulation for short）, and fastigial nucleus electrical stimulation （stimulation for short） groups. Six time points （1 hour of ischemia and 1, 3, 7, 14, 21, and 28 days of reperfusion, 6 rats per time point） were allotted to each group. Cerebral ischemia/reperfusion was performed by occlusion to the right middle cerebral artery with suture, followed by suture removal. In the stimulation group, subsequent to reperfusion, the rat left cerebellar fastigial nucleus was immediately subjected to 1 hour of stimulation. After anesthesia, the rat left cerebellar fastigial nucleus was stimulated for 1 hour using a square-wave electronic stimulator w

关键词： fastigial nucleus electrical stimulation focal cerebral ischemia/reperfusion nestin lateralventricle rats

Study on Rollover Index and Stability for a Triaxle Bus

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Chinese Journal of Mechanical Engineering 2019年第4期32卷 153-167页

作者： Zhilin Jin Jingxuan Li yanjun huang Amir Khajepour Department of Vehicle Engineering Nanjing University of Aeronautics & Astronautics Nanjing Jiangsu Province 210016 China Department of Mechanical & Mechatronics Engineering University of Waterloo Waterloo ON N 2L3G 1 Canada

Vehicle rollover, and its resulting fatalities, is an actively researched topic especially for multi-axle vehicles in the field of vehicle dynamics and control. This paper first presents a new rollover index for a triaxle bus to accurately evaluate its rollover possibility and then discusses the influence laws of the vehicle rollover dynamics to explore the mechanism of its stability. First, a six degree of freedom rollover model of the triaxle bus is developed, including lateral, yaw, roll motion of the sprung mass of the front/rear axle, and roll motion of the unsprung mass of the front/rear axle. Next, some key parameters of the vehicle rollover model are identified. A new rollover index is deduced according to the basics of vehicle dynamics, to predict vehicle rollover risk for the triaxle bus, which is verified by TruckSim. Furthermore, the influence laws of vehicle rollover dynamics by vehicle parameters and road parameters are discussed based on the simulation results. More importantly, the results show that the new method of modeling can precisely describe the rollover dynamics of the studied bus, and the proposed new index can e ectively evaluate the rollover possibility. Therefore, this study provides a theoretical basis to improve anti-rollover ability for triaxle buses.

关键词： Rollover stability Dynamic model Triaxle bus Rollover index Vehicle active safety

Fuzzy Consistent Relation and Decision Making

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Journal of Systems Engineering and Electronics 1998年第2期9卷 14-18页

作者： Yao, Min huang, yanjun Dept. of Computer Science Hangzhou University 310028 P. R. China Dept. of Finance Hangzhou University 310028 P. R. China

This paper presents a kind of fuzzy consistent relation, discusses its main properties - center-division transitivity, describes its combined operation. At the same time, introduce the applications of fuzzy consisten... 详细信息

关键词： Fuzzy consistent relation Center-division transitivity Decision making

Vertical Tire Forces Estimation of Multi-Axle Trucks Based on an Adaptive Treble Extend Kalman Filter

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Chinese Journal of Mechanical Engineering 2021年第3期34卷 317-335页

作者： Buyang Zhang Ting Xu Hong Wang yanjun huang Guoying Chen Jihua Laboratory Foshan 528200GuangdongChina State Key Laboratory of Automotive Simulation and Control Jilin UniversityChangchun 130022China Tsinghua Intelligent Vehicle Design and Safety Research Institute Tsinghua UniversityBeijing 100084China Department of Mechanical and Mechatronics Engineering University of WaterlooWaterlooCanada.

Vertical tire forces are essential for vehicle modelling and dynamic ***,an evaluation of the vertical tire forces on a multi-axle truck is difficult to *** current methods require a large amount of experimental data and many sensors owing to the wide variation of the parameters and the *** simplify the design process and reduce the demand of the sensors,this paper presents a practical approach to estimating the vertical tire forces of a multi-axle truck for dynamic *** estimation system is based on a novel vertical force model and a proposed adaptive treble extend Kalman filter(ATEKF).To adapt to the widely varying parameters,a sliding mode update is designed to make the ATEKF adaptive,and together with the use of an initial setting update and a vertical tire force adjustment,the overall system becomes more *** particular,the model aims to eliminate the effects of the over-constraint and the uneven weight *** results show that the ATEKF method achieves an excellent performance in a vertical force evaluation,and its performance is better than that of the treble extend Kalman filter.

关键词： Estimation theory Adaptive treble extend Kalman filter Vehicle dynamics Multi-axle truck Vertical tire force estimation

A Combined Reinforcement Learning and Model Predictive Control for Car-Following Maneuver of Autonomous Vehicles

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Chinese Journal of Mechanical Engineering 2023年第3期36卷 315-325页

作者： Liwen Wang Shuo Yang Kang Yuan yanjun huang Hong Chen School of Automotive Studies Tongji UniversityShanghai 201804China Shanghai Institute of Intelligent Science and Technology Tongji UniversityShanghai 201804China College of Electronic and Information Engineering Tongji UniversityShanghai 201804China

Model predictive control is widely used in the design of autonomous driving ***,its parameters are sensitive to dynamically varying driving conditions,making it difficult to be implemented into *** a result,this study presents a self-learning algorithm based on reinforcement learning to tune a model predictive ***,the proposed algorithm is used to extract features of dynamic traffic scenes and adjust the weight coefficients of the model predictive *** this method,a risk threshold model is proposed to classify the risk level of the scenes based on the scene features,and aid in the design of the reinforcement learning reward function and ultimately improve the adaptability of the model predictive controller to real-world *** proposed algorithm is compared to a pure model predictive controller in car-following *** to the results,the proposed method enables autonomous vehicles to adjust the priority of performance indices reasonably in different scenarios according to risk variations,showing a good scenario adaptability with safety guaranteed.

关键词： Model predictive control Reinforcement learning Autonomous vehicles

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多智能网联汽车轨迹规划:现状与展望

机械工程学报 2024年第10期60卷 129-146页

作者：戢杨杰张馨雨杨紫茹周上航黄岩军曹建永熊璐余卓平同济大学汽车学院上海201804 上海机动车检测认证技术研究中心有限公司上海201800

轨迹规划是自动驾驶汽车的基本功能。随着车用无线通信技术(Vehicle to everything,V2X)技术的发展,自动驾驶汽车具备智能网联功能,这些汽车被称为智能网联汽车。智能网联技术可以为自动驾驶汽车带来大量信息,增强不同自动驾驶汽车之间... 详细信息

轨迹规划是自动驾驶汽车的基本功能。随着车用无线通信技术(Vehicle to everything,V2X)技术的发展,自动驾驶汽车具备智能网联功能,这些汽车被称为智能网联汽车。智能网联技术可以为自动驾驶汽车带来大量信息,增强不同自动驾驶汽车之间的合作,并为轨迹规划提供额外的优化空间,以减少驾驶时间,提高驾驶舒适性和安全性。与传统的单车轨迹规划相比,多车轨迹规划可以充分利用智能网联汽车的技术优势,为多个自动驾驶汽车规划合适的轨迹。以结构化场景和非结构化场景的分类综述典型的多车轨迹规划应用场景,总结不同的多车轨迹规划合作规划策略和特点。总结用于多车轨迹规划的各种方法,包括传统的流水线规划方法和端到端方法,并对多车轨迹规划的试验进行归纳。基于当前研究现状,提出多车轨迹规划面临的挑战和未来的研究方向,为智能交通系统领域的研究人员提供启发和参考。

关键词：自动驾驶汽车轨迹规划智能网联汽车

Comparative Study of Trajectory Tracking Control for Automated Vehicles via Model Predictive Control and Robust H-infinity State Feedback Control

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Chinese Journal of Mechanical Engineering 2021年第4期34卷 168-181页

作者： Kai Yang Xiaolin Tang Yechen Qin yanjun huang Hong Wang Huayan Pu College of Mechanical and Vehicle Engineering Chongqing UniversityChongqing 400000China School of Mechanical Engineering Beijing Institute of TechnologyBeijing 100080China School of Automotive Studies Tongji UniversityShanghai 201804China School of Vehicle and Mobility Tsinghua UniversityBeijing 100080China

A comparative study of model predictive control(MPC)schemes and robust Hstate feedback control(RSC)method for trajectory tracking is proposed in this *** main objective of this paper is to compare MPC and RSC controllers’performance in tracking predefined trajectory under different *** controller is designed based on the simple longitudinal-yaw-lateral motions of a single-track vehicle with a linear tire,which is an approximation of the more realistic model of a vehicle with double-track motion with a non-linear tire *** is designed on the basis of the same method as adopted for the MPC controller to achieve a fair ***,three test cases are built in CarSim-Simulink joint ***,the verification test is used to test the tracking accuracy of MPC and RSC controller under well road ***,the double lane change test with low road adhesion is designed to find the maximum velocity that both controllers can carry out while guaranteeing ***,an extreme curve test is built where the road adhesion changes suddenly,in order to test the performance of both controllers under extreme ***,the advantages and disadvantages of MPC and RSC under different scenarios are also discussed.

关键词： Trajectory tracking Automated vehicles Model predictive control Robust H∞state feedback control

Kalman Filter-Based Fusion Estimation Method of Steering Feedback Torque for Steer-by-Wire Systems

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Automotive Innovation 2021年第4期4卷 430-439页

作者： Lin Zhang Qiang Meng Hong Chen yanjun huang Yang Liu Konghui Guo School of Automotive Studies Tongji UniversityShanghaiChina Clean Energy Automotive Engineering Center Tongji UniversityShanghaiChina KH Automotive Technologies Co LtdChangchunChina

Universal challenge lies in torque feedback accuracy for steer-by-wire systems,especially on uneven and low-friction ***,this paper proposes a fusion method based on Kalman filter that combines a dynamics-reconstruction method and disturbance observer-based *** dynamics-reconstruction method is designed according to the vehicle dynamics and used as the prediction model of the Kalman *** the disturbance observer-based method is performed as an observer model of the Kalman *** performance of all three methods is comprehensively evaluated in a hardware-in-the-loop *** results show that the proposed fusion method outperforms dynamics reconstruction method and disturbance observer-based ***,compared with the dynamics-reconstruction method,the root mean square error is reduced by 36.58%at the maximum on the flat *** with the disturbance observer-based method,the root mean square error is reduced by 39.11%at the maximum on different-friction and uneven road.

关键词： Kalman filter Steering feedback torque estimation Steer-by-wire system