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Perception Enhanced Deep Deterministic Policy Gradient for Autonomous Driving in Complex Scenarios
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作者 Lyuchao Liao Hankun Xiao +3 位作者 Pengqi Xing Zhenhua Gan Youpeng He Jiajun Wang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第7期557-576,共20页
Autonomous driving has witnessed rapid advancement;however,ensuring safe and efficient driving in intricate scenarios remains a critical challenge.In particular,traffic roundabouts bring a set of challenges to autonom... Autonomous driving has witnessed rapid advancement;however,ensuring safe and efficient driving in intricate scenarios remains a critical challenge.In particular,traffic roundabouts bring a set of challenges to autonomous driving due to the unpredictable entry and exit of vehicles,susceptibility to traffic flow bottlenecks,and imperfect data in perceiving environmental information,rendering them a vital issue in the practical application of autonomous driving.To address the traffic challenges,this work focused on complex roundabouts with multi-lane and proposed a Perception EnhancedDeepDeterministic Policy Gradient(PE-DDPG)for AutonomousDriving in the Roundabouts.Specifically,themodel incorporates an enhanced variational autoencoder featuring an integrated spatial attention mechanism alongside the Deep Deterministic Policy Gradient framework,enhancing the vehicle’s capability to comprehend complex roundabout environments and make decisions.Furthermore,the PE-DDPG model combines a dynamic path optimization strategy for roundabout scenarios,effectively mitigating traffic bottlenecks and augmenting throughput efficiency.Extensive experiments were conducted with the collaborative simulation platform of CARLA and SUMO,and the experimental results show that the proposed PE-DDPG outperforms the baseline methods in terms of the convergence capacity of the training process,the smoothness of driving and the traffic efficiency with diverse traffic flow patterns and penetration rates of autonomous vehicles(AVs).Generally,the proposed PE-DDPGmodel could be employed for autonomous driving in complex scenarios with imperfect data. 展开更多
关键词 autonomous driving traffic roundabouts deep deterministic policy gradient spatial attention mechanisms
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Modeling and TOPSIS-GRA Algorithm for Autonomous Driving Decision-Making Under 5G-V2X Infrastructure
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作者 Shijun Fu Hongji Fu 《Computers, Materials & Continua》 SCIE EI 2023年第4期1051-1071,共21页
This paper is to explore the problems of intelligent connected vehicles(ICVs)autonomous driving decision-making under a 5G-V2X structured road environment.Through literature review and interviews with autonomous drivi... This paper is to explore the problems of intelligent connected vehicles(ICVs)autonomous driving decision-making under a 5G-V2X structured road environment.Through literature review and interviews with autonomous driving practitioners,this paper firstly puts forward a logical framework for designing a cerebrum-like autonomous driving system.Secondly,situated on this framework,it builds a hierarchical finite state machine(HFSM)model as well as a TOPSIS-GRA algorithm for making ICV autonomous driving decisions by employing a data fusion approach between the entropy weight method(EWM)and analytic hierarchy process method(AHP)and by employing a model fusion approach between the technique for order preference by similarity to an ideal solution(TOPSIS)and grey relational analysis(GRA).The HFSM model is composed of two layers:the global FSM model and the local FSM model.The decision of the former acts as partial input information of the latter and the result of the latter is sent forward to the local pathplanning module,meanwhile pulsating feedback to the former as real-time refresh data.To identify different traffic scenarios in a cerebrum-like way,the global FSM model is designed as 7 driving behavior states and 17 driving characteristic events,and the local FSM model is designed as 16 states and 8 characteristic events.In respect to designing a cerebrum-like algorithm for state transition,this paper firstly fuses AHP weight and EWM weight at their output layer to generate a synthetic weight coefficient for each characteristic event;then,it further fuses TOPSIS method and GRA method at the model building layer to obtain the implementable order of state transition.To verify the feasibility,reliability,and safety of theHFSMmodel aswell as its TOPSISGRA state transition algorithm,this paper elaborates on a series of simulative experiments conducted on the PreScan8.50 platform.The results display that the accuracy of obstacle detection gets 98%,lane line prediction is beyond 70 m,the speed of collision avoidance is higher than 45 km/h,the distance of collision avoidance is less than 5 m,path planning time for obstacle avoidance is averagely less than 50 ms,and brake deceleration is controlled under 6 m/s2.These technical indexes support that the driving states set and characteristic events set for the HFSM model as well as its TOPSIS-GRA algorithm may bring about cerebrum-like decision-making effectiveness for ICV autonomous driving under 5G-V2X intelligent road infrastructure. 展开更多
关键词 5G-V2X cerebrum-like autonomous driving driving behavior decision-making hierarchical finite state machines TOPSIS-GRA algorithm
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Parallel Planning:A New Motion Planning Framework for Autonomous Driving 被引量:9
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作者 Long Chen Xuemin Hu +3 位作者 Wei Tian Hong Wang Dongpu Cao Fei-Yue Wang 《IEEE/CAA Journal of Automatica Sinica》 EI CSCD 2019年第1期236-246,共11页
Motion planning is one of the most significant technologies for autonomous driving. To make motion planning models able to learn from the environment and to deal with emergency situations, a new motion planning framew... Motion planning is one of the most significant technologies for autonomous driving. To make motion planning models able to learn from the environment and to deal with emergency situations, a new motion planning framework called as"parallel planning" is proposed in this paper. In order to generate sufficient and various training samples, artificial traffic scenes are firstly constructed based on the knowledge from the reality.A deep planning model which combines a convolutional neural network(CNN) with the Long Short-Term Memory module(LSTM) is developed to make planning decisions in an end-toend mode. This model can learn from both real and artificial traffic scenes and imitate the driving style of human drivers.Moreover, a parallel deep reinforcement learning approach is also presented to improve the robustness of planning model and reduce the error rate. To handle emergency situations, a hybrid generative model including a variational auto-encoder(VAE) and a generative adversarial network(GAN) is utilized to learn from virtual emergencies generated in artificial traffic scenes. While an autonomous vehicle is moving, the hybrid generative model generates multiple video clips in parallel, which correspond to different potential emergency scenarios. Simultaneously, the deep planning model makes planning decisions for both virtual and current real scenes. The final planning decision is determined by analysis of real observations. Leveraging the parallel planning approach, the planner is able to make rational decisions without heavy calculation burden when an emergency occurs. 展开更多
关键词 autonomous driving artificial traffic SCENE deep learning EMERGENCIES motion PLANNING PARALLEL PLANNING
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Location estimation of autonomous driving robot and 3D tunnel mapping in underground mines using pattern matched LiDAR sequential images 被引量:1
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作者 Heonmoo Kim Yosoon Choi 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2021年第5期779-788,共10页
In this study,a machine vision-based pattern matching technique was applied to estimate the location of an autonomous driving robot and perform 3D tunnel mapping in an underground mine environment.The autonomous drivi... In this study,a machine vision-based pattern matching technique was applied to estimate the location of an autonomous driving robot and perform 3D tunnel mapping in an underground mine environment.The autonomous driving robot continuously detects the wall of the tunnel in the horizontal direction using the light detection and ranging(Li DAR)sensor and performs pattern matching by recognizing the shape of the tunnel wall.The proposed method was designed to measure the heading of the robot by fusion with the inertial measurement units sensor according to the pattern matching accuracy;it is combined with the encoder sensor to estimate the location of the robot.In addition,when the robot is driving,the vertical direction of the underground mine is scanned through the vertical Li DAR sensor and stacked to create a 3D map of the underground mine.The performance of the proposed method was superior to that of previous studies;the mean absolute error achieved was 0.08 m for the X-Y axes.A root mean square error of 0.05 m^(2)was achieved by comparing the tunnel section maps that were created by the autonomous driving robot to those of manual surveying. 展开更多
关键词 Pattern matching Location estimation autonomous driving robot 3D tunnel mapping Underground mine
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On Cognitive Style in English Web-based Autonomous Learning
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作者 刘茜 《海外英语》 2014年第21期57-58,65,共3页
Since Henry Holec first put forward the term‘Autonomy'in 1980's, autonomous learning has been drawing the universal attention of scholars both at home and abroad. Promoting learners' ability of self-regul... Since Henry Holec first put forward the term‘Autonomy'in 1980's, autonomous learning has been drawing the universal attention of scholars both at home and abroad. Promoting learners' ability of self-regulated learning has been taken as one of the important goals of modern education. College English autonomous learning based on network environment does not mean free study without any restraints or monitoring, but rather involves the self-monitoring and external monitoring. Meanwhile, different learners may have different cognitive styles in their learning processes, which may have an influence on the improvement of the learners' efficiency in the autonomous language learning. Proper monitoring models coordinating with the students' different field cognitive styles. 展开更多
关键词 ENGLISH WEB-BASED autonomous LEARNING FIELD cognit
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Cooperative Intelligence for Autonomous Driving
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作者 CHENG Xiang DUAN Dongliang +1 位作者 YANG Liuqing ZHENG Nanning 《ZTE Communications》 2019年第2期44-50,共7页
Autonomous driving is an emerging technology attracting interests from various sectors in recent years.Most of existing work treats autonomous vehicles as isolated individuals and has focused on developing separate in... Autonomous driving is an emerging technology attracting interests from various sectors in recent years.Most of existing work treats autonomous vehicles as isolated individuals and has focused on developing separate intelligent modules.In this paper,we attempt to exploit the connectivity among vehicles and propose a systematic framework to develop autonomous driving techniques.We first introduce a general hierarchical information fusion framework for cooperative sensing to obtain global situational awareness for vehicles.Following this,a cooperative intelligence framework is proposed for autonomous driving systems.This general framework can guide the development of data collection,sharing and processing strategies to realize different intelligent functions in autonomous driving. 展开更多
关键词 autonomous driving COOPERATIVE INTELLIGENCE information FUSION vehicular COMMUNICATIONS and NETWORKING
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A Probabilistic Architecture of Long-Term Vehicle Trajectory Prediction for Autonomous Driving
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作者 Jinxin Liu Yugong Luo +3 位作者 Zhihua Zhong Keqiang Li Heye Huang Hui Xiong 《Engineering》 SCIE EI CAS 2022年第12期228-239,共12页
In mixed and dynamic traffic environments,accurate long-term trajectory forecasting of surrounding vehicles is one of the indispensable preconditions for autonomous vehicles to accomplish reasonable behavioral decisio... In mixed and dynamic traffic environments,accurate long-term trajectory forecasting of surrounding vehicles is one of the indispensable preconditions for autonomous vehicles to accomplish reasonable behavioral decisions and guarantee driving safety.In this paper,we propose an integrated probabilistic architecture for long-term vehicle trajectory prediction,which consists of a driving inference model(DIM)and a trajectory prediction model(TPM).The DIM is designed and employed to accurately infer the potential driving intention based on a dynamic Bayesian network.The proposed DIM incorporates the basic traffic rules and multivariate vehicle motion information.To further improve the prediction accuracy and realize uncertainty estimation,we develop a Gaussian process-based TPM,considering both the short-term prediction results of the vehicle model and the driving motion characteristics.Afterward,the effectiveness of our novel approach is demonstrated by conducting experiments on a public naturalistic driving dataset under lane-changing scenarios.The superior performance on the task of long-term trajectory prediction is presented and verified by comparing with other advanced methods. 展开更多
关键词 autonomous driving Dynamic Bayesian network driving intention recognition Gaussian process Vehicle trajectory prediction
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Cognitive Supervisor for an Autonomous Swarm of Robots 被引量:1
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作者 Vladimir G.Ivancevic Darryn J.Reid 《Intelligent Control and Automation》 2017年第1期44-65,共22页
As a sequel to our recent work [1], in which a control framework was developed for large-scale joint swarms of unmanned ground (UGV) and aerial (UAV) vehicles, the present paper proposes cognitive and meta-cognitive s... As a sequel to our recent work [1], in which a control framework was developed for large-scale joint swarms of unmanned ground (UGV) and aerial (UAV) vehicles, the present paper proposes cognitive and meta-cognitive supervisor models for this kind of distributed robotic system. The cognitive supervisor model is a formalization of the recently Nobel-awarded research in brain science on mammalian and human path integration and navigation, performed by the hippocampus. This is formalized here as an adaptive Hamiltonian path integral, and efficiently simulated for implementation on robotic vehicles as a pair of coupled nonlinear Schr?dinger equations. The meta-cognitive supervisor model is a modal logic of actions and plans that hinges on a weak causality relation that specifies when atoms may change their values without specifying that they must change. This relatively simple logic is decidable yet sufficiently expressive to support the level of inference needed in our application. The atoms and action primitives of the logic framework also provide a straight-forward way of connecting the meta-cognitive supervisor with the cognitive supervisor, with other modules, and to the meta-cognitive supervisors of other robotic platforms in the swarm. 展开更多
关键词 autonomous Robotic Swarm cognitive Supervisor Hippocampus Path Integration and Navigation Hamiltonian Path Integral Modal Logic Nonlinear Schrodinger Equation Reasoning about Actions and Plans
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Generating routes for autonomous driving in vehicle-to-infrastructure communications
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作者 Jianjun Yang Tinggui Chen +3 位作者 Bryson Payne Ping Guo Yanping Zhang Juan Guo 《Digital Communications and Networks》 SCIE 2020年第4期444-451,共8页
The study of vehicular networks has attracted considerable interest in academia and the industry.In the broad area,connected vehicles and autonomous driving are technologies based on wireless data communication betwee... The study of vehicular networks has attracted considerable interest in academia and the industry.In the broad area,connected vehicles and autonomous driving are technologies based on wireless data communication between vehicles or between vehicles and infrastructures.A Vehicle-to-Infrastructure(V2I)system consists of communications and computing over vehicles and related infrastructures.In such a system,wireless sensors are installed in some selected points along roads or driving areas.In autonomous driving,it is crucial for a vehicle to figure out the ideal routes by the communications between its equipped sensors and infrastructures then the vehicle is automatically moving along the routes.In this paper,we propose a Bezier curve based recursive algorithm,which effectively creates routes for vehicles through the communication between the On-Board Unit(OBU)and the Road-Side Units(RSUs).In addition,this approach generates a very low overhead.We conduct simulations to test the proposed algorithm in various situations.The experiment results demonstrate that our algorithm creates almost ideal routes. 展开更多
关键词 autonomous driving Vehicles and infrastructures Bezier curve Recursive algorithm On board unit Road side unit
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Effect of Cognitive Impairment on Driving-Relevant Cognition in Older Persons
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作者 Rahel Bieri Michael Jager +3 位作者 Nora Bethencourt Urs Peter Mosimann Rene Martin Mari Tobias Nef 《Journal of Traffic and Transportation Engineering》 2014年第1期11-18,共8页
Intact cognitive abilities are fundamental for driving. Driving-relevant cognition may be affected in older drivers due to aging or cognitive impairment. The aim of this study was to investigate the effects of cogniti... Intact cognitive abilities are fundamental for driving. Driving-relevant cognition may be affected in older drivers due to aging or cognitive impairment. The aim of this study was to investigate the effects of cognitive impairment on driving-relevant cognition in older persons. Performance in selective and divided attention, eye-hand-coordination, executive functions and the ability to regulate distance and speed of 18 older persons with CI-Group (cognitive impairment group) was compared to performance of older control group (18 age and gender-matched cognitively normal subjects) and young control group (18 gender-matched young subjects). The CI-Group showed poorer performance than the other two control groups in all cognitive tasks (significance level (p) 〈 0.001, effect size (partial r/e) = 0.63). Differences between cognitively impaired and cognitively normal subjects were still significant after controlling for age (effect sizes from 0.14 to 0.28). Dual tasking affected performance of cognitively impaired subjects more than performance of the other two groups (p = 0.016, partial η2 = 0.14). Results show that cognitive impairment has age-independent detrimental effects on selective and divided attention, eye-hand-coordination, executive functions and the ability to regulate distance and speed. Largest effect sizes are found for reaction times in attention tasks. 展开更多
关键词 cognitive impairment aging driving cognition cognitive assessment age differences.
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Human-Like Decision-Making of Autonomous Vehicles in Dynamic Traffic Scenarios
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作者 Tangyike Zhang Junxiang Zhan +2 位作者 Jiamin Shi Jingmin Xin Nanning Zheng 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2023年第10期1905-1917,共13页
With the maturation of autonomous driving technology, the use of autonomous vehicles in a socially acceptable manner has become a growing demand of the public. Human-like autonomous driving is expected due to the impa... With the maturation of autonomous driving technology, the use of autonomous vehicles in a socially acceptable manner has become a growing demand of the public. Human-like autonomous driving is expected due to the impact of the differences between autonomous vehicles and human drivers on safety.Although human-like decision-making has become a research hotspot, a unified theory has not yet been formed, and there are significant differences in the implementation and performance of existing methods. This paper provides a comprehensive overview of human-like decision-making for autonomous vehicles. The following issues are discussed: 1) The intelligence level of most autonomous driving decision-making algorithms;2) The driving datasets and simulation platforms for testing and verifying human-like decision-making;3) The evaluation metrics of human-likeness;personalized driving;the application of decisionmaking in real traffic scenarios;and 4) The potential research direction of human-like driving. These research results are significant for creating interpretable human-like driving models and applying them in dynamic traffic scenarios. In the future, the combination of intuitive logical reasoning and hierarchical structure will be an important topic for further research. It is expected to meet the needs of human-like driving. 展开更多
关键词 autonomous vehicles DECISION-MAKING driving behavior human-like driving
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DQL-Based Intelligent Scheduling Algorithm for Automatic Driving in Massive MIMO V2I Scenarios
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作者 Yong Liao Zisong Yin +1 位作者 Zhijing Yang Xuanfan Shen 《China Communications》 SCIE CSCD 2023年第3期18-26,共9页
Connected and autonomous vehicle(CAV)vehicle to infrastructure(V2I)scenarios have more stringent requirements on the communication rate,delay,and reliability of the Internet of vehicles(Io V).New radio vehicle to ever... Connected and autonomous vehicle(CAV)vehicle to infrastructure(V2I)scenarios have more stringent requirements on the communication rate,delay,and reliability of the Internet of vehicles(Io V).New radio vehicle to everything(NR-V2X)adopts link adaptation(LA)to improve the efficiency and reliability of road safety information transmission.In order to solve the problem that the existing LA scheduling algorithms cannot adapt to the Doppler shift and complex fast time-varying channel in V2I scenario,resulting in low reliability of information transmission,this paper proposes a deep Q-learning(DQL)-based massive multiple-input multiple-output(MIMO)LA scheduling algorithm for autonomous driving V2I scenario.The algorithm combines deep neural network(DNN)with Q-learning(QL)algorithm,which is used for joint scheduling of modulation and coding scheme(MCS)and space division multiplexing(SDM).The system simulation results show that the algorithm proposed in this paper can fully adapt to the different channel environment in the V2I scenario,and select the optimal MCS and SDM for the transmission of road safety information,thereby the accuracy of road safety information transmission is improved,collision accidents can be avoided,and bring a good autonomous driving experience. 展开更多
关键词 NR autonomous driving V2I link adap-tation massive MIMO deep Q-learning
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Behavior Analysis of Self-Driving Tourists Based on Content Analysis of Network Travel Notes: A Case Study of the Inner Mongolia Autonomous Region
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作者 HAN Dong TANG Jia +1 位作者 HUANG Lihua JIA Lei 《Journal of Landscape Research》 2018年第4期138-144,共7页
Self-driving tour is one of the most important ways for people to travel, and network travel notes actually reflect the traveling information of self-driving tourists. In this paper, with the network travel notes of s... Self-driving tour is one of the most important ways for people to travel, and network travel notes actually reflect the traveling information of self-driving tourists. In this paper, with the network travel notes of self-driving tourists as the research object, methods such as text analysis and visualization were adopted to study behavior patterns of self-driving tourists, tourism experience,time-space migration, and distribution of tourism resources in Inner Mongolia, from the multiple dimensions of mobile drivers,perceived dimensions, and spatial migration. The results showed that: ① self-driving tourists had a variety of motivations for traveling, in which love for nature dominated; ② self-driving tour destinations were mainly Hulunbuir,Ordos,and Alxa League;③ spatial migration was characterized by obvious seasonal fluctuations. The research on the behavior of self-driving tourists in Inner Mongolia is an important part for the study of the connection between tourism resources and market connection in Inner Mongolia, and is of significance for guiding the theory, practice and policy formulation of self-driving tours in Inner Mongolia. 展开更多
关键词 自助旅游 中国 发展现状 自驾车
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IoV and Blockchain-Enabled Driving Guidance Strategy in Complex Traffic Environment
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作者 Yuchuan Fu Changle Li +1 位作者 Tom H.Luan Yao Zhang 《China Communications》 SCIE CSCD 2023年第12期230-243,共14页
Diversified traffic participants and complex traffic environment(e.g.,roadblocks or road damage exist)challenge the decision-making accuracy of a single connected and autonomous vehicle(CAV)due to its limited sensing ... Diversified traffic participants and complex traffic environment(e.g.,roadblocks or road damage exist)challenge the decision-making accuracy of a single connected and autonomous vehicle(CAV)due to its limited sensing and computing capabilities.Using Internet of Vehicles(IoV)to share driving rules between CAVs can break limitations of a single CAV,but at the same time may cause privacy and safety issues.To tackle this problem,this paper proposes to combine IoV and blockchain technologies to form an efficient and accurate autonomous guidance strategy.Specifically,we first use reinforcement learning for driving decision learning,and give the corresponding driving rule extraction method.Then,an architecture combining IoV and blockchain is designed to ensure secure driving rule sharing.Finally,the shared rules will form an effective autonomous driving guidance strategy through driving rules selection and action selection.Extensive simulation proves that the proposed strategy performs well in complex traffic environment,mainly in terms of accuracy,safety,and robustness. 展开更多
关键词 autonomous driving guidance blockchain communication range Internet of Vehicles reinforcement learning
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基于平行测试的认知自动驾驶智能架构研究
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作者 王晓 张翔宇 +4 位作者 周锐 田永林 王建功 陈龙 孙长银 《自动化学报》 EI CAS CSCD 2024年第2期356-371,共16页
在大数据、云计算和机器学习等新一代人工智能技术的推动下,自动驾驶的感知智能在近年来得到显著的提升与发展.然而,与人类驾驶过程中隐含的以自我目的实现为引导的自探索性和自主性相比,现阶段自动驾驶技术主要以辅助驾驶功能为主,还... 在大数据、云计算和机器学习等新一代人工智能技术的推动下,自动驾驶的感知智能在近年来得到显著的提升与发展.然而,与人类驾驶过程中隐含的以自我目的实现为引导的自探索性和自主性相比,现阶段自动驾驶技术主要以辅助驾驶功能为主,还停留在以被动感知、规划与控制为主的初级智能自动驾驶阶段.为实现车辆智能从数据驱动的环境感知、辅助决策、被动规划到知识驱动的场景认知、推理决策、主动规划的提升,亟需增强车辆自身对复杂外界信息归纳提炼、推理决策、评价估计等类人能力.首先回顾自动驾驶关键技术演化及其应用发展历程;随后分析测试对车辆智能评估的效用;然后基于平行测试理论,提出自动驾驶车辆认知智能训练、测试与评估空间的构建方法,并设计基于平行测试的认知自动驾驶智能训练框架.该项研究工作预期能为推动自动驾驶从感知智能向认知智能的升级提供可行的技术支撑与实现路径. 展开更多
关键词 认知自动驾驶 平行测试 平行驾驶 车辆认知智能
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机耕道自动驾驶农机局部路径规划
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作者 杨丽丽 唐晓宇 +3 位作者 吴思贤 文龙 杨卫中 吴才聪 《农业工程学报》 EI CAS CSCD 2024年第1期27-36,共10页
针对机耕道场景下自动驾驶农机行驶的安全性、平稳性与规划实时性的实际需求,该研究提出了一种基于二次规划的局部路径规划方法。首先基于有限状态机构建农机机耕道行驶模式,其次采用横纵向解耦的方法,通过改进状态栅格法分别对农机速... 针对机耕道场景下自动驾驶农机行驶的安全性、平稳性与规划实时性的实际需求,该研究提出了一种基于二次规划的局部路径规划方法。首先基于有限状态机构建农机机耕道行驶模式,其次采用横纵向解耦的方法,通过改进状态栅格法分别对农机速度行为和轨迹行为进行决策,随后利用二次规划方法生成满足多目标、多约束条件的农机轨迹和速度,得到最优路径,最后在多种行驶环境中进行仿真和实车试验,行驶参考速度为2 m/s。实车试验结果表明,在绕行静态障碍物场景中,规划轨迹的平均绝对曲率为0.021 m^(-1),最大绝对曲率为0.056 m^(-1),平均绝对横向误差为3.23 cm,最大绝对横向误差为8.69 cm,农机与障碍物外轮廓的距离大于0.76 m;在规避相向行驶、同向行驶和横穿机耕道的动态障碍物场景中,规划速度的平均绝对速度误差为0.08~0.12 m/s,绝对速度误差小于0.38 m/s,加速度变化范围为-0.38~0.44 m/s^(2)。在规划周期为200 ms的仿真试验中,该文算法平均耗时48 ms,最大耗时75 ms,相比采用静态状态栅格法平均耗时减少38 ms,算法效率提升44%。研究结果可为机耕道场景下的农机局部路径规划提供技术支持。 展开更多
关键词 农业机械 自动驾驶 局部路径规划 二次规划 有限状态机
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超高速公路自动驾驶车辆换道轨迹规划策略
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作者 何永明 邢婉钰 +1 位作者 魏堃 吴佳璇 《华南理工大学学报(自然科学版)》 EI CAS CSCD 2024年第4期104-113,共10页
为提高自动驾驶车辆在超高速公路行驶的安全性,提出了一种换道轨迹规划策略。首先,采用5次多项式生成一般变道轨迹簇,以车辆动力学极限和周围交通车辆为约束,将轨迹规划问题量化为求解换道行为持续时间;接着,考虑车辆动力学约束,建立了... 为提高自动驾驶车辆在超高速公路行驶的安全性,提出了一种换道轨迹规划策略。首先,采用5次多项式生成一般变道轨迹簇,以车辆动力学极限和周围交通车辆为约束,将轨迹规划问题量化为求解换道行为持续时间;接着,考虑车辆动力学约束,建立了车辆动力学模型和Brush轮胎模型,基于所建立汽车模型的轮胎侧向力数据求解轮胎侧偏刚度,辅以魔术轮胎模型,验证所求轮胎侧偏刚度;然后,引入质心侧偏角-横摆角速度相平面,得到高速车辆安全驾驶包络线,并给定多组车速和附着系数进行CarSim仿真训练,确定满足车辆动力学约束的最短换道时间;最后,考虑与周围交通车辆的避撞约束,分析3种典型的换道场景,基于单障碍车的位置,确定满足避撞要求的最短与最长换道持续时间,建立满足安全换道要求的换道持续时间阈值模型。经多参数安全换道域检验,所建立的车辆安全换道持续时间边界模型能够在给定参数下求解出安全可行的换道轨迹,为超高速公路换道行为提供轨迹参考,提高超高速公路换道行为的安全性。 展开更多
关键词 自动驾驶 转向稳定性 轨迹规划 超高速公路 建模仿真
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AF-CenterNet:基于交叉注意力机制的毫米波雷达和相机融合的目标检测
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作者 车俐 吕连辉 蒋留兵 《计算机应用研究》 CSCD 2024年第4期1258-1263,共6页
对于自动驾驶领域而言,确保在各种天气和光照条件下精确检测其他车辆目标是至关重要的。针对单个传感器获取信息的局限性,提出一种基于cross-attention注意力机制的融合方法(AF),用于在特征层面上融合毫米波雷达和相机信息。首先,将毫... 对于自动驾驶领域而言,确保在各种天气和光照条件下精确检测其他车辆目标是至关重要的。针对单个传感器获取信息的局限性,提出一种基于cross-attention注意力机制的融合方法(AF),用于在特征层面上融合毫米波雷达和相机信息。首先,将毫米波雷达和相机进行空间对齐,并将对齐后的点云信息投影成点云图像。然后,将点云图像在高度和宽度方向上进行扩展,以提高相机图像和点云图像之间的匹配度。最后,将点云图像和相机图像送入包含AF结构的CenterNet目标检测网络中进行训练,并生成一个空间注意力权重,以增强相机中的关键特征。实验结果表明,AF结构可以提高原网络检测各种大小目标的性能,特别是对小目标的检测提升更为明显,且对系统的实时性影响不大,是提高车辆在多种场景下检测精度的理想选择。 展开更多
关键词 自动驾驶 目标检测 毫米波雷达 交叉注意力融合
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基于柔性演员-评论家算法的决策规划协同研究
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作者 唐斌 刘光耀 +3 位作者 江浩斌 田宁 米伟 王春宏 《交通运输系统工程与信息》 EI CSCD 2024年第2期105-113,187,共10页
为了解决基于常规深度强化学习(Deep Reinforcement Learning, DRL)的自动驾驶决策存在学习速度慢、安全性及合理性较差的问题,本文提出一种基于柔性演员-评论家(Soft Actor-Critic,SAC)算法的自动驾驶决策规划协同方法,并将SAC算法与... 为了解决基于常规深度强化学习(Deep Reinforcement Learning, DRL)的自动驾驶决策存在学习速度慢、安全性及合理性较差的问题,本文提出一种基于柔性演员-评论家(Soft Actor-Critic,SAC)算法的自动驾驶决策规划协同方法,并将SAC算法与基于规则的决策规划方法相结合设计自动驾驶决策规划协同智能体。结合自注意力机制(Self Attention Mechanism, SAM)和门控循环单元(Gate Recurrent Unit, GRU)构建预处理网络;根据规划模块的具体实现方式设计动作空间;运用信息反馈思想设计奖励函数,给智能体添加车辆行驶条件约束,并将轨迹信息传递给决策模块,实现决策规划的信息协同。在CARLA自动驾驶仿真平台中搭建交通场景对智能体进行训练,并在不同场景中将所提出的决策规划协同方法与常规的基于SAC算法的决策规划方法进行比较,结果表明,本文所设计的自动驾驶决策规划协同智能体学习速度提高了25.10%,由其决策结果生成的平均车速更高,车速变化率更小,更接近道路期望车速,路径长度与曲率变化率更小。 展开更多
关键词 智能交通 自动驾驶 柔性演员-评论家算法 决策规划协同 深度强化学习
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不同草原防火政策下内蒙古草原火灾发生风险及其驱动因素的研究
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作者 张恒 诺敏 +4 位作者 班擎宇 赵鹏武 常禹 弥宏卓 殷继艳 《中国草地学报》 CSCD 2024年第4期100-111,共12页
草原火灾是草原生态系统中重要的干扰因子之一,不同时期的草原防火政策可能会导致草原火灾发生概率及驱动因素发生变化。本研究基于内蒙古1981~2020年草原火灾数据,以新旧《草原防火条例》实施时间(旧《草原防火条例》1993年10月5日颁... 草原火灾是草原生态系统中重要的干扰因子之一,不同时期的草原防火政策可能会导致草原火灾发生概率及驱动因素发生变化。本研究基于内蒙古1981~2020年草原火灾数据,以新旧《草原防火条例》实施时间(旧《草原防火条例》1993年10月5日颁布并实施,新《草原防火条例》2008年11月19日颁布并于2009年1月1日起实施)为界线,通过随机森林模型分4个时期(1981~2020年、1981~1993年、1994~2008年、2009~2020年)对内蒙古草原火灾发生概率与驱动因素进行比较与分析,并绘制草原火灾风险等级区划图。结果表明:(1)4个时期建模的全样本AUC在0.930~0.940之间,精度优异。(2)在不同时期,气象因素(日平均相对湿度、气温日较差等)始终是影响草原火灾的主导因素,海拔、距火点最近公路距离等因素也是内蒙古草原火灾发生的重要驱动因素;(3)1981~1993年和1981~2020年草原火灾风险区基本相似,中、高、极高草原火灾风险区主要集中在呼伦贝尔市大部分地区和兴安盟北部,1994~2008年中、高、极高草原火灾风险区主要集中在呼伦贝尔市,而2009~2020年中、高、极高草原火灾风险区主要集中在呼伦贝尔市西部、锡林郭勒盟北部、阿拉善盟东南部、乌海市和鄂尔多斯市东部。 展开更多
关键词 内蒙古自治区 草原火灾 草原防火条例 驱动因素 火灾风险区划
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