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地下停车场环境融合语义特征的视觉惯性定位方法

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湖南大学学报（自然科学版） 2024年第8期51卷 185-197页

作者：秦兆博李琦邢喆高铭谢国涛王晓伟湖南大学机械与运载工程学院湖南长沙410082 湖南大学无锡智能控制研究院江苏无锡214115

针对地下停车场环境GPS信号差、光线暗、特征少、纹理弱等带来的定位问题,提出了一种融合语义信息的视觉惯性定位算法.该算法首先通过视觉里程计和IMU预积分进行视觉惯性信息的融合.同时,利用4个鱼眼摄像头输入图像构建全景环视图像,并... 详细信息

针对地下停车场环境GPS信号差、光线暗、特征少、纹理弱等带来的定位问题,提出了一种融合语义信息的视觉惯性定位算法.该算法首先通过视觉里程计和IMU预积分进行视觉惯性信息的融合.同时,利用4个鱼眼摄像头输入图像构建全景环视图像,并采用语义分割算法提取停车场环境语义信息.然后,根据视觉惯性紧耦合位姿完成逆投影变换,获得语义特征投影地图并采用回环检测和位姿图优化方式减小累积误差,完成全局位姿图优化,实现较高精度的定位效果.最后,通过Gazebo仿真与实车测试对该算法进行了验证.结果表明,本文算法能充分利用环境语义信息构建较为完整的语义地图,且基于重复定位误差对比,相较于ORB-SLAM3提高了车辆定位精度.

关键词：自主代客泊车视觉惯性定位多鱼眼全景环视语义地图

Autonomous parking control for intelligent vehicles based on a novel algorithm

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The Journal of China Universities of Posts and Telecommunications 2017年第4期24卷 51-56页

作者： Gao Hongbo xie guotao Zhang Xinyu Cheng Bo State Key Laboratory of Automotive Safety and Energy Tsinghua University Beijing 100084 China Information Technology Center Tsinghua University Beijing 100084 China

Along with the increasing number of vehicles, parking space becomes narrow gradually, safety parking puts forward higher requirements on the driver＇s driving technology. How to safely, quickly and accurately park the vehiclo to parking space right？ This paper presents an automatic parking scheme based on trajectory planning, which analyzing the mechanical model oftbe vehicle, establishing vehicle steering model and parking model, coming to the conclusion that it is the turning radius is independent of the vehicle speed at low speed. The Matlab simulation environment verifies the correctness and effectiveness of the proposed algorithm for parking. A class of the automatic parking problem of intelligent vehicles is solved.

关键词： intelligent vehicles control algorithm autonomous parking

Lateral control of autonomous vehicles based on learning driver behavior via cloud model

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The Journal of China Universities of Posts and Telecommunications 2017年第2期24卷 10-17页

作者： Gao Hongbo xie guotao Liu Hongzhe Zhang Xinyu Li Deyi State Key Laboratory of Automotive Safety and Energy Tsinghua University Beijing Key Laboratory of Information Service Engineering Beijing Union University Information Technology Center Tsinghua University The 61th Institute of Electronic System Engineering

In order to achieve the lateral control of the intelligent vehicle, use the bi-cognitive model based on cloud model and cloud reasoning, solve the decision problem of the qualitative and quantitative of the lateral control of the intelligent vehicle. Obtaining a number of experiment data by driving a vehicle, classify the data according to the concept of data and fix the input and output variables of the cloud controller, design the control rules of the cloud controller of intelligent vehicle, and clouded and fix the parameter of cloud controller： expectation, entropy and hyper entropy. In order to verify the effectiveness of the cloud controller, joint simulation platform based on Matlab/Simulink/CarSim is established. Experimental analysis shows that： driver＇s lateral controller based on cloud model is able to achieve tracking of the desired angle, and achieve good control effect, it also verifies that a series of mental activities such as feeling, cognition, calculation, decision and so on are fuzzy and uncertain.

关键词： cloud model driver behavior autonomous vehicles lateral control

Finite-time Platoon Control of Connected and Automated Vehicles with Mismatched Disturbances

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Finite-time Platoon Control of Connected and Automated Vehic...

Mass extinctions, their causes and consequences: an interview with Douglas *** and Shuzhong Shen

第三十九届中国控制会议

作者： Xuan Wang Yougang Bian Xiaohui Qin Manjiang Hu Biao Xu guotao xie College of Mechanical and Vehicle Engineering Hunan University School of Vehicle and Mobility Tsinghua University

Platoon control is a promising approach for connected and automated vehicles（CAVs） to reduce traffic pressure. This paper studies finite-time platoon control of CAVs subject to mismatched as well as matched disturbances. A finite-time disturbance observer（DO） is first designed to estimate the mismatched velocity disturbance and the matched acceleration disturbance, and a sliding mode controller is then proposed based on the observed vehicle states for longitudinal cooperation of CAVs. Furthermore, it is proved that the desired platoon formation can be achieved in finite time. Finally, a simulation study is conducted to verify the theoretical results. Compared with a benchmark linear controller, the proposed finite-time platoon controller has more reliable performance.

关键词： Connected and automated vehicles(CAVs) platoon control mismatched disturbances disturbance observer

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National Science Review 2024年第1期11卷 66-70页

作者： Shucheng xie State Key Laboratory of Biogeology and Environmental Geology China University of Geosciences at Wuhan

‘Mass extinctions’ have been a hot topic for several decades. What triggers a mass extinction? How does a mass extinction impact the evolution of life? How does our ecosystem recover after a mass extinction? These questions attracted the interest of both scientists and the public *** spoke to two renowned researchers in the field of mass extinctions: Prof. Douglas H. Erwin from the National Museum of Natural History of the USA, and Prof. Shuzhong Shen from Nanjing University, China.

关键词： Stratigraphy

Turbulence Statistics of Thermo-Buoyancy Supercritical Fuel Flow in a Regenerative Cooling Channel

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Journal of Thermal Science 2024年第1期33卷 126-137页

作者： SUN Feng xie Gongnan School of Marine Science and Technology Northwestern Polytechnical UniversityXi'an 710072China Department of Thermal Engineering Tsinghua UniversityBeijing 100084China

Active regenerative cooling with supercritical hydrocarbon fuel is considered as the most promising thermal protection *** existence of buoyancy force would lead to strongly anisotropic flow and thermal transport *** is closely related to the cooling performance of the *** elucidate the mechanisms of turbulent transport,the large eddy simulation(LES) was performed to assess turbulence statistics within different turbulence *** results indicated that the buoyancy and inertial force together dominated the change of turbulent ***,the spatial thermal buoyancy effect significantly suppressed the vertical velocity *** is due to the laminar motion caused by the buoyancy force,thereby weakening the thermal *** the statistics of velocity fluctuation,it was found that the buoyancy force and inertial force greatly weaken the vertical and streamwise velocity fluctuation,*** the statistics of thermal transport,the results pointed out that the near-wall heat transport characteristics need to be paid more *** thickness of the temperature mixing boundary layer led to the attenuation of vertical heat flux,which inhibited vertical temperature diffusion and predisposed to extreme conditions of heat transfer *** results can enhance the academic understanding of the heat transfer mechanism of supercritical fluids,and give guidance for further applications of thermal protection.

关键词： active regenerative cooling large eddy simulation(LES) buoyancy force turbulence statistics

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严格避撞的车辆队列分布式鲁棒控制

汽车工程 2020年第10期42卷 1312-1319页

作者：杨泽宇黄晋胡展溢谢国涛钟志华清华大学车辆与运载学院北京100084 中国工程院北京100088

针对智能网联车辆队列控制问题,提出一种严格避撞的分布式鲁棒控制器设计方法。建立了包含复杂不确定性与外部干扰的非线性误差动力学模型。通过限定车间距误差的波动区间来保证队列避撞性与紧凑性,并据此引入车间距势函数。结合车间距... 详细信息

针对智能网联车辆队列控制问题,提出一种严格避撞的分布式鲁棒控制器设计方法。建立了包含复杂不确定性与外部干扰的非线性误差动力学模型。通过限定车间距误差的波动区间来保证队列避撞性与紧凑性,并据此引入车间距势函数。结合车间距势函数、自车与邻近车辆状态和动力学不确定边界设计了分布式鲁棒控制律。从理论上证明了该控制器能保证队列的避撞性与紧凑性和车速误差的队列稳定性,并分析了通信拓扑和控制参数对控制性能的影响。通过修正期望车间距模型,控制器的应用范围可扩展到大初始误差工况。最后,通过数值仿真验证了主要理论分析结果。

关键词：车辆队列严格避撞非线性鲁棒控制队列稳定性

Output feedback stabilization of stochastic high-order planar nonlinear systems with stochastic inverse dynamics and output-constraint

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Science China(Information Sciences) 2024年第3期67卷 182-196页

作者： Ruiming xie Shengyuan XU Nanjing University of Science and Technology School of Automation

In this paper, we solve the output feedback control problem of stochastic high-order planar nonlinear systems with output constraint and stochastic integral input-to-state stability(SiISS) inverse dynamics. By employing a key coordinate transformation, a stochastic nonlinear system with output constraint and SiISS inverse dynamics is converted into an unconstrained system. By skillfully constructing an observer and adopting SiISS small-gain conditions, we develop a new output feedback control design and analysis method, and prove that all the closed-system signals are bounded almost surely, the output constraint is not violated almost surely, and the equilibrium point of the closed-loop system is stochastically asymptotically stable.

关键词： stochastic high-order planar nonlinear system outputconstraint stochastic inverse dynamics output feedbackstabilization stochastic integral input-to-state stability(SiISS)

Fixed-time stabilization of output-constrained stochastic high-order nonlinear systems

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Science China(Information Sciences) 2024年第4期67卷 5-20页

作者： Ruiming xie Shengyuan XU Nanjing University of Science and Technology School of Automation

In this study, the fixed-time stabilization problem of stochastic high-order nonlinear systems with output constraint and high-order and low-order nonlinearities is addressed. A new coordinate transformation is employed to directly convert output-constrained stochastic systems into an equivalent unconstrained *** fully extracting the characteristics of system nonlinearities and using the stochastic fixed-time stability theorem, a new design and analysis method is constructed to guarantee that the trivial solution of the closed-loop system is stochastically fixed-time stable while fulfilling the output constraint.

关键词： stochastic high-order nonlinear system outputconstraint high-order and low-order nonlinearity fixed-timestabilization finite-time stabilization