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A Hybrid Approach to Modeling and Control of Vehicle Height for Electronically Controlled Air Suspension

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Chinese Journal of Mechanical Engineering 2016年第1期29卷 152-162页

作者： sun xiaoqiang CAI Yingfeng WANG Shaohua LIU Yanling CHEN Long School of Automotive and Traffic Engineering Jiangsu University Automotive Engineering Research Institute Jiangsu University

The control problems associated with vehicle height adjustment of electronically controlled air suspension （ECAS） still pose theoretical challenges for researchers, which manifest themselves in the publications on this subject over the last years. This paper deals with modeling and control of a vehicle height adjustment system for ECAS, which is an example of a hybrid dynamical system due to the coexistence and coupling of continuous variables and discrete events. A mixed logical dynamical （MLD） modeling approach is chosen for capturing enough details of the vehicle height adjustment process. The hybrid dynamic model is constructed on the basis of some assumptions and piecewise linear approximation for components nonlinearities. Then, the on-off statuses of solenoid valves and the piecewise approximation process are described by propositional logic, and the hybrid system is transformed into the set of linear mixed-integer equalities and inequalities, denoted as MLD model, automatically by HYSDEL. Using this model, a hybrid model predictive controller （HMPC） is tuned based on online mixed-integer quadratic optimization （MIQP）. Two different scenarios are considered in the simulation, whose results verify the height adjustment effectiveness of the proposed approach. Explicit solutions of the controller are computed to control the vehicle height adjustment system in realtime using an offline multi-parametric programming technology （MPT）, thus convert the controller into an equivalent explicit piecewise affine form. Finally, bench experiments for vehicle height lifting, holding and lowering procedures are conducted, which demonstrate that the HMPC can adjust the vehicle height by controlling the on-off statuses of solenoid valves directly. This research proposes a new modeling and control method for vehicle height adjustment of ECAS, which leads to a closed-loop system with favorable dynamical properties.

关键词： electronically controlled air suspension vehicle height control hybrid system mixed logical dynamical,model predictive control

An Adaptive Nonsingular Fast Terminal Sliding Mode Control for Yaw Stability Control of Bus Based on STI Tire Model

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Chinese Journal of Mechanical Engineering 2021年第4期34卷 182-195页

作者： xiaoqiang sun Yujun Wang Yingfeng Cai Pak Kin Wong Long Chen Automotive Engineering Research Institute Jiangsu UniversityZhenjiang 212013China Department of Electromechanical Engineering University of MacaoTaipaMacaoChina State Key Laboratory of Automotive Safety and Energy Tsinghua UniversityBeijing 100084China

Due to the bus characteristics of large quality,high center of gravity and narrow wheelbase,the research of its yaw stability control(YSC)system has become the focus in the field of vehicle system ***,the tire nonlinear mechanical properties and the effectiveness of the YSC control system are not considered carefully in the current *** this paper,a novel adaptive nonsingular fast terminal sliding mode(ANFTSM)control scheme for YSC is proposed to improve the bus curve driving stability and safety on slippery ***,the STI(Systems Technologies Inc.)tire model,which can effectively reflect the nonlinear coupling relationship between the tire longitudinal force and lateral force,is established based on experimental data and firstly adopted in the bus YSC system *** this basis,a more accurate bus lateral dynamics model is built and a novel YSC strategy based on ANFTSM,which has the merits of fast transient response,finite time convergence and high robustness against uncertainties and external disturbances,is ***,to solve the optimal allocation problem of the tire forces,whose objective is to achieve the desired direct yaw moment through the effective distribution of the brake force of each tire,the robust least-squares allocation method is *** verify the feasibility,effectiveness and practicality of the proposed bus YSC approach,the TruckSim-Simulink co-simulation results are finally *** co-simulation results show that the lateral stability of bus under special driving conditions has been significantly *** research proposes a more effective design method for bus YSC system based on a more accurate tire model.

关键词： Bus Yaw stability control Sliding mode control STI tire model Co-simulation

Dynamically reconfigurable radio-over-fiber network with medium access control protocol to provide network access to train passengers

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Science China(Information Sciences) 2013年第10期56卷 134-143页

作者： SHEN Xi XU Kun sun xiaoqiang WU Jian LIN JinTong State Key Laboratory of Information Photonics and Optical Communications Beijing University of Posts and Telecommunications

An innovative dynamically reconfgurable radio-over-fber(RoF)network equipped with an intelligent medium access control(MAC)protocol is proposed to provide broadband access to train passengers in railway high-speed mobile *** proposed RoF network architecture is based on a reconfgurable control station and remote access unit(RAU)that is equipped with a fxed flter and tunable *** proposed hybrid frequency-division multiplexing/time division multiple access(FDM/TDMA)based MAC protocol realizes failure detection/recovery and dynamic wavelength allocation to remote access *** result shows that with the proposed MAC protocol,the control station can detect failures and recover and dynamic wavelength allocation can increase the wavelength resource utilization to maintain network performance.

关键词： radio over fber medium access control protocol wavelength allocation failure detection failure recovery

LLTH‑YOLOv5:A Real‑Time Traffic Sign Detection Algorithm for Low‑Light Scenes

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Automotive Innovation 2024年第1期7卷 121-137页

作者： xiaoqiang sun Kuankuan Liu Long Chen Yingfeng Cai Hai Wang Automotive Engineering Research Institute Jiangsu UniversityZhenjiang 212013China School of Automotive and Traffic Engineering Jiangsu UniversityZhenjiang 212013China

Traffic sign detection is a crucial task for autonomous driving ***,the performance of deep learning-based algorithms for traffic sign detection is highly affected by the illumination conditions of *** existing algo-rithms demonstrate high accuracy in well-lit environments,they suffer from low accuracy in low-light *** paper proposes an end-to-end framework,LLTH-YOLOv5,specifically tailored for traffic sign detection in low-light scenarios,which enhances the input images to improve the detection *** proposed framework comproses two stages:the low-light enhancement stage and the object detection *** the low-light enhancement stage,a lightweight low-light enhancement network is designed,which uses multiple non-reference loss functions for parameter learning,and enhances the image by pixel-level adjustment of the input image with high-order *** the object detection stage,BIFPN is introduced to replace the PANet of YOLOv5,while designing a transformer-based detection head to improve the accuracy of small target ***,GhostDarkNet53 is utilized based on Ghost module to replace the backbone network of YOLOv5,thereby improving the real-time performance of the *** experimental results show that the proposed method significantly improves the accuracy of traffic sign detection in low-light scenarios,while satisfying the real-time requirements of autonomous driving.

关键词： Deep learning Traffic sign detection Low-light enhancement YOLOv5 Object detection

Multiscale mathematical models for biological systems

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Frontiers of Mathematics in China 2023年第2期18卷 75-94页

作者： xiaoqiang sun Jiguang BAO School of Mathematics Sun Yat-sen UniversityGuangzhou 510275China School of Mathematical Sciences Beijing Normal UniversityBeijing 100875China Laboratory of Mathematics and Complex Systems Ministry of EducationBeijing 100875China

Life activities are extremely complex phenomena in *** molecular signaling regulation to multi-cellular tissue formation and so on,the biological system consists of multiple temporal,spatial and functional *** mathematical models have extensive applications in life science research due to their capacity of appropriately simulating the complex multiscale biological *** mathematical methods,including deterministic methods,stochastic methods as well as discrete or rule-based methods,have been widely used for modeling biological ***,the models at single scale are not sufficient to simulate complex biological ***,in this paper we give a survey of two multiscale modeling approaches for biological *** approach is continuous stochastic method that couples ordinary differential equations and stochastic differential equations;Another approach is hybrid continuous-discrete method that couples agent-based model with partial differential *** then introduce the applications of these multiscale modeling approaches in systems biology and look ahead to the future research.

关键词： Multi-scale model partial differential equations agent-based model systems biology

NFSI-catalyzed S–S bond exchange reaction for the synthesis of unsymmetrical disulfides

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Chinese Chemical Letters 2022年第9期33卷 4269-4272页

作者： Mengjie Song Qingyue Hu Zheng-Yi Li xiaoqiang sun Ke Yang Jiangsu Key Laboratory of Advanced Catalytic Materials&Technology School of Petrochemical EngineeringChangzhou UniversityChangzhou 213164China Institute of Urban&Rural Mining Changzhou UniversityChangzhou 213164China

The metal-free S–S bond exchange reaction of symmetrical disulfides catalyzed by NFSI is described. This novel protocol provides a facile and efficient approach to accessing important unsymmetrical ***, this strategy could also be utilized in the late-stage functionalization of amino acids, drugs,and natural products. The broad substrate scope, good functional group tolerance and easy accessibility of catalyst indicate that this strategy affords a green and practical complementary method to various unsymmetrical disulfides.

关键词： Metal-free Ssingle bond S bond exchange NFSI Unsymmetrical disulfides Organic synthesis

Novel supramolecular organocatalysts of hydroxyprolinamide based on calix[4]arene scaffold for the enantioselective Biginelli reaction

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Science China Chemistry 2011年第11期54卷 1726-1734页

作者： LI ZhengYi XING HuaiJie HUANG GuoLi sun xiaoqiang JIANG JuLi WANG LeYong Key Laboratory of Fine Petrochemical Engineering School of Petrochemical Engineering Changzhou University Changzhou 213164 China Institute of Chemical Biology and Drug Innovation School of Chemistry and Chemical Engineering Nanjing University Nanjing 210093 China

A series of novel supramolecular organocatalysts of hydroxyprolinamide based on the upper rim of calix[4]arene scaffold have been developed to catalyze enantioselective multi-component Biginelli reaction. Under the optimal conditions, the reactions occurred with moderate-to-excellent enantioselectivities (up to 98% ee). A plausible transition state constructed by the supra- molecular interaction of hydrogen bond and cation-π between catalysts and substrates has been proposed.

关键词： supramolecular organocatalyst calixarene hydroxyprolinamide enantioselective Biginelli reaction

Metal-free direct C(sp^(3))-H functionalization of 2-alkylthiobenzoic acid to access 1,3-benzooxathiin-4-one

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Chinese Chemical Letters 2021年第1期32卷 146-149页

作者： Ke Yang Yi Li Mengjie Song Shengfei Dai Zheng-Yi Li xiaoqiang sun Jiangsu Key Laboratory of Advanced Catalytic Materials&Technology School of Petrochemical EngineeringChangzhou UniversityChangzhou 213164China

Metal-free direct α-C(sp^(3))-H intramolecular cyclization of 2-alkylthiobenzoic acid in the presence of Selectfluor is *** novel strategy provides a facile and efficient method to access important 1,3-benzooxathiin-... 详细信息

关键词： Metal-free C(sp^(3))-H functionalization Selectfluor 1,3-Benzooxathiin-4-one Organic synthesis

Supramolecular interaction controlled and calix[4]arene ligand assisted Pd-catalyzed C(sp3)-H arylation of aliphatic aldehydes

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Chinese Chemical Letters 2022年第12期33卷 5116-5119页

作者： Yao Wu Zhiyan Ma Jing Shi xiaoqiang sun Ke Yang Zheng-Yi Li Jiangsu Key Laboratory of Advanced Catalytic Materials and Technology School of Petrochemical EngineeringChangzhou UniversityChangzhou 213164China

A calix[4]arene ligand assisted directβ-C-H arylation of tertiary aliphatic aldehydes has been developed via a Pd-catalyzed C(sp3)-H functionalization *** strategy exhibited good functional group compatibility and C-H bond *** studies have shown that both synergistic effect and cationic-πsupramolecular interaction between calixarene cavity and transition-metal catalytic center may play an important role in this catalytic *** complementary method would be used in organic and medical chemistry due to the importance of tertiary aliphatic aldehydes.

关键词： Supramolecular interaction Palladium-catalyzed C-H activation Calixarene Aliphatic aldehyde