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Height and attitude active disturbance rejection controller design of a small-scale helicopter

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Science China(Information Sciences) 2015年第3期58卷 142-158页

作者： TANG Shuai YANG QiuHui QIAN ShaoKe zheng zhiqiang College of Mechatronic Engineering and Automation National University of Defense Technology

Small-scale helicopters are very attractive because of their unique ***,autonomous flight control for small-scale helicopters is still a challenging work because they are naturally unstable,strongly nonlinear,and sensitive to *** this paper,we focus on the design of a height and attitude active disturbance rejection controller(ADRC)for a small-scale helicopter constructed in our ***,a comprehensive nonlinear model for the platform is presented,which is obtained through first principles modeling and system *** controller is designed using backstepping technique incorporated with extended state observer(ESO),which is used to estimate the unknown ***,the estimate is introduced into the control law to compensate for the *** design specifications of military rotorcraft are introduced to guide the controller design to achieve specified control *** the physical limitations,reference models are designed to shape the desired control *** last,several flight simulations are carried out to validate the effectiveness and robustness of the proposed *** results show that the proposed controller works well and Level 1 performance can be achieved.

关键词： small-scale helicopter active disturbance rejection control(ADRC) extended state observer(ESO) backstepping disturbance compensation

Second-order sliding mode attitude controller design of a small-scale helicopter

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Science China(Information Sciences) 2016年第11期59卷 128-141页

作者： Shuai TANG Li ZHANG Shaoke QIAN zhiqiang zheng Department of Machinery & Electrical Engineering Logistical Engineering University College of Mechatronic Engineering and Automation National University of Defense Technology

In this paper, the attitude control of a small-scale helicopter is investigated. The main rotor flapping dynamics is explicitly explored to improve the control performance. A two-layer control architecture is adopted:the inner loop controller is designed combining second-order sliding mode control with extended state observer to control the angular rates and yield good robustness properties with respect to model uncertainties; the outer loop controller is used to control the attitude. Experimental results show that the proposed controller yields excellent performance and robustness.

关键词： small-scale helicopter second-order sliding mode extended state observer disturbances robustness

Loading Nickel Atoms on GDY for Efficient CO_(2) Fixation and Conversion

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Chemical Research in Chinese Universities 2022年第1期38卷 92-98页

作者： zheng zhiqiang HE Feng XUE Yurui LI Yuliang Science Center for Material Creation and Energy Conversion School of Chemistry and Chemical EngineeringInstitute of Frontier and Interdisciplinary ScienceShandong UniversityJinan 250100P.R.China Institute of Chemistry Chinese Academy of SciencesBeijing 100190P.R.China University of Chinese Academy of Sciences Beijing 100049P.R.China

Carbon dioxide(CO_(2))is an important and valuable C1 resource for the synthesis of numerous of value-added products. However, efficient fixation and conversion of CO_(2) into organic carbonates under mild conditions remain great challenges. Herein, graphdiyne(GDY)-based nickel atomic catalysts(Ni0/GDYs) were synthesized through a facile in-situ reduction method. Experimental results showed that the obtained Ni0/GDY had outstanding catalytic performances for converting CO_(2) into cyclic carbonates with a high reaction conversion(99%) and reaction selectivity(ca. 100%) at 80℃ and under 1 atm(1 atm=101325 Pa). Specially, the activation energy (Ea) value for the Ni0/GDY is 37.05 kJ/mol, lower than those of reported catalysts. The reaction mechanism was next carefully analyzed by using density functional theory(DFT) calculations. Such an excellent catalytic property could be mainly attributed to the high dispersion of active sites on the Ni0/GDY, and the unique incomplete charge transfer properties of GDY-based zero-valent metallic catalysts.

关键词： Graphdiyne Atomic catalyst Atomic catalysis CO_(2)fixation CO_(2)conversion

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四足机器人稳定高效行进的多步态运动策略

系统仿真学报 2025年第1期37卷 13-24页

作者：张道勋陈谢沅澧钟铮语徐明郑志强卢惠民国防科技大学智能科学学院湖南长沙410073

受四足动物自然步态转换机制的启发,针对运动能效与运动稳定之间的权衡问题,提出了一种多步态行进的运动策略,用以实现四足机器人在多地形场景下的稳定高效运动。根据占空比和相位偏移等参数定义步态,形成切换基础;通过设计有限状态机... 详细信息

受四足动物自然步态转换机制的启发,针对运动能效与运动稳定之间的权衡问题,提出了一种多步态行进的运动策略,用以实现四足机器人在多地形场景下的稳定高效运动。根据占空比和相位偏移等参数定义步态,形成切换基础;通过设计有限状态机并引入参数的仿射变换来建立切换机制,实现了不同步态间的及时切换;基于运输成本CoT(cost of transport)和稳定性指标设计了速度-步态映射表,实现了运动步态的合理选择;结合步态选择策略与步态切换机制实现了变化地形上的步态实时选择与切换。仿真结果与实物实验均表明,所提出的多步态策略能够实现不同地形下四足机器人的高效稳定运动。

关键词：四足机器人运动策略运输成本步态切换步态选择

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Fault-tolerant cooperative control for multiple UAVs based on sliding mode techniques

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Science China(Information Sciences) 2017年第7期60卷 54-66页

作者： Peng LI Xiang YU Xiaoyan PENG zhiqiang zheng Youmin ZHANG College of Mechatronics Engineering and Automation National University of Defense Technology Department of Mechanical and Industrial Engineering Concordia University State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body Hunan University

This paper proposes a fault-tolerant cooperative control(FTCC) design approach for multiple unmanned aerial vehicles(UAVs), where the outer-loop control and the inner-loop fault accommodation are explicitly considered. The reference signals for the inner-loop of the follower UAV can be directly produced by resorting to a proportional control. In the presence of actuator faults, the estimation of the fault information can be completed within finite time. Moreover, the control of the inner-loop is reconfigured based on the fault information adaptation and sliding mode techniques, such that the deleterious effects due to failed actuators can be compensated within finite time. Simulations of UAV cooperative flight are conducted to illustrate the effectiveness of this FTCC scheme.

关键词： fault-tolerant cooperative control unmanned aerial vehicle actuator faults finite-time fault ac commodation

Introduction to Big Data Analytics and the Special Issue on Big Data Methods and Applications

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Journal of Management Analytics 2015年第4期2卷 281-284页

作者： zhiqiang(Eric)zheng Jindal School of Management University of Texas at DallasRichardsonTexasUSA

It is not too much of a stretch to recognize that today’s businessworld is experiencing a fundamental shift towards digitization(Fichman,Dos-Santos,&zheng,2014).The Accenture report(2014)claimed the year 2014 to earmark that‘every business is digital’.Enterprises are embracing digital technologies in the way they do businesses to create new products and services,and new *** this wave of digital innovation,the traditional industry boundaries are being *** example,consumer product companies are becoming Internet companies,industrial companies are becoming customer service companies,and media and entertainment companies are becoming logistics companies.

关键词： companies becoming customer

Distributed Cooperative Current-Sharing Control of Coupled Parallel Charging Systems with Super-Capacitor Loads 36

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Distributed Cooperative Current-Sharing Control of Coupled P...

Rationally designed hollow carbon nanospheres decorated with S,P co-doped NiSe_(2) nanoparticles for high-performance potassium-ion and lithium-ion batteries

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作者： Jiangang Liu zhiqiang zheng School of Mathematics and Statistics Hunan University of Commerce School of Mechatronics Engineering and Automation National University of Defense Technology

ISBN: (纸本)9781538629185

In order to address the output current imbalanced problem of parallel chargers for energy storage type lignt rail vehicles,a distributed cooperative current-sharing scheme is proposed in this *** each charger as an agent,the current-sharing control design can be modeled as the output current consensus-tracking problem of nonlinear and non-identical multi-agent systems with the bounded control *** communication topology between each parallel charger is modeled a directed graph,which only needs a spanning *** order to guarantee the boundedness of the control input,a general saturation function is introduced into the control *** distributed cooperative PID current-sharing controller is designed based on the nearest neighborhood *** system stability and dynamic performance of the proposed cooperative control scheme is evaluated by analyzing the transfer function matrix from the input duty ratio to the output *** the physical parameters and communication topology of the parallel chargers are given in advance,the system stability can be maintained by choosing the proportional,integral and derivative control *** output current of parallel chargers can be balanced by adopting the proposed approach,which is verified by simulating a parallel charging test system.

关键词： Current-Sharing Control Parallel Chargers Multi-Agent Systems Cooperative PID Control

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Journal of Energy Chemistry 2023年第3期78卷 401-411,I0011页

作者： Jiajia Ye Zizhong Chen zhiqiang zheng Zhanghua Fu Guanghao Gong Guang Xia Cheng Hu Shenzhen Research Institute of Shandong University Shenzhen 518057GuangdongChina Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials(Ministry of Education) School of Materials Science and EngineeringShandong UniversityJinan 250061ShandongChina Key Laboratory of Colloid and Interface Chemistry Ministry of EducationSchool of Chemistry and Chemical EngineeringState Key Laboratory of Crystal MaterialShandong UniversityJinan 250100ShandongChina i-Lab Suzhou Institute of Nano-Tech and Nano-Bionics(SINANO)Chinese Academy of SciencesSuzhou 215123JiangsuChina

Hollow nanostructures with external shells and inner voids have been proved to greatly shorten the transport distance of ions/electrons and buffer volume change,especially for the large-sized potassium-ions in secondary *** this work,hollow carbon(HC) nanospheres embedded with S,P co-doped NiSe_(2)nanoparticles are fabricated by "drop and dry" and "dissolving and precipitation" processes to form Ni(OH)2nanocrystals followed by annealing with S and P dopants to form *** resultant S,P-NiSe_(2)/HC composite exhibits excellent cyclic performance with 131.6 mA h g^(-1)at1000 mA g^(-1)after 3000 cycles for K^(+)storage and a capacity of 417.1 mA h g^(-1)at 1000 mA g^(-1)after1000 cycles for Li^(+)storage.K-ion full cells are assembled and deliver superior cycling stability with a ca pacity of 72.5 mA h g^(-1)at 200 mA g^(-1)after 500 *** hollow carbon shell with excellent electrical conductivity effectively promotes the transporta tion and tolerates large volume variation for both K^(+)and Li^(+).Density functional theory calculations confirm that the S and P co-doping NiSe_(2) enables stronger adsorption of K^(+)ions and higher electrical conductivity that contributes to the improved electrochemical performance.

关键词： S,P co-doping NiSe_(2)nanoparticles Hollow carbon nanospheres Potassium-ion batteries Lithium-ion batteries

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Ir0/graphdiyne atomic interface for selective epoxidation

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National Science Review 2023年第8期10卷 173-179页

作者： zhiqiang zheng Lu Qi Yaqi Gao Xiaoyu Luan Yurui Xue Feng He Yuliang Li Shandong Provincial Key Laboratory for Science of Material Creation and Energy Conversion Science Center for Material Creation and Energy Conversion School of Chemistry and Chemical EngineeringShandong University CAS Key Laboratory of Organic Solids Institute of ChemistryChinese Academy of Sciences School of Chemical Sciences University of Chinese Academy of Sciences

The development of catalysts that can selectively and efficiently promote the alkene epoxidation at ambient temperatures and pressures is an important promising path to renewable synthesis of various chemical products. Here we report a new type of zerovalent atom catalysts comprised of zerovalent Ir atoms highly dispersed and anchored on graphdiyne（Ir0/GDY） wherein the Ir0is stabilized by the incomplete charge transfer effect and the confined effect of GDY natural cavity. The Ir0/GDY can selectively and efficiently produce styrene oxides（SO） by electro-oxidizing styrene（ST） in aqueous solutions at ambient temperatures and pressures with high conversion efficiency of ～100%, high SO selectivity of 85.5%, and high Faradaic efficiency（FE） of 55%. Experimental and density functional theory（DFT） calculation results show that the intrinsic activity and stability due to the incomplete charge transfer between Ir0and GDY effectively promoted the electron exchange between the catalyst and reactant molecule, and realized the selective epoxidation of ST to SO. Studies of the reaction mechanism demonstrate that Ir0/GDY proceeds a distinctive pathway for highly selective and active alkene-to-epoxide conversion from the traditional processes. This work presents a new example of constructing zerovalent metal atoms within the GDY matrix toward selective electrocatalytic epoxidation.

关键词： graphdiyne atom catalyst atomic interface selective epoxidation high-performance