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Driving manipulation analysis and control reconfiguration of heavy-haul trains
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作者 LI Zi-yi ZHOU Yan-li +2 位作者 YANG Hui YU Yong-sheng LI Guang-wei 《Journal of Central South University》 2026年第1期506-522,共17页
The safe driving and operation of trains is a necessary condition for ensuring the safe operation of trains.In particular,heavy-haul trains are characterized by the difficulty in driving and operation.Considering the ... The safe driving and operation of trains is a necessary condition for ensuring the safe operation of trains.In particular,heavy-haul trains are characterized by the difficulty in driving and operation.Considering the uncertainties in train driving and operation,this paper analyzes the relationship between the safety of heavy-haul electric locomotive hauled trains and driving and operation.It studies the auxiliary intelligent driving safety operation control methods.Through K-means to identify the characteristics of drivers'driving manipulation,the hidden Markov model adaptively adjusts the train driving and operation sequence,and conducts auxiliary driving reconstruction for heavy-haul locomotive driving and operation.Based on the train running curve and the locomotive traction/braking characteristics,it smoothly controls the exertion of the traction/braking force of heavy-haul locomotives,thereby optimizing the driving safety control of heavy-haul trains in the vehicle-environment-track system.Finally,the train operation simulation and optimized driving verification are carried out by simulating some track sections.The results show that the proposed method can correct and pre-optimize driving operations,improving the smoothness of heavy-haul trains by approximately 10%.It verifies the effectiveness of the proposed train assisted driving control reconstruction method,facilitating the smooth and safe operation of heavy-haul trains. 展开更多
关键词 heavy-haul trains driving manipulation K-means clustering algorithm hidden Markov model control reconfiguration
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Design and implementation of digital closed-loop drive control system of a MEMS gyroscope 被引量:5
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作者 王晓雷 李宏生 杨波 《Journal of Southeast University(English Edition)》 EI CAS 2012年第1期35-40,共6页
In order to effectively control the working state of the gyroscope in drive mode, the drive characteristics of the micro electromechanical system (MEMS) gyroscope are analyzed in principle. A novel drive circuit for... In order to effectively control the working state of the gyroscope in drive mode, the drive characteristics of the micro electromechanical system (MEMS) gyroscope are analyzed in principle. A novel drive circuit for the MEMS gyroscope in digital closed-loop control is proposed, which utilizes a digital phase-locked loop (PLL) in frequency control and an automatic gain control (AGC) method in amplitude control. A digital processing circuit with a field programmable gate array (FPGA) is designed and the experiments are carried out. The results indicate that when the temperature changes, the drive frequency can automatically track the resonant frequency of gyroscope in drive mode and that of the oscillating amplitude holds at a set value. And at room temperature, the relative deviation of the drive frequency is 0.624 ×10^-6 and the oscillating amplitude is 8.0 ×10^-6, which are 0. 094% and 18. 39% of the analog control program, respectively. Therefore, the control solution of the digital PLL in frequency and the AGC in amplitude is feasible. 展开更多
关键词 micro electromechanical system (MEMS) digitalgyroscope drive frequency phase-locked loop (PLL) oscillating amplitude automatic gain control (AGC)
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Model-free Predictive Control of Motor Drives:A Review 被引量:2
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作者 Chenhui Zhou Yongchang Zhang Haitao Yang 《CES Transactions on Electrical Machines and Systems》 2025年第1期76-90,共15页
Model predictive control(MPC)has been deemed as an attractive control method in motor drives by virtue of its simple structure,convenient multi-objective optimization,and satisfactory dynamic performance.However,the s... Model predictive control(MPC)has been deemed as an attractive control method in motor drives by virtue of its simple structure,convenient multi-objective optimization,and satisfactory dynamic performance.However,the strong reliance on mathematical models seriously restrains its practical application.Therefore,improving the robustness of MPC has attained significant attentions in the last two decades,followed by which,model-free predictive control(MFPC)comes into existence.This article aims to reveal the current state of MFPC strategies for motor drives and give the categorization from the perspective of implementation.Based on this review,the principles of the reported MFPC strategies are introduced in detail,as well as the challenges encountered in technology realization.In addition,some of typical and important concepts are experimentally validated via case studies to evaluate the performance and highlight their features.Finally,the future trends of MFPC are discussed based on the current state and reported developments. 展开更多
关键词 Model predictive control Motor drives Parameter robustness Model-free predictive control
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Overview on active disturbance rejection control for electro-mechanical actuation servo drive 被引量:1
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作者 Chunqiang LIU Guangzhao LUO +1 位作者 Zhe CHEN Xiaofeng DING 《Chinese Journal of Aeronautics》 2025年第7期291-309,共19页
Permanent magnet synchronous motor based electro-mechanical actuation servo drives have widespread applications in the aviation field,such as unmanned aerial vehicle electric servos,electric cabin doors,and mechanical... Permanent magnet synchronous motor based electro-mechanical actuation servo drives have widespread applications in the aviation field,such as unmanned aerial vehicle electric servos,electric cabin doors,and mechanical arms.The performance of the servo drive,which encompasses the response to the torque,efficiency,control bandwidth and the steady-state positioning accuracy,significantly influences the performance of the aviation actuation.Consequently,enhancing the control bandwidth and refining the positioning accuracy of aviation electro-mechanical actuation servo drives have emerged as a focal point of research.This paper investigates the multi-source disturbances present in aviation electro-mechanical actuation servo systems and summarizes recent research on high-performance servo control methods based on active disturbance rejection control(ADRC).We present a comprehensive overview of the research status pertaining to servo control architecture,strategies for suppressing disturbances in the current loop,and ADRC-based strategies for the position loop.We delineate the research challenges and difficulties encountered by aviation electro-mechanical actuation servo drive control technology. 展开更多
关键词 Active disturbance rejection control Electric servo drive Permanent magnet synchronous motor Electro-mechanical actuation
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Projective synchronization control and simulation of drive system and response network
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作者 LI De-kui 《兰州大学学报(自然科学版)》 北大核心 2025年第2期208-214,共7页
Projective synchronization problems of a drive system and a particular response network were investigated,where the drive system is an arbitrary system with n+1 dimensions;it may be a linear or nonlinear system,and ev... Projective synchronization problems of a drive system and a particular response network were investigated,where the drive system is an arbitrary system with n+1 dimensions;it may be a linear or nonlinear system,and even a chaotic or hyperchaotic system,the response network is complex system coupled by N nodes,and every node is showed by the approximately linear part of the drive system.Only controlling any one node of the response network by designed controller can achieve the projective synchronization.Some numerical examples were employed to verify the effectiveness and correctness of the designed controller. 展开更多
关键词 pinning control projective synchronization drive system response network
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Fishing Ship Trajectory Tracking Control Based on the Closed-Loop Gain Shaping Algorithm Under Rough Sea
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作者 SONG Chun-yu GUO Te-er SUI Jiang-hua 《China Ocean Engineering》 2025年第2期365-372,共8页
This paper proposes a separated trajectory tracking controller for fishing ships at sea state level 6 to solve the trajectory tracking problem of a fishing ship in a 6-level sea state,and to adapt to different working... This paper proposes a separated trajectory tracking controller for fishing ships at sea state level 6 to solve the trajectory tracking problem of a fishing ship in a 6-level sea state,and to adapt to different working environments and safety requirements.The nonlinear feedback method is used to improve the closed-loop gain shaping algorithm.By introducing the sine function,the problem of excessive control energy of the system can be effectively solved.Moreover,an integral separation design is used to solve the influence of the integral term in conventional PID controllers on the transient performance of the system.In this paper,a common 32.98 m large fiberglass reinforced plastic(FRP)trawler is adopted for simulation research at the winds scale of Beaufort No.7.The results show that the track error is smaller than 3.5 m.The method is safe,feasible,concise and effective and has popularization value in the direction of fishing ship trajectory tracking control.This method can be used to improve the level of informatization and intelligence of fishing ships. 展开更多
关键词 trajectory tracking control nonlinear feedback control fishing ship closed-loop gain shaping algorithm rough sea
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Design and Implementation of Closed-Loop Control of Vector Force in Static Push-the-bit Rotary Steering System
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作者 Liang Yao Kang Hong-bo +4 位作者 Liu Yue Chen wen Sun Yan Ma Li Zhao Yan-Wei 《Applied Geophysics》 2025年第3期796-803,896,共9页
Rotary steering systems(RSSs)have been increasingly used to develop horizontal wells.A static push-the-bit RSS uses three hydraulic modules with varying degrees of expansion and contraction to achieve changes in the p... Rotary steering systems(RSSs)have been increasingly used to develop horizontal wells.A static push-the-bit RSS uses three hydraulic modules with varying degrees of expansion and contraction to achieve changes in the pushing force acting on the wellbore in different sizes and directions within a circular range,ultimately allowing the wellbore trajectory to be drilled in a predetermined direction.By analyzing its mathematical principles and the actual characteristics of the instrument,a vector force closed-loop control method,including steering and holding modes,was designed.The adjustment criteria for the three hydraulic modules are determined to achieve rapid adjustment of the vector force.The theoretical feasibility of the developed method was verified by comparing its results with the on-site application data of an imported rotary guidance system. 展开更多
关键词 Static push-the-bit hydraulic modules closed-loop control vector force working mode
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Optimized PID neural network closed-loop control for basal ganglia network in Parkinson's disease
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作者 Hengxi Zhang Honghui Zhang +1 位作者 Shuang Liu Lin Du 《Chinese Physics B》 2025年第12期193-206,共14页
Conventional open-loop deep brain stimulation(DBS)systems with fixed parameters fail to accommodate interindividual pathological differences in Parkinson's disease(PD)management while potentially inducing adverse ... Conventional open-loop deep brain stimulation(DBS)systems with fixed parameters fail to accommodate interindividual pathological differences in Parkinson's disease(PD)management while potentially inducing adverse effects and causing excessive energy consumption.In this paper,we present an adaptive closed-loop framework integrating a Yogi-optimized proportional–integral–derivative neural network(Yogi-PIDNN)controller.The Yogi-augmented gradient adaptation mechanism accelerates the convergence of general PIDNN controllers in high-dimensional nonlinear control systems while reducing control energy usage.In addition,a system identification method establishes input–output dynamics for pre-training stimulation waveforms,bypassing real-time parameter-tuning constraints and thereby enhancing closed-loop adaptability.Finally,a theoretical analysis based on Lyapunov stability criteria establishes a sufficient condition for closed-loop stability within the identified model.Computational validations demonstrate that our approach restores thalamic relay reliability while reducing energy consumption by(81.0±0.7)%across multi-frequency tests.This study advances adaptive neuromodulation by synergizing data-driven pre-training with stability-guaranteed real-time control,offering a novel framework for energy-efficient and personalized Parkinson's therapy. 展开更多
关键词 Parkinson's disease closed-loop deep brain stimulation PID neural network adaptive control
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A review of artificial intelligence in train driving and control
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作者 Yunxiang Xie Huachang Yang 《Railway Sciences》 2025年第6期762-782,共21页
Purpose–In recent years,the rapid advancement of artificial intelligence(AI)has exerted profound impacts on and provided strong impetus to numerous fields in the industrial sector.Within the railway industry,AI has d... Purpose–In recent years,the rapid advancement of artificial intelligence(AI)has exerted profound impacts on and provided strong impetus to numerous fields in the industrial sector.Within the railway industry,AI has driven continuous upgrading and optimization of intelligent train control technology,thanks to its enhanced computational capabilities derived from advanced algorithms and models,as well as its role in improving safety performance.Integrating AI technology more extensively into train autonomous driving and control has thus become an inevitable trend in the global development of railways.Design/methodology/approach–This paper,therefore,conducts a comprehensive analysis of the development progress and current status of AI technology applications in the field of train driving and control on a global scale.It systematically sorts out and analyzes the advantages of various AI technologies and the positive impacts they bring to the upgrading of train control technology,elucidates the feasibility and future prospects of applying a range of emerging AI technologies from the perspective of technical theory and provides guidance for the intelligent development of this field from a practical perspective.Findings–The application of AI technology in the train driving and control field is still in its infancy.While a large number of AI technologies have been widely adopted,there remains significant room for further optimization and improvement of these technologies.Additionally,a variety of AI technologies that have been applied in other industrial sectors but not yet widely implemented in training autonomous driving and control have demonstrated tremendous development potential.Originality/value–The research findings provide references and guidance for advancing train control technology,promoting the digital transformation of railways,accelerating the overall optimization and upgrading of railway industry technologies,and facilitating the accelerated development of global railways. 展开更多
关键词 Autonomous train driving Artificial intelligence Train control Train safety Quantum computing
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DRG-DCC:A Driving Risk Gaming Based Distributed Congestion Control Method for C-V2X Technology
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作者 Lingqiu Zeng Peibing Sa +4 位作者 Qingwen Han Lei Ye Letian Yang Cheng Zhang Jiqiang Cheng 《Computers, Materials & Continua》 2025年第5期2059-2086,共28页
Congestion control is an inherent challenge of V2X(Vehicle to Everything)technologies.Due to the use of a broadcasting mechanism,channel congestion becomes severe with the increase in vehicle density.The researchers s... Congestion control is an inherent challenge of V2X(Vehicle to Everything)technologies.Due to the use of a broadcasting mechanism,channel congestion becomes severe with the increase in vehicle density.The researchers suggested reducing the frequency of packet dissemination to relieve congestion,which caused a rise in road driving risk.Obviously,high-risk vehicles should be able to send messages timely to alarm surrounding vehicles.Therefore,packet dissemination frequency should be set according to the corresponding vehicle’s risk level,which is hard to evaluate.In this paper,a two-stage fuzzy inference model is constructed to evaluate a vehicle’s risk level,while a congestion control algorithm DRG-DCC(Driving Risk Game-Distributed Congestion Control)is proposed.Moreover,HPSO is employed to find optimal solutions.The simulation results show that the proposed method adjusts the transmission frequency based on driving risk,effectively striking a balance between transmission delay and channel busy rate. 展开更多
关键词 Distributed congestion control fuzzy inference driving risk evaluation game theory Nash equilibrium
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New digital drive phase control for improving bias stability of silicon MEMS gyroscope 被引量:3
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作者 夏国明 杨波 王寿荣 《Journal of Southeast University(English Edition)》 EI CAS 2011年第1期47-51,共5页
In order to improve the bias stability of the micro-electro mechanical system(MEMS) gyroscope and reduce the impact on the bias from environmental temperature,a digital signal processing method is described for impr... In order to improve the bias stability of the micro-electro mechanical system(MEMS) gyroscope and reduce the impact on the bias from environmental temperature,a digital signal processing method is described for improving the accuracy of the drive phase in the gyroscope drive mode.Through the principle of bias signal generation,it can be concluded that the deviation of the drive phase is the main factor affecting the bias stability.To fulfill the purpose of precise drive phase control,a digital signal processing circuit based on the field-programmable gate array(FPGA) with the phase-lock closed-loop control method is described and a demodulation method for phase error suppression is given.Compared with the analog circuit,the bias drift is largely reduced in the new digital circuit and the bias stability is improved from 60 to 19 °/h.The new digital control method can greatly increase the drive phase accuracy,and thus improve the bias stability. 展开更多
关键词 silicon micro-electro mechanical system(MEMS) gyroscope bias drift drive phase control field-programmable gate array(FPGA)
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Model predictive control for hybrid vehicle ecological driving using traffic signal and road slope information 被引量:11
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作者 Kaijiang YU Junqi YANG Daisuke YAMAGUCHI 《Control Theory and Technology》 EI CSCD 2015年第1期17-28,共12页
This paper presents development of a control system for ecological driving of a hybrid vehicle. Prediction using traffic signal and road slope information is considered to improve the fuel economy. It is assumed that ... This paper presents development of a control system for ecological driving of a hybrid vehicle. Prediction using traffic signal and road slope information is considered to improve the fuel economy. It is assumed that the automobile receives traffic signal information from intelligent transportation systems (ITS). Model predictive control is used to calculate optimal vehicle control inputs using traffic signal and road slope information. The performance of the proposed method was analyzed through computer simulation results. Both the fuel economy and the driving profile are optimized using the proposed approach. It was observed that fuel economy was improved compared with driving of a typical human driving model. 展开更多
关键词 Ecological driving model predictive control intelligent transportation systems traffic signal optimal control
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Surrounding rock control of gob-side entry driving with narrow coal pillar and roadway side sealing technology in Yangliu Coal Mine 被引量:7
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作者 Zha Wenhua Shi Hao +1 位作者 Liu San Kang Changhao 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2017年第5期819-823,共5页
Gob-side entry driving can increase coal recovery ratio, and it is implied in many coal mines. Based on geological condition of 10416 working face tailentry in Yangliu Coal Mine, the surrounding rock deformation chara... Gob-side entry driving can increase coal recovery ratio, and it is implied in many coal mines. Based on geological condition of 10416 working face tailentry in Yangliu Coal Mine, the surrounding rock deformation characteristics of gob-side entry driving with narrow coal pillar is analysed, reasonable size of coal pillar and reasonable roadway excavation time after mining are achieved. Surrounding rock control technology and effective roadway side sealing technology are proposed and are taken into field practice. The results showed that a safer and more efficient mining of working face can be achieved. In addition, results of this paper also have important theoretical significance and valuable reference for surrounding rock control technology of gob-side entry driving with narrow coal pillar under special geological condition. 展开更多
关键词 Narrow coal PILLAR Gob-side ENTRY driving SURROUNDING rock control ROADWAY SIDE sealing technology
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Direct Yaw Moment Control for Distributed Drive Electric Vehicle Handling Performance Improvement 被引量:33
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作者 YU Zhuoping LENG Bo +2 位作者 XIONG Lu FENG Yuan SHI Fenmiao 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2016年第3期486-497,共12页
For a distributed drive electric vehicle(DDEV)driven by four in-wheel motors,advanced vehicle dynamic control methods can be realized easily because motors can be controlled independently,quickly and precisely.And dir... For a distributed drive electric vehicle(DDEV)driven by four in-wheel motors,advanced vehicle dynamic control methods can be realized easily because motors can be controlled independently,quickly and precisely.And direct yaw-moment control(DYC)has been widely studied and applied to vehicle stability control.Good vehicle handling performance:quick yaw rate transient response,small overshoot,high steady yaw rate gain,etc,is required by drivers under normal conditions,which is less concerned,however.Based on the hierarchical control methodology,a novel control system using direct yaw moment control for improving handling performance of a distributed drive electric vehicle especially under normal driving conditions has been proposed.The upper-loop control system consists of two parts:a state feedback controller,which aims to realize the ideal transient response of yaw rate,with a vehicle sideslip angle observer;and a steering wheel angle feedforward controller designed to achieve a desired yaw rate steady gain.Under the restriction of the effect of poles and zeros in the closed-loop transfer function on the system response and the capacity of in-wheel motors,the integrated time and absolute error(ITAE)function is utilized as the cost function in the optimal control to calculate the ideal eigen frequency and damper coefficient of the system and obtain optimal feedback matrix and feedforward matrix.Simulations and experiments with a DDEV under multiple maneuvers are carried out and show the effectiveness of the proposed method:yaw rate rising time is reduced,steady yaw rate gain is increased,vehicle steering characteristic is close to neutral steer and drivers burdens are also reduced.The control system improves vehicle handling performance under normal conditions in both transient and steady response.State feedback control instead of model following control is introduced in the control system so that the sense of control intervention to drivers is relieved. 展开更多
关键词 direct yaw moment control distributed drive electric vehicle handling performance improvement state feedback control
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Study on the Driving Style Adaptive Vehicle Longitudinal Control Strategy 被引量:11
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作者 Jing Huang Yimin Chen +2 位作者 Xiaoyan Peng Lin Hu Dongpu Cao 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2020年第4期1107-1115,共9页
This paper presents a fusion control strategy of adaptive cruise control(ACC) and collision avoidance(CA),which takes into account a driver’s behavioral style. First, a questionnaire survey was performed to identify ... This paper presents a fusion control strategy of adaptive cruise control(ACC) and collision avoidance(CA),which takes into account a driver’s behavioral style. First, a questionnaire survey was performed to identify driver type, and the corresponding driving behavioral data were collected via driving simulator experiments, which served as the template data for the online identification of driver type. Then, the driveradaptive ACC/CA fusion control strategy was designed, and its effect was verified by virtual experiments. The results indicate that the proposed control strategy could achieve the fusion control of ACC and CA successfully and improve driver adaptability and comfort. 展开更多
关键词 Adaptive cruise control collision avoidance driving simulator experiment driving style fusion control
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Dynamics and adaptive control of a dual-arm space robot with closed-loop constraints and uncertain inertial parameters 被引量:22
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作者 Ying-Hong Jia Quan Hu Shi-Jie Xu 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2014年第1期112-124,共13页
A dynamics-based adaptive control approach is proposed for a planar dual-arm space robot in the presence of closed-loop constraints and uncertain inertial parameters of the payload. The controller is capable of contro... A dynamics-based adaptive control approach is proposed for a planar dual-arm space robot in the presence of closed-loop constraints and uncertain inertial parameters of the payload. The controller is capable of controlling the po- sition and attitude of both the satellite base and the payload grasped by the manipulator end effectors. The equations of motion in reduced-order form for the constrained system are derived by incorporating the constraint equations in terms of accelerations into Kane's equations of the unconstrained system. Model analysis shows that the resulting equations perfectly meet the requirement of adaptive controller design. Consequently, by using an indirect approach, an adaptive control scheme is proposed to accomplish position/attitude trajectory tracking control with the uncertain parameters be- ing estimated on-line. The actuator redundancy due to the closed-loop constraints is utilized to minimize a weighted norm of the joint torques. Global asymptotic stability is proven by using Lyapunov's method, and simulation results are also presented to demonstrate the effectiveness of the proposed approach. 展开更多
关键词 Space robot Dynamics. Adaptive control closed-loop constraint Parameter uncertainty - Kane's equation
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Four Wheel Independent Drive Electric Vehicle Lateral Stability Control Strategy 被引量:15
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作者 Yantao Tian Xuanhao Cao +1 位作者 Xiaoyu Wang Yanbo Zhao 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2020年第6期1542-1554,共13页
In this paper,a kind of lateral stability control strategy is put forward about the four wheel independent drive electric vehicle.The design of control system adopts hierarchical structure.Unlike the previous control ... In this paper,a kind of lateral stability control strategy is put forward about the four wheel independent drive electric vehicle.The design of control system adopts hierarchical structure.Unlike the previous control strategy,this paper introduces a method which is the combination of sliding mode control and optimal allocation algorithm.According to the driver’s operation commands(steering angle and speed),the steady state responses of the sideslip angle and yaw rate are obtained.Based on this,the reference model is built.Upper controller adopts the sliding mode control principle to obtain the desired yawing moment demand.Lower controller is designed to satisfy the desired yawing moment demand by optimal allocation of the tire longitudinal forces.Firstly,the optimization goal is built to minimize the actuator cost.Secondly,the weighted least-square method is used to design the tire longitudinal forces optimization distribution strategy under the constraint conditions of actuator and the friction oval.Beyond that,when the optimal allocation algorithm is not applied,a method of axial load ratio distribution is adopted.Finally,Car Sim associated with Simulink simulation experiments are designed under the conditions of different velocities and different pavements.The simulation results show that the control strategy designed in this paper has a good following effect comparing with the reference model and the sideslip angle is controlled within a small rang at the same time.Beyond that,based on the optimal distribution mode,the electromagnetic torque phase of each wheel can follow the trend of the vertical force of the tire,which shows the effectiveness of the optimal distribution algorithm. 展开更多
关键词 Four wheel drive electric vehicle least square method moment distribution sliding mode controller stability control
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Connect & Drive:design and evaluation of cooperative adaptive cruise control for congestion reduction 被引量:10
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作者 Jeroen PLOEG Alex F.A.SERRARENS Geert J.HEIJENK 《Journal of Modern Transportation》 2011年第3期207-213,共7页
Road throughput can be increased by driving at small inter-vehicle time gaps. The amplification of velocity disturbances in upstream direction, however, poses limitations to the minimum feasible time gap. This effect ... Road throughput can be increased by driving at small inter-vehicle time gaps. The amplification of velocity disturbances in upstream direction, however, poses limitations to the minimum feasible time gap. This effect is covered by the notion of string stability. String-stable behavior is thus considered an essential requirement for the design of automatic distance control systems, which are needed to allow for safe driving at time gaps well below 1 s. Using wireless inter-vehicle communications to provide real-time information of the preceding vehicle, in addition to the information obtained by common Adaptive Cruise Control (ACC) sensors, appears to significantly decrease the feasible time gap, which is shown by practical experiments with a test fleet consisting of six passenger vehicles. The large-scale deployment of this system, known as Cooperative ACC (CACC), however, poses challenges with respect to the reliability of the wireless communication system. A solution for this scalability problem can be found in decreasing the transmission power and/or beaconing rate, or adapting the communications protocol. Although the main CACC objective is to increase road throughput, the first commercial application of CACC is foreseen to be in truck platooning, since short distance following is expected to yield significant fuel savings in this case. 展开更多
关键词 cooperative adaptive cruise control (CACC) string stability cooperative driving traffic congestion fuel efficiency
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Variants of Secondary Control with Power Recovery for Loading Hydraulic Driving Device 被引量:4
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作者 LI Wanguo FU Yongling +1 位作者 CHEN Juan QI Xiaoye 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2015年第3期618-633,共16页
Current high power load simulators are generally incapable of obtaining both high loading performance and high energy efficiency. Simulators with high energy efficiency are used to simulate static-state load, and thos... Current high power load simulators are generally incapable of obtaining both high loading performance and high energy efficiency. Simulators with high energy efficiency are used to simulate static-state load, and those with high dynamic performance typically have low energy efficiency. In this paper, the variants of secondary control(VSC) with power recovery are developed to solve this problem for loading hydraulic driving devices that operate under variable pressure, unlike classical secondary control(CSC) that operates in constant pressure network. Hydrostatic secondary control units are used as the loading components, by which the absorbed mechanical power from the tested device is converted into hydraulic power and then fed back into the tested system through 4 types of feedback passages(FPs). The loading subsystem can operate in constant pressure network, controlled variable pressure network, or the same variable pressure network as that of the tested device by using different FPs. The 4 types of systems are defined, and their key techniques are analyzed, including work principle, simulating the work state of original tested device, static operation points, loading performance, energy efficiency, and control strategy, etc. The important technical merits of the 4 schemes are compared, and 3 of the schemes are selected, designed, simulated using AMESim and evaluated. The researching results show that the investigated systems can simulate the given loads effectively, realize the work conditions of the tested device, and furthermore attain a high power recovery efficiency that ranges from 0.54 to 0.85, even though the 3 schemes have different loading performances and energy efficiencies. This paper proposes several loading schemes that can achieve both high dynamic performance and high power recovery efficiency. 展开更多
关键词 load simulator variants of secondary control power recovery efficiency energy regeneration hydraulic driving device SIMULATION A
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Force Control Compensation Method with Variable Load Stiffness and Damping of the Hydraulic Drive Unit Force Control System 被引量:10
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作者 KONG Xiangdong BA Kaixian +3 位作者 YU Bin CAO Yuan ZHU Qixin ZHAO Hualong 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2016年第3期454-464,共11页
Each joint of hydraulic drive quadruped robot is driven by the hydraulic drive unit(HDU),and the contacting between the robot foot end and the ground is complex and variable,which increases the difficulty of force con... Each joint of hydraulic drive quadruped robot is driven by the hydraulic drive unit(HDU),and the contacting between the robot foot end and the ground is complex and variable,which increases the difficulty of force control inevitably.In the recent years,although many scholars researched some control methods such as disturbance rejection control,parameter self-adaptive control,impedance control and so on,to improve the force control performance of HDU,the robustness of the force control still needs improving.Therefore,how to simulate the complex and variable load characteristics of the environment structure and how to ensure HDU having excellent force control performance with the complex and variable load characteristics are key issues to be solved in this paper.The force control system mathematic model of HDU is established by the mechanism modeling method,and the theoretical models of a novel force control compensation method and a load characteristics simulation method under different environment structures are derived,considering the dynamic characteristics of the load stiffness and the load damping under different environment structures.Then,simulation effects of the variable load stiffness and load damping under the step and sinusoidal load force are analyzed experimentally on the HDU force control performance test platform,which provides the foundation for the force control compensation experiment research.In addition,the optimized PID control parameters are designed to make the HDU have better force control performance with suitable load stiffness and load damping,under which the force control compensation method is introduced,and the robustness of the force control system with several constant load characteristics and the variable load characteristics respectively are comparatively analyzed by experiment.The research results indicate that if the load characteristics are known,the force control compensation method presented in this paper has positive compensation effects on the load characteristics variation,i.e.,this method decreases the effects of the load characteristics variation on the force control performance and enhances the force control system robustness with the constant PID parameters,thereby,the online PID parameters tuning control method which is complex needs not be adopted.All the above research provides theoretical and experimental foundation for the force control method of the quadruped robot joints with high robustness. 展开更多
关键词 quadruped robot force control system hydraulic drive unit force control compensation method variable load stiffness and damping simulation
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