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Adaptive Robust Servo Control for Vertical Electric Stabilization System of Tank and Experimental Validation
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作者 Darui Lin Xiuye Wang +1 位作者 Yimin Wang Guolai Yang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第1期326-342,共17页
A tracking stability control problem for the vertical electric stabilization system of moving tank based on adaptive robust servo control is addressed.This paper mainly focuses on two types of possibly fast timevaryin... A tracking stability control problem for the vertical electric stabilization system of moving tank based on adaptive robust servo control is addressed.This paper mainly focuses on two types of possibly fast timevarying but bounded uncertainty within the vertical electric stabilization system:model parameter uncertainty and uncertain nonlinearity.First,the vertical electric stabilization system is constructed as an uncertain nonlinear dynamic system that can reflect the practical mechanics transfer process of the system.Second,the dynamical equation in the form of state space is established by designing the angular tracking error.Third,the comprehensive parameter of system uncertainty is designed to estimate the most conservative effects of uncertainty.Finally,an adaptive robust servo control which can effectively handle the combined effects of complex nonlinearity and uncertainty is proposed.The feasibility of the proposed control strategy under the practical physical condition is validated through the tests on the experimental platform.This paper pioneers the introduction of the internal nonlinearity and uncertainty of the vertical electric stabilization system into the settlement of the tracking stability control problem,and validates the advanced servo control strategy through experiment for the first time. 展开更多
关键词 Adaptive robust servo control Experimental validation Nonlinearity compensation system uncertainty Vertical electric stabilization system
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Stochastic sampled-data multi-objective control of active suspension systems for in-wheel motor driven electric vehicles
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作者 Iftikhar Ahmad Xiaohua Ge Qing-Long Han 《Journal of Automation and Intelligence》 2024年第1期2-18,共17页
This paper addresses the sampled-data multi-objective active suspension control problem for an in-wheel motor driven electric vehicle subject to stochastic sampling periods and asynchronous premise variables.The focus... This paper addresses the sampled-data multi-objective active suspension control problem for an in-wheel motor driven electric vehicle subject to stochastic sampling periods and asynchronous premise variables.The focus is placed on the scenario that the dynamical state of the half-vehicle active suspension system is transmitted over an in-vehicle controller area network that only permits the transmission of sampled data packets.For this purpose,a stochastic sampling mechanism is developed such that the sampling periods can randomly switch among different values with certain mathematical probabilities.Then,an asynchronous fuzzy sampled-data controller,featuring distinct premise variables from the active suspension system,is constructed to eliminate the stringent requirement that the sampled-data controller has to share the same grades of membership.Furthermore,novel criteria for both stability analysis and controller design are derived in order to guarantee that the resultant closed-loop active suspension system is stochastically stable with simultaneous𝐻2 and𝐻∞performance requirements.Finally,the effectiveness of the proposed stochastic sampled-data multi-objective control method is verified via several numerical cases studies in both time domain and frequency domain under various road disturbance profiles. 展开更多
关键词 Active suspension system Electric vehicles In-wheel motor Stochastic sampling Dynamic dampers Sampled-data control Multi-objective control
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The General Configuration of CEV1 Electric Vehicle's Electrical System and the Design of Its Control Sequence
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作者 崔淑梅 Qiu Changhua +1 位作者 Ge Xin CHENG Shukang 《High Technology Letters》 EI CAS 2001年第2期83-86,共4页
The configuration an electric vehicle's electrical system and its control sequence design scheme was discussed. Vehicle management unit (VMU), power management unit (PMU) and battery management unit (BMU) were use... The configuration an electric vehicle's electrical system and its control sequence design scheme was discussed. Vehicle management unit (VMU), power management unit (PMU) and battery management unit (BMU) were used as the control units in the vehicle. VMU was used as master control unit, PMU was used as the traction control unit and BMU was used as battery management unit. The concentrated single module control was found to be on one of its configurations. 展开更多
关键词 Electric vehicle electrical system Sequence control
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An Integrated Control Framework for Torque Vectoring and Active Suspension System 被引量:1
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作者 Jiwei Feng Jinhao Liang +6 位作者 Yanbo Lu Weichao Zhuang Dawei Pi Guodong Yin Liwei Xu Pai Peng Chaobin Zhou 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2024年第1期62-73,共12页
Four-wheel independently driven electric vehicles(FWID-EV)endow a flexible and scalable control framework to improve vehicle performance.This paper integrates the torque vectoring and active suspension system(ASS)to e... Four-wheel independently driven electric vehicles(FWID-EV)endow a flexible and scalable control framework to improve vehicle performance.This paper integrates the torque vectoring and active suspension system(ASS)to enhance the vehicle’s longitudinal and vertical motion control performance.While the nonlinear characteristic of the tire model leads to a relatively heavier computational burden.To facilitate the controller design and ease the load,a half-vehicle dynamics system is built and simplified to the linear-time-varying(LTV)model.Then a model predictive controller is developed by formulating the objective function by comprehensively considering the safety,energy-saving and comfort requirements.The in-wheel motor efficiency and the power loss of tire slip are treated as optimization indices in this work to reduce energy consumption.Finally,the effectiveness of the proposed controller is verified through the rapid-control-prototype(RCP)test.The results demonstrate the enhancement of the energy-saving as well as comfort on the basis of vehicle stability. 展开更多
关键词 Four-wheel independently driven electric vehicles Tire nonlinearity Linear-time-varying(LTV)model Model predictive control Rapid control prototype
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Adjusting the Parameters of PI Regulator in All-electrical Tank Gun Control System by Computer Program
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作者 臧克茂 贺跃 +1 位作者 李匡成 李长兵 《Defence Technology(防务技术)》 SCIE EI CAS 2005年第2期140-145,共6页
Both the traverse subsystem and the elevation subsystem of the all-electrical tank gun control system are composed of electrical drive control system respectively. The parameters of PI regulator in these electrical dr... Both the traverse subsystem and the elevation subsystem of the all-electrical tank gun control system are composed of electrical drive control system respectively. The parameters of PI regulator in these electrical drive control systems affect the performance of the control system seriously. Up to now, there is not a simple and practical method for choosing regulator parameters, which are usually determined by repeated and continual readjustment. This method is low efficient, and the parameters got are not always optimal. A method for on-line adjusting the parameters of PI regulator in the electrical drive control system by computer program is introduced in this paper. The function of adjusting PI parameters of the electrical drive control system is realized by PC program written by VC++ and controlling program written by assemble language and by the communication between PC and DSP completed by the control MSCOMM in VC++6.0. The method as mentioned above which is applied for an all-electrical tank gun control system under development is proved very available, a better performance might be obtained for the all-electrical tank gun control system easily. 展开更多
关键词 PI REGULATOR SERIAL communication all-electrical TANK GUN control system
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Electrically controllable spin filtering in zigzag phosphorene nanoribbon based normal–antiferromagnet–normal junctions
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作者 李锐岗 刘军丰 汪军 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第1期666-670,共5页
We investigated the electric controllable spin-filtering effect in a zigzag phosphorene nanoribbon(ZPNR) based normal–antiferromagnet–normal junction. Two ferromagnets are closely coupled to the edges of the nanorib... We investigated the electric controllable spin-filtering effect in a zigzag phosphorene nanoribbon(ZPNR) based normal–antiferromagnet–normal junction. Two ferromagnets are closely coupled to the edges of the nanoribbon and form the edge-to-edge antiferromagnetism. Under an in-plane electric field, the two degenerate edge bands of the edge-to-edge antiferromagnet split into four spin-polarized sub-bands and a 100% spin-polarized current can be easily induced with the maximal conductance 2e~2/h. The spin polarization changes with the strength of the electric field and the exchange field,and changes sign at opposite electric fields. The spin-polarized current switches from one edge to the other by reversing the direction of the electric field. The edge current can also be controlled spatially by changing the electric potential of the scattering region. The manipulation of edge current is useful in spin-transfer-torque magnetic random-access memory and provides a practical way to develop controllable spintronic devices. 展开更多
关键词 zigzag phosphorene electrically controllable spin filter quantum transport
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Safety and effectiveness of electromyography-induced rehabilitation treatment after epidural electrical stimulation for spinal cord injury:study protocol for a prospective,randomized,controlled trial 被引量:4
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作者 Xiao-Pei Sun Jie-Jian Shi +5 位作者 Yong Bao Jie Zhang Hui-Juan Pan Dian-You Li Yu Liang Qing Xie 《Neural Regeneration Research》 SCIE CAS CSCD 2023年第4期819-824,共6页
Epidural electrical stimulation is a new treatment method for spinal cord injury(SCI).Its efficacy and safety have previously been reported.Rehabilitation treatment after epidural electrical stimulation is important t... Epidural electrical stimulation is a new treatment method for spinal cord injury(SCI).Its efficacy and safety have previously been reported.Rehabilitation treatment after epidural electrical stimulation is important to ensure and improve the postoperative efficacy of epidural electrical stimulation in patients with SCI.Considering that electromyography(EMG)-induced rehabilitation treatment can accurately match the muscle contraction of patients with SCI,we designed a study protocol for a prospective,randomized controlled trial.In this trial,on the premise of adjusting the spinal cord electrical stimulator to obtain the maximum EMG signal of the target muscle,patients with SCI receiving epidural electrical stimulation will undergo EMG-induced rehabilitation treatment.Recovery of muscle strength of key muscles,quality of life,safety and therapeutic effects will be monitored.Twenty patients with SCI who are scheduled to undergo epidural electrical stimulation in Shanghai Ruijin Rehabilitation Hospital will be randomly divided into two groups with 10 patients per group.The control group will receive conventional rehabilitation treatment.The EMG-induced rehabilitation group will receive EMG-induced rehabilitation treatment of the target muscles of the upper and lower limbs based on conventional rehabilitation treatment.After rehabilitation treatment,follow up for all patients will occur at 2 weeks and 1,3 and 6 months.The primary outcome measure of this trial will be evaluation of target muscle recovery using the Manual Muscle Testing grading scale.Secondary outcome measures will include modified Barthel Index scores,integrated EMG values,the visual analogue scale,Spinal Cord Independence Measure scores,and modified Ashworth scale scores.The safety indicator will be the incidence of adverse events.This trial will collect data regarding the therapeutic effects of EMG-induced rehabilitation in patients with SCI receiving epidural electrical stimulation for 6 months after rehabilitation treatment.Findings from this trial will help develop rehabilitation methods in patients with SCI after epidural electrical stimulation.This study protocol was approved by Ethics Committee of Shanghai Ruijin Rehabilitation Hospital(Approval No.RKIRB2022-12)on February 15,2022 and was registered with Chinese Clinical Trial Registry(registration number:ChiCTR2200061674;date:June 30,2022).Study protocol version:1.0. 展开更多
关键词 electromyography-induced rehabilitation epidural electrical stimulation muscle strength pain quality of life randomized controlled trial recovery spinal cord injury
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Coordinated Voltage Control of Distribution Network ConsideringMultiple Types of Electric Vehicles
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作者 Liang Liu Guangda Xu +3 位作者 Yuan Zhao Yi Lu Yu Li Jing Gao 《Energy Engineering》 EI 2024年第2期377-404,共28页
The couple between the power network and the transportation network(TN)is deepening gradually with the increasing penetration rate of electric vehicles(EV),which also poses a great challenge to the traditional voltage... The couple between the power network and the transportation network(TN)is deepening gradually with the increasing penetration rate of electric vehicles(EV),which also poses a great challenge to the traditional voltage control scheme.In this paper,we propose a coordinated voltage control strategy for the active distribution networks considering multiple types of EV.In the first stage,the action of on-load tap changer and capacitor banks,etc.,are determined by optimal power flow calculation,and the node electricity price is also determined based on dynamic time-of-use tariff mechanism.In the second stage,multiple operating scenarios of multiple types of EVs such as cabs,private cars and buses are considered,and the scheduling results of each EV are solved by building an optimization model based on constraints such as queuing theory,Floyd-Warshall algorithm and traffic flow information.In the third stage,the output power of photovoltaic and energy storage systems is fine-tuned in the normal control mode.The charging power of EVs is also regulated in the emergency control mode to reduce the voltage deviation,and the amount of regulation is calculated based on the fair voltage control mode of EVs.Finally,we test the modified IEEE 33-bus distribution system coupled with the 24-bus Beijing TN.The simulation results show that the proposed scheme can mitigate voltage violations well. 展开更多
关键词 Electric vehicle transportation network voltage control queuing theory
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Design and Analysis of Power and Transmission System of Downhole Pure Electric Command Vehicle
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作者 Md Jahangir Alam Md Shahriar Sujan +1 位作者 Md. Al Imran Tapu Joy Howlader 《Journal of Transportation Technologies》 2024年第1期31-52,共22页
Electric vehicles use electric motors, which turn electrical energy into mechanical energy. As electric motors are conventionally used in all the industry, it is an established development site. It’s a mature technol... Electric vehicles use electric motors, which turn electrical energy into mechanical energy. As electric motors are conventionally used in all the industry, it is an established development site. It’s a mature technology with ideal power and torque curves for vehicular operation. Conventional vehicles use oil and gas as fuel or energy storage. Although they also have an excellent economic impact, the continuous use of oil and gas threatened the world’s reservation of total oil and gas. Also, they emit carbon dioxide and some toxic ingredients through the vehicle’s tailpipe, which causes the greenhouse effect and seriously impacts the environment. So, as an alternative, electric car refers to a green technology of decarbonization with zero emission of greenhouse gases through the tailpipe. So, they can remove the problem of greenhouse gas emissions and solve the world’s remaining non-renewable energy storage problem. Pure electric vehicles (PEV) can be applied in all spheres, but their special implementation can only be seen in downhole operations. They are used for low noise and less pollution in the downhole process. In this study, the basic structure of the pure electric command vehicle is studied, the main components of the command vehicle power system, namely the selection of the drive motor and the power battery, are analyzed, and the main parameters of the drive motor and the power battery are designed and calculated. The checking calculation results show that the power and transmission system developed in this paper meets the design requirements, and the design scheme is feasible and reasonable. 展开更多
关键词 Pure Electric Vehicles TRANSMISSION GEARS Electronic Differential control Algorithms
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Implementation of Fuzzy Logic Control into an Equivalent Minimization Strategy for Adaptive Energy Management of A Parallel Hybrid Electric Vehicle
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作者 Jared A. Diethorn Andrew C. Nix +1 位作者 Mario G. Perhinschi W. Scott Wayne 《Journal of Transportation Technologies》 2024年第1期88-118,共31页
As government agencies continue to tighten emissions regulations due to the continued increase in greenhouse gas production, automotive industries are seeking to produce increasingly efficient vehicle technology. Hybr... As government agencies continue to tighten emissions regulations due to the continued increase in greenhouse gas production, automotive industries are seeking to produce increasingly efficient vehicle technology. Hybrid electric vehicles (HEVs) have been introduced to mitigate problems while improving fuel economy. HEVs have led to the demand of creating more advanced controls software to consider multiple components for propulsive power in a vehicle. A large section in the software development process is the implementation of an optimal energy management strategy meant to improve the overall fuel efficiency of the vehicle. Optimal strategies can be implemented when driving conditions are known a prior. The Equivalent Consumption Minimization Strategy (ECMS) is an optimal control strategy that uses an equivalence factor to equate electrical to mechanical power when performing torque split determination between the internal combustion engine and electric motor for propulsive and regenerative torque. This equivalence factor is determined from offline vehicle simulations using a sensitivity analysis to provide optimal fuel economy results while maintaining predetermined high voltage battery state of charge (SOC) constraints. When the control hierarchy is modified or different driving styles are applied, the analysis must be redone to update the equivalence factor. The goal of this work is to implement a fuzzy logic controller that dynamically updates the equivalence factor to improve fuel economy, maintain a strict charge sustaining window of operation for the high voltage battery, and reduce computational time required during algorithm development. The adaptive algorithm is validated against global optimum fuel economy and charge sustaining results from a sensitivity analysis performed for multiple drive cycles. Results show a maximum fuel economy improvement of 9.82% when using a mild driving style and a 95% success rate when maintaining an ending SOC within 5% of the desired SOC regardless of starting SOC. 展开更多
关键词 Hybrid Electric Vehicle Fuzzy Logic Adaptive control Charge Sustainability
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Flexible predictive power-split control for battery-supercapacitor systems of electric vehicles using IVHS 被引量:1
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作者 HE Defeng LUO Jie +1 位作者 LIN Di YU Shiming 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2023年第1期224-235,共12页
The utilization of traffic information received from intelligent vehicle highway systems(IVHS) to plan velocity and split output power for multi-source vehicles is currently a research hotspot. However, it is an open ... The utilization of traffic information received from intelligent vehicle highway systems(IVHS) to plan velocity and split output power for multi-source vehicles is currently a research hotspot. However, it is an open issue to plan vehicle velocity and distribute output power between different supply units simultaneously due to the strongly coupling characteristic of the velocity planning and the power distribution. To address this issue, a flexible predictive power-split control strategy based on IVHS is proposed for electric vehicles(EVs) equipped with battery-supercapacitor system(BSS). Unlike hierarchical strategies to plan vehicle velocity and distribute output power separately, a monolayer model predictive control(MPC) method is employed to optimize them online at the same time. Firstly, a flexible velocity planning strategy is designed based on the signal phase and time(SPAT) information received from IVHS and then the Pontryagin’s minimum principle(PMP) is adopted to formulate the optimal control problem of the BSS. Then, the flexible velocity planning strategy and the optimal control problem of BSS are embedded into an MPC framework, which is online solved using the shooting method in a fashion of receding horizon. Simulation results verify that the proposed strategy achieves a superior performance compared with the hierarchical strategy in terms of transportation efficiency, battery capacity loss, energy consumption and computation time. 展开更多
关键词 electric vehicle(EV) model predictive control(MPC) Pontryagin’s minimum principle(PMP) power-split
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Research on Electrical Automation Control Design Based on PLC Technology
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作者 He Yu 《Journal of Electronic Research and Application》 2024年第4期174-179,共6页
As science and technology continue to progress forward,electrical automation engineering is also developing,of which programmable logic controller(PLC)technology is widely being used.Through the integration of PLC tec... As science and technology continue to progress forward,electrical automation engineering is also developing,of which programmable logic controller(PLC)technology is widely being used.Through the integration of PLC technology and traditional electrical automation technology,good development of modern science and technology is promoted while traditional automation is preserved.The development of electrical engineering can greatly improve the strength of science,technology,and economy in our country.Based on PLC technology,this paper analyzes the design of electrical automation control. 展开更多
关键词 PLC technology electrical automation control DESIGN
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Synthesis of Fractional-order PI Controllers and Fractional-order Filters for Industrial Electrical Drives 被引量:1
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作者 Paolo Lino Guido Maione +2 位作者 Silvio Stasi Fabrizio Padula Antonio Visioli 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2017年第1期58-69,共12页
This paper introduces an electrical drives control architecture combining a fractional-order controller and a setpoint pre-filter. The former is based on a fractional-order proportional-integral(PI) unit, with a non-i... This paper introduces an electrical drives control architecture combining a fractional-order controller and a setpoint pre-filter. The former is based on a fractional-order proportional-integral(PI) unit, with a non-integer order integral action, while the latter can be of integer or non-integer type. To satisfy robustness and dynamic performance specifications, the feedback controller is designed by a loop-shaping technique in the frequency domain. In particular, optimality of the feedback system is pursued to achieve input-output tracking. The setpoint pre-filter is designed by a dynamic inversion technique minimizing the difference between the ideal synthesized command signal(i.e., a smooth monotonic response) and the prefilter step response. Experimental tests validate the methodology and compare the performance of the proposed architecture with well-established control schemes that employ the classical PIbased symmetrical optimum method with a smoothing pre-filter. 展开更多
关键词 Dynamic inversion electrical drives fractionalorder PI controller LOOP-SHAPING set-point pre-filter
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Sliding Mode Control Approach for Electrically Controllable Clutch of AMT Based on the Feedback Linearization 被引量:1
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作者 程东升 张建武 +1 位作者 叶晓峰 黄维纲 《Journal of Donghua University(English Edition)》 EI CAS 2003年第3期88-93,共6页
A sliding mode control approach based on the feedback linearization is proposed for the electrically controllable clutch of AMT vehicles. The nonlinear dynamic model for the hydraulic actuator associated with clutch i... A sliding mode control approach based on the feedback linearization is proposed for the electrically controllable clutch of AMT vehicles. The nonlinear dynamic model for the hydraulic actuator associated with clutch is established. By means of the exact feedback linearization procedure of differential geometry, an equivalent, fully controllable and linear model is derived via a homomorphic transformation for the AMT clutch system.Furthermore, a sliding mode control is introduced to improve robustness. The tracking tests are performed using the sliding mode control on a Santana LX passenger car, and the experimental results prove that this nonlinear controller is of fine robustness and high degree of tracking accuracy. 展开更多
关键词 electrically controllable clutch exact feedback linearization sliding mode control ROBUSTNESS
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Real-time and wearable functional electrical stimulation system for volitional hand motor function control using the electromyography bridge method 被引量:5
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作者 Hai-peng Wang Zheng-yang Bi +3 位作者 Yang Zhou Yu-xuan Zhou Zhi-gong Wang Xiao-ying Lv 《Neural Regeneration Research》 SCIE CAS CSCD 2017年第1期133-142,共10页
Voluntary participation of hemiplegic patients is crucial for functional electrical stimulation therapy.A wearable functional electrical stimulation system has been proposed for real-time volitional hand motor functio... Voluntary participation of hemiplegic patients is crucial for functional electrical stimulation therapy.A wearable functional electrical stimulation system has been proposed for real-time volitional hand motor function control using the electromyography bridge method.Through a series of novel design concepts,including the integration of a detecting circuit and an analog-to-digital converter,a miniaturized functional electrical stimulation circuit technique,a low-power super-regeneration chip for wireless receiving,and two wearable armbands,a prototype system has been established with reduced size,power,and overall cost.Based on wrist joint torque reproduction and classification experiments performed on six healthy subjects,the optimized surface electromyography thresholds and trained logistic regression classifier parameters were statistically chosen to establish wrist and hand motion control with high accuracy.Test results showed that wrist flexion/extension,hand grasp,and finger extension could be reproduced with high accuracy and low latency.This system can build a bridge of information transmission between healthy limbs and paralyzed limbs,effectively improve voluntary participation of hemiplegic patients,and elevate efficiency of rehabilitation training. 展开更多
关键词 nerve regeneration functional electrical stimulation logistic regression rehabilitation of upper-limb hemiplegia electromyography control wearable device stroke frequency-modulation stimulation hand motion circuit and system real-time neural regeneration
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Hopf Bifurcation Analysis and Control for Electrical System of Military Vehicle
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作者 王宝华 杨成梧 《Defence Technology(防务技术)》 SCIE EI CAS 2009年第4期246-250,共5页
Electrical system of military vehicle is a typical parameterized nonlinear system where complicated bifurcations may exist and threaten its safe and stable operation. An algebraic criterion for Hopf bifurcation is pre... Electrical system of military vehicle is a typical parameterized nonlinear system where complicated bifurcations may exist and threaten its safe and stable operation. An algebraic criterion for Hopf bifurcation is presented briefly and applied to find Hopf bifurcation point of the electrical system with automatic voltage regulator(AVR) dynamics in military vehicle. Hopf bifurcation controllers are designed for this electrical system by using wash-out filter,linear feedback,nonlinear feedback and their combination. The linear feedback control makes the system bring Hopf bifurcation at preferable parameter,the nonlinear feedback control modifies the type of the bifurcation,and the wash-out filter enhances the system damping,thus,the Hopf bifurcation is eliminated and the electrical system stability is ensured. Simulation results show the controller's validity. 展开更多
关键词 automatic control technology electrical system of military vehicles Hopf bifurcation bifurcation control STABILITY
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Analysis of Control Characteristic for the Drive System of Electric Transit Bus
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作者 张承宁 李红林 +1 位作者 孙逢春 张旺 《Journal of Beijing Institute of Technology》 EI CAS 2003年第3期302-306,共5页
The drive control system of the permanent magnetic direct current motor with the enhanced magnetism windings used in the electric transit bus is developed. The mathematics model of the drive control system for this mo... The drive control system of the permanent magnetic direct current motor with the enhanced magnetism windings used in the electric transit bus is developed. The mathematics model of the drive control system for this motor is established. The new mode that the added exiting magnetism field could be weakened and the speed of the motor could be controlled automatically is proposed and realized. The method of root locus design is applied to analyze the acceleration control characteristic. The results of simulation show that the new drive motor control system has extraordinary response characteristic and adjustable performance. Experiments of vehicle running show that the drive control system's antijamming ability is strong and the adjustable performance is fast and smooth, it can meet the demand of power characteristic very well. 展开更多
关键词 control characteristic electric transit bus enhanced magnetism motor drive system transfer function root trace
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The Electrical and Mechanical Alignment and Accuracy Detection of Numerial Control Machine Tool 被引量:1
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作者 XU Liang-xiong ZHOU Xiang 《International Journal of Plant Engineering and Management》 2012年第1期44-49,共6页
In the work of numerical control reformation of general machine tool, the installation and debugging of machine tool is a crucial part. For the C6132 machine tool, and make the use of electrical and mechanical alignme... In the work of numerical control reformation of general machine tool, the installation and debugging of machine tool is a crucial part. For the C6132 machine tool, and make the use of electrical and mechanical alignment, parameter adjusting, numerical control lathe accuracy debugging and performance examination has been used to finish a series of tailing in the work of numerical control reformation of general machine tool. In this paper, the detailed process of electrical and mechanical alignment, parameter adjusting, numerical control lathe accuracy debugging and performance examination has been demonstrated, meanwhile, the specific operational approach of these work programs has been discussed. Therefore, the present results provides essential reference and approach for the numerical control reformation of general machine tool. 展开更多
关键词 electrical and mechanical alignment parameter adjusting numerical control lathe accuracy debugging and performance examination
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The Design of New Sensorless BLDCM Control System for Electric Vehicle
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作者 Zhibin Ren Xiping Liu 《Energy and Power Engineering》 2010年第3期208-212,共5页
In order to meet the requirement of reliably running which is by Electric Vehicle for motor controller, the paper is focused on a sensorless brushless DC motor controller design and a commutation point method. By util... In order to meet the requirement of reliably running which is by Electric Vehicle for motor controller, the paper is focused on a sensorless brushless DC motor controller design and a commutation point method. By utilizing the saturation effect of stator iron core, six short voltage pulses are employed to estimate the initial rotor position. After that a series of voltage pulses are used to accelerate the motor. When the motor reaches a certain speed at which the back-electromotive force (EMF) method can be applied, the running state of the motor is smoothly switched at the moment determined by the relationship between the terminal voltage waveform and the commutation phases. “Lagging 90?-α commutation” is bring forward to overcome the shortages existing in the traditional method. The experimental results verify the feasibility and validity of the proposed method. 展开更多
关键词 BRUSHLESS DC MOTOR Electric Vehicle Ensorless control COMMUTATION POINT
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Evaluation of the Severity of Maxillo-Facial Injuries by Motorcycle Road Accident in the Teaching Hospital of Conakry: A Case-Control Study
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作者 Oumar Raphiou Diallo Alpha Oumar Diallo +1 位作者 Karamoko Alpha Diallo Alhassane Conde 《Open Journal of Stomatology》 2021年第3期107-118,共12页
<b><span>Introduction:</span></b><span> Maxillofacial injuries caused by motorcycle road accidents are serious and represent a real public health issue. They mainly affect young adul... <b><span>Introduction:</span></b><span> Maxillofacial injuries caused by motorcycle road accidents are serious and represent a real public health issue. They mainly affect young adult males. The objectives of this study were to determine the frequency of motorcycle road accidents, describe the socio-demographic characteristics of the injured, determine the degree of severity of motorcycle injuries compared to car injuries, and describe the therapeutic modalities.</span><span> </span><b><span>Materials and Method:</span></b><span> This study was a prospective case-control study carried out in the Department of Odontostomatology, Maxillofacial Surgery and Surgical Emergencies at the National Hospital of Donka. The data w</span><span>as</span><span> collected over a period of six months from January 1st to June 30th, 2017. All victims of road accidents by motorcycle (cases) or car (controls) that received care and post-surgical follow up were included.</span><span> </span><b><span>Results: </span></b><span>A total of 505 patients with maxillofacial injuries were reviewed during the period of the study.</span><span> </span><span>From the review, 205 (40.6%) motorcycle accidents were recorded as “cases” and 109 (21.58%) car accidents were classified as “controls” group. Men were the most affected in both groups, n = 254 (177 males in the case group and 77 in the control) (p = 0.01). There was a proportionate relationship between helmet use and death (p = 0.015). A motorcycle accident victim is more likely to develop a mandibular fracture (p = 0.029) and limb injury (p = 0.034) when compared to a car accident victim. However, there was no significant difference between cases and controls for head trauma (p = 0.4878), Facial Injury Severity Scale (FISS) (p = 0.130), and Glasgow score (p = 0.709).</span><span> </span><b><span>Conclusion:</span></b><span> Maxillofacial injuries caused by motorcycle accidents </span><span>are</span><span> increasing </span><span>in</span><span> Guinea. Young adult males have the highest incidence </span><span>of</span><span> motorcycle accidents. The death rate related to motorcycle road accidents is high, and mandatory use of a helmet for all drivers and passengers is recommended. These preventative actions could reduce the mortality and morbidity of motorcycle road accidents in Guinea.</span> 展开更多
关键词 SEVERITY Maxillofacial Trauma motorcycle CASE-control
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