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IEEE TRANSACTIONS ON MEDICAL ROBOTICS AND BIONICS 2023年第3期5卷 547-562页

作者： Ahkami, Bahareh Ahmed, Kirstin Thesleff, Alexander Hargrove, Levi Ortiz-Catalan, Max Ctr Bion & Pain Res S-43130 Molndal Sweden Chalmers Univ Technol Dept Elect Engn S-41296 Gothenburg Sweden Integrum AB S-43153 Molndal Sweden Northwestern Univ Dept Phys Med & Rehabil Chicago IL 60611 USA Regenstein Fdn Ctr Bion Med Shirley Ryan AbilityLab Chicago IL 60611 USA Sahlgrens Univ Hosp Operat Area 3 S-41345 Gothenburg Sweden Bion Inst Melbourne VIC 3002 Australia

Most amputations occur in lower limbs and despite improvements in prosthetic technology, no commercially available prosthetic leg uses electromyography (EMG) information as an input for control. Efforts to integrate EMG signals as part of the control strategy have increased in the last decade. In this systematic review, we summarize the research in the field of lower limb prosthetic control using EMG. Four different online databases were searched until June 2022: Web of Science, Scopus, PubMed, and Science Direct. We included articles that reported systems for controlling a prosthetic leg (with an ankle and/or knee actuator) by decoding gait intent using EMG signals alone or in combination with other sensors. A total of 1,331 papers were initially assessed and 121 were finally included in this systematic review. The literature showed that despite the burgeoning interest in research, controlling a leg prosthesis using EMG signals remains challenging. Specifically, regarding EMG signal quality and stability, electrode placement, prosthetic hardware, and control algorithms, all of which need to be more robust for everyday use. In the studies that were investigated, large variations were found between the control methodologies, type of research participant, recording protocols, assessments, and prosthetic hardware.

关键词： Electromyography (EMG) pattern recognition lower limb amputation control architecture control algorithms movement intention recognition

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Position control of flexible robot arms using mechanical waves

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JOURNAL OF DYNAMIC SYSTEMS MEASUREMENT AND control-TRANSACTIONS OF THE ASME 1998年第3期120卷 334-339页

作者： O'Connor, W Lang, D Univ Coll Dublin Dept Mech Engn Dublin 4 Ireland

A novel position control strategy for flexible robot arms based on wave propagation and absorption techniques is presented. The arm is modeled by a lumped-parameter mass-spring system with an actuator at one end a,td a load mass at the other. The actuator is required to position the remote load and, simultaneously, to provide active vibration damping. Ir does so by propagating mechanical waves through the system and absorbing respected waves. Only the first two masses and springs need to be characterized and observed to determine the required actuator movement. The control algorithm is robust and compares very favorably with the time-optimal performance of bang-bang control. It is also inherently adaptive.

关键词： Position control Actuators Waves Damping Stress control algorithms Wave propagation Absorption Robots Vibration Springs

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Increasing the Economic Operation of Steam Turbines by Optimizing the Operating Modes of the control Stage

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THERMAL ENGINEERING 2020年第12期67卷 916-921页

作者： Turetskov, A. V. Shekhter, M. V. AO Ural Turbine Works Ekaterinburg 620017 Russia

Problems of ensuring the high efficiency of steam turbines during operation in partial modes are considered. It is noted that the decrease of steam throttling losses in the control valves has the greatest impact on the efficiency when operating in such modes. A brief overview of known techniques for increasing the efficiency of turbines by optimizing the operating modes of the control stage and the steam admission system, which consist in obtaining additional throttleless modes due to the combined operation of control stage nozzle boxes with different number of nozzles, is given. However, when implementing such techniques in dynamics, problems and limitations arise associated with the need for abrupt switching of control valves. A promising method (algorithm) for controlling the control valves of a steam turbine that ensures the optimization of the operating mode of the control stage and the minimum throttling losses in the control valves is proposed. The technology for implementation of the proposed control method, its advantages over the traditional one, and development prospects are stated. On the example of the T-295/335-23.5 turbine, the results of calculating the efficiency of the control stage with sequential and optimized steam admission, carried out by the proposed control method, are presented. The tests of optimized steam admission implemented by two methods, traditional and proposed one, are carried out on the mathematical model of T-295/335-23.5 turbine. The test results are presented in the form of graphs of transient processes. It is shown that, due to the optimization of steam admission by the proposed control algorithm for control valves, the disadvantages inherent in the implementation of the traditional method are eliminated, namely, the quality of transient processes is increased, there are no abrupt switching of control valves, the amplitude of steam temperature fluctuations in the nozzle boxes decreases, and it becomes possible to control the r

关键词： steam turbine control stage control system control valves turbine model optimization efficiency partial arc admission throttling control algorithms

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Feedforward and feedback control strategy for active noise cancellation in ducts

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JOURNAL OF DYNAMIC SYSTEMS MEASUREMENT AND control-TRANSACTIONS OF THE ASME 1996年第2期118卷 372-378页

作者： Hu, JS NATL CHAO TUNG UNIV DEPT CONTROL ENGNHSINCHUTAIWAN

This paper presents the theoretical work about active noise cancellation in ducts. The proposed control system is designed based on the assumption of a one-dimensional sound field. The controller consists of a feedforward block which serves as a noise observer. The feedback portion of the control algorithm is to minimize residual disturbances. Closed-loop stability of the MIMO (multiple-input-multiple-output) system is analyzed and the result shows that the dynamic influenced by the space-feedforward and feedback controllers can be decoupled. Both semi-infinite and finite-length ducts are considered in this study and simulation examples are given to illustrate the effectiveness of the proposed controllers.

关键词： Stability Noise (Sound) Ducts Simulation Feedforward control control algorithms control systems control equipment Feedback

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On the tracking control of differentially steered wheeled mobile robots

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JOURNAL OF DYNAMIC SYSTEMS MEASUREMENT AND control-TRANSACTIONS OF THE ASME 1997年第3期119卷 455-461页

作者： Zhang, YL Velinsky, SA Feng, X UNIV CALIF DAVIS DEPT MECH & AERONAUT ENGNDAVISCA 95616

Fundamental tracking control algorithms of a differentially steered wheeled mobile robot with two conventional driven wheels are studied through analyzing the robot's inherent kinematics. This includes the tracking variable assignment as well as the tracking singularity and position-orientation tracking decoupling problems. Globally convergent tracking control algorithms are proposed which can exactly track any differentiable reference path. A fundamental motion orientation equation under the condition of exact position tracking is developed, and it is shown that it is not possible to exactly track both position and orientation concurrently for this kind of mobile robot configuration if the tracking point is not on the baseline. Examples are provided illustrating the tracking ability of the developed control algorithms.

关键词： Tracking control control algorithms Kinematics Mobile robots Wheels algorithms

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DISCRETE control ALGORITHM FOR A HEAT-STORAGE SYSTEM

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JOURNAL OF DYNAMIC SYSTEMS MEASUREMENT AND control-TRANSACTIONS OF THE ASME 1980年第4期102卷 226-232页

作者： KULAKOWSKI, BT SCHMIDT, FW Department of Mechanical Engineering The Pennsylvania State University University Park Pa. 16802

The discrete control algorithm of a system incorporating a heat storage unit is presented. This system is required to supply thermal energy so that the given time varying load could be satisfied. A simple linear finite difference approximation of the process dynamics represented by the set of hyperbolic equations provides the basis for the control strategy. No initial knowledge of the values of the process parameters is necessary as the on-line identification procedure is incorporated in the control algorithm. The results of computer simulation indicate that the satisfactory performance of the system can be achieved even with a first order finite difference approximation of the heat storage unit behavior. A microprocessor-based system is recommended for implementation of the control algorithm.

关键词： Heat storage Dynamics (Mechanics) Stress control algorithms Thermal energy Approximation Computer simulation

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Learning the Optimal control for Evolving Systems with Converging Dynamics

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PROCEEDINGS OF THE ACM ON MEASUREMENT AND ANALYSIS OF COMPUTING SYSTEMS 2024年第2期8卷 1-39页

作者： Liu, Qingsong Fang, Zhixuan Tsinghua Univ Beijing Peoples R China Shanghai Qi Zhi Inst Shanghai Peoples R China

We consider a principle or controller that can pick actions from a fixed action set to control an evolving system with converging dynamics. The actions are interpreted as different configurations or policies. We consider systems with converging dynamics, i.e., if the principle holds the same action, the system will asymptotically converge (possibly requiring a significant amount of time) to a unique stable state determined by this action. This phenomenon can be observed in diverse domains such as epidemic control, computing systems, and markets. In our model, the dynamics of the system are unknown to the principle, and the principle can only receive bandit feedback (maybe noisy) on the impacts of his actions. The principle aims to learn which stable state yields the highest reward while adhering to specific constraints (i.e., optimal stable state) and to immerse the system into this state as quickly as possible. A unique challenge in our model is that the principle has no prior knowledge about the stable state of each action, but waits for the system to converge to the suboptimal stable states costs valuable time. We measure the principle's performance in terms of regret and constraint violation. In cases where the action set is finite, we propose a novel algorithm, termed Optimistic-Pessimistic Convergence and Confidence Bounds (OP-C2B), that knows to switch an action quickly if it is not worth waiting until the stable state is reached. This is enabled by employing "convergence bounds" to determine how far the system is from the stable states, and choosing actions through maintaining a pessimistic assessment of the set of feasible actions while acting optimistically within this set. We establish that OP-C2B can ensure sublinear regret and constraint violation simultaneously. Particularly, OP-C2B achieves logarithmic regret and constraint violation when the system convergence rate is linear or superlinear. Furthermore, we generalize our algorithm OP-C2B to the case

关键词： Evolving systems control algorithms Online learning

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A control THEORETIC STUDY ON DYNAMICAL BIPED LOCOMOTION

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JOURNAL OF DYNAMIC SYSTEMS MEASUREMENT AND control-TRANSACTIONS OF THE ASME 1980年第4期102卷 233-239页

作者： MIYAZAKI, F ARIMOTO, S Department of Mechanical Engineering Osaka University Toyonaka Osaka 560 Japan

The dynamics of the biped locomotion system with many degrees of freedom are analyzed from a control theoretic point of view. By the use of the singular perturbation technique, it is shown that biped locomotion can be divided into two modes with respective time scales, the fast mode and the slow mode. Based on this fact, a control system for dynamical biped locomotion is constructed. The effectiveness of the proposed control algorithm is verified using computer simulation.

关键词： Dynamics (Mechanics) control algorithms control systems Computer simulation Degrees of freedom

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control strategy for grid-connected DC-AC converters with load power factor correction

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IEE PROCEEDINGS-GENERATION TRANSMISSION AND DISTRIBUTION 1998年第5期145卷 487-491页

作者： Barbosa, PG Rolim, LGB Watanabe, EH Hanitsch, R Univ Fed Rio de Janeiro COPPE Dept Elect Engn BR-21945970 Rio De Janeiro Brazil Univ Fed Rio de Janeiro Dept Electrotech Sch Engn BR-21945970 Rio De Janeiro Brazil Tech Univ Berlin Inst Elekt Maschinen D-10587 Berlin Germany

The paper presents the modelling, analysis and design of a pulse width modulation voltage source inverter (PWM-VSI) to be connected between a DC source, which is supplied from a photovoltaic (PV) array and the AC grid. The control algorithm of the PWM-VSI applies the concepts of the instantaneous p-q (real-imaginary) power theory. The objective is to show that, with an adequate control, the converter can transfer the DC energy from PV array and improve the power factor (the power quality) of the electrical system. Some design considerations are also discussed. A digital simulation and measurements on a small prototype model verified the feasibility of the proposed control method.

关键词： grid-connected converters control algorithms modelling load power factor correction

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PRIME: a real-time cyber-physical systems testbed: from wide-area monitoring, protection, and control prototyping to operator training and beyond

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IET CYBER-PHYSICAL SYSTEMS: THEORY & APPLICATIONS 2020年第2期5卷 186-195页

作者： Becejac, Tamara Eppinger, Crystal Ashok, Aditya Agrawal, Urmila O'Brien, James Pacific Northwest Natl Lab Richland WA 99352 USA

As the power grid continues to evolve with advanced wide-area monitoring, protection, and control (WAMPAC) algorithms, there is an increasing need for realistic testbed environments with industry-grade software and hardware-in-the-loop (HIL) to perform verification and validation studies. Such testbed environments serve as ideal platforms to perform WAMPAC prototyping, operator training, and also to study the impacts of different types of cyberattack scenarios on the operation of the grid. In this study, the authors introduce pacific northwest national laboratory(PNNL) cyber-physical systems testbed (PRIME): the testbed that integrates real-time transmission system simulator with commercial industry-grade energy management system software and remote HIL (RHIL). PRIME is an end-to-end, modular testbed that allows high-fidelity RHIL experimentation of a power system. We present two detailed case studies (fault location and clearing in the transmission system and operator training) to show the capabilities of their PRIME testbed. Finally, we briefly discuss some of the potential limitations of their testbed in terms of scalability and flexibility to set up larger test systems and identify directions for future work to address these limitations.

关键词： smart power grids power system measurement power grids power system security distributed power generation power engineering computing fault location power system control power system simulation power distribution control energy management systems real-time cyber-physical systems testbed control prototyping operator training power grid advanced wide-area monitoring control algorithms WAMPAC realistic testbed environments industry-grade software hardware-in-the-loop validation studies ideal platforms cyberattack scenarios PNNL cyber integrates real-time transmission system commercial industry-grade energy management system software remote HIL modular testbed high-fidelity RHIL experimentation power system detailed case studies PRIME testbed larger test systems

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