Control Of Dynamic System Research Articles

Dynamic human systems risk prognosis and control of lifting operations during prefabricated building construction

Prefabricated building construction (PBC) involves tedious lifting operations that require multiple cranes to work simultaneously in dynamic workspaces. Such operations involve frequent interactions among human, cyber, and physical environments, creating challenges for risk prognosis and control in dynamic contexts. Unfortunately, human errors pose challenges for achieving resilient lifting operation control. A dynamic human systems risk prognosis and control (DHS RP & C) approach is thus necessary for 1) capturing human errors and 2) controlling risks of human anomalies proactively. This study critically reviews opportunities and challenges for establishing the proposed approach. Challenges exist as 1) how to collect human/team behavior data during lifting operations, 2) how to analyze these data for comprehending the impacts of human factors, and 3) how to respond to operational contingencies with risk control measures. In the end, the authors established a research roadmap for guiding future research activities toward automated lifting operations in PBC.

Dynamic event-triggered formation control of second-order nonholonomic systems

Dynamic event-triggered formation control of second-order nonholonomic systems

Modeling and dynamic safety control of compressed air energy storage system

Energy process system positively contributes to the energy utilization efficiency, the energy complement, and the construction of a low-carbon sustainable energy system. The multiple energy subsystems are deep interdependent, therefore, significant operational risks exist in the energy process system. To avoid system risk and fulfill operation requirement, we propose the Safety-Index based model predictive control that coordinates the controller design and system safety in this work. The innovation of the method is to integrate the state-space model of process system with advanced controller design while accounting for system safety. Since the state-space model of the energy process system is described by coupled partial differential equations and ordinary differential equations, which leads to difficulties in modeling and solving, the main contribution of this work is to simplify the constrained optimization problem formed by model predictive controller. The paper addresses the compressed air energy storage system as case study. From the numerical simulations of the safety controller performance, it shows that the system safety can be guaranteed by control strategy which realizes the system operation target and reject the system external disturbances, which caused by environmental or operation change.

ИНТЕЛЛЕКТУАЛЬНОЕ ПЛАНИРОВАНИЕ СТРАТЕГИЙ И УПРАВЛЕНИЕ ГРУППОЙ МОБИЛЬНЫХ РОБОТОВ В УСЛОВИЯХ НЕПОЛНОТЫ ИНФОРМАЦИИ

Different problems of strategy planning and control of a mobile robot group under complex dynamicconditions with incomplete information about the external environment are considered. Approachesto solving problems of effective work scheduling under conditions of inconstant active groupcomposition, searching for the source of a nonstationary concentration field, supervisory control ofdiscrete-event systems are presented. An original mathematical model formulated in terms of work-shiftscheduling problems and a problem-oriented modification of evolutionary algorithms with a specializedset of heuristics for its efficient solution are developed for the problem of scheduling top-level groupwork. Searching and monitoring the source of the nonstationary concentration field is carried out usinga decentralized multi-agent control strategy that combines elements of bionic and gradient approaches,as well as a method for generating artificial potential fields. The considered control strategy has lowcomputational complexity, high variability with respect to the types of fields surveyed, and is easily scalableto control any available number of mobile robots. The latter is of special importance, in particularwhen considering the problem of parallel and independent monitoring of multiple sources. It is proposedto use the means of logical inference, namely automatic theorem proving in the calculus of positivelyconstructed formulas, to solve various problems of the supervised control theory of discrete-eventsystems used at different levels of the robotic complex hierarchical control system. Features of the calculusallows solving complex problems of dynamic systems control, as well as processing and controllingevents based on environmental data in real time in the process of logical inference efficiently. Theapproach based on positively constructed formulas allows studying the properties of automata-baseddiscrete-event systems, as well as to synthesize and model finite automata for the construction and realizationof monolithic and modular supervisors. A general scheme combining the considered approachesfor controlling a group of mobile robots at different levels and time scales within a single hierarchicalcontrol system is proposed.

Distributed Dynamic Event-Triggered Control for Euler-Lagrange Multiagent Systems With Parametric Uncertainties.

This article investigates the distributed dynamic event-triggered control of networked Euler-Lagrange systems with unknown parameters. Using the designed dynamic event-triggered control algorithm, the leaderless consensus problem and the containment problem of networked Euler-Lagrange systems are solved, and the estimations of unknown parameters are updated by an adaptive updating law as well. The stability analysis is given based on an appropriate Lyapunov function and the distributed control problem is theoretically solved by the designed control algorithm. The Zeno behavior of the designed dynamic event-triggered method is excluded in a finite-time interval. Compared to some existing results for the event-triggered control of networked Euler-Lagrange systems, these event-triggered methods can be seen as the special cases of the dynamic event-triggered method proposed in this article. Simulation results based on UR5 robots of V-rep show that the proposed method can provide an increase (4.46 ± 3.36%) of the average lengths of event intervals compared to the one of the existing event-triggered methods, which leads to a lower usage of the communication resource. Meanwhile, the time of achieving the consensus/containment and the steady-state control performance are not affected.

Controllability of fractional dynamical systems with ψ-Caputo fractional derivative

The idea behind this study is to investigate the controllability of dynamical systems in terms of the ψ-Caputo fractional derivative. The Grammian matrix is used to get at necessary and sufficient controllability requirements for linear systems, which are characterized by the Mittag-Leffler functions, while the fixed point approach is used to arrive at adequate controllability criteria for nonlinear systems. The novelty of this research is to inquire into the controllability concepts by utilizing the ψ-Caputo fractional derivative. Since ψ-Caputo fractional derivatives have the advantage of capturing memory effects as well as increasing the accuracy of anticipating real-world scenarios. A few numerical examples are offered to help better understand the theoretical results.

Electromechanical Coupling Dynamic and Vibration Control of Robotic Grinding System for Thin-Walled Workpiece

The robotic grinding system for a thin-walled workpiece is a multi-dimensional coupling system composed of a robot, a grinding spindle and the thin-walled workpiece. In the grinding process, a dynamic coupling effect is generated, while the thin-walled workpiece stimulates elastic vibration; the grinding spindle, as an electromechanical coupling actuator, is sensitive to the elastic vibration in the form of load fluctuations. It is necessary to investigate the electromechanical coupling dynamic characteristics under the vibration coupling of the thin-walled workpiece as well as the vibration control of the robotic grinding system. Firstly, considering the dynamic coupling effect between the grinding spindle and thin-walled workpiece, a dynamic model of the grinding spindle and thin-walled workpiece coupling system is established. Secondly, based on this established coupling dynamic model, the vibration characteristics of the thin-walled workpiece and the electromechanical coupling dynamic characteristics of the grinding spindle are investigated. Finally, a speed adaptive control system for the grinding spindle is designed based on a fuzzy PI controller, which can achieve a stable speed for the grinding spindle under vibration coupling and has a certain suppression effect on the elastic vibration of the thin-walled workpiece at the same time.

Controllability and Observability Analysis of a Fractional-Order Neutral Pantograph System

In the recent past, a number of research articles have explored the stability, existence, and uniqueness of the solutions and controllability of dynamical systems with a fractional order (FO). Nevertheless, aside from the controllability and other dynamical aspects, very little attention has been given to the observability of FO dynamical systems. This paper formulates a novel type of FO delay system of the Pantograph type in the Caputo sense and explores its controllability and observability results. This research endeavor begins with the conversion of the proposed dynamical system into a fixed-point problem by utilizing Laplace transforms, the convolution of Laplace functions, and the Mittag–Leffler function (MLF). We then set out Gramian matrices for both the controllability and observability of the linear parts of our proposed dynamical system and prove that both the Gramian matrices are invertible, thus confirming the controllability and observability in a given domain. Considering the controllability and observability results of the linear part along with some other assumptions, we investigate the controllability and observability results related to the nonlinear system. The Banach contraction result, the fixed-point result of Schaefer, the MLF, and the Caputo FO derivative are used as the main tools for establishing these results. To establish the authenticity of the established results, we add two examples at the end of the manuscript.

Modeling and Control of Dynamic Wireless Power Transfer System for Electric Vehicle charger application

This paper proposes a nonlinear state-space model for a dynamic wireless power transfer system (DWPT). The DWPT system comprises emitter coils supplied by DC/AC converters, with a phase angle control to achieve maximum power transfer. The power receiver coil is connected to a full bridge diode rectifier followed by an equivalent load resistance. To emulate the dynamic movement property of WPT, the coupling factors between the emitter and receiver coils are set to be variable and depend on the movement of the power receiver alongside the power emitter coils. The control has been successfully demonstrated under variable coupling coefficients to achieve maximum power transfer. Such improvement maintains the power and voltage across the load during transient states.

Research on Mixed Logic Dynamic Modeling and Finite Control Set Model Predictive Control of Multi-Inverter Parallel System

Parallel connection of multiple inverters is an important means to solve the expansion, reserve and protection of distributed power generation, such as photovoltaics. In view of the shortcomings of traditional droop control methods such as weak anti-interference ability, low tracking accuracy of inverter output voltage and serious circulation phenomenon, a finite control set model predictive control (FCS-MPC) strategy of microgrid multi-inverter parallel system based on Mixed Logical Dynamical (MLD) modeling is proposed. Firstly, the MLD modeling method is introduced logical variables, combining discrete events and continuous events to form an overall differential equation, which makes the modeling more accurate. Then a predictive controller is designed based on the model, and constraints are added to the objective function, which can not only solve the real-time changes of the control system by online optimization, but also effectively obtain a higher tracking accuracy of the inverter output voltage and lower total harmonic distortion rate (Total Harmonics Distortion, THD); and suppress the circulating current between the inverters, to obtain a good dynamic response. Finally, the simulation is carried out on MATLAB/Simulink to verify the correctness of the model and the rationality of the proposed strategy. This paper aims to provide guidance for the design and optimal control of multi-inverter parallel systems.

Study on the symmetries and conserved quantities of flexible mechanical multibody dynamics

<abstract> <p>In this paper, in order to provides a powerful new tool for quantitative and qualitative analysis of dynamics properties in flexible mechanical multibody systems, the symmetry theory and numerical algorithms for preserving structure in modern analytical mechanics is introduced into flexible multibody dynamics. First, taking the hub-beam systems as an example, the original nonlinear partial differential-integral equations of the system dynamics model are discretized into the finite-dimensional Lagrange equations by using the assumed modal method. Second, the group analysis theory is introduced and the criterion equations and the corresponding conserved quantities of Noether symmetries are given according to the invariance principle, which provide an effective way for analytic integral theory of dynamic equations. Finally, a conserved quantity-preserving numerical algorithm is constructed by coordinates incremental discrete gradient, which makes full use of the invariance of conserved quantity to eliminate the error consumption for a long time. The simulation results show that the deeper mechanical laws and motion characteristics of flexible mechanical multibody systems dynamics can be obtained with the help of symmetries and conserved quantities, which can provide reference for more precise dynamic optimization design and advanced control of systems.</p> </abstract>

Prescribed Performance Dynamic Surface Control of Hydraulic-driven Barrel Servo System with Disturbance Compensation

Prescribed Performance Dynamic Surface Control of Hydraulic-driven Barrel Servo System with Disturbance Compensation

H-Infinity Electronic Controller Fails for Integrated Delay in Aircrafts

When the time delay is integrated into the dynamic system definition and the analysis of a complex dynamic system such as aircraft is carried out, it depicts that integrating the delay into the definition would be advantageous in evaluating the performance of the aircraft at a faster rate. It also stabilizes the plant at a faster rate when compared to classical control techniques applied on systems considering delay as a separate entity. An H-infinity controller is designed for the integrated system and analyzed as part of the studies that yielded interesting observations on the H-infinity limitations. The analysis of the system when compared to simple classical control techniques is vividly advantageous however when delays are integrated and critical delay impacts are not calculated, the chances for failure of a dynamic system control predominantly increase owing to varied complex governing equations which otherwise would be approximated with linear models.

Development of an Information Model of a Heat Supply System at Various Stages of the Life Cycle

Introduction. Data on elements of heat supply systems of the Russian Federation (heat sources, heating networks) are given as well as the main energy characteristics. The main problems in the industry are indicated. It is concluded that it is necessary to optimize the operation of heat supply systems in all its links and at all stages of the life cycle.Materials and Methods. For optimal control of thermal power systems, the authors consider it expedient to create a digital information model of each element of the system at each stage of the life cycle, including: - three-dimensional engineering digital terrain model; - three-dimensional engineering digital model of heating networks, taking into account adjacent communications and structures;- operational digital model of the heat supply system on the platform of the geoinformation software complex Zulu21. The technology of data exchange in IFC format between software complexes is given. The necessity of verification of the operational model using the data of field measurements on the physical model of the heat supply system is indicated.Results. The creation of a digital information 6D model of the heat supply system allows you to move to a higher level: intelligent dynamic control of a complex energy system (neurocontrol). The SCADA software package in online mode collects the necessary information (temperature, pressure, coolant flow) from sensors installed at characteristic points of the system. All information is transmitted to Zulu, a software package with built-in support for OPC technology to receive data from a SCADA system. The received data is fed into the ZuluGis software package, which includes the ZuluThermo module, with a loaded digital information model of the heat supply system. The actual thermal and hydraulic modes of the system are calculated in the module. Data on the optimal and actual thermal-hydraulic modes are transmitted to the neurofeedback unit for comparison and management decisionmaking. The decision is transmitted to the appropriate controller to initialize actions to change a parameter.Discussion and Conclusions. A technology for developing a digital information model for elements of a heat supply system at all stages of its life cycle is proposed. The creation of a digital information 6D model of the heat supply system allows you to move to a higher level: intelligent dynamic control of a complex energy system (neurocontrol). The use of intelligent control makes it possible to improve the quality of decisions made, significantly increase the energy efficiency of heat supply systems and the quality of services provided to the end user.

Existence, stability and controllability of piecewise impulsive dynamic systems on arbitrary time domain

The main objective of this article is to establish the existence of solutions, stability, and controllability results for piecewise nonlinear impulsive dynamic systems on an arbitrary time domain. Using the Banach fixed point theorem, we prove the existence of a unique solution while by applying Schauder’s fixed point theorem, we prove the existence of at least one solution. Further, we establish the controllability results by converting the controllability problem into a fixed point problem of an operator equation in some suitable function space. Mainly, we used the fixed point theorems, Gramian type matrices, functional analysis, and time scales theory to establish these results. Since the problem is formulated by using the theory of time scales, therefore, the obtained results are true for the continuous-time domain, discrete-time domain, as well as any combination of these two, which shows that the obtained results are non-trivial and generalize the existing ones. In the last, we have given a simulated example for two different time domains to verify the obtained analytical results.

Application of pseudoinverse matrices in optimal terminal control problems of linear discrete systems

The problem of linear-quadratic optimal terminal control of a linear discrete dynamic system with a vector input is considered. Solutions of the problem based on the apparatus of the optimization form of pseudo-circulation of matrices are given. The solution of the optimal terminal control problem is obtained, which ensures the achievement of the terminal control goal and the passage of the trajectory of the system as close as possible to the specified intermediate points. A complete set of solutions to the problem of optimal terminal control of a bundle of trajectories is obtained.

Active Vibration Control of Nonlinear Elastic Wire Rope in Mine Hoisting System

Based on the importance of the safe operation of the mine hoist mechanism, an adaptive control method based on Fuzzy Sliding Mode Control (FSMC) was applied to synchronize the large-amplitude response of geometrically nonlinear elastic wire rope in mine hoist systems. To efficiently and precisely synchronize the lateral vibration of a wire rope under the adaptive synchronizing method, the control equation of the elastic wire rope was given considering the large von Karman geometrical deformation, and it was converted to a six-dimensional nonlinear dynamical system using third-order Galerkin discretization. Based on this dynamic system, the existing FSMC is improved, so that the improved control strategy will be available for the active dynamic control of multidimensional nonlinear dynamical systems. The research shows that the control strategy can effectively synchronize the large-amplitude response of wire rope, thus providing the basis for dynamic design, fault diagnosis, and safe operation of the mine hoist system.

Adaptive Dynamic Surface Control of Strict-Feedback Fractional-Order Nonlinear Systems with Input Quantization and External Disturbances

In this work, an adaptive dynamic surface control law for a type of strict-feedback fractional-order nonlinear system is proposed. The considered system contained input quantization and unknown external disturbances. The virtual control law is presented by utilizing a dynamic surface control approach at each step, where the nonlinear compensating term with the estimation of unknown bounded parameters is introduced to overcome the influence of unknown external disturbances and surface errors. Meanwhile, the adaptive laws of relevant parameters are also designed. In addition, an improved fractional-order nonlinear filter is developed to deal with the explosion of complexity raised by the recursive process. In the last step, an adaptive dynamic surface control law is proposed to ensure the convergence of tracking error, in which the Nussbaum gain function is applied to solve the problem of the unknown control gain generated by input quantization. Then, the fractional Lyapunov stability theory is applied to verify the stability of the proposed control law. Finally, simulation examples are given to illustrate the effectiveness of the proposed control law.

Dynamic modeling and control of a two-reactor metal hydride energy storage system

Metal hydrides have been studied for use in energy storage, hydrogen storage, and air-conditioning (A/C) systems. A common architecture for A/C and energy storage systems is two metal hydride reactors connected to each other so that hydrogen can flow between them, allowing for cyclic use of the hydrogen. This paper presents a nonlinear dynamic model and multivariate control strategy of such a system. Each reactor is modeled as a shell-and-tube heat exchanger connected to a circulating fluid, and a compressor drives hydrogen flow between the reactors. We further develop a linear state–space version of this model integrated with a model predictive controller to determine the fluid mass flow rates and compressor pressure difference required to achieve desired heat transfer rates between the metal hydride and the fluid. A series of case studies demonstrates that this controller can track desired heat transfer rates in each reactor, even in the presence of time-varying circulating fluid inlet temperatures, thereby enabling the use of a two-reactor system for energy storage or integration with a heat pump.

Dynamic event-triggered adaptive output feedback control of uncertain nonlinear systems with intermittent observations

In this paper, the output feedback adaptive control problem of uncertain nonlinear system with event-sampled states is studied. Firstly, a novel intermittent-state observer is designed to estimate the unmeasurable states. Secondly, the nature of event-triggered makes the state signals discontinuous, rendering the traditional backstepping technique inapplicable as the derivatives of virtual control signals do not exist. To overcome this non-trivial obstacle, we consider the case without state-triggering in the previous n−1 steps of Lyapunov stability analysis, and reconstruct the actual controller by utilizing the triggered states signals in the last step. It can be demonstrated that all signals of the resulting closed-loop system are semi-globally uniformly ultimately bounded (SGUUB) under the derived event-triggered laws and the system performance can be improved by tuning design parameters properly. Simulation examples are shown to validate the efficacy of the proposed control scheme.