Design Of Closed-loop Control System Research Articles

Closed-loop Control System Design of Wind Rope Hoisting of Transmission Tower

Abstract The traditional wind rope (tricing pendant) hoisting method of power transmission towers mainly relies on manpower to observe the posture of the hanger and adjust the retraction and release speed of the control rope, so as to avoid the scraping of hanger and the assembled tower body. In this paper, the ADAMS/Cable modeling tool is used to establish the transmission tower hoisting dynamic model with the JC27151CG tower as the object, and the reasonable installation position of the tricing pendant retraction system is analyzed. And based on the reasonable installation position, the hoisting strategy and hoisting control system of JC27151CG tower are studied. The main control system hardware of the control device mainly includes Delta PLC, servo driver, AC contactor and DC relay. The main control program is divided into two modes, manual and automatic, with a closed-loop control servo motor system. The manual mode operates the servo motor through buttons to realize forward and reverse rotation. In automatic mode, the system intelligently adjusts the lifting speed and attitude according to the data of the navigation system to ensure a smooth and safe lifting process. The research outcomes not only offer novel theoretical perspectives and methods for the hoisting of power transmission towers but also provide robust technical support for practical engineering operations.

A new time-domain robust anti-windup PID control scheme for vibration suppression of building structure

Robustness is one of the main issues in the design of closed-loop control systems, and to provide it, considering the differences between the actual and mathematical models, effects of external disturbances and measurement noise is necessary. In this study, a new time-domain robust anti-windup proportional integral derivative (PID) control scheme for vibration suppression of building structure is introduced. Because of computational complexity in determining and tuning gains of the controller for each structural vibration modes in the conventional PID control methods. Such as modal analysis; the dynamic vibration equations of the structure are implemented in the state space form to consider the effects of all vibration modes of the structural system in the controlling gains simultaneously. Uncertainties in the structural stiffness parameter, sensing noise, input time-delay, and saturation windup of the actuator are considered in a new formulation. To ensure robust stability and performance of the proposed controller, the closed-loop transfer function from exogenous inputs to the controlled outputs is defined as in the standard form of the H∞ mixed sensitivity minimization criterion. The PID control gains are obtained by minimizing the infinity norm of the closed-loop transfer function of the control system in standard form. Based on numerical study of an 11-story benchmark structure equipped with an active tuned mass damper, the robustness and stability of the proposed controller are presented. This controller can reduce further the maximum displacement, velocity, and acceleration of the structure subjected to far field earthquakes with considering uncertainties by 16, 10, and 16%, respectively, compared to the conventional PID controller.

Closed-Loop Control System Design for Wireless Charging of Low-Voltage EV Batteries with Time-Delay Constraints

This paper presents an inductive power transfer system on the basis of a double single-phase three-level T-type inverter and two split transmitting coils for constant current and constant voltage wireless charging of low-voltage light electric vehicle batteries with closed-loop control, considering time-delay communication constraints. An optimal control structure and a modified control strategy were chosen and implemented to the wireless power transfer system as a result of a review and analysis of existing solutions. The control system analysis and adjustment of the coefficients of the regulator using Laplace transform were performed. Our study addressed the behavior of the control system with different time delays as well as the dynamic response of the system. The detecting algorithm of a secondary coil was proposed, which ensured efficient system operation and increased the functionality, safety and usability of the device. The efficiency of energy transfer of 90% was reached at the transmitted power of 110 W, which is at the level of existing solutions considered in the article and opens the way to the commercialization of the proposed solution. Therefore, the feasibility of using a nonclassical multilevel inverter, together with split transmitting coils for wireless charging was confirmed.

Research of Forecasting Information Time Delays with Nenural Network in Telecontrol System

Abstract Aiming at the issues of random delay and delay uncertainty in both the before channel and feedback channel for network control system, the root causes of random delay influence closed-loop control system by case is analysis, and the predictive control method based on neural network to solve the feasibility of existence network random delay in control system closed-loop control has provided. Simulation results show that the method can reflect and predict the delay characteristics of between measurement data represents the network path, and can effectively substitute for the actual network in the design of closed-loop control system based on Internet to research; the method used fast and accurate can be used for online learning network model and forecast the network delay value, provides a new way to remote closed-loop control based on Internet.

The Analysis and Design of Closed-Loop Control System for MEMS Vibratory Gyroscopes

A digital closed-loop control system with all digital phase locked loop (ADPLL) is designed and optimized, in order to improve the bias stability and transient response of the gyroscope. The nonlinear mathematical models for the closed-loop amplitude and phase control system are established. The linearization method is applied to analyze the nonlinear models. The control parameters of the drive loop are optimized. The experimental results show that the phase deviation between the demodulation reference signal of the drive loop and the sense signal is less than 0.25° in the temperature range from-40°C to 60°C, within 0.15° of the variation. At room temperature, the overshoot amount of the gyroscope control system is 4.5% with setting time of 0.12s. The bias stability is 1.45°h. Compared to the analog control scheme, the digital control system has advantages of short setting time, small overshoot, short phase locked time, large locked range, high phase precision, etc.

The Research of Information Delay in the Neural Network Forecast Remote Control System

Abstract Aiming at the issues of random delay and delay uncertainty in both the before channel and feedback channel for network control system, the root causes of random delay influence closed-loop control system by case is analysis, and the predictive control method based on neural network to solve the feasibility of existence network random delay in control system closed-loop control has provided. Simulation results show that the method can reflect and predict the delay characteristics of between measurement data represents the network path, and can effectively substitute for the actual network in the design of closed-loop control system based on Internet to research; the method used fast and accurate can be used for online learning network model and forecast the network delay value, provides a new way to remote closed-loop control based on Internet.

Design of closed-loop control system for a bidirectional full bridge DC/DC converter

Bi-directional full bridge DC/DC converter is a nonlinear time-varying system. To design the closed-loop control system, it needed to be transformed into a continuum mathematical model. This paper proposed a modeling method by using state space average method and the small signal analysis method to build the model. Firstly, a nonlinear mathematical model of the converter was established by using the state space average method, and on this basis, using small signal analysis method to convert the nonlinear mathematical model to a continuum mathematical model. Then the stability criterion of the system is proposed and the PID parameters were adjusted by combining with the automatic control theory. Furthermore the digital closed-loop network of each working mode is designed. Finally by simulation and a series prototype experiments, the results verified the feasibility of closed-loop control system and the DC/DC converter.

Programming (FPGA) Platform Control for Petrol Pumping

the field programmable gate array (fpga) is an integrated circuit designed to be configured after manufacturing. The fpga configuration is generally specified using a verilog hardware description language (vhdl), similar to that used for an application-specific integrated circuit (asic). Fpgas can be used to implement any logical function that an asic could perform. Fpgas contain programmable components called logic blocks, and a hierarchy of reconfigurable interconnects that allows the blocks to be wired together—somewhat like many (changeable) gates that can be inter-wired in (many) different configurations . Logic blocks can be configured to perform complex combinational functions, or merely simple gates . In most fpgas, the blocks also include memory elements, which may be simple flip-flops or more complete blocks of memory. There are numerous options for designers in selecting a hardware platform for custom electronics design, ranging from embedded processors, application specific integrated circuits (asics), programmable microprocessor, fpgas to programmable devices (plds). The decision to choose a specific technology such as an fpga should depend primarily on the design requirements. Therefore, if the hardware requirements require a higher level of performance, then the fpga offers a suitable level of performance. (4) The definition of the behavior of the fpga is performed by programming it by a very high speed integrated circuit hardware description language (vhdl).(1) This paper deals with using the fpga as a means for petrol pumping .the embedded system based on the fpga is programmed to offer safe pumping .the fpga senses the conditions of the petrol pumping pipes in order to offer secure pumping .wireless smart sensors are mounted on the petrol pumping pipe. The aim of the design is to mainly avoid pipes damage or explosion due to mal functions of pumping. I. Problem statement: Secure petrol pumping in the pipes is a challenging issue .a proposed solution is based on using multi- sensing control system based on fpga . The embedded system gives a real time response based on the data acquisition from the wireless smart sensors mounted on the pipe . The high speed of processing of the fpga offers an instantaneous response for any data coming from the smart sensors. II. Methodology: This paper explains the approach for the design based on the fpga platform .the aim of the complete design is to offer maximum safety for the petrol pumping process. A closed loop control system design is adapted . A number of smart sensors are installed on the petrol pumping pipe . The smart sensors provide the fpga with an instantaneous data showing the status and condition of the pipe .the sensors are connected to the fpga through a data acquisition interface circuit designed to provide the data . According to this design the fpga will be able to monitor and control the petrol pumping process instantaneously. Hence the embedded system offers a real time monitoring and control for the petrol pumping operation. The following block diagram figure (1) shows the basic parts of this design.

Clinical Decision Support and Closed‐Loop Control for Intensive Care Unit Sedation

AbstractCritical care patients undergoing surgery require drug administration to regulate physiological variables such as blood pressure, cardiac output, heart rate, and degree of consciousness. The rate of infusion of each administered drug is critical, requiring constant monitoring and frequent adjustments. Patients in the intensive care unit who require mechanical ventilation due to acute respiratory failure also frequently require the administration of sedative agents. Open‐loop control (manual control) by clinical personnel can be tedious, imprecise, time‐consuming, and sometimes of poor quality, depending on the skills and judgment of the clinician. Dynamical system pharmacokinetic and pharmacodynamic modeling and closed‐loop control system design methodologies can significantly advance our understanding of the wide effects of pharmacological agents and anesthetics, as well as advance the state‐of‐the‐art in active control of drug delivery systems for clinical pharmacology. In this paper, we discuss the challenges and opportunities of clinical decision support and closed‐loop control for intensive care unit sedation.

The Application of PLC in the Stepper Motor Closed-Loop Control System Design

The application of PLC 、Stepper motor driver and Encoder are introduced in stepper motor closed-loop control system. The Principle diagram is analyzed, the Control System flow chart and Software program are designed. Through in-situ operation, the system has been proved well reliability、 stability and simplicity , achieved high accuracy and low cost requirements。

Computer-aided Simplification of High-order Linear Models

Models of many chemical processes are of high order. In order to simplify control laws for these systems and for practical implementation of the designed controllers, reduced-order or simplified models are sought. Many of the existing model reduction algorithms are computationally tasking, limited to rational systems, are fixed-parameter models, and involve a series of solution stages to the optimisation problem. This paper presents a very simple and effective computer-aided simplification (CAS) approach, the method of inequalities (MOI). For the past three decades, MOI has been applied to closed loop control system design, but not for solving model reduction problem. Hence, this work can be considered the first of its kind. A general multi-objective model reduction method is formulated for uncertain systems. The performance indices, which are defined as a set of algebraic inequalities, are defined as the sum of the squared errors between the output responses of the high-order uncertain systems and simplified uncertain systems. The simultaneous solution of these inequalities using moving boundaries process (MBP) in MATLAB environment yields stable optimal simplified models parameters. There is no need to monitor the stability of the reduced-order models during the course of iteration since the algorithm guarantees this. The effectiveness of the proposed approach is illustrated by means of three examples from the literature.

Continuous Drug Infusion for Diabetes Therapy: A Closed-Loop Control System Design

While a typical way for diabetes therapy is discrete insulin infusion based on long-time interval measurement, in this paper, we design a closed-loop control system for continuous drug infusion to improve the traditional discrete methods and make diabetes therapy automatic in practice. By exploring the accumulative function of drug to insulin, a continuous injection model is proposed. Based on this model, proportional-integral-derivative (PID) and fuzzy logic controllers are designed to tackle a control problem of the resulting highly nonlinear plant. Even with serious disturbance of glucose, such as nutrition absorption at meal time, the proposed scheme can perform well in simulation experiments.

Modeling and Control of a Wheel Loader With a Human-in-the-Loop Assessment Using Virtual Reality

This paper presents dynamic modeling, controller design, and virtual reality (VR)-based human-in-the-loop real-time simulation for a wheel loader control system. In particular, a loader with electrohydraulic actuation is considered. A detailed nonlinear dynamic model is developed for the hydraulic system and the loader linkage. The hydraulic model includes a load sensing pump, valves, and cylinders. The linkage model represents a two degree of freedom loader with lift and tilt functions. A linear quadratic Gaussian based robust controller is designed for automatic bucket leveling to assist the operator by keeping the angle of the bucket leveled while the boom is in motion. The closed-loop control system design is tested with a nonlinear model in a real-time VR simulation. In the VR simulation, the operator interacts with the model using a joystick input. The loader linkage geometry is displayed to the operator in real time using a VR display. The controller performance was assessed in the VR environment. As expected, the controller was found to provide a significant improvement in the accuracy of the bucket leveling, particularly in the case of a novice operator controlling the linkage motion. While prototypes cannot be eliminated, the VR simulation combined with realistic physics and control dynamics provided a useful tool for evaluating hydraulic systems and controls with less reliance on prototype machines.

Mechanical engineer's handbook

Preface Contributors 1. Statics Vector Algebra Centroids and Surface Properties Moments and Couples Equilibrium Dry Friction 2. Dynamics Fundamentals Kinematics of a Point Dynamics of a Particle Planar Kinematics of a Rigid Body Dynamics of a Rigid Body 3. Mechanics of Materials Stress Deflection and Stiffness Fatigue 4. Theory of Mechanisms Fundamentals Position Analysis Velocity and Acceleration Analysis Kinetostatics 5. Machine Components Screws Gears Springs Rolling Bearings Lubrication and Sliding Bearings 6. Theory of Vibration Introduction Linear Systems with One Degree of Freedom Linear Systems with Finite Numbers of Degrees of Freedom Machine-Tool Vibrations 7. Principles of Heat Transfer Heat Transfer Thermodynamics Conduction Heat Transfer Convection Heat Transfer 8. Fluid Dynamics Fluids Fundamentals Hydraulics 9. Control Introduction Signals Transfer Functions Connection of Elements Poles and Zeros Steady-State Error Time-Domain Performance Frequency-Domain Performances Stability of Linear Feedback Systems Design of Closed-Loop Control Systems by Pole-Zero Methods Design of Closed-Loop Control Systems by Frequential Methods State Variable Models Nonlinear Systems Nonlinear Controllers by Feedback Linearization Sliding Control Appendix: Differential Equations and Systems of Differential Equations Index

Automated Optimal Closed Loop Control System Design

This paper presents a design method for discrete event systems. The design method uses an arithmetic representation of Boolean functions (Franke 1994) to control the discrete event system. A closed loop control is achieved by predicting and evaluating future states of the system with respect to a desired performance index for the system to be controlled. This is done automaticall y and the method is therefore an attempt to ease the design of control systems for discrete event systems.

Vision-based remote control of cellular robots

This paper describes the development and design of a vision-based remote controlled cellular robot. Cellular robots have numerous applications in industrial problems where simple inexpensive robots can be used to perform different tasks that involve covering a large working space. As a methodology, the robots are controlled based on the visual input from one or more cameras that monitor the working area. As a result, a robust control of the robot trajectory is achieved without depending on the camera calibration. The remote user simply specifies a target point in the image to indicate the robot final position. We describe the complete system at various levels: the visual information processing, the robot characteristics and the closed loop control system design, including the stability analysis when the camera location is unknown. Results are presented and discussed. In our opinion, such a system may have a wide spectrum of applications in industrial robotics and may also serve as an educational testbed for advanced students in the fields of vision, robotics and control.

Modeling the hemodynamic response to dopamine in acute heat failure

A descriptive incremental nonlinear single-input-multiple-output (SIMO) model of the hemodynamic response [cardiac output (CO) and mean aortic pressure (MAP)] to the inotropic drug dopamine in acute ischemic heart failure was constructed to facilitate the design of closed-loop control systems. The structure of the CO component of the model is a first-order system with a sigmoidal relationship. The MAP component is a first-order system with a threshold. Parameter identification was performed on data collected during positive step (drug on) and negative step (drug off) testing using multiple levels (2-6 mcg/kg/min) of infusion of dopamine in a canine model of acute ischemic heart failure. Parameter estimation utilized a least squares objective function and a linearized form of the step response of the model in the time domain. The model provides good approximations to the mean empirical responses.

Practical method for optimal control of robot manipulators. 1st Report. Control law and digital simulation.

Optimal control strategies are very useful in manipulation problems of robots. However, most optimal controls are highly sensitive to plant-parameter variations and disturbances because optimal controls try to pick up exact information from the mathematical models in order to realize the best performance. We recognize that difficulties are involved in exact modeling of plants and prevention of disturbances. Therefore, we need a optimal control method with low sensitivity. The ideas of closed-loop control system design using LQG/TR techniques (linear quadratic Gaussian control with transfer recovery) are discussed in this paper. We combine optimal controls and LQG/TR control into two-degrees-of-freedom control systems to reduce the sensitivities of optimal control strategies. In digital simulations, we obtained excellent results of a two-link manipulator in an optimal time control problem using our method. Some modeling errors and considerable disturbances are allowed in the method. Thus, we can realize good performances in practical manipulation problems using our method.

Man-machine interaction in aerospace control systems

The Multi-Role Combat Aircraft Tornado is probably the most spectacular example to date of a complex man-machine system in which design and manufacture are widely dispersed. Even sub-assemblies of this system are extremely complex relative to the technology of just a few years ago. This makes life extremely difficult for an engineer involved in the procurement of the sub-assembly, especially as the overall objective can soon be submerged in a mass of detail. Starting with a review of desirable dynamic properties of the machine, as seen by the man, typical human operator transfer functions which have found use in closed-loop control system design are presented. Some ways in which microelectronics can reduce pilot work load are then discussed with the object of conveying to the design engineer some of the reasoning behind the performance specification he is trying to meet. Examples include helicopter stability augmentation systems and spacecraft terminal phase control.

Computer-aided design of closed-loop control systems: (A suite of programs developed at the University of Reading)

A suite of programs for c.a.d. of closed-loop control systems has been under development at the University of Reading, England. This paper describes the basic problems in the design of closed-loop control systems and explains how these can be solved far more rapidly by the use of an on-line computer with an interactive graphics system than by the use of hand-computation/computer-computation and hand-plotting of design graphs. A suite of programs for display of the Nyquist diagram, inverse Nyquist diagram, time-domain response and root-locus of single-loop systems with series or parallel compensation is summarized. A new method for analysing multi-loop systems using a graphical method of data capture is also included.