Design of a strip thickness control system for tandem cold mills using H∞ control techniques

2003 ◽  
Vol 217 (4) ◽  
pp. 319-327
Author(s):  
S S Kim ◽  
J S Kim ◽  
S Y Yang ◽  
B R Lee ◽  
K K Ahn
Keyword(s):  
Control System ◽  
High Performance ◽  
Control Method ◽  
Feedforward Control ◽  
Thickness Variation ◽  
Linear Quadratic ◽  
Design Procedures ◽  
Control Techniques ◽  
Multivariable Control Systems ◽  
Control Units

In order to meet the requirement for higher thickness accuracy in cold-rolling mill processes, it is strongly desired to have an increasing high performance in control units. To meet this requirement, an output regulating control system with a roll-eccentricity estimator for each rolling stand of tandem cold mills was considered. Assuming entry thickness variation as well as roll eccentricity to be the major disturbances, a synthesis of multivariable control systems is presented and based on H∞ control theory, which can reflect knowledge of the input direction and spectrum of disturbance signals on design. Then, to reject roll eccentricity effectively, a weight function having some poles on the imaginary axis is introduced. This leads to a non-standard H∞ control problem, and the design procedures for solving this problem are analytically presented. The effectiveness of the proposed control method is evaluated through computer simulations and compared with the conventional linear quadratic control and feedforward control methods for roll eccentricity.

Control of coagulation process by dual wavelength article analyzer

1997 ◽  
Vol 36 (4) ◽  
pp. 135-142 ◽  
Author(s):  
Norihito Tambo ◽  
Yoshihiko Matsui ◽  
Ken-ichi Kurotani ◽  
Masakazu Kubota ◽  
Hirohide Akiyama ◽  
...  
Keyword(s):  
Water Quality ◽  
Control System ◽  
Predictive Control ◽  
Control Method ◽  
Feedforward Control ◽  
Raw Water ◽  
Floc Size ◽  
Coagulation Process ◽  
Series Of Experiments ◽  
Size Data

A coagulation process for water purification plants mainly uses feedforward control based on raw water quality and empirical data and requires operator's help. We developed a new floc sensor for measuring floc size in a flush mixer to be used for floc control. A control system using model predictive control was developed on the floc size data. A series of experiments was performed to confirm controllability of settled water quality by controlling flush mixer floc size. An automatic control with feedback from the coagulation process was evaluated as practical and reliable. Finally this new control method was applied for actual plant and evaluated as practical.

Improvement Shifting Control of Continuously Variable Transmission (CVT) by Using PID, Pole Placement and LQG

2013 ◽  
Vol 446-447 ◽  
pp. 1165-1170
Author(s):  
Shu Yuan Ma ◽  
Bdran Sameh ◽  
Saifullah Samo ◽  
Aymn Bary
Keyword(s):  
Control System ◽  
Control Method ◽  
Operating Conditions ◽  
Pole Placement ◽  
Speed Ratio ◽  
Linear Quadratic ◽  
Linear Quadratic Gaussian ◽  
Variable Transmission ◽  
Simulation Results ◽  
Pole Placement Controller

In this paper, the CVT shifting control system based on vehicle operating conditions is modeled and simulated using MATLAB/SIMULINK. The modeling stage begins with the derivation of required mathematical model to illustrate the CVT shifting control system. Then, Linear Quadratic Gaussian (LQG), Proportional- Integrated-Derivative (PID) and Pole Placement are applied for controlling the shifting speed ratio of the modeled CVT shifting system. Simulation results of shifting controllers are presented in time domain and the results obtained with LQG are compared with the results of PID and Pole placement technique. Finally, the performances of shifting speed ratio controller systems are analyzed in order to choose which control method offers the better performance with respect to the desired speed ratio. According to simulation results, the LQG controller delivers better performance than PID and Pole Placement controller.

scholarly journals The Neural Network-Combined Optimal Control System of Induction Motor

2019 ◽  
Vol 9 (4) ◽  
pp. 2513
Author(s):  
Thang Nguyen Trong
Keyword(s):  
Neural Network ◽  
Optimal Control ◽  
Control System ◽  
Induction Motor ◽  
Control Method ◽  
Response Speed ◽  
The State ◽  
Linear Quadratic ◽  
Neuron Network ◽  
The Neural Network

<span lang="EN-US">This research aims to propose the optimal control method combined with the neuron network for an induction motor. In the proposed system, the induction motor is a nonlinear object which is controlled at each working point. At these working-points, the state equation of the induction motor is linear, so it is possible to apply the linear quadratic regular algorithm for the induction motor. Therefore, the parameters of the state feedback controller are the functions. The output-input relationships of these functions are set through the neural network. The numerical simulation results show that the quality of the control system of the induction motor is very high: The response speed always follows the desired speed with the short transition time and the small overshoot. Furthermore, the system is robust in the case of changing the load torque, and the parameters of the induction motor are incorrectly defined</span>

scholarly journals Real-Time Robust and Optimized Control of a 3D Overhead Crane System

Sensors ◽  
2019 ◽  
Vol 19 (15) ◽  
pp. 3429
Author(s):  
Arash Khatamianfar ◽  
Andrey V. Savkin
Keyword(s):  
Control System ◽  
Discrete Time ◽  
High Speed ◽  
High Performance ◽  
Feedforward Control ◽  
Torque Control ◽  
State Feedback Control ◽  
Control Technique ◽  
Joint Control ◽  
Overhead Crane

A new and advanced control system for three-dimensional (3D) overhead cranes is proposed in this study using state feedback control in discrete time to deliver high performance trajectory tracking with minimum load swings in high-speed motions. By adopting the independent joint control strategy, a new and simplified model is developed where the overhead crane actuators are used to design the controller, with all the nonlinear equations of motions being viewed as disturbances affecting each actuator. A feedforward control is then designed to tackle these disturbances via computed torque control technique. A new load swing control is designed along with a new motion planning scheme to robustly minimize load swings as well as allowing fast load transportation without violating system’s constraints through updating reference trolley accelerations. The stability and performance analysis of the proposed discrete-time control system are demonstrated and validated analytically and practically.

scholarly journals Design and Realize a Snake-Like Robot in Complex Environment

2019 ◽  
Vol 2019 ◽  
pp. 1-9 ◽  
Author(s):  
Bingqi Liu ◽  
Mingzhe Liu ◽  
Xianghe Liu ◽  
Xianguo Tuo ◽  
Xing Wang ◽  
...  
Keyword(s):  
Control System ◽  
Real Time ◽  
Information Acquisition ◽  
High Performance ◽  
Control Method ◽  
Control Function ◽  
Complex Environment ◽  
Real Time System ◽  
Performance Requirements ◽  
Time Image

Aiming at high performance requirements of snake-like robots under complex environment, we present a control system of our proposed design which utilizes a STM32 as the core processor and incorporates real-time image acquisition, multisensor fusion, and wireless communication technology. We use Solidworks to optimize the design of head, body, and tail joint structure of the snake-like robot. The system is a real-time system with a simple-circuit structure and multidegrees of freedom are attributed to the flawless design of control system and mechanical structure. We propose a control method based on our simplified CPG model. Meanwhile, we improve Serpenoid control function and then investigate how different parameters affect the motion gait in terms of ADAMS emulation. Finally, experimental results show that the snake-like robot can tackle challenging problems including multi-information acquisition and processing, multigait stability, and autonomous motion and further verify the reliability and accuracy of the system in our combinatory experiments.

Design of a Crab-Like Octopod Robot

2007 ◽  
Vol 10-12 ◽  
pp. 263-266 ◽  
Author(s):  
Hong Wen Ma ◽  
L.Q. Wang ◽  
D.L. Chen ◽  
X.W. Hao ◽  
H.W. Luo
Keyword(s):  
Control System ◽  
Pid Control ◽  
Control Method ◽  
Bottom Layer ◽  
The Body ◽  
Hierarchical System ◽  
Force Sensors ◽  
Body Structure ◽  
Individual Control ◽  
Control Units

A crab-like octopod robot is introduced in this paper. The body structure of the robot is simuliar with a real crab. Each leg has three jionts which are driven by servomotors. The control system is a distributed hierarchical system with a top layer as gait generator and a bottom layer as servomotor controller. The bottom layer has enght individual control units every of which can control three servomotors using PID control method. The sensor systerm is composed of force sensors mounted at the end of the leg and a inclinometer provides pitch and roll angles of the body.

Electrohydraulic Control of Alternator Drives with Wide Speed Range

1970 ◽  
Vol 3 (7) ◽  
pp. T113-T124 ◽  
Author(s):  
G. K. Steel
Keyword(s):  
Control System ◽  
Hydraulic System ◽  
High Performance ◽  
Feedforward Control ◽  
Transmission System ◽  
Prime Mover ◽  
Speed Range ◽  
Constant Output ◽  
The Moment ◽  
Wide Speed Range

Consideration is given to the problem of controlling the output speed of a hydraulic transmission system, when the main source of disturbance is the changing speed of the prime-mover. A control system is described which will maintain a constant output speed over a range of input speeds of the order of 10:1. It is shown that satisfactory performance cannot be achieved over this wide speed range by using normal feedback control. The addition of a feedforward control operation overcomes this difficulty and yields a system which offers high performance. This system is particularly advantageous when the moment of inertia of the driven load is high. The control system has been realised in the form of an electro-hydraulic system and the results of tests on a typical transmission system are presented.

scholarly journals Sparse in the Time Stabilization of a Bicycle Robot Model: Strategies for Event- and Self-Triggered Control Approaches

Robotics ◽  
2018 ◽  
Vol 7 (4) ◽  
pp. 77 ◽  
Author(s):  
Joanna Zietkiewicz ◽  
Dariusz Horla ◽  
Adam Owczarkowski
Keyword(s):  
Control System ◽  
Energy Efficient ◽  
Research Field ◽  
Linear Quadratic Control ◽  
Linear Quadratic ◽  
Control Techniques ◽  
Efficient Control ◽  
Triggering Conditions ◽  
Standard Linear ◽  
New Research

In this paper, the problems of event- and self-triggered control are studied for a nonlinear bicycle robot model. It has been shown that by applying control techniques based on triggering conditions, it is possible to reduce both state-based performance index, as well as the number of triggers, in comparison to a standard linear-quadratic control which consumes less energy of the control system and decreases the potential mechanical wear of the robot parts. The results presented in this paper open a new research field for further studies, as discussed in the Summary section, and form the basis for further research in energy-efficient control techniques for stabilizing a bicycle robot.

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