Theoretical Control Design Research Articles

Research on the control problem of actuator anti-saturation of supercavitating vehicle.

In the theoretical controller design of the high-speed supercavitating vehicle (HSSV), there will always be the problem that the physical saturation limit has to be exceeded by the motion range of the actuator to satisfy the requirements of stable motion of the supercavitating vehicle. This paper proposes a solution which could satisfy the requirements of stable motion of the vehicle without saturation of the actuator. First of all, the rotation range of the actuator and the motion performance of the vehicle with robust controller are analyzed under the condition where saturation is neglected. Then, according to the analysis conclusion, the controller is improved by using linear active disturbance rejection control (LADRC) method, which provides the additional control component to reduce the rotation angle and rotation speed of the actuator. Finally, the simulation proves that the solution could realize the stable motion of vehicle without saturation of actuator.

Molten Metal Pressure Control for Defect Prevention with Generalized Predictive Control in Rapid Press Casting

This paper presents a technique for controlling the pressure of molten metal when using a new type of the iron production method called greensand mold press casting to realize high productivity and obtain high-quality castings. In this method, molten metal is poured into a lower mold first, and the after upper mold is moved down toward the lower mold, then both molds are matched. Casting defects such as metal penetration are often caused by the high pressure in the high-velocity pressing process. Therefore, we proposed a pressure control method with a mathematical model of molten metal pressure, and with it we achieved confirmation simulation of the successful pressing production at the different pressing condition such as mold shape. Results show that the proposed pressing production considering the generalized predictive control: GPC can realize sound, penetration-free casting production under the pressure constraint for defect prevention. Here a simple simulation of model predictive pressing control and water pressing experiment using feed-forward motion input calculated by off-line GPC are presented. Discussions of the theoretical control design for the process as well as its practical confirmation result of water pressure behavior in pressing experiment are concluded.

Trends in Theory of Control System Design Status report prepared by the IFAC Coordinating Committee on Design Methods

Control theory deals with disciplines and methods leading to an automatic decision process in order to improve the performance of a control system. The evolution of control engineering is closely related to the evolution of the technology of sensors and actuators, and to the theoretical controller design methods and numerical techniques to be applied in real time computing. New control disciplines, new development in the technologies will fertilize quite new control application fields. Based on the contributions of the Technical Committees within CC2 the status report gives an overview of the current key problems in control theory and design, evaluates the recent major accomplishments and forecasts some new areas. It points out some control fields, which could be challenges for future research.

Vehicle Motion Control Issues Using Micro Electric Vehicle “NOVEL”

This article describes the scope of vehicle dynamics control application on micro-scale electric vehicle for enhancing its active safety. The use of in-wheel-motor control in various control objectives as active safety devices are stated in the paper. In the first half of the paper, the control systems for enhancing vehicle dynamics are described. The active front steering by using steer-by-wire mechanism for improving vehicle handling and stability is mainly presented. The latter half of the paper presents the control system designed for driving assist system. The lane keeping control with torque distribution strategy is described. The theoretical controller design and experimental validation are shown in the paper

Theory, algorithms and technology in the design of control systems

Control theory deals with disciplines and methods leading to an automatic decision process in order to improve the performance of a control system. The evolution of control engineering is closely related to the evolution of the technology of sensors and actuators, and to the theoretical controller design methods and numerical techniques to be applied in real-time computing. New control disciplines, new development in the technologies will fertilize quite new control application fields. The status report gives an overview of the current key problems in control theory and design, evaluates the recent major accomplishments and forecasts some new areas. Challenges for future theoretical work are modelling, analysis and design of systems in quite new applications fields. New effective real-time optimal algorithms are needed for 2D and 3D pattern recognition. Design of very large distributed systems has presented a new challenge to control theory including robust control. Control over the networks becomes an important application area. Virtual reality is developing in impressive rate arising new theoretical problems. Distributed hybrid control systems involving extremely large number of interacting control loops, coordinating large number of autonomous agents, handling very large model uncertainties will be in the center of future research. New achievements in bioinformatics will result in new applications. All these challenges need development of new theories, analysis and design methods.

THEORY, ALGORITHMS AND TECHNOLOGY IN THE DESIGN OF CONTROL SYSTEMS: “Status report prepared by the IFAC Coordinating committee on Design Methods”

Control theory deals with disciplines and methods leading to an automatic decision process in order to improve the performance of a control system. The evolution of control engineering is closely related to the evolution of the technology of sensors and actuators and to the theoretical controller design methods and numerical techniques to be applied in real time computing. New control disciplines, new development in the technologies will fertilize quite new control application fields. The status report gives an overview of the current key problems in control theory and design, evaluates the recent major accomplishments and forecasts some new areas. Challenges for future theoretical work are modelling, analysis and design of systems in quite new applications fields. New effective real-time optimal algorithms are needed for 2D and 3D pattern recognition. Design of very large distributed systems has presented a new challenge to control theory including robust control. Control over the networks becomes an important application area. Virtual reality is developing in impressive rate arising new theoretical problems. Distributed hybrid control systems involving extremely large number of interacting control loops, coordinating large number of autonomous agents, handling very large model uncertainties will be in the center of future research. New achievements in bioinformatics will result in new applications. All these challenges need development of new theories, analysis and design methods.

Attaining optimal controls for manipulating quantum systems

AbstractThis article reviews the procedures for attaining laser optimal control fields to manipulate the dynamics of quantum systems. Optimal control theory, whether implemented as a computational technique or directly in the laboratory, is the most general means to achieve precise control of quantum systems. In the case of theoretical control design, a class of monotonically convergent iteration algorithms are presented, which can reduce the computational effort involved. Implementation of optimal control field design can provide physical insight into the feasibility and mechanism of control, even for quantum systems whose Hamiltonian might contain some degree of uncertainty. Moreover, optimal quantum control fields may be directly determined in the laboratory by an analogous procedure with the molecule subject to manipulation acting as an analog computer to guide the discovery of successful controls. To facilitate this process closed‐loop iteration is set up with the loop consisting of the laser, the molecular sample, and a learning algorithm to recognize patterns in the control fields giving rise to successful experimental outcomes. Theoretical design and laboratory learning can act in tandem with each other to achieve the best control and reveal information on how the control process occurs. © 2003 Wiley Periodicals, Inc. Int J Quantum Chem, 2003