Efficient Application of Automation Technology in Thickener Process

2015 ◽  
Vol 1094 ◽  
pp. 441-444
Author(s):  
Dan Dan Xie ◽  
Xiong Tong ◽  
Xian Xie ◽  
Kai Hou ◽  
Ji Yong Li

The text mainly introduced the thickener’s front technology and also talked about the process of using flocculent addition and the emissions of underflow density presenting a more optimal automatic control scheme on the basis of the original automatic project. Using automatic control components like PLC programmable logic controller and the control elements of the inverter make the thickener in a whole closed-loop system for the flocculant addition and the density of the ore and the process of discharge. It will bring a positive side for our economic, social and ecological environment.

2015 ◽  
Vol 2015 ◽  
pp. 1-11 ◽  
Author(s):  
Jinsheng Xing ◽  
Naizheng Shi

This paper proposes a stable adaptive fuzzy control scheme for a class of nonlinear systems with multiple inputs. The multiple inputs T-S fuzzy bilinear model is established to represent the unknown complex systems. A parallel distributed compensation (PDC) method is utilized to design the fuzzy controller without considering the error due to fuzzy modelling and the sufficient conditions of the closed-loop system stability with respect to decay rateαare derived by linear matrix inequalities (LMIs). Then the errors caused by fuzzy modelling are considered and the method of adaptive control is used to reduce the effect of the modelling errors, and dynamic performance of the closed-loop system is improved. By Lyapunov stability criterion, the resulting closed-loop system is proved to be asymptotically stable. The main contribution is to deal with the differences between the T-S fuzzy bilinear model and the real system; a global asymptotically stable adaptive control scheme is presented for real complex systems. Finally, illustrative examples are provided to demonstrate the effectiveness of the results proposed in this paper.


2018 ◽  
Vol 41 (5) ◽  
pp. 1266-1277 ◽  
Author(s):  
Kun Yan ◽  
Mou Chen ◽  
Qiangxian Wu ◽  
Ke Lu

In this paper, an adaptive robust fault-tolerant control scheme is developed for attitude tracking control of a medium-scale unmanned autonomous helicopter with rotor flapping dynamics, external unknown disturbances and actuator faults. For the convenience of control design, the actuator dynamics with respect to the tail rotor are introduced. The adaptive fault observer and robust item are employed to observe the actuator faults and eliminate the effect of external disturbances, respectively. A backstepping-based robust fault-tolerant control scheme is designed with the aim of obtaining satisfactory tracking performance and closed-loop system stability is proved via Lyapunov analysis, which guarantees the convergence of all closed-loop system signals. Simulation results are given to show the effectiveness of the proposed control method.


Author(s):  
Lawrence J. Prinzel ◽  
Mark W. Scerbo ◽  
Frederick G. Freeman ◽  
Peter J. Mikulka

A bio-cybernetic, closed-loop system was validated for use in an adaptive automation environment. Subjects were asked to perform either a single task or multiple tasks from the Multi-Attribute Task Battery. EEG was continuously sampled while they performed the task(s) and an EEG index was derived (20 Beta/Alpha + Theta). The system switched between manual and automatic modes according to the level of operator engagement based upon the EEG index. The NASA-TLX was administered after each trial. The results of the study demonstrated that it was possible to moderate an operator's level of engagement through a closed-loop system driven by the operator's EEG. In addition, the system was sensitive to increases in task load. These findings show promise for designing adaptive automation technology around psychophysiological input.


1998 ◽  
Vol 120 (3) ◽  
pp. 814-821
Author(s):  
H. M. Sardar ◽  
M. Ahmadian

The validity of the claim by many studies that the damping and stiffness forces can be ignored when designing a model reference adaptive controller, is examined. For a simple plant, the sensitivity of the closed loop system to the inertial, damping, and stiffness nonlinearities are investigated, through a simulation analysis. It is shown that the closed loop system is sensitive to the changes in the inertial nonlinearities, and relatively insensitive to variations in the damping and stiffness forces. This supports the assumption made in many previous studies.


2005 ◽  
Vol 128 (2) ◽  
pp. 414-421 ◽  
Author(s):  
A. Ibeas ◽  
M. de la Sen

A multiestimation-based robust adaptive controller is designed for robotic manipulators. The control scheme is composed of a set of estimation algorithms running in parallel along with a supervisory index proposed with the aim of evaluating the identification performance of each one. Then, a higher-order level supervision algorithm decides in real time the estimator that will parametrize the adaptive controller at each time instant according to the values of the above supervisory indexes. There exists a minimum residence time between switches in such a way that the closed-loop system stability is guaranteed. It is verified through simulations that multiestimation-based schemes can improve the transient response of adaptive systems as well as the closed-loop behavior when a sudden change in the parameters or in the reference input occurs by appropriate switching between the various estimation schemes running in parallel. The closed-loop system is proved to be robustly stable under the influence of uncertainties due to a poor modeling of the robotic manipulator. Finally, the usefulness of the proposed scheme is highlighted by some simulation examples.


2005 ◽  
Vol 2005 (2) ◽  
pp. 195-214 ◽  
Author(s):  
Mohamed Zribi ◽  
Muthana T. Alrifai

This paper investigates the control problem of variable reluctance motors (VRMs). VRMs are highly nonlinear motors; a model that takes magnetic saturation into account is adopted in this work. Two robust control schemes are developed for the speed control of a variable reluctance motor. The first control scheme guarantees the uniform ultimate boundedness of the closed loop system. The second control scheme guarantees the exponential stability of the closed loop system. Simulation results of the proposed controllers are presented to illustrate the theoretical developments. The simulations indicate that the proposed controllers work well, and they are robust to changes in the parameters of the motor and to changes in the load.


2000 ◽  
Author(s):  
Perry Y. Li ◽  
Dongjun Lee

Abstract A control scheme for linear dynamically similar bilateral teleoperated manipulator system which ensures that the closed loop system is energetically passive is proposed. Energetic passivity implies that the teleoperated manipulator system is safe to interact with, and that the coupling between the system and any strictly passive environment is stable. The control objective is for the two manipulators in the system to behave in unison under the influence of both the operator and the work environment, while maintaining energetic passivity. The dynamics of the system in unison and its response to the operator and work environment can be specified as kinematic and power scalings. To maintain energetic passivity with feedback and feedforward actions, the proposed control makes use of two fictitious internal energy storages. The result is that when the internal state of the storage elements are suitably initialized, the teleoperated manipulator system achieves asymptotic locking even in the presence of external (bounded) forcing from the operator and work environment.


Author(s):  
Hui Chen ◽  
Manu Pallapa ◽  
Weijie Sun ◽  
Zhendong Sun ◽  
John T. W. Yeow

This paper presents a sliding mode control scheme to improve the positioning performance of a 2-Degree-of-freedom (DOF) torsional MEMS micromirror with sidewall electrodes. The stability of closed-loop system is proved by Lyapunov stability theorem under the existence of bounded parameter uncertainties and external disturbances. Furthermore, the performance of the closed-loop system is illustrated by experimental and simulation results which verify that the feasibility and effectiveness of the proposed scheme. The results demonstrated that the torsional MEMS micromirror with the proposed sliding mode controller has a good transient response and tracking performance.


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