Papers by Keyword: Feedback Control

Abstract: Feedback and process control of metalforming processes has received increasing attention the lastdecade. Basically there exist four control philosophies; control ofprocess parameters during the punch stroke, iterative learning control(based on historical data), a combination iterative learning andfeedback control and finally feed-forward control. The present work willpresent three different control schemes which all are based onfeedback philosophy i.e. control during the punch stroke or iterativelearning control, where process parameters are updated according toprocess history. The three control schemes are tested using a non-linear finite element model of a square deep-drawing and finallypros and cons are discussed based on the numerical results.

Abstract: In this paper, the ablated microstructures on copper film affected by ultraviolet nanosecond pulse laser are presented. The experimental system was consisted of two lasers, optics and controlling electronics. A 3000mW, 355nm Q-switched ultraviolet lasers was used to the micro-polishing experiments in the work. The repetition rate of the ultraviolet pulse laser is from single-shot to 100kHz, and the pulse width is less than 40ns. The sample used in experiment is copper film (200 nm) sputtered on glass. A series of experiments at different laser parameters and speed of work platform are done. The ablating experiments are also carried out on focusing and defocusing application in the laser direct writer. The results were analyzed.

Abstract: This paper introduces an alignment method using machine vision feedback control method. A panel is placed on a XXY table and its posture is inspected by image sensors with a frame grabber. The alignment of the panel is corrected by adjusting its positions until the amount of misalignment converges into a small tolerance error. Two-phase control process is also derived with this image acquisition design. Applying this proposed control method, long distance moving requirement and better alignment precision performance request can be also guaranteed. Experimental results are shown to demonstrate the feasibility of this alignment control system.

Abstract: Synchronization of a class of time-delay chaotic systems with parameters perturbation is discussed in this paper. The knowledge of the delay time is unknown. Firstly, we design a newresponse chaotic system , then based on Lyapunov-Krasovskii function, we show that the responsechaotic system can synchronize the driven system. The proposed method is tested and verified byan numerical example.

Abstract: Based on the pioneer work of Konishi et al, an improved coupled-map car-following model is proposed by considering the effect of information about two preceding vehicles to the considered one. The stable conditions under which the traffic jam can be suppressed are analyzed by applying control theory. The results are compared with that of Konishi et al. The simulation results show that the new model with the control strategy could suppress the traffic jam more effectively.

Abstract: This paper propose fractional-order Lu complex system. Moreover, projective synchronization control of the fractional-order hyper-chaotic complex Lu system is studied based on feedback technique and the stability theorem of fractional-order systems, the scheme of anti-synchronization for the fractional-order hyper-chaotic complex Lu system is presented. Numerical simulations on examples are presented to show the effectiveness of the proposed control strategy.

Abstract: The overhung spindle system is studied as the object after remanufacturing, the spindle simplified cantilever and the mathematical model was established based on the simplified equivalent device. The simulation analysis of the dual cantilever was carried out by using ANSYS.The vibration mode and inherent frequency of the cantilever, the deformation caused by the applied loads was given in this paper.It is designed by the linear quadratic optimal control of two state regulator through analyzing the vibration form and loading condition,use of independent modal control algorithm based on the detection of the position feedback control,It is inhibited effectively when a cantilever beam subjected to external transient pulse disturbance caused by two order and higher order system mode vibration,and using the Matlab software programming for active vibration control effects simulation.In addition.Matlab software gave the image result of response of vibration system.Both the brief solution program and the accurate image data which corresponded with vibration theory showed the feasibility and superiority during solving these responses of the spindle vibration system after remanufacturing.Thereby,this research provided an easy and effective method to solve the response of general mechanical vibration system.

Abstract: With the progress of photovoltaic technology and sensor, this paper propose a new automatic feedback control system which based on the color sensor TCS230 and LED flexible lighting equipment to detect and treat infantile jaundice. By testing the severity of the yellowing baby skin, the system makes any response, such as the lights’ intensity and working time. And the final aim is to realize the detection and treatment synchronously for infantile jaundice, promoting the development of intelligent medical treatment.

Abstract: In this study, a hydraulic servo system for mold oscillating mechanism was investigated. In order to check the efficiency and the stability of system, its geometrical designs, which change the natural characteristic of system, including a spool volume, area of piston, and so on were analyzed by a non-linear model. The model was composed of the equation of orifice, the continuity equation, and the force equilibrium including a variable effective bulk modulus belonging to operating oil, gas, and cylinder. All simulations were conducted by the MATLAB SIMULINK, and simulated as specific conditions corresponding real operation conditions in the steel industry. According to the analysis, the relation between a controller, servo design, and system performance was investigated with physical means. And, the fact that not compared to other design variables, the entrance shape on spool was dominant to determine the stability and the performance of system, was found. Furthermore, a fault detection method, and optimization problem including this work were discussed.

Abstract: Although class D amplifier has the merits of high efficiency, a little heat and small Bulk, its distortion is larger than linear counterparts due to switching behaviour of power transistors. Its principle and several new pivotal control technologies were presented in this paper. In this way, efficiency of 90% can be achieved and the degree of the distortion can be less than 0.4%.