Applied Mechanics and Materials Vols. 416-417

Abstract: the development of numerical control technology changes with each new day, the article expounds the nc machine tools with complex shape parts of high precision requirements for rapid development, widely used in conventional parts processing, complex shape parts processing. Nc machine tools with the aid of microelectronics and computer technology rapid progress, is toward high precision, multi-function, high speed, high efficiency, composite processing functions, such as intelligent direction, our country numerical control system in the technology has already become more and more mature, in the major key technologies, has reached the foreign advanced level.

Abstract: A common source of noise is operational excitations of mechanical devices, which cause vibrations and thus sound radiation from their surfaces. Plate and shell structures in transformer, vehicle or airplane applications vibrating in resonance show particularly high noise levels. Classic methods of noise reduction such as passive damping or anti-noise are not efficient enough in certain cases. Therefore, the use of structural control for reduction of sound radiation is presented in this paper. A piezoelectric ceramic actuator (PCA) for the active noise control is also proposed. The structure of the proposed PCA is discussed and the control method of the structure is carried out. The proposed PCA has excellent performance compared with conventional ones, such as more force, convenient installation and disassembly. The active noise control (ANC) system and control algorithm are also discussed in this paper. The performance of the proposed controller is analyzed through simulation in the Matlab/Simulink.

Abstract: The paper proposed program of lower-cost traditional 8-bit micro-controller with Web servers function, and is designed for remote control system. The system has the flexibility and low cost. And according to the actual needs of the decision-making and management of plant irrigation, intelligent irrigation system was designed and implemented.The system solve the difficult and critical hardware products import prices too high and difficult to promote for distribution of soil temperature and humidity monitoring.The system cost compared to similar foreign products decreased 44.8%.Compared with traditional irrigation methods, crop water use efficiency of 22.6%.The design of software and thinking can popularize and promote practical reference value, the future of smart home system.

Abstract: The co-simulation method of one large electro-hydraulic servo system based on software interface is proposed in this paper. The rigid-flexible-coupling dynamic model of the electro-hydraulic servo mechanism was built through data exchange of SolidWorks, ANSYS and ADAMS, the hydraulic system model and control system framework was built by EASY5 environment, the controller was built by Simulink. The integration of simulation models for the large electro-hydraulic servo system was realized by software interfaces. In view of the poor operation conditions, the high requirement of control precision and real-time characteristics, adaptive fuzzy sliding mode control strategy was applied to position tracking control of the servo system. Simulation results verified the effectiveness of this method.

Abstract: Reasonable deployment and effective control can help the distributed jammers to function better. According to the counter-jamming theory of PAR, a new method is presented to deploy the distributed jammers which can provide the azimuth and distance of each jammer to enhance its jamming effects. After the jammers are located, computers are adopted to control the distributed jammers which should be turned on/off properly for suitable duration. The target detection probability under jamming condition is selected to evaluate the jamming effects, and the experiment results show that this method has steady jamming effects against PAR.

Abstract: In this paper, a simple yet robust closed-loop identification method based on step response is presented. By approximating the process response firstly using Laguerre series expansions, a high-order process transfer function can be obtained. Then, a linear two-step reduction technique is used to reduce the high-order process to a second-order plus time delay model based on the frequency response data. This method is robust to measurement noise and it also does not need any numerical technique or iterative optimization. Simulation examples show the effectiveness of the proposed method for different process models. Comparison of identification performance between different methods is also illustrated in this work.

Abstract: DCS (Distributed Control System) as a mature technology plays a dominant role in industrial control field. This thesis makes an introduction to the development and main characteristics of DCS system, which makes an elaboration of the structure and features of JX-300X system provided by SUPCON and explains its implementation process in 10000 air separation unit of a certain steel mill.

Abstract: For the demand of helicopter test, a helicopter manipulating control system was designed and implemented. This paper describes the structure and principle of hardware, the underlying and PC control program, and establishes the mathematical model between control angles and displacement of actuators. According to the practical application, the system meets the requirement of helicopter test very well.

Abstract: The application of hydraulic drive as well as control technology to construction machinery control as well as operating system has been very common. In this paper, network control system is briefly introduced first, and then the computer controls of vehicle and construction machinery hydraulic system are discussed respectively from the new methods for the motion control and integration of drive and operating system, and the operating and control system design of beam lifting machine DJY200.

Abstract: Network control system (NCS) is developed from the cross-integration of network technology and control technology, which is with advantages of sharing resources, low price, light weight, easy installation and maintenance, low energy consumption and so on. A robust control approach is proposed in this paper to solve the stabilization problem for networked control systems (NCS) with short time-varying delays. By considering state feedback controllers, the closed-loop NCS is described as a discrete-time linear uncertain system model. Then, the asymptotic stability condition for the obtained closed-loop NCS is derived, which establishes the quantitative relation between the stability of the closed-loop NCS and two delay parameters, namely, the allowable delay upper bound (ADB) and the allowable delay variation range (ADVR). Furthermore, design procedures for the stabilizing controllers are also presented. An illustrative example is finally given to demonstrate the effectiveness of the proposed method.