Applied Mechanics and Materials Vols. 40-41

Abstract: There have been more and more types of electromechanical products which is detected and controlled with computer aided techniques, and also they have been more and more automatic. In order to learn and design a system to measure and control electromechanical products quickly, this paper developed a comprehensive test-bed to measure and control parameters. It combines VC++6.0 programming environment, MATLAB and PCL-818HG data acquisition card. This thesis introduced how to examine the displacement, rev, temperature, stress and the scheme of hardware composition to control the rev of engine. It also introduced the multi-threaded programming of VC++6.0 and the development methods of establishing link libraries between MATLAB and PCL-818HG. There were some applications as well.

Abstract: Through analysis and comparison of simple PID control and RBF neural network-PID hybrid control of the pneumatic servo system, then compared the stability and quick response under the two control system. Concluded that RBF neural network-PID hybrid control has better stability and fast response than the simple PID control.

Abstract: The specific guidance simulation system for the infrared air-to-air missile is built. Seeker model including the target detection and tracking loop has simulated not only the different modes of field of view (FOV) according to the geometrical relationship between the target and missile, but also the jamming effect based on the equivalent target calculation; fuze model contains three different trigger mechanisms; guidance of missile is realized via three-dimensional proportional guidance law; the 6 DOF kinematics model and dynamic model of airframe are derived, through aerodynamic force and torque calculating, triple-channel autopilot model is set up by using the PID control method. Finally simulations under three different cases are implemented and the results show that the whole system is credible.

Abstract: This paper addressed the problem of computing practical time-to-go estimation,when constant relative acceleration and measurement distribution were considered . firstly,a time-to-go arithmetic was obtained based on missile and target engagement geometry. The method is a combination of three time-to-go estimate formulations . Then time-to-go estimator was designed by applying the modified gain extended Kalman filter theory.Simulation results show that the proposed estimator can estimate the time-to-go very effectively . The proposed method is simple and straightforward to implement for missiles.

Abstract: In power system, when the overload of large-scale power grid results in serious disaster, the nonlinear dynamic bifurcation is obvious. It will be effective to delay the occurrence of bifurcation through the bifurcation control method, so workers have enough time to take protective measures. We can also design an appropriate controller to prevent these kinds of dangerous disaster effectively. This paper outlines a number of common bifurcation control method, and use one of these method to design a bifurcation controller so as to control the hopf bifurcation in power system and make a Simulation on it.

Abstract: A method to analyze the acoustic signals collected in fully-mechanized caving face is presented in this paper. Through analyzing the marginal spectrum and frequency spectrum of intrinsic mode functions obtained by empirical mode decomposition, acoustic signals’ frequency and amplitude characteristics are gotten, that is, high frequency signals about 1000Hz ~2800Hz are produced when the top coal is combined with gangue. Furthermore, the acoustic signals’ instantaneous energy spectrums in the frequency range of 1000Hz ~2800Hz can be used to identify the coal-rock interface.

Abstract: In order to improve the aquaculture monitoring system in China, this paper designs a system adopting the SIMATIC S7-200 CPU226 and PID control algorithm to make real-time monitoring and controlling for the water level and temperature of closed circulating aquaculture system, thus it can realize constant control of water level and temperature in the culture pond. The overall control scheme and principle of the system are introduced in detail, followed by the structure design of the system software and hardware. The designed system can efficiently achieve system logic control, safety control, fault display and fault treatment.

Abstract: This paper is concerned the problem of robust absolute stabilization of time-varying delay systems with admissible perturbation in terms of integral inequality. A linear state-feedback control law is derived for one class of delay systems with sector restriction based on linear matrix inequality (LMI). Especially, this method does not require input terms are absolutely controllable for nonlinear delay systems. Numerical example is used to demonstrate the validity of the proposed method.

Abstract: This paper analyzes the structure, the physical parameters and the working principle quantitatively of the single-phase DC-turned off High Temperature Superconducting Fault Current Limiter (SFCL) with Saturated Iron Core. On this basis, a dynamic system model is established and simulation to study the relationships among the various system electrical parameters. The simulation results and the actual waveforms collected from the sample machine were compared to verify the correctness of the model. And the simulation experiment shows that this kind of SFCL is available for current limitation.

Abstract: With the development of society, the smoking safety has attracted a wide spread attention. Cigarette draw resistance is an important performance index in tobacco enterprises. The traditional instrument has some disadvantage, such as high cost, slow speed and low precision. Therefore, an automatic sort instrument of cigarette draw resistance is developed, which has self-owned intellectual property. In the instrument, the output of all motors is connected with the mechanical device directly and the TMS320LF2407 chip is used as the controller. The system has been used in a cigarette factory in Shandong province. The result of the experiment shows that the instrument is reliable. In the paper, the control system design is introduced in details.