Applied Mechanics and Materials Vols. 635-637

Abstract: Hitachi force motor valve has been widely used in the hydraulic automatic gauge control (AGC) system of rolling mill due to the characteristics of fast response, high control accuracy and strong anti-pollution ability. It is an important part to control the steel production cost by detecting the performance index of the FMV effectively and in real time. Traditional Servo valve test system detects its static characteristics through the flow and pressure changes between the traffic cavity, and this principle can solve the three position four way servo valve performance test. However, FMV is a special three-way valve and it is hard to test its static characteristic curve like three position four way servo valve. This paper proposes a FMV testing method and has realized it. The test platform is designed and built according to the hydraulic valve testing performance index for detecting the performance of a force motor valve. Not only were force motor valve (FMV) performance characteristics tested effectively but also the performance curves were drawn. The results show that the FMV performance testing method we have built can be effectively used to detect the static performance index of FMV.

Abstract: CNC programming is from the part drawings to get the whole process of NC program, the core of the work is to generate tool paths, and then dispersed into the knife sites generated by the NC post-processing program. As one of the key technologies of CNC machining, the preparation of the efficiency and quality of its programs largely determine the processing accuracy and production efficiency. Engineering approach of this research complex part features macro programming design.

Abstract: Rotary flexible manufacturing cell with multi-station automatic stretching is designed in this paper to meet the requirements of the machining process of cylindrical drawing parts as well as the needs of different stations for multi-drawing. The cell uses fixed circular disc worktable with multi-station. Each machining station has hydraulic stretcher to complete the drawing of the workpiece. Flexible manipulator finishes automatic loading and unloading among hydraulic stretchers. Gripper of manipulator with automatic center aligning and size control can grip workpiece in various sizes and has the function of self-centering. This equipment has completely realized all the stretching processes automaticly from feeding sheet metal to sending and forming workpieces. It can improve production efficiency and quality. It can also improve safety, reliability and cost efficiency. When replacing worked parts is needed, simply replace modular mold of every station in fixed circular disc worktable.

Abstract: In order to solve the problem of large amount of calculation and real time is not high in the process of NURBS real-time interpolation feed speed planning, offline feed speed planning method is proposed, the method plan speed in non real-time cycle, and generate the feed speed curve. In order to meet the machine tool dynamics constraint, the maximum acceleration and the jerk constraints were considered fully in the planning process. The simulation analysis show that the proposed method can greatly reduce the amount of computing tasks in real-time interpolation cycle, improve the real-time performance of interpolation; At the same time, the speed curve of the planning satisfies the requirement of machine tool dynamics, has the good effect of feeding speed smooth, is helpful to improve the interpolation precision.

Abstract: User modeling is an important strategy for designing effective user interface. User model for turret is different with general application. This paper concerns on modeling user of turret. Main emphasis is given on the relationships of man, machine and environment. The user models can help determine the characteristics of the turret user and how they affect the design of the adaptive interface. In this paper we present the progress of user model development and give some case studies using the proposed model.

Abstract: Problems of power quality have been increasingly concerned by the researchers, as the domestic appliances we are usually used are single-phase load, which mainly causes the unbalance of three-phase voltage of power supply. If the induction motor is supplied by three-phase unbalanced voltage, the currents, active and reactive power, efficiency, and losses are affected as the negative-sequence current appears, this paper is emphasized on the induction motor’s characteristics when its’ power supply is three-phase unbalanced voltage by experimental research.

Abstract: In order to guarantee the high and stable yields, improve the economic benefits and promote the transplanting technology of corn. The pitch curve of non-circular gear is fitted based on quasi uniform B-spline theory, corn full-automatic transplanting mechanism has been invented, and its kinematics mathematical model has been built through analysis of transplanting mechanism. The computer aided analytical and optimized software has been developed on software Matlab’s platform. Through tuning the data points by man-machine interaction, pitch curve of non-circular gear and structural parameters are optimized, until track and attitude of mechanism meet the demands for corn transplanting process. The 3 actions of taking, transportation and planting corn transplantation can be achieved orderly by a mechanism.

Abstract: Considering the issue that it is difficult to precisely extract the rotor information within the full scope of speed for PMLSM sensorless driving system,this paper proposes a convenient position estimation algorithm based on a new type of closed-loop observer to adapt the characteristics of wide range of linear motor speed variation.To accurately estimate the rotor position information for PMLSM system with speed varying from launching to full speed,the new algorithm is like following: based on the three-phase stationary coordinate system of PMLSM voltage model, deduce quadrature-axis current differential equations from its rotating coordinate system(d-q axis)voltage model through by Parker transformed. moreover,get the actual alternating axis current by current measuring circuit. By driving a closed-loop observer through difference between the two current differential to input and process the difference of magnetic polo position by PI algorithm, then estimate the position of the motor.Simulation results show that the convenient algorithm with position closed-loop observer can estimate the location of the motor relatively accurately in full range of speed.

Abstract: A unified control method of comprehensive compensation system based on CS- APF and SVC is introduced in this paper. SVC is composed of thyristor controlled reactor (TCR) and fixed capacitor (FC). For the CS- APF control, a feedforward control for harmonic compensation of SVC and load is applied. The CS- APF is enabled to optimize the var compensation performance of SVC. Finally, the simulation results show that the system can effectively compensate reactive power and eliminate harmonic currents.

Abstract: It uses different control algorithms in resistance furnace temperature control temperature will produce different results.The pros and cons of control algorithm affects the precision of temperature control.Temperature is a nonlinear time-varying parameters and it susceptible to interference with a strong randomness.Conventional PID is not easy to achieve the precise control of temperature.We adopt advanced graphical programming software LabVIEW to the resistance furnace temperature control with the fuzzy.We design the fuzzy controller about temperature and make a lot of test independently. Finally,We achieved good effect of temperature control.