Advanced Materials Research Vols. 383-390

Abstract: According to the developmental trend of modern automobile instrument, this paper puts forward a multifunctional digital instrument based on the embedded Linux system. The digital instrument panel consists of embedded microprocessor and contact screen, and it could not only receive and process all kinds of driving information from peripheral interface and display the results on the LCD, but also has the function of aided parking. This paper proposes an integrated design solution for the digital instrument. The design selects the TI’s TMS320DM355, which includes LCD and contact screen module, CAN bus module, LIN bus module, video-in and audio-out. The digital instrument can receive real-time data, and also process the data and store it in the RAM and display all vehicle operating parameters in the LCD and realizes real time monitoring in backing up. Based on the experiment, it is proved that the designed system reaches the primary design specifications.

Abstract: A new method of detection of coding signals under the background of sea clutter is presented. The process of signal detection consists of three stages: modeling sea clutter signals based on chaos, one-step ahead prediction of chaotic signals and detection decision making. In this method, models of chaotic signals were created in the form of multi-layer perceptron neural networks, coded signals take on 13-element Barker code. The experiment results show detection of coding signal by using this method has higher detection probability and lower false alarm probability and good performance of the whole detection although with a low SNR. This method turned out to be very robust to different chaotic signals.

Abstract: The doubly salient electro-magnetic motor (DSEM) suffers from significant torque ripples when operating in the conventional angle control method. To weaken the effects of the torque ripples, the ripple generation mechanism is first analyzed in this paper. Then, the operation principle and steady state of the split-capacitor in DC-link of the half-bridge converter are discussed in detail, thus an optimized control strategy of the half-bridge converter is proposed for the DSEM drives. The simulation and experimental results verify that the optimized angle control strategy can alleviate the torque ripples effectively and improve the motor performance.

Abstract: The main steam Pressure is one of the most important guidelines on Circulating Fluidized Bed Boiler (CFBB) operation quality and an important part in control system of CFBB. However, It is very difficult to establish the exact mathematical models of controlled objects because the combustion system of circulating fluidized bed boiler is an object that has many features: distributed parameters, nonlinear, time-varying and long time-delaying. it is unfavorable to control it with traditional controller. Therefore , In this paper fuzzy controller is used in controlling main vapor pressure systems of CFBB, and the fuzzy cascade control system is designed. In computer simulation, the fuzzy cascade control system exert stably, and has perfect control effect to main vapor pressure systems of CFBB.

Abstract: The application of plastic gear is becoming more and more widespread due to its advantages of low noise, shock and vibration absorption and self-lubrication. Friction heat of plastic gear is an important reason for their failure, because the thermal conductivity of plastic is smaller than the metal and the heat generated by friction is an important factor for temperature rising of plastic gear. This paper established a tribology and temperature model of plastic gear transmission by the way of theoretical analysis and finite element simulation of plastic and steel helical gear transmission. The result of finite element analysis shows that friction heat of plastic gears generated during meshing is comparatively large, but the friction of plastic gear and steel gear during the process of meshing is small. The analysis conclusion, contrapose the tribological properties between plastic and steel helical gear, enriched and improved the research in this field and provided some ready-made experiences.

Abstract: This paper analyzes reasons for non-synchronization of double cylinders of segment erector of TBM and puts forward feasible synchronized control proposal. Meanwhile, mathematical modeling is built and AMEsim software is used for simulation of synchronized and coordinated control of lifting system of segment erector. The simulation results show that synchronized control accuracy meeting the design requirements.TBM (tunnel boring machine) is a large-sized hydromechatronics engineering device in modern tunnel works, and segment erector is its key component. Research on double cylinders of hydraulic system of segment erector of TBM is carried out in this paper, and AMEsim software is used to simulate the synchronized and coordinated control of lifting system of segment erector.

Abstract: Although large effort has been done during earth-rock filled dam construction, the artificial-based management is hard to fulfill the need of large-scale mechanized construction. With transportation monitoring system, earth move vehicles can be overall monitored. Through analytical calculation, state parameter of each controlling unit of transportation system can be obtained. On the other side, simulating model is built and calculating program is written based on the specific analysis to transportation system. When the site condition changes during construction, simulating parameters are seated and simulating calculation is done. According to the results, sensitivity analysis is done to different machinery allocation schemes. Then, combined with the site condition, best scheme can be chosen and real-time scheduling of machineries can be realized. The result is applied in the construction of Nuozhadu hydropower station project, providing scientific basis for the optimal scheduling of field machinery allocation.

Abstract: In this paper, the reason of axial magnetized TPMLSM salient pole force has been discussed, as well as its calculation formula. Calculate force with the virtual work principle. Then the relation between the maximum with average of the force and its phasic forward angel, has been explained, as well as the function of salient pole force and its location. Furthermore, a kind of method notching iron magnet poles to decrease axial magnetized salient pole force has been introduced, and the influence impressed on the force by notching has been analyzed qualitatively. Obtained field distribution by finite element method slotted magnetic. Compared the salient force of different number slotted iron pole. In the end, finite element method has been utilized to testify the availability of this way to decrease salient pole force.

Abstract: Aiming at the complexity of mechanical devices and the polytrope of operating conditions for marine propulsion plant, the modeling and simulation of propeller and dull system are investigated based on MATLAB/Simulink. The simulation model of propeller and dull system is constructed in which the Chebyshev fit expression across four quadrants is given for the propeller. So it becomes practical to express static and dynamic properties of propeller and dull system. A luxury cruises fitted on two engines and two fixed pitch propellers is considered to perform simulation tests. The actual navigation conditions of marine propulsion plant, including starting, parking and reversing etc, are taken into account. The simulation results analysis illustrates the correctness and validity of modeling and simulation for propeller and dull system. Thus provides a new method for the optimization and design of marine propulsion plant.

Abstract: In order to achieve high position precision and synchronization between the wafer stage and the reticle stage, a cross-coupled sliding mode control scheme for a coarse-fine combined synchronization servo system of lithography is proposed. To accomplish high bandwidth and high tracking precision, a conventional linear motor is combined with a voice coil motor as a coarse-fine dual-stage control system. A cross-coupled structure is presented to decrease the synchronization error during scanning operation. Sliding mode control law is designed based on the control error and the synchronization error. Simulation results show that the synchronization error and the control error have the same order of magnitude, and the dynamic performance of the control system satisfies the design requirement.