Applied Mechanics and Materials Vols. 241-244

Abstract: Displacement and vibration can always be found during the applications of CFRP ( carbon fibe reforced polymer). So it’s quite meaningful to measure the displacement of CFRP directly. Eddy current sensor is a promising tool for this measurement. CFRP presents great heterogeneity and high anisotropy in electromagnetic properties. At the same time, it has been proved that CFRP has quite weak conductivity. All of these means great challenge to the use of eddy current sensor, as the sensitivity would be much lower compared with traditional material such as aluminum. Many experiments have been carried out on the experimental platform self-developed in laboratory. A simplified eddy current sensor with adjustable resonant circuits was designed. Two different kinds of CFRP were used as specimens. For purposes of comparison, an aluminum ingot sample was also tested. A number of experimental data and results have been achieved. It is shown that the sensitivity will be highly improved by adjusting the divider resistance and the actuation frequency.

Abstract: Before final assembly and while debugging a missile, in order to ensure the flight control system can work stably and reliably, it is necessary to develop an auto test system for a general performance test, including electrical performance, inertial measurement device and navigation accuracy. After describing the composition and working principle of the flight control system, summarizing the test requirements, this paper puts forward to a test plan based on a industrial computer, introduces the hardware design and hardware anti-jamming techniques in detail. The test system with self-test function has been applied in testing the flight control system generally and reliably.

Abstract: Radio amendatory channel is used in command guidance for missile, whose working state has direct influence on the precision of a missile. Therefore, it’s necessary to design a radio frequency detector for cycle detection of radio amendatory channel. After analyzing operating principle of the radio amendatory channel, the paper proposes a detecting program, introduces hardware and software design of radio frequency detector including high frequency receiving module, intermediate frequency receiving module and information processing module. The radio frequency detector has been applied in detecting airborne radio amendatory channel successfully improving support efficiency, and provides a reference for detecting other radio frequency.

Abstract: With a higher level of the information techonology application in weapon system, the comprehensive electric system becomes more and more complicated, bringing about higher requirements on equipment support. In this paper, the research is mainly targeted at the integrated electrical system for a certain air defense weapon system. The offline live testing plan is employed, and simulated field simulation technology, switch topology in different forms are intergrated throughout the research to complete the performance testing on the major electrical equipment, so as to test the equipment integrity. Research and development of the testing system provide a feasible design method and means of implementation for the performance testing and trouble diagonosis for electrical equipment of the new equipment.

Abstract: This paper discusses the design of moisture testing system for ultra-dry granular material. It designs from software and hardware aspects in detail. In hardware design, humidity sensor of HM1520 and data acquisition board of PXI-6070E are used; signal conversion between voltage and humidity is based on sensor circuit; PC is used to manage data acquisition and analysis. In software design, programming is based on LabVIEW2011, it included five models such as DAQ, alarm value judgment, data saving, data querying, data printing etc. In system, the data acquisition is based on PXI bus. It is easy to operate data because of using the access database and LabSQL. The system has the following advantages: graphical editing language improving the programming speed, its interface is friendly for users to understand and operate because of visual interface.

Abstract: According to the characteristics of the NVD optical head spot, designing the Virtual instrument testing system based on NI Image processor, denoising the optical head spot, extraction the spot target, calculation of the spot parameter. The spot definition will be better and have good performance after the software processing. The detection method has such advantages as easy to integrate the function of computer hardware and software, highly cost-effective, good reliability, certain versatility and expanding. It has the certain reference value on the similar characteristics study of optical-mechanical-electric system and project evaluation.

Abstract: Analyzed the main factors affecting machining precision of three jaw self-centring chuck with plane thread. Reviewed the states of detection about the error of three-jaw chuck with plane thread. For the shortcomings of the detection in accuracy and efficiency, proposed development trends of using coordinate measuring machine, based on the secondary development of the software to adapt to the fast and batch detection about the error of different specifications of chucks with plane thread, which has a guiding significance to enhance the error detection level of the plane thread and to ensure its precision.

Abstract: A gas flowmeter with temperature compensation is designed based on the single assembled hot-film probe. Experiments are carried out to analyze the temperature characteristics of the hot-film probe. The performance of the automatic temperature compensation units is studied. The flowmeter is tested on the Sonic Nozzle standard flowrate system for the calibration of flowmeters. The experimental results show that the precision is up to 0.6% and the ratio of the measurement range can be 60:1.

Abstract: Potentially low cost and large-area polycrystalline mercuric iodide (α-HgI2) is one of the preferred materials for the fabrication of room temperature X-ray and gamma-ray detectors. In this paper, polycrystalline α-HgI2 films have been grown through combining vertical deposition method with hot wall vapor phase deposition (HWPVD) method. X-ray diffraction (XRD), scan electron microscopes (SEM) and Raman spectrum were used to characterization the HgI2 films obtained, and I-V characteristics was also tested. Using the polycrystalline α-HgI2 films, we get the detector. According to the detector, on the one hand, a dark current test is made by using KEITHL EY 485 picoammeter; on the other hand, the Agilent 4294A precision impedance analyzer is taken to test the characteristic curve of its capacitor frequency.