Abstract:The structure, operational principle of several typical liquid density sensors and their application features are described and analyzed.

Abstract:In this paper,a four-parameter least square sine wave curve-fit method based on the frequency estimation method and realized by using the three-parameter sine wave curve-fit method is introduced.The features of it are: 1)absolute convergence;2)without the pre-estimation of parameters;3)simple and easy to be realized;4)no iteration;5)high speed calculation course.The simulation results have proved the correctness,rightness and the defect of this method.

Abstract:Pointing to the data obtained from semi physical simulation of certain helicopter which mainly has low-frequency noise, a data processing method of depressing and filtering noise from the signal, using the pagoda-structure re constructing arithmetic and the wavelet transform principle, is proposed. The result of simulation shows that the method is practical and efficient on off-line dataprocessing.

Abstract:计算了光谱在3～5 μm及8～12 μm范围内,加装与机身结构一体化红外抑制器的某型直升机排气系统的红外辐射特性.计算中考虑了排气系统部分蒙皮的红外辐射、双喷管发动机喷气流的红外辐射、背景辐射及大气的吸收衰减对直升机排气系统红外辐射信号的影响.实验发现,一架加装与机身结构一体化红外抑制器的直升机排气系统红外辐射特性的计算结果,与实测结果基本一致.

Abstract:An independently integrated navigation system using odometer(OD) to assist the strapdown inertial navigation system(SINS/OD) is discussed.In this paper,the OD error equations are proposed in detail.The observed quantity of the SINS/OD is the velocity's differences between SINS and OD,and the SINS/OD also adopts a closed kalman filter to estimate and correct the errors.The results of simulation indicate that the SINS/OD can effectively eliminate the following errors of navigation parameters:attitude,velocity,latitude and longitude etc.

Abstract:Imitating the structure and shape of compound eye of insects,a bionic compound eye measurement system is designed.It is similar to the smallest cell of compound eye and composed of 7 CCD cameras.Several DSP processors are used to process 7 video signals synchronously to simulate the functions of compound eye.Comparing with the traditional vision measuring system,the bionic compound eye system designed has larger view and higher motion sensitivity.The improved relativity method is used to joint the video images to make a panoramic image.It has advantage of eliminating artificial connecting mark preferably caused by differences in local image coordinate and gray level.

Abstract:The position error of BeiDou navigation positioning system, using the three geostationary satellites positioning system and pseudolite technology, is analysed and simulated. Through simulation and analysis, the three geostationary satellites positioning system solves the defect of the original system. But the positioning accuracy exists still. The satellite technology not only solves the defect of the original system but also creates the positioning accuracy.

Abstract:A algorithm for using the minimum zone to evaluate the space linearity error based on the principle of coordinate transformation is introduced, and the mathematical model and calculation example are given in this paper.

Abstract:A kind of ultrasonic telemeter based on AT89C205 is introduced. This telemeter is provided with some merits such as low cost and high-accuracy because of the ultrasonic wave characteristic. The hardware principle electric circuit and the main software design idea are showed. The simulation of the main part of the hardware has been done with Pspice. At last, according to the theoretical analysis and the experience some improvements of the design are made. The system has achieved the anticipated effect.

Abstract:This paper introduces the development of fiber-optic Maeh-Zehnder interferometer during measuring linewidth parameter of single-frequency lasers, and the experiment result has been given.

Abstract:In this paper, an aeronautic test AC power supply based on DSP is proposed. The AC power supply is able to produce the sine voltage, and its frequency and breadth value can be adjusted when the aero AC electro-equipments Work on different status. Furthermore, the seasonal aberrational voltage is produced. The power supply adopts D/A mixed control and repetitive control. The digital part realizes the high precise waveform generator and the control based on voltage virtual value. The analog part adopts the control based on current virtual value and improves the response speed. The test waveform is presented at the end of this paper.

Abstract:A high precision CMOS bandgap reference(BGR)voltage sourcce is described in this paper.With cascode current mirror and self-bias technique,through inverse feedback of OPAMP,it achieves current I_(PTAT) with positive temperature coefficient and current I_(CTAT) with negtive temperature coefficient respectively.Through current's subtraction,two different compensation current can be achieved in the whole temperature range,and then it can accomplish the piecewise compensation for the BGR.Therefore,we get the bandgap reference voltage with very small temperature coefficient.

Abstract:This paper presents a project of sine signal distortion measurement based on PXI bus. The project applies high accurate data acquisition device to acquire data and the curve fitting based on the genetic algorithm to process data acquired. Experiment indicates that the project possesses of high accuracy, good expansibility and high application value.

Abstract:One type of helicopter rotor shaft is the key fatigue part that drives rotor to revolve. This paper principally introduces the testing method of the type of helicopter rotor shaft loading, including the choice of strain gauge, deploying of measuring point ,testing principle, testing result and analysis.

Abstract:介绍了一种新型的刀口扫描法测量可见光CCD的调制传递函数(MTF),首次采用1∶1的无像差光学系统,消除了测量光学系统MTF所带来的较大不确定度分量;采用双刀口方法和动态定焦扫描法,提高了测量效率和精度.

Abstract:A method to measure the water gate flatness is introduced in this paper. This mothod uses the theodolite and vernier. According to field method of minimum containment, the error of the flatness is evaluated. The uncertainty of measurement is also evaluated.

Abstract:According to the development of inertial instrument test platform, this paper presents the necessity of designing inertial instrument automatic test platform. It also introduces the design ideas of the totality of the design of hardware and software of the platform. The test platform has some good advantages such as real time, stability, credibility and being used widely. At the same time, it also provides friendly human-computer interface. This platform makes the whole test process operation convenient, reduces the artificial test error and realizes the automatic operation.

Abstract:Based on the verification regulation of PRT, this paper studies the temperature characteristics of PRT, suggests a method of improving the accuracy of measurement and supplies the uncertainty of calibration point.

Abstract:In this article, a convenient date-fusioning method for the signal of ratate speed is introduced, which is based on the segmented-curvefitting. The precision is improved by using this method.

Abstract:This paper analyses the principle and structure of ground proximity warning computer.Based on it, the test system structure, the software algorithm and the key problem are particularly narrated. The result of practical using indicates that the character of this system is steady, reliable and easy to be operated.

Abstract:A convenient tool to solve the network communication of measurement and control system DataSocket is introduced, and two patterns of development of the network measurement and control system are analyzed. Then based on DataSocket, the design of network testing of the atmosphere data system is discussed.

Abstract:The definitions of the best measurement capability are described in this paper. The evaluation of the expanded uncertainty of electrical energy meters with electronics in the normal calibration is compared with the evaluation of the best measurement capability.