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Analysis on the influence of random vibration on MEMS gyro precision and error compensation (EI CONFERENCE) 会议论文
2011 3rd International Conference on Mechanical and Electronics Engineering, ICMEE 2011, September 23, 2011 - September 25, 2011, Hefei, China
Hao X.; Li M.; Han X.; Jia H.
收藏  |  浏览/下载：16/0  |  提交时间：2013/03/25
In order to improve its precision in dynamic environment  a Kalman filter was designed. Firstly  two sets of random drift data of MEMS gyro were respectively analysed  and it was found that the variance of random drift under random vibration significantly increased and its mean also changed. Then calculation results show that attitude angle error under random vibration is 2.6  while in the static test it is 0.25. Analysis on the characteristics of random drift was carried out  and it is found that it can be treated as stable  normally distributed random signal. Finally  a corresponding Kalman filter was designed. The results indicated that after filtering the variance of random drift is reduced to 0.0282  26.4% of pre-filtering and the attitude angle error is reduced to 1.5  57.7% of pre-filtering. The above method can effectively compensate for the attitude angle error of MEMS gyro caused by random vibration. This study can be a reference to the application of low-cost MEMS gyro in aircraft navigation. (2012) Trans Tech Publications  Switzerland.  
Study on sub-pixel techniques for accurate image measurement of displacement (EI CONFERENCE) 会议论文
2011 2nd International Conference on Advanced Measurement and Test, AMT 2011, June 24, 2011 - June 26, 2011, Nanchang, China
Xie Z.; Zhang X.
收藏  |  浏览/下载：12/0  |  提交时间：2013/03/25
A new approach to realize UART (EI CONFERENCE) 会议论文
2011 International Conference on Electronic and Mechanical Engineering and Information Technology, EMEIT 2011, August 12, 2011 - August 14, 2011, Harbin, China
Wang Y.; Song K.
收藏  |  浏览/下载：23/0  |  提交时间：2013/03/25
In order to connect DSP which has synchronous serial ports to the devices implementing asynchronous communications protocol  a method to implement UART communications based on programmable logic device is proposed in the paper. In the proposed method  the core function of UART is integrated in CPLD with VHDL. Firstly  UART data frame format and operational principle of UART were introduced after reviewing some methods to realize UART. The methods to implement UART transmitter  UART receiver and baudrate generator using VHDL were illustrated in detail. Then pre-simulation and synthesize of VHDL program were executed. Finally  the test with bit error rate was carried out on physical system. Experimental results indicate that 75 percent of the GLB are used by UART  and the bit error rate is less than 109. The experiment was implemented utilizing the RS-422 protocol and the baudrate is 62.5kb/s. The proposed method can satisfy the system requirements of high integration  stabilization  low bit error rate  strong anti-jamming and low cost. 2011 IEEE.  
The optical design of cubic phase plate testing system (EI CONFERENCE) 会议论文
2011 Symposium on Photonics and Optoelectronics, SOPO 2011, May 16, 2011 - May 18, 2011, Wuhan, China
Xu Y.; Lin H.; Zhu W.; Zhang Y.; Zhang X.
收藏  |  浏览/下载：18/0  |  提交时间：2013/03/25
Computer-generated holograms (CGH) have been widely used for years in optical testing of aspheric surfaces in combination with Fizeau interferometers. With the development of diffraction optics  computer technology  and micro-processing technology  the accuracy of the CGH testing can achieve a hundredth of a wave  and the cost is reduced greatly. CGH is capable of producing an optical wavefront with any desired shape. So it is fascinating and will have good prospects to test free-form surfaces using CGH. As the CGH can create any wavefront shape  it can also be used in unsymmetrical aspherical surfaces testing. Taking the cubic surface as an example  this paper gives a method to test unsymmetrical surfaces. This paper gives the design to test a cubic surface. And the separation of the diffraction orders and the binary process of the continuous CGH phase function are discussed in detail. The alignment tolerance of the test system and the CGH fabrication tolerance are analyzed. We also present an idea using a CGH and two spherical lenses as null lens to test the cubic surface when the surface deviation is great. 2011 IEEE.  
Study of experimental design and Response Surface method for surrogate model of computational simulation (EI CONFERENCE) 会议论文
2nd Annual Conference on Electrical and Control Engineering, ICECE 2011, September 16, 2011 - September 18, 2011, Yichang, China
Xi R.; Jia H.; Xiao Q.
收藏  |  浏览/下载：19/0  |  提交时间：2013/03/25
While the high-precision simulation is widely used in science and technology  Design of Experiment (DOE) based on Response Surface (RS) method can be employed in surrogate model to reduce the cost and error. In order to illustrate the relationship between parameters and response features  several DOE methods and Response Surface (RS) method are studied. The author used polynomial regression and RBF neural network based on orthogonal array to build a rocket aerodynamic discipline surrogate model respectively which proved their feasibility. From the results of the test case  conclusion is drawn that characteristic as well as acclimatization of DOE methods and different approximation should be considered for different issues  so the factors of cost and accuracy could reach a balance synthetically. 2011 IEEE.  
Semi-physical simulation of an optoelectronic tracking servo system based on C MEX S functions (EI CONFERENCE) 会议论文
2010 International Conference on Computer, Mechatronics, Control and Electronic Engineering, CMCE 2010, August 24, 2010 - August 26, 2010, Changchun, China
Juan C.; Junhong Z.
收藏  |  浏览/下载：20/0  |  提交时间：2013/03/25
To the design of an optoelectronic tracking servo system  we test the method [1  not only the reasonability of the control algorithm should be considered  2]. The simulation results verify the theoretical analysis. Because C MEX S function has the features of fast execute speed  but the cost and time as well. It is necessary to establish the simulation model for the system. Applying the C MEX S functions  independently generated program  we can build the every independent digital control modules in MATLAB/SIMULINK for the optoelectronic tracking servo system. In the paper  directly download to the hardwires  we apply the C MEX S function to the design of the practical optoelectronic tracking servo system. For the speed  we can design and debug the digital control modules in MATLAB/SIMULINK and then transform and download directly to DSP processor. 2010 IEEE.  position loop control and TV delay compensations  
Annular sub-aperture stitching interferometry for testing of large asphreical surfaces (EI CONFERENCE) 会议论文
International Symposium on Photoelectronic Detection and Imaging, ISPDI 2007: Optoelectronic System Design, Manufacturing, and Testings, September 9, 2007 - September 12, 2007, Beijing, China
Wang X.-K.; Wang L.-H.; Zheng L.-G.; Deng W.-J.; Zhang X.-J.
收藏  |  浏览/下载：67/0  |  提交时间：2013/03/25
Annular subaperture stitching interferometric technology can test large-aperture  and the PV and RMS of residual error of the full aperture phase distribution is 0.027 and 0.0023  high numerical aperture aspheric surfaces with high resolution  the relative error of PV and RMS is -0.53% and -0.31%  respectively. The results conclude that this splicing model and algorithm are accurate and feasible. So it provides another quantitive measurement for test aspheric surfaces especially for large aperture aspheres besides null-compensation.  low cost and high efficiency without auxiliary null optics. In this paper  the basic principle and theory of the stitching method are introduced  the reasonable mathematical model and effective splicing algorithm are established based on simultaneous least-squares method and Zernike polynomial fitting. The translation errors are eliminated from each subaperture through the synthetical optimization stitching mode  it keeps the error from transmitting and accumulating. The numerical simulations have been carried on by this method. As results  the surface map of the full aperture after stitching is consistent to the input surface map  the difference of PV error and RMS error between them is -0.0074 and -0.00052 ( is 632.8nm)  respectively  
Manufacturing and testing of the line-array fiber-optic image slicer based on silicon V-grooves (EI CONFERENCE) 会议论文
MEMS/MOEMS Technologies and Applications III, November 12, 2007 - November 14, 2007, Beijing, China
Liang J.; Guo P.; Liang Z.; Zhu Y.; Hou F.; Yao J.
收藏  |  浏览/下载：15/0  |  提交时间：2013/03/25
Linear fiber-optic image slicer is used more and more in spatial exploration and imaging system. In this paper  a plane arranging method of fiber-optic array based on Si-V grooves is established in order to improve the accuracy and reduce the cost of manufacturing. Firstly  the Si-V groove array is micro-machined with anisotropic etching process  then optical fibers are placed in the grooves orderly with plane arranging method. Secondly  the end surfaces of the device are polished  also the linear fiber-optic image slicer is packaged. Finally  some parameters are tested  including structure parameters  transmittivity and vibration test. Experimental results indicate that the maximum error accumulated in 2000 periods of the Si-V grooves is 0.5 m  the error of the height in Si-V grooves is less than 0.15m  the roughness of the end surface is less than 0.9nm. The transmittivity of the linear fiber-optic image slicer that without optical film is 51.46% at the wavelength of 632.8nm. After random vibration experiment  the ratio of the broken fiber increased by 0.1%. While the temperature reached 320C  the stress of epoxy will be 130Mpa  which is close to the limit resistance stress of 139Mpa  some cracks appeared.  
An image identification system of seal with fingerprint based on CMOS image sensor (EI CONFERENCE) 会议论文
ICO20: Optical Information Processing, August 21, 2005 - August 26, 2005, Changchun, China
Xue X.-C.; Zhang S.-Y.; Guo Y.-F.
收藏  |  浏览/下载：11/0  |  提交时间：2013/03/25
CMOS image sensors now become increasingly competitive with respect to their CCD counterparts  while adding advantages such as no blooming  simpler driving requirements and the potential of on-chip integration of sensor  analog signal conditioning circuits  A/D converter and digital processing functions. Furthermore  CMOS sensors are the best choices for low-cost imaging systems. An image identification system based on CMOS image sensor is used to identify the seal images that include fingerprint  and then determine whether the seal is fake or not. The system consists of a color CMOS image sensor (OV2610)  a buffer memory  a CPLD  a MCU (P89C61X2)  a USB2.0 interface chip (ISP1581) and a personal computer. The CPLD implement the logic and timing of the system. The MCU and the USB2.0 interface chip deal with the communications between the images acquisition system and PC. Thus PC can send some parameters and commands to the images acquisition system and also read image data from it. The identification of the images of seal is processed by the PC. The structure and scheme of the system are discussed in detail in this paper. Several test images of seal taken by the system are also provided in the paper.  
Developing of in-suit long trance profiler for testing slope error of aspherical optical Elements (EI CONFERENCE) 会议论文
ICO20: Optical Devices and Instruments, August 21, 2005 - August 26, 2005, Changchun, China
Zhou C.; Li H.; Chen C.; Zhou C.; Qian S.
收藏  |  浏览/下载：25/0  |  提交时间：2013/03/25
Profile error of super smooth surface of optical elements at X-ray/EUV in synchrotron radiation (SR) light beam line is described as slope error of them generally. The Long Trace Profiler (LPT) is used for testing surface slope error of SR optical elements in world generally. It is requisite to use In-suit LTP measuring surface thermal distortion of SR optical elements with high heat under high bright SR source. Authors design an In-suit LTP by means of co-path interferometer with pencil light beam. The instrument not only can be used for testing slope error of mirrors in Lab. also in situation test the distortion of mirror with high heat load at synchrotron light beam line. The device can be used to test various absolute surface figures of optical elements such as aspherieal  spherical and plane. It is needless standard reference surface. It is named by LTP-III. This paper describes its basic operating principle  optical system  mechanical constructions  DC serve motor control system  array detector  data acquisition system and computer system for controlling and data analysis of LTP-III. The Instrument has advantages of high accuracy  low cost  multifunction and wide application. Length of surface measured of optical element accuracy is 0.04 arcsec.  

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