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	Analysis on the influence of random vibration on MEMS gyro precision and error compensation (EI CONFERENCE) 会议论文 OAI收割 2011 3rd International Conference on Mechanical and Electronics Engineering, ICMEE 2011, September 23, 2011 - September 25, 2011, Hefei, China 作者: Li M. 收藏 \| 浏览/下载：21/0 \| 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 of horizontal shafting with spherical four-way structure (EI CONFERENCE) 会议论文 OAI收割 2012 International Conference on Optoelectronics and Microelectronics, ICOM 2012, August 23, 2012 - August 25, 2012, Changchun, China 作者: Yang L.; Yang L. 收藏 \| 浏览/下载：30/0 \| 提交时间：2013/03/25 Altazimuth photoelectric theodolite level shaft U-type and T-type structure but with the expanding field of applications of photoelectric theodolite the horizontal shaft structure occur great changes. For example in the marine environment shipboard conditions the instrument has a waterproof corrosion-resistant easy maintenance and other functions while carrier-based optoelectronic devices from a single visible television configure the development of integrated infrared system and ranging system as one of the single-station measurement system due to the spherical structure has sufficient internal space exactly adapted to this need. In this paper the horizontal axis of a spherical four-way structure. From aspects of the spherical four-way split in the form and shafting design and finite element analysis of the detailed design. A spherical four-way horizontal axis system diameter 550mm weight 19kg sphere in the 40kg load the maximum deformation of 3.3m fully meet the requirements. The shaft of the structure of the shaking is less than 2 arc seconds the vibration test the re-examination instrument accuracy change is less than 1 arc seconds. Verify that the structure is stable and reliable. 2012 IEEE.
	Random vibration analysis on the support of strapdown inertial navigation system (EI CONFERENCE) 会议论文 OAI收割 2nd Annual Conference on Electrical and Control Engineering, ICECE 2011, September 16, 2011 - September 18, 2011, Yichang, China 作者: Li M. 收藏 \| 浏览/下载：27/0 \| 提交时间：2013/03/25 Vibration of the support is an important factor to the accuracy of strapdown inertial navigation. To get vibration characteristics of the support FEM model of the support was created with Ansys and then response characteristics were analyzed on the support under the separated random loads during carrier flight including the phases of subsonic and subsonic. To validate the analysis method wide band random vibration test was done on the points of the support which are used for mounting inertial instruments. The comparison of the analysis and the test data shows that the relative error of analysis result is not more than 13%. According to the two results the support structure was improved. Finally random vibration analysis was carried out on the improved one. The result shows that the acceleration response was largely reduced than before. This research can be a reference of performance improvement of the strapdown inertial support and navigation system precision. 2011 IEEE.
	Buffer and vibration optimization of missile data recorder structure (EI CONFERENCE) 会议论文 OAI收割 2011 International Conference on Mechatronics and Materials Processing, ICMMP 2011, November 18, 2011 - November 20, 2011, Guangzhou, China 作者: Zhang J.; Zhang J.; Zhang J. 收藏 \| 浏览/下载：28/0 \| 提交时间：2013/03/25 On the analysis of the original data recorder the stress wave theory is the elastic theory can explain the filter buffer question from the micro-small space made several key problems clear when buffer and damping from this designed a composite structure for vibration reduction distinguished between a cushion theory and application field of stress wave theory which made the dynamic stress of protected component down about one order of magnitude. Optimization with Isight and Ls-dyna the traditional rigid spring-buffer model whose object is to reduce the impact of acceleration that can not accurately describe the elastic force of the part of the actual situation the protected component's dynamic stress down about 69.3% and the data recorder's quality 300g lower finally passed the Marshall Hammer test successfully. 2011 Trans Tech Publications.
	Application of particulate reinforced aluminum matrix composite in airborne photoelectric turret (EI CONFERENCE) 会议论文 OAI收割 2011 International Conference on Electric Information and Control Engineering, ICEICE 2011, April 15, 2011 - April 17, 2011, Wuhan, China 作者: Wang P. 收藏 \| 浏览/下载：24/0 \| 提交时间：2013/03/25 In order to design and manufacture more excellent airborne photoelectric stable turret modulus of elasticity of 213 GPa and thermal expansion coefficient of 7.9106/K. The frame has decreased the maximum deformation by by 60% and increased the fundamental frequency by 65% as compared with those of aluminum alloy materials a new type of aeronautical material-particulate reinforced aluminum matrix composite (SiC/Al composite) is investigated. Several crucial technologies respectively as shown by finite element analysis results. Those are confirmed by vibration test furthermore. Therefore such as pressureless infiltration technology a significant lightening effect is achieved and the thermal control load is also reduced. The test result indicates that the stable accuracy of the system achieves 19.8rad and the optical-axis parallelism of pay load is 0.1mrad. The research applies the SiC/Al composites to airborne photoelectric platforms interface reaction controls and plate's welding are systematically studied. Then which makes a effective exploration for the new aeronautical material's application. 2011 IEEE. using SiC/Al composites the airborne photoelectric stable turret frame is successfully prepared in density of 2.94 g/ cm3
	Gimbal displacement error analysis on an electro-optical seeker (EI CONFERENCE) 会议论文 OAI收割 Optical Design and Testing IV, October 18, 2010 - October 20, 2010, Beijing, China 作者: Zhang X.; Zhang X.; Zhang X. 收藏 \| 浏览/下载：32/0 \| 提交时间：2013/03/25 It is essential to analyze the gimbal displacement errors for a seeker due to the importance for cueing of targets and tracking for the final approach. Otherwise for a seeker electro-driven with a concentric glass dome the large errors will decrease the picking pointing and tracking precision rooted from the displacement errors existing between the rotation center of the optical system and the gimbal. And the gimbaled camera system displacement errors are never eliminated but reduced due to the geometric errors consists of geometric tolerances of gimbal structure manufacture installation and vibration coming from working environment. In this paper the gimbal displacement errors in an electro-optically stabilized platform resulting from geometric errors and environment errors were analyzed and shown in detail. The mathematical modal of the gimbal displacement errors created based on multi-body dynamics demonstrated the connection between the gimbal displacement errors and the stabilized platform. Taking a visible light image seeker as a case the diameter is 120mm and the geometric tolerances came from the values of primary design and the vibration data came from the environmental vibration test on the pitch-yaw seeker and at the same time the errors resulting from installation were considered too. Based on calculating the maximum gimbal displacement error will reach to 0.2mm for pitching angle smaller than 40 and yawing angle smaller than 60. However the critical parts have been found out according to the probability theory and the reliability analysis successfully used in the paper and finally the maximum gimbal displacement error reduced to 0.1mm which is acceptable corresponding to the picking pointing and tracking precision for an optical imaging seeker. 2010 Copyright SPIE - The International Society for Optical Engineering.
	Optimal design of strap-down inertial navigation support under random loads (EI CONFERENCE) 会议论文 OAI收割 2010 IEEE International Conference on Information and Automation, ICIA 2010, June 20, 2010 - June 23, 2010, Harbin, Heilongjiang, China 作者: Li M. 收藏 \| 浏览/下载：29/0 \| 提交时间：2013/03/25 In order to realize miniaturization and light weight of the strap-down inertial navigation system and then to make sure that it works well under random loads optimal design is applied to the strap-down inertial navigation support with the methods of topology optimization and size optimization. Firstly based on the installation requirement of devices and connection requirement of the support and the carrier the initial structure of the support is designed. Topology optimization with FEA software ANSYS is adopted on the initial structure to get the basic one. Then 5 critical sizes are chosen as design variables and the support structure is optimized by means of size optimization to reach light weight with satisfying the requirement of dynamic stiffness. Finally random vibration analysis is applied to the initial structure. In the mean time random vibration test is carried out to qualify the analysis method. After the qualification a random vibration analysis is applied to the optimized support structure to get the rms of displacement response and acceleration response of the support to validate whether the optimized structure is appropriate. The results indicate that the dynamic stiffness of the optimized support structure satisfies the design requirements and its weight is lighter 49.38% than that of the initial one. This research can be a reference to the structure design of supports under random loads and the result has been applied to the development and manufacture of a prototype aerocraft. 2010 IEEE.
	Design and test of focusing mechanism of space camera (EI CONFERENCE) 会议论文 OAI收割 5th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Design, Manufacturing, and Testing of Micro- and Nano-Optical Devices and Systems, April 26, 2010 - April 29, 2010, Dalian, China 作者: Li Y.; Li Y.; Li Y.; Wang H.; Wang H. 收藏 \| 浏览/下载：28/0 \| 提交时间：2013/03/25 According to the focal depth and work environment of a space camera a focusing mechanism is designed which consists of precision screw ball transmission and linear bearing guidance and accuracy improving. The dynamic- strike- resistance adaptability to temperature and vacuum are considered into the reliable design method. Furthermore the linearity error the structure stability and the mechanism work situation in high and low temperature are tested. The result is that the linearity error of the mechanism is less than 0.003 mm and the sway error of vertical way and level way of the mirror is less than 20''. The linearity error of the mechanism and the sway error of the mirror remain unchanged after vibration test. The mechanism can work in the complex space environment. 2010 SPIE.
	Manufacturing and testing of the line-array fiber-optic image slicer based on silicon V-grooves (EI CONFERENCE) 会议论文 OAI收割 MEMS/MOEMS Technologies and Applications III, November 12, 2007 - November 14, 2007, Beijing, China 作者: Zhu Y. 收藏 \| 浏览/下载：22/0 \| 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.