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Polarization stabilized VCSELs by displacement Talbot lithography-defined surface gratings 期刊论文  OAI收割
Optik, 2019, 卷号: 183, 页码: 579-585
作者:  
Y.Y.Liu;  X.Zhang;  Y.W.Huang;  J.W.Zhang;  W.Hofmann
  |  收藏  |  浏览/下载:50/0  |  提交时间:2020/08/24
Model Magnet Development of D1 Beam Separation Dipole for the HL-LHC Upgrade 期刊论文  OAI收割
IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY, 2015, 卷号: 25, 期号: 3, 页码: 4000505
作者:  
Nakamoto;  Tatsushi;  Sugano;  Michinaka;  Xu
收藏  |  浏览/下载:39/0  |  提交时间:2016/04/18
Structural design of large aperture rectangular mirror for space telescope (EI CONFERENCE) 会议论文  OAI收割
2nd International Conference on Civil Engineering and Transportation, ICCET 2012, October 27, 2012 - October 28, 2012, Guilin, China
作者:  
Li Z.;  Li Z.
收藏  |  浏览/下载:41/0  |  提交时间:2013/03/25
Structural design of large aperture mirror is one of the key technologies for space telescope development. To meet the requirements of high stiffness  strength and thermal dimensional stability  some factors such as support scheme  materials selection  lightweight design and flexible support design were taken into account. The three supports location of the mirror was determined according to the modal analytical solution. By adjusting the parameters of flexure hinge  influences of gravity  assembly stress and thermal stress on the mirror were reduced obviously. Finite element analysis (FEA) results indicate that the surface accuracy reach to rms10.2nm and 10.8nm under the gravity along optical axis direction and 5C uniform temperature rise respectively  the fundamental frequency of the mirror component is 268Hz. Dynamics test shows that the first order natural frequency is 256Hz  which shows an error less than 5% compared to FEA results. (2013) Trans Tech Publications  Switzerland.  
Study on ultra-light secondary baffle for coaxial two-mirror telescope (EI CONFERENCE) 会议论文  OAI收割
2012 9th IEEE International Conference on Mechatronics and Automation, ICMA 2012, August 5, 2012 - August 8, 2012, Chengdu, China
作者:  
Zhang L.;  Zhang L.
收藏  |  浏览/下载:61/0  |  提交时间:2013/03/25
The coaxial two-mirror telescope consists of two mirrors facing each other. Classical two-mirror arrangements are Gregorian and Cassegrain. These systems are usually applied to space telescopes and often have optical baffles to prevent stray light from entering the focal plane. The optical baffles consist of concentric rings suspended between the secondary and the primary mirror. The secondary baffle for a large two-mirror optical system is designed and analyzed in this paper. According to mission of a telescope  the structure should have high stiffness and high reliability and light weight. Compared with invar  aluminum alloy and titanium alloy  carbon fiber composite is currently the best material in terms of weight-to-strength ratio. It also has advantages of high temperature tolerance and low thermal expansion. So carbon fiber composite is chosen as material to meet requirements of the coaxial telescope. In this paper  optimization method based on finite element analysis (FEA) is used for design the secondary baffle. Minimum weight of the baffle is chosen as an objective function. Thicknesses of former tube and vanes are chosen as variables. Analysis results show that the designed secondary baffle has maximum diameter of 180mm  total length of 120mm and weighs 142g. And its fundamental frequency reaches 651Hz. Therefore the baffle has many advantages  such as ultra-light weight  high stiffness and dimensional stability  etc. The optimization method and the baffle design can be helpful to other coaxial telescopes  such as Cassegrain  Gregorian and their subdivisions. 2012 IEEE.  
Design and optimization of supporting structure for scanning mirror in aviation remote sensor (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:  
Yang H.
收藏  |  浏览/下载:28/0  |  提交时间:2013/03/25
An optical supporting structure is studied to improve its structure stiffness and reduce the rotate error to meet the requirement of aviation remote sensor. A formula to calculate fundamental frequency is proposed using Rayleigh-Ritz method  and a method of is analyzed. By means of OPTISTRUCT software  the maximum fundamental frequency is converted to object function  the deformation under the gravity and the mass are assigned to state variable  wall thicknesses of the structure are converted to design variables. The analysis and test results indicate that the fundamental frequency of designed optical supporting structure has been improved 37.2 Hz from 96.9 Hz  which guarantee the reliability of the sweep mechanism  and the rotate error is 4.89  which is satisfied for the rotate accuracy in plunge angle. The method of optimization has a certain instructional significance for the design of supporting structures in aviation remote sensor. 2011 IEEE.  
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  
A design on a control method of a new type of focal plane shutter (EI CONFERENCE) 会议论文  OAI收割
2010 International Conference on Computer, Mechatronics, Control and Electronic Engineering, CMCE 2010, August 24, 2010 - August 26, 2010, Changchun, China
Xue L.; Ming L.; Zheng L.-N.; Zhou J.-F.; Zhang H.-W.; Zhang J.-C.
收藏  |  浏览/下载:33/0  |  提交时间:2013/03/25
In order to ensure appropriate exposure time  and no exposure while electric charge is transferring after taking a photograph  it is necessary to have the shutter mechanism cooperate with CCD for area CCD aerial cameras. The ground object illumination has a wide range which is from 4000Lx to 100000Lx  so a shutter which is high efficient and a continuous stepless adjustment are also required. This paper introduces the fundamental principle  structural design and control procedure about this new focal plane shutter. Under the control of DSP  the velocity of shutter curtain governed by the shutter motor can be not only precisely controlled  but also the durability and the reliability are increased. The experiment results have shown that this new shutter has the higher stability of movement  long life span with more than 105 operating times  a wide range of exposure time from1/ 50s to 1/ 320s(depending on the slit width)and the exposure error is less than 10%. With the CCD gain adjustment  the performance of this shutter is fully satisfied with the requirements of area CCD aerial cameras. 2010 IEEE.  
Optimum Design of Vibrating Cantilevers: A Classical Problem Revisited 期刊论文  OAI收割
Journal of Optimization Theory and Applications, 1995, 卷号: 84, 期号: 3, 页码: 635-652
作者:  
Fei-Yue Wang
收藏  |  浏览/下载:20/0  |  提交时间:2017/02/15
Optimum Design of Vibrating Cantilevers: A Classical Problem Revisited 期刊论文  OAI收割
Journal of Optimization Theory and Applications, 1995, 卷号: 84, 期号: 3, 页码: 635-652
作者:  
Fei-Yue Wang
  |  收藏  |  浏览/下载:8/0  |  提交时间:2017/07/15