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	Structural design of primary mirror subassembly for space telescope (EI CONFERENCE) 会议论文 OAI收割 2nd International Conference on Mechatronics and Applied Mechanics, ICMAM 2012, December 8, 2012 - December 9, 2012, Taiwan 作者: Xu H. 收藏 \| 浏览/下载：63/0 \| 提交时间：2013/03/25 In order to design a large aperture primary mirror with the diameter of 1150 mm the parameters impacting on gravity deformation of the mirror were analyzed and discussed in detail including material selection diameter-thickness ratio the number of the support points location selection and lightweight structure etc. A novel space mirror structure system was put forward and its back was opened and supported by six points on back. The dynamic and static and thermal characteristics were analyzed based on the finite element method. Analysis results showed the surface figure accuracy reached to RMS 14.5nm under the action of gravity load along the optical axis direction and the first-order natural frequency was 214Hz which met to the designed indexes requirements. (2013) Trans Tech Publications Switzerland.
	Tracking error modeling of the theodolite based on GRNN method (EI CONFERENCE) 会议论文 OAI收割 2nd International Conference on Frontiers of Manufacturing and Design Science, ICFMD 2011, December 11, 2011 - December 13, 2011, Taichung, Taiwan 作者: Li M. 收藏 \| 浏览/下载：25/0 \| 提交时间：2013/03/25 To meet the requirement of high tracking accuracy as well as develop more reasonable evaluation method in this paper the General Regression Neural Network (GRNN) has been applied to build the tracking error model of the theodolite. First we analyze the nonlinear factors in the theodolite. Second we discuss the principle of GRNN including its structure the function as well as its priors. Third we build the tracking error model based on GRNN and verify the model through the different parameters. The result indicated that the network model based on GRNN has high accuracy and good generalization ability. It could instead the real system to a certain extent. The research in this paper has important value to the engineering practice.
	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：23/0 \| 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.
	Study on the Driving Scheme of a 4-m Alt-azimuth Telescope (EI CONFERENCE) 会议论文 OAI收割 3rd International Symposium on Advanced Optical Manufacturing and Testing Technologies, AOMATT 2007: Large Mirrors and Telescopes, July 8, 2007 - July 12, 2007, Chengdu, China 作者: Zhang J.; Dai S.; Zhao Y.; Zhao Y.; Zhao Y. 收藏 \| 浏览/下载：23/0 \| 提交时间：2013/03/25 By summarizing the corresponding parameters Of the driving system of a 4-m Alt-azimuth telescope some unit techniques like the driving modes and structure angular position measurement methods in detail have been analyzed in the paper. A set of primary schemes for astronomical applications including the altitude axes being driven by 2 DC torque motors the azimuth by 4 DC torque motors using helical gears and two pieces of the 27-bit segment tape encoders for each set of axes is proposed. To meet practical engineering needs the shafting motion parameters are designed and motor elementary parameters are primarily calculated to offer the important references for further study on system driving model and prototype development.
	The study on the compound X-ray refractive lens using LIGA technique (EI CONFERENCE) 会议论文 OAI收割 MEMS/MOEMS Technologies and Applications II, November 10, 2004 - November 12, 2004, Beijing, China 作者: Wang L.; Wang L.; Wang L.; Wang W.; Wang W. 收藏 \| 浏览/下载：21/0 \| 提交时间：2013/03/25 A theoretical method of focusing X-rays by the compound X-ray refractive lens is presented in this paper. The authors report their resent theoretical results including the material selection and structure parameters for such a device. As an example a compound X-ray refractive lens with PMMA material is designed. The detailed fabrication process of the PMMA compound lens by LIGA technology is described. Moreover some measured results by means of SEM are also shown. The structure height of one of the PMMA compound lens is measured to be 500m.