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	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：62/0 \| 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.
	The structure design and analysis of predigest laser combine bind and extend bind flat roof (EI CONFERENCE) 会议论文 OAI收割 2011 International Conference on Advanced Engineering Materials and Technology, AEMT 2011, July 29, 2011 - July 31, 2011, Sanya, China 作者: Wang B.; Wang H.; Wang H.; Wang H.; Wang H. 收藏 \| 浏览/下载：31/0 \| 提交时间：2013/03/25 This paper put forward a kind of predigest laser combine bind and extend bind flat roof structure which is founded as fission flat roof and can be built in an little room 1280mm990mm815mm. This flat roof space location can be adjusted. This kind of seat can ensure the system complete laser combine and close as high precision. In this paper we designed the laser combine and close whole structure and install design. At last we did some finite statics analysis to some important parts. This design can ensure every laser fire directional adjust mete lower 30' and the flat roof quality is 770kg. The transition benchmark flat roof system most meet and emergency is 0.005mm at the premise of bear the weight of turn flat laden. It can be seen that this structure can satisfy the request of many lasers small space laser extend bind and adjust. This kind can be extended to other light combine bind and extend bind structure design. (2011) Trans Tech Publications Switzerland.
	The research of the high precision universal stable reconnaissance platform in near space 会议论文 OAI收割 nternational symposium on photoelectronic detection and imaging 2011: space exploration technologies and applications, beijing, china, may 24, 2011 - may 26, 2015 YangHong-Tao; CaoJian-Zhong; FanZhe-Yuan; ChenWei-Ning 收藏 \| 浏览/下载：37/0 \| 提交时间：2012/07/09 Near space Stable platform Payload Light-weight design stabilization accuracy
	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.
	Development and radiance calibration of three-waveband camera (EI CONFERENCE) 会议论文 OAI收割 International Symposium on Photonics and Optoelectronics, SOPO 2010, June 19, 2010 - June 21, 2010, Chengdu, China 作者: Wang J.; Liu Y.; Liu Y.; Sun Q.; Liu Y. 收藏 \| 浏览/下载：32/0 \| 提交时间：2013/03/25 An imaging system with three-waveband sharing one lens and an area CCD was developed. By rotating different filters into the beam path the required waveband was selected. The optical system which can image in ultraviolet visible and near infrared region was designed and the signal collecting system was integrated. The optical design and system integration have some advantages such as low cost small size and light in weight. To obtain a high imaging quality the radiation calibration is carried out in order to establish the relation between the average grey level of output image and the input radiance from the integrating sphere. According to the calibration data in experiments the radiation dynamic range and the best working point of the system are determined. The experiment result shows that the dynamic range of the image system is maximal when the exposure time is 8ms in ultraviolet 0.5ms in visible and 0.125ms in near infrared region. 2010 IEEE.
	The design of composite optical encoder (EI CONFERENCE) 会议论文 OAI收割 9th International Conference on Electronic Measurement and Instruments, ICEMI 2009, August 16, 2009 - August 19, 2009, Beijing, China Liang L.; Wan Q.; Qi L.; He J.; Du Y.; Lu X. 收藏 \| 浏览/下载：19/0 \| 提交时间：2013/03/25 In order to improve minimize volume lighten the weight of Measurement and Control Equipment ??the design of a composite optical encoder is put forward in this paper. The composite encoder can achieve the angle measurement as the absolute encoder and the servocontrol as the increment encoder. Base on the requirement of the Measurement and Control Equipment the Composite code disc and the slot is designed then the precision test is implemented on the composite optical encoder. The experimental result shows that the composite optical encoder not only output the measurement of the angle but also provides speed feedback control signal. It has advantages of small volume light weight which can meet the requirements of Measurement and Control Equipment. 2009 IEEE.
	Research on the support structure of the primary mirror of large-aperture 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 Yang W.; Jingxu Z. 收藏 \| 浏览/下载：28/0 \| 提交时间：2013/03/25 Large-aperture telescope can be used in surveying battlefield researching landform searching object real-time monitoring imaging detecting and identifying spatial targets and so on. A large-aperture telescope for achieving high resolution power is designed to monitor spatial target and image in real time. Real-time monitoring plays an important role in military conflicts. The orbit parameter of object quantity geometrical shape parameter and so on can be obtained by detect spatial target. With the development of optical technology people require larger aperture in optics-electronic (OE) system. By increasing optical aperture the ability of collecting light and resolution power in the system can be enhanced. But the support structure of the primary mirror of large-aperture telescope will be a very difficult problem. With the increase of primary mirror aperture the weight of the primary mirror will become larger than before. The root mean square (rms) of the primary mirror is affected by many factors such as deadweight deformation of heat environment and so on. Due to the primary mirror of telescope is an important component of telescope system. By reducing the weight of primary mirror precision of the system is ensured. During the designing phase one can consider the supporting project of the primary mirror synthetically and analyze it roundly according to technical requirement of optical system and the effect factors. The final structural design can be reasonable. In an astronomical telescope the surface of reflector is an important part for collecting dark radiation of celestial bodies. Its surface shape will have an effect on collecting efficiency of telescope radiant energy directly. So the rms must be very high. Optical system of large aperture small wavelength and small focus can receive maximal light intensity. For ground-based optical astronomical telescope the design proposed in the paper can satisfy the requirement of the possible minimum atmosphere seeing at astronomical observatory site and exert the use efficiency of the telescope adequately. So the accuracy of the traditional surface of reflector can assure that 90% of all the light energy can be focused on within the angle diameter range of the minimum atmosphere seeing then 100% of light energy should be focused on the angle diameter range of minimum atmosphere seeing. Because the rms of mirror is very high precise surface machining and accurate the support of mirror are very important tasks during designing and manufacturing the telescope. In the paper various support techniques of a large-aperture telescope primary mirror are discussed and a 3.5 meter telescope system at the Starfire Optical Range (SOR) overviewed simply which was operated by the Directed Energy Directorate of the Air Force Research Laboratory Kirtland AFB NM USA from the ground-based O-E system for the observations of spatial target. We also analyze Theoretical elastic deformation of the Steward Observatory 2.3 meter mirror is analyzed.