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	Design of motion compensation mechanism of satellite remote sensing camera (EI CONFERENCE) 会议论文 OAI收割 International Symposium on Photoelectronic Detection and Imaging 2011: Space Exploration Technologies and Applications, May 24, 2011 - May 26, 2011, Beijing, China Gu S.; Yan Y.; Xu K.; Jin G. 收藏 \| 浏览/下载：48/0 \| 提交时间：2013/03/25 With the development of aerospace remote sensing technology the ground resolution of remote sensing camera enhances continuously. Since there is relative motion between camera and ground target when taking pictures the target image recorded in recording media is moved and blurred. In order to enhance the imaging quality and resolution of the camera the image motion had to be compensated. In order to abate the effect of image motion to image quality of space camera and improve the resolution of the camera the compensation method of image motion to space camera is researched. First the reason of producing drift angle and adjustment principle are analyzed in this paper. This paper introduce the composition and transmission principle of image motion compensation mechanism. Second the system adopts 80C31 as controller of drift angle and adopts stepping motor for actuators and adopts absolute photoelectric encoder as the drift Angle measuring element. Then the control mathematical model of the image motion compensation mechanism are deduced and it achieve the closed-loop control of the drift angle position. At the last this paper analyses the transmission precision of the mechanism. Through the experiment we measured the actual precision of the image motion compensation mechanism and compared with the theoretical analysis. There are two major contributions in this paper. First the traditional image motion compensation mechanism is big volume and quality heavy. This has not fit for the development trend of space camera miniaturization and lightweight. But if reduce the volume and quality of mechanism it will bring adverse effects for the precision and stiffness of mechanism. For this problem This paper designed a image motion compensation that have some advantages such as small size light weight at the same time high precision stiffness and so on. This image motion compensation can be applicable to the small optics cameras with high resolution. Second the traditional mechanism control need to corrected fitting and iterative for the control formula of mechanism. Only in this way we can get the optimal control mathematical model. This paper has high precision of the control formula derived. It can achieve the high precision control without fitting It also simplify the difficulty of control mathematical model establishment. This paper designed the range of adjusting of image motion compensation mechanism between -5 +5. Based on choosing-5 -4 -3 -2 -1 0 +1 +2 +3 +4 +4 as the expectation value of the imaginary drift angle we get ten groups of the fact data in adjusting drift angle measured. The test results show that the precision of the drift angle control system can be achieved in 1. It can meet the system requirements that the precision of the control system is less than 3' and it can achieve the high-precision image motion compensation. 2011 SPIE.
	Station mode for attitude determination of small-multi-target with high speed (EI CONFERENCE) 会议论文 OAI收割 2010 International Conference on E-Product E-Service and E-Entertainment, ICEEE2010, November 7, 2010 - November 9, 2010, Henan, China 作者: Wang J.; Zhao L.; Li M. 收藏 \| 浏览/下载：27/0 \| 提交时间：2013/03/25 A key problem of attitude measurement of small-multi-target with high speed is how to decide the optimum of the CMOS stations. A multi-CMOS station mode is designed in this paper multiple CMOS videos were placed on two parallel sides in measurement system every two CMOS form an intersection viewing field multiple viewing field join to cover shooting range which can augment Effective Viewing Field(EVF) increase capture ratio of objects with high speed and measurement precision of small objects. When an object passes through the joint area it will be imaged separately on each CMOS focal plane. Multiple CMOS videos were triggered synchronously a sequence of image information was extracted the target attitude was confirmed by digital image processing technology. The merit of station mode is low cost large measurement scope extending freely and so on. 2010 IEEE.
	Analysis of measuring errors for the visible light phase-shifting point diffraction interferometer (EI CONFERENCE) 会议论文 OAI收割 2010 OSA-IEEE-COS Advances in Optoelectronics and Micro/Nano-Optics, AOM 2010, December 3, 2010 - December 6, 2010, Guangzhou, China 作者: Zhang Y. 收藏 \| 浏览/下载：19/0 \| 提交时间：2013/03/25 In order to improve the measuring accuracy of the visible light phase-shifting point diffraction interferometer (PS/PDI) for the extreme ultraviolet lithography (EUVL) aspheric mirrors the main measuring errors will be discussed in this paper. At first the elementary configuration and measuring principle of the visible light phase-shifting point diffraction interferometer are introduced briefly then the different errors which are possible to affect the measuring result are summed up the errors include PZT phase-shifting error detector nonlinearity error detector quantization error wavelength instability error and intensity instability error of the laser source vibration error air refractivity instability error and so on. Through detailed analysis and simulation the magnitude of these errors can be obtained. By analysing the reasons which cause these errors and the relationship between these errors and interferometer configuration parameters some methods are put forward to avoid or restrain these errors accordingly.
	Position servo control of a DC electromotor using a hybrid method based on model reference adaptive control (MRAC) (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 作者: Chen J. 收藏 \| 浏览/下载：27/0 \| 提交时间：2013/03/25 This paper dealed with position control problems of a DC motor servo system that had nonlinear friction and was subject to parametric uncertainties external disturbances etc. In order to overcame those unfavourable factors mentioned above a model reference adaptive control method was proposed to regulate the important and main speed loop in the positioning system which was designed with three closed control loop where a compensatory measure was given so as to counterbalance the friction torque disturbances. In addition the other two close loops were built in adjusting the position and the current of the servo system respectively that aimed to achieve the fast and precise positioning and increase dynamic stiffness against load disturbances. Experimental results illustrate satisfactory performances in steady state error load capability high rapidity and so on. 2010 IEEE.
	MMS protocol analysis and implementation base on embedding GSM/ GPRS wireless communication module (EI CONFERENCE) 会议论文 OAI收割 2009 International Conference on Information Technology and Computer Science, ITCS 2009, July 25, 2009 - July 26, 2009, Kiev, Ukraine Yuan Y.-P. 收藏 \| 浏览/下载：20/0 \| 提交时间：2013/03/25 The Multimedia Messaging Service(MMS) system mainly focus on supporting multimedia function by the GPRS channel transfer video file photo audio file text file and so on. Based on this function the implementation of the image communication between wireless modules between wireless module and mobile phone between wireless module and computer became true. This paper describe the MMS system framework based on the embedded GSM/GPRS wireless modules MMS system protocol and the software implementation of the MMS protocol. 2009 IEEE.
	Fabrication technique of large-scale lightweight SiC space mirror (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 G.; Zhang G.; Zhang G. 收藏 \| 浏览/下载：26/0 \| 提交时间：2013/03/25 Silicon carbide (SiC) is a new type candidate material for large-scale lightweight space mirror. Its low thermal distortion high stiffness high optical quality and its dimensional stability are better than other traditional optical substrate materials such as ULE Zerodure Beryllium (Be) and so on. In this paper the lightweight silicon carbide space mirror blank was fabricated by reaction sintering. As a space born mirror material silicon carbide must be an optical grade ceramic. So we prepared the silicon carbide green body with gel-casting method. Then some carbon materials were supplemented into the green body which will bring reaction-sintering with silicon in a vacuum furnace during 1500-1600C ultimately the reaction bonded silicon carbide was made. The diameter of SiC space mirror blank we have made is 680mm. If expanding the size of the vacuum furnace bigger mirror blank can be obtained. The test results show that the mechanical and thermal properties of RB-SiC are excellent with bending strength of 350MPa fracture toughness of 4.1 MPa·m1/2 and coefficient of thermal expansion(CET) of 2.6710-6/K. The surface roughness(RMS) could be better than 3nm.
	Study on the detection sensitivity of APS star tracker (EI CONFERENCE) 会议论文 OAI收割 3rd International Symposium on Advanced Optical Manufacturing and Testing Technologies: Optical Test and Measurement Technology and Equipment, July 8, 2007 - July 12, 2007, Chengdu, China 作者: Li J.; Li J.; Li J.; Liu J.; Liu J. 收藏 \| 浏览/下载：26/0 \| 提交时间：2013/03/25 Detection sensitivity is an important parameter of star tracker which can express detection limit of the weakest detected visual star magnitude. Detection sensitivity of APS star tracker is related to APS parameters optical system aperture and lens permeance rate SNR and so on. This paper the expressions of APS star detected signal and APS noise are given so signal-noise ratio (SNR) of star tracker can be obtained. And based on the theory inspecting signal from noise and optimal SNR threshold detection principle the detection sensitivity model can be obtained. The corresponding APS star tracker detection limit is obtain based on APS IBIS5 and general optical system parameter design. When SNR threshold is 8.1 which can obtain 99.9% detection probability we can calculate that the detection sensitivity is 6.5 visual magnitude.
	Novel fast measurement method of twist angle and optical retardation of liquid crystal display (EI CONFERENCE) 会议论文 OAI收割 Asia Display 2007, AD'07, March 12, 2007 - March 16, 2007, Shanghai, China Huang X.; Lu Y.-T.; Kong X.-J.; Jing H.; Fu G.-Z.; Jin H. 收藏 \| 浏览/下载：19/0 \| 提交时间：2013/03/25 A novel method is proposed to measure twist angle and optical retardation of liquid crystal display in this paper. The new method which is one of single-wavelength methods has three characteristics introducing a method of measuring the total intensity ratio of the transmitted light to eliminate the influence of absorption by the polarizer using circularly and homogeneously aligned LC cell (CH-LC) as a unique polarization-converting device analyzer using variable sector diaphragm and photodetector to detect the total intensity of transmitted light whose original polarization direction is continuously changed from 0 to arbitrary angle CH-LC liquid crystal display and so on. The twist angle () and optical retardation (nd) can be derived by using Jones matrix analysis and a curve fitting where and nd are fitting parameters. Experiment proved the results are accurate the process of operation is fast the devices are economical.