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	Evaluation of diffuse solar radiation models in Northern China: New model establishment and radiation sources comparison 期刊论文 OAI收割 RENEWABLE ENERGY, 2017, 卷号: 103, 页码: 708-720 作者: Cao, Fei; Li, Huashan; Yang, Tian; Li, Yan; Zhu, Tianyu \| 收藏 \| 浏览/下载：28/0 \| 提交时间：2017/10/13 Diffuse Solar Radiation Model Establishment Solar Database Trnsys Solar Energy
	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：47/0 \| 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.
	Modulation transfer function in seeker camera limits resulting from missile flutter caused by aerodynamic force (EI CONFERENCE) 会议论文 OAI收割 2010 2nd International Conference on Industrial Mechatronics and Automation, ICIMA 2010, May 30, 2010 - May 31, 2010, Wuhan, China 作者: Zhang X.; Zhang X.; Zhang X. 收藏 \| 浏览/下载：25/0 \| 提交时间：2013/03/25 The imaging quality of seeker in flight mode has been evaluated through analyzing the effects of missile flutter on optical modulation transfer function (MTF) of the optical system. Firstly the data of transverse vibration has been processed to eliminate the trend term caused by the trajectory then obtained the displacement with two times trapezoidal integration. For the side rotation the high frequency noise interference in the data has been filtered by using five-point moving average method. Took this model as the quivering rule between the object and the image and then analyzed the effects of the transverse vibration and the side rotation on imaging quality through MTF. By calculation the r.m.s value of the image motion caused by missile transverse vibration is 0.026mm and the side rotation angle is 0.0044 . Through the establishment of two modulation transfer functions (MTF) of image random vibration and linear vibration the results show that the image quality had declined and the effect of transverse vibration on image quality is obvious. Through improving the rigidity of the missile and selection of small focal length optical system and shorten the time of exposure can improve the imaging quality of the seeker. 2010 IEEE.
	Space optics remote sensor focusing components mechanics characteristic analysis based on FEM (EI CONFERENCE) 会议论文 OAI收割 International Symposium on Photoelectronic Detection and Imaging 2009: Material and Device Technology for Sensors, June 17, 2009 - June 19, 2009, Beijing, China 作者: Wang B.; Ren J.-Y.; Wang B. 收藏 \| 浏览/下载：147/0 \| 提交时间：2013/03/25 Space optical remote sensor is very important in many fields of science and military significance. It is widely applied. Space optical remote sensor design and manufacturing require precision and stability. Focusing mechanics is an important component of remote sensors. Focusing mechanics can guarantee the stability of the entire mechanics focusing accuracy therefore the stability of research focusing mechanics is very important. In order to guarantee the space optics remote sensor focusing mechanics the stability takes steps the space optics remote sensor focusing organization mechanics characteristic analysis from the classics contact theory. This article uses international general non-linear finite element analysis software ABAQUS to carry on mechanics characteristic analysis to the space optics remote sensor focusing mechanics. First acts according to the focusing mechanics unique feature carries on the finite element to the structural model the grid division the material attribute disposition and the boundary condition indeed grades. Then establishment contact non-linear finite element model and to focusing organization finite element model infliction unit action. Like this contacts the result and the equivalent static analysis result which the nonlinear analysis obtains carries on the contrast and the analysis. This article last count result modality is 90HZ satisfies the space optics remote sensor structure overall modality to request to be bigger than 50HZ.This article when carries on the dynamic analysis extracts the structure kinetic energy and the acceleration curve. In the dynamic analysis obtained transient response analysis modality 70.5Hz this also is bigger than 50HZ. The dynamic analysis indicated the structure dynamic stability has the distinct enhancement has provided certain foundation for the space optics remote sensor following development work reduced the overall system development cycle. 2009 SPIE.