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	Research on mirror surface shape of space camera fitting based on SVD 会议论文 OAI收割 Beijing, China, 2019-07-07 作者: Huang, Tuo; Chen, Rong-Li; Chu, Chang-Bo \| 收藏 \| 浏览/下载：12/0 \| 提交时间：2020/03/04 mirror surface shape Zernike polynomials spherical mirror fitting precision Zernike polynomials terms singular value decomposition
	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.
	Data processing method of multi-position strap-down north seeking system based on SVD (EI CONFERENCE) 会议论文 OAI收割 2011 International Conference on Mechatronic Science, Electric Engineering and Computer, MEC 2011, August 19, 2011 - August 22, 2011, Jilin, China Shen C.-W.; Liu C.; Yu S.-B.; Wang Z.-Q.; Li J.-R. 收藏 \| 浏览/下载：36/0 \| 提交时间：2013/03/25 With the aim to fit the sin wave curve of a multi-position strap-down north seeking system and to calculate the real north angle accurately the principles of the system and the algorithm of singular value decomposition(SVD) are introduced. The factors influencing the measuring precision are also analyzed. Then the algorithm is adopted to fit curves. Experimental results indicate that the singular value decomposition is very precise for its error sum is 1.1102V and the squared error is 2.8mV. Moreover for phase angle measurement measured six times in same direction the squared error is 24 (1). The method based on SVD can satisfy the system precision requirements of curve-fitting north seeking systems. 2011 IEEE.
	Study of the neural network constitutive models for turfy soil with different decomposition degree (EI CONFERENCE) 会议论文 OAI收割 2011 2nd International Conference on Mechanic Automation and Control Engineering, MACE 2011, July 15, 2011 - July 17, 2011, Inner Mongolia, China 作者: Nie L. 收藏 \| 浏览/下载：19/0 \| 提交时间：2013/03/25 The turfy soil is of a special humus soil. The decomposition degree is the main factor on the physical and mechanical properties of turfy soil. To build the turfy soil constitutive model there are a few shortages such as the calculation cumbersome and low accuracy for parameter value with the method of traditional models. Furthermore those methods did not reflect the influence of strength that effected by decomposition degree of the turfy soil. In this paper the relationship of stress-strain with different decomposition degrees of turfy soil was carried out through indoor tests. Based on above experimental results an improved method which divided into different zones according to different decomposition degrees of turfy soil and calculated combining with neural network constitutive model is put forward. The result shows that the neural network of turfy soil has good fitting precision and good generalization ability. It can fully describe the influence of the turfy soil. 2011 IEEE.
	The method on the measurement of the aircraft attitude by the spatial cosines relationship of the single station and planes to the intersection the multi-station of electro-optical theodolite (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 Zhao L.-R.; Cao Y.-G. 收藏 \| 浏览/下载：16/0 \| 提交时间：2013/03/25 In order to realize the aircraft attitude measurement The paper advances electro-optical theodolite methods of measuring the aircraft attitude by using the spatial cosines relationship the single station theodolite and how to use intersection of the multi-station theodolite. The single station theodolite was introduced in a measured distance from the aircraft posture information. An exhaustive approach was used to access to the aircraft axis of the feature points and the location in the space was used to obtain space posture parameters. The multi-station theodolite was introduced to get the information of the aircraft flight attitude by method of using planes to the intersection. Two-dimensional image to obtain objective axis by fitting algorithm using Hough transform. And then Calculate the vertical distance of the origin to the target of the central axis and the origin to the target of the central axis of the angle between the normal and the X-axis obtaining the linear equation in the two-dimensional plane. Two-dimensional axis of the target image and the camera system's optical center only identified a space plane. The aircraft yaw axis angle and pitch angle can be obtained by getting the space axis using plains to the intersection method. Experimental results show that attitude angle error of the single station theodolite is less than 1 when its distance is less than 6000m and attitude angle error of the multi-station theodolite is less than 0.6 when its intersection angle is between 30 and 150. In this paper according to test result of precision comparing the mathematical model is correct and the algorithm is reasonable in extracting effective parameters of the aircraft's attitude. 2010 IEEE.
	Methods for integrated simulation of high-precision space optomechanical systems (EI CONFERENCE) 会议论文 OAI收割 3rd International Symposium on Advanced Optical Manufacturing and Testing Technologies, AOMATT 2007: Advanced Optical Manufacturing Technologies, July 8, 2007 - July 12, 2007, Chengdu, China Dong W.; Guang J.; Hong-bo Y. 收藏 \| 浏览/下载：26/0 \| 提交时间：2013/03/25 Each disciplinary has its own modeling and analysis tools to solve its own specific field problems. In order to achieve integrated simulation of high precision space optical systems and predict optical performance respective to the mechanical and thermal loads data must pass through different analysis tools. Simulation tools used in the thermal structural and optical design process and the relationship among them were first depicted and the integrated simulation methods were described in detail. Zernike polynomial fitting methods and interpolating approaches were also demonstrated. Because of the orthogonality of Zernike polynomials it was not probably used in some situations such as noncircular apertures and discrete data and the coupling of Zernike polynomial coefficients and other methods were also introduced in the paper. The toolkit OMTIA (Optical Mechanical and Thermal Integrated Analyzer) based on the methods was developed which appears as an indispensable tool for engineering practice.
	Based on Householder transform of the Zernike polynomial wave front fitting method to solve active optics correction force (EI CONFERENCE) 会议论文 OAI收割 Infrared Materials, Devices, and Applications, November 12, 2007 - November 15, 2007, Beijing, China 作者: Wu X.-X. 收藏 \| 浏览/下载：27/0 \| 提交时间：2013/03/25 Corrective force solving is a critical technology of the active optics. A method to solve active optics corrective force is introduced which is based on Householder transform of Zernike polynomial wave front fitting this method is different from the traditional least square method and Gram-Schmid orthogonal method because it does not bring ill-conditioned polynomial without constructing normal equation so it can avoid calculation error wave front fitting is precision. Based on the coefficient of the Zernike polynomial and the response function of the each actuator the stiffness matrix of the primary mirror is built and then adopting the damp least square method to calculate corrective force. Based on this method cp400m test mirror is simulated many times the calculation result approve: if the Householder transform is adopted wave front fitting is precision the result is stabilization and corrective effectiveness is better.