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浏览/检索结果: 共10条，第1-10条 帮助 限定条件 发表日期：2011    内容类型：会议论文    专题：长春光学精密机械与物理研究所    第一署名单位    第一作者单位    通讯作者单位     已选(0)清除 条数/页：5101520253035404550556065707580859095100   排序方式：请选择作者升序作者降序题名升序题名降序发表日期升序发表日期降序提交时间升序提交时间降序 Space camera dynamic image quality measurement and evaluation (EI CONFERENCE) 会议论文 3rd International Conference on Measuring Technology and Mechatronics Automation, ICMTMA 2011, January 6, 2011 - January 7, 2011, Shanghai, China Su W.; Zhang X. 收藏  |  浏览/下载：15/0  |  提交时间：2013/03/25 By using analysis of the infinity image of the space camera  we intend to obtain the curve of the dynamic modulation transfer function. We extract the pixel gray values at the image edge which distribute as a knife-edge function  and make differential calculation and Fourier transformation of it  and then we can obtain the dynamic MTF curve of the optical system. The value of the curve at the Nyquist frequency is the most important parameter that reflects the image quality. We add push-scanning imaging and environmental effects to the static MTF of space camera and compare the MTF value with the dynamic MTF at Nyquist frequency. The comparison result can help us verify the accuracy of the calculating results and the feasibility of our method. (2011) Trans Tech Publications.   Technology on fabrication of precise SiC aspherical mirror (EI CONFERENCE) 会议论文 2011 International Conference on Materials and Products Manufacturing Technology, ICMPMT 2011, October 28, 2011 - October 30, 2011, Chengdu, China Zhang Z. 收藏  |  浏览/下载：19/0  |  提交时间：2013/03/25 This paper represents a technique to produce the large size optical aspherical mirror by using reaction-bonded silicon carbide to meet the material requirements of the space used mirrors  based on the characters comparison of all types mirror material. Techniques are described in this paper  including the bonding procedure of silicon carbide to form a mirror shape  the CCOM technology for aspheric grinding  polishing on a home-developed tool -FSGJ-2  and the aspheric profilometry. A specialized Offner Null lens is also developed to measure the aspherical mirror with laser interferometer. With the technology depicted in the paper  a 502mm 298 mm off-axis SiC aspherical mirror is successfully made with a surface accuracy better than 1/50rms  the final result meets the design requirement. (2011) Trans Tech Publications.   Precise motion compensation based on weighted sub-pixel image matching (EI CONFERENCE) 会议论文 International Symposium on Photoelectronic Detection and Imaging 2011: Advances in Imaging Detectors and Applications, May 24, 2011 - May 26, 2011, Beijing, China Liang H. G. 收藏  |  浏览/下载：21/0  |  提交时间：2013/03/25 This paper proposed a sub-pixel image correlation algorithm that can get more Precise result  its principle is apply the distribute of relativity peak to get weighted multi-pixel comprehensive of location. Image correlation be as to calculates the greyscale relativity of image template and matching image  the relativity of correspond location where match best with template will be most high  and in its neighbour range  the relativity will be still keep high too. We used these pixel in this local area of calculated match point to get sub-pixel accuracy  the relativity of every pixel be used as its weight for participate the sub-pixel calculation. The sub-pixel location is more accuracy than the integer one  we applied this method to perform background compensation in processing the target detecting for video image sequence. At the end of this paper  some experiment data be proposed  it proved this sub-pixel image correlation can obtain better result. 2011 SPIE.   Random vibration analysis on the support of strapdown inertial navigation system (EI CONFERENCE) 会议论文 2nd Annual Conference on Electrical and Control Engineering, ICECE 2011, September 16, 2011 - September 18, 2011, Yichang, China Hao X.; Li M.; Jia H. 收藏  |  浏览/下载：17/0  |  提交时间：2013/03/25 Vibration of the support is an important factor to the accuracy of strapdown inertial navigation. To get vibration characteristics of the support  FEM model of the support was created with Ansys  and then response characteristics were analyzed on the support under the separated random loads during carrier flight  including the phases of subsonic and subsonic. To validate the analysis method  wide band random vibration test was done on the points of the support  which are used for mounting inertial instruments. The comparison of the analysis and the test data shows that the relative error of analysis result is not more than 13%. According to the two results the support structure was improved. Finally random vibration analysis was carried out on the improved one. The result shows that the acceleration response was largely reduced than before. This research can be a reference of performance improvement of the strapdown inertial support and navigation system precision. 2011 IEEE.   Distribution of gyroscope accuracy parameters for E-O stabilization platform (EI CONFERENCE) 会议论文 2011 International Conference on Electric Information and Control Engineering, ICEICE 2011, April 15, 2011 - April 17, 2011, Wuhan, China Jiang H.; Jia H.; Wei Q.; Zhang X. 收藏  |  浏览/下载：18/0  |  提交时间：2013/03/25 E-O stabilization platform performance is partly decided by gyroscope precision  so it is important to choose a gyroscope with proper accuracy for an E-O stabilization platform. Based on the method of using a gyroscope in practice  gyroscope error model is established. With the gyroscope error model gyroscope accuracy parameters  that is bias repeatability  bias stability  scale factor  scale factor nonlinearity  output noise and bandwidth  are separately analyzed. According to the concretely required performance indices for an E-O platform  means of distribution of gyroscope accuracy parameters is proposed. A MEMS gyroscope is tested to get the parameters. Bias stability of the gyroscope is 0.08 /s while the bandwidth is 60 Hz. Output noise both at zero input and at nonzero input is analyzed by means of PSD to get the result that nonzero output noise is higher than zero output noise. Frequency response result of the gyroscope is dealt by means of correlation analysis. With all the tested result and the method of distribution of gyroscope accuracy parameters  it is clear that how the gyroscope errors works in an E-O servo system. The principle of distribution of gyroscope accuracy parameters is helpful for choosing appropriate gyroscope for an E-O platform. 2011 IEEE.   Design and analysis of auto-focus assembly for spaceborne remote sensing camera (EI CONFERENCE) 会议论文 2011 International Conference on Electronics, Communications and Control, ICECC 2011, September 9, 2011 - September 11, 2011, Ningbo, China Chen W.; Ding Y.; Hui S.; Gao X. 收藏  |  浏览/下载：22/0  |  提交时间：2013/03/25 Spaceborne remote sensing camera may be out of focus when the environment and photographic distance changes. In order to get higher ground sampled distance for the camera  based on the experience gained from the development of a remote sensing camera  working principle of auto-focus assembly control system was discussed. Time of waveform extraction was reduced. It sets force an auto-focus assembly that uses cam and line guide rail in order to move the lens group. The motion error of the auto-focus assembly was difficult to be eliminated and would affect on the focusing accuracy of the spaceborne remote sensing camera directly. So it was analyzed at both ends of the focusing structure. The CCD detector can keep stable when the remote sensing camera is imaging. The motion error was tested to verify the validity of the simulation result and it is less than 0.01mm. Its accuracy meets using demand. The focusing method of moving focal plane is suitable for spaceborne remote sensing camera. 2011 IEEE.   Study of the neural network constitutive models for turfy soil with different decomposition degree (EI CONFERENCE) 会议论文 2011 2nd International Conference on Mechanic Automation and Control Engineering, MACE 2011, July 15, 2011 - July 17, 2011, Inner Mongolia, China Lv Y.; Nie L.; Xu K. 收藏  |  浏览/下载：16/0  |  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.   Research on the identification for a nonlinear system (EI CONFERENCE) 会议论文 International Conference on Optical, Electronic Materials and Applications 2011, OEMA 2011, March 4, 2011 - March 6, 2011, Chongqing, China Lv S.; Liu J.; Jia P. 收藏  |  浏览/下载：24/0  |  提交时间：2013/03/25 The characteristic of the drift error of inertial platform is a high-order nonlinear dynamic system  using the neural networks' abilities of universal approximation of differentiable trajectory and capturing system dynamic information  this paper presents the drift error identifying project of inertial platform based on Elman networks structure. First  the drift error model of inertial platform is established  after selecting the input and output for network  momentum and alterable speed algorithm is used to speed up the network convergence. On the basis of the algorithm  the extended nonlinear node function in the hidden network does not only improve the learning speed of network  but also satisfies the need of accuracy on system identification. Through the drift error data measured on inertial platform  the training result shows that the scheme achieves satisfied identification results. (2011) Trans Tech Publications.   Application of particulate reinforced aluminum matrix composite in airborne photoelectric turret (EI CONFERENCE) 会议论文 2011 International Conference on Electric Information and Control Engineering, ICEICE 2011, April 15, 2011 - April 17, 2011, Wuhan, China Cheng Z.-F.; Zhang B.; Dai M.; Wang P.; Huang M. 收藏  |  浏览/下载：16/0  |  提交时间：2013/03/25 In order to design and manufacture more excellent airborne photoelectric stable turret  modulus of elasticity of 213 GPa and thermal expansion coefficient of 7.9106/K. The frame has decreased the maximum deformation by by 60% and increased the fundamental frequency by 65% as compared with those of aluminum alloy materials  a new type of aeronautical material-particulate reinforced aluminum matrix composite (SiC/Al composite) is investigated. Several crucial technologies  respectively as shown by finite element analysis results. Those are confirmed by vibration test furthermore. Therefore  such as pressureless infiltration technology  a significant lightening effect is achieved and the thermal control load is also reduced. The test result indicates that the stable accuracy of the system achieves 19.8rad and the optical-axis parallelism of pay load is 0.1mrad. The research applies the SiC/Al composites to airborne photoelectric platforms  interface reaction controls and plate's welding are systematically studied. Then  which makes a effective exploration for the new aeronautical material's application. 2011 IEEE.  using SiC/Al composites  the airborne photoelectric stable turret frame is successfully prepared in density of 2.94 g/ cm3   Study on image real-time interpretation based on particle filter (EI CONFERENCE) 会议论文 2011 International Conference on Mechatronic Science, Electric Engineering and Computer, MEC 2011, August 19, 2011 - August 22, 2011, Jilin, China Wang Z.-Q.; Liu S.-J.; Geng T.-W.; Shen C.-W.; Yu S.-B. 收藏  |  浏览/下载：23/0  |  提交时间：2013/03/25 In order to satisfy to the real-time requirement of image interpretation system in photoelectric measurement equipments  a kind of hardware acceleration system with MIMD distributed multi-processor architecture based on SOPC technology is designed. The particle filter algorithm is proposed to process image interpretation for state estimation problem of nonlinear and non-Gaussian system. This algorithm does not involve conventional linearization transform  and has approximated the posterior probability density by a set of discrete particles. Therefore the approximate optimum result is educed. It has a high accuracy and a rapid convergence. Experimental results show that the algorithm be adequate to real time  accuracy and robustness  meets the requirement of image interpretation and possesses practical significance for engineering applications. 2011 IEEE.