中国科学院机构知识库网格系统: 检索

The design of space scanning mirror control system based on optimal tracking controller (EI CONFERENCE) 会议论文 OAI收割
2012 International Conference on Electrical Insulating Materials and Electrical Engineering, EIMEE 2012, May 25, 2012 - May 27, 2012, Shenyang, Liaoning, China
作者: Zhang P.

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Control system of space scanning mirror has high requirement of scanning accuracy. The use of optimal tracking controller simulation experiment of the control system based on optimal tracking controller is carried out. The simulation result instead of traditional PID controller the control system based on optimal tracking controller is designed in comparison with the system based on a PID controller can effectively improve the scanning accuracy of space scanning mirror control system. State space model of the control system is established shows that the scanning mirror control system using optimal tracking controller instead of PID controller has higher scanning accuracy and faster response. (2012) Trans Tech Publications Switzerland.

Study on the servo system of large telescope based on the internal model pid control strategy (EI CONFERENCE) 会议论文 OAI收割
IEEE 2011 10th International Conference on Electronic Measurement and Instruments, ICEMI 2011, August 16, 2011 - August 18, 2011, Chengdu, China
Li H.

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This paper developed the internal model PID control for large telescope control system considerations in more parameters adjustment in servo control loop at present. The large electro-optic telescope system belongs to a big inertia system. This simplifies the debug process the feasibility and robustability are also verified by the analyses and simulation results that satisfy the high precision demand. The practicability of this algorithm is verified in an actual project that only two parameters need adjusted. The application shows that this system runs stably with high accuracy. The technology and methods adopted in the system are practical and worthy of using abroad. 2011 IEEE.

Research on computer control strategy for optical electric tracking system (EI CONFERENCE) 会议论文 OAI收割
2011 IEEE International Conference on Mechatronics and Automation, ICMA 2011, August 7, 2011 - August 10, 2011, Beijing, China
作者: Li M.

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In this paper mathematic model and computer control strategy for optical electrical tracking system have been researched and discussed. First the system's structure and its work process have been analyzed. Second according to the system's moving law the system's mathematic model has been built. As to the computer control strategy trigger guiding two closed loop PID control method as well as compound control method have been applied to satisfy the tracking accuracy. Third we apply the bilinear transformation to get the digital system and the sample time is 800Hz. The simulation results indicate that the maximum tracking error can be limited to less than 0.5 and the regulator time can be 0.04s. Then the control project resonance frequency should be more than 200Hz and the sample frequency should be more than 400Hz to meet the control accuracy requirement. So we can conclude that the system indexes such as swiftness high accuracy as long as real time have been satisfied. And the requirement of mechanical property has been present which is very useful to mechanical working. 2011 IEEE.

The design of acquisition circuit for grating digital signal based on FPGA (EI CONFERENCE) 会议论文 OAI收割
2010 3rd International Conference on Advanced Computer Theory and Engineering, ICACTE 2010, August 20, 2010 - August 22, 2010, Chengdu, China
作者: Wang W.-G.

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In order to resolve the poor suppression capability of noise and fitter interference existing in grating encoder high-rate subdivision and the poor accuracy of kam-to counting circuit the results show that the design method will help improve the controlled object of measurement precision and control accuracy. 2010 IEEE. we design a circuit based on FPGA to realize multiplier kam and filter for the output of two-way orthogonal signal generated by Incremental Optical Encoder. The system is mainly divided into three modules such as filtering multiplier kam-to and counting. The main function of filter circuit is to eliminate the jitter and noise interference existing in the quadrate encoder signals. Kam-to multiplier circuit can accurately judge the full cycle and half-cycle of incremental encoder at the same time can make fourfold multiplier. Counting circuit can use IP cores owned by Quartus II which is not restricted on the median. At last timing simulation based on Modelsim carried on the three modules

A new method of measuring lead screw with dual-frequency laser interference (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: Qi X.-D.

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A new optical structure of measuring lead screw with dual-frequency laser interferometer is proposed and a formula used quickly correcting Abbe error is deduced in this paper. In the process of testing lead screw Abbe error in the measured data can be real time compensated so that the measurement system which doesn't meet Abbe principle can achieve high measurement accuracy. In addition this method can also eliminate measurement error induced by axial movement of the measured lead screw. The experimental result shows that of the maximum residual error is only 0.48m within 300mm stroke after the maximum Abbe error 1.39m is corrected. This method effectively improves the measurement accuracy of lead screw. 2010 IEEE.

Phase-laser ranging system based on digital signal processing for optoelectronics theodolite application (EI CONFERENCE) 会议论文 OAI收割
2010 3rd International Conference on Advanced Computer Theory and Engineering, ICACTE 2010, August 20, 2010 - August 22, 2010, Chengdu, China
作者: Liu Y.-S.

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In order to meet requirement of high accurate ranging the laser ranging system is designed for optoelectronics theodolite application by this paper based on digital signal processing. Variable modulating method is used to solve the antinomy between the measuring range and accuracy. Frequency mixing is adopted to reduce the frequency of the signal which can lower the requirement for hardware. The high ranging accuracy is achieved by way of Fast Fourior Transform (FFT) using digital signal processor and error correcting factor. Experiment results indicate that using digital signal processing method can reduce the influence of surroundings and hardware system and obtain high ranging accuracy. 2010 IEEE.

Influence of spatial temperature distribution on high accuracy interferometric metrology (EI CONFERENCE) 会议论文 OAI收割
5th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Optical Test and Measurement Technology and Equipment, April 26, 2010 - April 29, 2010, Dalian, China
作者: Yang H.; Zhang J.; Zhang J.

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We calculate the influence of temperature change on the refractive index of air establish a model of air temperature distribution and analyze the effect of different temperature distribution on the high accuracy interferometric metrology. First a revised Edlen formula is employed to acquire the relation between temperature and refractive index of air followed by introducing the fixed temperature gradient distribution among the spatial grid within the optical cavity between the reference flat and the test flat of the Fizeau interferometer accompanied by a temperature change random function within each grid. Finally all the rays through the air layer with different incident angles are traced by Matlab program in order to obtain the final output position angle and OPD for each ray. The influence of different temperature distribution and the length of the optical cavity in on the testing accuracy can be analyzed through the RMS value that results from repeatable rays tracing. As a result the horizontal distribution (vertical to optical axis) has a large effect on the testing accuracy. Thus to realize the high accuracy figure metrology the horizontal distribution of temperature must be rigorously controlled as well as to shorten the length of the optical cavity to a large extent. The results from our simulation are of great significant for the accuracy analysis of interferometric testing and the research of manufacturing a interferometer. 2010 Copyright SPIE - The International Society for Optical Engineering.

Study on dynamic imaging on TDI CCD optical remote sensor of push-broom technology (EI CONFERENCE) 会议论文 OAI收割
5th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Optical Test and Measurement Technology and Equipment, April 26, 2010 - April 29, 2010, Dalian, China
作者: Liu L.; Ren J.-Y.; Liu L.; Gao M.-H.

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A set special detecting system is proposed based on TDICCD push-broom technology applying in dynamic imaging detecting experiment of space optics remote sensor. In the system In the course of detecting push-broom movement of the satellite is simulated through using double supporting U structure precision rotary platform with remote sensor by angular speed 0.555/s regard Nyquist frequency target as detecting aim within the range of 5 and control precision on steady speed achieves 0.3% in order to solve matching uncertainty between the CCD pixel and the vertical target strip image when the remote sensor does push-broom make matching simplify enhance the measurement result the accuracy. So the tolerance a/n arithmetic progression gap target strip is joined in each group of rectangular vertical group target strip. The remote sensor obtains in vertical the level and 45 the direction 0 fields of view 0.86 the field of view Nyquist frequency target strip image after detected a group target strip which can precision matching to TDICCD pixel at least can be obtained through analysis and dealing with 0.86 field of view's target strip image. The experiment not only verifies the detecting system's feasibility but simultaneously verifies whether to have the high quality dynamic imaging quality when TDICCD push-broom technology is adopted on the remote sensor developed. 2010 Copyright SPIE - The International Society for Optical Engineering.

Three-dimensional angle measurement based on auto-collimation and moire fringe (EI CONFERENCE) 会议论文 OAI收割
2008 International Conference on Optical Instruments and Technology: Optoelectronic Measurement Technology and Applications, November 16, 2008 - November 19, 2008, Beijing, China
Cai S.; Liang S.; Qiao Y.-F.

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A method for small three-dimensional (3D) angle measurement based on auto-collimation and moire fringe is proposed and analyzed. A right-angle prism is used as the indicator of angle change. The inclined plane indicates the pitch and yaw angles and roll angle in indicated by the rib which is the intersection of two right-angle sides. Pitch and yaw angles measurement are implemented by auto-collimation based on reticule and roll angle measurement is measured based on moire fringe. Roll angle measurement is separated from pitch and yaw by using two light sources with different frequencies. Any small change of pitch and roll angles will induce the shift of the reticule image after reflecting by inclined plane. And any small roll angle will induce a change in moire fringe width that is generated by scale grating image which is reflected by the prism and index grating. The math model of this method is built up and error analysis is presented. The theoretical calculation results show that the proposed method is feasible and can achieve high accuracy. 2009 SPIE.

Autofocusing technique based on image processing for remote-sensing camera (EI CONFERENCE) 会议论文 OAI收割
International Symposium on Photoelectronic Detection and Imaging 2007 - Image Processing, September 9, 2007 - September 12, 2007, Beijing, China
作者: Wang X.; Xu S.-Y.; Wang X.; Wang X.

收藏 | 浏览/下载：22/0 | 提交时间：2013/03/25

The key to the auto-focusing technique based on image processing is the selection of focus measure reflecting image definition. Usually the measures derived are on the premise of the images acquired with the same scene. As for the remote-sensing camera working in linear CCD push-broom imaging mode the premise doesn't exist because the scenes shot are different at any moment which brings about difficulties to the selection of the focus measure. To evaluate the image definition the focus measure based on blur estimation for rough adjustment is proposed to estimate the focused position by only two different lens positions which greatly saves the auto-focusing time. Another evaluation function based on edge sharpness is developed to find best imaging position in the narrow range. Simulations show that the combination of the two measures has the advantages of rapid reaction and high accuracy.