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Inverse Calculation and Regularization Process for the Solar Aspect System(SAS) of HXI Payload on ASO-S Spacecraft

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Research in Astronomy and Astrophysics 2024年第4期24卷 13-34页

作者： Ji-Rui Yu Ping Ruan Yang Su Ying-Hong He Jin-You Tao Zhe Zhang Song Guo Bin Xue Jian-Feng Yang Xi'an Institute of Optics and precision mechanics of Chinese Academy of Sciences Xi'an 710119China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory of Dark Matter and Space Astronomy Purple Mountain ObservatoryChinese Academy of SciencesNanjing 20034China School ofAstronomy and Space Science Universityof Science and Technology of ChinaHefei 230026China

For the ASO-S/HXI payload, the accuracy of the flare reconstruction is reliant on important factors such as the alignment of the dual grating and the precise measurement of observation orientation. To guarantee optimal functionality of the instrument throughout its life cycle, the Solar Aspect System (SAS) is imperative to ensure that measurements are accurate and reliable. This is achieved by capturing the target motion and utilizing a physical model-based inversion algorithm. However, the SAS optical system’s inversion model is a typical ill-posed inverse problem due to its optical parameters, which results in small target sampling errors triggering unacceptable shifts in the solution. To enhance inversion accuracy and make it more robust against observation errors, we suggest dividing the inversion operation into two stages based on the SAS spot motion model. First, the as-rigid-aspossible (ARAP) transformation algorithm calculates the relative rotations and an intermediate variable between the substrates. Second, we solve an inversion linear equation for the relative translation of the substrates, the offset of the optical axes, and the observation orientation. To address the ill-posed challenge, the Tikhonov method grounded on the discrepancy criterion and the maximum a posteriori (MAP) method founded on the Bayesian framework are utilized. The simulation results exhibit that the ARAP method achieves a solution with a rotational error of roughly±3 5 (1/2-quantile);both regularization techniques are successful in enhancing the stability of the solution, the variance of error in the MAP method is even smaller—it achieves a translational error of approximately±18μm (1/2-quantile) in comparison to the Tikhonov method’s error of around±24μm (1/2-quantile). Furthermore, the SAS practical application data indicates the method’s usability in this study. Lastly, this paper discusses the intrinsic interconnections between the regularization methods.

关键词： methods:data analysis Sun:flares Sun:X-rays gamma rays

从中国首台紫外-可见光高光谱卫星仪器反演得到的高空间分辨率臭氧廓线

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Engineering 2024年第1期32卷 106-115页

作者： Fei Zhao Cheng Liu Qihou Hu Congzi Xia Chengxin Zhang Wenjing Su Department of precision Machinery and precision instrumentation University of Science and Technology of ChinaHefei 230026China Center for Excellence in Regional Atmospheric Environment Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China Key Lab of Environmental Optics and Technology Anhui Institute of Optics and Fine MechanicsChinese Academy of SciencesHefei 230031China Key Laboratory of precision Scientific instrumentation of Anhui Higher Education Institutes University of Science and Technology of ChinaHefei 230026China Anhui Province Key Laboratory of Polar Environment and Global Change University of Science and Technology of ChinaHefei 230026China Greater Bay Area(GBA)Branch of Aerospace Information Research Institute Chinese Academy of SciencesGuangzhou 510700China Department of Environmental Science and Engineering University of Science and Technology of ChinaHefei 230026China

Understanding the vertical distribution of ozone is crucial when assessing both its horizontal and vertical transport,as well as when analyzing the physical and chemical properties of the *** of the most effective ways to obtain high spatial resolution ozone profiles is through satellite *** Environmental Trace Gases Monitoring instrument(EMI)deployed on the Gaofen-5 satellite is the first Chinese ultraviolet-visible hyperspectral ***,retrieving ozone profiles using backscattered radiance values measured by the EMI is challenging due to unavailable measurement errors and a low signal-to-noise *** algorithm developed for the Tropospheric Monitoring instrument did not allow us to retrieve 87%of the EMI ***,we developed an algorithm specific to the characteristics of the *** fitting residuals are smaller than 0.3%in most *** retrieved ozone profiles were in good agreement with ozonesonde data,with maximum mean biases of 20%at five latitude *** applying EMI averaging kernels to the ozonesonde profiles,the integrated stratospheric column ozone and tropospheric column ozone also showed excellent agreement with ozonesonde data,The lower layers(0-7.5 km)of the EMI ozone profiles reflected the seasonal variation in surface ozone derived from the China National Environmental Monitoring Center(CNEMC).However,the upper layers(9.7-16.7 km)of the ozone profiles show different trends,with the ozone peak occurring at an altitude of 9.7-16.7 km in March,2019.A stratospheric intrusion event in central China from August 11 to 15,2019,is captured using the EMI ozone profiles,potential vorticity data,and relative humidity *** increase in the CNEMC ozone co ncentration showed that downward transport enhanced surface ozone pollution.

关键词： Ozone profiles EMI Soft calibration Floor noise correction Stratospheric ozone intrusion

Dark-field line confocal imaging with point confocality and extended line field for bulk defects detection

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Chinese Optics Letters 2023年第4期21卷 26-30页

作者：董敬涛张腾达杨蕾张育中卢荣胜谢兴龙 Anhui Province Key Laboratory of Measuring Theory and precision instrument School of Instrument Science and Opto-electronic EngineeringHefei University of TechnologyHefei 230009China Key Laboratory of High Power Laser and Physics Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800China

Fabrication of high-quality optics puts a strong demand on high-throughput detection of macroscopic bulk defects in optical components.A dark-field line confocal imaging method is proposed with two distinct advantages:(ⅰ)a point-to-line confocal scheme formed by a columnar elliptical mirror and an optical fiber bundle breaks through the constraint on light collection angle and field of view in the traditional line confocal microscopy using an objective,allowing for an extended confocal line field of more than 100 mm while maintaining a light collection angle of 27°;(ⅱ)the bulk defects are independently illuminated as a function of time to eliminate the cross talk in the direction of the confocal slit,thus preserving point confocality and showing the optical section thicknesses to be 162μm in the axial direction,and 19 and 22μm in the orthogonal transverse *** experimental results verify that the method has a minimum detectable bulk defect of less than 5μm and an imaging efficiency of 400 mm2/*** method shows great potential in high-throughput and highsensitivity bulk defects detection.

关键词： line confocal imaging dark-field imaging bulk defects detection

Error correction method of 6-HTRT parallel mechanics

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Journal of Harbin Institute of Technology(New Series) 2007年第2期14卷 193-196页

作者：张秀峰季林红 College of Automation Harbin Engineering University dept. of precision instrument and mechanics Tsinghua University

The method of error correction is one of key techniques of parallel robot. A new method of end error correction of 6-HTRT parallel robot is presented for engineering and researching on correlative theory of 6-HTRT parallel robot. The method need calculate many kinematics equations of parallel robot such as position back solution, velocity Jacobin, position forward solution and error Jacobin. New methods presented for solving these questions are simpler and fitter for programming and calculating, because former methods are too complex to use in engineering. These questions may be solved by iterative method of numerical value which has fast velocity of calculating. These new methods may be used in other mechanism of parallel robot too, and so have wider using value. The experimental results demonstrate that the system may satisfy entirely high technical request and fit for engineering in new measures.

关键词： 6-HTRT并联机器人误差校正方法定位误差运动精度

Pit dept. and Width Modulation Multilevel Run-Length Limited Read-Only Optical Storage

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Chinese Physics Letters 2006年第6期23卷 1504-1506页

作者：宋洁裴京徐端颐熊剑平陈垦潘龙法 Department of precision instrument and mechanics Tsinghua University Beijing 100084

When the techniques of integrating the variation of the conventional DVD,the high-density multilevel run-length pit dept. and width simultaneously are adopted to limited read-only optical storage method is achieved. The dynamic range of readout signal is greatly enlarged in comparison with keeping one parameter varied, and the recording levels number can be obviously increased. The discs can be manufactured using standard photoresist mastering and replication techniques with great compatibility to conventional binary read-only discs. Experimental results show that eight-level read-only optical disc can be realized and the capacity can be increased to 20 GB.

关键词： DISCS

Brightness Independent 4-Star Matching Algorithm for Lost-in-Space 3-Axis Attitude Acquisition

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Tsinghua Science and Technology 2006年第5期11卷 543-548页

作者：董瑛邢飞尤政 Department of precision instrument and mechanics Tsinghua University

A star identification algorithm was developed for a charge-coupled device （CCD） or complementary metal-oxide-semiconductor （CMOS） autonomous star tracker to acquire 3-axis attitude information for a lost-in-space spacecraft. The algorithm took advantage of an efficient on-board database and an original “4- star matching” pattern recognition strategy to achieve fast and reliable star identification. The on-board database was composed of a brightness independent guide star catalog （mission catalog） and a K-vector star pair catalog. The star pattern recognition method involved direct location of star pair candidates and a sim- ple array matching procedure. Tests of the algorithm with a CMOS active pixel sensor （APS） star tracker result in a 99.9% success rate for star identification for lost-in-space 3-axis attitude acquisition when the angular measurement accuracy of the star tracker is at least 0.01°. The brightness independent algorithm requires relatively higher measurement accuracy of the star apparent positions that can be easily achieved by CCD or CMOS sensors along with subpixel centroiding techniques.

关键词： star identification attitude acquisition star tracker lost-in-space active pixel sensor (APS)

Study on Technique of Surface Plasmon Resonance Imaging Sensing for Biomolecular Interaction

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稀有金属材料与工程 2006年第A3期35卷 483-487页

作者： Ding Xiang Rong Xiaofeng Deng Yan Yu Xinglong dept. of precision instrument Tsinghua University Beijing 100084 China

High resolution of surface plasmon resonance (SPR) detection is of vital *** biosensing system resolution is determined by intrinsic sensitivity of biochip and light signal acquisition *** this article,different signal acquisition system resolutions on photodetector were analyzed based on light intensity and phase *** shows that charge coupled device (CCD) with larger numbers of pixels is potential to achieve higher detection resolution.A 64 pixel line array CCD and a 12 bit ADC can achieve resolution of 10^(-7) refractive index unit (RIU).In array detection mode,increasing of detection throughput is at the cost of decreasing system *** analysis indicates that,if noise is taken into account,phase modulation methods are capable of providing better noise reduction performance than intensity methods.

关键词： SPR biosensing intensity detection phase detection resolution

A Novel Tunable Dual-frequency Laser with Large Frequency Difference

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Chinese Journal of Lasers 2002年第4期11卷 12-15页

作者：黄春宁郭辉李岩朱钧张书练 dept. of precision instruments Tsinghua University The State Key Laboratory of Precision Measurement Technology and Instrument 北京 100084 dept. of precision instruments Tsinghua University The State Key Laboratory of Precision Measurement Technology and Instrument 上海 100084

This paper proposed a novel tunable dual frequency laser with large frequency difference,which used LD to pump the Nd∶YAG microchip in the end surface and put the liquid pressure on the radial direction of the crystal by a pressure transporting thin film. As a result of the stress birefringence, there was a mode splitting phenomenon of the microchip laser longitudinal mode. Both theoretical analysis and experiments indicated that there is a directly proportional relation between the frequency difference and the pressure, so the tunable frequency difference could be obtained when the pressure was changed. A large frequency difference of about 3.4 GHz with linear tunable relation was achieved in the experiment,so it can be a practical light source for the absolute distance interferometry.

关键词： large frequency difference tunable dual frequency LD pumped Nd∶YAG laser

An Application of Optimal Preview Control in Terrain Following System

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Journal of Systems Engineering and Electronics 2002年第1期13卷 21-26页

作者： Li Dongmei dept. of precision instrument and mechanics, Tsinghua University, Beijing 100084, P.R.China Zhou Di, Hu Zhenkun & Hu Hengzhang dept. of Control Science and Engineering, Harbin Institute of Technology, Harbin 150001, P.R.China dept. of precision instrument and mechanics Tsinghua University Beijing 100084 P. R. China dept. of Control Science and Engineering Harbin Institute of Technology Harbin 150001 P. R. China

An optimal preview method is applied to the design of terrain following controller for cruise missile. In this method, tracking errors and control increments are both considered in the quadratic cost function. Integrating the general optimal servo system with a preview feedforward compensation that feeds forward future command and future disturbance produces an optimal preview servo system. In the terrain following system, the flight altitude of the cruise missile is a command signal, and its future information can be known apriori. Hence, we have designed a terrain following controller with a basic state feedback and a feedforward compensation for future altitude information. Simulation results show that the performance of the terrain following system with such an optimal preview controller has been improved dramatically.

关键词： Cruise missile Terrain following Preview control Optimal control Feedforward compensation.