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	High-Precision Attitude Post-Processing and Initial Verification for the ZY-3 Satellite 期刊论文 OAI收割 REMOTE SENSING, 2015, 卷号: 7, 期号: 1, 页码: 195-210 作者: Tang, Xinming; Xie, Junfeng; Wang, Xiao; Jiang, Wanshou 收藏 \| 浏览/下载：76/0 \| 提交时间：2016/04/20 attitude accuracy star tracker/gyro post-processing geometric accuracy
	Adaptive control at launching using three loop autopilot (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: Zhang Y. 收藏 \| 浏览/下载：28/0 \| 提交时间：2013/03/25 In order to guarantee the precise initial flight trajectory control the missile disturbance of large disturbance torque three loop adaptive autopilot was researched. The characteristics of the projectile and three loop autopilot instruction formation characteristics were analysed. From equivalent pitching angle of lateral acceleration feedback loop combined with the instruction of generalized error autopilot structure was simplified and three loop autopilot adaptive control law and stability were designed. The test data show that when disturbance torque was 600Nm the attitude angle generalized error was -4.4. In the time lasted about 15s late trajectory accuracy was within 1.0.Three loop autopilot adaptive control law was able to control the disturbance of initial trajectory and adapt to dynamic characteristics changes control system stability. It was the initial trajectory accurate solution method of flight. 2011 IEEE.
	Three-sample rotation vector algorithm with angular rate input (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: Zhang Y. 收藏 \| 浏览/下载：25/0 \| 提交时间：2013/03/25 In order to research the attitude algorithm with angular rate input under the conical motion a optimal threesample rotation vector algorithm based on single-step Newton backward interpolation is proposed. Using the principle of limited rigid body rotation and the characteristic of angular rate input three-sample rotation vector algorithm is derivated. To minimum attitude errors three-sample rotation vector algorithm is optimized. Three angular rate extraction methods of singlestep entire sample recursion multi-step entire sample and singlestep Newton backward interpolation are proposed. Under the condition of conical motion with semi-cone angle 3 and angular frequency 2rad/s simulation is done. The simulation results show that single-step Newton backward interpolation is superior to the other two methods and its maximum error peak is 0.01 error drift rate is 0.036/h. Experiments in three-axis flying turntable with the same parameters are carried out and the results show that error drift rates of three-channels are less than those of traditional quaternion which are 13.53% 12.08% and 23.68% lower respectively. It also verified that the new algorithm can perform a high accuracy under the conical motion. 2011 IEEE.
	A 3-axis simulator for spacecraft attitude control research (EI CONFERENCE) 会议论文 OAI收割 2010 IEEE International Conference on Information and Automation, ICIA 2010, June 20, 2010 - June 23, 2010, Harbin, Heilongjiang, China 作者: Dai L. 收藏 \| 浏览/下载：34/0 \| 提交时间：2013/03/25 This article presents the details of a new 3-axis simulator for spacecraft attitude control research and simulation. The air bearing allows the test bed to rotate about three axes with tiny friction. The attitude determination system consists of three fibre optical gyros an inclinometer and a magnetometer. The actuator of the system consists of three reaction flywheels and four control moment gyros (CMG). Mathematical models of the sensors and actuators are given to help algorithm design. An extended Kalman filter was designed to provide attitude information for controller. Mathematical simulation results prove the attitude determination system can achieve high precision. A coulomb friction model of reaction wheels is given with experimental results. A friction compensation algorithm was developed to raise the pointing accuracy of the control system. The article also describes the details of the hardware structure. A PD stabilizing controller is implemented to test the validation of the whole control system at last. 2010 IEEE.
	Design of ground-based physical simulation system for satellite-borne TDI-CCD dynamic imaging (EI CONFERENCE) 会议论文 OAI收割 Optoelectronic Imaging and Multimedia Technology, October 18, 2010 - October 20, 2010, Beijing, China 作者: Zhang L.; Zhang L.; Sun Z. 收藏 \| 浏览/下载：27/0 \| 提交时间：2013/03/25 As we know the existence of image motion has a bad effect on the image quality of satellite-borne TDI CCD camera. Although many theories on image motion are proposed to cope with this problem few simulations are done to justify the proposed theories on ground. And thus in this paper a ground-based physical simulation system for TDI CCD imaging is developed and specified which consists of a physical simulation subsystem for precise satellite attitude control based on a 3-axis air bearing table and an imaging and simulation subsystem utilizing area-array CCD to simulate TDI CCD. The designed system could realize not only a precise simulation of satellite attitude control whose point accuracy is above 0.1 and steady accuracy above 0.01/s but also an imaging simulation of 16-stage TDI CCD with 0.1s its integration time. This paper also gives a mathematical model of image motion of this system analogous with satellite-borne TDI CCD and detailed descriptions on the principle utilizing area-array CCD to simulate TDI CCD. It is shown that experiment results are in accordance with mathematical simulation and that the image quality deteriorate seriously when the correspondence between the image velocity and signal charges transfer velocity is broken out which suggest not only the validity of the system design but also the validity of the proposed image motion theory of TDI CCD. 2010 SPIE.
	High accuracy star image locating and imaging calibration for star sensor technology (EI CONFERENCE) 会议论文 OAI收割 6th International Symposium on Precision Engineering Measurements and Instrumentation, August 8, 2010 - August 11, 2010, Hangzhou, China 作者: Wang Y.; Wang Y.; Wang Y.; Wang Y.; Wang Y. 收藏 \| 浏览/下载：25/0 \| 提交时间：2013/03/25 Today aircraft attitude measurement technology plays an important role in an aircraft system because it can provide orientation for aircraft in action. Lately star sensor technology used in aircraft attitude measurement has become more and more popular because of its high accuracy light weight without attitude accumulation errors and other advantages. There are three main steps for star sensor to measure aircraft attitude star image locating star identification and attitude tracking. The latter two steps are based on the accuracy of star image locating. So it's critical to make efforts to advance the accuracy of star image locating. Some imaging errors such as spherical aberration or coma aberration also have negative effect on the accuracy of star image locating of which the effect is necessarily reduced as well. At the beginning of this article the structure of star sensor hardware is introduced. Secondly three methods for star image locating are described specifically which are traditional centroid method Gauss quadric fitting method and improved Gauss quadric fitting method. Subsequently an imaging calibration method is described for the purpose of reducing the effect of imaging errors. Finally the experiment shows that the accuracy of the star sensor is 2-arc-second. 2010 SPIE.
	Design of high precision star image locating method used in star sensor technology (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: Sun H.; Wang Y.; Wang Y.; Wang Y.; Wang Y. 收藏 \| 浏览/下载：57/0 \| 提交时间：2013/03/25 Nowadays star sensor technology used in aircraft attitude measurement has become more and more popular for its high precision light weight without attitude accumulation errors and other advantages. In order to enhance the accuracy of star sensor it is critical to make efforts to promote the precision of star image locating. High precision star image locating method mentioned in this article includes two aspects. One is sub-pixel dividing algorithm used to acquire the coordinate of stars. The other one is imaging calibration method used to weaken the effect caused by imaging distortion. This method is finally realized in some type of star sensor system. Then an experiment is designed to verify the precision of the method. The result of the experiment shows that the precision of the method is 2" in the experimental environment. 2010 IEEE.
	Design and DSP implementation of star image acquisition and Star point fast acquiring tracking (EI CONFERENCE) 会议论文 OAI收割 2nd International Symposium on Advanced Optical Manufacturing and Testing Technologies: Optical Test and Measurement Technology and Equipment, November 2, 2005 - November 5, 2005, Zian, China 作者: Wang X.; Wang X.; Wang X. 收藏 \| 浏览/下载：31/0 \| 提交时间：2013/03/25 Star sensor is a special high accuracy photoelectric sensor. Attitude acquisition time is an important function index of star sensor. In this paper the design target is to acquire 10 samples per second dynamic performance. On the basis of analyzing CCD signals timing and star image processing a new design and a special parallel architecture for improving star image processing are presented in this paper. In the design the operation moving the data in expanded windows including the star to the on-chip memory of DSP is arranged in the invalid period of CCD frame signal. During the CCD saving the star image to memory DSP processes the data in the on-chip memory. This parallelism greatly improves the efficiency of processing. The scheme proposed here results in enormous savings of memory normally required. In the scheme DSP HOLD mode and CPLD technology are used to make a shared memory between CCD and DSP. The efficiency of processing is discussed in numerical tests. Only in 3.5ms is acquired the five lightest stars in the star acquisition stage. In 43us the data in five expanded windows including stars are moved into the internal memory of DSP and in 1.6ms five star coordinates are achieved in the star tracking stage.
	CMOS APS imaging system application in star tracker (EI CONFERENCE) 会议论文 OAI收割 Advanced Materials and Devices for Sensing and Imaging II, November 8, 2004 - November 10, 2004, Beijing, China 作者: Li J.; Liu Y.; Liu Y.; Liu Y.; Liu J. 收藏 \| 浏览/下载：59/0 \| 提交时间：2013/03/25 Small satellites are capable of performing space explore missions that require accurate attitude determination and control. However low weight size power and cost requirements limit the types of attitude sensor of small craft such as CCD are not practical for small satellites. CMOS APS is a good substitute for attitude sensors of small craft. Some of the technical advantages of CMOS APS are no blooming single power low power consumption small size and little support circuitry direct digital output simple to system design in particular radiation-hard characteristic compare with CCD. This paper discusses the application probability of CMOS APS in star tracker for small satellites further more a prototype ground-based star camera based on STAR250 CMOS image sensor has been built. In order to extract stars positions coordinates subpixel accuracy centroiding algorithm has been developed and tested on some ground-based images. Moreover the camera system star sensitivity and noise model are analyzed and the system accuracy is been evaluated. Experimental results indicate that a star camera based on CMOS APS is a viable practical attitude sensor appropriate for space small satellites.