中国科学院机构知识库网格系统: 检索

A novel miniature absolute metal rotary encoder based on Single-track Periodic Gray Code (EI CONFERENCE) 会议论文 OAI收割
2012 2nd International Conference on Instrumentation and Measurement, Computer, Communication and Control, IMCCC 2012, December 8, 2012 - December 10, 2012, Harbin, Heilongjiang, China
作者: Sun Y.; Yang S.-W.; Sun Y.; Wan Q.-H.

收藏 | 浏览/下载：28/0 | 提交时间：2013/03/25

In order to improve the resolution and enhance the impact resistance and vibration resistance of encoders a novel absolute metal rotary encoder based on Single-track Periodic Gray Code is presented. The configuration and working principle of the encoder is introduced and then the metal code disc which can realize full scale absolute encoding on one single track and its corresponding metal slit disc are proposed. Finally the data acquisition and processing system based on FPGA of encoder is presented. The resolution of the encoder can reach 5.27through electronic subdivision and calibration between the precision code and the coarse code with its volume only 4840mm. The encoder has some advantages such as small volume low cost high resolution and strong impact resistance. 2012 IEEE.

Design of motion adjusting system for space camera based on ultrasonic motor (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
作者: Sun Z.

收藏 | 浏览/下载：85/0 | 提交时间：2013/03/25

Drift angle is a transverse intersection angle of vector of image motion of the space camera. Adjusting the angle could reduce the influence on image quality. Ultrasonic motor (USM) is a new type of actuator using ultrasonic wave stimulated by piezoelectric ceramics. They have many advantages in comparison with conventional electromagnetic motors. In this paper some improvement was designed for control system of drift adjusting mechanism. Based on ultrasonic motor T-60 was designed the drift adjusting system which is composed of the drift adjusting mechanical frame the ultrasonic motor the driver of Ultrasonic Motor the photoelectric encoder and the drift adjusting controller. The TMS320F28335 DSP was adopted as the calculation and control processor photoelectric encoder was used as sensor of position closed loop system and the voltage driving circuit designed as generator of ultrasonic wave. It was built the mathematic model of drive circuit of the ultrasonic motor T-60 using matlab modules. In order to verify the validity of the drift adjusting system was introduced the source of the disturbance and made simulation analysis. It designed the control systems of motor drive for drift adjusting system with the improved PID control. The drift angle adjusting system has such advantages as the small space simple configuration high position control precision fine repeatability self locking property and low powers. It showed that the system could accomplish the mission of drift angle adjusting excellent. 2011 SPIE.

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

Stabilization and tracking precision improved based on disturbance observer (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
Sun G.; Zhu M.; Jia H.

收藏 | 浏览/下载：31/0 | 提交时间：2013/03/25

Based on the kinematics of semi-strapdown seeker the framework coordinate of the semi-strapdown seeker is established and the optical axis stabilization equation of semistrapdown seeker is deduced based on product of exponential (POE) formula. The stabilization control principle block diagram of semi-strapdown seeker is shown based on the stabilization equation. The main influence factors of the stability precision are pointed out such as friction disturbance velocity measurement noise and missile disturbance. For the sake of improving the stabilization precision and tracking precision disturbance observer was proposed in the inner loop of semi-strapdown seeker servo-control system. The low frequency external disturbance and high frequency velocity measurement noise are effectively restrained by the disturbance observer as shown in hardware-in-loop simulation and optical axis stabilization precision and tracking precision are greatly improved. 2011 IEEE.

Optical axis stabilization of semi-strapdown seeker based on disturbance observer (EI CONFERENCE) 会议论文 OAI收割
2011 International Conference on Information and Automation, ICIA 2011, June 6, 2011 - June 8, 2011, Shenzhen, China
Sun G.; Zhu M.; Yin S.; Jia H.

收藏 | 浏览/下载：21/0 | 提交时间：2013/03/25

Based on the kinematics of semi-strapdown seeker the framework coordinate of the seeker is established. The optical axis stability equation of semi-strapdown seeker is deduced by using attitude transformation matrix. Then the stability control principle block diagram of semi-strapdown seeker is shown based on the stability equation. The main factors that influence the stabilization precision are pointed out such as friction disturbance velocity-measuring noise and missile disturbance. In order to improve the stabilization precision disturbance observer was proposed in semi-strapdown seeker stability control. The low frequency external disturbance and high frequency velocity measurement noise are effectively restrained by the disturbance observer as shown in hardware-in-loop simulation and optical axis stabilization precision is improved nearly 20 times and 5 times due to two different frequencies with same amplitude. 2011 IEEE.

Pre-process technique study of a high performance remote image sensor structural Finite Element Analysis (EI CONFERENCE) 会议论文 OAI收割
2010 2nd International Conference on Computer Engineering and Technology, ICCET 2010, April 16, 2010 - April 18, 2010, Chengdu, China
作者: Zhang L.; Xu Y.-S.; Zhang L.

收藏 | 浏览/下载：27/0 | 提交时间：2013/03/25

High precision structural Finite Element Analysis (FEA) results are required in the development of a remote image sensor. HperMesh and MSC. Nastran are employed in the image sensor structural FEA. This paper discusses some technical issues about the Finite Element (FE) modeling of the image sensor. In order to obtain authentic analysis results the part-to-whole handling schema i.e. handling method and research work is implemented in a small part of the model firstly and a revised method is used in the whole structural in succession has been proposed. Some emphasis is mainly put on the FE handling of bolted joint bearing and inter-element connection. The interface handling methods such as CBEAM plus partial MPC bolted joint model hybrid element bearing model and RBE3 beam-to-solid connection have been produced and successfully implemented in the image sensor structural FEA. 2010 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.

收藏 | 浏览/下载：37/0 | 提交时间：2013/03/25

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

Study of adaptive inverse control to stale platform (EI CONFERENCE) 会议论文 OAI收割
International Conference on Computer Science and Software Engineering, CSSE 2008, December 12, 2008 - December 14, 2008, Wuhan, Hubei, China
作者: Li Y.

收藏 | 浏览/下载：24/0 | 提交时间：2013/03/25

Stable platform is a complicated nonlinear system. The common PID control can not meet the requirement of high precision and fast response. The adaptive inverse control was introduced in the system of stable platform. Based on it the system utilize its character of open circle to improve system capability. In the model building to object model and object inverse model the NARX network is used. The algorithm uses the least square method instead of least square(LMS) to identify the parameters and design the control. The simulation results show several advantages of this control strategy such as sensitive response non-overshoot good anti-disturbance and minimal stable error and showed dynamic/static performance was superior to those of conventional PID method. 2008 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：24/0 | 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.

Research on the support structure of the primary mirror of large-aperture telescope (EI CONFERENCE) 会议论文 OAI收割
3rd International Symposium on Advanced Optical Manufacturing and Testing Technologies, AOMATT 2007: Large Mirrors and Telescopes, July 8, 2007 - July 12, 2007, Chengdu, China
Yang W.; Jingxu Z.

收藏 | 浏览/下载：27/0 | 提交时间：2013/03/25

Large-aperture telescope can be used in surveying battlefield researching landform searching object real-time monitoring imaging detecting and identifying spatial targets and so on. A large-aperture telescope for achieving high resolution power is designed to monitor spatial target and image in real time. Real-time monitoring plays an important role in military conflicts. The orbit parameter of object quantity geometrical shape parameter and so on can be obtained by detect spatial target. With the development of optical technology people require larger aperture in optics-electronic (OE) system. By increasing optical aperture the ability of collecting light and resolution power in the system can be enhanced. But the support structure of the primary mirror of large-aperture telescope will be a very difficult problem. With the increase of primary mirror aperture the weight of the primary mirror will become larger than before. The root mean square (rms) of the primary mirror is affected by many factors such as deadweight deformation of heat environment and so on. Due to the primary mirror of telescope is an important component of telescope system. By reducing the weight of primary mirror precision of the system is ensured. During the designing phase one can consider the supporting project of the primary mirror synthetically and analyze it roundly according to technical requirement of optical system and the effect factors. The final structural design can be reasonable. In an astronomical telescope the surface of reflector is an important part for collecting dark radiation of celestial bodies. Its surface shape will have an effect on collecting efficiency of telescope radiant energy directly. So the rms must be very high. Optical system of large aperture small wavelength and small focus can receive maximal light intensity. For ground-based optical astronomical telescope the design proposed in the paper can satisfy the requirement of the possible minimum atmosphere seeing at astronomical observatory site and exert the use efficiency of the telescope adequately. So the accuracy of the traditional surface of reflector can assure that 90% of all the light energy can be focused on within the angle diameter range of the minimum atmosphere seeing then 100% of light energy should be focused on the angle diameter range of minimum atmosphere seeing. Because the rms of mirror is very high precise surface machining and accurate the support of mirror are very important tasks during designing and manufacturing the telescope. In the paper various support techniques of a large-aperture telescope primary mirror are discussed and a 3.5 meter telescope system at the Starfire Optical Range (SOR) overviewed simply which was operated by the Directed Energy Directorate of the Air Force Research Laboratory Kirtland AFB NM USA from the ground-based O-E system for the observations of spatial target. We also analyze Theoretical elastic deformation of the Steward Observatory 2.3 meter mirror is analyzed.