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Precision beam pointing is the key indicator for APT (acquisition, pointing and tracking) system in space laser communication. The laser travels inside the optical system and the pointing vector will be affected by an assembly error of the axis and reflectors. In this paper, the model of the optical path pointing error and coaxiality error induced by the assembly error are established; the error distribution is given and a quantitative analysis is performed. The results show that the magnitude of pointing error is affected by the axis assembling error greatly but its distribution is susceptible to the reflector assembly error. Finally, the correction of coaxiality is performed and tested. The experimental results show that the coaxiality error can be greatly improved and the mean value of the coaxiality error of a beacon path and a signal path are 14 and 9.6 μrad, respectively, which meets the requirements. This work can provide guidance for design and assembly of the APT and contribute to the improvement of its pointing performance.

At present, airborne optoelectronic pod system develops rapidly and is widely used in military and civil fields. The stable platform control system is the key part of the photoelectric pod, which is used to isolate the disturbance of the body and the external environment, maintain the stability of the LOS and ensure the clear imaging of the sensor. In general, the model of airborne electro-optical stabilization platform can not be obtained accurately, and the characteristics of the system itself are affected by the external environment. At the same time, the noise interference such as torque and sensor actuator is also uncertain. In order to solve the above-mentioned uncertainty and improve the stability accuracy of the system, this paper takes the servo system of a two axis airborne photoelectric stability platform as the research object, uses SVPWM technology to complete the hardware and software design with DSP + FPGA as the control core, uses FOG and POS as speed and position sensors. And it aims at mechanical resonance, to design a digital notch filter to restrain it. Finally, the experiment shows that when the swing amplitude is 8.5°, frequency is 0.3Hz, the stability accuracy reaches 0.005° ( $3\sigma$ ). The experiment shows that the stable platform control system has the advantages of fast response speed and high stability accuracy.

With the development of space technology and aerospace industry, space distance measurement has become an important research content in space field. The traditional radar ranging is easily interfered by space high-energy particles and electromagnetic waves in space, and the measurement accuracy is low, which cannot meet the requirements of high-precision measurement. The air in the space is thin and the temperature changes violently, so it is impossible to carry out acoustic ranging with super measurement accuracy. Laser ranging technology is an automatic non-contact measurement method, which is not sensitive to electromagnetic interference, has strong anti-interference ability and high measurement accuracy. Compared with the general optical ranging technology, it has the advantages of convenient operation, simple system and allday working. Compared with radar ranging, laser ranging has strong anti-interference ability and high precision. In this paper, a high-speed synchronous rotating mirror system is developed to meet the requirements of the splitting of the transmitting and receiving optical paths in laser ranging. It is installed in the optical path of the large-scale laser ranging system, driving the mirror body to rotate stably and at high speed, realizing the splitting of the optical path and generating the pulse signal synchronous with the mirror body position to send to the laser, which is used for the timing of launching the synchronous laser machine. Finally, through the experimental test, when the speed reaches 3000 rpm, the peak speed error is less than 1rmp（PP）, the mirror shake amount is 15.56 ", and the equipment vibration is 8.9 μ m, which meets the needs of the scheme[10].

ATP compound axis control system is an important component and key technology in the intersatellite optical communication system, which can effectively improve the tracking accuracy and system bandwidth of the photoelectric tracking system. In this paper, the principle and structure of the compound axis control system are introduced in detail, the bandwidth and error suppression ability of the system are analyzed. The simulation experiment of ATP compound axis control system is carried out by Matlab/Simulink, and the tracking precision of the system is less than 2µrad. The experimental results show that the ATP compound axis control system has the advantages of good dynamic performance, high tracking accuracy and strong error suppression ability.

When the four-quadrant detector is detected using the pyramidal prism to reflect the light, the dihedral angle error causes the spot offset. In this paper, the relationship between the reflection spot offset and the three dihedral angle errors is analyzed by combining the pyramid model with the detector detection principle, and the influence of the dihedral angle error on the center shift of the reflected light spot is explored qualitatively and quantitatively. The simulation results show a high degree of central symmetry, which can be used to eliminate the system error resulting from the dihedral angle error of the corner prism, in order to minimize detection accuracy to 0.1μm. In addition, The simulation results provide a theoretical basis for the subsequent coaxial accuracy test.

The star sensor is a high-precision attitude sensitive measuring instruments, which determine spacecraft attitude by detecting different positions on the celestial sphere. Imaging camera is an important portion of star sensor. The purpose of this study is to design a driving circuit based on Kodak CCD sensor. The design of driving circuit based on Kodak KAI-04022 is discussed, and the timing of this CCD sensor is analyzed. By the driving circuit testing laboratory and imaging experiments, it is found that the driving circuits can meet the requirements of Kodak CCD sensor.

Photoelectric rotary table as the main test tracking measurement platform, widely use in shooting range and aerospace fields. In the range of photoelectric tracking measurement system, in order to m eet the photoelectric testing instruments and equipment of laboratory and field application demand, research and design the portable photoelectric rotary table data acquisition and analysis system, and introduces the FP GA device based on Xilinx company Virtex-4 series and its peripheral module of the system hardware design, and the software design of host computer in VC++ 6.0 programming platform and MFC package based on class libraries. The data acquisition and analysis system for data acquisition, display and storage, commission control, analysis, laboratory wave playback, transmission and fault diagnosis, and other functions into an organic whole, has the advantages of small volume, can be embedded, high speed, portable, simple operation, etc. By photoelectric tracking turntable as experimental object, carries on the system software and hardware alignment, the experimental results show that the system can realize the data acquisition, analysis and processing of photoelectric tracking e quipment and control of turntable debugging good, and measurement results are accurate, reliable and good maintainability and extensibility. The research design for advancing the photoelectric tracking measurement equipment debugging for diagnosis and condition monitoring and fault analysis as well as the standardization and normalization of the interface and improve the maintainability of equipment is of great significance, and has certain innovative and practical value. Keywords : portable, data-acquisition and analysis, FPGA, VC++, fault diagnosis

Photoelectric rotary table is mainly used in the defense industry and military fields, especially in the shooting range, target tracking, target acquisition, aerospace aspects play an important one. For range photoelectric measuring equipment field test application requirements, combined with a portable photoelectric rotary table data acquisition hardware system, software programming platform is presented based on the VC++, using MFC prepared PC interface, the realization of photoelectric turntable data acquisition, analysis and processing and debugging control. The host computer software design of serial communication and protocol, real-time data acquisition and display, real-time data curve drawing, analog acquisition, debugging guide, error analysis program, and gives the specific design method. Finally, through the photoelectric rotary table data acquisition hardware system alignment, the experimental results show that host computer software can better accomplish with lower machine data transmission, data acquisition, control and analysis, and to achieve the desired effect, the entire software system running performance is stable, flexible, strong practicality and reliability, the advantages of good scalability.

This paper proposes an approach to design a simulation method based on Adams and Simulink to improve performance of the stable platform. First, this paper gives an Adams/Simulink co-simulation method of airborne stable platform. Second, it designs mechanic model in Adams and control model in Simulink. Finally, simulate mechanic and control model of airborne stable platform, the simulation result shows that the co-simulation of Adams and Simulink is feasible. In the Adams model, it designs different error factors as follows: friction disturbance, motor disturbance, aircraft vibration disturbance and gear backlash. The simulation result is further close to the actual situation. Therefore, the co-simulation method of this paper is better than traditional simulink method. The design of co-simulation has guiding significance for improving the mechanic and control module of airborne stable platform.

In the research of electro-optical pod, this paper propose a mission requirements that continuous zoom lens system is using for measuring angle in the process. This paper analyzes the influence of angle measurement accuracy from focal length and optical axis errors in the process of continuous zoom, and given the mathematical model of the influence of angle measurement accuracy. The simulation analysis indicated that Angle measuring accuracy is affected by the process of continuous zoom. The simulation analysis results have certain instructive significance to engineering practice.

The virtual instrument is the main content of instrument technology nowadays. This article details the implementation process of the virtual oscilloscope. It is designed by LabVIEW graphical programming language. The virtual oscilloscope can achieve waveform display, channel selection, data collection, data reading, writing and storage, spectrum analysis, printing and waveform parameters measurement. It also has a friendly user interface and can be operated conveniently.

Based on the three joint of robotic arm, to track an arbitrary continued path, a moving control algorithm based on Particle Swarm Optimization was studied in the visual servo system of three-joint robot arm in the paper. The optimization is based on the minimum error of distance between the end point of robot arm and the position of input path. In this case, the adaptability and intelligent of the robot would be improved with complicated working environment and task. The simulation experiment shows that the performance of system to track a continuous trajectory is Optimized, and has strong robustness.

This paper introduces the up-to-date research in on-demand routing for ad hoc mobile networks. The on-demand routing protocols arc divided into three categories: flat flooding routing, flat limited routing and hierarchy routing. In flat flooding routing protocols, DSR, ABR, AODV and ZRP arc discussed. In flat limited routing protocols LAR and RDMAR arc discussed. In hierarchy routing protocol CBRP is introduced. For each routing protocol, this paper not only introduces the contents of the routing protocol, but also the merits and drawbacks, and evaluates these protocols based on a given set of parameters such as communication complexity, time complexity, route metric, the range of route discovery, the periodically packets and route maintenance. This paper also evaluates some drawbacks of above routing protocols, for example initial route delay, supporting of unidirectional links and flooding broadcast, and proposes some optimized schema for these drawbacks. These schemas arc cluster based hybrid routing schema to mitigate the flooding broadcast and initial route delay, and unidirectional ad hoc on-demand routing schema to support the ad hoc mobile networks with unidirectional links. Furthermore this paper proposes an optimization schema based on rough set for limited routing protocols, which is that the intermediate nodes update the zone of route discovery by their newer location and/or distance information. Finally authors suggest the research direction in routing for ad hoc mobile wireless networks in the future.