This PDF file contains the front matter associated with SPIE Proceedings Volume 7129, including the Title Page, Copyright information, Table of Contents, and the Conference Committee listing.

In order to get good accuracy, designer used to consider how to place cameras. Usually, cameras placement design is a multidimensional optimal problem, so people used genetic algorithms to solve it. But genetic algorithms could result in premature or convergent problem. Sometime we get local minimum and observe vibrating phenomenon. Those will get inaccurate design. So we try to solve the problem using the changing environment genetic algorithms. The work proposes giving those species groups difference environment during difference stage to improve the property. Computer simulation result shows the acceleration in convergent speed and ability of selecting good individual. This work would be used in other application.

A phoropter is one of the most popular ophthalmic instruments used in current optometry practice. The quality and verification of the instrument are of the utmost importance. In 1997, International Organization for Standardization published the first ISO standard for requirements of phoropters. However, in China, few standard and test method are suggested for phoropters. Research work on test method for phoropters was carried out early in 2004 by China National Institute of Metrology. In this paper, first, structure of phoropters is described. Then, theoretical considerations for its optical design are analyzed. Next, a newly developed instrument is introduced and measurements are taken. By calibration, the indication error of the instrument is not over 0.05m^-1. Finally, measurement results show that the quality situation of phoropters is not as good as expected because of production and assembly error. Optical design shall be improved especially for combinations of both spherical and cylindrical lenses with higher power. Besides, optical requirements specified in ISO standard are found to be a little strict and hard to meet. A proposal for revision of this international standard is drafted and discussed on ISO meeting of 2007 held in Tokyo.

A distributed RC transmission-line approximation is used to analyze the transient response characteristic of one-dimensional (1D) position sensitive detectors (PSDs). A generalized mathematical model has been developed for a moving light source illuminated on the PSD. The relative error curve has been given between the computed and true incident positions of light under different moving speeds, and the impact of different starting positions has been analyzed on the position detection error of light. It is shown that when the moving speed is less than the tenth characteristic speed, the output photocurrents can be rather linearly detected as long as the measuring time is longer than the delayed time maximum. It is also found that the distance between the original point and starting position should be as short as possible in order to obtain the correct incident position of light. The computed photocurrents have been compared with data simulated using the ANSYS software, and qualitative agreement is found.

Integral photography (IP) technology provides a method for recording and display of 3-dimensional scenes. In this paper, we analyzed the relation between the resolution of an image capturing and the optical parameters of the system. The final resolution of the image that the observer actually views is derived; the resolution limitation and the viewing area of the integral photography are discussed. Theoretical analyses of the technology have shown that the integral photography (IP) can produce image at great distance with the same resolution as conventional 2-D displays.

The imperfect fiber in fiber optic gyro (FOG) can not keep the polarization of light under the effect of external magnetic field, and the output of FOG varies. Based on analyzing the output of FOG collected at different placed modes but with the same external magnetic field and the same magnetic shielding proposes the scientific way of how to place FOG when we are testing the magnetic shielding effectiveness. This is also useful to guide the utilization of ANSYS in simulating the design and analyzing the magnetic characteristic of the magnetic shielding instrument (MSI) for FOG.

A two-phase flow in a translucent cylinder pipeline was studied using high-speed video system. Series of images were taken for recording flowing information. An innovative bubble filling algorithm named infective algorithm was used to fill the center of edge closed bubble in the binary image. The modified infective algorithm was applied to the binary images with ringent bubbles in this paper, which make up for the disadvantage of the simple infective algorithm. The area and the geometric center of the bubble were acquired from the filled image. Then the track of bubble rising was acquired by the geometric center. Experimental results have shown that the bubble could be well tracked.

Computer vision method is an important technology for non-contact and non-destructive measurement. A lot of research is focusing on the 3D vision technique. Shape from stereo is the most popular method because it can provide high accuracy and high exactness measurement result. But if the surface is complex, the measurement result is always poor. So how to make sure the 100% stereo matching rate is an important task for the development of shape from stereo method. A novel strip matching method, which can ensure 100% matching accuracy, is proposed in this paper. It doesn't need any other assistant symbol or flag. The proposed dichotomy strip matching method is proved to a technique which high precision, low costs, easy operation, and an automatically matching method. Furthermore, it can be widely used in most of 3D vision recovery systems.

Three-dimensional finite element model was developed to simulate the X-ray lithography mask distortion during electron-beam writing (EBW). Equivalent heat flux density method was proposed and the transient thermal stress simulation was done. The results show that the in-plane distortion (IPD) of the mask fluctuates with the time. The maximum value is 8.24 nm, and the direction is deviated from the electron beam center. The maximum out-of-plane distortion (OPD) is 9.75μm. The direction is normal to the pattern window, and occurred in the center of the beam center.

This paper introduces a precise way of using linear structured light sensor and CCD camera to measure the workpieces' shoulder characteristic size. The high precision measuring system and the core algorithms are mentioned in the paper to test the deformation of the light plane when the light meets the workpieces' shoulder surfaces. The measuring principle and the set-up of the system are described in detail. The core sub-pixel algorithms are proposed to locate the deformation of the structured light in order to improve the final precision. The experiments demonstrate the high repeatability and accuracy of the system. The experiments of accuracy estimation show the measuring precision could reach 0.05 mm.

In this paper, an adaptive image enhancement method based on neural networks is proposed. The low frequency components of the image can be obtained by average filter and the high frequency components of the image are obtained by subtracting the low frequency from the original image. The enhanced image is obtained by adding the original image to the high frequency components multiplied by the scale factor. The masking size of the average filter and the scale factor are given by the constructed neural net in terms of the mean and standard deviation of the image. Real experiments has been to test the proposed method and very good result has been obtained.

Camera calibration is the basic of machine vision, the accuracy of feature point detection and the automation of camera calibration process is very important in actual high precision measurement. The planar pattern with circle feature has its own advantage compared with chessboard calibration pattern; it is easy to manufacture, and insensitive to threshold. Although there is a position distortion in detecting the projected centre of circle for perspective projection, the feature point which is the image of the center of the circle can be computed accurately based on the geometric and algebraic constrains of projected concentric circles. After the feature points is detected, the set of feature points on the calibration pattern and the points in the camera images must be matched, manual or user assisted methods are often used to solve the matching problem. This paper also describes a simple technique based on Delaunay triangulation to automatically match the feature points recovered by concentric circles. The experiments show that the method is excellent in actual camera calibration using concentric circles array.

In the real-time inspection technology of the printed circuit board (PCB), the matching comparison method is widely used with its simple and easy algorithm to implement. However it has kinds of flaws such as high rate of false report and mutually disturbs among different patterns in comparing process. Therefore this research improved the conventional matching comparison method, proposed the multilayer matching comparison method that based on the multi-threshold values partition image, enhanced the PCB inspection accuracy and reduced the phenomenon of false report. This technique is especially suitable for the inspection of PCB image that has complex gray-levels and multimodal histogram, and can also preliminarily classify the defects according to the partition layers processing.

The 3-D foot-shape measurement system based on laser-line-scanning principle was designed and 3-D foot-shape measurements without blind areas and the automatic extraction of foot-parameters were achieved. The paper is focused on the study of the system structure and principle and image processing techniques. The key techniques related to the image processing for 3-D foot shape measurement system include laser stripe extraction, laser stripe coordinate transformation from CCD cameras image coordinates system to laser plane coordinates system, laser stripe assembly of eight CCD cameras and eliminating of image noise and disturbance. 3-D foot shape measurement makes it possible to realize custom-made shoe-making and shows great prosperity in shoe design, foot orthopaedic treatment, shoe size standardization and establishment of a feet database for consumers.

This paper introduces a fast-moving target tracking system based on CMOS (Complementary Metal-Oxygen Semiconductor) image sensor. A pipeline parallel architecture of region segmentation and first order moment algorithms on FPGA (Field Programmable Gate Array) platform enables driving the high frame rate CMOS image sensor and processing real-time images at the same time, extracting coordinates of the bright target spots in the high-rate consecutive image frames. In the end of this paper, an experiment proved that this system performs well in tracking fast-moving target in satisfying demand of speed and accuracy.

A high accuracy line-of-sight (LOS) Stabilization system based on digital control technology was designed. The current feedback closed-loop system was introduced which uses the CCD graphic and resolver to constitute the position closed-loop and uses the optic fiber gyro to constitute the rate closed-loop. In order to realize zero steady-state error of angular output in counteracting disturbance from carrier, a PII² (proportional-integral-double integral) control scheme is proposed. The hardware configuration and software system is presented. Experimental results show that the system has perfect dynamic and static performance and the technical requirements were satisfied.

On a container dock, the container truck must be parked right under the trolley of the container crane before loading (unloading) a container to (from) it. But it often uses nearly one minute to park the truck at the right position because of the difficulty of aiming the truck at the trolley. A monocular machine vision system is designed to locate the locomotive container truck, give the information about how long the truck need to go ahead or go back, and thereby help the driver park the truck fleetly and correctly. With this system time is saved and the efficiency of loading and unloading is increased. The mathematical model of this system is presented in detail. Then the calibration method is described. At last the experiment result testifies the validity and precision of this locating system. The prominent characteristic of this system is simple, easy to be implemented, low cost, and effective. Furthermore, this research work verifies that a monocular vision system can detect 3D size on condition that the length and width of a container are known, which greatly extends the function and application of a monocular vision system.

A new installation structure of optical fiber Fabry-Perot (F-P) cavity is proposed to function in an optical microphone. The F-P cavity consists of an optical fiber end with self-focused lens and a sound-sensitive membrane. Distance between the two parts is the F-P cavity length. The sound membrane is produced by semiconductor sculpture, which guarantees its tiny size, uniform thickness and high sensitivity to sound. The membrane responds to the sound vibration and vibrates in concavo-convex shape, which results in the change of cavity length, so the F-P cavity performs as an optical microphone. A mathematical model for this kind of arc F-P cavity is also proposed to study the optical microphone. The arc end is assimilated to a step-like model, so the arc F-P cavity equals an assembly of annular plane-end F-P cavities. The mathematical model is educed by simple integral of the annular plane-end F-P cavities and multi-beam interference theory. Relevant simulation and experiments are executed, which confirm the accuracy of the mathematical model and feasibility of the installation structure.

The optical design of projection objectives is a key to the LCD projection technology, which will have a great impact on the quality of projection image. The method of the design for the LCD projection objective is very close to that for photographic lens. In this paper, a LCD projection objective is designed. Based on the inverse telephoto objective, the initial optical structure is obtained through complication so that the seven primary aberrations of the initial system can be corrected. The optical design software ZEMAX is employed to have the initial system optimized. The optimization result meets the technique requirements: the effective focal length 50mm, F/6, the full field of view ±20°, distortion greater than 0.1% and MTF above 0.1 at 40lp/mm.

Large-scale stereo vision sensor is of great importance in the measurement for large free-form surface. The intrinsic parameters of cameras and the structure parameters of the stereo vision sensor should be calibrated beforehand. Traditional methods are mainly based on planar and 3D targets which are expensive and difficult to manufacture, especially for large dimension ones. A calibration method for stereo vision sensor based on one-dimensional targets is proposed. First random place two 1D targets, and acquire multiple images of the targets from different angles of view with camera. Solve the intrinsic parameters of camera with the constraint that the spatial angle of the two ID target are constant. Then set up the stereo vision sensor with two calibrated cameras, and acquire multiple images of a 1D target of unknown motion. Based on the constraint of the known distance between two feature points on the target, estimate the initial value of the structure parameters with linear method and the precise structure parameters of stereo vision sensor with non-linear optimization method by setting up the minimizing function involving the scale factors. Experimental results show that, the measurement precision of the stereo vision sensor is 0.052mm, with the working distance of 3500mm and the measurement scale of 4000mm × 3000mm. The method proposed is proved to be suitable for field calibration of stereo vision sensor in application of large-scale measurement for its easy operation and high efficiency.

This anomalies detection approach seeks the directions that maximize the projection index, so as to gain the anomalies structure information. Using genetic algorithm in this approach can search accurate optimal projection directions, but it's a computation-intensive task. So, a parallel algorithm under distributed memory system was presented. The projection directions were searched efficiently by parallel genetic algorithm model, and the projection directions' precision was guaranteed by using a strengthened terminal qualification. Then, the detected anomaly components were wiped off by projecting the data onto the subspace orthogonal to the previous projection directions, and the other anomalies were searched in the residual space. The final task of projection and objects segmentation was also completed in parallel. Using an OMIS hyperspectral data to test the parallel algorithm's performance under an eight-node cluster, the process time reduced from 15 minutes to 2.8 minutes. The results show the validity and comparative good parallel efficiency.

There are different kinds of noise in the optical gyro output signals. The signals imbedded noise are always non-stationary. Recent works have demonstrated that the noise can be separated from the original signal by the empirical mode decomposition (EMD). However, there are some shortages in the original algorithm of EMD, for example, the envelope mean computation and the time-consuming fitting. An improved EMD is introduced where quasi-mean filter and the extension segment approximation are proposed. The new EMD is used in ring laser gyro signal analysis and de-noising, and the Allan variance is used to evaluate the result.

In order to fabricate large aperture optical aspheric mirrors/lenses with nanometer shape accuracy, computer-controlled grinding and polishing processes are necessary. However, large work-piece usually has a relative high weight and size, which is inconveniently to perform interferometric testing during fabrication. A novel machining tool with five-axis and work-piece table vertical overturning setup is proposed, which is designed with the functions of both grinding and polishing, and characterized as on-machine testing mechanism. Analysis aims on the structure and stability indicates the designed machine with reasonable parameters and with the potential of making high quality optical mirrors or lenses.

The image coding algorithm based on quadtree partitioning, which is presented by Yuval Fisher, has become the mainstream of fractal image compression. However, in the conventional Yuval Fisher's theory, the threshold of distance between range blocks and domain blocks is pre-fixed mainly by experience, which does not take the practical statistical characteristics of range blocks into account for automatic valuation. Thus the coding algorithm could not adapt to various input images well, and sometimes the performances on certain images are not further optimized. To overcome this shortcoming, an improved adaptive threshold (AT) for quadtree partition is presented in this paper. Compared with the fixed threshold (FT) partition, this improved method could shorten coding time and obtain higher PSNR that have been demonstrated by the experimental results. Furthermore, the decoded images get more subjective acceptances in accordance with the standard of Human Visual System (HVS).

This paper discusses the characteristic of two-fiber, intensity modulated FODS, a type of high sensitivity displacement sensor, from a theoretical prospective, focusing on the geometrical parameters including fiber aperture (NA), radius of fiber core (r), lateral separation of the transmitting and receiving fibers (s), the angle between the two fibers (2a), and the reflector curvature radius (R_c). A mathematical model is set up to investigate the influence on the performance of FODS introduced by the variation of these parameters, and the simulation results are also presented to conduct farther study in this field.

We present a method for automatically registering multi-view range images. For each range image in the data set, corresponding point sets of its feature points are established, on the rest of the scans, by matching regional point descriptors. Then we build a statistic model to estimate the likelihood of the image overlapping with each of the rest ones to select candidate overlapping range images. Candidate overlapping pairs of range images are verified and registered by enforcing geometric constraints on point matches and ICP algorithm. Finally the absolute positions of all range images are established and fine-tuned. Experiment result demonstrates efficiency of the method in picking up potential overlapping images, and establishing initial transformation between overlapping pairs. The proposed method offers a good solution to automatically building complete 3D model of objects from unordered 3D scan data sets.

Reflective optical systems are used widely in space optics and polarization sensitivity is one of the important factors to describe the polarization properties of the light passing through optical systems. In this paper, a unified discussion of the polarization sensitivity theory is presented and the method of using polarization ray tracing is used to analyze the polarization sensitivity caused by the reflectors in reflective optical systems. The Mueller calculus used in polarization ray tracing is studied to calculate the linear polarization sensitivity LPS in reflective optical systems. The changed rules of the polarization sensitivity are also studied. A Ritchey-Chretien system is presented as an example system to be analyzed. According to the results of the polarization analysis, it is proved that the change of the polarization sensitivity is serious in the reflective optical systems those have high numerical aperture, large incident angles or work in wide wavelength.

This paper makes improvements on the algorithm of identifying blur support size proposed by Li Chen in blind image restoration to accommodate to the moderate/intense noise circumstance. The prior method mainly constructs a whiten filter referring to the image characteristics based on ARMA (Autoregressive Moving Average) model, and calculates the correlation of whiten filtered image with different shifts, thus gets the estimated blur size equal to the shifts at the minimum of correlation. However, this method is difficult to accurately identify blur size even with moderate additive noise. Some procedures are taken before calculating the correlation to ameliorate the estimation accuracy, including regarding edge neighborhoods as valid regions for calculating correlation in the whiten filtered image and implementing filtering to further reduce noise interference. Experimental results represent that the correlation attains its minimum when the shift distance meets certain relationship with actual blur size, thus show the improvements are valid for the case of moderate/intense contamination.

The paper presents a practical system based on DSP and USB2.0 to realize the transmission of digital infrared sequence images. The hardware design of system is analyzed in detail, in which USB interface controller is described, moreover the development of DSP software and the application program on host PC is also introduced. The system interfaces PC with EZ-USB chip CY7C68001. It is based on bulk transmission with one frame image as a unit, and the chip is configured in Slave FIFO, asynchronous read/write operating mode. Experimental results show that the developed system can work properly and achieves the data transfer speed of 50 Mbps, thus it can meet the requirement for real time transfer of infrared sequence image sized 256×256×8 bits per frame at 100 frames per second.

In this pper, a new approach to wheel mobile robot navigation with global vision system is proposed. The moving object detection method with GMM (Gaussian Mixture Model) based background modeling is applied to extract the moving object from the image captured by a wide angle camera fixed on ceiling. Through a mapping transformation, the position of robot in the real world can be measured and the Extended Klman Filter is employed to obtain more accurate navigation data. With a series of simulations and experiments, the validity of this approach to wheel mobile robot navigation is verified.

Digital holography is an emergent imaging technique which provides complete three-dimensional information of an object. An off-axis Fresnel digital holographic system with pre-magnification is built. Experimental investigations have been performed for a USAF test target. By using four autofocusing algorithms the optimal recording distance of the recorded hologram is determined accurately. The experimental results show that the variance algorithm is the most effective one for digital holographic microscopy. Based on the obtained recording distance, the phase image of the investigated microscopic object is reconstructed accurately by associated applying the automatic phase aberration compensation procedure proposed by T.Colomb with the manual adjustment method. The lateral resolution with better than 2.38 μm and the axial resolution of 10nm has been achieved experimentally.

A wavelength demodulation detection scheme was proposed based on the polarization mode interference in polarization maintaining optical fiber (PMF), and the sensing equation was obtained. Compared to the conventional intensity-based detection technique, this wavelength demodulation technique overcomes the effect of the source power fluctuation and the variation of optical loss that occurs in the transmission fiber. An experiment system was setup and the relationship between the frequency of wavelength domain and temperature was obtained within the temperature range -40 °C to 80 ° C. Experimental results agree well with theoretical prediction.

In general practical applications, the point spread function (PSF) of the imaging system, the imaging process, and the observation noise, are unknown a priori information. Therefore, the identification of the PSF is a challenging and difficult problem in the world. The algorithm of identification of the PSF and the restoration of the blurred images based on the priori blur models (known as the PBM algorithm) is proposed. In practical application, the priori models of the PSF mainly consist of the linear motion blur, out of focus blur and the Gaussian blur. In the situation of that the degradation process is formed by the one of the above point spread functions, the PSF can be formulated in parametric model. The corresponding parameters of the model are determined by the algorithm proposed in this paper. Thus, the PSF is obtained according to the parameter of the model consequently. First, the parameter changing scope and the increment step length of the parameters are provided based on the original guess. Second, the criterion that the Euclid length of the difference between the observed image and blurred image corresponding to the PSF is minimized is incorporated in order to determine the parameter of the PSF. Therefore, the PSF is identified by the parametric model and the original image is estimated via the ordinary image restoration algorithms. In this paper, we applied the Wiener filter to restore the original images. The experimental results show that the identified result of the PSF is reliable and accurate and the restoration effect with the identified PSF is better when the observed image have high signal to noise ratio (SNR).

The Bessel light triangulation system has the advantages of long measurement range, high accuracy and resolution over the traditional laser triangulation system. Unfortunately the measurement accuracy is degraded due to various noises in practical application. In order to improve the measurement accuracy, a novel effective location method for the center spot of the Bessel light is presented in this paper through the improved spin filtering and gray scale bilinear interpolation. In this method, the stripe orientation is accurately estimated by using surface fitting for gray scale, determine the gray scale contoured window based on a map of the stripe orientation, and apply grey relational analysis so as to remove the interference noises. Then the center spot region, roughly obtained by adaptive threshold method, is implemented bilinear interpolation for gray scale to specify the accurate location of the center spot, which is extracted with the centroid method for gray scale. Through the sample and simulation analysis, the proposed method is insensitive to the imperfection of the Bessel light intensity distribution and has better performance of anti-noise. In addition, the result of locating the center spot is more reliable with the accuracy of sub-pixels.

Uses of digital correlation analysis of speckle intensities are described in measurements and monitoring of rough surfaces. First, theoretical relationships for correlation properties of speckle patterns are surveyed in terms of the intensity cross-correlation between two patterns. They consist of speckle displacement and decorrelation, each of which is related to the position and the reduction of correlation peak, respectively. For examples, speckle displacement is applied to measurement of strain by a laser-speckle strain gauge and a speckle extensometer both of which are perfectly non-contacting. Speckle decorrelation is used for the measurements of surface roughness and monitoring of paint drying process. Relationships with digital holography that enables to derive 3-d speckle cross-correlation are also mentioned.

In order to improve the performance of heat protection for induction motor, a novel method for temperature monitoring of stator winding is presented. The occurring instants of the signal change can be localized by wavelet transform in time-frequency domains. The accuracy of the estimated stator and rotor temperature is mainly determined by the accuracy of the employed model and the involved machine parameters. By means of motor mathematical model, the stator resistance is identified and the wavelet network is utilized for motor speed estimation. The wavelet network determines the mapping relationship between the stator voltage, stator current, power factor angle and the rotor speed. For completing the network parameter initialization, the improved least squares algorithm is used in training procedure. According to the principle that the metal resistance depends on its temperature, the stator temperature can be calculated on-line. The simulation and experiment results show that the proposed technology improves heat stability for asynchronous motors.

The inverse kinematics control of a robotic manipulator requires solving non-linear equations having transcendental functions and involving time-consuming calculations. Particle Swarm Optimization (PSO), which is based on the behaviour of insect swarms and exploits the solution space by taking into account the experience of the single particle as well as that of the entire swarm, is similar to the genetic algorithm (GA) in that it performs a structured randomized search of an unknown parameter space by manipulating a population of parameter estimates to converge on a suitable solution. In this paper, PSO is firstly proposed to optimize feed-forward neural network for manipulator inverse kinematics. Compared with the results of the fast back propagation learning algorithm (FBP), conventional GA genetic algorithm based elitist reservation (EGA), improved GA (IGA) and immune evolutionary computation (IEC), the simulation results verify the particle swarm optimization neural network (PSONN) is effective for manipulator inverse kinematics control.

An effective scheme of parameter identification based on wavelet neural network is presented for improving dynamic performance of direct torque control system. The wavelet transform is localized in time-frequency domains, yielding wavelet coefficients at different scales. This gives the wavelet transform much greater compact support for analysis of signals with localized transient components. The input nodes of wavelet neural network are current error and change in the current error and the output node is the stator resistance error. To fulfill the network structure parameter, the improved least squares algorithm is used for initialization. The stator flux vector and electromagnetic torque are acquired accurately by the parameter estimator once the instants are detected. This function can make induction motor operate well in low region and can optimize the inverter control strategy. The simulation results show that the proposed method can efficiently reduce the torque ripple and current ripple.

By combining wavelet analysis and neural network, a new approach for condition monitoring is presented for rotating machine fault. The wavelet analysis can accurately localize the features of transient signal in time-frequency domains. The wavelet transform technology is appropriate for processing of fault signals consisting of short-lived, high-frequency components closely located in time as well as long duration components closely spaced in frequency. In a view of the inter relationship of wavelet decomposition theory, the crucial components as features are inputted into radial basis function for fault pattern recognition. In order to acquire the network parameters, the improved Levenberg-Marquardt optimization technique is used for training process. By choosing enough samples to train wavelet network, the fault pattern can be determined according to the output results. Also, the robustness of wavelet network for fault diagnosis is discussed. The applied results show that the proposed method can improve the performance for real-time monitoring of vibration fault.

A new method for stator resistance identification based on wavelet network is presented to improve the operating performance of induction motor. The ripple of the torque is kept constant, resulting in a variable switching frequency, which depends on the tolerance band of the control. Due to wavelet transform behaving good localization property in both time and frequency space and multi-scale property, the wavelet function is adopted as the basic function of neural network. The current error and the change in the current error are the inputs of the wavelet network and the stator resistance error is the output of the wavelet network. The network parameters are initialized by the improved least squares algorithm. The parameters of wavelet network are tuned online to approximate the unknown nonlinear model with an appropriately chosen adaptive mechanism. The proposed method is proved to be efficient to reduce the torque ripple and current ripple by detailed comparison simulation results.

Edger rolling mill is a load system in which the upper and the lower cylinder actuate a side vertical roller at the same time. Due to the linkage of the load, the output and control of two channels influence each other. Synchronic-control issue is discussed aim to the system with serious coupling. Neural network inverse as decoupling controller is proposed to account for the complicated process dynamics characterized by nonlinear, time-varying, uncertain and load couple properties. Firstly, the reversibility of the system is analyzed and the ANN inverse dynamic is constructed based on a feed forward and neural network structure with enlarged back propagation algorithm. Secondly, the system is changed into two pseudo-linear sub-system through connecting the controlled system and inverse dynamic model in series. Aim to two pseudo-linear sub-system pole assignments method is proposed to enhance the whole system performance. A series simulation was conducted and results showed the proposed controller does better than traditional PID not only on decoupling but also on the transient response, as well as robustness under vary conditions.

In networked control systems (NCS) communication networks affect the performance of system and even cause instability. This paper explains the basic problems of networked control systems, expatiates the general methods of system modeling and stability Analysis, summarizes the current system control methods and introduces the common system simulation tools. Finally points out the problems to be dealt with in NCS and the future development directions.

In the ground test station of AC motor driven airborne hydraulic pump (referred to as AHP, hereinafter), speed adjusting is usually worsened by the high order, nonlinearity and time-varying features of AC motor, as well as the nonlinearity of the hydraulic system. In order to solve these problems a new complex control method based on Fuzzy-PID control theory is brought forward. The control method adopts fuzzy controller to enhance the system's tracing features under big error conditions and adopts parameter self-modifying Fuzzy-PID control to eliminate static errors under small error conditions. Simulation results show that the complex controller has faster response, higher accuracy, stronger robust, compared with the general PID controller. The AHP speed and robust requirements can be satisfied.

The control model of RLG digital frequency stabilization system, composed of a proportional element, an inertial element, a nonlinear element and a digital controller, was established. The model parameters were acquired by frequency sweeping and searching firstly. Then, the principle of frequency stabilization control was presented. The nonlinear element was linearized by introducing a square wave and Ziegler-Nichols method was used to design a PI controller for the linearized system whose feasibility was proved by SIMULINK and experiment results. Finally, experiment results showed that RLG output instability is less than 0.05%, which satisfies the requirement of application.

One kind of new programmable controller(PLC) is introduced in this paper. The advanced embedded microprocessor and Field-Programmable Gate Array (FPGA) device are applied in the PLC system. The PLC system structure was presented in this paper. It includes 32 bits Advanced RISC Machines (ARM) embedded microprocessor as control core, FPGA as control arithmetic coprocessor and CAN bus as data communication criteria protocol connected the host controller and its various extension modules. It is detailed given that the circuits and working principle, IiO interface circuit between ARM and FPGA and interface circuit between ARM and FPGA coprocessor. Furthermore the interface circuit diagrams between various modules are written. In addition, it is introduced that ladder chart program how to control the transfer info of control arithmetic part in FPGA coprocessor. The PLC, through nearly two months of operation to meet the design of the basic requirements.

This paper proposed three control schemes using model reference adaptive control (MRAC) and RBF neural network(RBFNN). Through comparision, it proposed a MRAC scheme with RBFNN compensator for speed control of high precision servo systems. The MRAC scheme is used to give better solutions with online adaptation and guarantee the stablity of the system. In the feedback channel, the parameter K_p makes it easier to design the system poles. By using a PI controller before K_p, the dynamic performance of the system is improved. As a speed compensate controller, the RBFNN is designed parallel with the model reference control. The RBFNN controller is able to online learn the unknown model dynamics, parameter variation and disturbance of the system. Thus, it is feasible to preserve favorable model-following characteristics under various conditions. The effectiveness of the proposed control scheme is demonstrated by simulation. It is found that the proposed scheme can reduce the plant's sensitivity to parameter variation and disturbance. High precision performance is obtained when given constant and sine wave disturbance at the same time.

Based on visualization test of biotrickling bed, we analyze the dynamicmodel of the purification process, and get the dynamic model on liquid flux and purification efficiency. The adaptive control strategy is applied in the purification process. The simulation test proves that under the same disturbance the adaptive control strategy is more effective than PID.

In this paper, a new model reference adaptive control (MRAC) scheme based on neural network (NN) for servo system position tracking control is proposed. This scheme consists of an MRAC controller and an online NN controller in velocity-loop. The velocity-loop is encircled with a position-loop which used a traditional PID controller. For reducing influence which arose from modeling error, unknown model dynamics, parameter variation and load changes on the velocity-loop, the NN controller is introduced to counteract the various influence mentioned above dynamically, adjust system to track the approximate velocity-loop reference model. The negative gradient method is used in MRAC and NN controller parameters update. In this way, the position-loop is not sensitive to the disturbance on velocity-loop, and the whole velocity-loop can be treated as a simple linear model when designing the other parts of the system. The simulation results show that the proposed method can counteract the disturbance effectively.

As a kind of radioactive gas, radon has the characteristics of radioactive decay and statistical fluctuation. The radon concentration is always in a dynamic changing process, it is difficult to implement the accurate control. In order to make the radon chamber keep a stability radon concentration, a fuzzy radon replenishment control model based on Takagi-Sugeno model is proposed. According to the idea of Takagi-Sugeno model, a two-dimensional fuzzy controller include two inputs and single output is designed. The input variables of this fuzzy controller is E and EC, E is the deviation between the actual concentration and expected radon concentration, EC is the change rate of radon concentration. the output variable of controller is U that used to control the valve of radon source. The fuzzy control rule of radon concentration is build by reasoning machine. The accurate control output variable is obtained by anti-fuzzy method and be used to control the valve state radon source. A radon chamber control system is developed by Labview based on the fuzzy control model. The experimental results show that the fuzzy control method improve the robustness of dynamic radon replenishment.

Quadruped robot has attribute of serial and parallel manipulator with multi-loop mechanism, with more DOF of each leg and intermittent contact with ground during walking, the trot gait of quadruped robot belongs to dynamic waking, compared to the crawl gait, the walking speed is higher, but the robot becomes unstable, it is difficult to keep dynamically stable walking. In this paper, we mainly analyze the condition for the quadruped robot to realize dynamically stable walking, establish centroid orbit equation based on ZMP (Zero Moment Point) stability theory, on the other hand , we study contact impact and friction influence on stability and energy efficiency. Because of the periodic contact between foots and ground, the contact impact and friction are considered to establish spring-damp nonlinear dynamics model. Robot need to be controlled to meet ZMP stability condition and contact constraint condition. Based on the virtual prototyping model, we study control algorithm considering contact condition, the contact compensator and friction compensator are adopted. The contact force and the influence of different contact conditions on the energy efficiency during whole gait cycle are obtained.

Alignment of carrier-based aircraft inertial navigation system (slave inertial navigation system, SINS for short) on moving carrier needs velocity and attitude information from carrier inertial navigation system (MINS). If velocity and angular rate of the carrier are compensated, SINS alignment will be the same to static alignment. However, acceleration quantization in MINS will cause velocity error, which will influence the rapidity and accuracy of SINS alignment. This paper analyzes the influence of acceleration quantization error on SINS rapid alignment. Numerical simulations are performed, and the results show that if the quantization frequency of MINS accelerator is 24 KHz, and the correspondent alignment error of SINS is within 0.003° / h, the alignment time can not be less than 300s.

A study for the control algorithm of vibration simulation system using multiple shakers and sensors is presented. The classical multi-shaker control theory and methods are first reviewed, from which the simulation results are given. A modified self-tuning algorithm with controllable convergence behavior is proposed to get better control near the modal frequency of the structure. Some judgment rules are developed to prevent the user from specifying a impossible spectra matrix. To verify the algorithm, a real-time control system using the real-time kernel VxWorks as the algorithm development platform is designed. A series of highly efficient vector and matrix algorithms which is the core of the random vibration control process are achieved. The results of simulations and experiments demonstrate the feasibility of the proposed method.

Collaborative Signal Processing multiagent -based on a for target tracking in wireless sensor network is proposed in this paper. Dynamic coalition is used to perform distributed tracking. When a target occurs in the sensing area, sensor nodes try to form dynamic coalition in each field for fulfilling tasks. Each sensor node, which has incomplete information about its dynamic and uncertain world, must respond to sensed events within time constraints. The aim of Collaborative Signal Processing in wireless sensor network is to insure that all necessary parts of the tasks being dealt with are involved in the operations of at least one sensor node. All sensor nodes must act in a purposeful and consistent manner within the available computational and resource limitations Utilizing multiagent technology can make good use of each sensor nodes' limited energy and perform tasks coordinately.

Controller via Weak Control Lyapunov Function (WCLF) was presented for Newton-Leipnik equation, which has two strange attractors: the upper attractor (UA) and the lower attractor (LA). The final structure of this controller for original stabilization has a variable-structure nonlinear feedback form. Through WCLF principle, three different kinds of chaotic control were investigated, separately: the original control forcing the chaotic motion to settle down to the origin from any arbitrary position of the phase space; the chaotic intra-attractor control for stabilizing the equilibrium points only belonging to the upper chaotic attractor or the lower chaotic one, and the inter-attractor control for compelling the chaotic oscillation from one basin to another one. Both theoretical analysis and simulation results verify the validity of the suggested method.

An identification-free adaptive optimal control based on switching predictive models is proposed for the systems with big inertia, long time delay and multi models. Multi predictive models are set in the identification-free adaptive predictive control, and switched according to the optimal switching instants in control of the switching law along with the system running situations in real time. The switching law is designed based on the most important character parameter of the systems, and the optimal switching instants are computed out with the optimal theory for switched systems. The simulation test results show the proposed method is suitable to the systems, such as superheated steam temperature systems of electric power plants, can provide excellent control performance, improve rejecting disturbance ability and self-adaptability, and has lower demand on the predictive model precision.

In this paper, we consider the estimation of the unknown parameter for the problem of reconstructing a high resolution image from multiple under-sampled, shifted, degraded frames. L-curve criterion is used to estimate regularization parameters. However, the computational of the L-curve is quiet costly for large-size problems. The paper proposes an efficient approximate technique based on Gauss quadrature rule. The technique translates some matrix computation into Gauss quadrature with singular decomposition. It can reduce the computational complexity of the L-curve.

Power system is a kind of typical non-linear system, it is hard to achieve excellent control performance with conventional PID controller under different operating conditions. Fuzzy parameter adaptive PID exciting controller is very efficient to overcome the influence of tiny disturbances, but the performance of the control system will be worsened when operating conditions of the system change greatly or larger disturbances occur. To solve this problem, this article presents a rule adaptive fuzzy control scheme for synchronous generator exciting system. In this scheme the control rule adaptation is implemented by regulating the value of parameter d_i under the given proportional divisors K₁, K₂ and K₃ of fuzzy sets A_i and B_i. This rule adaptive mechanism is constituted by two groups of original rules about the self-generation and self-correction of the control rule. Using two groups of rules, the control rule activated by status 1 and 2 in figure 2 system can be regulated automatically and simultaneously at the time instant k. The results from both theoretical analysis and simulation show that the presented scheme is effective and feasible and possesses good performance.

This paper presents a design procedure for a robust power system stabilizer(RPSS) based on fuzzy logic control techniques. Speed deviation of a synchronous generator and its derivative are chosen as the input signals of RPSS. A normalized sum-squared deviation(NSSD) index is used to design the RPSS and investigate the robustness of the RPSS for a multi-machine power system. Nonlinear simulation tests under different disturbances are given and their results are discussed.

Stewart mechanism is widely used in industry. To study the control of Stewart mechanism, hydraulic Stewart platform was used as plant. Controller was designed according to dynamic model and local closed-loop control system was built. Coefficient matrices of dynamic equation of Stewart platform can only be known by measuring real-time pose of platform and doing real-time calculation, which makes application complicated. Therefore dynamic model was transformed, and one operating point was defined as nominal operating point, where coefficient matrices of dynamic equation were constant. Sliding mode controller was designed with simplified dynamic model, and reaching condition of sliding mode was given in the entire workspace of platform. Hence real-time pose measure is avoided and calculation is reduced. Simulation and experiments show that trajectory tracking performance with payload is improved by use of the proposed controller.

Excitation current and torque current are decoupled through vector control in frequency converter, so the linear control method can be used in speed loop. Pseudo derivative feedback with sub-variable control (PDFSV) has excellent performance and easy to realize. Its control parameters are obtained through present equation which is related to inertia parameter. To the frequency converter system with parameter changes at extensive range, the PDFSV control with variable control coefficient is presented: to construct full-order state observer, to observe the speed error signal which contains error information on the moment of inertia and calculate control coefficient by presented equations, and feed forward the observed load. The simulation results show that the speed control response performance well when the moment of inertia and disturb load varied at extensive range.

In this paper, we propose an algorithm with multiple constraints that can solve anti-ship missile weapon-target assignment problem. Since there are limitations of existing WTA model in the specific circumstance, based on the basic principles of anti-ship missile route planning decision, this paper has carried out analysis on a specific WTA problem that can be used in anti-ship missile combat, with generalization of constraints and application of saturation attack tactics, a new algorithm under multi-target and multi-launch unit condition is proposed. Furthermore, we consider an engagement scenario for practical simulation, result shows that the new algorithm is excellent in computing time and easy to implement, this allocation strategy provides a real-time method solving the problem of WTA in modern war.

Magnetically suspended flywheel (MSFW) for space application requires fault-tolerant and highly adaptive real-time controller. Field programmable gate array (FPGA) offers a flexible platform to develop robust, adaptable systems for space. As a first step, a FPGA-based digital controller with LEON soft core processor subsystem is presented for active magnetic bearing (AMB) of MSFW. Then a prototyping platform is designed to test algorithms and verify system performance. At last, a reconfigurable FPGA-based AMB controller is proposed.

Input current of driving motor has been employed successfully as monitoring the cutting state in manufacturing processes for more than a decade. In vibration tapping, however, the method of on-line monitoring motor electric current has not been reported. In this paper, a tap failure prediction method is proposed to monitor the vibration tapping process using the electrical current signal of the spindle motor. The process of vibration tapping is firstly described. Then the relationship between the torque of vibration tapping and the electric current of motor is investigated by theoretic deducing and experimental measurement. According to those results, a monitoring method of tool's breakage is proposed through monitoring the ratio of the current amplitudes during adjacent vibration tapping periods. Finally, a low frequency vibration tapping system with motor current monitoring is built up using a servo motor B-106B and its driver CR06. The proposed method has been demonstrated with experiment data of vibration tapping in titanic alloys. The result of experiments shows that the method, which can avoid the tool breakage and giving a few error alarms when the threshold of amplitude ratio is 1.2 and there is at least 2 times overrun among 50 adjacent periods, is feasible for tool breakage monitoring in the process of vibration tapping small thread holes.

Measurement of concentration of photosensitizer, tissue oxygen can reveal information about tissue metabolism and effects of photodynamic therapy (PDT). The purpose of this study is to develop a monitoring and auto-controlling laser system for PDT instrument. The concentration of issue oxygen is detected by near-infrared spectroscopy (NIRS). The blood drug level of photosensitizer is monitored during PDT by fluorescence spectroscopy which was induced by 532 nm Laser. The Laser's output power and idle time can be determined by those monitored parameters. Thus, this system will provide insights into ways to enhance treatment's effectiveness and selectivity in clinical operation.

Transfer alignment(TA) filter is used to estimate the relative attitude errors between a slave inertial navigation system(SINS) and a master inertial navigation system(MINS). Hot studies have been done on match methods of rapid TA in recent years. In practice, in addition to system models, the maneuver plans and filter parameters are also very important to TA process. Without the assistant of appropriate maneuver plans and filter parameters, TA models can not reach excellent filtering performance. Therefore, influences of maneuver plans and filter parameters on TA filter and consistent configuration of them are studied in this paper. Based on a 9-state TA match model, maneuver intensity, maneuver durative time, state predicting covariance matrix P0, state noise matrix Q, observing noise matrix R and filter updating rate as well as their consistent configuration are analyzed respectively. Then, the suggestion of consistent configuration of maneuver plans and filter parameters on TA filter is put forward. Simulation shows that under guidance of the suggestion, TA filter reaches an accuracy of less than 2.5' in less than six seconds.

Through introducing application condition of belt conveyor in the modern mining industry, the paper proposed, in the dynamic course of its starting, braking or loading, it would produce moving tension and elastic wave. And analyzed the factors cause the automatic take-up device of belt conveyor vibrating: the take-up device's structure and the elastic wave. Finally the paper proposed the measure to reduce vibration and carried on the modeling and simulation on the tension buffer device.

Research on the synchronization aiming at a kind of complex chaotic system-delayed chaotic system was investigated in this paper. A kind of control algorithm with simple structure and without the limit of topologic isomorphic to the controlled chaos system and the target one is designed under the feasible assumption. The theoretic analysis of the performance of the given controller and the relationship between the controlling error and delayed time are given. On the basis of that, the simulation on the presented control algorithm is carried out, and the simulation results show the validity of the control algorithm.

To improve the measurement precision of the capacitance method for petroleum water content, this paper presents a nonlinear calibration technique based on neural networks. Consider that the traditional BP algorithm has shortcomings of converging slowly and easily trapping a local minimum value, a combination algorithm using particle swarm optimization (PSO) and back propagation (BP) is adopted to train the neural network. It will enable the calibration process with an overall accuracy and a higher converging speed. Simulation results show that this method can effectively eliminate the impact of non-target parameters to the sensor output and has certain project value.

A new algorithmic for strapdown inertial navigation system (SINS) state estimation based on neural networks is introduced. In training strategy, the error vector and its delay are introduced. This error vector is made of the position and velocity difference between the estimations of system and the outputs of GPS. After state prediction and state update, the states of the system are estimated. After off-line training, the network can approach the status switching of SINS and after on-line training, the state estimate precision can be improved further by reducing network output errors. Then the network convergence is discussed. In the end, several simulations with different noise are given. The results show that the neural network state estimator has lower noise sensitivity and better noise immunity than Kalman filter.

Brillouin distributed optical fiber sensing system based on spontaneous Brillouin scattering frequency shift measurement may measure temperature in the optical fiber, due to the dependence of spontaneous Brillouin scattering frequency shift on temperature. In this paper, nonlinear theoretical models of the Brillouin spectrum in the BOTDR temperature sensing system are analyzed. The model parameters are optimized with Levenberg-Marquardt algorithm. By numerical calculation, it is indicated that pseudo-Voigt function can approach approximated the Voigt profile well and quickly.

In this paper a multivariable robust controller design approach of the ACLS is accomplished by using robust loop-shaping techniques. In order to avoid the inefficient way of choosing the weight functions by trial-and-error method, the structured genetic algorithm (SGA) approach is introduced, which is capable of simultaneously searching the orders and coefficients of the pre- and post-compensator for weight matrices. According to this approach, engineers can achieve an ideal loop-shape which lies in an appropriate region relating to the desired performance specifications. The effectiveness of this approach is illustrated by the longitudinal equations of a carrier-based aircraft's motion design example.

The design and implement method for distributed isomeric system, including a configuration of three-level measure and control network based on field bus, Ethernet and Internet, and their communication techniques, is described. The data integration and management technique by using VC++ multithreading programming and data-base WEB accessing technique are also presented. A micro-computer monitoring software based on B/S model developed by database accessing method and ADO technique can realize the equipments' concentrate monitoring and control. The system has functions such as of operation analyzing, data searching, running curve and data statistics, report forms printing, etc. According to the fact that the running data stream is great and uneven, statistics database and historical database were used to manage and store data, and the results show that the system operate conveniently and efficiently.

Data caching is an indispensable part of high-speed data acquisition system, and it makes an important effect on coordinating the speed of data transfer and data processing. In the article, a data caching controller with ping-pong operation is designed after discussion on the features of data transmission with PCI Express interface. The controller's structure and principle is described, as well as the control logic. Additionally, the controller shows the idea of pipeline, where the command sending and data transfer control are separated on controlling the DDR controllers. The result indicates that the design could be widely used in the seamless caching and high-speed data process system. System efficiency will be improved, and the logic design will be simplified.

With the particle swarm optimal (PSO) algorithm, an adaptive fuzzy logic controller (AFC) based on interval fuzzy membership functions is proposed for vehicle non-linear active suspension systems. The interval membership functions (IMFs) are utilized in the AFC design to deal with not only non-linearity and uncertainty caused from irregular road inputs and immeasurable disturbance, but also the potential uncertainty of expert's knowledge and experience. The adaptive strategy is designed to self-tune the active force between the lower bounds and upper bounds of interval fuzzy outputs. A case study based on a quarter active suspension model has demonstrated that the proposed adaptive fuzzy controller significantly outperforms conventional fuzzy controllers of an active suspension and a passive suspension.

In this study, the probability density function (PDF) control method has been developed to deal with the random tracking error for a class of robotic manipulator that are subjected to non-Gaussian noises. The control aim is that the shape of the PDF of the tracking error is made as close as possible to the desired PDF. The ILC frame about PDF control approach of manipulators system with non-Gaussian noises has been proposed and a recursive optimization solution batch-by-batch has been developed. In each batch, nonlinear closed-loop error dynamics is considered. In addition, the convergence condition of the tracking control algorithm has been analyzed. Finally, a simulation is given to illustrate the efficiency of the proposed approach.

In this paper an output regulation design of nonlinear system is applied to solve a tracking problem for a simulated nuclear reactor. A nonlinear observer for state estimation of a nonlinear nuclear reactor system is designed using a Lyapunov function. A nuclear reactor power controller is then designed by using the output feedback using the observed state. Simulations are provided to show the efficiency of the proposed controller with estimated state feedback from the proposed observer.

The mean-wavelength stability of broadband fiber source is analyzed: The model between the mean-wavelength and the pump optical power is revealed based on the theoretical and experimental study on the change of mean-wavelength under different pump optical power. To promote the temperature stability, a mean-wavelength control scheme is proposed based on the relation of mean-wavelength, pumping current and environment temperature. The output power was stabilized with a close-loop control technology by taking a adjustable attenuator. Prototype fiber source was made and tested. The Mean-wavelength stability 0.5×10^-6/°C and output power stability 3% within -45°C ~+70°C was achieved.

As the important index of evaluating the operational sensitivity of the rolling bearings, the friction torque of bearing for space using influences the signal transferring accuracy and the system stability of the spacecraft directly. It is difficult to do the large number of tests based on the particularity of the bearing for space using. Therefore, considering the limitation of the statistical principle, a dynamic evaluation model called the grey bootstrap modeling (GBM) is proposed in the paper to dynamically evaluate the friction torque of bearing for space using. The test shows under the condition of the minimum of the mean uncertainty, choosing the suitable rolling factor, the number of resampling and the confidence level, the GBM can describe the fluctuation interval of the friction torque on-line much better, and also can separate the systematic error. So, the GBM has the better performance of dynamic forecasting and its liability is quite high.

Aimed at the demand of the high precision displacement measurement in high speed magnetic suspended flywheel (MSRW), the variable frequency and amplitude modulation eddy current sensor is analyzed and the sensor's equivalent transfer function is given. A design method of phase-lead network for eddy current sensor lead compensation is proposed. The test result indicates that the sensor bandwidth can reach 10 kHz after phase compensation in high frequency band and the sensor's phase-lag is decreased markedly, the dynamic performance of the sensor is improved effectively. The MSFW experiment indicates that the sensor can supply precision displacement information of flywheel rotor and the MSFW can work at 40000 rpm stably after compensation.

There are mainly two methods to solve the problem of satellite attitude determination: one is state estimation algorithm; the other is deterministic solution. Along with the rapid development of small satellite technology, deterministic solution gains more and more attention due to its small computational cost and fast convergence speed. The article presents Wahba's problem, from which deterministic solution is originated. The situation of two vector measurements is specifically addressed and discussed. Then, the batch attitude determination algorithm is presented. The importance and emphasis will be on the difference and comparison of various solutions. In order to achieve the algorithm in practice, many authors make efforts to extend the solution from point-by-point to recursive algorithms. In addition, necessary extension is carried out to estimate other non-attitude parameters.

High precision, fast computation speed, as well as a good capability of fault tolerant and reconstruction are required more and more for spacecraft attitude determination system. To realize the above requirement, an approach was presented to the synthesis of federated filters using sigma point technique. In this algorithm, the sigma point technique brought the algorithm a high precision, while the federated structure significantly enhanced the filters' capability of multi-rate information fusion, fault tolerance, and system modularity. Within consideration of computation consumption, a simple information-sharing formulation was derived to adapt to the special property of sigma point distribution, and a dynamical information sharing strategy for multi-rate fusion was developed. A numerical simulation example was employed to give the algorithm a test, where the simulated system contained a suit of gyroscopes; a three-axis magnetometer and a sun sensor each had a different sampling time. Simulation results demonstrated the efficiency of the federated sigma point filtering algorithm. It proved a better precision and a faster convergence speed than its traditional counterpart federated EFK, and had the capability of system reconfiguration for fault tolerant.

This paper describes a mini UAV (Unmanned Aerial Vehicle) system for target tracking. The mini UAV system can be divided into two parts: the onboard system and the GCS (Ground Control Station). The former implements the algorithm of autonomous flight. The latter monitors the flight conditions of the mini UAV and displays the video taken from the onboard opto-electronic detector. Accurate heading and trajectory control is needed when tracking the ground targets with the mini UAV, which equipped with roll-only opto-electronic detector. The precision of control is greatly affected by wind. The kinestate of the mini UAV in circular tracking is modeled and analyzed, and the flight control laws are designed and simulated. The simulation results show that the control strategy is easy to be realized and the precision of tracking is satisfying.

It is a valid way to implement some difficult space operations by distributed spacecraft system. Relative Positioning and posing is one of key technologies for distributed spacecraft system. A special algebra of Rodrigues parameters is defined for better description of attitude motion and coordinate transformation. In this paper, on the basis of the theories of Rodrigues parameters, Extended Kalman Filtering (EKF) and the attitude dynamics of spacecraft, a relative positioning and posing algorithm for distributed spacecraft system based-on Rodrigues parameters is proposed. Firstly, state equation is built according to C-W equation and Rodrigues parameters differential equation. Secondly, observation equation is built according to con-line equation of vision navigation. Finally, some simulations are done in order to demonstrate this algorithm. The simulation results show that proposed algorithm is valid for distributed spacecraft system.

To overcome the defects of the present permanent magnet biased radial magnetic bearing, a new type permanent magnet biased radial magnetic bearing in magnetic suspending reaction flywheel application is reported. The fundamental principle of the radial magnetic bearing is presented. And the radial magnetic bearing is analyzed and calculated by using equivalent magnetic circuit and finite element method (FEM). As a matter of fact, the flux of permanent magnet and electromagnetic occur in any radial plane, so the axial length of the radial magnetic bearing will be lessened. Therefore, the presented radial magnetic bearing has smaller volume compared to the existing structure. It is much suitable for magnetic suspending reaction flywheel.

An integrated information system (IIS) which contains strapdown inertial navigation system (SINS), automatic pilot and terminal guidance seeker is proposed. Using rotating modulation approach, the performance of the low cost MEMS inertial sensor is improved by 20-30 times. The precision of the modulated MEMS gyro is available for strapdown navigation system and autopilot. The IIS gyros replace gimbal-based gyros are used in the line-of-sight (LOS) stabilization system. The seeker's LOS angular rate is estimated by combining the missile-fixed gyro information with gimbal coordinate rate information. The indirect LOS stabilization control loop is elaborately designed according to the gimbal kinematical relationship and dynamics models. The study and analysis results show that the compensation torque is available to null the disturbance and make the LOS stabilization. The proposed IIS saves two sets of gyros and make the SINS, autopilot, seeker integrated designing. It owns many advantages such as compact configuration, prominent low cost etc.

Exact knowledge of attitude and azimuth is a fundamental factor in steering vehicle and robot (called carrier in this paper). Micro inertial measurement unit (MIMU), i.e. IMU made by silicon MEMS inertial sensors, GPS and MEMS magnetic compass (MMC), are often used in traditional low-cost attitude and azimuth determination solutions. The main discrepancy, in all of these low-cost approaches, is that the azimuth output is affected by acceleration and turns for long-playing carriers. This paper puts forward a MMC/MIMU/GPS integrated system and an iterative attitude & azimuth determination algorithm for long-playing accelerated carrier's motion. GPS output (.i.e. position and velocity), in ENU (East-North-Upward) navigation frame is transformed into body frame by transformation matrix C^b_n. By integrating the MIMU and GPS measurements, through Kalman Filter (KF), the three orthogonal components of the gravity vector are precisely estimated in body frame despite the acceleration effects. Pitch and roll angles are calculated by gravity vector components in body frame, where as azimuth angle is calculated by combining pitch angle, roll angle and MMC output. The direction cosine matrix C^b_n, updated by the latest azimuth, roll and pitch angles, is used in next round of this iterative attitude & azimuth determination algorithm. CFAR (Constant False Alarm Rate) filters have been utilized to suppress the noise in GPS data caused by differential operation. The proposed iterative algorithm has been practically implemented and simulated. The simulations results prove the ability of the MMC/MIMU/GPS integrated system to determine the attitude and azimuth for long-playing carrier in any motion situation.

Transfer alignment is an initialization of the missile INS prior to launch using data provided by master INS or GPS/INS system in aircraft. Generally, Kalman filter is applied to estimate misalignment attitude. Unfortunately, the Kalman filter provides optimal estimates only if the system model is accurate and filter noise is white and accurately obtained. Considering the complicated vibrated air environment, these demands can not be satisfied all the time. Therefore, after establishing a 12-state velocity matching transfer alignment model, an improved adaptive method is derived on the basis of the study on traditional adaptive Kalman filter such as Sage-Husa and intense adaptive filter. The improved adaptive filter is aimed at modifying the model and noise matrix with the process of filtering according to the practical measurement data. Numerical simulations show that with this improved adaptive filter under a "s" turn maneuver, transfer alignment Kalman filter keeps good working condition under large range of P, Q and R, and reaches good performance on estimating precise and convergent speed.

Strapdown stellar-inertial integrated attitude determination based on low-cost micro-electromechanical system (MEMS) gyroscopes and a complementary metal-oxide-semiconductor transistor active pixel star sensor is one of the most effective methods for nano-spacecrafts attitude determination. However, the accuracy of attitude determination is low because of non-linearity of the system. Thus, an adaptive segmented information fusion method based on the UKF is presented by taking UKF+QUEST and UKF+optimal REQUEST as two modes of information fusion that can be adaptively switched between. Initially, the gyro drift estimation error is inaccurate, and the UKF+QUEST mode is adopted to quickly estimate the gyro drifts. When the mean-square error matrix of the UKF tends to stabilization, the information fusion mode is adaptively switched to the UKF+optimal REQUEST dual-filter model. The hybrid simulation results show this method not only has higher accuracy in attitude determination but also can quickly estimate gyro drifts.

In this paper, a reduced-order observer is applied to fault diagnosis for reaction flywheels in satellite attitude control system. The benefit of this approach is able to estimate the fault signal of reaction flywheel in the presence of unknown inputs. Through ingenious state transformation, the original system is decomposed into two subsystems, one of which is driven by known inputs only. Thus, after a reduced-order observer being designed, the subsystem's accurate state estimation can be obtained without the effect of unknown inputs, consequently, the unknown inputs can be estimated. In this case the fault signals of reaction flywheels may come down to a part of unknown inputs, then the faults can be detected according to the estimated unknown inputs.

Nano-satellite is a kind of advanced and effective tool for space exploration. And the nano-satellite formation flight technology becomes more and more important in distributed space exploration. Thus a design of high performance management and control system (named MCS) of nano-satellite for formation space exploration is presented in this paper. Different with traditional design concept for satellites, MCS adopts a modular configuration not only to satisfy composite requirements of processing capacity, integration, cost and power of nano-satellite, but also to fit applications in formation flight experimentation. MCS includes OBC (on-board computer) module, attitude & orbit control module, telemetry & telecommand module, and power management module. Furthermore, as core component the design uses reconfiguration scheme and COTS (commercial-off-the-shelf) technology, so it shows an outstanding performance in high efficiency, high reliability, low power and low cost for satellite engineering applications.

Geomagnetic field is the basic physics field of the Earth, which can't be destroyed or changed in the foreseeable future. Geomagnetic field don't require special service, therefore, it can be considered as a solid source of navigation information. The key technologies of geomagnetic navigation are still looking for high accuracy mapping and high accuracy geomagnetic field measurement on board aircraft, this paper special attention is paid to the data grid interpolation methods, the absolute accuracy of the interpolation methods are analyzed by comparing interpolation point with the actual surveyed point, and the geomagnetic map grid interpolation methods can be evaluated impersonally by residuals analysis. The results show that Radial Basis Function Method has little standard error, little average deviations and little standard deviations, and it has little "bull's-eyes" in the geomagnetic map.

It is very important to accurately detect rotor position and speed in brushless direct current motor (BLDCM). Aiming at BLDCM which drives the magnetic suspended reaction flywheel (MSRFW), a novel scheme to estimate the low speed of the BLDCM based on Hall sensors and Kalmam fliter is presented. The average speed over the previous sector is achieved according to the outputs of the three hall sensors, then rotor position of the next sector is computed at the sampling time. The electrical angle calculated can be used to estimate the transient speed with Kalman filter equation. Simulation and experiment show that the proposed method is valid.

GPS technology has been developing rapidly in the last 10 years. GPS has also embodied its distinguished magnificence in scientific research, such as 'GNSS-R Oceanographic Remote Sensing', in addition to being an equipment of navigation and positioning. The development of GPS application places an increasingly high demand on the capacity of GPS receiver. Compared with the traditional GPS hardware receiver, GPS software receiver is featured by its expansiveness, convenience and flexibility etc., so it is suitable for research and development of various sophisticated algorithm. GPS software receiver has attracted enthusiasm of numerous research institutions in recent years. This paper focuses on the design, construction and validation of a GPS L1 bistatic radar software receiver for GNSS-R remote sensing purposes. The requirements of the acquisition process of weak signal are analyzed. And the principle and implementation of code and carrier tracking are proposed. Finally, a test result is presented.

The space solar EUV and X ray imaging camera is the core of the solar EUV and X ray imaging telescope, which is designed to monitor and predict solar activities, such as CMEs, flare and coronal hole. This paper presents a comprehensive description of the camera, from the detector selection to the electronics system design, and gives some experiment results. The camera adopts a back illuminated X ray sensible CCD as detector and the support electronics is based on it. The electronics system should be designed according to the CCD structure. This article gives an illustration of the three modules and a software in electronics system, and offers possible solutions to some common problems in CCD camera designing. There are detailed descriptions about drivers and signal amplifing and processing Module.

A micro-satellite, Yinghuo-1, would be launched with Russian spacecraft, Phobos-Grunt in October, 2009 to investigate the space environment around Mars. YH-1 and Phobos-Grunt forms a two-point measurement configuration in the Martian space environment. YH-1 and Phobos-Grunt are equipped with similar magnetic field and plasma detecting payload on two spacecraft would give some coordinated exploration around Mars. YH-1 would orbit Mars with periapsis of 800 km above the Martian surface, and apoapsis about 80000km to the center of Mars. The orbit inclination is in the range of 0~7° to the Martian equator. A flux-gate type magnetometer, with two tri-axial sensors, is developed for YH-1 spacecraft. Two sensors are mounted on one-side of the deployable solar panel with a radial separation about 45cm to function as a gradiometer to minimize the affects of platform remanence. The dynamic range of the magnetometer is ±256nT with a 16-bit ADC converter, and the noise level is better than 0.01nT/√Hz, to measure three-component magnetic field from DC to 10Hz. Flux-gate magnetometer would work together with the Plasma Package onboard of YH-1 to investigate the Martian bow shock, magnetosheath, magnetic pileup region (MPR). A detail description of the flux-gate magnetometer is presented in this paper, with test and calibration results.

This paper introduces a new high energy particle detector (Space Environment Monitor) which integrates high energy electrons' and protons' direction detection and high energy particles' spectrum and flux measurement. Also it briefly explains this detector's science goals, structure design and electronic design, and then indicates its innovations and pivotal

The Sino-Russian Joint Mars-Phobos Exploration program provides unique opportunity to investigate the global structure of the solar wind/Mars interaction region. The Mars orbiter YH-1 will carry a plasma package consisting of two identical ion detectors, and one electron detector, which is aimed at monitoring the plasma with energy up to a few keV in the environment of the planet, provides a mass analysis of the ions in the mass range form 1 to 44 au. Together with the magnetic field experiment on board YH-1, the plasma package will be the first to give full insight into the local plasma characteristics near the planet, as well as to determine the possible the total ion escape (particles/s) for the major ion species.

High energy electron particle detector on FY2 satellite has the capabilities to observe ≥0.2MeV electrons. Based on the high energy particle detector on FY2D satellite, this detector assumes some new design to detect particles more accurately, and it has higher reliability. This paper gives some information about the high energy electron particle detector on FY2.

This paper describes a GPS signal acquisition method using FIR decimation filter and FFT. First, FIR decimation filter was used to decimate the digital IF signal after the carrier wipe-off. Then, the C/A code phase and carrier frequency was determined through the processing of FFT-based acquisition method. Finally, the Gaussian noise was added to the digital IF signal to analyze the performance of noise immunity. The model of system simulation was provided and the performances of this method compared with conventional FFT-based acquisition and averaging correlation method was analyzed. The simulation results show that acquisition with FIR decimation filter, compared with FFT-based acquisition without decimation, can reduce computational complexity and speed up the signal acquisition processing, while the max correlation value descends about 10%. Compared with averaging correlation acquisition method, the max correlation value between the received signal and the local C/A code can be improved by an average of 30%. Moreover, this acquisition method has a better performance of noise immunity than other two methods.

A number of recent and proposed joint UK and China space missions have provided the opportunity for cooperation on space instrumentation and data systems. In particular, the joint ESA-CNSA Double Star mission allowed a modified implementation of the fluxgate magnetometer (FGM) designed for the ESA Cluster mission and a fast energetic particle instrument is in development, anticipating Kuafu and other possible future missions, which allows full 3-D measurements of the particle distribution in the nominal energy range from about 20keV to about 1 MeV to be made at high time resolution (~0.4 sec) using a wide FOV modular design. The development of the particle instrumentation includes design options which allow combined operation with other high energy particle instruments. Low mass versions are possible and may be considered as part of the payload for small satellite missions.