To suppress the imbalance force in magnetically suspended rotor systems, an autobalancing control strategy based on a plural phase-shift notch filter and feedforward control method was proposed. The structure and working principle of a suspended rotor system were introduce, and a model of the magnetically suspended rotor system with rotor imbalance was described. The electrical characteristic of the imbalance force was analyzed. Then, the condition to suppress the imbalance force was calculated and the result shows that the suppression errors are mainly caused by the amplitude error and phase error from power amplifiers. By transforming the two degrees-of-freedom translational motions into a single degree-of-freedom plural equation, a plural phase-shift notch filter was proposed. Its math equations were formulated, and the notch features of the amplitude and phase were discussed. Finally, the proposed strategy was tested and verified on a magnetically suspended control moment gyro test platform. The experimental results indicate that the imbalance force has been suppressed by 94.2% with the proposed strategy, which verifies the effectiveness of the proposed control strategy. Moreover, the proposed control strategy is characterized by smooth dynamic processing and a light computational load.

A calibration method suitable for a laser probe in on-machine laser scanning measurement was proposed to eliminate the measuring errors from installation pose. A prototype system for the on-machine laser scanning measurement was built and a model of the laser probe moved with a machine tool was established. The center of a standard ball was fitted by scanning the ball surface with multi-perspective, and a linear algorithm to solve the installation pose parameters of the laser probe was given to overcome the heavy computation and un-robustness of the existing nonlinear algorithms. The influence of the machine tool movement error on the measurement was also analyzed and an error model was established and a compensation method for the machine tool error was proposed. The experimental results show when the standard ball with a known diameter was measured, its diameter error measured by the laser probe at different angles is less than 0.05 mm, and the position error of the standard ball center is reduced by 83% with the compensation method. The results illustrate the feasibility of the calibration method as well as the validity of the error model and the compensation method.

On the basis of the advantages of photo-elastic modulation, a phase-modulated ellipsometry combined a photo-elastic modulator with an electro-optic modulator is proposed. It uses one single detection light path to obtain the signals.By switching two work conditions of the electro-optic modulator, it takes lock-in signal processing technology to solve out the two ellipsometric parameters, amplitude ratio Ψ and phase difference Δ, from the p component and s component of reflection light of a simple. The principle of the new type of ellipsometry is analyzed, and a principle prototype is set up. The relationship between the peak value of modulated voltage and the phase modulation amplitude of the photo-elastic modulator is calibrated, and the calibration result is better than 99.95%. Then, an instrument offset method is used to calibrate the experimental system. Finally, a quartz glass reflective sample is analyzed by using this system, and the measurement accuracy of the Ψ and Δ are respectively better than 0.08° and 0.81°. The experimental results show that the instrument offset method effectively eliminates the detection errors introduced by the residual birefringence of the photo-elastic modulator and electro-optic modulator, and the data acquisition time and signals processing time are in the order of the millisecond. In conclusion, this phase-modulated ellipsometry proposed has potential advantages of wide spectrum measurement, stable operation, high repetition rate, fast measurement speed, low cost, and is conducive to industrial automation integration.

The principles of optical Modulation Transfer Function(MTF) measurement by the edge method for an optical system were researched and an improved inclined edge method for the MTF measurement of an infrared imaging system was proposed. As the edge angle measurement error and noise will cause the MTF measurement error of the infrared system, the Canny operator, line fitting and Edge Spread Function (ESF) reconstruction row number changes were combined to improve the measuring accuracy of the MTF, meanwhile, an effective denoise algorithm for the ESF and the Line Spread Function (LSF)was used to reduce the effect of noise on the MTF measuring accuracy.With the methods mentioned above, the measurement errors of MTF were reduced systematically. An experimental platform was set up. Based on the theoretical model of infrared imaging system and MTF curve obtained by detected parameters, the feasibility of the proposed method was verified and the effect of changed edge angle on the MFT measuring accuracy was analyzed. Experimental results show that the measurement accuracy of MTF curve obtained by the method is 0.010, the measuring repeat accuracy is 0.008, and the edge angle should be kept between 2 °and 10 °. It concludes that the method effectively reduces the influences of the edge angle measurement error and noise on the MTF measurement, and the measuring results show good measurement repeatability.

To properly evaluate the experimental state of a scramjet engine, the Spontaneous Raman scattering technique was used to measure the main species in flow field of the scramjet engine. According to the engine experimental conditions and the interface of engine and optical diagnosis, a spontaneous Raman scattering experimental system for the engine flow field diagnosis was established. Then, the Raman spectra of the major species in the flow field of scramjet experiment were measured. Finally, the concentration of the major species was obtained by analyzing the Raman spectra, and the oxygen content of the incoming flow was emphatically analyzed. The results show that the maximum oxygen content and minimum oxygen content are 30% and 18% respectively in the incoming flow after oxygen supplementation. It means that the control precision and stability of oxygen supplementation in the scramjet experiment should be improved. The results also demonstrate that spontaneous Raman scattering technique works well for the species concentration measurements in the flow field, and obtained measurement results can be utilized for the analysis of scramjet experimental data and the improvement of the control method and control accuracy of oxygen supplementation for the incoming flow.

A visual metrological method based on a two-parallel-plane camera model is proposed for the measurement of the sizes of moving steel plates on production lines. This method uses a data driven mode to calculate the world coordinates of any image point's corresponding projective point on the calibration plane. A k Near Neighbour(k-NN) algorithm is presented to generate the distortion free projective image on the calibration plane from the original image and to build a direct connection between the image and the world coordinate system. An optical center localization algorithm is also proposed. The metrological method uses line structured light to realize the thickness measurement. Then, it extracts plate's edge lines from the distortion free projective image by using their parallel or perpendicular properties and calculates the size of the plate from the edge lines' equations in the world coordinate system. Finally, a framework of large scale steel plate size measurement system is given. The above method is a monocular visual metrology. As comparing to other methods, the method is characterized by simple mounting and smaller calibration process. Experiments results show that if a camera with an image resolution of 640×480 is used to measure a standard 80 mm×50 mm×15 mm aluminum cuboid via the method, the thickness error is 0.1 mm, and the length and width errors are both less than 0.2 mm. When the method is applied to real steel plate measurement, the measurement accuracy is higher than manufacture accuracy, which shows that it satisfies the demands of product measurement.

To guarantee the demand of an underwater vehicle in sailing for the optical concealment in the visible light band and to measure the optical concealment depth of the underwater vehicle in real time, a miniature optical concealment depth measuring system for the visible light band was designed. Due to a model for optical concealment depth, the measuring methods for seawater upward irradiance, seawater downwelling irradiance, the diffuse attenuation coefficient of sea water, and sea water body attenuation coefficient were designed optimally. After optimization, the system has 21 measuring channels with the measurement spectral range from 390 nm to 667 nm, and working depth up to 50 m. A test on the sea was performed, and the test results show that there is an exposure window in the visible light range of 520-560 nm for the underwater vehicle under good weather conditions, meanwhile, the optical concealment depth of the underwater model with a feature length of 0.75 m is 3.5 m. The test results indicate that the miniaturization design of the optical concealment depth measuring system realizes the measurement of the optical concealment depth in the visible light band. The measuring device has advantages on small size and light weight and the system is stable for carrying on the underwater vehicle and provides theoretical and technical supports for the design of the optical concealment depth measuring system which can be independently lifted.

The principle of on-board calibration for a solar diffuser was expounded, and a method to monitor the degeneration of the solar diffuser was researched. A Solar Diffuser Degeneration Monitor(SDDM) was designed to monitor the degeneration of Bidirectional Reflectance Distribution Function(BRDF) of the solar diffuser by measuring the ratio of the reflected radiance of solar diffuser to sun irradiance. The relationship between on-board calibration and the monitor of the solar diffuser was described. An integrating sphere with two light imports and a baffle for the SDDM was designed to eliminate the dependence of the changed incident angles on the detector response. According to the monitor process, the physics models of SDDM were given, and the dynamic range and Signal to Noise Ratio(SNR) of detectors in the SDDM were validated and analyzed. Finally, the illumination of the sun on the SDDM was simulated in a lab to test the transmittance model repeatedly for several times. By analysis of the measurement uncertainty related to the Bidirectional Reflectance Factor(BRF) of the solar diffuser, satellite attitude and the mounting error of the SDDM, it shows that the monitoring uncertainty of the solar diffuser is better than 0.88%.

For the manufacture of a lithographic lens with a 45 nm node, this paper focuses on the development of high numerical aperture (NA), deep ultraviolet (DUV) immersion lithographic lenses. Firstly, an off-axis three mirror projection lithographic objective with the NA of 1.30 and a coaxial two mirror projection lithographic objective with the NA of 1.35 were designed. Two design methods and results were compared and the latter was chosen to be used final design. Then, the relationship between variable stop aperture and telecentricity under different NAs was analyzed. A scheme of dual variable curved apertures was proposed to reduce the image telecentricity of a lithographic lens. The final results show that both wavefront errors(Root Mean Square , RMS) and distortion of the lithographic lens are less than 1 nm by using the proposed scheme. The new scheme with dual variable curved apertures makes the maximum telecentricity decreases from 5.83-17.57 mrad to 0.26-3.21 mrad when NA varies from 0.85 to 1.35. This scheme provides an advantageous theoretical guidance and basis for research and development of the lithographic lens with 45 nm node.

As the strain transfer theory of existing Fiber Bragg Grating(FBG) sensors does not take its effect on basic material strain into account, this paper researches the strain transfer theory for a FBG sensor bonded on a plate. The strain of an optical fiber is different from that of the plate, so the strain relationship between the optical fiber and the plate was studied to improve the measurement accuracy of FBG sensors. A theoretical model of strain transfer of FBG sensors bonded on the plate was presented, and the interaction between the FBG sensor and the plate was analyzed. Then the theoretical predictions were validated by Finite Element Method(FEM) and experimental data. Finally, the effect of the parameters of the plate on the strain transfer rate was analyzed. The results show that the error between the FEM and theoretical solution has controlled within 4% and that between the FEA and experimental data has controlled within 5%. Moreover, the strain transfer rate increases with the increases of both thickness and Young's modulus of the plate. It concludes that the theoretical model satisfies the accuracy requirement of the FBG sensors, and could provide a design reference for the FBG sensors.

Traditional detecting methods for plastic optical lenses are complicated to operate and very time-consuming. Therefore, a new detection method based on the magnetic levitation theory was proposed for a small plastic lens and a corresponding detection device was designed in this paper. With the detection method, the diamagnetic sample (plastic lens) in the magnetic field of paramagnetic solution was levitated by magnetizing the solution. By observing the height, the centre position and the deflection of the lens in the device, the appearance and interior homogeneity like shrinkage and internal porosity of the lens could be detected. Several experiments on the qualified lenses, the lenses with an incomplete appearance or with interior homogeneity and some of disqualified lenses were performed for verifying the feasibility of the proposed method. The experimental results show that the proposed method is precise sensitive, easy to operate and has wider application fields. The detecting accuracy for density reaches to 0.003 g/cm3 under a millimeter scale. Moreover, the method detects the interior porosity of the lens with a diameter less than 10 mm and the sensitivity to the volume of the porosity reaches to 0.017 mm3. The proposed method has great potential for plastic optical lens detection.

To improve the wavefront detection accuracy of a liquid crystal adaptive optical system, a correction method for the Tip/Tilt Mirror(TTM) in the liquid crystal adaptive optical system was researched. The physical characteristics of each ingredient in the adaptive optical system were analyzed, and the basic structure of the TTM model was given based on the Lagrange equation. Then, the model parameters were acquired by using modified subspace identification method, and the frequency domain characteristics of a subspace model were corrected by nonlinear least squares algorithm. After correction, the transfer function precisions are 0.024 5 dB for the amplitude and 1.900 8° for the phase in middle and low frequency domains. Furthermore, Smith predictor was introduced to solve the time delay problem during TTM correction. The model obtained by space identification was used in the simulation and experimental verification by Smith and PID . The experiment result is coincided with simulation result. It is shown that PID with the Smith predictor is superior to traditional PID, and the error residual bandwidth of Smith predictor is enhanced by 23.97% as compared with that of the traditional PID. Finally, a signal of turbulence Tip/Tilt was generated for a correction experiment, and the experimental result shows that the control precision of PID with Smith predictor is improved by 21.03% compared with that of traditional PID, which verifies that the proposed method optimizes the correction accuracy of the TTM and ensures the wavefront detection accuracy of the liquid crystal adaptive optical system.

An innovated pre-sintering process including three-step bubble removing procedure and a micro composite bonding structure containing two micro grooves and one micro block bulge were investigated to effectively suppress the formation of voids in a glass frit layer and to precisely control the bonding gap. The three-step bubble removing procedure includes glass liquid forming, bubble removal in vacuum and void filling-up in air, which effectively removes the bubbles and suppress the generation of micro voids in the intermediate bonding layer. The innovated pre-sintering process shows good repeatability and robustness. The inside and outside micro grooves of the micro composite bonding structure were designed to effectively control the flowing path of the redundant molten glass frit to prevent the sealed micro structure from being polluted. And the micro block bulge was invented to make the thickness of the glass frit be precisely equal to the height of the bulge. The bonding performance testing result shows that the scheme is simple and feasible. Both bonding strength and hermeticity are good. The bonding gap is controlled to be 10.1 μm , the bonding strength is 19.07 MPa, and the leak rate is less than 5×10-9 Pa·m3/s.

As surface texturing technology can significantly improve the friction and wear properties of mechanical components and can extend its lifespan, this paper proposes a technology to rapidly form micro-pores on the metal surface by grinding and polishing method. This technology is characterized by carrying molding process and polishing process simultaneously. By choosing a load of 0.0232 MPa, slurry concentration of 9%, polishing rate of 2.09m/s and an abrasive grain diameter of 0.5μm as the investigation conditions, the formation mechanism of micro-pores on the metal surface is researched. It confirms that the surface micro-pores are formed by the vortex flow motion of the abrasive particles in surface micro defects and the rotation of work component allowing the abrasive particles to grind the wall of defects in turn in the direction of 360°. Moreover, the rounding of micro-pore formed by this technology is arc transition without projections and glitch, which does not require further polishing. By the proposed technology, secondary pores can be formed to extend the specific surface area of the work component under certain texturing condition. In addition, a large amount of micron and sub-micron pores are formed on the surfaces of work components by selecting proper grinding time and texturing condition, which provides a new direction for decreasing the internal film stress and improving interface bonding strength of Diamond-like Carbon (DLC). This study indicates that the micro-pore texturing technology on grinding and polishing shows the characteristics of simple device, high efficiency as well as large area and multi-material textures adapted.

To compensate the offset from optimal focal plane position of a space camera due to its complicated launch environment and space operating environment, a new high-precision focusing mechanism was proposed. The mechanism is driven by equal output components, transmitted by a positive and negative slider-crank mechanisms and its guiding is completed by a direct-acting component. The structural composition and motion mechanism were introduced and its error sources and influence factors were analyzed. The focusing mechanism was supported by the direct-acting component with two points and the output force of each point was equivalence, so that it has no synchronization motion error, and characterized by low internal stress in the organization and high swing angle precision. Furthermore, the gap relieving by preload was used in all kinematics pairs to eliminate the error of back lash in the focusing mechanism to improve focusing accuracy. The test parameter was tested in a simulated space environment, and the analysis and experiment results show that the focusing range of the focusing mechanism is ± 1.7 7 mm, the linear position precision and repeatability are better than ±8 μm and ±2 μm respectively, the synchronization motion error is less than ±4 μm, and the repeatability better than ±1″. In focusing travel ranges, the tilt angle accuracy of the focusing mirror and its repeatability are better than ± 5 ″ and ±1.5″, respectively. These results meet the needs of complex spatial imaging environments.

A two-dimensional parallel micro-displacement stage was designed based on double compound parallelogram flexures to solve the shortcomings of the stage in smaller motion strokes, larger coupling errors, and the motion performance sensitive to manufacturing errors. The designed micro-displacement stage was driven by two voice coil motors in each direction, the coupling motion errors caused by manufacturing errors were compensated by tuning the ratio of the signals imposed on the two drivers and the motion decouplings for X direction and Y direction was implemented. By which, the dependence of the system on manufacturing errors was reduced. On the basis of the Castigliano's second theorem, a model of stage mechanism was established to optimize the size parameters of the stage, and the performance of the designed stage was verified by finite element analysis. Finally, an experimental platform for the micro-displacement position was established. The experimental results demonstrate that the designed stage has a bigger stage stroke, a bigger area ratio (workspace size to planar dimension of the stage ), higher position accuracy, and excellent decoupling performance. It shows a large motion range of ±2.25 mm×±2.27 mm, an area ratio of 1.73%, and the coupling error of less than 0.27%.

Kinematic and dynamic modeling of piezoelectric displacement amplifying mechanisms was researched. The static analytical models(such as displacement amplifying ratio) for a bridge type compliant displacement amplifying mechanism was derived based on the law of conservation of energy and elastic beam theory. Then, an analytical model of natural frequency was also built by employing the Lagrange equation. The finite element analysis was used for verification of the feasibility and superiority of proposed analytical models and for comparison with several typical mathematical models deduced by other authors. The results show that the proposed theoretical formula of the displacement amplification ratio has the highest accuracy, because it considers both the translational and rotational stiffnesses of the mechanism during modeling and abandons the approximate geometric relationship between input and output displacements of the bridge-type compliant mechanism. Moreover, the discrepancy between the theoretical formula of natural frequency in this paper and the finite element calculation results is kept within 5%. The modeling method and corresponding theoretical formulas of the displacement amplification ratio and natural frequency proposed in this paper provides a useful and accurate reference for optimal designing and manufacturing of satisfactory structures of bridge-type displacement amplification mechanisms.

To reduce the grating groove errors caused by the inclination of a grating ruling platform in the fabrication of diffractive gratings this paper proposes a real-time leveling device for the grating ruling platform based on image clarity measurement and electrically adjusting a tilting table. A physical model was built based on the inclination relations between the image clarity measuring and the inclination angle of grating ruling platform. Based on the model, the leveling device could control the grating ruling platform to implement the closed loop dynamic leveling within a certain range. The above theory was verified by tests. The results show that the leveling device is simple and feasible. For a grating blank with a size of 50 mm×50 mm, it controls the inclination of the grating ruling platform to be within 4″, meeting the requirements of the grating ruling for platform positioning accuracy. Moreover, the leveling device can be used in leveling before ruling and also in ruling processing in real time.

As geometric errors of rotary axes of a five-axis machine impact on its machining accuracy, the on-machine measurement of rotary axes and their error modeling were investigated. Firstly, the measurement method for comprehensive errors of rotary axes was presented based on a standard ball and an on-machine measurement system. The measurement angular positions of the rotation axes were planned by the random Hammersely sequence and the initial position of the standard ball was determined with a free installation strategy. Then, a Radial Basis Function (RBF) neural network model for predicting comprehensive errors of the rotary axes was built based on subtractive clustering and Fuzzy C-means(FCM) cluster. Finally, mathematical analysis was carried out to provide a new way to model accurately for geometric errors of rotary axes. A cambered measuring example was used to verify the proposed on-machine measurement method and modeling method.The experimental results indicate that the average deviation between the predicted points from the mathematics model and measured points is 9.6 μm and the maximum deviation is not more than 15 μm. After the measuring results are corrected by the mathematic model with a 3D coordinate measuring machine established by this paper, the average value is reduced to 13.6 μm from 33.5 μm and the maximum value is reduced to 18.6 μm from 62.3 μm. It concludes that the measurement method is simple to operate and has high automation. The neural network's training is not only fast speed, adaptable and good robust, but also can meet highly linear and strongly coupling of modeling of the geometric errors of rotary axes.

To improve the real-time detecting precision of the wear depth for spherical plain bearing testers, a self-made spherical plain bearing tester was selected as studied objective, and its wear depth detecting system was analyzed and molded. The testing principle of the wear depth of the spherical plain bearing was introduced and the error factors affecting the wear-depth detecting precision were analyzed. Then, a comprehensive error model of the wear-depth detecting system for the spherical plain bearing was built by the multi-body system theory(MBS). In addition, the loading deformation of the wear-depth detecting system caused by the varying loading was detected. Finally, according to the above experimental parameters, the loading deformation of the related parts of the comprehensive error model was calculated by Finite Element Method(FEM). By comparison, the maximum difference between the experimental results and the calculated values is 0.028 mm, and the minimum difference is 0.012 mm. On the whole, these values are closer, which verify the correctness of the comprehensive error model under the loading error experimental conditions.

A gas-liquid-solid three-phase abrasive flow finishing method was proposed to improve the efficiency of fluid-based finishing for large-scale workpieces. By introducing micro-nano bubbles into a restrain flow field, the method utilized the energy released by the bubble collapsing to accelerate the motions of abrasive particles and to improve the finishing efficiency. During the finishing process, the fluid viscosity might decline owing to the centrifugal pump heat, and it could influence the amplitudes and profiles of turbulent kinetic energy and dynamic pressure in the near-wall region. Furthermore, the turbulent kinetic energy and dynamic pressure of near-wall region have a major impact on the uniformity of the surface texture and the removal efficiency. On the basis of the results mentioned above, a method to change the inlet velocity to compensate the temperature rising brought by the turbulent kinetic energy and dynamic pressure changes was proposed, and the optimal inlet velocity of finishing fluid temperature from 20℃ to 60℃ between the corresponding nine equal points was obtained. Experimental results show that the gas-liquid-solid three-phase abrasive flow finishing method improves the efficiency respect to traditional methods without the bubble processing, and the inlet velocity compensation improves the quality of workpiece surfaces significantly.

A fast recognition algorithm based on the geometric characteristics of a target was proposed to pursue the fast and accurate recognition for the spacecraft target. In the algorithm, a target incorporated with linear and circular patterns was designed to facilitate the accurate recognition. The noises in the images were reduced by mean of a Gaussian filter. The object edges were detected by Canny operator and the sequences of edges were obtained by the single pixel tracking method. Then, the non-circular edges were excluded according to whether the four non-collinear points were located on the same circle or not and the circle detection was implemented by the geometrical property that two different arcs on the same circle have the same center and radius. Finally, the interruption was eliminated by the geometric relation between target circle and line, and the target was recognized precisely. The experimental results demonstrate that the algorithm is insensitive to noise, illumination and target rotation and efficiently recognizes the target in the complex scenes. Moreover, the processing time is less than 125 ms, which meets the requirement of real-time pose measurement of 8 frames. The algorithm has been used in an engineering prototype successfully, now.

A spatial consistency measurement method based on the Weighted Spatial-Spectral Distance(WSSD) is proposed and applied to the K Nearest Neighbor(KNN) classifier, and a new hyperspectral image classification algorithm is obtained. On the basis of the physical characters of hyperspectral images, the proposed algorithm combines both spatial window and spectral factor to obtain the spatial information and spectral information , and uses the spatial nearest points to reconstruct the center point and to reveal the local spatial structure. With effectively reducing the redundant information in the image, this algorithm increases the consistency of the same kinds pixels and the difference of the different kinds pixels and obtains extract discriminating features, so it implements the consistency measurement between the data points. The experiments were performed on the Indian Pines and PaviaU hyperspectral data sets. Experiment results show that the WSSD-KNN algorithm has better classification accuracy than other algorithms when it is applied to the classification of hyperspectral image, and the overall classification accuracies reach 91.72% and 96.56%, respectively. With the spectral information, spatial information and extract discriminating features, the proposed algorithm effectively improves ground object classification accuracy of hyperspectral data and has better recognition ability in less train samples.

To automatically and continuously estimate the 6-DOF pose of industry parts with a monocular camera, three related problems, building an off-line template library, image processing, and optimizing match, were researched. Firstly, the matching templates under different orientations were established by the CAD model in a STL(Standard Template Library)format, and a new pose parameter was defined to provide the call for a template library. Then, Chamfer Matching method was improved and the sensitivity of fitness function was improved without more time spending by layering the distance mapping map and matching the angle of template searching points. Finally, simulated annealing algorithm together with genetic algorithm was applied to the optimum searching to improve the matching efficiency in real time. The experiment result indicates that the whole match progress spends less than 500 ms, and the correct results are obtained. The translation error and the depth direct error have been kept by less than 1 mm and 2 mm respectively, and the rotate error is about 1° in a viewing distance of 330 mm. The result satisfies the requirements of the monocular vision system for rapid and automatic pose estimation.

An adaptive image dehazing algorithm based on global dark channel prior was proposed to solve the invalidation of original dark channel prior algorithm in bright areas and problems of block effect, Halo effect and higher computational complexity. In this method, the blocking operation was substituted by a global dark channel operation, and the fuzzy logic controller was used to estimate adaptively the threshold of bright areas and the adjustment factor of transmission. After the atmospheric light was estimated in non-bright areas, the miscalculated transmission in bright areas was corrected according to the adaptive tolerance. The algorithm was compared with three kinds of image restoration dehazing algorithms. Experiment results show that the algorithm shows a good subjective visual effect for dehazing images, and the objective evaluation criteria, image contrast, information entropy and average gradient are also superior in performance to those of the other algorithms compared. It concludes that the presented method effectively eliminates the distortion in bright areas and solve the above problems caused by blocking, and the visibility of dehazing image and the operating efficiency have been enhanced significantly.

The wave back restoration of space object images is usually performed by restoration methods for nature optical images, however, the restoration effect is not ideal. This article proposes a restoration model of a space object image based on non-convex sparsity regularization according to the approximate sparsity of the space object image and the features that the gray value submits to Hyper-Laplace distribution in a regularization way. With the alternating direction multiplier method, the restoration model is split into two sub-problems in the numerical solving process: Fast Fourier transformation is used to solve the convex sub-problem, while the fixed-point iteration is used to solve the nonconvex sub-problem. Then, it gives a complete process for the proposed wave back restoration method of space object images, and do an experiment to test and verify the simulated images and the real space object images. Compared results show that proposed method improves the largest peak signal to noise ratio by 2 dB, the average structural similarity by 0.17 and the information entropy and the image definition by 3.85 and 2.65, respectively.

A new method to simulate and test the closed-loop performance of an IR imaging seeker by using digital image injection was proposed. The detector of IR imaging seeker was replaced by image emulation and injection devices in the simulation condition, so the performance of tracking servo loop was likely to be different from that under the actual condition. To allow the results of the digital image injection to be close the simulation experiment, an evaluation index system and an evaluation method for the consistency capability of the tracking servo loop under the simulation test and an actual condition were established to improving the precision and reliability of simulation test result. Then, the accurate tracking servo system model of an actual IR imaging seeker was setup, and a hardware-in-the-loop simulation test system of digital image injection system was established. The experiments was performed on a seeker platform and the capability limits of the hardware-in-the-loop simulation test of digital image injection system was found by adopting the simulation and modeling combined with the experimental test method. The result shows that the tracking performance of the seeker can be held in consistency under the above two conditions when the maximum random maladjustment angle error is 0.18°, the maladjustment angle delay and the maximum angle velocity of the target are smaller than 73 ms and 1(°)/Hz, respectively. These results provide a foundation for forming the capability of the digital image injection simulation test for infrared imaging guidance weapons.

In consideration of the effect of lens distortion on the measuring accuracy of a camera, a lens distortion calibration method based on two view geometry of a translation motion was presented in this paper. The main types of lens distortion affecting the measurement accuracy were analyzed, and a nonlinear distortion model was established. Then, four group equations were established for solving distortion parameters by using the inherent characteristics of projective and two view geometries. Finally, to solve the problem that the small pattern can not effectively be full of the field of view (FOV) in a large range measurement, a calibration processing of distortion parameters by acquiring multi-groups' translation motion images in sub-regional FOV was put forward, by which the calibration of the distortion parameters was implemented in a large FOV by the small pattern. The feasibility of the calibration method was verified by a library, and the results show that the calibration precision of proposed method is higher and the straightness error has reduced by 89%. The calibration accuracy and reliability of this method meet the requirements of visual measurement.

A multi-scale wavelet edge extraction algorithm and Principal Component Analysis-Back Propagation(PCA-BP) neural network classification model were proposed based on magneto-optical imaging to detect the welded defects such as sags, insufficient fusion on subsurface and welding misalignment. The visualization of detection and the classification of welded defects on the surface and subsurface of weldments were explored. Firstly, the weldments were magnetized by using an excitation magnetic field. Meanwhile, a magneto optical (MO) sensor based on the principle of Faraday magneto effect was used to acquire the MO images of weldments with welded defects. Then, a defect edge extraction algorithm with a better anti-noise property was investigated based on wavelet modulus maxima multi-scale information fusion theory to process MO images suffered from serious noises, low contrast and complex background. Finally, the PCA was taken to preprocess the column grey variables of MO images and 256 feature points of column variable of MO images which could characterize grey variable by 95% were obtained. Furthermore, these feature points were regarded as inputs of a three-layer BP neural network model to classify the welded defects. Experiment results show that the proposed method can be applied to detection of welded defects as mentioned above, and the accuracy of PCA-BP classification model has reached to 90.80%.

Ａ super-resolution algorithm based on TV-L1 decomposition was proposed . In the algorithm, the original-dual algorithm was used to solve the TV-L1 image decomposition model, and the low resolution image was decomposed into the structure and the texture parts. The structure part was processed with a soft decision adaptive interpolation. For the texture part, the Nonsubsampled Contourlet Transform (NSCT) characterized by multi-direction and shift-invariance was used to construct the nonlinear gain function to process the NSCT transform domain coefficients, then the processed transform coefficients were enhanced their textures by the NSCT inverse transform. Finally, the reconstructed high resolution image was obtained by combining the processed the structure and texture parts. Experimental results show that the proposed algorithm in both visual effect and the quantitative evaluation on image quality is better than the traditional interpolation method. For realizing twice super-resolution, its peak signal-to-noise ratio (PSNR) and Structural Similarity (SSIM) average value are increased by 1.316 2-4.591 9 dB and 0.007 1-0.020 6. For realizing three super-resolution, the PSNR and the SSIM are increased by 0.338 7-4.58 0 dB and 0.001 8-0.041 7, respectively. Because of the accurate representation of the different morphological features of the cloud image, the SAI interpolation and NSCT not only reconstruct the smooth component, but also maintain the texture and edge of the infrared nephogram.

To optimize the tracking property of Camshift tracking method under a complex environment, the principle of constant cross ratio of internal feature pixels in tracked objects was used to improve the Camshift tracking method. By analyzing the tracked object model, the coordinate relationship among the internal feature pixels was calculated by using this method, then the internal datum's cross ratio invariant was regarded as the constraint condition of the proposed tracking method to correct the wrong tacking pixel points, and the distance ratio of internal feature pixels between two successive frames in the tracking process was taken as the judgment criteria. This proposed Camshift tracking method was used to test the video information respectively in a standard test video and in an actually shot video. Comparison results show that the distance deviation of the tracked object maintains within 15 pixel and the average handling time of single pixel is within 20 ms under the condition of two kinds of complex environment experiments. It concludes that the improved method has stable tracking property, higher tracking efficiency and good tracking results under the complex environment, and it satisfies the requirement of real-time tracking systems.

To achieve early diagnosis and online real-time monitoring of faults for a bearing, a new type of over constraint three-dimension force and moment sensor was put forward. By adopting six symmetrical distribution load branches which all did not pass their centers, the sensor could simultaneously measure the bearing radial load and axial moment. According to the static equilibrium equation, the mathematical model of measurement was established. Based on sensor measurement model and performance index, the performance of the sensor was analyzed, and the structure parameters were optimized. Then a sensor prototype and its load calibration experiment system were developed. Meanwhile, the load calibration experiment was carried out, and the measuring accuracy of the sensor was obtained.The calibration experiment shows that the radial force measuring accuracy is 2.56%, torque measurement accuracy is 0.92%, type I error is 2.56%, and the maximum of type Ⅱ error is 2.29%.The work lays a foundation for the applications of new constraint planar parallel three dimensional force/torque sensor to the online real-time measurements of bearings on radial loads and axial friction torques.