The relation between the prisms′ orientations and the corresponding pointing positions of an outgoing beam should be figured out when a beam steering mechanism was used to steer the direction of optical beam. Therefore, this paper explored the beam steering mechanism of a rotational double-prism pointing system by applying first-order paraxial approximation method and nonparaxial ray tracing method. Then, it calculated the analytic formulae of the pointing position for the outgoing beam based on the prisms′ rotational angles. The results obtained with the two methods were compared and validated by designed beam steering experiments of rotational double prisms. The results show that the nonparaxial ray tracing method can describe accurately the beam steering mechanism, while the results obtained with the conventional first-order paraxial approximation method has a difference from the experiment value. The larger the beam′s angular deviation is, the more obvious the difference between the solutions with first-order paraxial approximation method and the corresponding experiment values is. When the difference of the prisms′ rotational angles is 90°, the difference between the solutions of azimuth with first-order paraxial approximation method and the corresponding experiment values becomes a maximum one. It suggests that the nonparaxial ray tracing method is suitable for discussing the beam steering mechanism for the rotating double-prism beam steering system with a large angular deviation.

To research the stability of Mg-based multilayers,two groups of multilayers, ［Mg/Co］20 and ［Mg/SiC］20 were coated on a Si(100) substrate by magnetron sputtering method. The two samples were tested by a microscopy, a surface roughness experiment and an X-ray grazing incidence reflectivity test at room temperature and a relative humidity of 80%.The contract experiments on multilayer damage for Mg/Co和Mg/SiC were performed in the same condition. The results show that after being exposed in the atmospheric environment for 4 days, the damaged area and surface roughness of the Mg/SiC multilayer sample are up to 26.34% and 10 nm, respectively, while those of the Mg/Co multilayer sample are 2.78% and 5 nm, respectively. After 6 days, the 1st reflection peak of Mg/SiC sample is completely disappeared, and Mg/Co sample still has a peak of 47.63% reflectivity. The experimental results show that the Mg/Co multilayer sample has a better environmental stability as compared with the Mg/SiC multilayer. The X Photoelectron Spectroscopy (XPS) shows that the productions of the damaged Mg-based multilayers are mainly MgCO3, Mg(OH)2 and modest MgO. Moreover, the content ratio of Mg (OH)2 and MgCO3 in the inner layer is significantly higher than that in the surface layer. Experimental results suggest that the reason for Mg-based multilayer damage is the erosion of H2O(g), so the capping layer of Mg-based multilayer should prevent the H2O(g) penetrating into the mulilayer.

In consideration of the requirements of a large ground-based high resolution imaging telescope for the Wave-front Processor (WFP) of an adaptive optical system in output scales, processing speeds and control bandwidths, an adaptive optical system with thousand elements was explored. The adaptive optical WFP was composed of a master control computer, a wave-front processing host board and expandable wave-front processing sub boards and its output scale could reach the maximum of 1 200 elements. Large-scale logic devices were adopted as main processing chips, and a multithreading parallel pipeline algorithm was used to shorten the wave-front processing delay and promote the controlling bandwidth of the system. Then, an open loop experiment based on 961-element deformable mirror and a closed corrected experiment based on 137-element deformable mirror were performed. The result shows that the wave-front processing delay is 20.96 μs when the maximum sampling rate is 2000 frame/s，which demonstrates that the hardware expending circuit and multithreading parallel pipeline algorithm are feasible and effective for the wave-front processing of the adaptive optical systems.

As space-based cameras have advantages of lower energy consumption, higher accuracy, and easy to be miniaturized when they are used to observe space objects with middle or smaller sizes, this paper explores the orbit determination method and observability calculation method of space objects by space-based cameras. The advantages that the sun synchronous orbit is set as a space-based satellite orbit are analyzed and a space-based satellite orbit is designed by referencing several foreign space-based satellite orbits. Then the visible arc sections of space objects for different orbit types are simulated based on the space-based satellite orbit. According to the orbit measurement accuracy of existing space based optical observation equipment and errors of orbit dynamic model, the different system errors ,random errors and dynamic model errors for the orbit measurements are added. Finally, the orbit determination precisions for space objects in different orbital altitudes are analyzed. Analysis results show that, for determining space target in low earth orbit with 6 of 7 minutes a day / two days of space-based optical measurement orbit data, the orbit determination precision is coincident with that of the United States of America cataloging (Two-line Elements,TLE) when the orbit measurement accuracy is better than 30″ and the dynamic model error is less than 50%. Moreover, for determining space target in earth synchronous orbit with 10 min / day of space-based optical measurement orbit data, the orbit determination precision is in the orbit accuracy range of the United States of America cataloging when the orbit measurement accuracy is better than 10 " and the dynamic model error is less than 50%.

To obtain stable laser outputs, bigger turning ranges and higher transfer efficiencies by a simple and compact resonance cavity, a V-type Optical Parametric Oscillator (OPO) pumped by a 1 064 nm Nd∶YVO4 laser is designed, and broadband wavelength-tunable, continuous-wave (CW) mid-infrared laser sources are obtained . The Nd∶YVO4 laser crystal is pumped by a 808 nm semiconductor laser to generate a 1 064 nm laser as the fundamental frequency light ,and the V-type cavity is used to control laser spots and to change the grating period and temperature of the PPMgLN to obtain the 2 249 to 3 706 nm tunable idler output. With an 808-nm pump power of 10.5 W and a polarized period of 29.98 μm, a maximum idler output power up to 650 mW at 3 466 nm is achieved under the PPMgLN to be set at 411 K, which shows a better monochromaticity and is corresponding to a center wavelength of 3 466 nm and line width of 2.6 nm. Moreover, when 808 nm pump power is 7.5 W, the maximum optical-to-optical conversion efficiency can be up to 7.73% and the corresponding output power is 580 mW.

To detect the terahertz radiation of a low temperature blackbody accurately, the difference between infrared radiation and different terahertz radiations of the blackbody was researched. A low temperature blackbody terahertz radiometer was established with narrowband spectral filtering method. First, the emitted spectral radiances were calculated by Planck′s law in various terahertz wave bands. The results show that the radiances of blackbody in the infrared band are four to ten times than that in the terahertz band from 223 K to 323 K. Then a low-pass filter and several band-pass filters were made up a filter combination with high transmission in various wavelengths. The filter combination was used to filter the infrared radiation and to transmit the terahertz radiation to implement the terahertz spectral radiance measurement. Experimental results reveal the deviations of terahertz narrowband radiations at different bands for the blackbody and indicate that spectral filtering method can realize the detection of terahertz radiation of the blackbody.

To measure the beam profile and power density distribution of a far field target in high energy system performance evaluation, a high energy laser detection method is proposed by combining photoelectric and calorimetric methods. In the method, the total energy of incident laser is measured by an absorber and the spatial and temporal distribution of laser profile measured by a photoelectric detector. The detector is developed, which is consisted of a graphite calorimeter, an InGaAs photoelectric detector array, a temperature and voltage amplifier, an analog to digital converter and a signal processor. The system with an effective sensitive area of 22 cm×22 cm can offer a spatial resolution of 1.1 cm,a temporal resolution of 20 ms,and a low energy measurement uncertainty less than 10%.With the higher temporal resolution and lower energy measurement uncertainty,the system is suitable for high energy and large area near-infrared laser beam measurement.It has been used in field experiments successfully.

A novel X-Y micro-motion mechanism was proposed based on a flexure hinge to meet the demand of the lithographic lens for X-Y adjusting mechanism with a small range and a high precision, then it was applied to the lithographic lens model to testify its performance. Firstly, the working principle of the mechanism was introduced based on the concept of mechanism degree of freedom(DOF) and instant center. Then, the structure of the mechanism was designed by using the flexure hinge instead of tradition hinge and the motion rigidity of mechanism, the ratio of input and output for displacement and its natural frequency and modes were all analyzed. The analysis results show that the rigidity values of mechanism X and Y are 1.99 μm/N and 1.96 μm/N respectively, the ratio of input and output for displacement in X and Y axes are -2.5 and -2.56, respectively, and the principle errors in X and Y axes are 8.22％ and 6.68％, respectively of its useful displacement. Finally, the mechanism was used in the lithographic lens systems to prove its performance, and the wavefront aberrations of the lens system were tested. The experiment results indicate that the wavefront aberrations of the systems before and after the mechanism adjusting compensations are 50.864 nm and 25.933 nm respectively. The X-Y flexural mechanism has good performance of aberration compensation, and it can satisfy the requirements of lithographic lens for high precision X-Y micro adjusting.

When UV-Nanoimprint Lithography(NIL) is used in manufacturing gratings of Distributed Feedback Laser Diodes(DFB LDs), the resist often turns into a high polymer after curing and can not be eliminated completely. To eliminate the residual resist, a multi-mask layer process was demonstrated. In this process, a 50 nm SiO2 hard mask was deposited between the wafer and the UV-curable resist and then traditional nanoimprint lithography based on soft stamp UV-imprinting was executed. Following that, the Inductively Coupled Plasma(ICP) dry etching was used to transfer the pattern on the substrate. Finally, it was rinsed with Buffered Oxide Etchant(BOE)for a few seconds .The effect of etching time on the duty ratio of grating was explored and the grating morphologies processed by traditional method and proposed method were compared. A scanning electron microscope image of rinsed grating shows that the grating with about 240 nm pitch and 82 nm depth offers a clean surface and a good feature. Therefore. The proposed method not only can eliminate the residual resist effectively but also can avoid the morphologic damage.

This paper reported on the microfabrication of alkali metal vapor cells based on the two-step low temperature anodic bonding for the chip-scale integration of atomic clock, atomic magnetometer, atomic gyroscope and other atomic devices. Cell structures were fabricated by Micro-electromechanical System (MEMS) bulk silicon process, and the etched silicon with cells was firstly bonded to Pyrex glass to fabricate preformed chambers by the standard anodic bonding process. Then, nitrogen buffer gas and micro-scale alkali metal (rubidium or cesium) were introduced into the preformed cells. The two-step anodic bonding process was used to seal the cells at a temperature lower than the paraffin flash point (198 ℃). In the first step, bonding voltage was lower than the breakdown voltage of nitrogen buffer gas to pre-seal the cells. In the second step, the bonding was in air atmosphere, and the bonding voltage increased up to 1 200 V to strengthen packaging quality. A high power laser system locally heated the micro-scale alkali metal packets to release alkali metal, and a uniform coating of paraffin was formed on cell walls to prolong the life of the polarized atoms. With proposed method, 95% bonding is achieved by the two-step low temperature anodic bonding, and the alkali rubidium still has a metallic luster after anodic packaging. The achieved minimum volume of double-cells is about 6.5 mm×4.5 mm×2mm. Rubidium absorption spectrum shows that alkali rubidium is effectively encapsulated in the cells. It is feasible to fabricate MEMS alkali metal vapor cells by the two-step low temperature anodic bonding process.

To effectively enhance the radiation bandwidth of 60 GHz patch antennas, a micromachining process for the Low Temperature Co-fired Ceramic (LTCC) substrate was proposed. Specific green tape layers of substrate were micromilled to form perforated structures which were then filled with sacrificial materials. Thereafter, the individual layers were stacked up and sintered to form a three-dimensional (3D) microstructure. The cantilevers, enclosing frame structures and embedded microchannels were fabricated to verify the effectiveness of the process. The electrical properties of the antenna designs were validated by a full-wave analysis, and the effectiveness of the cooling channel was experimentally tested. The experiments show that the proposed process solves problems like the variation of contraction rate in various axes and the collapsing of the embedded cavities. The 3D frame, cantilever and the embedded microfluidic structure are fabricated with a maximum aspect ratio as high as 4∶1, and a total thickness of 1.4 mm (14 layers). The cross section size of the microchannel is as large as 200 μm×200 μm and its maximum length is beyond 2.5 cm. With smooth inner walls, the smooth microfluidic flow may provide a cooling effect over 40 K for the integrated power devices with a heating power density of 2 W/cm2. The simulated radiation pattern shows a doubled increase of radiation bandwidth from 2.7 GHz to 5.3 GHz and has a little gain loss. These results demonstrate that simple and low-cost micromachining may effectively enhance the radiation bandwidth of patch antennas without additional costs, which is beneficial to the design and implementation of large scale and highly integrated transmitting/receiving arrays with active power devices.

The influence of the uncertain disturbance from a variational aircraft attitude angular velocity on the forward image motion compensation of reflector in an aerial camera was researched and a disturbance observer was designed to observe the equivalent disturbance restrained by the corresponding compensation of the controller. The mathematic model for a mirror system was introduced based on the torque disturbance. Then, the external torque disturbance and the difference between nominal model and actual target caused by the variational model parameters were equivalent to the control input. The equivalent compensation was brought in the control to suppress the disturbance. Finally, the propose method was used to design a controller with a disturbance observer for an aerial camera mirror to achieve image motion compensation control. The experimental results show that as compared with advanced PID method, the compensation control algorithm based on the disturbance observer can reduce the forward image motion residuals by about 40%- 60% under the same disturbance. In conclusion, the method improves the compensation precision and the robustness of compensation control for forward image motion of the reflector in the aerial camera.

To monitor the structure deformation of an underground tunnel, a high-resolution wireless inclinometer was developed in this paper,and the algorithm of temperature compensation and digital filter applied to the wireless inclinometer were analyzed. First, based on complex conditions in the underground tunnel, the hardware structure of the wireless inclinometer was presented combined the Micro-electromechanic System( MEMS) with the Wireless Sensor Network(WSN) technology and the software processes of wireless communication and PC interface of the inclinometer were described. Then the effects of different environment parameters on the inclinometer were discussed according to the conditions of underground tunnel such as wide-range temperature changes and frequent vibration. Finally, the temperature compensation and resistance to vibration interference were achieved, and the accuracy of the inclinometer was improved. Experimental results indicate that the precision of the inclinometer is 0.05° in the range from -30°to 30°, which meets the design requirements of the underground tunnel for the monitoring deformation.

In consideration of the effect of consequent elastic strain due to the lattice mismatch on the electronic structures of Quantum Dots( QDs), a six-band K·P model was used to explore the two lowest single-particle hole states in two vertically Coupled InAs/GaAs QDs (CQDs). The elastic strain due to the lattice mismatch between InAs and GaAs was included in the calculations. The theoretical results indicate that uniaxial strain effects play a dominant role in the band offset and they affect the hole states of the coupled dot system. First, it increases the splitting energy between the heavy-hole (HH) and light-hole (LH) levels and reduces the mixing of HH and LH. Simultaneously, the strain in the dot molecule affects the potential distribution of CQDs, inducing more ground states are confined on the bottom dots. Compared to the case without strain effect, the critical distance between QDs is reduced to about 2 nm, by which the hole ground states are anti-bonding-like. Therefore, the strain effects in the CQDs change the potential distribution,weaken the coupling strength between HH and LH and reduce the critical inter-dot distance.

A force control method based on reverse engineering and an impedance model was proposed for the robotic grinding in a kind of rotary shell′s inner surface with dynamic uncertainties. Using quasi-online laser measuring approach, the coarse and precise measuring processes were implemented for inner surface with longitudinal curve data and the 3D model of the rotary shell′s inner-surface was reconstructed. Combining an impedance controller with an intelligent control method, the algorithm of the reference trajectory of fuzzy adjusting was adopted. In virtue of the environmental geometry using laser measuring, the reference trajectory was accounted. According to the environmental change in stiffness, a fuzzy logic controller was used for adjusting the scale factor in sampling time. A robotic open architecture platform with force control was set up for laser measuring and grinding process. The force tracking experiments for inner-surface with dynamics uncertainties were performed. The experimental results show that the mean absolute difference rate of the model is less than 0.024% with laser measuring. The inner wall surface of a solid rocket engine was chosen for grinding experiment, and experimental results indicate that the mean absolute difference rate of force tracking is less than 5% and the difference rate of grinding depth is within 6.5% with setting depth of grinding of 0.200 m. These results prove the validity of the proposed method.

A novel flexible support structure for the 1-m primary mirror of a space camera was introduced. By taking the material selection, diameter-thickness ratio, number and positions of support points, and lightweight forms as design variables and the surface figure accuracy rms of the mirror under the self-weight as objective function, a kind of back opening SiC space mirror with triangle lightweight holes and three-point support on the back was designed optimally. Then, the flexible support structure was designed for the primary mirror. Through sensitivity analysis, the parameters of flexible support structure that effect on rms of mirror were found when its optical axis was on the horizontal state. By using finite element method, the dynamic and static stiffnesses as well as thermal character of the primary mirror subassembly were analyzed. The results indicate that surface accuracy of the mirror has reached rms 5.6 nm and 2.7 nm under gravity perpendicular to optical axis and a uniform temperature rise of 4 ℃, respectively, and the fundamental frequency of the primary mirror subassembly is 192 Hz. Finally, dynamics test was performed in the laboratory, experimental results indicate that the first-order natural frequency is 197 Hz and the maximum stress is 181 MPa, which verifies the accuracy of FEA. Obtained results satisfy the requirements of space application.

In order to investigate the characteristics of the package and fiber coupling of a Superconducting Nanowire Single-photon Detector (SNSPD), the SNSPD was successfully built up in our laboratory. Experiments show that the quantum efficiencies of the detector under different light wavelengths are 6%@1310nm and 3%@1550nm when the dark count rate is 100 Hz. Then, as the distance(gap) between SNSPD and optical fiber would be changed due to the thermal stress during cooling, and would cause a misalignment, two kinds of fiber coupling methods to modulate the gap at room temperature were proposed. Finally, by altering the wavelength of the input light, the exact values of the gap at different temperatures were measured and then the influence of temperature on the gap were figured out by an experiment. The experimental results indicate that decreases of the gap for the two packages are 4.1 μm and 17 μm when the temperature dereases 270 K. Based on the analysis of package material and structure, the gaps at both room and low temperature were calculated theoretically. The result fits well with that of the experiments and it may offer some references to the design of new package and fiber coupling in the future.

When a white light interferometer is applied to 3D surface microcosmic topographic measurement, the measuring accuracy is effected by the hysteresis and creeping phenomenon generated by the piezoelectric actuator seriously. Therefore, this paper proposes a method to improve the displacement accuracy of the reference mirror along the optical axis direction. The piezoelectric actuator is given, and its displacement detecting circuit, PID closed loop control algorithms, and creep compensation control are studied. First, displacement detecting circuit is established by a position sensitive device and an optical lever, by which the piezoelectric ceramic micro-displacement can be fed back to control the system, then the PID closed-loop control algorithm is established. Furthermore, the creeping characteristics of piezoelectric ceramic is discussed during the measurement. In order to eliminate the creeping phenomenon and improve measurement accuracy, the “voltage creep” compensation model is proposed. Finally, an integer control system based on PID closed-loop control and creep compensation control is established. The micro-displacement of the piezoelectric actuator is measured by a high-precision XL-80 laser interferometer under the two cases of PID closed-loop control and integer control. Experimental results indicate that the displacement error for the former is 0.007 μm, and that for the latter is 0.005 μm,respectively. This method reduces the influence of hysteresis and creeping on measurement results, and meets the requirements of three-dimensioned shape measurement for high accuracy.

For the special requirements of Thirty Meter Telescope( TMT) from USA, the Rotator assembly of M3S for the TMT was designed，and a design method was put forward for a rotation bearing when its load was varying. By analysis of the motion and force-giving modes of the system and comparison with large photoelectric telescope,a three-row roller bearing scheme was chosen and the model of bearing was established. The zenith angle was defined as a variable, and the most serious working condition was confirmed then the telescope position was determined at this moment. The bearing deformation and stress were calculated by the numerical calculation and Finite Element Method(FEM) when the telescope was stopped at this position. Obtained results from the two methods are in good agreement, which demonstrates the accuracy of the model. Experiments indicate that the maximum axial deformation on the single roller will not exceed 0.015 mm in x, y, z directions and the angular deformation is less than 1.7×10-5 rad when the azimuth varies in 0°-65°. The result shows a enough margin for design requirements.

A nano-antenna with two resonant frequencies and wider resonant areas was constructed. On the basis of the finite integral method , the resonant properties of the surface plasmon optical nano-antenna constructed by Au were calculated and the resonant frequencies and resonant fields in resonant areas were mainly simulated. The experiments show that there are two resonant areas in different resonant frequencies, which are 270 THz at the middle gap and 390 THz at the side gap. Their resonant electric fields are up to 700 V/m, which is about 18 times higher than that of the common dipole antenna when the excitation field is 1 V/m. The resonance field at the first resonant area is confined at the central part from 10 nm to 25 nm along the Z-axis direction, the resonant frequency is almost not changed and the magnitude is greater. The structure with a glass substrate of refraction index of 1.5 is also considered, the resonant field is up to 800 V/m, whereas the resonant center frequencies are almost not changed. The proposed structure has potential applications to high-quality optical antennas, solar cells, and biosensors.

A linear piezoelectric stack actuator used for the focus adjustment system of an interference microscope was proposed and a micropositioner was also developed. The structure of the actuator was designed based on the principle of triangle displacement amplification. The modeling of the steel frame structure was realized by parameter design language APDL in the ANSYS, and the parameters of the structure were optimized by the optimization algorithm of Differential Evolution (DE) in Optimus. A experimental prototype for the actuator was produced, and laser interferometric experiment shows that the actuator′s amplification factor reaches 7 when the drive voltage is between 40 V and 100 V.Finally, the piezoelectric stack actuator was mounted on the micropositioner to be a driver for an interferometer. Experiments show that the step resolution of the micropositioner with flexure hinges has reached 23 nm under the system voltage of 24~40 V and an increment voltage of 0.8 V. These data meet the requirement of interferometric fringe of interference microscope for linear displacement resolution.

A fabrication method combining anisotropic wet etching with isotropic wet etching process is proposed to obtain silicon-based three-dimensional curved rotary profile. In the isotropic etching process, the corrosion rate increases exponentially with the concentration of the etching solution in the vicinity of the silicon surface. The little fluctuation of etching solution concentration varies significantly due to the velocity of the etching liquid flow. On this principle, the surface peak and the bottom of octahedral structure obtained by anisotropic etching are polished by the flow difference existing in the condition of the stirring until one smooth three-dimensional surface occurs. By using the anisotropic wet etching to control the depth of the structure and the isotropic wet etching process to polish the curved surface of the structure, a silicon-based three-dimensional curved rotary profile with the height of 100-200 μm is fabricated based on a circle mask pattern with the diameter of 600-1 000 μm. The method proposed is simple, effective and can be used in fabrication of various three-dimensional silicon molds.

Coarse-grained (CG) models based on molecular dynamic were developed to analyze the flowing process of polymer melt in nano-sized channels on a mesoscale. Firstly, atomistic models of amorphous isotactic Polymethyl Methacrylate(PMMA) were built by Materials Studio， and initial CG models of different mapping centers were then developed based on the models mentioned above. After the structure optimization and kinetic analysis of the atomistic models, the statistic law of potential energy of the system was obtained and the initial force field forms were calculated by Gaussian fitting function and Boltzmann inversion method. Then, the formula of force field was iterated and modified according to the relative strength and the relation of bond, angle and nonbonded potentials and an optimized CG model was obtained successively. Finally, the static properties of the CG model, such as mean square end-to-end distance and mean square radius of gyration, were compared to those of atomistic simulation, and obtained relative deviations are 0.68% and 6.6%, respectively. The results demonstrate that the mapping center has impact on the models and the optimized CG model reproduces the atomistic model well. It can be used to analyze and explain the flow and mass transfer behaviors in the nano-injection molding process.

According to the applications of Diamond-Like Carbon(DLC) films to precision mechanical parts, a method to deposit a DLC film by DC-CVD at room temperature was explored to improve the bonding strength between film and metal substrates. The a-Si∶H intermediate material was intercalated between a substrate and a DLC film, and friction properties and bonding strength of the a-Si∶H∶DLC films deposited on different metal substrates were investigated and evaluated, and then their friction coefficients, fatigue failure life and the wear were determined by Ball-on-Disk. Experimental results show that the bonding strength at the interface is greatly improved by intercalating a-Si∶H intermediate layer, the DLC film is completely worn out without delaminating. Moreover, the maximum thickness of film deposited by the equipment developed by ourselves is less than 3.3 μm, the failure lifetime within the thickness of 1 μm is up to 0.7 million cycles as applying a load of 2.94 N (point load), and the friction coefficients between DLC film and SiC, Si3N4, SUS304, SUJ2 are about 0.1-0.15. In conclusion, the bonding strength and friction properties of the film can satisfy the requirements of precision mechanical parts.

As the efficient clamping of a capsule endoscope in an intestine plays a major role for its stopping and movement in the intestine, this paper investigated and designed a kind of clamping mechanism for the capsule endoscope. Firstly, the influence factors of clamping force were discussed on the analysis of the friction and stress force of the intestine, then a clamping mechanism of Archimedean spiral legs was designed in consideration of the security of the intestine. A test platform was built to measure the clamping force of mechanism by comparing the different diameters, widths, textures and shapes. On the basis of the analysis of test result, an equation of clamping force was established. Finally, the safe control of clamping mechanism was implemented by a current feedback and the safety and reliability of Archimedean spiral legs were proved. Experimental results indicate that the optimized clamping mechanism would be 1.486 N. It can satisfy the anchoring requirements of expanding intestine and assuring the safety of colon.

To enlarge the dynamic measurement range of a Micromachined Tunneling Accelerator(MTA) and to improve its performance by reducing the influence of main noise operated in a closed-loop mode，a Linear Quadratic Gaussian (LQG) optimal controller was designed for our MTA to maintain a constant tunneling gap. The linear state space equation for the MTA was deduced, and an Kalman filter and an optimized sate feedback controller were designed. Finally, a simulation system was constructed by combining the Kalman filter and the optimized sate feedback controller in series, and simulation tests were performed. Obtained results show that the bandwidth of the MTA has been increased from 2×103 rad/s to 3×106 rad/s by the optimal control system. Moreover, the fluctuation of the static tunneling current is decreased from 1-2.95 nA to 0.73-1.14 nA from a static test and the distance from the proof mass to the tunneling electrode is effectively regulated to its nominal value of 1 nm under the dynamic square-wave accelerator.

With the aim to attenuate the effect of wind load disturbance on the tracking precision and the life-span of a large deep space observatory antenna, this paper proposed a wind disturbance rejection servo system. As disturbance observer can improve the system performance, the mechanism of electrical motor was utilized to simplify the design process. The feedback channels of current and speed control as well as load impact were regarded as parts of the total disturbance, and the lags in the feed-forward channels were approximated by their steady gains respectively. Therefore, the required order of the extended state observer, which was employed to estimate the total disturbance, including the wind load torque and other uncertain mechanical dynamics, could be substantially reduced. Then, the total disturbance was compensated by the observer. Furthermore, the limit cycle was eliminated in the presence of friction according to the describing function method. Finally, mathematical simulations and experiments were carried out. In the experiment, the overshoot is reduced by 34% and the capacity of gust rejection is increased by 60% ,respectively, as compared with that of traditional equipment, while the tracking precision is also raised significantly. The objective of rejecting the wind gust disturbance for the large deep space observatory antenna system can be achieved by using the proposed method.

As conventional super-resolution algorithms can not implement the motion estimation and reconstruction for an image with local motion in practical engineering applications, this paper proposed a super-resolution reconstruction algorithm based on NonLocal Means (NLM). First, the NLM filter, one of the successful denoising filters in recent years, was introduced briefly. Then, the details concerning its application to super-resolution were analyzed by creating a super-resolution cost function. By considering the practical situations and the need of the engineering facet, a scheme to simplify the procedure in the NLM super-resolution algorithm was proposed. The experiment results show that the simplified algorithm can not only effectively implement super-resolution reconstruction to get a clear and detailed image without explicit motion estimation, but also can obtain a reconstructed speed higher 30% than that of conventional algorithms. It can satisfy the practical needs of engineering set-tings and is expected to reconstruct the high resolution image with complex motion.

This paper presented a multi-scale light spot center location method to extract the center location for irregular light spots in an image fast and accurately. Firstly, the region of the light spot was segmented by morphology operation and thresholding to determine the size of the image with spots. Then, the Hessian matrix was computed in the multi-scale image space in the light spot region. The best scale was determined by a determination coefficient from the eigenvalue of Hessian matrix, and the pixel level center location was computed. Finally, the image intensity function around the spot center pixel location was approximated by second order Taylor expansion and the sub-pixel center location was computed by finding the maxima of the approximated intensity function. Both the synthetic and real experiments verify that the proposed method has higher location accuracy and stronger robust. In a real experiment, the error of the light spot center location is less than 0.1 pixel. The method proposed has been put into the practice of video measuring systems.

Because natural image filter response probability model is often a non-Gaussian form(sparse), it leads to the optimization problem of image restoration to be a non-convex and the optimal estimation solution can not be obtained by traditional maximum a posterior estimation. Therefore, this paper proposes a image restoration algorithm based on adaptive weight matrix to solve the problem. With image restoration, a prior model for the natural image is used to restrain the ring effect effectively and the conjugate gradient algorithm based on adaptive weight matrix is used to solve the problem of the non-convex optimization function due to the sparse prior. The weight matrix updates according to the last iteration result and is able to correct the error of the local image derivative estimation in the last iteration process. Experiments show that Peak Signal to Noise Ratio( PSNR)gotten by proposed algorithm is 36.131 6, better than that from other algorithms. Finally, the panoramic image is restored by proposed method and the good results are also obtained, which demonstrates that the algorithm proposed is practical and effective.

By optimizing the feature vectors and Gaussian Mixture Models(GMMs), a hybrid compensation method in model and feature domains is proposed. With the method, the speaker recognition features effected by the noise and the declined performance of GMM with reducing length of the training data under different unexpected noise environments are improved. By emulating human auditory, Gammatone Filter Cepstral Coefficients(GFCC) is given out based on Gammatone Filter bank models. As the GFCC only reflects the static properties, the Gammatone Filter Shifted Delta Cepstral Coefficients(GFSDCC) is extracted based on Shifted Delta Cepstral. Then, the adaptive process for each GMM model with sufficient training data is transformed to the shift factor based on factor analysis. Furthermore, when the training data are insufficient, the coordinate of the shift factor is learned from the GMM mixtures of insensitive to the training data and then it is adapted to compensate other GMM mixtures. The experiment result shows that the recognition rate of the method proposed is 98.46% . The conclusion is that the performance of speaker recognition system is improved under several kinds of noise environments.

According to the different sensitivities of human eyes for different color channels of color images and the effect of tolerable perception range of human eyes on color image perception，a color image objective quality assessment method based on visual threshold and channel integration is proposed. Visual threshold characteristics of human eyes are used to determine whether the distortion of a stereoscopic image can be perceived. If the degree of distortion is within the tolerable range of human eyes, the distortion is ignored. Singular values of difference maps between original and distorted images with respect to the left and right views are compared with singular values of the visual threshold map of original images, so as to assess the quality of the left and right views, respectively. For original and distorted stereoscopic images, the difference between their left view and the right view are calculated, and the difference map of the above two differences is further calculated. The singular values of the difference map are then compared with singular value of binocular just noticeable difference to assess the quality of stereo perception. For different types of distortion, the weights for fusing the assessments of the left and right views, and the weights for fusing the assessments of the left-right views and stereo perception are different. The experimental results on 312 stereoscopic images distorted with Gaussian blur, Gaussian white noise, JPEG, JP2K and H.264 show that the proposed objective model can achieve more than 0.94 Pearson Linear Correlation Coefficient(CC) and general Spearman Rank Order Correlation Coefficient(SROCC),respectively, and the overall Rooted Mean Square Error(RMSE) is less than 5.9, which means that the assessment score obtained by the proposed model is well consistent with that obtained by human subjective perception.

A detecting method for motor rotor position was proposed based on image measurement technique. Firstly, the image of motor rotor was taken by a high-speed area CCD ceaselessly when the motor was rotating; then every two collected adjacent images were converted from a Descartes coordinate to a polar coordinate; finally, these images in the polar coordinate were calculated by phase-correlation algorithm, and the rotation angle was obtained according to the position of the phase-correlation peak. As the texture information of calculated image was related to the accuracy of phase-correlation, the calculated image was reconstructed to obtain an image to assure the right calculated result for implementing exact detection. Meanwhile, detection efficiency was required to increase, so the adaptive method was used in polar transformation, namely, only part of the pixels in the image was sampled according to the need of measurement precision. Experimental results show that the measurement accuracy of the proposed method is 100% and this measurement can be achieved in the environment with some different illumination intensities. Moreover, the calculating time can be reduced by over 50% as compared with that using polar transformation directly. The proposed method provides a reliable way for the detection of motor rotors.

On the basis of laser alignment and image detection technologies, an image based online surface settlement monitoring system was established to achieve the online surface settlement monitoring of ballastless track. Firstly, the operational principle of the image based settlement monitoring method was introduced and the components and working model of the online surface settlement monitoring system were described. Then, the image features of laser spot on the target surface for settlement monitoring were analyzed and the background difference method was used to improve the environmental adaptability of the monitoring system. Furthermore, the images of laser spot were preprocessed by the algorithm based on the multi-scale and generalized morphological filter with variant structuring elements. Finally, the center position of laser spot was accurately determined by a gray distribution curve fitting algorithm based on the center of gravity. The experimental results show that the combined uncertainty tested in a settlement laboratory is up to 0.198 mm and the maximum cumulate error under the field test for 10 months is less than 1 mm. The system has met the requirements of online surface settlement monitoring of ballastless track for high stabilization, reliability, precision, and capacity of resisting disturbance.

Acquiring， tracking and pointing(ATP) technique in a 100 km quantum entanglement distribution experiment was introduced in detail. By taking a 700 mm telescope at Alice receiving terminal as an example, the technological specification, light path layout, and tracking accuracy of the ATP system were analyzed. In order to reduce the angle-of-arrival fluctuations of quantum information transmission beams and beacon beams caused by air turbulence, a cascade acquisition and tracking system with coarse tracking, fine tracking and a ultra-fine loop was designed and a dual fast-steering mirror tracking algorithm was proposed. On the basis of a higher frame frequency CMOS detector and a piezoelectric fast -steering mirror, the ultra-fine tracking circuit was developed. Experiments show that these methods solve the contradiction between tracking dynamic range and tracking accuracy, promote the performance of the detector and improve band width and tracking accuracy. The system was used in a ground 100 km quantum entanglement distribution experiment and the results indicate that the tracking error of the system is 4 μrad for a 70 Hz bandwidth.

To measure accurately the attitude of a spatial object that was fast-changing in a suspension state, an attitude measurement method was proposed based on three linear CCD cameras for measuring multiple point cooperation targets. By proposed method, the nonlinear systemic errors and more calibration parameters caused by more overconstraints for camera positions were overcome in the traditional linear CCD attitude measurement. Three 1D cameras composed of linear CCDs and cylindrical lenses were used to measure simultaneously the multiple point cooperation targets on the measured object. Aiming at the restriction of measuring principle on the attitude angle, the simulated calculation method was used to calculate the attitude angle range and the BP neural network was taken to calibrate the CCD cameras and give the spatial 3D coordinates of point cooperation targets. Furthermore, an attitude calculation model based on Rodrigues parameters was established to solve the attitude angles of measured objects. Experimental results indicate that the measurement accuracy of spatial point position and the calculating precision of spatial attitude angle in this system are higher than those of traditional methods, which verifies that this attitude measurement method is feasible and available to measure the attitude.