Chinese Version Light学术出版中心
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Issue 5 ， 2008
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Optical Design of a HDE Infrared Dual-band Step-zoom System
Abstract：A dual-band step-zoom infrared optical system comprising only four lenses is designed by virtue of the special properties of harmonic diffractive element and the zoom theory. The result shows that the system has a cold shield efficiency of 100%, the MTF value is over 0.7 at 18lp/mm for the waveband of 3.7μm～4.3μm and the value is over 0.5 at 18lp/mm for the waveband of 8.7μm～11μm. The optical performance approximates the diffraction limit.Keywords：optical design;Infrared;Harmonic diffraction;dual-band;Zoom- 47
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Published：2020-08-12 -
The application of ray tracing method in birefringent filter error analysis
Abstract：Objective: For solar magnetic field telescope with birefringent filter system, the quality of filter directly affects the line shape, and then the measurement of solar magnetic field. Method: According to the property of uniaxial crystal, the ray tracing method can be used to study the transmission law of ray in the filter system. With this method the ray trace, phase and vibration can be expressed by incident angle, azimuth and crystal parameters. Combining with the polarization interference theory, the effect of different error sources on the line shape can be analyzed by computer program. This method provides a reliable basis for the development of filter. Result: The maximum relative error is 0.7%, comparing with Evans equation, which demonstrates the exactitude of method in this paper.Keywords：polarization optics;line shape;ray tracing method;birefringent filter- 35
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Published：2020-08-12 -
Calculation of Light-induced Forces and Torques on a Complex Microrotor by the FDTD Method
Abstract：The microrotor is an important part in the MEMS. There are many advantages of using light to drive micro-rotors, such as its merits of no mechanical contact, no wire needed and small friction. So it is important to find an effective way to design and evaluate the torque on microrotor. With the development of computer, using the wave optics model to calculate the complex rotors’ optical torques has come true. In this paper, a modularized Matlab program was built to analyze the force-field produced by the optical trapping. The finite-differential time-domain method (FDTD) is attempted to analyze the forces and torques on our designed micro-rotors. The electric and magnetic intensity distribution of the scattered light on the surface of the rotor are calculated. Maxwell’s stress tensor is then employed to calculate the force over the rotor surfaces, enabling the determination of the rotor torque about the axis of rotation. The result is also compared with the experiment.- 49
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Published：2020-08-12 -
Detection limit of glucose concentration in noninvasive measurement of glucose with near-infrared spectroscopy
Abstract：Many good experimental results in noninvasive measurement of glucose have been achieved. However, lack of theoretical support counteracts their extensive acceptance. After analyzing the two kinds of effect on optical properties and further influence on light propagation induced by the variation of glucose concentration, the relationship between detection limitation of glucose concentration and source-detector separation and signal-to-noise ratio of measuring system was derived. Referring to skin’s layered model, signal-to-noise ratio was modified accordingly. Monte Carlo simulations performed in a skin-layered model show that the percent of effective photons from dermis layer can be larger than 50% by selecting optimal source-detector separation, and that the requirement of FDA for noninvasive glucose sensing could be satisfied if the instrument SNR of 10000 is supposed.Keywords：Detection limit of concentration;Noninvasive Glucose sensing;Near-infrared spectroscopy- 51
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Published：2020-08-12 -
Notch Filter Design Based on Two-Frequency Bode Diagram for Rotor’s Elastic Vibration Depression of Magnetically Suspended Control Moment Gyroscope
Abstract：In control moment gyroscope (CMG) based on magnetically suspended rotor, owing to wide controller bandwidth required by nutation stability at high rotational speed, bending mode between disk and axis of rotor with I-shaped configuration becomes unstable and turns into self-exciting vibration within the range of rotor speed. This elastic vibration can be depressed through adopting notch filter (NF) in original controller of active magnetic bearing (AMB), but NF design is still an issue since high-speed flat rotor features strong gyroscopic effect and coupling radial motions. An illustrative and robust method based on two-frequency Bode diagram to design NF parameters. By introducing two-frequency Bode diagram, stability of elastic modes are analyzed, correction angle requirements of bending mode at various rotor speeds are summarized, and NF parameters including grade, center frequency and pole damping are designed optimally to minimize influence to nutation stability. Employing the optimized notch filter, elastic vibration amplitude of statically suspended rotor of magnetically suspended CMG was attenuated significantly comparing to original and the rotor is robustly stabilized within entire speed range up to 20000r/min.Keywords：control moment gyroscope;magnetic bearing;Elastic mode;Self-exciting vibration;notch filter;Two-frequency Bode diagram- 45
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Published：2020-08-12 -
Multi-Object Optimal Design of Harmonic drive Based on Precision and Load Capacity
Abstract：this paper proposes a method of Multi - object Optimal Design to balance and meet the various performance requirements for Harmonic Drive in different systems , such as requirement for harmonic drive precision, load capacity or Flexspline fatigue strength in practical engineering. The method sets up multi-object optimal model that takes Meshing backlash，depth in engaging and flexspine fatigue stress as the objective function , at the same time , it changes the value scope of the relative requirements into weight of the linear weighting method in order to make sure that the harmonic drive can not only obtain the optimal transmission performance but also get the better reliability.- 29
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Published：2020-08-12 -
A new method of information-sharing in micro-platform integrated navigation system
Abstract：Abstract: On the basis of analyzing the former methods of information sharing, this paper proposed a new information sharing method based on micro-platform integrated navigation system. A formula of fallibility probability is constructed using the threshold value. The information factor for each local filter is adjusted according to the fallibility probability in its own corresponding subsystem. Meanwhile, the method of adjusting the threshold value on line can reduce the probability of the false alarm and missing alarm in the FDI (Failure Diagnosis and Isolation) process. The simulation experiment shows that this method can effectively reduce the computation load and improve the precision of integrated navigation system.- 28
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Published：2020-08-12 -
Study on mechanical characteristics of aerostatic bearing with finite volume method
Abstract：Aerostatic lubricating is the key technology in the field of precision engineering. The mechanical characteristics of air film, such as pressure distributing, bearing capacity and stiffness is the main factor that determine the stability of air-bearing position. Simplified Reynolds equation is widely employed in aerostatic bearing design, which leads large static error. This paper does research work on mechanical characteristics of aerostatic bearing such as pressure distributing principle, bearing capacity. Going on the premise that jetting air from orifice has the attribute of air impingement jet, the paper introduces finite volume method of computational fluid dynamics (CFD), applies control equation set k-ε model closed of isothermal air for mechanical characteristics numerical analysis of air film and unveils the pressure distributing principle of different thickness air film on aerostatic bearing working plane. The numerical analysis shows that the pressure distributing principle of air film from orifice to edge of air-bearing along the working plane is not degression mentioned by simplified Reynolds equation, but fluctuation that the air flow pressure sharply drops under the atmospheric pressure nearby orifices, then gradually increases above the atmospheric pressure and reverses finally. Based on the analysis of air film thickness and aerostatic -bearing bearing capacity, this paper points out that elastic self-excited vibration caused by gas-solid coupled between air film and aerostatic bearing is the main block of aerostatic bearing’s application in nano-positioning.Keywords：finite volume method;Mechanical characteristics of air-film;Aerostatic bearing;Gas-solid coupled;Pressure distributing- 37
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Published：2020-08-12 -
The Novel method of Face Hallucination
Abstract：This paper focuses on study of super-resolution image of face(Face Hallucination). A novel face hallucination algorithm is proposed in this paper based on multi-resolution pyramid structure. Different from Baker method (reference [1]), We add Kirsch operator to get high-frequency feature of image. Kirsch feature combined with the first and second order gray feature can extract more image information, make the matching process more accurate. In addition, we introduce one of the manifold learning methods, locally linear embedding (LLE) for matching process, to make priori model more accurate, more comprehensive, and having more higher frequency information. Experimental results show that this model predicted a priori be more accurate, it will make the recovery of facial images with better visual effect.Keywords：Learning-based super-resolution;Face hallucination;Kirsch;manifold learning;Locally linear embedding (LLE)- 31
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Published：2020-08-12 -
X-ray Polarization Spectroscopy in Laser-produced Plasmas
Abstract：To diagnose the presence of electron beams in high-temperature plasmas, polarization spectroscopy of x-ray lines is a useful diagnostic method to measure directly the presence of hot electron velocity distribution function inside a strong intense laser fusion produced plasmas. A novel polaried spectroscopy is designed and manufactured based on spatial resolution in laser-product plasmas experiments. This measurement relies on the sensitivity of two crystal spectrometers to the linear polarization of x-ray lines which depends on the value of the Bragg angle. The differential transmission spectrum representing the difference between the values of transmission for linearly polarized radiation with the orthogonal polarizations that are parallel and perpendicular to the optical axis is obtained with crystals at two different Bragg angles. One of dispersive elements is PET flat crystal set parallel channel, and another is Mica spherically bent crystal installed perpendicular channel, whose radius is 380 mm.The image plate ,the effective area of 30×80mm, is employed to record the spatial-resolved spectrum of polarization spectroscopy of x-ray lines. The designed long optical path of the X-ray spectrometer beam is about 980mm from the source to the crystal and the detector. The first experiment was carried out at the 2×10J laser facility of Research Center of Laser Fusion, China Academy of Engineering Physics (CAEP); the X-ray spectrum emitted from the aluminum plasmas was recorded by the image plate. These experimental results show that x-ray polarization spectroscopy is a good tool for diagnosing high-density plasmas created by lasers and that this diagnostic technique could also be applied to other areas of high-temperature plasma research.Keywords：Crystal spectrometer;spectral measurement;X-ray diagnosis;laser-produced plasma- 34
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Published：2020-08-12 -
Micro-structure measurement of phase object by digital microholography based on magnified hologram
Abstract：A digital micro-holographic optical system based on magnified hologram is designed. Compared with the typical pre-magnification system, the proposed system directly eliminates the main phase error introduced by spherical wave before record. In the post-magnification system, the object beam interferes with the parallel reference beam to generate hologram. A microscope is used to magnify the hologram and then recorded by a CCD camera. This method intends to be more useful to the post numerical reconstruc-tion and real-time operation because of no quadratic phase aberration. The system is studied by the experiments with the phase grating (30 lines/mm, about 0.3 µm depth). Besides, Fresnel approximation and convolution algorithm are respectively used to reconstruct amplitude and phase information of the micro sample. Phase depth is about 0.27 µm. The results show that the present system is greatly helpful to restrain the quadratic phase error.Keywords：digital holography;microholography;hologram magnification;phase object- 34
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Published：2020-08-12 -
Effect of optical package structure of LED to intensity distribution
Abstract：In order to realize the main factors affecting intensity distribution of light emitting diode, optical model of the traditional light emitting diode was constructed, which was based on the luminescence principle and structure of the traditional light emitting diode. Intensity distribution plot of the light emitting diode was obtained, and comparison was carried out between data measured by the manufactory and the results got from this research. By changing the field angle of the reflecting cup successively, the distance from the top of the light cup to the bottom of the light emitting diode, the refractive index of Araldite and the dimension of the optical lens, it appeared that light emitting diode owned different intensity distributions, and four groups of intensity distribution plots were got. Experiental results indicate that with the field angle of the reflecting cup being enhanced, the depth of framework thrust into the light emitting diode being increased, the refraction coefficient of Araldite being enhanced and the dimension of optical lens being increasing, the intensity distribution changes abiding by some laws, and these laws could be used to guide the production of light emitting diode.Keywords：light emitting diode;Intensity distribution;Optical model- 35
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Published：2020-08-12 -
Compact modeling method for the electrostatically actuated silicon diaphragm
Abstract：The compact modeling (or macromodeling) method for the MEMS devices is the key issues in MEMS system design and system level simulations. For constructing the compact modeling of the nonlinear silicon diaphragm actuated by a distributed electrostatic force, a nonlinear function fitting scheme is used after several finite element analysis running, where the energy date are calculated for constructing an analytical model of kinetic energy, strain energy and electrostatic co-energy of the system. Then all theses energy function is represented in the term of general mode coordinates and subjected into the Lagrange Equation to deduce the motion equations of the silicon diaphragm. Thus the macromodel was obtained. After that the macromodel was used to simulate the device’s quasi-static and dynamic characteristics. The simulation results were compared with the results calculated by finite element method. All results show that the compact model can capture the quasi-state and dynamic behaviors of the electrostatically actuated silicon diaphragm quite well. This compact modeling method can consider the effect of residual stress and geometry nonlinear and has a low computational cost.Keywords：Compact Model;Mode Analysis Method;Electrostatically Actuated;MEMS- 51
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Published：2020-08-12 -
Research on the temperature precise control in the hot embossing device
Abstract：Thermoelectric cooler was used as the main component of temperature controlling in hot embossing device to acquire high temperature control precision. The control model of thermoelectric cooler was derived by using small-signal linearization method due to its complex thermoelectric performance. A fuzzy PID controller is designed by combined fuzzy control with conventional PID control. Fuzzy reasoning rule of PID parameters is designed according to nonlinear and uncertainty of the hot embossing temperature control system. The performance of temperature control system was tested in the followed experiments. The stepped response tests show that the controller has satisfying dynamic and static performance. The temperature control precision can reach 0.2°C and temperature increasing/decreasing speed is greater than 1°C /s. It can satisfy the system requirements of the precise control of temperature in hot embossing device.Keywords：Thermoelectric cooler;Fuzzy-PID;Hot embossing- 52
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Published：2020-08-12 -
Study on Dynamic Characteristic of a Novel 2-DOF Positioning Mechanism
Abstract：With the quickly development of the IC industry, the positioning table used in the encapsulation installment must possess the characteristics of high and high velocity and high accelerate. It is necessary to study a novel high accelerate and high precision positioning mechanism. Orient to this requirement, a novel precision positioning mechanism is presented. It consists two parallelograms chains, and is drove directly by linear voice motors. Firstly, Largrange equations are used to build the dynamic model of the mechanism. Secondly, based on the singularity value theory, the expressions of velocity extremum and acceleration extremum are obtained. Then the velocity characteritics, and the acceleration ability subject to the limitation of the joint force are analyzed. The analyse results illustrate that the positioning table can get the maximum velocity 0.8m/s at the worst case, the maximum acceleration 12g at the worst case 14g at the best case. Experiments validate that the presented positioning stage can get above performance index and possess the high accelerate characteristics.Keywords：positioning mechanism;Dynamic characteristic;High accelerate- 28
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Published：2020-08-12 -
On modeling of dynamic nonlinear piezo-actuated electromechanical coupling dynamic system and wideband high precision displacement control
Abstract：Abstract: The modeling and displacement tracking control of piezoceramic actuator with complex nonlinear hysteresis behaviour is studied. First, a novel PECLP model is proposed by using the state space function. In this model, the intrinsic dynamic nonlinearity is combined into the piezoceramic stack’s hysperesis for the first time, and the dynamics of elastic and motive components within actuator are considered simultaneously. Then, the input-output linearization theory of differential geometry is utilized to deduce a simplified subsystem provided with linear normal form. By adopting this subsystem, a LQ based nonlinear displacement tracking control system is developed for piezoceramic actuator. At last, some computer simulations are conducted. In contrast with conventional control system, the simulation results show that the developed nonlinear displacement tracking control system exhibits the better tracking precision without static error, and global optimization of system dynamic capability. Furthermore, the frequency bandwidth is expended by one order of magnitude approximately from 638Hz to 5217Hz at -3dB. A satisfied high-speed frequency response characteristic can be achieved.Keywords：Key words: Piezo-actuated;Electromechanical coupling;Dynamic nonlinear hysteresis;Input-output linearization;Displacement tracking control- 32
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Published：2020-08-12 -
Study on vector impedance analysis model of giant magnetostrictive mirco-displacement actuator
Abstract：When Giant magnetostrictive micro-displacement actuator(GMA) was implemented in the precision or super precision finishing occasion, The system was affected by the external load , The dynamics effect lead to the eddy current in the components and the output displacement of system exist hysterisis. Employing the linear piezomagnetism equation, mechanical electrical transformation equation and impedance analysis method to set up the vector impedance model of the system. The model divides the system vector impedance into two sections, mechanical admittance and electrical impedance. Considering the external load influence and define the coefficient of pizeomagnetism as a constant complex variable to simulate the displacement hystersis; in the solved the magnetization in the magnetostrictive material added eddy current term to simulated the system nonlinear characteristics. the sum of two sections were the system vector impedance. As indicated in the comparison between experimental and model data. , the measured vector impedance and the model data error was about 7 percent in magnitude and 7.7 percent in phase. the results show us the model can be simulated the system impedance characteristics under the precision occasion ,and it can guide the design, control and the performance optimize of the GMA system.Keywords：Giant magnetostrictive mircro-displacement actuator;Hysterisis;eddy current;Vector impedance- 79
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Published：2020-08-12 -
Positioning error compensation for a parallel robot based on BP neural networks
Abstract：In order to reduce mechanism end errors and enhance robot motion accuracy，the main error sources of the parallel robot and the limitations of conventional error compensation are discussed for the 6-DOF precision parallel robot designed. An error compensation method based on back propagation (BP) neural networks of articulatory space, by measuring the end pose, is presented in local workspace of precision positioning. Model of BP Network and data sample of error compensation are established, and the data sample is standardized. By the experiment, the node number of hidden layer is achieved. In order to improvement the generalization performance, the overfitting is prevented in the network training. After error compensation, the positioning error and the orientation error reduce by 80% and 60% respectively. The experimental results show that the error compensation, based on BP neural networks of articulatory space, has an obvious effect, which satisfies the accuracy requirements of the precision parallel robot.Keywords：error compensation;parallel robot;BP neural networks- 40
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Published：2020-08-12 -
Improvement of positioning precision for precise stage with compensation
Abstract：System errors should be removed to improve the precision of a precise positioning stage because of their influence to affection the precision. As a mean of effective and lowly-costing compensation, the reverse compensation could be mainly used to eliminate the errors. According the principle of the reverse compensation, the error curve of a stage is reversed to match negatively the original one that was measured and drawn before, so that the largest proportion of error, which is just the system error, could be separated and removed. The positioning stage described in this paper has a 2-layer structure, in which the lower is macro-stage and the upper is micro-one. The macro-stage is driven by precision ball lead-screw and positioned by optical grating. And the micro-stage is driven by PZT and uses an inductance as sensor. The positioning precision of the macro-stage is measured as 17.4μm before compensation, which is, obviously, too big to conform to the requirements of micro-stage’s moving. The precision is improved to 1.3μm after using the principle described above, then the macro-stage satisfies the need of precision positioning. As the same, the precision of micro-stage is improved from 137.6nm to 22.2nm, which accomplishes nano-scale positioning successfully. The experiment shows that the reverse compensation is effective to eliminate the system errors, and on the other hand, it also shows that the method is not very good at removing the random errors because it is impossible to find the reverse curve to match.Keywords：precise positioning stage;reverse compensation;system errors- 46
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Published：2020-08-12 -
The Influence of Drive on Output Signals of Micro-fluidic Gyroscope
Abstract：Objetive: The output signals, induced by micro-fluidic inertial sensor based on the principle of convection heat transfer, were too weak to be detected easily. Now two methods are applied to drive this kind of gyros and then influence on the character performance. Method : First, the operational principle of these devices were analyzed. A silicon micro-fluidic gyro was comprised of a chamber and along each side of the fluid center axis disposed a thermocouple symmetrically. During zero input angular velocity, the temperature was symmetrical such that both thermocouples sensed the same temperature and therefore provided the same output voltage. While the gyro worked, the Coriolis acceleration，induced by an external angular velocity, caused the deflections of fluid velocity to cool the thermocouples oppositely, then, through Wheatstone bridge circuit the temperature disturbance of thermocouples could be converted to a differential output voltage proportional to the applied angular rate of motion. Secondly, the micro-fluidic inertial sensor might be driven by two methods, DC and AC signals. The AC drive technology included the alternating current driving and the alternating voltage driving. The DC actuated might increase the temperature of chamber, driver resistors and the power similar as the alternating current driving. On the contrary, the alternating voltage drive also increased the temperature of chamber as well as resistors but decreased the power of drive. This might influence the character performance of output signals, such as zero drift. Finally, the methods of corresponding measurement and the block diagram were discussed as well. When DC driving, a DC velocity was induced and amplified directly to extract a DC differential output voltage proportional to the external angular velocityω. On the other hand, if the alternating voltage drive was used, the required signals included in sine wave velocity could be selected out with the use of phase sensitively demodulation (PSD), then passed through low-pass filters, amplified and at last obtained the DC voltage proportional to the external angular velocityω. Result: Experimental results indicate that the zero drift of output signals rise continuously and the linearity is 1.62% by DC driving while 0.113% with the alternating voltage actuated. Conclusion: It is concluded that the micro-fluidic gyroscope is characterized by stable zero drift and better linearity with the drive of alternating voltage.Keywords：Micro-fluidic gyroscope;Drive;measurement- 71
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Published：2020-08-12 -
Mechanical coupling error of silicon microgyroscopes
Abstract：The mechanical coupling error is one of main errors of silicon microgyroscopes. In order to provide the theories of decreasing or cancelling the mechanical coupling errors, the mechanism of mechanical coupling errors are studied. Based on the dynamic equations and matrix theory, the anisoelasticity, asymmetrical damping and unbalanced mass of a type of z-axis silicon microgyroscopes were analysed, which are induced with the imperfect machining. The mathematic models of mechanical coupling errors were put forward, and the numerical results of mechanical coupling errors were given. The results show that the mechanical coupling errors include errors in-phase with the useful signals and quadrature errors, and quadrature errors are the largest error among the mechanical coupling errors. And the results indicate the major source of quadrature errors is suspension beams mismatched. Finally, the quadrature error of this z-axis silicon microgyrscope sample was tested. The quadrature error is 342.59 º/s, which is in accordance with the analytic results. Restraining and compensating quadrature errors is one key technologies to decrease mechanical coupling errors.- 66
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Published：2020-08-12 -
Aberration and its reduction of Phase reconstructed via digital holography
Abstract：In order to realize three dimensional structure measurement by digital holography, the aberration and its reduction of the phase reconstructed based on Fresnel approximation algorithm are discussed. First, total aberrations of phase reconstructed based on Fresnel approximation algorithm are analyzed, then the digital recording and numerical reconstruction of hologram of phase grating are simulated by computer. Further, the influence from the defocus, the aberration of digital reconstruction light and the depth of the tested samples on the phase reconstructed is simulated and analyzed. It presents the phase subtraction of hologram method to eliminate the phase aberration from the recording light wave and optical parts. Because this aberration has ambiquity characteristic, the experimental results are provided to validate this method. Simulation results indicate that the error from Fresnel approximation arithmetic, the defocus aberration, the digital reconstruction light wave and the wrong unwrapped processing will effect the phase to be reconstructed rightly. High precision phase reconstructed can be gotten when the recording process, reconstruction parameters and the reconstruction method are controlled strictly and selected properly.Keywords：digital holography;three dimensional structure measurement;Fresnel approximation algorithm;aberration analysis;aberration reduction- 43
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Published：2020-08-12 -
Geometric error analysis of laser guiding measurement robot
Abstract：Objective:In order to realize automatic and high- efficient measurement for parts, Laser Guiding Measurement Robot (LGMR) system is established and the robot is made. Eccentricity error of rotating axis for optical trakcer and angle error of the joint line are investigated. Method:First, LGMR tehcnology and its working princile based on the measurement method “laser beam moving, SMR (Spherical Mounted Retroreflector) tracking” are presented . The experimental robot is made according to the technology and the ideal geometry relationship of LGMR is provided. Then the mathematical models of main geometric errors are firstly presented, including eccentricity error of rotating axis for optical tracker and angle error between nominal line to practical line from the middle of two wheels to SMR. Result: an experiment is carried out to both to prove the correctness of the method and to find out the angle error between nominal line to practical line from the middle of two wheels to SMR be 0.13 mm on the x-axis direction, which uses CMM and laser guiding measurement robot system. Conclusion:The results show that two errors have a greater effect on the measurement accuracy, and can be reduced or eliminated by improving machining accuracy of main parts and error compensation. The paper plays an important role in designing and completing motion feedback control system of laser guiding measurement robot.Keywords：error analysis;Laser guidance;Measurement robot;Tracking and measurement- 29
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Published：2020-08-12 -
A New Instrument for Measuring the Roughness of the deep hole surface Based on the ARM920T Circuit Block
Abstract：In the production field of the automobile industry，it is strongly needed a small sized instrument for measuring the roughness of the deep hole surface. This small sized instrument must have these functions: the automatic measurement for multiple points, the complicated data disposal ability, the good quality for graphics display, and sometimes, the rewrite permissibility of the control program to fit different workpiece. The instrument with so many functions made in past, each one have large size and were rather difficult to be used in production field. An effective compact design for the instrument has been realized with the common PC to be replaced by the ARM920T Circuit Block, one type of embedded system. The new developed instrument have not only all of the functions mentioned above but also the advantages such as low cast, high reliability, and especially the small-size. Most of details are introduced these are the integrated design of the measuring instrument, the interface circuit of the embedded system, the general parameter arithmetic for multiple points etc. The new developed instrument can be used to measure the roughness on the inner surface of a hole it’s aperture size is 16~25mm and it’s length is 120~180mm. The measured generatrixs may up to 32 and the points 512. According to the practice use test, the maximum measuring error is less than 5%, however, the new instrument is very adaptive for the industrial needKeywords：Measurement technique;Roughness measurement;Deep hole test;embedded system;ARM processor- 28
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Published：2020-08-12 -
Computer-generated holograms calculation for spatial display of three-dimensional objects
Abstract：Holographic spatial reconstruction technique is an important approach to display three-dimensional(3D) images because the amplitude and the phase of object wave can be recorded in a single hologram, and then 3D image can be reconstructed in free space. Hologram calculation of three-dimensional objects is a key part of holographic spatial reconstruction technique. The basic theories for computer-generated hologram(CGH) calculation of 3D objects were described firstly. Then the principles and key techniques of several typical approaches for CGH calculation of 3D objects were analyzed. Three types of CGHs were calculated for 3D objects by use of tomography approach, Fresnel zone approach and multi-view image synthesizing approach. Subsequently, electro-holographic display experiment was performed by inputting CGH of 3D object calculated by tomography approach into LCR-2500 spatial light modulator and using diode laser with wavelength 650 nm and power 150 mW. Numerical reconstruction results were also obtained from the CGHs calculated by other two approaches. Then the characteristics and limitations were analyzed for the existing methods of three-dimensional CGH calculation. Some key problems associated with hardware and algorithms were also analyzed, and the approaches were discussed for improving the calculation efficiency and the quality of CGH.Keywords：computer-generated hologram(CGH);calculation algorithm;three-dimensional holographic display;numerical reconstruction;electro-holographic display- 46
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Published：2020-08-12 -
New method for repetitive patterned wafer automatic inspection
Abstract：A defect detection method of self-compared template matching based on ESPRIT is presented, which is mainly for the wafer that has same pattern. Firstly, the ESPRIT arithmetic is used to calculate precisely the period of two one-dimensional images and get the size of the building block. We can reconstruct the building block by shifting a window of proper size throughout the image and adding the corresponding pixel values. By averaging over all of the blocks in the image, the amount of noise and the effect of defects are reduced considerably. Standard models are formed by extending standard building block. We compare the original image with the standard models, and the point may be identified as a possible defect if the difference is larger than a threshold. The experiment verifies that this method has high-speed and high-precision, to meet the need of real-time detection. The complexity of this algorithm is O(N to the 3/2th power) and the precision is 0.04 pixel.Keywords：Wafer;Self-compare template matching;ESPRIT arithmetic- 35
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Published：2020-08-12 -
Asynchronous Motor Control System Interface Design Based on FPGA
Abstract：Abstract: This paper designs an asynchronous Motor control system interface based on FPGA. The author designs sampling electrocircuit, keyboard and display interface circuit and encoder in this paper. FPGA functions in paralleling and doesn’t take up time of CPU. Then the performance of the control system is improved largely. The hardware system’s performance is improved by adopting FPGA or combining FPGA and DSP. FPGA can function using program of VHDL. In result, the hardware design feasibility is proved by experiment.Keywords：FPGA;DSP;Sampling electrocircuit;Encoder- 46
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Published：2020-08-12 -
Kalman filter based vision prediction and object tracking method and application
Abstract：In order to make healthcare service robots fluently and flexibly complete some tasks, geometry model has been set up to detect vision information by image processing, and a kind of vision information predict and process method which is based on kalman filter, has been put forward, moreover, a set of predictive and object tracking model has also been provided in light of kalman filter theory. some experiments have been done with these models in a service robot system, and the experiment results show that the object status can been accurately predicted by the provided method, furthermore, the vision information can be quickly detected by prediction and modification with the models and methods. On the other hand, the time lag for vision information feedback can be decreased by using the provided method in service robot system, so the communication between human and robot takes place more fluently.Keywords：Kalman filter;Vision prediction;object tracking;Service robot- 35
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Published：2020-08-12 -
Intercepting of 2D Incoherent OCDMA System
Abstract：The information can’t be effectively intercepted by the conventional energy acquisition when the single user of optical code division multiple accesses (OCDMA) system uses two codes keying the modulation mode. The traditional intercepting way for multi-user OCDMA system is used when only one user emits the signal “1” and the other users emit the signal “0” in the system. The information interception has not real-time characteristic when the quantity of the OCDMA system users is large. Two different information intercepting schemes are designed to resolve the above problems in the two dimensional incoherent OCDMA system. First, it is assumed that the eavesdroppers know enough information such as the mode of en/decoding, the mode of constructing the address code, the transmission rate of the system, the value and quantity of wavebands etc. Then, the energy distribution of optical signals at different time and wavebands is achieved in the OCDMA system by using the advanced optoelectronic detection technique. Finally, the address codes existing in the OCDMA system can be deciphered effectively employing the energy distribution. The functions of the two intercepting schemes are simulated on the software platform of an incoherent OCDMA system that is designed using Optisystem software of Optiwave Ltd. and MATLAB in this paper. The OCDMA system has seven users and seven Reed-Solomon (R-S) codes received randomly. The interceptors can decipher the user signature codes effectively when the two codes keying is employed as the modulation way of the OCDMA system or the multi-users are in existent simultaneously according to the results of analysis. Therefore, the security problem still exists in the 2D incoherent OCDMA system.Keywords：intercepting;2D incoherent OCDMA system;two dimensional Reed-Solomon (R-S) code;address code- 29
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Published：2020-08-12 -
The image fusion arithmetic based on CMAC multi-sensor datafusion model and its performance
Abstract：An arithmetic of image fusion based on CMAC multi-sensor data fusion model is introduced. It can widely spread consubstantial and heterogeneous multi-sensor fusion for its high generalization and approach ability to any image fusion model, well global stability and easy to design; designed an image fusion model experiment to emulate the effect of the arithmetic. The result shows: the fusion result of the arithmetic after training can approach real fusion model more effective than other basic image fusion arithmetics, has less difference to original image, and can act the fusion step real-time.Keywords：multi-sensor info fusion;image fusion;CMAC- 44
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Published：2020-08-12 -
Study on Strategy of Anycast Mode in Networked Measuring & Controlling Platform
Abstract：In allusion to existing problems such as real-time personality and network load balance in IPv4 networked measuring & controlling platform, the new generation network IPv6 is introduced to measuring & controlling platform and the applying strategy of IPv6 new operating mode(anycast mode) in measuring & controlling network is emphatically studied, whose performance is improved in this way. By syncretizing the mathematic model of measuring & controlling anycast mode and reasoning with D-S evidence theory, through combining the network software OPNET with industry scene situation to simulate experiment environment more accurately, the network time delay has been lowered to 0.295 ms from 0.512 ms comparing IPv6 anycast mode and IPv4 original mode, therefore the performance is greatly enhanced. The experiment method introduced in the paper provides a new train of thought for studying new generation measuring & controlling network.Keywords：Anycast Mode;IPv6;D-S Evidence Theory;Measuring & Controlling Platform- 28
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Published：2020-08-12 -
Optimum analysis for structural senor based on coupling effect of magnetic fluid
Abstract：Magnetic fluid is a new kind of nanometer function material, which possesses magnetic character and fluid character. Magnet can levitate among the magnetic fluid, just like staying in vacuum with zero gravity. The new type sensor, base on the levitation character, can avoid the direct mechanical contact, and reduce mechanical friction.The magnetic-current couple effect and the interface effect between the fluid and solid are very evident in the suspension-type magnetic fluid inertia sensor. Base on the classical hydrodynamic theory, the kinematic viscosity equation obtained by fitting experimental data can be solved by associating with the fluid equation, when magnetic fluid can be considered as nonpolar fluid. The key factors to optimize the configuration of the sensor are to increase magnetic-current damp and to reduce the displacement of the magnetic body. The methods of step modeling and setting up integral variable in different field are used to analyze the theory equation, and numeric analysis researches are done on the magnetic-current damp of the objects with different structure. Numerical calculation and experimental result indicate that the viscosity of magnetic fluid, which can be controlled by magnetic density, makes much effect on magnetic-current damp. The structure with grooves can increase the magnetic-current damp and reduce the displacement by compensating the loss of the damp, when it reduce the differential pressure between the sides.Keywords：magnetic fluid coupling;sensor structural;numerical analysis- 37
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Published：2020-08-12
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