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Issue 4 ， 2000
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Locomotion methods of mobile microrobots
Abstract：Microrobotics is an important branch of MEMS. Many microrobots have been invented and they will be widely used in the future. The ways of designing and manufacturing microrobots are different from those of ordinary robots. Because of their narrow working environments and special usage, it is almost impossible to apply conventional actuators, transmission mechanisms and executive mechanisms to microrobots. According to their locomotion methods, microrobots can be classified into four types(legged type, wheeled type, worming type and swimming type). Some prototypes based on each locomotion method are discussed and their novel mechanisms are analyzed. The miniaturization of actuators is the key to the design of microrobots. The conclusion is reached that innovative and efficient locomotion methods can lower the demand on micro actuators.Keywords：MEMS;microrobot;locomotion;actuation- 52
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Published：2020-08-12 -
Methods of high resolution optical measurement for surface profile
Abstract：The methods of optical measurement for surface profiles with high resolution even sub nanometer are presented generally. In the paper, three optical methods for measuring surface profile, optical probe, interferometric method and near-field optics method, are mainly described. Optical probes include scanning confocal microscopy and defocus error detection. Interferometric methods include TOPO interferometric profilometer, Nomarski microscope, Heterodyne profilometry, double focus profilometer and coaxial profilometer. Near field optics methods include scanning near-field optical microscopy and photo scanning optical microscopy. By reviewing and contrasting the principles, characteristics and problems with these methods, the trends of high resolution optical measurement for surface profiles are described.Keywords：surface profile;optical measurement methods;high resolution- 59
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Published：2020-08-12 -
Technique of image grabbing and processing in ellipsometric imaging system
Abstract：Ellipsometric imaging, which has been developed during recent years, is a kind of technique for visualizing the superthin layer distribution and surface structure. It not only supplies a new tool for studying molecule biology, bio-medicine(especially molecule bio-medicine)and bio-molecule materials science, but also has promising applications in disease diagnosis and examination of micro electronic elements and nano-materials. In order to improve the quality of images, Expanding Pixel Bit-depth and Fast Grabbing and Time Averaging, as well as Averaging Over Pixels are proposed. Above methods have been proved effective in the system with some experiment results. These methods may be used in some similar imaging systems.Keywords：ellipsometric imaging;image grabbing;image processing- 55
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Published：2020-08-12 -
Method of fast video interpretation
Abstract：The video interpretation is an important component of modern optical measurement equipment. In order to increase the efficiency of video interpretation, a new and quick interpretation method, including automatic interpretation and semiautomatic interpretation, is studied and presented. In automatic interpretation, the image stored in hard disk of computer is decomposed through median filtering and two value segmentation, and the barycenter of target is automatically computed, then the output of target undershoot error is given. However, under the special conditions of large target and low contrast, the precision of automatic interpretation is relatively low, it is necessary to use semiautomatic interpretation method to improve the interpretation precision. The experiment results in this thesis show that the hybrid of automatic interpretation and semiautomatic interpretation as a new interpretation method can greatly increase the efficiency and precision of interpretation.Keywords：Video interpretation;semiautomatic interpretation;automatic interpretation;manual assist automatic interpretation;image processing- 68
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Published：2020-08-12 -
Edge feature extraction method for image
Abstract：The boundary of the object is an important feature for an image. Because of the influence of the noise the edge feature extraction is a basic and difficult problem. In order to restrain the noise of background, improve the edge accuracy of detection, this paper presents an edge feature extraction method for image by the multiscale characteristic of wavelet transform. Using the method of mutual energy cross for edge features in variety of scale and accuracy, this method can restrain noise and recognize edge. Simulations show this method is valid.Keywords：Image;edge feature;wavelet transform;multiscale analysis;mutual energy cross- 77
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Published：2020-08-12 -
Simulation of orbit external thermal flux of a space optical remote sensor
Abstract：It is very important to simulate reasonably the orbit external thermal flux of a space flying object and space optical remote sensor through thermal equilibrium experiment in order to investigate them for thermal effect, verify thermal design, and evaluate the capacity of their thermal-controlling system to adapt the space environment. A simulation and computation method for orbit external thermal flux is described, and especially the technique and the device for a space optical remote sensor are presented in connection with structure, surface property, distribution of external thermal flux and thermal equilibrium experiment requirement. And parameters of heating sheet are determined on the basis of computation and verification employing computer software. As a result, it provides an approach for simulating the orbit external thermal flux of a space flying object and space optical remote sensor.Keywords：space flying object;space optical remote sensor;Orbit external thermal flux;simulation method- 41
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Published：2020-08-12 -
Constitution of guide star catalog for star sensor
Abstract：Guide star catalog is significant for identifying star map, acquiring final attitude. The capacity, store manner, store content and read manner of the guide star catalog are key factors which influence the time and efficiency of star map identification. The paper introduces the method which adopts spherical matrix method for storing and reading guide star catalog, and elaborates the selecting rules and storing content on guide stars. Using spherical matrix method, the rough region of guide stars can be searched rapidly in all celestial sphere, that storing midyear average position and the angular distance between guide star pairs can further reduce sight position transformation time and star map identifcation time.Keywords：guide star catalog;average position;sight position;angular distance between star pair;spherical rectangles method- 45
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Published：2020-08-12 -
Application of centroid sensing method in real time autofocusing system used in space camera
Abstract：Auto-focusing technique is an important method for ensuring high quality image of space camera.In order to refocus in-flight for space camera,a precise auto-focusing system with auto-collimatic method is introduced, in which two pentagonal prisms are substituted for a large mirror,a low power laser is used as the light source and CCD as photoelectric converting device. This system has compact structure and reliable properties. The resolution of the whole measuring system has been improved by the use of signal processing techniques in centroid sensing method such as choosing threshold and data smoothing,the experiments show that the measuring resolution is less than 5μm.Keywords：centroid sensing method;space camera;pentagonal prism;autofocusing- 48
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Published：2020-08-12 -
Straight-line scanning analysis and aberration correlation of holographic scanning disk
Abstract：The paper described the principle of holographic scanning disk. The constructions of the holographic scanning disk with fixed spatial frequency distribution and variable spatial frequency distribution were given. The condition of straight-line scanning generated by holographic scanning disk was analysed based on the method of hologram phase and phase transfer function. It derived the relation between parameters of recording sublet hologram of holographic scanning disk. The result of straight-line scanning of holographic scanning disk were presented based on the difference between the constructed and reconstructed wavelengths and the method of aberration correction. The effect of disk wobble and decentre on the scanning characteristic of holographic scanning disk was analyzed. Finally, the paper introduced the design of holographic scanning disk with variable spatial frequency distribution.Keywords：holographic scanning disk;straight scanning;aberration correction- 81
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Published：2020-08-12 -
Analysis of the capacity of energy transmission for piezoelectric bimorph
Abstract：The electromechanical conversion, consisted of the capacity of energy transmission, the effectiveness and the maximum mechanical output energy of piezoelectric bimorphs under three constant loading conditions(force, moment, pressure)are quantitatively analyzed based on its cantilever constitutive equations. As a result, the electromechanical conversion mostly depend on the transverse electromechanical coupling factor k 31, and they are largest in the case of a moment, smaller in the case of a force, and smallest in the case of a pressure. These conclusions give directions for designing the structure of piezoelectric bimorphs actuators.Keywords：piezoelectric bimorph;effectiveness of actuator;electromechanical coupling factor;microactuator- 57
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Published：2020-08-12 -
Distributed MS CAD system based on server group
Abstract：In the research field of MS-CAD, one essential problem is how to develop function modules belonging to different disciplines and to make them an integrated tool to fulfill design and simulation tasks at system level. The popularization of Internet and maturity of distributed processing technology give a new approach to solve this problem. A novel distributed CAD software structure based on server group is proposed in this paper, a CAD system designed according to this schedule could fulfill the task of design and simulation of MS at system level. At the same time it is very easy to be expanded as an open system with pretty good intelligent capability.Keywords：server group;distributed;Microsystems;CAD- 56
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Published：2020-08-12 -
Design of servo-feed mechanism of ultra-precise lathe
Abstract：The paper analyses the error sources which contribute to the kinematic accuracy of servo-feed mechanism of ultra-precise lathe. On the basis of this, this paper brings on some methods for eliminating the error source by modifying machine structure of the servo-feed mechanism instead of increasing the manufacturing accuracy of the lathe′s components. Those methods mainly inlcude applying multi-throttle air-lubricated hydrostatic slide guide and mounting a float unit on the screw pair. After applying those methods to the servo-feed mechanism of the ultra-precise lathe, the kinematic accuracy of the servo-feed mechanism can meet the requirements of ultra-precise Machining.Keywords：ultra-precise machining;air－lubricated hydrostatic slide guide;multi-throttle;float unit- 49
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Published：2020-08-12 -
Analysis of tool breakage in CNC manufacturing using wavelet transform
Abstract：The paper introduces the features of the wavelet transform in contrast to the FT and FFT. Combining with tool breakage signal, the fast wavelet transform-Mallat algorithm is analyzed. It analyzes the technique of extracting the spindle motor current of the Machining Center, correspondingly, points out that Hall current sensor is a very efficient way. As the signal of tool breakage is transient, wavelet transform is used to analyze the signal of tool breakage in CNC milling and a successful example of the method is adduced to get the characteristics of the signal of tool breakage. Experimental results show that the method of MRA can not only locate the position in time-frequency domain, but also easily monitor the manufacturing system. The method can be applied effectively to signal processing of monitoring tool breakage.Keywords：wavelet analysis;tool breakage;DC current signal- 60
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Published：2020-08-12 -
Warning and orienting technology for threaten laser
Abstract：The threaten laser from battle field is summarized. It includes laser tactics reconnaissance, weapon or laser control and guide weapon. The principle of laser detection is discussed, which includes the way of laser capture and receive, the catalog of laser detection, the feature of laser detection optics system and laser detection sensor. Warning and orienting technology for threaten laser is analyzed and two useful designs of laser warning apparatus are described in detail.Keywords：laser detection;laser warning;orienting- 63
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Published：2020-08-12 -
Influences of sample frequency and delays on tracking system
Abstract：Based on the TypeⅡ system, influences of sample frequency and system delays on tracking system are analyzed theoretically. Relationship between system sample frequency, system delays, open loop cut-off frequency and phase stability margin is given in formula and curves. It provides a simple and effective method for designing and analyzing a tracking system. The simulation convinces that the result is correct. This method can be used to analyze other systems.Keywords：sample frequency;phase margin;system delays;tracking system- 59
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Published：2020-08-12 -
Constraint condition selection method in camera calibration
Abstract：At present, least squares algorithm is generally used to calibrate cameras. Constraint condition selections have a great effect on estimating precision. On the basis of analysis to former selections of constraint condition, a new constraint condition selection method is rpesented. Computing formulas of parameters are got after mathematical derivation. The algorithm avoids solving nonlinear equation. After constraint relations between parameters are observed and studied, a constraint condition is selected using the property that orthogonal matrix ensures Frobenius norm to be unvarying. Errors are distributed in the light of constraint relations between parameters, so precision of camera calibration can be improved.Keywords：camera calibration;computer vision;machine vision- 78
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Published：2020-08-12 -
Key problems of raising the printing speed and improving the graphic printing quality of stylus printer
Abstract：The key techniques of raising the printing speed and improving the graphic printing quality of stylus printer are studied. The relation equation between the stylus beating frequency and the motion speed of printer head is derived from the analysis of the mechanism of stylus printer and validated by experience. According to the derived equation, raising the stylus beating frequency and the motion speed of printer head simultaneously and properly controlling the first beating time of the stylus in each row printing, one can effectively raise the printing speed and improve the graphic printing quality of stylus printer.Keywords：stylus printer;stylus beating frequency;motion speed of printing head;graphic printing quality- 66
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Published：2020-08-12 -
PID controller tuning method for improving performance
Abstract：A PID controller design method that achieves high performance for a wide range of linear self-regulating processes is proposed. Satisfactory dynamic characteristic can be obtained for processes with various dynamics, including those with low and high-order, small and large dead time, and monotonic and oscillatory responses. The method is developed based on a second-order plus dead time modeling technique and a closed-loop pole allocation strategy through the use of root-locus. The model is proven to be effective for a wide class of processes, and the model is able to generate peaks in those of oscillatory processes. Different closed-loop poles are selected according to the damping ratio and dead time, and simple formulas are provided for the calculation. Simulation show satisfactory results.Keywords：frequency response;linear systems;model reduction;PID control;tuning- 70
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Published：2020-08-12 -
Surface shape error theoretical analysis of two curvature lenses milled and ground
Abstract：After two-curvature lenses have been milled and ground, the curve on vertical section is a real circle, and on the horizontal section is a complicated curve, the paper presents the complicated curve equation by analyzing the shaping movement. Comparing ideal circle with the complicated curve, it gives the surface shape error calculation of two-curvature lenses, then it calculates the surface shape error by computer. The result shows that the surface shape error is diminished when the lenses turn radius equals 176.66mm, the bigger the emery wheel diameter is, the farther the turn angle of emery wheel would leave the range of around 30?. It can offer theoretical basis for selecting rational parameter of the machine tool.Keywords：two-curvature;lenses;machine tool;shaping movement;errors;Precision- 42
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Published：2020-08-12 -
Establishment and verification of measurement model based on neural networks
Abstract：Aiming at the difficulty of the model establishment of indirect measurement, a new method of measurement model establishment based on radial basis function neural networks is presented. In order to obtain a high modeling precision when the size of training sample is small, the center of radial basis function is decided by clustering results of the training sample, then, the effectiveness of this method is proved by application examples.Keywords：measurement model;radial basis function;neural networks;clustering- 54
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Published：2020-08-12 -
Measurement theory and implementation method of source Wheatstone bridge in laser high speed resistance trim
Abstract：The measurement theory of source Wheatstone bridge in laser resistor trim system are described, the implementation method of high speed resistor trimming is proposed, by means of comparing the voltage output from the two high precision 16 bit D/A convertor and the voltage output from galvanometer. The digital high speed resistor measurement is implemented. The factors of affecting the measurement precision are analyzed . The method is valuable to the high speed resistor measurement and control.- 73
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Published：2020-08-12 -
Design of contactless integrated card dining system
Abstract：An intelligent consumption system based on contactless integrated card and Novell network is proposed. It introduces in detail the principle and major function of basic mode, network structure, data library management and software developing tools, and presents the solving method of some critical techniques. In respect of advancing principle, using conveniently, lively interface between machine and people, and nicer safety, it is more advanced than the contact integrated card. The contactless integrated card system can be applied widely to intelligent consumption system, auto recognizing system and so on, and it has good popularizing value.Keywords：contactless integrated card;dining system;Novell network- 54
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Published：2020-08-12 -
Mixed programming method based on Windows95
Abstract：As we develop a complex software, only using one kind of developed-tools can not fit our demand because of its limits. This paper introduces a mixed programming method based on Windows95, which is very important and practical. By this method, programmer can use multi developed-tools such as VB, VC++ and ASM in a program in order to take their advantage adequately, and can meet design demand,moreover, improve developing efficiency and save developing time. This paper analyzes this method in detail, and provides an actual application example at last.Keywords：Windows 95;mixed programming;VB;VC++;ASM- 50
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Published：2020-08-12 -
Memory mapping technique of IBM PC/AT
Abstract：The memory mapping principle based on IBM PC/AT ISA bus and its address decision are discussed in detail. Taking the interface of TMS320C32 and IBM PC/AT on stationary Fourier spectrometer real-time data processing system for example, the memory mapping techniques of both 8 bits and 16 bits data transmission are proposed. It speeds up the rate of data transmission, improves the ability of communication between the host and slave.Keywords：ISA bus;memory mapping;segment address;data transmission- 48
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Published：2020-08-12
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