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In recent years, compliant mechanisms have attracted more and more attention of scholars at home and abroad, and achieved rapid development. The introduction of flexible variable stiffness design in flexible mechanism can not only improve the safety of human-computer interaction, but also improve the adaptability of the machine. Because the ID-LEJ (Inside-Deployed Lamina Emergent Joint) is a kind of LEMs and has very good bending performance. In this paper, the rotary ID-LEJ flexure hinge is proposed based on ID-LEJ hinge, to maximize the bending capacity of the hinge. In order to realize variable stiffness of rotary ID-LEJ, four sliders are arranged in the rotary ID-LEJ to change the stiffness of the hinge. The variable stiffness of the hinge is analyzed by Equivalent system and Finite element analysis. When the slider is symmetrically divided (yl1=yl2=yr1=yr2) the bending equivalent constant of the variable stiffness hinge varies continuously from 30.8 n · mm / rad ∼ 38.2n · mm / rad. And when the slider is asymmetrically distributed (yl1=yl2≠yr1=yr2) The bending equivalent constant of the variable stiffness hinge varies continuously from 30.8n · mm / rad to 34.2 · mm / rad. The results show that the variable stiffness performance is very flexible and stable.

Ulva usually attached to aquaculture rafts, rocks, and floating objects. Previous studies have shown that the world's largest green tides in the Yellow Sea originated from the attached Ulva on rafts. However, a large biomass of Ulva thalli has recently been found attached to Littorina sp. (periwinkles) in the Subei intertidal zone, but it is rarely observed on Bullacta exarata, Portunus sp., and other intertidal benthic animals. The population density of Littorina sp. on the Zhugen sand ridge is approximately 39.2 specimens/m2. A maximum of seven Ulva macroalgae were attached to one periwinkle, and an average of 1.24 Ulva macroalgae were attached to each periwinkle. To determine the contribution of epizoic Ulva on Littorina sp. to floating green tides, these macroalgae were identified with a molecular biology method using internal transcribed spacer (ITS) sequences. Results showed the Ulva attached to Littorina sp. comprised just one species, Ulva flexuosa. Epizoic Ulva attached to intertidal benthic animals in the Zhugen sand ridge does not appear to be the main source of the green tide (the only dominant species is Ulva prolifera) outbreaks in the Southern Yellow Sea.

MOEMS packing architecture has been a major driving force for miniaturization of fiber optical components and optical communication devices. By using of bulk micromachining technology, V-grooves and micro-pits can be fabricated on a silicon wafer for coupling micro laser diode to fiber or fiber to fiber, and finally integrating into the small modules on chip packages. Because many factors, such as photolithography, material property, wet chemical etching process and operator's skills will influence the geometric accuracy, a precision measurement instrument is needed for in-situ inspection of V-grooves suitable for the critical passive optical alignments. This paper reported a novel 3D confocal profile measurement system for in-situ inspection of the depth of multi-channel V-grooves.

3-D profile confocal optical microscopy is a newly developed 3-D profile metrology and has widely applied in many kinds of 3-D shape inspection fields. Present 3-D shape measurement system used in confocal optical microscopy is single point measurement. Point by point detection to finish a 3-D profile inspection is considered a time consuming method and isn't suitable for large area measurement especially for high resolution measurement. This paper elaborated on a fiber-array confocal 3-D imaging system to improve measuring speed. In confocal measurement system, light source acts an important effect on system accuracy and repeatability. Light source fluctuation can cause a large error for high resolution 3-D shape measurement. This paper presents a novel system construction to solve the problem of light source fluctuation. The system design is compact and the construction is reasonable.

Confocal 3-D imaging technique is a newly developed technique and widely used in many fields of research and development. It is to utilize light intensity sensitive measuring technique. Confocal 3-D profile measurement system is widely used in high resolution inspection. For high precision 3-D imaging inspection in confocal measuring system, light source acts a very important role in system resolution and accuracy. In order to improve measuring repeatability and stability, to reduce measurement error, and to lower the light source stability requirement and cost, this paper studied light source fluctuation effect to confocal imaging measurement; deduced depth response model function; analyzed system error caused by light source fluctuation; and presented a new scheme to reduce the affection of light source fluctuation. Theoretical analysis and experiment result verified that light source fluctuation should be considered and eliminated in very high resolution confocal 3-D shape measurement system.

With the increasing demand for micro-products and bioengineering research, resolutions of profiles with micrometer or even nanometer scale are becoming commonplace. In addition development of large integrated manufacturing systems and the real time life science growth and adaptation need high-speed display and real-time inspection. Single point measurement is time consuming method with large area profile and micrometer resolution. Thus there is a need for a fast 3-D measurement system with high resolution. This paper presents a short overview among optical 3-D shape measurement techniques, and concentrates on the confocal method. Based on the properties analysis, a novel multi-channel 3-D topography measurement system was proposed. The feasibility and the construction of system were described A unique new structure of fiber coupled confocal system is put forth to solve present problems confronted in confocal system. This system can meet the current demand of high resolution and fast 3-D measurement.

Moire method is an effective way to measure full field deformation. In this paper, the atomic force microscope scanning moire method and micro-moire interferometry method are proposed to determine the deformation in micro-area. The measurement principle and techniques are discussed. The two methods are applied to measure thermal deformation in a BGA (ball grid array) electronic package component. The shear strain (gamma) xy at the solder site is determined. The experimental results including the adaptability of these two methods are compared and analyzed. The results show that AFM scanning moire and micro-moire interferometry methods are effective ways to measure the deformation in micro-area with high sensitivity.

A theoretical model of far-field interference from a sphere has been established, and its applications have been investigated. When two coherent parallel laser beams shine on a smooth sphere surface from opposite directions, the reflected lights form interference fringes at far field. The fringes have hyperbolic shapes and are not uniformly distributed. This paper derives a method for calculating the path-length difference between two parallel reflected lights, analyzes the interference field, and discusses reasons that cause the fringe density variations. A formula for calculating the highest orders of interference fringes is also provided. A method for using a spectrometer, CCD camera, and computer to measure the sphere diameter is demonstrated. The results agree with those from an Abbe comparator. The theory and methods are also suitable for measuring diameters of smooth cylinders.