bluuebunny/crossref_metadata_2025 huggingface dataset:
The Charge and Discharge Scheme of the Battery in the Solar Lighting System
Authors: Li Xia
Published: November 2012

This article gives the description of the scheme of solar lighting control system. Solar energy is accepted commonly as a green energy because of its unique advantages. In the strong support of the government, the Photovoltaic (PV) generation system gains a rapid development. The stand-alone and grid-connected PV generation systems will be the trend among PV applications. Based on the solar lighting control system, the scheme includes using intelligent control to complete charging and discharging to prevent the battery from being over-charged and over-discharged. Meanwhile the constant current technology is used to drive LED, and the integrated circuit technology is used to implement the solar energy lighting optically controlled self extinguishing.
The Design of Lightning Protection in Automatic Charging Station of the Aviation Airport
Authors: Wang Bao Cheng , Han Gu Yong , Lu Song , Zhou Jun
Published: November 2012

According to the internal specific equipment and facilities in the automatic charging station, with the actual lightning distribution in the automatic charging station, the modern way of lightning protection and the scientific design principle and design thought, we put the lightning protection engineering in the automatic charging station into five parts: the lightning protection of buildings, the lightning protection of power system, the lightning protection of lights monitoring system, the equipotential connection, the common grounding system and indoor shielding. With the characteristics of each part, we design the lightning protection. At last, we use the common ground system to connect with each part of the organic, then forming a comprehensive lightning protection system, so as to ensure the safety of the automatic charging station lightning protection.
Comparisons of OSSDL and VCN Localization Algorithms in 3D Wireless Sensor Networks
Authors: Wu Hua , Liu Yang , Zhang Guang Yuan , Zhang De Jing , Fan Wei Dan
Published: November 2012

In this paper, a comprehensive performance analysis of OSSDL and VCN are presented to explore their performances. Also comparisons with classic DV-Hop and Centroid algorithms are made under different simulation environments. Two aspects of the performance comparison are addressed: positioning accuracy and computational time. VCN has better estimation accuracy than OSSDL, which is much better than that of DV-Hop. Also VCN costs the least localization time.
Sensor Fault Diagnosis Based on Wavelet Transform in Smart Grid
Authors: Sun Xiao Da , Xing Gui Lan , Zhai Ming Yue , Lu Li Peng
Published: November 2012

In the paper, the output signal of sensor in smart grid is analyzed by wavelet, which could detect and diagnose the abrupt fault of sensor. First, the applications of sensor for smart grid are introduced. Then the basic principles of fault detection of sensor using wavelet are proposed. Finally, the simulation results in MATLAB verify the feasibility of the method.
GAAS Semiconductor Laser Ceramics Finish Measuring Instrument
Authors: Hu Xiao Wei
Published: November 2012

China is a large ceramics, gallium arsenide semiconductor laser ceramics finish measuring instrument is convenient, automatic and accurate. It can finish the measurement of the ceramics and glass continuously. This measuring instrument has several characteristics such as miniaturizing, automatically scan, high-precision measuring, strong anti-interference, be easy to use. And, it will have broad application prospects.
Intelligent Battery Charger Based Design Based on MCU
Authors: Ma Fei
Published: November 2012

This paper introduces a kind of intelligent battery charger based design based on MCU. The charger can complete real-time acquisition of battery voltage and current, and the charging process under intelligent control. It can automatically calculate the remaining charging time of the battery and adjust the parameters to adapt to a variety of battery charging. System management circuit also has a protective function, which can prevent the damage to the battery from overcharge and overtime.
Design of LDPC Decoder Based on CMMB
Authors: Wang Jun , He Jing , Xu Xin Yu
Published: November 2012

In this paper, design of a LDPC decoder in CMMB is presented. LDPC decoding algorithms for CMMB are analyzed and the optimal decoding algorithm-Normalized MSA are used to implement the decoder, and the algorithm is simulated to determine the design parameters. A partial parallel architecture based on Normalized MSA algorithm is proposed, and the architecture is simulated with a fixed-point model to determine the best quantification scheme for initial information and intermediate data format.
Experimental Investigation on Supersonic Jet Noise
Authors: Peng Xiao Bo , Li Jia Ming , Hu Chun Bo
Published: November 2012

A systematic study has been undertaken to quantify the effects of jet Mach number and nozzle size on the noise radiated by supersonic jets. All the tests were carried out at an experimental bench of the supersonic jet. Results indicate that the field distribution of supersonic jet screech tones is characterized with very strong directivity. Under the textual experimental conditions, if the jet Mach number remain unchanged, the diameter of nozzle throat increases gradually from 5mm to 8mm or 10mm, and the amplitude values of both the turbulent mixing noise and broadband shockwave correlated noise increase by 2-5dB, and the amplitude value change of the whistler type noise is not obvious, and the occurrence frequency of the whistler type noise decreases by more than 2000Hz; if the jet Mach number increases to 3.0 from 2.0, the amplitude value of the whistler type noise increases by more than 2dB, and the occurrence frequency of the whistler type noise decreases obviously. The experimental measurements of supersonic jet noise provide the sound production mechanism research on the supersonic jet noise with data supports and references and provide the numerical modeling of the supersonic jet noise with validation criteria.
Design of a 10 Gbps VCSEL Current Driver in Active Feedback Technology
Authors: Wang Jin Fei , Chen Ying Mei , Tian Ling , Zhang Li
Published: November 2012

A design of 10 Gbps Vertical Cavity Surface Emitting Laser (VCSEL) driver using 0.18µm CMOS technology is presented in this paper. The core unit of the driver consists of pre-amplify stage and output stage circuit. Technique of three stages differential amplifier with low impedance load and active feedback are employed in pre-amplify stage, and technique of C3A is adopted in output stage to get low power consume and high speed. The simulation results show that the circuit can work at the speed rate of 10 Gbps and maximum of 13 Gbps with a 1.8V power supply. The output modulation current is up to 12.5mA and the power dissipation is 77mW. The chip size is 0.45mm  0.47mm.
Visibility Analysis of GNSS Satellites in Mountainous Area
Authors: Zhang Bo , Zhao Jing , Duan Wen Wei , Yu Long Yang
Published: November 2012

A novel method of analyzing the visibility of GNSS satellites in mountainous area is proposed by taking advantage of target area’s digital elevation model (DEM) data and GNSS almanac. The key point is calculating the obstacle elevation on the basis of target points’ visible range. Simulation results show that both different target points at the same time and same point at different time have different situation of visible satellites on the condition with or without obstacle. On the other hand, this method contributes lots to determine the distribution of pseudolites in mountainous area.
Preparation of SnS Thin Films by Close-Spaced Sublimation at Different Source Temperatures
Authors: Zhan Xiao Ping , Shi Cheng Wu , Shen Xin Jie , Yao Min , Zhang Yan Ru
Published: November 2012

In this paper, thin films of tin monosulfide (SnS) were successfully prepared by close-spaced sublimation (CSS) on the source temperature of 650 °C and 720 °C using SnS powder as a source. The influence of the source temperature on the chemical composition, crystal structure, surface morphology, and direct band gap of SnS thin films was systemically investigated by energy dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), scanning electron microscope (SEM), UV-Vis-NIR absorption spectra, respectively. The results showed that the SnS grain size increased from 3 μm to 20 μm by increase of the source temperature from 650 °C to 720 °C. The direct band gaps of SnS thin films prepared at different source temperatures 650 °C and 720 °C were 1.21 and 1.15 eV, respectively.
Digital PID Controller Design of Electromagnetic Suspension (EMS) System
Authors: Suebsomran Anan
Published: November 2012

This paper presents the digital PID controller design of magnetic levitation application. The highly nonlinear of electromagnetic suspension (EMS) system is hardly and limited the system control subjected to prescribed stability of system. Due to the nonlinear dynamics of system, the linearization of the nonlinear EMS plant is described by linear model. An attraction force about the prescribed nominal operating point of current and air gap positioning is chosen for linearization at a nominal operating point. Such a linear system, digital PID controller is designed for controlling the EMS plant. The system stability is validated by experiment methods. From the results, the reference of air gap position can be tracked with the desired nominal operating air gap position control as shown in practical manner.
Quality Factor Optimization Techniques for MEMS Gyroscopes of Frame Structures
Authors: Si Chao Wei , Han Guo Wei , Ning Jin , Zhong Wei Wei , Yang F.H.
Published: November 2012

MEMS gyroscopes of frame structures are capable of isolating the quadrature error between the drive motion and the sense motion, which is often utilized in current gyroscope design. But quality factors of previous reported gyroscopes of frame structure are hardly over 1000, which are far more less than that of gyroscopes manufactured before with only one mass block for sensing and driving. Although the effectiveness of isolating quadrature errors is proved, the sensitivity is decreased as well as the power consumption is increased for higher drive voltage. Reasons why MEMS gyroscopes of frame structure has low quality factors is pointed out here with a method of anchor loss mechanism, and the energy dissipation is modeled with a 2 degree of vibration system, which tells the relationship between the mass ratio of the inner mass and the outer frame and the spring factor ratio for supporting masses, and the quality factor assess techniques is proposed here. Therefore the admissible parameters of the mass ratio and the spring factor ratio are given, which makes MEMS gyroscopes of frame structures have advantages of quadrature error isolation as well as high sensitivity. In the end, gyroscopes with optimized parameters and reported parameters are manufactured on SOI wafer, and variations of the quality factors as expected proves the rationality of the proposed energy dissipation model in this paper. For Process limitations, quality factors of gyroscopes of frame structures are improved lower than expected, but far more improved than previous reported gyroscopes, and better results should be realized in more mature and stabilized process.
An Optimal Rapid Energy-Storing Design for the Stackable Piezoelectric Power Generation Devices
Authors: Wang Ching Wu , Hsu Tsun Kai , Wu Ji Han , Cheng Jui Hsiang , Yang Chew Wei , Yeh Ti Chun
Published: November 2012

The optimal design for stackable piezoelectric power generation device and its micropower energy storage method is presented in this work. In this configuration, three different arrangement designs of piezoelectric power generation devices were put and compared for obtaining a greater produced output power. Evidence shows that the Sample 2 among the three different arrangement stackable piezoelectric power generation devices could avoid damage to the PZT-5H and achieve a highest instantaneous output power (5.175mW). Moreover, to establish the high efficiency energy storage system, using low power buck converter IC (LTC3588-1) was proposed. The obtained results show that a 15mAh Ni-MH battery could be fully-charged within two hours by utilizing the optimal arrangement design stackable piezoelectric power generation device combining with micropower energy storage system.
Study on the Electronic Ignition System Bench on SCM
Authors: Xu Shan Zhen , Gu Hong Lei , Wang Cheng
Published: November 2012

To enhance the power of the engine and improve the emissions performance, The Intake air temperature signal , knock signal, throttle signal and power supply voltage signal were used as the correction references for the ignition advance angle. According to the parameter characteristics, the schemes of the measurement and control were proposed. The sensors were selected and corresponding parameters were determined. And then parameters of signal processing circuits designed, so that determined the moment of ignition. The experiment proved that the electronic ignition system designed in this paper, can meet the expected demand.
Designing of the Remonte Control Window Cleaning Device
Authors: Sun Meng Qin , Wang Li Chen , Li Shui Qing
Published: November 2012

This paper presents the window cleaning device carried by four-rotor aircraft. The cleaning device adopts the gear drive with the electromagnet; Considering the different shapes of the windows, it is designed there different replaceable cleaning disc; the control system can control the actions of the aircraft and cleaning disc. It meets the requirements of the low-mass, high reliability, high automation, good stability, easy operation to the widow cleaning device.
Transducer Fault Detection of Hot Rolling Screwdown System Based on Sequential Probability Ratio Method
Authors: Li Bao Kui , Yao Xiao Lan , Wu Qing He
Published: November 2012

To solve the fault detection problems of position transducers operating continuously under complex conditions of hot rolling line, and improve the reliability of the control system, a fault detection method based on Kalman filter and sequential probability ratio was presented. Through building the control model of the system, processing the output data of transducers with Kalman filter, and processing the residuals with sequential probability ratio and improved methods, the judgment criterion of transducer fault detection and the method of data reconstruction were given. The simulation results show that, the method can quickly detect position transducer faults, give the reasonable estimated state value, and improve the reliability of the system.
Injecting Mold Protection Method Based on Machine Vision
Authors: Wang Ping Jiang , Xu Chang Jie , Chen Ji Hong , Tang Xiao Qi
Published: November 2012

Aimed at solving the problem of mold damage caused by a foreign body in the mold before mold clamping, this paper proposes a solution, which applies image processing technology such as background updating and the difference image algorithm to solve it. Not only can it judge whether there is a foreign body in the mold but it can also detect whether the product is perfect by comparing the foreground image with the background image at the appropriate time (before mold clamping or after mold opening) and by calculating the qualified rate of pixel in all ROIs (Region of Interest). To eliminate the influence of vibration and of changes in brightness in the surrounding environment on the detecting results, this paper utilizes near infrared illumination technology and the background updating algorithm. In addition, the ROI is set to improve the detecting speed and accuracy.
Lateral Extrusion of A6063 Pipes with a Lost Core of Alumina Powder Bonded with Wax
Authors: Ohashi Takahiro , Thanh Ngoquang , Miyajima Ryosuke
Published: November 2012

The authors have developed a lateral extrusion process with a lost core. The outline of the process is as follows. First, the cavity of a pipe, or a channel material, is filled up with liquid of a low-temperature melting material. The low-temperature melting material is then solidified to become a soluble core of the pipe. The authors call this soluble core the lost core. Next, the material is compressed longitudinally as a composite billet and extruded in the lateral direction. After deformation, the low-temperature melting material is melted and removed. The process can performed in a compression state to control the precise appearance of the product. This study examines a new core material, alumina powder (alumina ball) bonded with wax, as a core material. A mixing methodology for wax and alumina powder is discussed along with the effect of their mixing ratio on the deformation of the pipe.
Investigation on Dynamic Chemical Etching of Fiber Probe for Cell Isolation
Authors: Taguchi Kozo , Okada Jun , Watanabe Nobuyuki
Published: November 2012

A novel single fiber optic tweezers was proposed for cell isolation. Fiber tips were fabricated by dynamic chemical etching. The mechanically cleaved bare single mode fiber was dipped into Hydrofluoric acid containing a protective layer of Toluene at the top. By moving the fiber at variable speeds, a variety of tip shapes could be created. In our experiments, tip angle could be adjusted from 7deg to 55deg. Three-dimensional optical trap of a yeast cell could be formed by the fiber tip with less than 23deg tip.
Molecular Dynamics Simulation of Metal Cutting with Local Hydrostatic Pressure Field Formation
Authors: Uezaki Keito , Shimizu Jun , Zhou Li Bo , Onuki Teppei , Ojima Hirotaka
Published: November 2012

Improving machined surface integrity is one of the important issues in the precision machining. This study aims to develop a cutting tool, which enables to generate a local hydrostatic pressure field in the vicinity of the cutting point to suppress the extra plastic flow in the workpiece, because it is known that materials including metals never cause plastic flow and fracture no matter how much greater hydrostatic pressure field is given. In this paper, a simple cutting tool with planer jig is proposed and a molecular dynamics simulation of cutting is performed as the first step. As a result, it is confirmed that the reduction of the plastic deformation, mainly in the burr formation become remarkable with the proposed model due to the suppression of extra side plastic flow, and relatively high-hydrostatic stress field is formed in the vicinity of cutting point. However, it is also observed that relatively many dislocations are generated beneath the cutting groove.
First-Principles Study of Reaction Process of SiC and HF Molecules in Catalyst-Referred Etching
Authors: Bui Pho Van , Inagaki Kouji , Sano Yasuhisa , Yamauchi Kazuto , Morikawa Yoshitada
Published: November 2012

We have developed a novel abrasive-free planarization method, which we term catalyst-referred etching (CARE). In SiC CARE, Pt is used as a catalyst and HF solution is used as an etchant. CARE produces a crystallographically undamaged and smooth SiC surface. To understand the removal mechanism at the topmost surface of SiC in the CARE process, we performed first-principles reaction path simulations using the Simulation Tool for Atom Technology (STATE) program package. These calculations are based on the density functional theory within the generalized gradient approximation of Perdew et al. The barrier height is evaluated by the climbing image nudged elastic band method. We present simulation results for the initial stages of the etching process. The reaction barrier heights for the adsorption of HF molecules on the first, second, and third Si–C bonds at the edge of the topmost Si-face are 1.8, 1.9, and 1.2 eV, respectively. These barrier heights are reasonably small for a consideration of effect of the Pt catalyst.
Influence of Different Steel Alloys on the Machining Results in Ultrasonic Assisted Diamond Turning
Authors: Bulla Benjamin , Klocke Fritz , Dambon Olaf , Hünten Martin
Published: November 2012

This publication focuses on the ultra precision manufacturing of hardened steel parts with single crystal diamond tools for optical applications such as injection moulding. Nowadays optical steel moulds are nickel plated, in order to be able to machine the surface with single crystalline diamond tools. One technology that has proven its potential for replacing this procedure is the ultrasonic assisted diamond turning technique. This process allows direct machining of hardened steel with single crystal diamond tools, which is conventionally not possible due to the high tool wear. The ultrasonic assisted diamond turning process is applied in order to machine different steel alloys that are conventionally used for mould manufacturing in injection moulding. The goal is to analyze the influence of the steel alloy and the material microstructure on the machining results. The presented analysis show the capabilities of this new technology and opens the door for it to compete with established manufacturing processes, such as the manufacturing of nickel plated mold inserts.
Development of a New Ultra-Precision Magnetic Abrasive Finishing Process
Authors: Zou Yan Hua , Shinmura Takeo
Published: November 2012

To obtain an ultra-precision surface, this research developed a new type of magnetic finishing tool, “Ultra-precision Magnetic Abrasive Slurry”, for a magnetic field assisted internal finishing process. This ultra-precision magnetic abrasive slurry is made to mix simply the super-minute abrasive grains, super-minute globular iron particles, and oily grinding liquid. When the internal finishing was executed, the automatic mixing phenomenon of the Ultra-precision Magnetic Abrasive Slurry is caused, at the same time, super-minute abrasive grains and minute iron particles were uniformly distributed to the magnetic abrasive slurry. It was confirmed that a smooth mirror internal finishing for a SUS304 stainless steel tube is able to be achieved, by using the Ultra-precision Magnetic Abrasive Slurry that consists of the globular carbonyl iron particles (6μm in mean diameter) and diamond grains (0.25~0.75μm in mean diameter) and the oily grinding liquid. In this study, we examined the influence that the rotational speed of the magnetic pole exerted on the finishing characteristic. The results showed that the ultra-precision surface is successfully made, and the surface roughness has been improved from 320nm Ra to 3.37nm Ra .
Surface Generation for Magic-Mirror by End-Milling and Magnetic Polishing with Digitally Functioned CNC Machining Center
Authors: Kawai Ryohei , Aoyama Eiichi , Hirogaki Toshiki , Ogawa Keiji , Sawa Kazuya
Published: November 2012

This paper describes fabrication of a magic-mirror with an extremely small concavo-convex surface, which is invisible to the naked eye. The magic-mirror was manufactured by end-milling with a machining center on the rear of the workpiece after polishing. Incident light was radiated to the mirror surface and the reflected light was projected on a screen. The tool pass by CNC programming show up as image of magic-mirror on the screen. Analysis of the image on the screen indicated completion rate of magic-mirror surface generation. As some experimental result, the integrated magic-mirror production process on the machining center could be achieved by a novel application of on-machine magnetic abrasive finishing and ball end-milling. Moreover, it was found to possible to fabricate a magic-mirror with satiny and continuous-curvature corrugated surface.
Automatic Reverse Engineering Based on Reconstructing Measurement Data in 3D-Lattice
Authors: Tsushima Kiyomoto , Aoyama Hideki
Published: November 2012

Reverse engineering systems are used to construct mathematical models of physical models such as clay model based on measurement data. In this study, we proposed a reverse engineering method which can construct high quality surface data automatically. This method consists of the following steps; The first globally and regionally smooths measured data based on the target shape by fitting quadric surface to measurement data. The second defines quadric surfaces and converts measurement points into 3D lattice points to obtain uniform measurement data density. As the positions of measurement data are converted from coordinate values into 3D lattice points, it is easier to find neighboring points and clarify neighboring relations between surfaces. The third acquires segment measurement data based on maximum curvatures and normals at each point. The last defines NURBS surfaces for each segment using the least square method to average positional errors. In order to validate the effectiveness of the proposed method, we developed a reverse engineering system and constructed mathematical models through basic experiments using clay car model measurement data.
In-Process Monitoring of Tool Behavior and Tool Wear in End Milling by Use of Projection Image
Authors: Yoshimitsu Shinichi , Satonaka Shinobu , Kawano Yoshihiro , Iwamoto Chihiro , Zuo Dun Wen , Yamashita Shunichi
Published: November 2012

This report describes a two-dimensional monitoring system for milling machines using small-diameter tools. Small-diameter tools are used for high-speed milling, and they are indispensable for high-quality and high-productivity manufacturing. However, tool breakage occasionally occurs, and this becomes a serious problem in automated production. This study aims to develop a system for monitoring the cutting state that can prevent tool breakage. The proposed system consists of two charge-coupled device (CCD) cameras, an image processing device, a man-machine controller (MMC), and a machining center with an open computer numeric (CNC). This monitoring system is connected to the machining center by Ethernet. It enables the precise measurement of tool deflection during high-speed milling. In an experiment, we applied this system to the end milling of a steel plate under different cutting conditions, and we examined the relationship between tool deflection and the cutting conditions. In addition, we applied this monitoring system to measure tool wear, and we examined the relationship between tool deflection and tool wear. It was found that the proposed system enabled in-process monitoring of the cutting state and tool wear.
Rapid Planarization Method by Ultraviolet Light Irradiation for Gallium Nitride Using Platinum Catalyst
Authors: Asano Hiroya , Sadakuni Shun , Yagi Keita , Sano Yasuhisa , Matsuyama Satoshi , Okamoto Takeshi , Tachibana Kazuma , Yamauchi Kazuto
Published: November 2012

We have developed a chemical process for atomic planarization of gallium nitride (GaN) using a platinum catalyst and ultraviolet (UV) light irradiation. The process is mediated by a hydrolysis reaction catalyzed by platinum as a solid catalyst. Because the reaction occurs selectively from the step edges, a flat surface composed of a straight step-and-terrace structure is obtained. In the absence of UV light, owing to the low step edge density, the removal rate is quite slow, approximately 1 nm/h. In contrast, under UV light, etch pits are formed on the terraces by photo-electrochemical etching causing an increase in the step edge density. We achieved surface planarization with a removal rate of 9.6 nm/h assisted by irradiation with UV light.
A Novel Batch Fabrication of Micro Parts Using DNA Pattern Recognition
Authors: Yasuda Masafumi , Hayashi Terutake , Michihata Masaki , Takaya Yasuhiro
Published: November 2012

We proposed a novel technique for self-assembly of micro parts by using DNA hybridization. As the demand for MEMS is growing, research on the self-assembly of micro parts is required to achieve fabrication of functional devices consisted of diverse micro parts. Our method has a unique characteristic where the selective assembly can be performed. At the targeted substrate region functionalized by single-stranded DNA, only components functionalized by the complementary one are assembled successfully. This is due to the complementary properties of DNA, which consists of four different bases (adenine (A), cytosine (C), guanine (G), and thymine (T)). A of one strand always pairs with a T of another, and so does C with G. The characteristic enables batch fabrication of diverse micro parts by using several kinds of DNA properly. Therefore, our method can be applied to the fabrication of MEMS. In this paper, in order to verify the feasibility of the automatic positioning using DNA hybridization, we performed a fundamental experiment for addressing polystyrene microspheres (1, 2, 6μm diameter) on the DNA patterned glass substrate.
Actuation Force Measurement Mechanism for Non-Contact Ultrasonic Suspension
Authors: Takasaki Masaya , Chino Shota , Kato Yasuhiro , Ishino Yuji , Mizuno Takeshi
Published: November 2012

In near-field levitation, an object can be levitated vertically upward above vibrating surface of an ultrasonic transducer. In this case, a repulsive force acts on the object. On the other hand, it has been reported that a minute object can be suspended vertically downward under the vibrating surface with a small gap in the air. We call this phenomenon ultrasonic suspension. Under the suspension, an attractive force acts on the object. When an object is suspended, there is restoring force, which pulls the object to the center of the vibrating surface. Our aim is to characterize the actuation forces under the suspension. Simultaneous measurement of vertical and horizontal actuation forces is required. A servo type measuring mechanism was proposed. A 1 DOF mechanism with a cantilever and a voice coil motor (VCM) was fabricated as a prototype. The prototype was calibrated and utilized for measurement of vertical actuation force. The result showed enough accuracy and repeatability. Then, a 2 DOF actuation force measurement mechanism was fabricated. The mechanism was consisted of a base to fix the object and two thin wires to support the base. Position of the base was controlled by three VCMs based on PID control. The ultrasonic suspension actuation forces were characterized successfully.
Development of 2-DOF Hybrid Actuator System
Authors: Okeya Ryota , Aoyagi Manabu
Published: November 2012

Ordinal force-feedback devices mainly employ electromagnetic motors (EMMs), and are excellent at expressing springy sensations. However, it is not easy to express a realistic sense of hardness and roughness using such devices. On the other hand, an actuator system (AS) using multilayered piezoelectric actuators exhibits performance characteristics that are opposite to those of an ordinal AS using an EMM. The objective of the present study is to develop an ideal AS for a haptic display. A two-degree-of-freedom AS utilizing a pair of hybrid AS units, each consisting of an EMM, an ultrasonic motor and a piezoelectric clutch, is proposed and evaluated. Such an arrangement allows the different types of actuators to complement each other, thus compensating for their individual weaknesses. This hybrid AS can expand the range of representable sensations. The results show that the proposed AS can realistically express both hardness and softness by switching between actuator combinations.
Development and Evaluation of Miniaturized 6-DOF Parallel Link Manipulator
Authors: Kobayashi Ryujiro , Tsuboi Ryo , Sasaki Shinya
Published: November 2012

Recently, compact machine tools have witnessed increased demand in the manufacture of small parts with high accuracy. However, miniaturization of these machines poses problems such as decrease in the accuracy and the range of motion. We focused on miniaturizing a parallel link manipulator, which is known to have high rigidity and accuracy. A non-cylindrical link was adopted in the designed manipulator for avoiding collisions among links with an impact drive actuator attached to their side. We confirmed through repeatability measurements that the developed manipulator had sufficient accuracy for handling small electronic parts.
Pivot Turning Measurement of Relative Position and Posture for Moving Robots System Using Stereo-Camera
Authors: Sasaki Tohru , Ushimaru Takayuki , Yamatani Takahiro , Ikemoto Yusuke , Obara Haruki
Published: November 2012

The stereo-camera method is used to measure the positions of robots. In taking the measurements it is important to precisely measure the distance between cameras and the relative posture of the cameras. Therefore, we developed a novel method for measuring a mobile robot's relative position and posture by photographing robots’ pivot turns. A mobile robot system was equipped with a camera and an identification marker that made it possible to measure position and posture with the stereo-camera method when the viewpoint changed freely. One robot photographs the pivot turns of another. As the latter turns, an identification marker on it is used to trace the movement onto an image. The turning robot’s position and posture is determined by the length and angle of the trace. This procedure makes it possible for each of the two robots to obtain their relative position and posture, making the measurement of the stereo-camera method precise. Measuring with a fixed stereo camera is impossible when there are obstacles in the environment and the object being measured moves over a wide range. However, this robot system was able to use the stereo-camera method to expand the measurement range.
Basic Study on Laser Forming Method for Curved Surfaces
Authors: Keisuke Kishida , Nakamura Toshihiko , Aoyama Hideki , Mastushita Naohisa , Ushimaru Akihiko
Published: November 2012

Laser forming, is a plastic forming method using local heat stress which can form sheet materials without dies. Because no dies are required, it enables rapid prototyping and reduced production costs. Many studies have been conducted on laser forming, but almost none on the forming of curved surfaces. The aim of this study is to develop a CAM system for forming curved surfaces by laser. The scanning paths of the laser for forming curved surfaces are based on a method applied in shipbuilding industry. The method uses the maximum and minimum curvature lines as the scanning paths of a gas burner. Since the two curvature lines intersect perpendicularly, they do not influence each other. The scanning speed of the laser for obtaining the required bending angle was determined based on the basic experiments.
Scaling Effects on the Tensile Strength of Fibrous Composites
Authors: Wang Fang , Li Lu , Chen Zhi Qian
Published: November 2012

The primary objective of this paper is to illustrate the effects of weak-link scaling on the tensile behaviour of fiber-reinforced composites. The proposed model takes into account the random nature of fiber strength, which is given by a two-parameter Weibull distribution function. Several hundred Monte-Carlo replications are executed to simulate the statistical strength distributions of the composites. It is shown that probabilistic tensile strength distributions and size scaling is dependent on both the stress redistribution and the fiber strength statistics.
Investigation on T11-Stress for Semi-Elliptical Surface Cracks in Finite Thickness Plates under Remote Tension
Authors: Xie Wei
Published: November 2012

In the present work, three-dimensional finite element analyses have been conducted to calculate the-stress for semi-elliptical surface cracks in finite thickness plates under remote tension. The-stress solutions are presented along the crack front for cracks with values of 0.2, 0.4, 0.6 or 0.8 and values of 0.2, 0.4, 0.6 or 1.0. The current-stress solutions are suitable to be used as the constraint parameter for the fracture analysis.
Investigation of Thermal Damage and the Consequent Fatigue Property of Laser Surface Heat Treated Component
Authors: Tian W. , Zeng C. , Hua L.
Published: November 2012

In order to signify the thermal damage and the influence it has on the fatigue property, a 3D finite element method, as well as experiment investigation, was employed for this research. By the study, it suggests that laser surface scanning can bring about some tensile residual stress and a heat affected zone in the workpiece, so as to lead a fall in fatigue life cycles. Since the fatigue character is affected by the residual stress and the microstructure change, which relate to the laser process parameters, it is expected to draw a scalar variable from stress feature and microstructure parameter to stand the level of thermal damage influence.
Experimental Research on Interlaminal Shear Strength of GFRP Bridge Decks under Simulated Concrete Environment
Authors: Xue Wei Chen , Fu Kai
Published: November 2012

Fiber reinforced plastic (FRP) composite which has high strength, high fatigue resistance, low density, and better corrosion resistances is desirable characteristics for bridge applications, especially decks. According to the ACI 440.3R04, Glass fiber reinforced plastic (GFRP) bridge deck samples were immersed into the simulated concrete environment at 60 for 92d (corresponds to the natural environment 25 years). The results show that, with the time increased, the interlaminal shear strength of GFRP bridge decks decreased significantly. After being exposed to the simulated concrete environment for 3.65d, 18d, 36.5d and 92d, the interlaminal shear strength degradation of GFRP bridge decks were 18.69%, 25.90%, 50.93% and 53.74%, respectively. The micro-formation of the GFRP bridge deck sample surface was surveyed under scanning electron microscopy (SEM), which indicated that with the aging time increased, corrosion pits in the surface of GFRP bridge decks became more obviously and the interface between fiber and resin was severely damaged. Therefore, the degradation of FRP under the simulated concrete environment should be considered in the design of FRP bridge decks.
Vibration Fatigue Behavior of 2024-T62 Aluminum Alloy Cantilever Beam under Different Vibration State
Authors: Hu Hai Tao , Li Yu Long , Wang Jin Li
Published: November 2012

The vibration fatigue experiments of cantilever beam structures were performed to investigate the fatigue behavior of 2024-T62 aluminum alloy. Two types of cantilever beams with various natural frequencies under the sinusoidal excitation were investigated. The initial stress of two types of specimens were set in the same amplitude by adjusting the acceleration of electrodynamic shaker. Based on the stress history recorded by the strain gauge in fatigue test and the Miners liner cumulative damage rule, the fatigue damage of the cantilever beam was calculated. The effect of vibration state on the vibration fatigue behavior of the cantilever beam was discussed. The experiment results show that the fatigue life of the cantilever beam, of which the initial vibration state is resonance, is longer than that of non-resonance. The calculated damage results were in accord with the reduction of the natural frequency measured in experiment. The reduction of natural frequency could be used to evaluate the fatigue damage of structures.
Numerical Simulation of Compression-After-Impact Process of Composite Laminates
Authors: Li Biao , Li Ya Zhi , Li Xi , Yao Zhen Hua
Published: November 2012

The residual compressive strength of composite laminates subjected to low-velocity impact (CAI) was analyzed using the ABAQUS/Explicit package through a two-step calculation. The finite element model was composed of solid elements and interfacial cohesive elements. The out of plane low-velocity impact process was simulated in the first step and the results of which were taken as the input for the second step of the in-plane compression, until the collapse of the laminate. The usefulness of the explicit solution algorithm in dealing with the quasi-static procedure of the in-plane compression was investigated by examining the effect of different initial velocities of the compression loading on CAI values. The simulation results agree well with the experimental results.
Deposition Process and Interface Properties of Electro-Thermal Explosion Sprayed WC/Co Coating
Authors: Cui Xiu Fang , Jin Guo , Li Qing Fen
Published: November 2012

The deposition process and interface properties of electro-thermal explosion sprayed WC/Co coating were studied by numerical simulation and experimental observation in this paper. The variety rule of the deposition particles / metal substrates interface temperature, the critical remelting condition of the substrates surface, and the interface removment speed of deposition particles were numerical simulated by finite element method. Results show that the remelting depth of the substrate increased with increasing spraying particle temperature and particle size. Structures and interface properties of the electro-thermal explosion sprayed WC/Co coating was analysed based on the numerical results. The morphologies, AES patterns, element distributions, TEM micrographs were experimentally observed and compared with the simulatin results. Which show that the finite element analysis is in good agreement with the experimental results, suggesting that the analysis in the present work is reliable.
FE Simulation Methods to Predict Welding Residual Stresses
Authors: Li Li , Asifa Khurram , Li Hong , Khurram Shehzad
Published: November 2012

The purpose of this review paper is to summarize the novel and advanced finite element simulation techniques devised in recent years to predict the welding residual stresses. The finite-element (FE) simulation methods are commonly used to predict the thermal, material, and mechanical effects of welding because of their efficiency and flexibility. This study presents an overview of the research, conducted to more accurately simulate the welding process. Some recommendations and simplification techniques presented by researchers are also discussed in this study which provides a foundation for further development in this field.
Dynamic Anti-Plane Behaviors on Two Dissimilar Piezoelectric Media with an Interfacial Non-Circular Cavity
Authors: Song Tian Shu , Li Dong , Zhang Ming Ju , Zhou Yue Fa
Published: November 2012

Dynamic anti-plane behaviors are studied on two dissimilar piezoelectric media with an interfacial non-circular cavity subjected to time harmonic incident anti-plane shearing. Based on Greens function and conformal mapping method, the dynamic stress concentration factors at the edge of the non-circular cavity are obtained by applying the orthogonal function expansion technique. Numerical cases about two dissimilar piezoelectric media with an elliptic cavity are provided with different elliptic axial length ratio, different wave number and different piezoelectric characteristic parameter. The calculating results show that dynamic analyses are of importance at lower frequencies and larger piezoelectric characteristic parameters.
Galvanic Corrosion of Titanium/Cu-Ni Alloy/High Strength Steel Multiphase Material System in Seawater
Authors: Wang Chun Li , Li Qing Fen , Wu Jian Hua
Published: November 2012

The galvanic corrosion behavior of titanium/ Cu-Ni Alloy / high strength steel in multiphase material system has been studied under open circuit conditions using a zero-resistance ammeter (ZRA) in seawater. After the tests, the surface morphologies of the samples were detected by SEM. These results have been compared with results estimated from the polarization curves according to the mixed potential theory (imposed potential measurements). Results showed that Galvanic corrosion behavior of titanium (TA2)/Cu-Ni Alloy (B10) / high strength steel (921A) fulfill the mixed potential theory, 921A acts as the anode and bothTA2and B10 act as the cathodes. The overall galvanic reaction is mainly governed by the anodic oxidation of the 921A.
Investigation into Damage of Stainless Steel Mesh/ALPlate Multi-Shock Shield under Hypervelocity AL-Spheres Impact
Authors: Guan Gong Shun , Pu Dong Dong , Ha Yue
Published: November 2012

A series of hypervelocity impact tests on stainless steel mesh/aluminum plate multi-shock shield were practiced with a two-stage light gas gun facility. Impact velocity was approximately 4km/s. The diameter of projectiles was 6.4mm. The impact angle was 0°. The fragmentation and dispersal of hypervelocity particle against stainless steel mesh bumper varying with mesh opening size and the wire diameter were investigated. It was found that the mesh wall position, diameter of wire, separation distance arrangement and mesh opening had high influence on the hypervelocity impact characteristic of stainless steel mesh/aluminum plate multi-shock shields. When the stainless steel mesh wall was located in the first wall site of the bumper it did not help comminuting and decelerating projectile. When the stainless steel mesh wall was located in the last wall site of the bumper, it could help dispersing debris clouds, reducing the damage of the rear wall. Optimized design idea of stainless steel mesh/aluminum plate multi-shock shields was suggested.
Transient and Steady State Regimes of Fatigue Crack Growth in High Strength Steel
Authors: Toribio Jesús , González Beatriz , Matos Juan Carlos
Published: November 2012

This paper analyzes the propagation of fatigue cracks in pearlitic steel in two forms, hot rolled bar and cold drawn wire. The experimental procedure consisted of fatigue tests on bars under tensile loading, using steps with decreasing amplitude of stress and constant stress range during each step. The curves plotting cyclic crack growth rate versus stress intensity factor range show a main steady-state regime preceded by transient paths. The steady-state regime is associated with the curves of the Paris regime. The cold drawing process improves the fatigue behaviour of steel by retarding the cyclic crack growth rate, and the propagation rate is not dependent on theR-ratio. The transient branches allow one to calculate the plastic zone size, considering that they are a consequence of the overload retardation effect at each step change, and a unique expression is fitted as a function ofKmaxΔKproduct and of the conventional mechanical properties.
Impact Identification in Composite Stiffened Panels
Authors: Ghajari M. , Sharif-Khodaei Z. , Aliabadi M.H.
Published: November 2012

A number of small mass and large mass impacts on a sensorised aircraft stiffened panel were numerically simulated. Sensor signals and the contact force history were recorded during each impact. A significant difference was noticed between the small mass and large mass impacts with respect to the contact force. To distinguish between these two types of impacts, the Fast Fourier Transform was performed on the sensor signals and a categorisation criterion was defined. Finally, two separate Artificial Neural Networks were trained to approximate the peak contact force for each type of impact. It was found that the performance of these ANNs were better than a single ANN trained for both small and large mass impacts.
Dynamic Response Analysis of Lining Structure with Primary Defects for Tunnel under Moving Train Loading
Authors: Cui Yu Ping , Sun Wei Ze , Dong Jun , Dong Fei
Published: November 2012

Considering the background of vibration engineering of lining structure of subway tunnel with primary defects under moving train loading, and according to the measured information of a dynamic loading spectrum of subway in Beijing, dynamic response of the lining structure with differently primary defects caused by neighboring tunnel construction has been investigated for different cases including one-way and two-way trains in this paper. The results show that the curves of dynamic time history analysis are similar with each other for displacement and stress under different cases with differently primary defects. The peak value of displacement and stress under the case of two-way train is much larger than that under the case of one-way train, and the structure primarily depends on tensile strength of concrete in safety. Under the case of one-way train with primary defects would there be no defect by vibration loads.