Measurements of fine particles and tiny bubbles with micro and nano size in a flow are important measurements for manufacturing of electronic devices and aseptic medical drugs. In-line measurements of diameter of particles and bubbles using interference patterns have been proposed. In this method, scattering light of a particle and a bubble occurred by radiating a laser generate an interference pattern. Signals of the patterns are measured by photodiodes. In the present study, we measured interference patterns by a high-speed video camera in order to confirm generation of interference patterns of fine particles and tiny bubbles. In addition, we discussed distinguishability between fine particles and tiny bubbles. From these experimental results, an interference pattern was confirmed for a bubble with 100 jam in diameter. Besides, change of a number of light and dark rings corresponding to diameter of measured bubbles was proposed. However, we were not able to observe clear distinctions of interference patterns of particles and bubbles.

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Under the microgravity environment, liquid can be treated without container due to weightless. Therefore physical properties of a material are expected to be measured with a high accuracy. In viscosity measurement of levitated droplet, there are some methods. However, there has been no method to measure viscosity of droplet which ranges from 0.1 [Pa s] to 100 [Pas]. The final goal of this study is to establish new viscosity measurement technique with levitated droplet. A droplet is levitated by using electrostatic levitator, and induced to rotate. It is confirmed that viscosity affects breakup of levitated droplet due to rotation. So, new technique is discussed by applying measurement principle of Liquid Filament Rheometer.

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To evaluate liquid phase heat transfer, temperature field of the liquid phase around an isolated boiling bubble was measured using Mach-Zehnder type interferometer. As a result, macroscopic thermal flow field in boiling was observed. However, in the vicinity to the liquid-vapor interface, expected thermal boundary layer indicates evaporative heat transfer was not measured, and the lack of the spatial resolution of the used interferometer was shown. Thus the measurement system was improved to obtain temperature information of thin thermal boundary layer and spatial resolution was improved to 2.75μm/Pix. Finally, a temperature field around the bubble was captured using renewed measurement system, and the measurement of the evaporative heat transfer near the interface was successfully achieved.

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This paper describes potentiality of design education by using force sensors device. The device is like a 3D-mouse (PHANTOM) which gives a feeling of object recognition. Generally, designing like an idea-sketch is the first process for manufacturing and it is very important to use the digital data for modeling. FreeForm modeling with the PHANTOM is introduced as a tool for design education. The SensAble Technologies PHANTOM product line of haptic devices makes it possible for users to touch and manipulate virtual objects. In this paper, potentiality of design education using the FreeForm product is discussed and it is indicated that the FreeForm system is effective for 3D clay digital-modeling.

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This study aims at understanding a tensile test visually. Therefore, the deformation volume presentation system of modification of the tensile test using an image was developed. The strain gauge was used for the confirmation of accuracy and comparison with the finite element method was also performed by carrying out comparison with the value of a simulation. Template matching was used for measurement, and the subpixel was also introduced in order to raise the resolution of an image. Moreover, the program which measures the appointed domain was also created.

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The authors manufactured the robot which was used by Theo Jansen Mechanism. Automatically, these robots detect each other position and form a line and do march. They manufactured the robots for improvement of their skills and increase of children who become like robots. This paper is written about how to manufacture the robot.

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In Japan, the high school curriculum guidelines by the government, so called Yutori education, were performed from the 2003 fiscal year. Then, the students who enter in a university from the 2006 to 2016 fiscal year are educated by this guideline. Therefore, the university needs to educate the student in consideration of the influence of Yutori till the 2021 fiscal year, when even the graduate school master's course is considered. In this lecture, mathematics ability of the university student who received Yutori education is made into the theme. A presenter reports their actual condition and the correspondence to the university student in the department of mechanical system engineering faculty of engineering Gunma University to which he belongs. In order to improve a mathematics ability of the student of the faculty of engineering, the countermeasure from the first academic year is fundamentally required. As a realistic countermeasure in the department, the student is made to understand the details of the contents which are not regularly learned at both a high school and a university, and the text in which self-learning is possible is prepared for the student.

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The author gave instruction manufacturing and flying returnable toys to teachers of elementary schools. They are boomerangs with three papers, boomerang stunt planes, boomerang papa* cups, paper boomerang dragonflies. The contents of the courses and their responses are introduced And then, key words of responses and criticism of lesson are discussed.

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The authors have analyzed children's toys and manufactured it. In this time, the authors analzed AlsomitraMacrocarpa. It is plant's seed. It has form like glider. So it can fly a long distance. The authors were interested in it. The autors found its toy and analyzed of loci of it.

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PET bottle rocket is widely used as a plaything in the handcraft lessons for children. However, principle of the thrust generation is same as a real rocket system, and we have elucidated its unsteady thrust characteristics in detail. In the research process, it was recognized that PET bottle rocket has various attractive natures from an engineering education viewpoint. In the present paper, potential ability of the PET bottle rocket as a teaching material of engineering education is discussed.

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The mechatronics educational program for the university students who are studying in the technology and industrial teacher training course is discussed in this paper. The targeted students are not used to the soldering or the use of a PIC microcomputer, and also have less knowledge about mechatronics. The aim of our research is to provide the short term studying program of mechatronics for the technology and industrial teacher training course students. The teaching robot system in which a student is able to study mechatronics in step by step process through its fabrication is utilized in this study. This paper will present the results of class work and robot fabrication.

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Tokyo Tech High School of Science and Technology has been developing the curriculum of robot education. "Electronics Control Practice" using a single-board microcomputer "Arduino" is studied in a second grader's lesson. This single-board microcomputer can treat a digital input/output and an analog input/output easily, and can study motor control and liquid crystal display. "Arduino" is also used in robot research in a third grader's lesson "Project Study", such as remote control of robot arm by using master slave system and development of a transformation robot which can run three wheels and walk on two legs. This paper describes these educational practices using "Arduino"

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The phenomena with relation to fluid mechanics are often taken up in books on science for popular readers. However, the explanation on principle of them has been described under misunderstood knowledge on fluid mechanics in many books. It seems the reason that the many authors are not understood fluid mechanics enough. Also, there is the further reason in the descriptions involved mistaken explanations in many books. In present study the mechanism of transmission of so misunderstood explanations has been considered, and the diffusion of them has been investigated. It is also examined and proposed how to prevent the transmission and diffusion of the misunderstood knowledge.

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A special three-year educational program for master-course students was conducted at Graduate School of Science and Engineering in Saitama University. It covered various fields of mechanical engineering and focused on advanced manufacturing for optical industries. To achieve the educational goals, "Global Nano Fabrication (GNF)" course was set up and thirteen students were selected each year from those in Mechanical Engineering and Mechno-Robitics courses. This program was supported by RIKEN, regional industries and Saitama Prefecture. It was characterized by two internships; one was conducted in companies and the other was conducted in RIKEN. Two intensive lectures by instructors from companies and researchers from RIKEN were also arranged.

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We have developed the design support system, "Design Support Navigator", for young mechanical engineers. Moreover, we have put this design tool into- Hitachi group's companies through a seminar for design of screw fastening with the use of one. However, in the traditional seminar, it was found that several students couldn't understand the lesson. There, the curriculum has been improved to move out a barrier to comprehension. Namely, main improvements were that exhaustive lesson of design procedure and review of exercise after the seminar. Additionally, operation screen of the design tool was improved for engineers to operate easily. It was shown by questionnaire after a seminar that the improved curriculum was very effective.

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In this report, global engineers (GlE) are grouped into several categories, and education and qualification required to be a variety of high-level global engineers and the role of industry and economy focused education, among others, are discussed.

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To save the Resources needing to our life , such as Energy, Material, Cost, Time, Man Power, can not be establish by only The Stoicism, preferably be added to above ICT way, can contribute by lesser the resources and shall become the most invention in the human life providing the continual evolution.

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Generally, mechanical structures are demanded highly safe to withstand earthquakes. Therefore, exact evaluation of failure of structures has been required. According to studies on failure of piping, the load due to earthquake is a cyclic loading. The relationship between failure and the energy is evaluated, examined by paying attention to the Energy Balance Method said to be effective as an earthquake response analysis technique in the present. Moreover the Energy Balance Method has aimed at the generalization of the earthquake-proof evaluation technique. This study carries out failure experiments using simple single degree of freedom models having various cross sections. Whether it influences energy that either the section modulus or the moment of inertia area requires for failure is examined as a parameter of the shape of cross section by using the model of tens of kg order.

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In the operation of industrial plant, it is important to grasp the condition of the pipe. The problem pipe has is pipe wall thinning because of erosion or corrosion. In general the damage is measured with the ultrasonic thickness gage now. However, it is difficult to take an accurate measurement of location thinning and investigate the entire pipes. In this study, we pay attention the pipe's surface vibration by fluid vibration of tube, and suggest that the measurement vibration analysis for piping integrity. The damage can vary the properties of vibration. Measurement hardware is acceleration sensor for the reduction of maintenance and repairs. The analysis method is Fast Fourier Transform. In this way, it is expected to improve evaluation of piping integrity.

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We use the Shape Memory Alloy (SMA) devices to improve the durability of an electronic circuit board under a vibration environment. In order to investigate the effect of a SMA device, we conducted vibration suppression test of an electronic circuit board. Examination contents did a sine wave vibration test, a compound environmental test, and durability test. At the time of normal temperature, the SMA washer showed 12% of oscillating control effect compared with the brass washer. Moreover, destructive process of an electronic devices and a mounting board bonding link by vibration was shown.

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In recent years, follows a lift at home and abroad steadily increases with the addition of a handicap accessible and high rise buildings, many accidents have been reported to cause a shortage of inspection. Assessment carried out for the health of the lift, are urgently needed to develop a structural health monitoring system to support the inspection. In this study, using a wire rope tester using magnetic field measurements are made wire rope being used in elevators, health diagnostics is performed to diagnose the type and degree of damage such as broken wires wear or corrosion of the response waveform consider the possibility of developing the system. From rust and wear flaw response waveform obtained experimentally, and verified that it can detect wire breakage and other damage.

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The stent used for angiostenosis coarctation supports vascular wall by conveying, developing and detaining to the affected part using a catheter, and secures a blood flow. Many stents made from stainless steel until now were used. However, since the flexible adaptation to various forms by that the conformity to the body is high and the superelastic effect is possible, many Ni-Ti alloys are used nowadays.When the purpose of this research inserts a Ni-Ti stent into a blood vessel, it is examining the structure which was excellent in durability by conducting FEM in the breakage portion by the repetition by pulsation and bending and twisting.

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There are several researches estimating friction between road and automotive tires during driving. Elastic rubber structure of tires deforms beyond measurable range of conventional strain sensor. This study aims to fabricate large-strain sensor which exceeds conventional gauge in terms of strain range. Number of conventional wide range strain sensor uses carbon nanotubes(CNT) as either (i) CNT added elastic resin or (ii) CVD grown CNT array. Most of them are using resistivity change as sensor output-Either type has its disadvantages such as long delay in response or complicated and high cost fabrication process. The sensor in this study has inter-digital electrodes made of thin CNT layer which work as capacitor. The electrode pattern is printed on PDMS rubber sheet utilizing photo lithography which does not require any high cost process or advanced technology. Sensor fabricated in this way showed wide range of corresponding strain with short delay.

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For the further space developments, unmanned robot system to capture space debris is necessary. Micro-capsule type actuator using hydrogen storage alloys was proposed to drive the robot system. Although the proposed actuator is small and light weight, it can drive with high power by exhausting hydrogen gas included in the capsule. The driving behavior of the actuator was analyzed by FEM, and the optimal size of the actuator was determined by the FEM analysis.

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This Paper describes a research with the vibration control of a beam structure, and piezo elements are used as a sensor and an actuator. The control system with piezo elements is called Smart Structure and is used for the aerospace field and precision components as examples. Locations of piezo elements are decided according to the result of strain measurement experiment with stain gauges. And 2-degree of freedom dynamical model is created by the modification of -natural modes of the structure. Finally, LQG regulator is created and is implemented to the structure which is excited by harmonic excitation. As a result, the control effect is confirmed in both time response and frequency response.

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Advanced self-healing agents were investigated for mullite matrix composites. Mullite matrix composites are expected to protect self-healing agents from the excess oxidation because of its low oxygen diffusion rate. Silicon based alloys were made expectations on good affinity with mullite. From its melting point and oxidation stability against oxygen in mullite matrix, Fe-Si, Ti-Si systems alloys were determined to be the most attractive candidate for advanced self-healing agent. Furthermore, it was found that mullite/TiSi2 composite ceramics has a lower self-healing temperature of 460℃, corresponding to 760℃ lower than that of mullite/SiC composite.

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Alumina fiber reinforced alumina with the SiC interlayer was developed. The composite can heal the delimitation of the fiber/matrix interface by using the high temperature oxidation of the SiC interlayer. Healing at 1300 ℃, corresponding to the optimal self-healing temperature of SiC particles dispersing self-healing ceramics, gives rise to the large strength recovery as well as the alumina fiber degradation. Thus, the composite healed at 1300 ℃ was lost the large deformation ability. On the other hand, it was found that healing at 1000 ℃ for 100 h can lead to the complete strength recovery without alumina fiber degradation.

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An impact load on a thick carbon fiber reinforced plastic (CFRP) plate usually causes a dent. The dent results in a decrease of electrical resistance in the thickness direction. Our previous papers demonstrated the effect of the dent in the measurement of electrical resistance change of a thick CFRP plate subjected to impact loading. The present paper focuses on the mechanism of decrease of the electrical resistance caused by a dent. Experiments were performed to measure local fiber volume fraction after various loading. The observation revealed that the dent is made by plastic deformation of the matrix under compression loading at an impactor. This deformation cause slight increase of fiber volume fraction. The slight increase of the fiber volume fraction causes significant increase of electric conductance in the thickness direction.

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This paper describes a disturbance stability of vehicle dynamic control systems. The Active Font wheel Steering (AFS), the Active Rear wheel Steering (ARS), and Direct Yaw moment Control (DYC) is compared. Disturbance torque or disturbance lateral force assumes that it is inputted into a vehicle. Disturbance zeroing control is applied to the vehicles system, and the target is controlling to become yaw rate; y=0. Computer simulation is carried out and shows that all the systems have converged on y=0. The convergence time of DYC was the shortest.

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This paper describes an investigation of the non-linear filter that can change a high frequency gain and phase delay independently. In the driver-vehicle closed-loop system, there is the report that the phase delay of the vehicle has the optimal value and deteriorates the vehicle maneuverability even if too large or too small. However, there is a relationship in a linear system that a high frequency gain becomes larger whenever a phase delay becomes smaller. We can not judge the driving difficulty caused by the phase delay or high frequency gain. In this investigation, we tried to design the non-linear filter that can solve the trade-off of a high frequency gain and phase delay. We applied this non-linear filter to the driving simulator and investigated the transition of ease to drive by using the evaluator's steering angle data and the subjectivity evaluation of the vehicle maneuverability.

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Recently, pedestrian collision avoidance systems have been launched in automobile markets and they might not be able to avoid collisions in some specific circumstances, such as when a pedestrian appears at very close distance and high velocity. To prevent collisions with pedestrian, it is necessary to develop an active safety system which considers not only overt collision risk but also potential collision risk. Therefore, this study aims to develop Hazard-anticipatory driver assistance system to prevent collisions with pedestrian considering potential collision risk. This paper describes the design of a potential hazard area detection method in intersection with poor visibility by using LIDAR as a part of the systems.

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Among road accidents, lane departure accidents show highest fatality rate, and lane departure prevention system has been developed. However, since the current lane departure prevention systems are based on lane marker detection by a camera, the systems cannot be operated in urban area which has complex environment. The objective of this study is to develop lane departure prevention system which can detect road boundary in urban environment by using LIDAR. The LIDAR detects the curbs on both sides of the road path. As a first step of the study, this paper shows that it is feasible to detect road boundaries by using LIDAR and the lane departure risk can be quantitatively evaluated by using the index, Time-to-Lane-Crossing .

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A gasoline engine mini car (Subaru R2) was converted to a two person ride electric vehicle. At first, the gasoline engine was removed after testing the running performances. Next, the designs of a battery, a DC motor, a motor mount were carried out. Finally, the running tests of the fabricated electrical vehicle were carried out, and the performances of the fabricated electrical vehicle were compared with the performances of the gasoline engine vehicle.

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We have developed a single person operated fuel cell vehicle with lkW fuel cells (micro FCV) and a high-power DC/DC boost converter used for the power train. This paper describes the performance evaluation of the DC/DC converter, and hybrid systems with fuel cells and batteries.

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We have developed a single person operated fuel cell vehicle with lkW fuel cells (micro FCV). The designs of the drive train using two motors with gears were conducted. This paper describes the performances of the drive train system.

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We have developed a single person operated small fuel cell vehicle with lkW fuel cell (micro FCV), and have participated the World Green Challenge 2011. The aim of our research is to develop an utility vehicle on a public road. This paper describes the driving methods and the running results in the competition. The running results showed that the average velocity was 28km/h between 400W and 600W.

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This study evaluates the response performance of the motorcycle with the rider control model. The effects of the rider control model gains on the response performance of the motorcycle-rider system are examined by computer simulation. The lateral displacement gain rarely affects the response performance if the gains on the yawing and rolling angles are moderate values. If either the yawing or rolling angle gain is small, the weak directional or attitude stability causes the less damping response. On the other hand, if either gain is large, the coupled oscillation of the yawing and rolling angles is occurred.

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To enhance the safety and reliability of railway transportation, it is one of the most important tasks to check the track condition frequently and accurately. This paper describes the track condition monitoring technique using the car-body acceleration. In an inverse problem to estimate track irregularity from car-body acceleration measured by in-service vehicle, state space model and Karman filter is applied. As a result, it can be concluded that track irregularity in longitudinal level is able to estimate with desired precision.

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The environmental noise and the wear of rail occur, because the railways run while rolling wheel on the rail. Recently, the railway truck without the sleeper and the ballast is being used. The occurrences of the rolling noise and the wear of rail may be different from the previous generation. Therefore, in this study, the effect of the sleeper and the ballast were examined through experiments and analyses, when a wheel runs on the rail in passing through the connection point. As a result, the damping ratio of the truck with sleeper is higher than that without sleeper. And it was shown that there was a setting condition of ballast for the increase of damping ratio. Furthermore, it was shown that the natural frequency of rail was changed by the displacement of wheel on the rail.

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This paper presents the results of experimental study on the electrostatic separation of mixture consisting of binary plastic and paper. The principle behind the separation technique is based on the difference in Coulomb force acting on the particles after corona charging. The charged particles are fed into the center of the space between the four electrodes. The falling trajectory of highly charged particle is different from that of lowly charged particle. Therefore, the plastic mixtures can be separated as a result of the different positions to which they fall. The separation tests were performed on a sheet-like sample containing PET and PS plastics and papers. In this study, PET particles are separated from the mixture. It was found that the separation efficiency depends on the projection angle and the applied voltage to the electrode.

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As a method to separate two different types of plastic, an electrostatic separator using roller type electrodes was developed. The separator consists of a plate electrode and four roller electrodes. An electric field is generated in the space between the plate and the roller electrodes. The separate experiment was performed on a sample containing ABS (Acrylonitrile-Butadiene-Styrene) and PS (polystyrene) plastic. ABS and PS particles become positively and negatively charged, respectively. When the charged particles are fed to the separator, ABS and PS particles are attracted to a plate and roller electrodes, respectively, because of Coulomb force. Therefore, the plastic mixture can be separated as a result of the difference of the trajectories. It was found that the high separating accuracy can be obtained. In addition, the analytical method was proposed to predict the recovery of particles.

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In this study, theoretical and experimental studies of electrostatic separation of plastic mixtures were conducted. The separator consists of four cylindrical electrodes. The principle of the separation is based on the difference between Coulomb forces acting on plastic particles. The separation of a mixture of polyethylene(PE) and polypropylene(PP) particles was studied. All particles were obtained from shredded cap of plastic bottle. An analytical solution based on the charge distribution for particles is presented. It is show that the approach in this study is effective for estimating the recovery of plastics.

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This study aims to clarify effects of machining conditions for wire electric discharge on machining speed and machined surface integrity. These results are related to develop the electric conductive ceramics as forms, which possess excellent mechanical properties. These also contributed to the optimum condition for wire electric discharge machining for electric conductive ceramics. Electric conductive ceramics plane plate, which was manufactured by Nippon Tungsten LTD, used for this experiment. Each average machining speed measured under each wire EDM condition as electric conductive ceramics plate was cut in 9mm straight. Each worked surface of the plate was applied for SEM observation and surface-roughness evaluation. Experimental results showed that effects of wire EDM machining conditions on average machining speed and surface roughness of ZrO2-WC. Machining speed decreases with increase of the periodic time. It also rises with increase of pulse duration and Duty Factor. It appears that roughness on worked surface depends on Duty Factor.

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Aluminizing, siliconizing, boronizing, chromizing and carburizing were performed on gray cast iron substrates by using pack cementation processes, and their microstructure, hardness and tribological properties were investigated. Pack cementation coating films except for carburized specimen exhibited micro-Vickers hardness higher than non-coated gray cast iron substrate. The friction coefficients of aluminized, boronized and chromized specimens exhibited higher than that of the non-coated substrate, whereas the friction coefficient of carburized specimen exhibited smaller than that of the non-coated substrate. Moreover, the specific wear rates of aluminized and carburized specimens were higher than that of the non-coated substrate. On the other hand, wear rate of boronized specimen was much smaller than that of the non-coated substrate.

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This paper describes tribology in micro-scale order that is influenced by low friction force caused by low normal load. Recently, micromachines have been used in various fields. Tribolobical property in micro-scale such as micromachines move is known to be different as compared to macro-scale tribology. The aim of this research is to clarify microtribology and evaluate it. We selected diamond stylus tip and glass wafer as specimens in this research. In this experiment, friction force between two specimens is measured by using scratch tester. Besides, we observed friction groove and measured its depth with SEM. In conclusion, some knowledge about microtribology has clarified.

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Surface texturing techniques have been focused as one of the methods to reduce friction. Previous studies show that surface texturing has the effect of lubricant reservoir, trapping wear debris under boundary and mixed lubrication regimes, and modifying hydrodynamic pressure under hydrodynamic lubrication regime. However, the mechanism of friction reduction phenomena on textured sliding surface has not been clarified yet. In this study, we observed the interference patterns on sliding surface with block-on-disk type testing apparatus in order to try to observe dimpled surface under the sliding contact. Dimples were produced by laser processing. PAO and hexadecane were used in order to investigate the effects of dimpled surface from boundary to hydrodynamic lubrication regimes. We proved that friction property was improved by dimpled surface and observed that the specimen attitude was influenced by dimple dimensions.

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In this paper, vibration and noise in wet friction systems with paper-based materials as seen in wet clutches in automatic transmissions were investigated experimentally. The experimental setup was composed of clutch plates and shaft of wet clutches. The circumferential, radial, and out-of-plane acceleration of a clutch plate and the noise around clutch plates were measured. As a result, it was shown that the frequency range from 400 to 1000 Hz of high noise level agreed with that of high acceleration level, and that dominant frequency of 810 Hz in noise agreed with that in radial acceleration of clutch plates.

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