With the development of IoT and communication technology, household electric appliances can be remote-controlled by the communication network, which makes our life more convenient. However, there are still many problems in daily life. For example, many families dry their laundry on the veranda. But an unpleasant experience might happen if we went outside and the laundry is still on the veranda. In addition, a few housewives are troubled with no place to dry their laundry during the rainy season, which might cause inconvenience in the whole family in that period of time. Therefore, this research will illustrate a veranda rain shelter system utilizing an Arduino and some sensors which can assist in fixing problems that have happened in our daily life.

Recently, traffic accidents caused by the drowsy driving are frequently featured by medias. The system capable of catching the sign of drowsiness and alert the driver to prevent him from drowsy driving is highly demanded. The purpose of this research is to evaluate the impact on driver drowsiness by the cabin thermal environment, especially focusing on the effect during winter season and evaluate the effect of the cooling stimulation within 3℃ difference around the initial temperature.

In this research, we measured the blood pressure time history data of the subjects by using continuous sphygmomanometer changing the temperature inside the simulation chamber. From the measured data, one of the evaluation indexes of drowsy level, i.e. RR interval was extracted to evaluate the impact on driver drowsiness by the cabin thermal environment. Moreover, we evaluated the drowsy level change of the subjects when cooling stimuli was loaded. In detail, we calculated the index of parasympathetic nerves-- nHF(Ratio of HF among Component over 0.04Hz), the index of sympathetic nerves-- LF/HF(the ratio of Low Frequency Power Spectrum Intensity and High Frequency Power Spectrum Intensity), then, evaluate the effect of the cooling stimuli by comparing nHF，LF/HF values prior to and after loading cooling stimuli.

According to the Japan Statistics Bureau, 35 million people are over 65 years old (28.7% of the country population)⁽¹⁾. To assist ambulation, T-shaped walking sticks are frequently used, since they are easy to get in different kinds of stores. In this paper, the results of usability experiments using T-shaped sticks are reported. Thirteen healthy man (age 21.46±0.50 body weight 56.7±7.3 kg and height 170.7±6.0 cm) participated in this experiment, in which we analyzed relationships between easiness to grip and the stick grip shapes by using sensory evaluation and statistics. As a result of using multiple regression analysis, significant differences were shown for each stick Py length and shaft perimeter. In conclusion, three important points must be considered for designing a T-shaped walking stick: (1) The length of the grip must exceed the width of the hand when grasped, (2) design for a Py/Ny ratio of 1.88, and (3) the circumference of the shaft should not be increased. By applying these rules, we consider that it is possible to design a stick grip shape that is easy to grip.

With the advancement of information technology, haptic devices are receiving attention over the last few years. However, transmission of detailed information, such as character information, by using haptic devices has not been achieved. Therefore, in order to establish a technique to transfer character informatoin by a tactile feedback, we have developed a haptic feedback system that is capable of presenting vibro-tactile stimulation on dorsum of hand. We examined three key parameters of the vibro-tactile stimulation: position, direction, and time difference, by psychophysics experiments and revealed their effects on the accuracy of information recognition. Finally, we derived an optimum condition between vibrator and skin in a dorsum of hand.

An AC electroosmosis (ACEO) micropump has been required for μ-TAS, lab-on-a-chip, and so on due to its miniaturizable simple structure to generate a water flow without mechanical moving parts. To design ACEO devices, an ACEO mathematical model is needed, however, the previous model has large discrepancy between the simulated and measured velocities when physical parameters are used. To overcome the problem, in this study, a new mathematical model was proposed considering the forming time and the nonlinear capacitance of the electric double layer and FEM simulations were performed for a simple ACEO convection generator. The device was fabricated using MEMS fabrication process. Through comparison between the simulated slip velocities and the measured ones, the effectiveness of the proposed mathematical model was confirmed. Finally, the mathematical model was applied to the design of the SS-ACEO-MP (Square pole - slit electrodes ACEO micropump) and the higher flow velocities than those of the previous device were estimated.

The weatherability of the practical use plasma actuator electrode, produced by Asahi Rubber Inc., was studied using the natural snow wind facility of the Hokkaido University of Science. NACA0015 test blade of the chord length c of 300mm and span width of 790mm was manufactured using a 3D-printer. Wind tests were down under the angle of the attack of the blade was fixed at 15 degrees and flow velocity of both U=3m/s and 5m/s. PIV measurements were conducted on various plasma actuation conditions using natural snowflakes as the tracer. It became clear some snowflakes were jumped from the suction side of the blade and flow away. The trace of the snowflake is not completely coincident with the airflow particle path. When the actuator was driven under the condition of St=fc/U=1 and Duty=1%, movement of snowflakes was controlled the most effectively and snowflakes could not reach the trailing edge of the suction side of the blade. Snow deposit tests were also carried out. It became clear that snow deposition was started from the trading edge of the blade and after reaching the leading edge of the blade, it spread over the whole suction region of the blade. Under snowfall conditions, the practical use plasma electrode has suffered no damage and operated stably.

LEDs are widely used because of their low power consumption and long life. Since LEDs are severely deteriorated by heat, it is necessary to take measures such as heat dissipation with heat sinks. In this study, cooling is performed using a flow induced by a PSJA (plasma synthetic jet actuator). The induced flow thins a temperature boundary layer formed by heat dissipation of LEDs. We investigated the cooling temperature when the PSJA was driven at a certain burst frequency and several duty ratios. It showed good linearity with the cooling temperature at a duty ratio of 60% or less up to 10 seconds after driving, and the linearity collapsed after a while after driving.

Large-eddy simulations on a separation control flow around a NACA4418 airfoil have been conducted. In the separation control, a vortex-generator type plasma actuator (VG-PA) has been adapted with a burst actuation and a continuous actuation. Effects of the burst frequency and the burst ratio on control effects have been mainly investigated. In addition, the effect of the VG-PA length has been also investigated. The aerodynamic performances are improved with the increase of the burst ratio. The controlled flow fields by the VG-PA with the burst actuation show that they are like a hybrid flow between the flow of the intermittent SP-PA with a burst actuation and that of the VG-PA with a continuous actuation. The aerodynamic performance is improved for the longer VG-PA.

Tri-electrode plasma actuator (TED-PA) is an active flow control device utilizing the ionic wind coming from atmospheric discharge. It consists of exposed a DC and an AC high voltage electrode, a dielectric plate and a covered ground electrode. For high flow controllability, the design optimization is needed to maximize the ionic wind from the DC electrode. In this report, we experimentally investigate the influence of the AC discharge condition on the DC discharge and the DC ionic wind. For this purpose, the discharge photograph and thrust of jet is investigated. The results are compared with those of two-electrode actuator which has only the AC and DC electrode. As a result, it is found that the DC discharge and thrust enhanced by the AC barrier discharge and increasing the AC frequency is effective for the enhancement. However, high frequency application induce jet from the AC electrode and the AC jet collide with the DC jet so thrust decrease.

For installation of a dielectric-barrier-discharge plasma actuator (DBD-PA) on a small fixed-wing UAV, a wind-tunnel experiment using a NACA23015 three-dimensional wing model with a chord-length of 200 mm and an aspect ratio of 3.5 was conducted. The chord-based Reynolds number was set to 126,000. The flow-control capability was evaluated by time-averaged pressure measurement. Under this condition, a stall occurred around an angle of attack of 13 degrees, and flow-control experiments with a DBD-PA were conducted at an angle of attack of 19 degrees as a deep-stall angle and the capability of flow control was evaluated with changing the span-wise DBD-PA length. Results show that the flow-control capability is almost unchanged from the span-wise DBD-PA length of 80 % to 92 % (the maximum length in this experiment), and decreases abruptly at the whole span region below the length of 80 %, rather than changes linearly. This result is important knowledge for the installation of DBD-PA on a fixed-wing UAV.

Plasma actuator can form a three-dimensional flow by devising the shape and arrangement of the electrodes. The plasma actuators with a complicated electrode shape can be manufactured with the photolithography technology. However, this method has some issues to be solved such as high cost, a large number of steps, and a limitation on the size of the device to be manufactured. In this study we focused on printing technology toward an adaptable flow design. Since the electrodes can be wired on the substrate by using the printing method, the flow structure induced by the plasma actuator can be freely designed. We fabricated some plasma actuators by an inkjet printing technology. The stable surface DBD was observed in the printed plasma actutor as observed in the conventional plasma actuator made of copper tape. The thrust was larger with the printed plasma actuator than that of the plasma actuator made of the copper tape. In addition, a uniaxial multi-electrode plasma actuator was fabricated to form a three-dimensional vertical jet. The fabrication of the plasma actuators by the inkjet printing technology may be able to create various flows.

Integrated Dielectric Barrier Discharge Plasma Actuator (DBD-PA) can accelerate induced flow successively by electrohydrodynamic force and it is expected to generate stronger airflow than single type DBD-PA. In recent research, it has been found that the induced flow becomes stronger as the number of electrodes of integrated DBD-PA increases, however, not been verified how strong an induced flow can be generated. Therefore, the basic performance of annular integrated DBD-PA is investigated in this study to verify the performance potential of integrated DBD-PA. The annular integrated DBD-PA used in this study has eight rows of electrode pairs arranged on the surface of an acrylic cylinder and it can successively accelerate induced flow along the cylinder circumference. We carried out induced flow velocity measurement by PIV technique and power consumption measurement via V-Q Lissajous method to evaluate the performance of annular integrated DBD-PA. As a result, it is found that induced flow velocity increased by 60 – 140% and power consumption per electrode unit increased by 73 – 238% compared with single electrode type DBD-PA.

This study covers the flow over a step object in order to clarify the effect of the generated vortex by the plasma actuator on the flow control features. A dielectric barrier discharge (DBD) plasma actuator is mounted on the surface of the step front edge and driven with a periodic on and off mode (burst drive). The pressure on the step surface and velocity field around the step were measured. In consequence, the surface pressure varies with the burst frequency and it recovers toward upstream at a certain frequency. Also, the position of the reattachment on the step surface changes.

Manufacturing and distribution industries handle a lot of kinds products, whose shapes and materials become a wide variety. It is required that the end-effectors of automated systems to be able to work for those numerous products. Jamming grippers can change their shape along the objects, being versatile and easy to operate. On the other hand，it is difficult to miniaturize their entire systems because jamming grippers need vacuum pumps in order to operate pressure. We focus on electro-conjugated fluid (ECF) because it can generate characteristic flow with only electrodes and high voltage. This study proposes a new type of microgripper with a hydraulic power source using a jet flow of ECF. The gripper is integrated power source of ECF into its side for downsizing. Excluding the conductors, the size is width 13 mm and length 26 mm. This paper reports on the design and the results of the performance evaluation．

Environmental contamination such as marine pollution has been regarded as an important problem recently. In this research, we focus on the flow of water generated by a predation of jellyfish and have developed a jellyfish soft robot that collects rubbish floating in the sea. A shape memory alloy (SMA) actuator was used for the jellyfish soft robot as the driving source. The SMA actuator was manufactured with SMA wire of 0.15 mm in diameter and silicone rubber. The SMA actuator was also attached to the cap of jellyfish soft robot. We tried two types of underwater experiment that first one is measurement of cap bending displacement and response time for performance evaluation and the other one flow visualization using fluorescent yellow paint. Experimental results showed that the water was flowed under the cap of jellyfish soft robot when its cap was closed and the water was flowed inside the cap of jellyfish soft robot when its cap was opened. In this paper, we report the rubbish collection method, the design and experiment of the jellyfish robot.

In this research, the method of improving the performance of the moving mechanism for snow using the Archimedes' screw is examined. The cylinder diameter of the screw has a great influence on the load capacity and propulsion performance of the proposed mechanism. Therefore, changes in loadage and propulsion performance of the proposed mechanism with the cylinder diameter doubled compared to the previous studies were examined by numerical analysis based on the mechanical characteristics of snow obtained from actual measurements. As a result, it was clarified that loadage and propulsion performance were greatly improved compared to the previous studies.

In recent years, microfluidic devices are expected to be applied in a wide range of medical and chemical fields, and higher performance is required for pumping and mixing. In this study, A new Mooney-type piezoelectric actuator consisting of a bimorph piezoelectric actuator and a metal cap was applied to a Y-shaped microfluidic device, and its performance was evaluated by a piezoelectric-fluid coupled analysis. As a result, compared with the conventional bimorph piezoelectric actuator, we confirmed about 19 times improvement in the liquid transfer amount and verified the superiority of the new actuator.

Pneumatic rubber artificial muscles are composed of a rubber tube and fibers and have features such as lightweight, shape adaptability, and high power-weight ratio. Therefore, artificial muscles have been used in devices used around humans. The developed artificial muscles are fabricated by using Shape Memory Polymer (SMP) fibers and they can change their drive form after fabrication. Previously in our laboratory, the SMP fibers were fabricated by cast molding and there were restrictions such as workable time and mold size in the procedure. Therefore, in this paper, a continuous fabricating process is established using solution type SMP. In the process, cotton fibers are dipped in SMP solution and it is passed between two rollers which make the surface of fibers smooth and penetrate SMP solution in the fiber. The SMP solution is cured in a drying furnace. The fibers are pulled and rolled around a bobbin continuously by a motor. As a result, we successfully developed the fibers that satisfies the conditions.

The McKibben artificial muscle and the Straight Fiber type artificial muscle with SMP fiber are fabricated by using a braiding machine. These artificial muscles realized different driving by changing the initial shape.

This paper presents a contact force control without a force sensor in piezoelectric bimorph actuators. A feedback control system using a high-resolution force sensor is important to achieve high-precision force control by suppressing the nonlinearities in the piezoelectric actuator. Contrary to that, sensorless control is required to reduce the cost and space utilization of micro- and nano-systems. In this paper, the contact force is calculated based on using the input voltage to the actuator and the voltage of a series-connected capacitor and resistance. A mechanical model and an electrical model are used as an estimation equation of the contact force. The two parameters used in the equation are turned based on preliminary experiments. A force feedback control system is designed based on the estimated force signal. The proposed sensorless control approach has been verified by conducting experiments using a piezoelectric bimorph actuator and different contact objects.

Soft actuators, or artificial muscles, based on conducting polymers, constitute the base for the development of promising polymeric sensing motors, tools for surgeons, or zoomorphic and anthropomorphic soft robots. Some electrochemical characterizations of these soft actuators of artificial muscles have been already reported. In this study, the behaviors of the asymmetric bilayer artificial muscles, PPy-ClO₄/PPy-DBS worked in 0.5 M NaClO₄ aqueous solutions were discussed by the dynamo-voltammetric responses and coulo-dynamic Evolution responses. Especially, the authors are focusing on the thickness ratio between the PPy-ClO₄ and the PPy-DBS layers in this study. In this study, the author investigates the dynamic behavior of the bending actuation of the asymmetric bilayer artificial muscles based on some kinds of the thickness ratio between the anion-driven and the cation-driven layers.

This study focusses on the uniform flow around a rectangular cylinder when a dielectric barrier discharge (DBD) plasma actuator is mounted on the corner of the cylinder. Plasma actuator is driven with a periodic on and off mode (burst modulation). As a result, the drag force acting on the cylinder is reduced when the actuator is driven at around a specific dimensionless burst frequency (St= 0.75). At that time, the Karman vortex shedding is weakened and delayed, and the wake turbulence is reduced.

In order to realize Industry 4.0 and Society 5.0, which create new services and values for social systems, technology that highly integrates the real world and the virtual world is indispensable. However, in the case of equipment for social infrastructure, it is difficult to confirm the actual equipment due to the enormous prototype cost, and simulation using 3D-CAE is also difficult due to the complexity of the product system. Therefore, there are challenges in how to build integrated technology. In this study, we investigated whether the use of 1D-CAE could establish an integrated technology for railways air-conditioner. We also report that the constructed 1D-CAE model is effective for improving the accuracy of failure prediction and estimating the cause of failure.

Lithium-ion batteries are widely used for various applications in mechanical system. Requirements that battery should meet depend on the its application, and have wide variety such as high energy density or high input-output power. To develop a battery, iteration of prototyping and testing is required in each layer of cell, module and system and it takes time. Aiming to shorten development time, we propose system simulator that consists of electrochemical cell model of lithium-ion battery and 1D model of mechanical system. The feature of an electrochemical model is that it uses the design parameter of battery cells, such as electrode composition and thickness, as a variable of model equation. This enables us to predict performance of the cell that installed to the system before cell module and system fabrication, and to reduce lead time. In this paper, we introduce a case of hybrid electric vehicle. The simulation results showed that cell design which enlarges capacity was not the optimal way in the voltage performance when vehicle runs in World-wide harmonized Light duty driving Test Cycles (WLTC).

We designed a process of problem solving or product design in consideration of the functional characteristics of design technologies in recent years. By incorporating tools of systems thinking and Pi-number technique, two loops that feed back validities of hypotheses were established at the upstream of construction of MBD/1DCAE models as the tools for deploying to the organization. The designed process requires machine learning technique to be able to evaluate easiness of learning to evaluate the validities of the hypotheses. If relations of Pi-numbers are obtained in the verification of hypotheses, they can be transformed into explicit expressions for specific parameters, which can be used for the MBD/1DCAE models for deploying to the organization. In the future, we will apply the designed process to products of photographic lenses and verify the designed process.

Recent years, MBD method is used for front-loading of development flow. Especially in the development that requires multi-domain including electronic circuits, the part designed by 3DCAE other than the circuit will be converted into 1DCAE and verified. In 3D verification, there are problems of time and computational resources, but the behavior of the entire system can be verified by raising the level of abstraction of phenomena other than circuits. Conventionally, MBD was mainly verified by mechanical ones, but the importance of verification including electronic parts increased due to the recent change from engine to motor. If the maximum rating value is exceeded for electronic parts, failure and reliability will drop. New consideration is required for electronic parts to satisfy their ratings and reduce their reliability. High-accuracy models of power devices and peripheral parts are necessary to realize this verification. What functions required for models of peripheral components, using a buck switch mode power supply as an example. In the verification of a buck switch mode power supply (SMPS), the inductance model required superposed current characteristics and temperature characteristics. We show that the reliability was secured by the method of creating this inductance model and the SMPS operation verification. -

This study aims to design manufacturing processes with 1DCAE. The efficiency of LEDs rises if LEDs are fabricated with solution growth. However, the comment that what is solution growth is returned when manuscripts about solution growth were submitted. Then, this paper briefs solution growth. A growth process is described with one-dimensional model. The initial state is singular. The similar phenomenon occurs in a thermal conduction phenomenon. An implicit condition is proposed for the purpose of solving the singularity because the phenomenon is nonlinear. The implicit condition is generalized with analysis, abstracting this idea.

Data-driven control ‘V-Tiger’ can design a controller that optimizes settling time and overshoot by using only one experiment data[1]. However, When the performance of the controller as the initial value of the optimization problem is not desired, it may take too much time to solve optimization problem. Therefore, we propose a controller design method that can obtain a desirable response in a short time.

Data-driven control ‘V-Tiger’ can design a controller that optimizes settling time and overshoot by using only one experiment data^[1]. However, when the performance of the controller as the initial value of the optimization problem is not desired, it may take too much time to solve the optimization problem. Therefore, we propose a controller design method that can obtain a desirable response in a short time.

The use of renewable energy sources (REs) such as solar and wind power is necessary to reduce the CO₂ emissions. However, the fluctuating power output of REs renders the electric grid unstable. Gas turbine combined cycle power generation (GTCC) with a rapid start-up and high ramp rate is a potential solution to compensate for the load fluctuation. In this paper, dynamic simulation was conducted to validate the effect of increasing the load change rate on the steam-bottomed cycle of the proposed GTCC and methods to improve operating characteristics at increased load were discussed.

In this paper, concreate recursion process of Model Based Systems Engineering (MBSE) on vehicle engine development was shown. Engine is defined as 3 layers (unit, system, component) in MBSE process. Unit requirements are decomposed to system requirements, the system requirements are decomposed to component requirements. And these are decomposed to hardware spec and software requirement in component layer, finally. However, in some cases, there are few component options because of some restrictions. For these cases, recursion considering component restrictions is needed in order to prevent rework. In proposed method, component restrictions or preconditions such as accuracy or dynamic range are considered in requirement analysis of systems. In addition, component layer proposes key parameters to system layer by sensitivity analysis based on quality engineering in functional analysis. As a result, huge rework back to unit or system redesign caused by undesired component allocation was prevented.

This paper presents an analytical model for cylindrical structures. In actual mechanical structures with cylindrical shapes such as railway vehicle carbodies, the vertical relative displacement between the roof and the floor interacts with lateral displacement of the side panels. To treat this interaction simply, the analytical model proposed in this work introduces curved beams whose bending deformation generate relative axial displacement between both ends of the curved beam according to its bending deformation. Roof, floor and side wall is connected to each other by means of artificial springs provided at both ends of the curved beams. Free vibration analysis and the procedure to derive equation of motion based on the energy principle will be presented in the conference.

This study describes thermal design method of forced convection cooling in high-density packaging electronic equipment using flow and thermal resistance network analysis. Forced convection cooling by the combinations of fans and heat sinks are widely used in lots of electronic equipment. However, in recent high-density packaging electronic equipment, enough clearance which airflow can be generated cannot be prepared and the airflow around the heat sinks becomes complex. In this study, a development of a function model of finned heat sinks mounted in high-density packaging electronic equipment with bypass by using the flow and thermal resistance network analysis. Especially, this paper tried to predict a balance of the supply flow rate between the heat sink and the bypass on the heat sink by obtaining information about pressure drop characteristics of the branch and the confluence around the heat sink.

In this paper, characteristics and feasibility of embossing method was examined for fabrication of metal structures of sub-micrometer size, which is expected to be applied as an optically functional surface. Fine concave structures were machined by FIB on a single crystal diamond tool. Then the diamond tool was pressed on a gold thin film deposited a quartz glass plate, and embossing characteristics were studied. Furthermore, based on comparison with numerical simulations, the relationship between the processing conditions and the embossing height was qualitatively clarified. In addition, a method of etching the embossed thin film to produce a separated fine metal element was examined.

Functional surfaces have been widely used for control of physical and/or chemical properties of substances on the surface. The surface functions have been controlled by coating or the other processes in terms of material treatment so far. Recently, the advanced micro fabrications have also been applied to manufacturing of the functional surfaces. This study presents a fabrication of the micro scale structures on surfaces in millings with end mills having textured edges. In the fabriacation, the end mill is fed back and forth with controlling the spindle axis inclination alternately. The textured edge was finished on a PCD end mill in laser processing with reducing the irradiation diameter on a developed machine. The cutting tests were conducted to verify the presenting fabrication with the end mill, on which the texture shape is formed with a pitch of 10 μm at an apex angle of 90 degrees. The micro asperities were fabricated on surfaces with nealy the same size as the texture one of the edge.

In this study, fine grooves were processed on the surfaces of acrylic resins using a variable-pulse-width-picosecond laser. The near-infrared radiation range objectives for bright-field observation is introduced near the laser beam exit. This objective lens has a high focusing ability. (the beam diameter is approximately 46 μm when using a 5× lens and approximately 2.4 μm when using a 100× lens.) We derived the optimum processing conditions based on the relationships between the surface properties and XY stage scanning speed. As previous studies, we found that the groove shapes can be controlled by adjusting the XY stage scanning speed and duty cycle. The groove shapes were compared and the differences in the fabricated shapes from the previous research were quantitatively shown. The slope of XY stage or the roughness of workpieces before laser processing were evaluated because some groove shapes had low quality. It was suggested that measuring the roughness and waviness of workpieces prior to laser processing and adopting the low-frequency processing conditions could help solve problems during laser processing.

The novel fast atom beam source (FAB) for surface-activated bonding (SAB) method was proposed in order to improve the lifetime of FAB sources. The proposed FAB source achieved the higher efficiency of Ar-FAB irradiation and less wear on the electrodes. This previously study indicated that the applied magnetic fields made the Ar ions converge on the irradiation port, increasing Ar irradiation efficiency. However, it was not measured and not clearly why the proposed FAB source achieved higher performance. In this study, we aim to reveal the factor of achievement high performance and to propose the new structure of the FAB source with much higher performance by plasma analysis. Electrostatic probe studies and the simulation for Ar plasma in the proposed source show that the electron and Ar⁺ density increase near the irradiation port. Moreover, increasing Ar⁺ flux only to the wall with irradiation port indicates improving Ar-FAB irradiation efficiency and suppressing Ar+ sputtering and carbon agglomerates on inside wall of the source.

In this research，we are considering the development of new materials to further improve the performance of materials for connecting rod bearings．The material currently under consideration is a Cu-Ni-Sn alloy．This alloy is excellent in wear resistance，corrosion resistance，and hardness by precipitation．However，the wear resistance when sliding under high load is insufficient．Therefore，Cu-Ni-Sn-S alloys with sulfur，which can be expected as a solid lubricant，are drawing attention．The purpose of this study is to investigate the hardness of Cu-Ni-Sn-S alloy during heat treatment and to investigate the effect of sulfur addition on the surface structure and hardness．As a result，a sufficient hardness of 305.2 HV was obtained after 30-hour aging．Also，segregation of Sn，Ni，and P was observed near the sulfide，which is considered to be due to the addition of sulfur．Based on the sizes of Sn，Ni，and P，it is considered that the effect of adding sulfur on hardness is extremely small．

A new surface modification technique, scanning cyclic press (SCP), was developed. SCP scans a metal surface with a vibrating indenter and refines the surface layer using cyclic compressive loading. This study applied SCP to the surface of magnesium alloy AZ31 under number of cyclic loading of 3.2×10⁵ and 8.0×10⁶ cycles to investigate the effect on surface structure. After applying SCP, the cross sections of specimens were observed by electron back scattering diffraction (EBSD) using SEM. As a result, a fine structure around 1－10 μm in grain size and a twin were formed in the surface layer of both specimens. The depth of these structures from the surface remained unchanged regardless of the number of cyclic loading. However, the surface structure under 8.0×10⁶ cycles was finer than that under 3.2×10⁵ cycles. This is likely caused by the increase of accumulated plastic strain during SCP process.

A new surface modification technique, scanning cyclic press (SCP), was applied to commercially pure titanium (CP-Ti) in a nitrogen atmosphere at room temperature. During the SCP process, a vibrating indenter reciprocally scanned the specimen’s surface to apply cyclic low compressive load. In this study, a possibility of a room-temperature-nitriding technique using SCP was investigated. Before and after SCP, the surface and the cross-section of the specimens were observed using a laser microscope and scanning ion microscope (SIM), respectively. Then, elemental and composition analyses were conducted by using EPMA and XRD. As a result, a pale golden color, which is known as a characteristic of titanium nitride coating, appeared at the surface of SCP-treated specimen. The SIM observation of the cross-section showed that a nanocrystalline structure was created in the surface layer, and the nitrogen element was detected in the same layer. The XRD analysis showed a strong possibility to form titanium nitride at the surface of SCP-treated specimen. These results suggested that nitrogen element surrounding the specimen diffused into the microstructure beneath the surface and likely created titanium nitride during SCP even at room temperature.

Coarse-grained molecular dynamics simulations were performed to compare the adsorption of organic friction modifier (OFM) added in lubricating oil to flat and corrugated surfaces. Stearic acid, dodecane, and hematite were used as the OFM, lubricating oil, and solid surfaces, respectively. The simulation results showed that the increase in the surface number density of adsorbed stearic acid molecules in 100 ns simulations at 353 K was approximately four times faster on the corrugated surface than on the flat surface. We infer that surface roughness may promote adsorption of OFM additives, owing to the enhanced liquid–solid interactions at the corners formed between adjacent layers of solid surfaces.

The surface of silicone rubber composites sheet causes water droplet to be slipped with presence of VGCF (Vapor Growth Carbon Fiber). The availability of sliding property of water droplets like this sheet solves familiar problems such as difficulty in opening doors due to dew condensation in winter. The aim of this research is to develop a surface that water droplets are most slippery by mixing VGCF with silicone rubber. The composites sheet has a tendency that the VGCF does not disperse when the amount of VGCF added exceeds 3wt%. In order to improve this tendency, the effect of combining ultrasonic wave shooting into manufacturing process on the dispersibility was verified, and the dispersibility of VGCF was evaluated numerically. The dispersibility of VGCF can be calculated from deflection of the area ratio of VGCF in cross-sectional image of sheet. With shooting ultrasonic waves, it became possible to produce sheets with clearly dispersed VGCF. In the case of adding 5wt% of VGCF, the composition with shooting ultrasonic wave dispersed 20% more than the one without the ultrasonic wave. Two facts were discovered; the dispersibility was improved as the amount of VGCF was increased and affects the sliding properties of water droplets.

2-Methacryloyloxyethyl phosphorylcholine (MPC) polymer is used as coating material on artificial joint for its hydrated lubricity. In order to elucidate the mechanism of the hydrated lubrication, in this research, we measure the shear viscoelasticity of hydrated MPC polymer films by using a fiber wobbling method (FWM). Simultaneously, we measure the shearing gap by combining microscope underneath the FWM setup and observing the interference fringe. We found that both viscosity and elasticity increased along with the decreasing of gap width. However, the MPC polymer showed a transition from viscous dominant to elastic dominant when the gap is smaller than a certain gap width. This implies that MPC films reduce friction as a low viscos fluid in large shearing gaps and prevent contact between surfaces in small gaps for reducing friction and wear. This may explain the mechanism of hydrated lubrication of MPC film coated on a surface of artificial joint.

This paper presents a novel batch fabrication process of cylindrical skeleton structure with a helical flat-wire-coil spring and insulating parts for tubular shape memory alloy (SMA) active catheter. The fabrication processes based on UV laser lithography and Ni electro-plating on the cylindrical surface was examined on a dummy Cu core rod instead of a tubular SMA actuator. Both 20-μm-thick negative resist (SU-8) micro-structure and positive resist (OFPR-800LB) mold for electroplating were successfully lithographed by UV laser direct drawing with low temperature resist baking process (45℃, 12h). A Ni bias spring with helical flat-wire-coil shape was successfully electroplated in the thick resist mold pattern on a rotationally sputtered Cu seed layer. Mechanical attaching and electric connection parts were also batch fabricated through the fabrication processes.

In this study, we aimed to control the aggregation of SiO₂ nanoparticles generated in a premixed flame and to control the non-aggregated nanoparticles that were generated. By sufficiently diluting hexamethyldisiloxane (HMDSO) with ethanol as a raw liquid material and supplying nitrogen gas to it and bubbling, non-aggregated SiO₂ nanoparticles could be produced. When the mass concentration of HMDSO in the raw material and babbling nitrogen flow rate were 1 wt% and 0.01 SLM, the particle size distribution was bimodal for about 10 nm and about 30 nm because the raw materials contained in the steam respectively could not be constant in the premixed flame. In order to form the almost uniform nanoparticles, it was suggested that it is effective to set the surface growth rate-determining step during particle generation.