In the field of tissue engineering, it is important to manipulate cells. While either optical or magnetic tweezers method or micro hand is often used in the previous researches, these systems are complicated and difficult to adjust the point of the tools to cells. The challenging point of this paper is to develop a much simpler system with capability of manipulating the cell. By introducing both a high speed vision with micro processor and a micro fluid chip with "Position-Adjustment-Free" channel, manipulating a cell on one dimension in the channel can be easily realized. By using the developed system, we manipulate human red blood cells successively with higher accuracy.

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Much research has focused on producing actively controllable tip catheter for more minimally invasive intravascular treatment. In this work, we designed 4-electrode type active micro catheter using polypyrrole (PPy). We used SEPLEGYDA [○!R]for a seed layer in electrochemical deposition of PPy. SEPLEGYDA[○!R] is low hardness and easy to form a conducting layer compared to metal electrode layer. As a result of a finite element analysis, 4-electrode type active micro catheter achieved the minimum radius of curvature of 16.4mm which is sufficient for intravascular treatment. To realize 4-electrode type active micro catheter, we fabricated unimorph (1-electrode) type active micro catheter to establish a basic fabrication technologies. When a step voltage of 1.0V was applied to the PPy in a NaCl solution, the catheter bent with a radius of curvature of 580mm.

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We have developed a novel multicellular aggregate (spheroid) formation device that utilizes a maskiess grey-scale photolithography. The device was capable of producing hundreds of aggregates rapidly at a time and regulating the diameter of aggregates with complex design. The cellular aggregates have a micro-pore to supply the growth factor and to expel the waste product. As a result, the cellular aggregates (toroidal) enable long-term culture. In addition we can use micro-pore as continuous channel and insert vascular system and nerve system into assembled tissue. These characteristics of the device suggest that it has the potential for use in a wide variety of applications, such as bio actuator, drug screening and tissue engineering.

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We have been developed circulation type blood vessel simulators simulating arteriole network. These simulators have circular cross sections and are achieved by seamless connecting arteriole models and artery models. However, these models have two-point-five-dimension (2.5D), we needed to fabricate three-dimensional (3D) blood vessel simulators for simulating real blood vessel structures with a high degree of accuracy. For this purpose, we propose a novel 3D exposure method as femtosecond laser and mask hybrid exposure: FMEx. FMEx is integrated two-photon absorption exposure by femtosecond laser and conventional photolithography by mask aligner. We report the results of prototyping the circulation type 3D capillary vessel simulator by using FMEx.

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Herein we propose a novel signal encoded 3-D cell culturing scaffold formed of "Surface-functionalized nano-fibrous microcapsules." The proposed scaffold not only provides anchorage for seeded cells but also aims to realize spatial guidance of cell growth and differentiation through chemical release. To demonstrate the feasibility of concept, biodegradable nano-fibrous microcapsules were successfully surface-functionalized with a chemical fluorophore. Next, the surface-functionalized microcapsules were patterned to form a spatially organized scaffold. The results show great potential as a drug releasing scaffold targeted to realize the regeneration of complex functional tissues.

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Microstereolithgraphy was one of the 3D micro fabrication methods to make arbitrary 3d structures. But photo curable polymers using in conventional stereolithography did not have biocompatibility. To overcome this problem, we've already reported that high temperature postbake process gave photo curable polymer cytocompatibility. In this report, stereolithographic objects with transparency and cytocompatibility were accomplished by the high temperature heat process in nitrogen atmosphere. By using MTT assay, almost same cytocompatibility of the postbeked photo curable polymer compared with a commercial cell culture dishes was verified. And our result indicated that cytoxicity of photo curable polymer was reduced due to sublimation and diffusion of cytotoxic substance from cured photo curable polymer. The new post-bake process should be a fundamental technology for future development of biological and medical micromachines.

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Micro/nano robots have been actively studied. Recently, the micro living organisms, especially flagellated bacteria, have been used as the driving forces for the microobjects. To achieve the more precise control of the position of the bacteria-driven microobjects, we previously proposed the method to assemble single bacterium onto the microobject using optical tweezers, unlike the conventional random and mass attachment. The assembly of the single bacterium onto the 3 tm microbead using optical tweezers was experimentally demonstrated. And, it was confirmed that the bacterium was attached on the microbead firmly by observing the movement of the fabricated bacteria-driven microbead. In this paper, we quantitatively evaluate the movements of the bacterium-driven microobject assembled using optical tweezers. The movements of the bacterium-driven microobject and control sample were analyzed using mean square displacement (MSD).

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In this paper, we fabricate and evaluate new probe device which can realize handling of micro objects using thermal gel. In general, probe devices are one of the important devices for micro manipulation. However, conventional probe devices have some problems: damage to the manipulated objects and difficulty to release the handled objects by the surface force. As one solution of these problems, we proposed "soft handling probe". The probe has an electrode and the thermoresponsive polymer can be gelled when a current is applied to the electrode. The assembly of three dimensional structures was demonstrated by the probe. The grasping force by the probe was measured using AFM cantilever. The handling of yeast cell and liposome were also realized by the probe. It is expected that the probe can realize the soft handling by the thermal gel and realize the precise positioning by reducing the effect of surface force.

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The authors aim to develop muscle cell actuators driven by a photostimulation. Recently, bioactuators that exhibit self-organization have been attracting a lot of attention, because biological devices are expected to have significant abilities such as self-reproduction, self-repair, self-assembly. Based on this consideration, we have previously developed a myofilament-actuator, where we have utilized effects of a mechanical stimulation to construct the mechanical structure of such a bio-actuator. More specifically, we found that induction of differentiation into myofilament-like cells from a cultured myoblasts C2C12 is promoted under the mechanical stimulation. Under above circumstances, the next step is to find an appropriate method for driving the bio-actuators. To do so, we introduce channelrhodopsin-2 which works as both a photoreceptor and an ion channel. Based on the above, we cultured muscle cells embedded with the gene of this protein. Then, we observed that the muscle cell actuator is contracted by a blue light stimulation.

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Bio-actuated micro/nano systems using living cells and bacterium have been widely studied to create autonomous micromachines. In this study, we propose a novel type of a micromotor driven by collision of multiple Mycoplasma mobiles. Since the micromotor has asymmetric blades, it can rotate unidirectionally by the net collision of multiple Mycoplasma mobiles. We constructed a simulation software to estimate the rotation of asymmetric rotors. An optimal microrotor which has flower-type blades were fabricated by two-photon microstereolithography. It was demonstrated that the flower-type microrotor could be rotated by random movements of Mycoplasma mobiles.

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This paper reports a novel nanofabrication method for living cell. Our method provided both nano deposition and ablation on a living cell in nanoscale resolution. This paper will show nanostructures fabrication using this electron beam (EB) induced deposition, and will also report cell response for EB direct drawing. Conventional onsite processes for the live cells were reported as laser induced process in micro scale resolution. Our process has nanoscale resolution because of using focused electron beam. We proposed our method for live cell processible nanofabrication to analyze protein scale dynamic reaction on cell system.

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In this study, we proposed a novel three dimensional tissue constructing method using shrinkage of cardiomyocyte gel toward the development of deformable bio-robot. The gel shtinkage effected by cell distribution and its traction force is attributed to nutrient distribution. We forcused on this mechanism and design the nuturient distribution to deform the gel to jellyfish-shaped structure. Finally we succeeded in constructing jellyfish-shaped structure and developing its moving function. Moreover we control the pulsation frequency of the structure with the drag stimulation. Since the velocity of moving has correlation with the pulsation frequency, it is possible to control the moving speed.

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This paper reports the demonstration of a biofuel cell (BFC) with trehalose in insect hemolymph. The analysis result by LC/MS showed that trehalose included in cockroach hemolymph (CHL) was high enough to utilize as a source of power generation. The trehalose BFC was prepared by immobilizing enzymes on electrodes. The maximum power density of 6.07 μW/cm^2 was obtained from cockroach hemolymph added trehalase and mutarotase. Since the open-circuit voltage fell soon due to the adsorption of proteins in the CHL to the surface of the electrodes, the electrodes were protected by a dialysis membrane, which was able to prevent the open-circuit voltage from decreasing by the adsorption and kept it around 300 mV constantly for more than 30 min. Furthermore, the maximum power density was increased to 10.5 μW/cm^2 by using an air electrode. These results show the feasibility of insect power generation based on the electrochemical reactions.

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This paper describes an in-air operable bio-actuator using dorsal vessel (tubular insect heart). The bio-actuators reported so far can work under wet condition i.e. in culture medium since it is necessary to keep cells alive and contracting. To overcome this problem, the bio-actuator was packed into a capsule with culture medium. The beating force of dorsal vessel tissue was measured using a force transducer. Based on the result, the micromanipulator and the capsule were designed and fabricated. The micromanipulator packed into the capsule was taken out from the culture medium after it was confirmed that the dorsal vessel deformed the micromanipulator. Surprisingly, the micromanipulator was deformed in air more vigorously than in the culture medium. The result shows the bio-actuator has applicability to not only wet condition but also in air.

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For the present study, we propose a high frequency on-chip electric knife to fabricate micro-object. High current and voltage input was applied to the edge of electric knife of the order of sub-micron. The local ablation was carried by discharging micro-plasma from the edge of the electric knife. The most of the part of the knife was insulated except a limited region where is controlled by the photolithography technique. This prevents from generating bubbles from micro-electrode when the voltage is applied. We have confirmed the partial ablation of the cell as well as a discharge of plasma in the limited region. Expansion of the current proposed research will contribute to the cell fabrication for to the field of gene engineering and developmental engineering.

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Magneto-Archimedes effect enables label-free cellular manipulation by magnetic force. In the present study, we estimate cell movement using computer simulation and compare with experimental results obtained by image analysis. The magnetic susceptibility of Gd-DTPA was determined using NMR and the force applying on the cell was estimated by magnetic simulation. On the other hand, living cells suspended in culture medium including Gd-DTPA were applied to the magnetic field. As a result, the cells moved to lower area of magnetic flux density and formed an egg-shaped spheroid in the bottom center of the chamber. The estimated moving velocity with the simulation was almost in agreement with the actual one. The results show that the final shape of the aggregated cells can be estimated by the computer simulation.

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This paper reports the first demonstration of a light-regulated bio-micro-actuator powered by a transgenic Drosophila melanogaster DV tissue (Dorsal vessel; insect heart muscle). First, we evaluated the performance of DV tissue to temperature and chemical stimulation. Second, we expressed a mutant form of blue light-sensitive cation channel, channelrhodopsin-2, into the cell membrane of the DV tissue. The DV tissue was assembled into a micro-structure made of poly-dimethylsiloxane (PDMS). The light-sensitive DV tissue contracted synchronously with blue light irradiation, and the micro-actuator was driven in this way. The moving frequency of the micro-actuator increased as irradiation intensity and duration increased. These results demonstrate that the light-driven muscle-powered actuator will have various applications.

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Our previous study has proposed a magnetic levitation in which soft magnetic materials can be suspended by pinning effect of high-temperature superconductors. This paper describes how magnetic materials and magnetic bias affect the levitation performance. It is expected that obtained results may shed further light on the optimal configuration of the levitation system using high-temperature superconductors.

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Since almost all the systems are designed to work at room temperature, these might not work well or stop at very low temperature. Conventional type transport systems work using differential pressures between liquid nitrogen storage tank and room pressure. Thus, centrifugal pump systems able to transport liquid nitrogen by using a superconducting motor are tudied in this paper.

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We propose a miniature spherical motor for 3-DOF axis rotations using iron-gallium alloy (Galfenol). This motor consists of four U shape cores of Galfenol with wound coil for two legs, a permanent magnet, an iron yoke and a spherical rotor sandwiched by the cores. The magnetomotive force of the magnet provides bias magnetostriction for the cores. When currents of same phase flow in coils of two legs (180° phase different in opponent cores), torque for X or Y axis rotation is exerted on the rotor by expansion of one core and contraction of another. On the other hands, 4 cores bend with currents of 180° phase different flow in two legs due to the expansion of one legs and contraction of another, which exerts torque for Z axis rotation. Rotation for X, Y and Z axis is realized by a sawtooth current, such that the rotor rotates with slow expansion and slips at the rapid contraction. We measured the displacements of each cores and verified the principle of 3-DOF rotations.

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The magnetic properties of magnetic material, which are used in cores of magnetic devices, change largely near the Curie temperature. In this paper, magnetic properties at high temperature (near Curie temperature) and low temperature (liquid nitrogen temperature) are examined.

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A lot of space equipment such as the gyroscope, the antenna, the paddle of the solar cell panel, and the reaction wheel need to be driven in multi degrees of freedom. The spherical motor can rotate and positioning the rotor in any direction. Therefore, the spherical motor is suitable for driving such equipment. In this paper, a reaction wheel is picked up from the equipment. Then, discuss the advantages and the problems of the spherical motor for driving the reaction wheel. The specifications of the JAXA planned reaction wheel, CSEM designed reaction sphere, and the AIST developed spherical motor are compared. The AIST developed spherical motor can be applied to the spherical reaction wheel.

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Surface acoustic wave motor has been investigated and then its superior performances such as high speed, high thrust, quick response and so on are demonstrated. In case of application for high temperature environment, piezo material and friction condition will be problems we have to think about. In addition, a small XY stage motor and multi-layered motor structure will fit for some applications.

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An ordinal force-feedback device mainly employs an electromagnetic motor(EMM), and it is excellent in the expression of an elastic feeling. However, it is not easy to express the sense of hardness and roughness. An actuator system(AS) using multilayered piezoelectric actuators has a characteristic which is contrary to AS using EMM. The objective of this study is the development of ideal actuator system for a haptic display. In this paper, a hybrid actuator system combining an EMM with a piezoelectric motor was proposed and examined. As a results, it was confirmed to be able to express hardness and softness by changing the combination of actuators.

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In this paper, we propose a novel rotor embedded disk type multi-degree-of-freedom (MDOF) spherical ultrasonic motor (SUSM). The MDOF-SUSM consists of a spherical rotor and a stator vibrator with all-in-one structure, the spherical rotor is embedded in a stator vibrator with a spherical inner surface, and a motor shaft is mounted on the rotor. The stator vibrator with piezoceramic disks and plates stuck on its surfaces can excite five vibration modes, independently and simultaneously. The spherical rotor of the motor can rotate around three axes by combining two vibration modes among the five vibration modes. This paper describes the basic construction and the operating principle of the rotor embedded type MDOF-SUSM, modal analysis results about the stator vibrator, and some measurement results from the first trial manufacture to verify the operating principle and research the Z-axis rotation. The MDOF-SUSM in this study has possibilities of a simple structure, compact and small size, lightweight, and a large torque-to-weight ratio.

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The purpose of this research is to apply a low-profile ultrasonic motor using sector shaped vibrators for sample spinning of the solid-state nuclear magnetic resonance (NMR) analysis. We have fabricated the motor made of nonmagnetic materials. The transducer consists of two sector shaped vibrators. The maximum diameter of this motor is 17 mm and the height is 41.5 mm. We have evaluated the driving performance of this motor in high magnetic field. As a result, the magnetic field had a small effect on the rotation performance of the motor. Therefore the motor can be used for sample spinning of the solid-state NMR analysis.

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In this study, a small ultrasonic motor which is driven at a cryo temperature has been fabricated and evaluated. The motor consists of a bolt-clamped Langevin-type transducer (BLT), a rotor, a bearing, a spring, and a casing. The maximum diameter and the height of the motor are 22mm and 30.5mm. The ultrasonic motor has been evaluated in the room temperature and in the cryo helium gas. The relationship between contact pre-pressure of the rotor to the BLT the continuously rotating temperature is indicated. The rotation speed was 553 rpm at the room temperature and 65.4 rpm at the 4.5K helium gas.

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The communications tool is developed in the humanoid robot. The equipment development of the technology of miniaturizing technique is demanded because it becomes device arrangement at a position that is higher than center of gravity. Because the above-mentioned problem was solved by using the shape-memory alloy, it reports.

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The patient's load is requested from reduction minimally invasion on a clinical site. This study has aimed at the development of the In-pipe Micro Robot thought that the examination in the blood vessel and the removal of the tumor, etc... As the drive system for the robot, the expansion of the balloon by the force feed of the physiologic saline and the peristalsis movement mechanism using shrinkage were designed and produced. In this study, we developed two type in-pipe micro robots, and examine the effectiveness of these robots experimentally. From several experiments, availability of these robots is confirmed.

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The purpose of this work is to develop a new surface-modification technique for soft mechanisms. We focused on structural color existing natural world. In the previous report, we reported the change of the diffracted light with stretching and fabrication of an FMA(Flexible Microactuator) with diffraction grating structure In this paper, we report a multi grating pattern sheet made from silicone rubber. Multi grating pattern consisting of 9 patterns is used. We fabricated black and transparent rubber sheets with multi grating pattern, which works successfully to change the color with stretching. The experiment shows that the black sheet shows brighter diffracted light than the transparent sheet.

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In recent years, a large number of studies have focused on micro-robots. Moreover, yearly contests have been held in order to develop micro-robot technologies. As a result of these activities, various types of micro-robot have been proposed, including motor-type, piezoelectric-element-type, and electromagnet-type micro-robots. The present study considers a moving mechanism of and a control method for an electromagnet-type micro-robot that can not only run in a straight line but can also turn with only one electromagnet coil using the difference of natural frequencies of the right leg and left leg. In the present paper, the characteristics of the velocity control of the micro-robot running straight on a horizontal plane are investigated through an experiment.

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The goal of this research is to develop adhesive rubber micro structures with micro suction cups, which realize new functions such as flexible-fitting and anisotropic adhesion. They can be applied to various robot mechanisms such as wall-climbing robots and robot hands, etc. Through micro rubber molding methods, we have successfully fabricated the micro structured rubber sheet of 10mm^2 in area, which consists of 144 suction cups of 500μm in diameter. Making the experiments of this sheet, we show experimentally a relationship between the integration of suction cups and flexible-fitting adhesion. Addtionally, the nonsymmetrically-shaped suction cup has been designed using nonlinear finite element method and the model with 10mm in diameter is fabricated. The experimental results show the possibility of this new functional rubber sheet, which can be attached and removed by changing loading direction.

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We propose a new approach for controlling micro robot geometrically constrained in blood vessel pipe, by utilizing magnetic force. The system is composed of four pairs of coil generating magnetic field in the focused area and micro robot made by magnet. The coils produce both driving force and moment for the micro robot. Eventually, the robot moves along the blood pipe depending upon the current for coils. In this report, we explain the mechanism of micro robot and show a couple of experimental results for confirming the idea.

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We proposed a flexible gel actuator with MEMS-based electrodes for forming high electric field in gel. The response time and displacement of actuator is high and large, respectively. This paper shows the improvement of response time using thin plasticized PVC gel actuators by finite element method (FEM). A driving force is assumed proportional to electric filed intensity on this FEM simulation. The response time of the fabricated gel actuators is improved using thin plasticized PVC gel. In the future, we will fabricate gel actuators using MEMS-based electrodes.

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We are developing micro stereolithography technology using two photon absorption. We used electro conductive polymer to build the actuator. In this report, we try to make elector conductive solid object in the protein film as micron order size. Protein film can be useful for support for stereolithography.

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In this study, an optical absolute encoder with a 3-tone reflective scale has been proposed. The 3-tone scale provides more information, compared to conventional absolute scales. Thus, the increase of information density by 3-tone scale contributes to the miniaturization of sensors and rough alignment of the encoder. We have developed a compact sensor and 3-tone reflective scales by MEMS technology. The sensor consists of VCSEL (Vertical-Cavity Surface-Emitting Laser) and PD (Photo Diode) chips. Also, the 3-tone scales have Au total mirrors and Cr half mirrors which are patterned on a glass substrate. With our developed sensor and scales, the applicability of an absolute encoder has been demonstrated. It is expected that this device could be applied to compact absolute encoders for robotics and mechatronics applications.

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This paper presents a MEMS potentiometer that uses a connection through a probe dipping into a μPool (PDP-connection). We proposed a PDP-connection to keep physical restrictions that cause serious problems for micro actuation at a minimum. A PDP-connection employs a probe electrode that is dipped into a μPool filled with a conductive liquid. A PDP-connection works as a variable resistor for a potentiometer as well as low restriction wiring. The proposed potentiometer can drastically reduce the physical restrictions at the contact point of a variable resistor. The developed potentiometer based on the PDP-connection using φ20μm probe could detect displacements of 2 μm with good linearity. The measured restriction force was a few mN at 5 μm/s motion velocity, whereas a commercial potentiometer requires at least 100 mN.

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Detection of the line-of-sight (LOS) has various applications, such as communication technology and welfare field. To realize such applications, there is strong demand for an LOS detection system that does not restrict users' activities and inflicts no mental stress. In this paper, we built pupil position detecting algorithm and demonstrated LOS detection. We confirmed the correlation of the output voltages with respect to the pupil position assuming that a photovoltaic device generates voltage depending on the overlapping area of the device and the pupil. According to the generated voltages of the 2x5 transparent dye-sensitized photovoltaic devices array on eyeglasses, it is successfully detected the eye movement and thus the LOS of the test subject based on the differences in intensities of light reflected from the pupil and the white of the eye. The MEMS-based LOS detection system proposed herein is readily applicable to various promising applications.

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Tactile information is transferred by stimulating finger tactile receptors by the actuators at various spatial and temporal frequencies. When a skin vibration is large displacement and high frequency, tactile receptors can detect effectively. In this paper we propose large displacement MEMS actuator that drives high frequency and produces large displacement for tactile display. The actuator is consisted of a piezoelectric actuator and a hydraulic displacement amplification mechanism (HDAM) that encapsulates a liquid in a micro-chamber with two flexible membranes. HDAM can amplify the piezoelectric actuator's displacement. We investigated Initial Position as a static characteristic. And also owing to HDAM, input amplitude is exactly amplified.

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Photo driven actuators have received an attention in recent years. PLZT has a photostrictive effect and can be driven by non-contact energy supply. In this study, PLZT films have been deposited by using a hydrothermal method. The growth and the condition of crystals would depend on a reactive temperature and an amount of reagent. The depositing condition of PLZT films has been improved and the characteristics of the films have been evaluated. Additionally, PLZT film actuators have been fabricated and those actuators have been driven by the ultraviolet lays. By measuring displacement, electric current and generative force, the PLZT thin film actuators have been evaluated.

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In this research, an ultrasonic vibration mixing device for the hydrothermal deposition system has been designed. A PZT thin film has been deposited on a titanium plate by the hydrothermal method with the fabricated new ultrasonic vibration mixing device. To improve a stir performance, the ultrasonic vibration mixing device has been designed by using the finite element method. The new vibration mechanism has been evaluated. The pressure of 396[kPa] was generated in the autoclave. This value was about twice larger than that of the vibration mechanism of the previous model. The deposited PZT thin film has been observed by the SEM.

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We report the micro fabrication system using Proton Beam Writing for micro chemical chip. The fabrication system utilizes the XY stage control and beam scan base on CAD data. The XY stage control enables this system to spread the fabrication area with centimeter order. Moreover, the method of calculating the scan pattern from general CAD data enables this system to fabricate various shapes. The experimental results demonstrate the centimeter structure which included 121 micro arrays whose diameter is 6 micrometer. This fabrication system using PBW is useful for the micro chemical chip fabrication.

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Polymer actuators are attracting considerable interest due to their special characteristics, including high flexibility and low weight. Ionic polymer-metal composite (IPMC) are polymer actuators that exhibit remarkable bending at driving voltages lower than 2 or 3 V. They have the potential to be used as soft robotic actuators. IPMC consists of a thin ion-exchange membrane with noble metal electrodes formed on both surfaces. Highly durable IPMCs will be fabricated using an electroless chemical plating technique to form metal electrodes. In this research, we have been developed a fabrication method of IPMC with patterned electrode which will be capable of a peristaltic movement. In this paper, we describe a fabrication method for patterning electrodes by the electroless chemical plating technique with SF_6 plasma treatment and the results of performance evaluation of IPMC with SF_6 plasma treatment.

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When a magnetic micro-screw moves in water, it is difficult to go up and to control a magnetic microscrew three-dimensionally because of gravity. Therefore, it is important to control density of a microscrew. Therefore, we have developed magnetically photo-curable (MPC) polymer with hollow microcapsules. This polymer enables us to fabricate a three-dimensional magnetic microstructure whose density is controlled. Since we can control density of this resin, buoyancy of microstructure is able to cancel the effect of gravity. To show neutral buoyancy of the magnetic microscrew, we compared vertical swimming velocity of the microscrew with horizontal velocity. This experimental result shows that vertical velocity coincides with horizontal velocity. This result demonstrates that we have succeeded in fabricating a magnetic microscrew and controlling the microscrew three-dimensionally in water.

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We report on a three-dimensional (3D) molding technique of fabricating bioceramic scaffolds. In this method, ceramic slurry is cast into a 3D polymer master mold, which is fabricated via microstereolithography, by a centrifugal casting method. The polymer master mold is thermally decomposed, so that a complex 3D bioceramic scaffold can be produced. In experiments, the decomposition process of the polymer model was optimized by the master decomposition curve theory to reduce harmful cracks in a green body. As a result, we could produce not only precise lattice models but also sophisticated porous scaffolds using beta-tricalcium phosphate (β-TCP) slurry. This bioceramic 3D molding technique based on microstereolithography will be useful for tailor-made tissue engineering and regeneration medicine.

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This paper presents spatially arranged microelectrodes to allow electrophysiological recordings inside 3D neuronal cultures. Out-of-plane microelectrode probes standing on a substrate have gradation in height. Wire-bonding-based probe technology makes it possible to provide the flexible probes. We would understand the dependent alteration of cellular activities caused by the construction process of 3D artificial neuronal networks, because the developed probes can directly and spatially record cellular activities inside 3D cell cultures. This paper demonstrated electrophysiological activities inside 3D neuronal cultures could be successfully recorded using the embedded probes. Given the results described here, further electrophysiological characterizations of 3D neuronal cultures using our spatially arranged microelectrodes are underway toward bioengineering applications such as: disease models for the study of regeneration and repair of damaged nervous systems, specifically Alzheimer's disease.

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Carbon nanotube (CNT) has potential applications in various fields such as nanosensors. Measurement of thermal property of single CNT in liquid is quite difficult. Here, we propose a novel evaluation model for measurement of the thermal conductivity of single CNT in liquid with a gel sensor impregnated with temperature sensitive quantum dot. Two gel-sensors are fixed to CNT. Heat is input to CNT through the gel sensor. Roles of the gel sensor are temperature sensing and heat input to the CNT by IR laser. Quantum dots are impregnated in this gel sensor. Temperature is measured by detection of fluorescence intensity from the gel sensor. Sensitivity is -1.1 %/K. Accuracy is ±0.5 K. The error of heat input is less than 5%. Thermal conductivity can be calculated from proposed model. The current estimated error of thermal conductivity in this model is 20%.

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In this study, we have developed evanescent-wave-driven micromotors by two-photon microstereolithography. The evanescent-wave-driven micromotor is located on the surface of a high-refractive index substrate attached on a prism. By illuminating a laser beam at an angle greater than the critical angle, evanescent waves are generated under the micromotor. When the laser beam is scattered by the blades of the micromotor, the motor is affected with radiation pressure. As a result, the micromotor can be rotated by evanescent waves. We designed a novel micromotor with grating-like blades by electromagnetic field simulation. In our simulation, the optical torque exerted on the blade is 5 times larger than that of the previous rectangular blade. In addition, we demonstrated that the micromotor with grating-like blades could be rotated 2.5 times faster than the previous micromotor. The evanescent wave micromotors will be applied to optically driven lab-on-a-chip devices.

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In this paper, we proposed cell investigation tool for measurement of physiological conditions of single cell. We also developed new temperature measurement method using temperature dependence of the indicator. The cell investigation tool encapsulates indicators. These tools can be manipulated in a solution by optical tweezers. First, we classified cell investigation tools in four categories. Then, we proposed image analysis of the tools using the color information for temperature measurement. We calibrated the temperature using the tool impregnated with quantum dot by several color information such as HSV, YCrCb. Y and Cr represent the monotone decrease according to the temperature increase, while H and Cb do not represent monotone variation. Measurement value by Cr is stable than the values by Y and V information because the color difference is robust against brightness fluctuation. Therefore, we used Cr information for temperature measurement. Sensitivity is -1.3 %/K and accuracy is 0.3 K.

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Toward design optimization of pneumatic balloon actuators (PBAs), we have performed FEM simulation and demonstrated its applicability to compute and characterize the bending motion of PBAs fabricated from PDMS (polydimethylsiloxane)-based materials. It is shown that typical PBA motions could be successfully captured in the present simulation through the comparison of the computational results obtained in the linearly-elastic region with the actual motions of fabricated devices. It is also indicated that the longitudinally-divided balloon structure presently examined could achieve the bending characteristics with more flexibility compared to the conventional single-balloon structure.

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