Fujio Tsumori

A study is presented of an improved interfacial structure between the electrode and electrolyte of a solid oxide fuel cell. An imprint process, which is considered as a powerful tool to transcribe nano to micropatterns on materials, was employed to imprint fine patterns onto a ceramic sheet of electrolyte. In the presented work, a sheet of ceramic compound material was prepared, and micropatterns were imprinted on its surface. After debinding and sintering, a dense ceramic sheet with fine microp

Abstract In this paper, a biomimetic microstructure related to cilia, which are effective fluidic and conveying systems in nature, is described. Authors have already reported that a magnetic elastomer pillar actuated by a rotating magnetic field can work like a natural cilium. In the present work, we show examples of a cilia array with a metachronal wave as the next step. A metachronal wave is a sequential action of a number of cilia. It is theoretically known that a metachronal wave gives a hig

In this paper, we describe the development of magnetically actuated artificial cilia. Natural cilia are a highly efficient device that produces flow under a small-Reynolds-number state. There are two important characteristics of natural cilia; one is asymmetric movement, which is composed of effective and recovery strokes, and the other is the phase difference of a stroke in each cilium in an array that will produce a metachronal wave. In this paper, we propose an actuation system for artificial

Artificial cilia actuated by an applied magnetic field have been developed. In our previous report, we demonstrated actuated cilia of a few millimeters scale, which were fabricated by cutting a magnetic elastomer sheet. The fabricated artificial cilia worked similarly to natural cilia; however, they had a much larger structure than natural ones, and showed difficulty for use in pumping systems in micro-total analysis systems (µTAS) fields. Thus, our goal is further miniaturization. In this study

Abstract Recently, many studies on bio-mimic soft robots have been reported. Among living organisms, the locomotion of soft-bodied creatures, such as snails, worms and nematodes, have been actively studied. These soft creatures locomote by deforming the muscles of the whole body into waveforms and propagating the waves of the deformation. This locomotion of soft creatures could be applicable to develop a worm-type soft robot, which can move in drain pipes and even in a human body. In this study,

At present, the solid oxide fuel cell (SOFC) is attracting much attention because it possesses the highest power generation efficiency among many types of fuel cell, and SOFC emits only water that does not harm the environment. Recently, the electrolyte structure for SOFC has been processed into various forms to increase the efficiency of SOFC. In this work, we tried to improve the performance of SOFC by changing the mesostructure on the interfaces between the electrolyte and electrodes. This hu

A micro patterning process for thin ceramic sheets is proposed and developed in this paper. Thin sheets with a micro pattern have been expected to improve performance of solid oxide fuel cell. The authors focused on imprinting and powder metallurgy processes, and have developed the combined process, which has been named micro powder imprinting process. In this process, ceramic powder and polymer binder materials are mixed with pure water by milling machine. After drying out the water from the sl

Abstract In this paper, we report on a new system of three-dimensional (3D) printing for a magnetic elastomer that contains magnetic particles. Not only can we fabricate a three-dimensional structure, but we can also control the magnetically anisotropic property of each position in the structure using the present technique. Our new system employed photocurable poly(dimethylsiloxane) (PDMS) as the base material so that a method similar to a conventional 3D printing process with photolithography c

A simulation system for newly developed magnetic micro actuator is proposed and demonstrated in this paper. Magnetic energy and elastic deformation energy are formulated and used to derive deformation of the actuator. The deformation is determined by using the steepest descent method as the total energy is minimized.We prepare two types of actuators to demonstrate reliability of the developed simulation system. Deformation patterns observed here show good agreement with simulated ones. A grid ty

It is important to control the microstructure of powder particles as they could be used to fabricate new functional materials. The deformation of microstructures by the application of magnetic fields is one of the effective methods for controlling microstructures. We attempt to employ magnetic particles and an elastic material to fabricate a new micro device without electric wiring. It is essential to understand how magnetic force works to the micro particle for designing a new micro actuator de

This paper reports a new type magnetic actuator using interaction between micro magnetic elements. Small magnetic elements are arranged periodically on an elastic membrane to actuate a beam structure by an applied magnetic field. The arrangement pattern of elements changed the behavior of the present actuator. Finally we demonstrate a hand type actuator. The thumb of the hand-actuator can be deformed differently from the other four fingers even if the applied magnetic field is homogeneous. It is

Solid oxide fuel cells (SOFCs) are fuel cells made of ceramics. To increase the SOFC energy density, we developed an SOFC with a wavy electrolyte layer. As a wavy electrolyte has a larger reaction surface area than a flat electrolyte, a higher energy density could be obtained. Our proposed process is named micro-powder imprint (µPI) with a multilayer imprint process that is useful for fabricating a microscale pattern on a ceramic sheet such as an SOFC electrolyte layer. µPI is based on nanoimpri

Abstract Pillar arrays have been extensively used in science and engineering, with major applications at the micro or nano scale, requiring a control technique that can operate in a small, confined area. In this study, an active control method for the surface profile was developed using elastic micropillar arrays with magnetic tips. Single-, double-, and multiple-magnetic pillar arrays were fabricated from poly(dimethylsiloxane) and carbonyl iron particles using a mould prepared by laser drillin

Yttria-stabilized zirconia (YSZ) has been used for an electrolyte of solid oxide fuel cells (SOFC). To enhance the efficiency of SOFC, we developed a corrugated, or wavy-shaped, YSZ sheet for the electrolyte. As the corrugated sheet has larger surface area than a flat-type sheet, higher energy density can be obtained. We have proposed micro powder imprint (μPI) with multi-layer imprint process to fabricate micro scale pattern on the both surfaces of a thin YSZ sheet. The μPI is a combined proces

Abstract Soft robotics has become an attractive research topic with the recent development of soft actuators. Herein, we propose a deformable soft actuator with large volumetric changes. The proposed elastomer contains liquid droplets; their transition from the liquid phase to the vapor phase can be controlled by heat. We chose silicone and urethane rubbers as the matrix materials; droplets of water and fluorine were dispersed homogeneously in the rubber matrix as micelles or solutes. After curi