The jet pump works by means of tendency of a stream or jet of fluid to drive or carry contiguous particles along with it. In a jet pump the maximum possible realized suction capacity Q₀ will be twice the driving capacity Q₀, because of limitations in area ratio between nozzle and throat. In the case of the newly designed 2-stage jet pump, the suction openings of the 1st and 2nd stage are connected on an even water level. Further, suction water of the 1st stage is also utilized for driving the 2nd stage. One primary objective of designing this trial pump was to achieve Q₃/Q₀=4. Changes in construction design, based on experimentation, were incorporated in the test pump unit on which test results were obtained, as follows : (1) Q₃/Q₀>4 was obtained as anticipated ; further efficiency is favorable. (2) The pump without a diffuser in the first stage outlet showed higher performance than that of a pump having a diffuser. (3) The function of the 1st stage was not influenced by opening or closing the discharge valve. The performance of the pump was, however, affected critically by operation of the suction valve of the 1st stage.

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Previous developed Eel-like robot (prototype 1) has a big head which includes a control device and batteries. So prototype 1 robot meets a lot of resistance on fluid. We developed an Eel-like swimming robot ( ) using elastic Joints with a smaller head. robot has 8 control devices and 8 batteries which are distributed over its body evenly. Eel-like swimming robot has 8 servomotors for actuator joints and 7 phosphor bronze sheet for elastic joints. The control device drives a servomotor individually. The miniaturized head reduced fluid resistance and improved swimming speed of an Eel-like robot. robot swims underwater completely and on the surface of the water.

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周波数7.5MHz,最大径φ3.4mmの細径超音波探触子MINIATURE ULTRASONIC PROBEのPRO-TOTYPE-1および-(オリンパス社・アロカ社製)を使用し,切除胃標本を用いた基礎的検討,ならびに食道,胃,胆道系疾患計10症例を対象とした臨床的検討を行った.PROTOTYPE-1は画像の安定性および解像力の両者において臨床応用するには不十分であったが,PROTO-TYPE-2はラジアル走査式超音波内視鏡GF-UM3(7.5MHz)とほぼ同等の解像力があると考えられ,臨床応用可能と考えられた.MINIATURE ULTRASONIC PROBEの利点は,消化管においては,通常の超音波内視鏡では検索困難な領域(幽門部近傍)や通常の超音波内視鏡通過困難な高度狭窄症例の検索を可能とし,小病変に対しては直視下にPROBEの位置を確認しながら画像描出を行えるという点に存在した.また,胆道領域においては,胆管内腔からの病変部描出にアプローチできるため,超音波診断の新しい展開が期待できた.改良点としては,従来の超音波内視鏡に比べて画像の恒常性が劣ることと超音波ビームの到達深度が浅い事があげられた.なお,病変部に探触子を接触させて画像描出するためには,近距離音場を考慮して,先端バルーンを装着する必要があると考えられた.

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In cardiopulmonary support systems with a membrane oxygenation such as a percutaneous cardiopulmonary support (PCPS) or an extracorporeal membrane oxygenation (ECMO), blood pumps need to generate the pressure rise of approximately 200mmHg or higher, due to the high hydraulic resistances of the membrane oxygenation and of the cannula tubing. In order to realize the blood pump with higher pressure rise, higher anti-hemolysis and thrombosis performances, the development of novel centrifugal blood pump composed of two-stage has been conducted by the authors. In the present paper, effective attempts to decrease the wall shear stress and to suppress the stagnation are introduced for the prevention of hemolysis and thrombosis in blood pumps. The hemolysis test was also carried out and it was clarified that the decrease of wall shear stress is effective as a guideline of design of blood pumps for improving the anti-hemolysis performance.

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著者らはメカニカル走査を利用した実用的なリアルタイム3次元心エコー図法システムを新しく開発した。本システムの3次元映像のフレームレートは毎秒15フレームであり, また3次元プローブのデザインの工夫により経胸壁の肋間音響窓を拡大させることによりシステム全体の基本性能を向上させた。次に臨床例87例において, 僧帽弁を検査対象として本システムの臨床応用のための基礎的検討を行った。僧帽弁のvisualizationおよび僧帽弁の病的形態の診断能力 (diagnosibility) を検討したが, ルーティンの2次元心エコー図の映像画質が良好な患者群において, 心尖部アプローチの場合は優れた僧帽弁の映像性とその病的形態診断能力が示された。しかし, 胸骨傍アプローチの映像画質は心尖部アプローチと比較して劣っており, 本システム全体としてなお改良を必要とすることが認められた。これらの結果から本法が心臓病学の領域で近い将来新しい診断システムとして臨床に応用しうる可能性が示唆された。

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An important aspect which contributes to perception of a product to be of high quality is the consumer′s experience while holding and maneuvering it during its use. The way a product feels in customer′s hand is a very important consideration for a product design these days. Apt examples would be products like Mobile Phone, Camera, and Hair Dryer etc. There are many parameters and considerations which constitute the ultimate feeling of a product while handling it but mass of a product and its distribution could be one of the prime considerations. Unlike functional requirements, it is not possible to quantify the feeling of handling a product which can only be perceived by actually holding the manufactured part. This makes it difficult for the designer to optimize the product for its handling. The aim of the proposed work is to fabricate prototype of the designed product using 3D printing such that it has the same mass and mass distribution as that of the designed product.

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A robotic harvesting system, which emulates the fruit recognition, approach, and picking tasks, has been developed for the purpose of automatic harvesting for eggplants (Solanum melongena L.). In this study the harvesting end-effectors for eggplants (prototype-1 and -) were fabricated. The end-effectors were composed of a fruit-size-judging mechanism, a fruit-grasping mechanism, and a peduncle-cutting mechanism to pick the fruit selectively on the basis of fruit length after the manipulator end closely approaches. An experimental result on picking posture using prototype-1 proved that lifting the fruit at an angle of approximately 30° was effective for separating the fruit from leaves. A basic harvesting experiment using -, which was improved on the fruit-size-judging and fruit-grasping mechanism, was also conducted. It was found that the success rate of harvesting was 62. 5% and the harvesting time per fruit was about 64 seconds. The main cause of unsuccessful harvesting was that the accuracy of detection of the fruit base was not sufficient. This study showed the great feasibility of automating the basic harvesting motion for eggplants.

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In this study, we developed a variable-stiffness and deformable link using shape-memory material and the jamming transition phenomenon. Above its glass transition temperature (T_g), a shape-memory polymer (SMP) can be deformed by applying a small load. SMPs maintain the deformed shape after they have been cooled below T_g, and they return to their original shape when heated above T_g. The reversible change in the elastic modulus between the glassy and rubbery states of SMPs can be on the order of 100–1000 times. We exploited the characteristics of SMPs to develop robot components with variable stiffness and sensitivity. The jamming transition phenomenon for granular material has been widely used as a method to change the stiffness of robots. This phenomenon is the change from fluid-like to solid-like conditions by removing air from a space containing particles. In this study, we developed a variable-stiffness link by combining the SMP and the jamming transition phenomenon. Moreover, by replacing the SMP with shape-memory alloys (SMAs), whose recovery force and elastic modulus are larger than those of SMPs, we prepared a second prototype with variable stiffness. We evaluated the performance of both prototypes, using the SMP or the SMA, with experiments and confirmed the motion principle of the proposed link (e.g., shape recovery and shape fixity). Moreover, it was confirmed that the stiffness of these links can be changed among four states.

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This paper describes the development of a hanger-rope inspection robot for suspension bridges. The inspection robot inspects the hanger rope by going up and down the rope installed vertically downward from the main cable of a suspension bridge. The going-up-and-down mechanism of the robot consists of a drive roller driven by a motor and a non-excitation electromagnetic brake, and the robot can safely descend after climbing the rope at high speed. The developed robot is small in size and light in weight, and an inspection worker can easily install the robot on the rope. In addition, the robot can be wirelessly controlled with ease from the controller. First, this paper describes the hanger-rope inspection strategy of the suspension bridge. Then, the developed

robot is introduced. Next, the result of the hanger-rope inspection in an actual suspension bridge and the problems are clearly revealed by experiment. Finally, the newly developed prototype 3 robot is introduced, and the result of the going-up-and-down experiment is described.

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For a cardiopulmonary support system with a membrane oxygenation such as a percutaneous cardiopulmonary support (PCPS) or an extracorporeal membrane oxygenation (ECMO), a blood pump needs to generate the pressure rise of approximately 200mmHg or higher, due to the high hydraulic resistances of the membrane oxygenation and of the cannula tubing. Using existent single stage rotary pumps with higher pressure rise result in the higher rotational speed of the pumps and possibly lead to the higher amount of hemolysis due to the larger shear stress acting on blood cells. In order to realize a blood pump with higher pressure rise, higher anti-hemolysis and thrombosis performances, the development of novel centrifugal blood pump consisting of two-stage has been conducted by the authors. As the conditions when the hemolysis and thrombosis occur are not clear and the type number of blood pumps is quite small, the design method of blood pumps has not been established yet. In the present paper, effective attempts to decrease the wall shear stress and to suppress the stagnation are introduced for the prevention of hemolysis and thrombosis in blood pumps. The hemolysis test was also carried out and it was clarified that the decrease of wall shear stress is effective as a guideline of design of blood pumps for improving the anti-hemolysis performance.

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This paper describes the performance of a micro vertical-axis wind turbine with variable-pitch straight blades. The proposed variable-pitch angle mechanism has an eccentric point that is different from the main rotational point. One feature of the mechanism is its ability to vary the pitch angle of the blades according to the azimuth angle of the main links, without actuators. The performance of the wind turbine was measured in an open-circuit wind tunnel. The performance of the vertical-axis wind turbine with variable-pitch straight blades was better than one with fixed-pitch blades. A wind turbine with variable-pitch straight blades has wind directivity. It was found that the performance of a wind turbine is dependent upon the blade offset pitch angle, the blade pitch angle amplitude, the size of the turbine, the number of blades, and the airfoil profile.

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ウェブサイトの自動生成する研究が多くあり，その中でも Screen2Code など画像から HTML コードを生成する研究がいくつか存在する。本研究では，最終的な目標である「機械学習を用いたターゲット別のWebデザインの生成及びWebアプリの自動生成に関する研究」を行う上で必要となる生成系AIを用いてデザインツールである Figma で設計したウェブサイトの自動生成を行う手法を提案する。

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To satisfy the miniaturization requirements of semiconductor manufacturing and metrology, orthogonal Z-axis stage controllability of equipment using highly accurate position detectors are necessary in addition to fundamental XY-axes stage movement control. The Z-axis position detector must have high accuracy, high resolution, and high stability against environmental changes in temperature, humidity, and air pressure. In this paper, a two-dimensional encoder based on a grating interferometer detection method is presented. A prototype XZ-axes encoder was built and evaluated for long-term stability against variations in environmental conditions as well as short-range linear accuracy. The evaluation results show that it is feasible to integrate the encoder with a highly accurate two-dimensional (XZ or YZ) stage control with sub-nanometer resolution. The performance of the encoder as a Z-axis position detector satisfies the demands of industry. By applying the methods developed to the third axis, it can be possible to upgrade the position detection system to three dimensions.

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The propulsion method based on the aquatic life has many advantages as compared with the screw propeller. We have been developed Eel-like swimming robots of prototype 1 and . The efficiency of swimming behavior depends on the shape of the robot in the water. In this paper we report the effect of changing the head shape, entire length of Eel-like swimming robot, and the number of the progressive wave. The miniaturized head reduced fluid resistance and improved swimming speed of an Eel-like robot. robot swims underwater completely and on the surface of the water. In the case of swimming by serpentine movement like snakes and eels, furthermore, the swimming efficiency is affected by the shape of the cross section of the body. So we changed it into circular and rectangular cross section, and investigated the effect to the swimming form and the swimming speed. The number of the progressive wave has as big influence on the swimming performances as robot shape.

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In recent years, cordless products have rapidly become popular due to the development of storage battery technology such as lithium-ion batteries. Brushless DC motors (BLDCMs) are widely used to power such products, and higher performance is required. To achieve high performance, it is important to increase the occupancy ratio and to increase the rotation speed. In this study, we examine whether the use of a transverse flux type stator and secondary coil can improve the performance of BLDCMs in order to increase the occupancy ratio and rotational speed.

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In order to help the physical activities of the elderly or physically disabled persons, we propose a new concept of a power-assist inner skeleton robot (i.e., actuated artificial joint) that is supposed to assist the human daily life motion from inside of the human body. This paper presents an implantable 2 degree of freedom (DOF) inner skeleton robot that is designed to assist human elbow flexion-extension motion and forearm supination-pronation motion for daily life activities. We have developed a prototype of the inner skeleton robot that is supposed to assist the motion from inside of the body and act as an actuated artificial joint. The proposed system is controlled based on the activation patterns of the electromyogram (EMG) signals of the user's muscles by applying fuzzy-neuro control method. A joint actuator with angular position sensor is designed for the inner skeleton robot and a T-Mechanism is proposed to keep the bone arrangement similar to the normal human articulation after the elbow arthroplasty. The effectiveness of the proposed system has been evaluated by experiment.

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試作の大腸用2チャンネル電子内視鏡(CF-2T200I)を用いて117例(198病変)に延べ215回の検査または治療を施行し,本スコープの有用性について検討した.施行した215回の内訳は生検を含む通常観察が46回,内視鏡的超音波検査が30回,内視鏡的治療が139回である.本スコープは外径が13.7mmとやや太いが,2チャンネルの鉗子孔(左側2.8mm,右側3.7mm)を有しており,各種の処置具のみならず超音波プローブの挿入も可能である.内視鏡的治療はポリペクトミーが32回(1チャンネル方式:24回,2チャンネル方式:8回),粘膜切除術が107回(1チャンネル方式:81回,2チャンネル方式:26回)であった.2チャンネルを用いることにより適正な位置で病変部を把持・絞扼することが一層容易になり,腺腫や癌などの上皮性病変ばかりでなく,一部の粘膜下腫瘍の完全切除にも有用であった.また,切除直後の出血に対する止血操作も迅速かつ円滑に行えるようになった.以上のごとく,本機種は観察ばかりでなく,超音波検査や切除あるいは止血などの治療における大腸内視鏡としてきわめて有用であると評価しえた.

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