We have many small diameter pipes that are gas or water pipes for individual or corporate houses and boilers or hot water pipes for industries. They must be periodically inspected in order to protect the accident previously. Diameters of these pipes are different at the place where pipes change from the main to the branch and a step comes here. The inspection robot for these pipes must move different diameter and go over the step. We propose a mobile robot that imitates the moving of a green caterpillar. The robot is constructed by the eight parallel rubber bellows and three suction brakes. The fabricated mobile robot was confirmed to move in different diameter pipes whose diameters are more than 70 mm. Its speed was 20 mm/s.

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In this paper, a novel pneumatic cylinder is proposed, named Magnetic Brake Cylinder. It is composed of a tank, a pneumatic cylinder, and a permanent magnet, and with this, the piston is held by the attractive force of the magnet until the pressure inside the tank is very high, offering a higher driving power than an ordinary cylinder when using the same pressure source. In addition, a control method of its driving power is introduced. The developed actuator is then mounted into two types of rescue inspectors: a rolling and jumping rescue robot, which uses a cylinder to jump over obstacles, and a throw and collect rescue inspector, which deploys with the cylinder a child machine over high obstacles. Both developed prototypes showed higher jumping and throwing height than when using an ordinary cylinder, proving to be an option of effective enhancement of traversing ability for pneumatically powered robots.

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We have developed an artificial finger which have human tactile sensibility function, such as be desired for some kind of robots. This finger can recognizes some materials pressing and tracing object with the arm actuated by the pneumatic cylinder. There are many factors in recognizing what touched material was. The recognition of materials is run by the neural network system which can be usefully to obscure and complicated control. The sensor in the finger has been used a piezo-electric element and a strain gauge with a thermo-couple respectively before. However only one of these sensors can be installed for one finger and the two or more fingers must be used to recognize one object. Then, the complete recognition is difficult for the reduction of measurement accuracy caused by individual try of many finger and the problem of the setting of output data in the neural network system. Therefore, the purpose in this report is to unify two or more sensors into one finger, and to fulfill the human tactile sensibility function more similar to human than previous subj ect. In this report, the improvement of the sensor and the device of the neural network are shown.

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The purpose of our study is to develop “Walking Assisting System” that assists the aged and alternative people to walk by themselves, and that can be used as a welfare system to take care of them. Since this system moves by compressed air, no harmful substances are used, and it can apply power as flexibly as human muscles do. Additionally, even in any unexpected situations, the shock and burden to the person using the system are kept to the minimum.
This system not only supports walking on level ground but also assists the movement of the knee joint in walking up and down the stairs, by sensing and acknowledging the walking place of the user and sending compressed air into the pneumatic cylinder at the appropriate timing. In this study, we have installed the acceleration sensors instead of previous inclination sensors, and collected walking data from a wide variety of people with different body sizes and walking speed. Then, we have pursued a control system which can distinguish and assist steady walking in any condition, by generalizing the unique personal factors of various people and determining the discrimination conditions for each of them.

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A flow visualization of a liquid crystal was conducted under the application of an electric field in a mini cylinder with electrode strips on the inner surface. Three-phase alternating currents were used as rotation electric fields to generate the rotational flow of the liquid crystal. A pump with a spiral flow channel was designed based on the rotational flow mechanism of the liquid crystal by using the three-phase alternating currents. The pressure-flow rate characteristics of the pump were measured and the characteristics for the length and the shape of the flow channel in the pump were investigated for various amplitudes of electric fields. The pressure increased when we used a liquid crystal with a high dielectric constant and a high kinematic viscosity for the constant voltage. Dimensional analysis was conducted to arrange the characteristics of the present pump simply and the non-dimensional flow rate and pressure were almost on one line. The size of our pump can be decreased by further research. This study contributes to the development of amicro-pump in micro-fabricated systems and our pump eliminates mechanical vibration and noise.

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The paper proposes and develops a novel smart ER microactuator with inherent position feedback mechanism. The microactuator consists of a pair of movable and fixed parallel plate electrodes with variable gap length and an upstream restrictor, and ERF (electro-rheological fluid) is supplied as a working fluid. By applying voltage to the electrodes, with the increased pressure drop due to ERF viscosity increase, the electrode gap length i.e. the output displacement increases. Also the microactuator can suppress the displacement due to external force by the inherent position feedback mechanism. The mechanism utilizes increase of the flow resistance between the electrodes for decrease of the electrode gap length. In this paper, the structure and working principle are revealed and the mathematical model is derived. Then, a microactuator is fabricated and the characteristics are experimentally clarified. Furthermore, a mechanism to magnify the output displacement is proposed and the validity is confirmed through experiments.

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We proposed an amorphous compound fluid (ACF) as a new intelligent or smart fluid. This fluid contains nm-size magnetite and 1μm-sized amorphous particles in a solvent. This report shows, first, experimental data regarding the viscosity of ACF in a cone-type rotating rheometer under a transverse magnetic field and its magnetization under a DC magnetic field. The experimental results are then compared with those for previous magnetic responsive fluids, magnetic compound fluid (MCF), magneto-rheological fluid (MRF), and magnetic fluid (MF). Those magnetic clusters as aggregated particles were investigated by optical observation. Finally, this report shows the experimental results of engineering applications on polishing that utilize the ACF, and compares the results with polishing that utilizes MCF.

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Agricultural vehicle manufacturers are employing new semi-active cab suspensions using Magnetorheological (MR) technology. The use of MR technology in cab suspensions is a logical next step in improving operator safety and comfort. The speed and simplicity of MR technology enables the use of low-stiffness springs without the compromise between ride and stability, and can provide roll, isolation and pitch stability. MR fluids are materials that respond to a magnetic field with a dramatic change in rheological behavior. These fluids can reversibly change instantaneously from a free-flowing liquid to a semi-solid with controllable yield strength when exposed to a magnetic field. MR systemshave been developed with a modular, integrated approach that can include a damper containing MR fluid, air spring, automatic electronic leveling, sensors, controller, and CANbus data communication.

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