Electro-Conjugate Fluid (ECF) is a kind of dielectric and functional fluid, which produces jet-flow (ECF-jet) by applying high voltage between electrodes. The purpose of this study is the realization of a novel microactuator using an ECF-jet. It is ascertained that a strong ECF-jet is generated under a non-uniform electric field. Therefore, in this paper, a pair of needle-type and ring-type electrodes (a needle-ring electrode pair) are used to obtain a stronger ECF-jet. First, influences of parameters of the needle-ring electrode pair on the pressure due to an ECF-jet are experimentally investigated. Second, a novel microactuator using an ECF-jet with the needle-ring electrode pair is proposed and fabricated, which is driven based on the principle of Bourdon tubes. Finally, the characteristics of the fabricated tube-type ECF microactuator are experimentally investigated.

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Heavy construction machineries are used to rescue and recover natural disasters such as earthquakes or manmade disasters. However in disaster sites, building wrecks, stepped terrain and narrow areas rescue demand, running on rough terrain ability, steering flexibility and structural rigidity. A parallel link steering mechanism is implied in the vehicle that enables them to steer front and rear crawlers. The vehicle can steer 90 degrees to the right and 30 degrees to left, which allows running diagonally and side ways.
A new mechanism has been developed that tilts all four crawlers. It gives the vehicle the ability to run over higher obstacles such as rocks and stairs. In this paper basic features of the vehicle and steering dynamic properties are observed and discussed. Vehicle operational experiments were held to observe the hydraulic characteristic due to the load on hydraulic motors. This field robot could be applied to many fields such as rescue missions, landmine clearance, exploration, agriculture, construction and many other tasks.

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Modern process control valves are often used in combination with positioners that control the main valve stroke corresponding to an input signal. Pneumatic positioners have advantages over electric positioners in an environment where explosive hazards are a concern. However, pneumatic positioners are relatively sensitive to vibration because they have fine moving parts in the pilot stage. A separate-type positioner can solve this problem. It contains long tubing connecting the chamber of the main valve and the pilot stage, so that it is possible to position the pilot stage at a vibration free location. This then gives rise to the question of the magnitude of the transmission lag inherent with long tubing. This paper provides an answer to this question and submits a simulation technique to estimate the dynamics of the separate-type valve positioners.

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