This paper explains a power-assisted chair with a pneumatic-driven moving seat. As a new control technique of the chair, a new motion-sensing concept was introduced into a control system. A basis of the concept is real-time modification to a desired path. The path is transformed by the difference between a standard load pattern and an actual load pattern on a floor. As a result, a function of assist force adjustment is given. This control system was implemented for the power-assisted chair. In addition, a simulation model about the chair, which includes a pneumatic system, physics, and the control, was constructed for verification of the function without human uncertainty. The system has motion-sensing parameters that conduct the behavior of the seat. The function was confirmed by both experiments and simulations. Concerning treatment for humans, the simulations include exploitation of a condition which is peculiar to simulation. At the same time, the effect from values of the parameters was estimated.

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This paper describes the design, fabrication, and evaluation of a dual-purpose component for a micro total analysis system (μTAS). This paper aims to develop a dual-purpose fluid power device achieving two functions, mixing and pumping, with a single structure. By achieving two functions requiring a power source with a single structure, the fluid device can downsize the entire system as a result of high integration. A way to drive fluid is to use ultrasonic vibration of an elastic body, which is used in an ultrasonic motor to drive a solid rotor. In this study, this driving method is applied to drive fluid. That is, fluid is driven by a vibrator arranged as a part of a fluid channel. The vibrator shape is a disk. The vibration modes used are standing vibration of one nodal circle for mixing and traveling vibration of two nodal diameters for pumping. The vibrator is designed by finite element code ANSYS, and is composed of a piezo element (φ20mm × 0.5mm) and a phosphor bronze disk (φ24mm × 0.2mm). A fluid power system using the fabricated vibrator is evaluated for its functions of mixing and pumping. In the case of mixing, the device completely mixed two-layer flow in the measurement area in about 5s. In the case of pumping, the device transports fluid with a flow rate of 150.1μm/s. In addition, the device produces bidirectional and stable flow.

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This study proposes two types of innovative ciliary actuators with a hydrostatic skeleton. Fluid bags work as a flexible ciliary actuator with controlled inner pressure. A one-way motion actuator uses the difference of friction coefficients between two ground contact faces of the fluid bag. A reciprocal motion actuator is composed of one main bag and two sub bags. Both driving principles are confirmed by driving experiments with prototypes. This study also discusses a flexible ciliary actuator sheet that uses the multi layer piping method. To determine the fluid bag shape, stress concentration is analyzed by nonlinear finite element analysis using the software ABAQUS. The optimum fillet radius at the corner is calculated from the analytical result. The manufacturing method of embedded piping is also discussed. In experiment, the prototype actuator sheet moved at 3mm/s with a 12mm cilia length.

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