Canard based controller using an adaptive notch filter is proposed to control the attitude of launch vehicles including the ISAS's sounding rocket `S-520'. As the characteristics of launch vehicles are time variant in nature, conventional time invariant controller is not suitable for this purpose. Here, adaptive notch filter is proposed to treat the time variant nature. This adaptive filter acts to null out the structural bending mode, which often causes the instability of the attitude controller. The proposed adaptation law requires only limited calculation cost. It means that it is easy to install to the real flight system. The hardware module which aims to control the attitude of the sounding rocket `S-520' is designed and verified not only by the numerical simulations, but also by the hardware tests.

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There is increasing demand for constructing large structures in space due to the continued increase in space utilization. Space inflatable structures make it possible to construct large space structures that do not need complex deployment mechanisms or mechanical actuators. Rigidizing a space inflatable structure after inflation allows it to resist warping due to temperature variation and damage caused by space debris and meteoroids. Rigidizable space inflatable structures must have long shelf-life and excellent foldability. This paper proposes a rigidizing membrane that uses co-woven fabrics: fibrous thermoplastics (the matrix resin) are interwoven with glass fiber (the reinforcement material). The rigidizing conditions are clarified by experiments that place membrane specimens in a furnace. The membrane construction method is evaluated by a rigidization experiment involving a inflatable cylindrical structure. The validity of the cool rigidization method using thermally plasticizing co-woven fabrics is clarified through these evaluations.

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The next generation of geo-stationary mobile communication satellites will, most likely, use large flexible planar antennas. For this reason there is a strong interest in using very thin, membrane type planar surfaces together with inflatable support structures for such antennas. Unfortunately, existing membrane materials would yield excessively heavy antennas. This paper proposes the use of a mesh-type membrane based on a triaxial woven fabric using PBO (poly-p-phenylene benzobisoxazole) fibers to realize extremely lightweight antennas. A circular test membrane which diameter is 1.5 m is constructed and assessed to be mounted on an inflatable torus. Triaxial woven fabrics reinforced with plastic are used as the planar membrane structures. Two types of inflatable torus and the planar membrane structures are fabricated, and their surface accuracy is measured. The results of this study show that the surface accuracy of the membrane is clarified under the various pressure conditions of the inflatable torus and that the proposed membrane can be used for planar antenna structures.

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The H-2A launch vehicle launched August 29,2001 is well balanced in payload capability, reliability, practicality, safety, and cost compared to be H-2 launch vehicle. To realize these concepts, aggressive efforts to make a less costly, less risky launch vehicle have transformed the H-2 into an almost completely new booster. We describe new H-2A technologies and its maiden flight results.

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In order to study dynamic response and establish control logic of supersonic air breathing engine, restart control tests of subscale engine model, that consists of axisymmetric intake and turbojet engine are done at ISAS supersonic wind tunnel (Mach 3). Assuming the condition that the combustion flame is blown out by the unstart, restart control sequences are set as follows. First, after a wind tunnel is started, the core engine is ignited. Second, the intake is restarted while the core engine is controlled. Third, the intake spike position and the terminal shock position are controlled and intake total pressure recovery becomes the designed value (60%). Tests are successful and the engine thrust is recovered for approximately 30-40 seconds after the intake unstart. Sudden increase of combustor flame temperature and rotational speed after the intake unstart is shown experimentally. This phenomenon is inevitable for supersonic engines that apply turbojet cycle as a core engine. To reduce sudden increase of the flame temperature, new sequence to close a fuel control valve after detection of the intake unstart is done and an increase of the flame temperature is reduced. Furthermore, necessity of avoidance of the intake buzz is shown experimentally. To avoid the intake buzz, buzz margin control by the bypass door is proposed and succeeded.

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