Application to buildings of membrane structures in Japan was started from the Osaka Expo'70, including the Air supported structure of the United States of American pavilion A lot of membrane structure was the first big start when it appeared in Japan with the Fujitsu pavilion of the air inflated structure and so on. After that, it follows in research's and development's being started in earnest, and execution issues increase gradually, too, and a membrane structure stands in a line by the steel construction and wooden structure recently, and it has been taking root as a structure system for the large span structure Membrane structures are classified in the Air supported membrane structures, the Suspension membrane structures, the Frame supported membrane structures, and so on The facilities which it is interested many in are built including the Tokyo Dome, and these main buildings are introduced as examples. I believe that these actual applications and the design methods are very useful for application ways to the airship as well and so on.

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This paper describes the operation of the conventional airships. The report consists of 5 phases 1 Background and purposes 2 Operation of conventional airships 3 Research on conventional airships 4 Conclusion and problems In conclusion, the expectation for research and development by the National Aerospace Laboratory and the proposal for research of the Mitaka Research Center of TAO are stated

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A new balloon design concept, named 3-D gore design, has been investigated for the development of a large super-pressure balloon capable of carrying a heavy payload. Each gore of the new balloon has a large circular arc between adjacent load tapes without the help of film elongation. This kind of bulge is obtained by adding excess film not only in circumferential but also in meridional directions and by fixing the side line of the gore to the shorter load tape by a controlled shortening ratio. The film tension is zero in the meridian and extremely small in circumference In addition, the maximum pressure of this balloon does not depend on the balloon volume. According to this concept, the balloon can be designed independent of film extensibility, owing to its uniaxial elongation. A super-pressure balloon designed by this concept was demonstrated successfully through the flight test accomplished in May 1999. This design method will be applicable for not only a large balloon but also for an airship and other large flexible structures made by membrane.

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Space inflatable structures are suitable for constructing lightweight and low-cost large space structures. Therefore, inflatable space structures for reflector antenna and synthetic aperture radar, which are required high surface accuracy, are also being investigated very actively This report describes application of inflatable space structures to membrane antennas. This paper examines planar membrane structures stretched by inflatable torus for membrane antenna structures Fiber reinforced plastics using tnaxial woven fabrics are used for planar membrane structures. Two types of inflatable torus and lightweight planar membrane structures are fabricated for test article Surface accuracy measurements are conducted using the test article. It is clarified that the surface accuracy of the membrane under the various pressure conditions of inflatable torus.

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For further precise investigation of the moon following on SELENE planned for the launch in 2004, exploring the lunar surface is inevitable. This paper describes the critical technologies such as guidance & navigation, obstacle detection, power supply, mobirity system, etc. and has clarified some technical issues for achieving lunar soft landing and exploration. Besides R&D implementation plan including ground test to develop these technologies are discussed. According to the plan the first Japanese soft landing experiment onto the moon is expected to be realized in 2006.

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Engineering Test Satellite-VIII (ETS-VIII) is a geostationary satellite which is scheduled to be launched in 2003 by H-II A launch vehicle^<[1], [2] , [3] , [4]> It is also intended to develop new technology for advanced satellite communications such as mobile communication system with hand-held terminals For this purpose, ETS-VIII is equipped with two Large Deployable Reflectors (LDR) for sending and receiving signals. Figure 1 shows the m-orbit configuration of ETS-VIII. The size of the LDR is 16 7m^* 19.2m in deployed configuration. This reflector is an assembly of 14 independent hexagonal modules composed of deployable truss backup structure and reflector surface The reflector surface is formed by metal mesh and quartz cables, which correct the shape of the surface.The mesh surface of each module is adjusted one by one into parabolic shape and connected using module connecting points on truss backup structure. The locations of connecting points are precisely measured prior to connection.The module connecting points data are installed to SPADE( Simple Partitioning Algorithm based Dynamics of finite Element)model and the surface shape of multi-connected modules in orbit is simulated.This simulations is verified by the measurement result of the surface accuracy of the three connected modules.

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In this paper, we study on-orbit identification algorithm for Multi-Input Multi-Output Large Space Structure(LSS) system which has four RCSs and six atitude angles and rates measurement outputs. In the proposed method, the state-space model is firstly realized by singular value docomposion of Hankel matrices, then, by iterative least square curve fitting process, the modal shape is realized using time response signals. Its ability is confirmed through a numerical study.

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This paper discusses to estimate a modal-parameter method of flexible space structures based on image information. At first, transform metod of the movmg image to 3-D information is described. Then algorithm of ERA(Eigensystem Realization Algorithm) is used for modal frequency and damping coefficent identification. Moreover madal shape vector are estimated by an iterative method from the ERA results. After detailed analytical studies, ground experiment results are shown to demonstrate its capacility.

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Interfacial resonant phenomena of the lowest few modes of a magnetic fluid column supported by a magnetic field are examined experimentally in the presence of gravity. A magnetic fluid column, height 9.78 mm, is formed vertically between Helmholtz like coils fastened on an electrodynamic exciter, and vibrated vertically to produce axisymmetric oscillations. The transitions from standing waves to progressive waves are observed at the resonant ranges, and one-half sub-harmonic oscillations such as the mode (3,1), (4,1) and (5,1) appear at larger forcing amplitudes. The wave mode transitions between these subharmonic waves are also observed. These new phenomena are useful to discuss the liquid column oscillations in a microgravity environment in the Floating Zone Technique.

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A new technique for the measurement of high temperature emissivity is proposed. The method employed here is based on the moving specimen method. The technique is applied to the graphite specimens with several surface roughness conditions. It was observed that the emissibity measured depends on the surface roughness condition and influenced by the time constant of the emissibity sensor.

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Low vapor oil or grease lubricants are useful for longer lifetime of aerospace mechanisms. Oil evaporation loss experiments are conducted with several size of annular gap to examine the effects of effusion characteristics by using high vacuum system. It is useful to design the non-contact seals, labyrinth seals which are applied to inhibit the evaporation loss of lubricants from the mechanical parts. Additionally, differences between the experimental results and calculated results from Knudsen model are discussed.

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The report deal with the realization of pneumatic structure like as "Tokyo Dome" on the Mars or Lunar environment. The first, we brifely summarize the space environment and the structural requirement on the planet or satellite like as the Mars or the Lunar. Also, we discuss the function of the structural material requiring in the space environment. As an example of the structure, we propose a pneumatic structure under the ground of the Mars or the Lunar. Also, we discuss the use of airship on the planet.

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In this paper, active vibration control of flexible structure by high-polymer piezoelectric films, which aims for the realization of smart structures, is investigated. At first, active vibration control method using piezoelectric films as sensor and actuator is discussed and the concept of distributed vibration control method is introduced. Then, several examples which are the author's studies are shown. The topics included are vibration control experiments of cantilever beams using rectangular-shaped sensor/actuator pairs, vibration control experiments of simply supported beams using a triangular sensor/actuator pair, wave absorbing control of cantilever beams using two pairs of triangular sensor/actuator, and vibration control experiments of cantilever beams and circular rings by a self-sensing actuator using piezoelectric films of different thickness. Finally, an overview of this study toward the future is presented.

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Developing a membrane tank was proposed as a method to improve structural weight ratio for launch vehicles. Three structure concepts (Concentric type, Multi type, and Spiral bellow type) were considered. By selecting a combination of type of reusable rocket, fuel to be used, tank placement, and propulsion type utilization, the possibilities of putting the advantages that do not exist in the current metallic tanks into practical use were investigated.

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