Keiichi Matsuzaki

This paper describes a method of interactive visualization for explaining the behavior of Single Flux Quantum (SFQ) circuits, a kind of logic circuit based on the principle of superconductivity. For the space exploration in the future, there has been an idea to develop devices based on SFQ circuits onboard spacecraft. SFQ circuits are expected to have extremely low power consumption and high computational speed during operation. On the other hand, since the principle of SFQ circuits is greatly different from that of logic circuits of semiconductor devices such as CPUs and memories, visualization tools for understanding such type of circuits are expected to be useful. In this paper we developed an interactive visualization application for SFQ circuits using JavaScript libraries including WebGL-based APIs and discussed issues as well as prospects.

DARTS (http://darts.jaxa.jp/) is a scientific data archive system which provides data of scientific satellites launched by JAXA, and is developed and maintained by Center for Science-satellite Operation and Data Archive (C-SODA) in ISAS/JAXA. We have developed a web interface with search function to provide 2 dimensional image data (all-sky map) obtained from all sky survey observation of infrared astronomy satellite “AKARI”. The all-sky map is composed of many image files which are arranged like as tiles to cover whole celestial sphere and each image occupies a region about several square degrees. This search function is intended to return all image files in the region designated by a user, if they are overlapped with the region. To realize such a search, we adopt a method that each image is divided into a large number of small rectangular areas and then the center of each area is represented by an orthogonal coordinate system to register in the database. This method has the advantages that other external libraries to divide the celestial area such as HEALPix are not needed, and that both celestial poles is not treated as a singular point, and that high-speed search for arbitrary coordinate system can be obtained. To reduce the costs of development and maintenance, we apply the mechanism of AKARI catalogue search to this search function using PHP and PostgreSQL.

GSTOS is Generic Spacecraft Test and Operations Software applied for test and operation system of future ISAS (Institute of Space and Aeronautical Science) spacecraft based on database SIB2 (Spacecraft Information Base version 2). SIB2/GSTOS-1 is a project to provide SIB2/GSTOS for SPRINT-A, ASTRO-H, Bepi/MMO. This paper describes goal, achievement relative to typical test and operation system for former ISAS spacecraft, development status and tasks for the future of SIB2/GSTOS-1.

In order to reduce steps in developments of spacecraft and onboard instruments, we developed two tools SIB2PlanEditor and SIB2Viewer. SIB2PlanEditor is dedicated editor for test procedure described in the ISAS command plan language. SIB2Viewer is a program to enhance capability of user interface for SIB2 (SIB2UI). Both tools reduce simple work in developments and contribute designer of spacecraft and onboard instruments to concentrate on preparation of content of test procedure and design itself. This paper describes function of these tools and evaluated merits through trial usage. By usage of SIB2PlanEditor, time needed for input of test procedure is reduced by factor 1/3~1/2. These tools are also expected to contribute to reduce time of execution of electrical integration and test of the spacecraft through promotion of SIB2 input in earlier stage of the development.

Design of spacecraft and onboard components of ISAS satellites started after the BepiColombo/MMO project are stored in a database called Satellite Information Base Version 2 (SIB2). This database has a complicated data structure and its model itself is under development. In parallel activities, the spacecraft and onboard components must be developed with this model. In the developments of the spacecraft and onboard component, tool which support design with the model, SIB2UI, is needed and should also be developed. On the other hand, the model should be determined with feedback from design of spacecraft and onboard component. In the development of the model of SIB2, shortening of span of the feedback was the most important subject. To resolve the subject, we introduced a technique to implement design tool. This technique consists of a general library xmlExcelHyper which handles a complicated data structure on a spreadsheet program, Microsoft Excel. With this library, developer of design tool can easily implement Excel-based tool which visualizes, imports and exports tree-base data structure which has degree of freedom of selection and repeat.

In order to shorten time span for spacecrafts’ onboard software, we have developed a Model Driven Architecture (MDA) tool named SIB2 generator: integrated development environment for onboard software. To SIB2 generator implemented is not only automatic source code generation but miscellaneous functions which accelerate implementation of application software. We also paid deep attention to enhance adaptability of the automatically generated code into various onboard components. This paper reports development-completion and design rational and results for initial version SIB2 generator.

The Sun continuously expels a huge amount of ionized material into interplanetary space as the solar wind. Despite its influence on the heliospheric environment, the origin of the solar wind has yet to be well identified. In this paper, we report Hinode X-ray Telescope observations of a solar active region. At the edge of the active region, located adjacent to a coronal hole, a pattern of continuous outflow of soft-x-ray-emitting plasmas was identified emanating along apparently open magnetic field lines and into the upper corona. Estimates of temperature and density for the outflowing plasmas suggest a mass loss rate that amounts to approximately 1/4 of the total mass loss rate of the solar wind. These outflows may be indicative of one of the solar wind sources at the Sun.

The solar observation satellite "SOLAR-B," which is being developed under the joint cooperation of JAXA and NAOJ with the U.S.A. (NASA) and the U.K. (PPARC), will be launched in summer 2006. SOLAR-B requires very high pointing stability for its three telescopes. In particular, the Solar Optical Telescope (SOT), which has the highest resolution and narrowest field of view among these telescopes, requires 0.06 [arcsec]_3σ of short-term (10[s]) stability to meet the observation demands. However, it is very difficult to achieve such levels of stability by only using the satellite attitude control system due to disturbance from the observation equipment. Therefore, we propose using the Correlation Tracker and tip-tilt Mirror package (CTM), which stabilizes the sun observation image. CTM consists of a correlation tracker and a piezo-based tip-tilt mirror with servo control electronics. This paper describes the mechanism and the control and determination methods of the control gain of CTM as well as the results of experiments conducted to clarify its capability.