Trans. JSASS Space Tech. Japan Vol. 7, No. ists26, pp. Tf_1-Tf_6, 2009 ISACS-DOC: Monitoring and Diagnostic System for AKARI and HINODE By Mitsue MIZUTANI1), Toshinori HIROSE2), Ryoji TAKAKI3) and Hideyuki HONDA3) 1)Solution Planning Dept., Fujitsu Advanced Solutions Limited, Yokohama Japan; 2)Science Solutions Div., Fujitsu Limited, Chiba Japan; 3)Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Sagamihara Japan (Received May 8th, 2008) ISACS-DOC (Intelligent Satellite Control Software-DOCtor), which is an automatic monitoring and diagnostic system for scientific satellites or spacecraft, aims to rapidly and accurately capture important changes and sign of anomaly during daily satellite operations. After three systems for deep space missions, the new generation of ISACS-DOC with a higher speed processing performance had been developed for the satellites in earth orbit, AKARI and HINODE. This paper reports on the newest ISACS-DOC about enhanced functions, operating status, and an approach to create standards to build and keep up the knowledge data base. Continuous enhancements through the actual operations are the advantage of ISACS-DOC. Key Words: monitoring-and-diagnosing, knowledge-base, satellite, safe-operation, cost-reduction 1. Introduction sample-return probe HAYABUSA (launched in 2003). ISACS-DOC is independent from any other existing In order to satisfy the high-grade observation satellite operation systems and has high flexibility to add requirements of a scientific satellite, the onboard and new functions and monitoring methods, so it acts as a ground operation systems are becoming more complicated pilot system to improve satellite operation systems. The and elaborate. For this reason there is a real need to monitoring and diagnostic techniques verified by this ensure accurate and safe satellite operations. Since 1992 system will contribute to the continuous improvement of Institute of Space and Astronautical Science of Japan satellite operational technologies through their Aerospace Exploration Agency (ISAS/JAXA) has been incorporation into future satellite control systems. conducting research and development on a ground system The next-generation of ISACS-DOC with a higher for monitoring and diagnosing the status of satellites. At processing performance has been developed (4) and put the beginning of the research and development of the into operation for AKARI (ASTRO-F) since it launched in system, no similar systems which diagnose a whole 2006. Infrared Imaging Surveyor AKARI is in a satellite in practical use could be found in Japan and any low-altitude earth orbit and different in various aspects other countries. This system is called Intelligent Satellite from the deep space probes targeted by the past Control Software-DOCtor (ISACS-DOC) (1, 2, 3). ISACS-DOC systems. The greatest difference in terms of The purposes of ISACS-DOC are to accurately grasp ISACS-DOC for AKARI is the requirement for signs of serious change and abnormality of any onboard high-speed data processing. The short visible time (deep system during regular operation without the need of space spacecraft HAYABUSA: 8 hours, AKARI: 10 experts in the satellite control room, to issue an alert on a min/path and 4 paths/day) and high-rate downlink data display or send out an e-mail, to enhance the safety of transfer (HAYABUSA: 16 Kbps, AKARI: 4 Mbps) means satellite operations, and consequently to reduce that a large volume of data needs to be processed in a operational costs. ISACS-DOC can be positioned as a short period of time. Moreover, it is preferable to process system which supports monitoring by an operator in both real and reproduced telemetry data at the same time. regular operation and diagnosis by an expert in abnormal For high-speed data processing, the processing operation. If the cause of an incident or irregularity can be performance of ISACS-DOC for AKARI is enhanced by identified with a high degree of reliability, the system conducting optimization of data processing procedures. should serve up diagnostic results and solutions. However, The newest ISACS-DOC has been developed for if the cause cannot be identified from detected signs, it is HINODE (SOLAR-B) based on the system for AKARI. preferable to consult an expert, presenting the related Solar Observatory HINODE is also in a low-altitude earth information. ISACS-DOC should help the expert to orbit and its requirements for monitoring and diagnostic diagnose the incident or abnormality. To do so, the are similar to AKARI. information from both the satellite and ground facilities Both of ISACS-DOCs for AKARI and HINODE needs to be integrated and presented. continue to operate successfully. So far, ISACS-DOC system has been applied to the This paper reports on the enhanced functions, operating following deep space missions - the Geomagnetic status, and an approach to create standards to build and Observation Satellite GEOTAIL (launched in 1992), Mars keep up the knowledge data base of the monitoring and Explorer NOZOMI (launched in 1998), and a diagnostic system ISACS-DOC. Copyright© 2009 by the Japan Society for Aeronautical and Space Sciences and ISTS. All rights reserved. Tf_1 Trans. JSASS Space Tech. Japan Vol. 7, No. ists26 (2009) Figure 1: Operation image of ISACS-DOC for satellites in earth orbit 2. Overview of ISACS-DOC Figure 2 shows the main window of ISACS-DOC. 2.1. Outline of ISACS-DOC Detected anomalies are listed in the main part of the Figure 1 shows an operation image of ISACS-DOCs for window, which is the most important region for AKARI and HINODE which are satellites in earth orbit. ISACS-DOC users. Each detected anomaly is linked to its ISACS-DOC system receives both real time and monitor window (Fig. 3), so that the users can grasp the reproduced telemetry data from the data distribution current status of the anomaly. server, and monitors and diagnoses them. The diagnosed results are sent by e-mail and referable though web browser display. ISACS-DOC consists of following 6 main functions. 1. Import: the system imports knowledge data base and telemetry definition data base, and extracts telemetry entry, which are required in monitoring and diagnosing. 2. Telemetry reception: the system receives telemetry data in real time, decomposes them to each telemetry entry, extracts status values, converts to physical Figure 2: Main window of ISACS-DOC values and finally creates primary data, according to the telemetry definition data base. 3. Monitoring data creation: the system creates monitoring data which are necessary for monitoring and diagnosing, based on the knowledge data base. A filtering procedure and limit check are applied to primary data, creating secondary data. Compound data are created from multiple data: secondary data and compound data, as needed. 4. Monitoring and diagnosing: the system monitors and diagnoses according to the definition of knowledge data base. 5. Display: monitored and diagnosed results are shown through a HTTP server. 6. Notification by e-mail: monitored and diagnosed results are sent by e-mail after the spacecraft operation or monitoring and diagnosing of reproduced telemetry Figure 3: Monitor window with detailed information data are completed. Tf_2 M. MIZUTANI et al.: ISACS-DOC: Monitoring and Diagnostic System for AKARI and HINODE The monitor window (Fig. 3) shows detailed 3.1. System improvement information: 1) current values of the anomaly data, 2) The following functions were enhanced in the body of conditions of anomaly detection, 3) setting values of limit ISACS-DOC. checks, 4) time series plots of not only the anomaly data a) E-mail sortation but also the related data, which provides valuable clues The purpose of the e-mail sortation is to serve and for an understanding of the circumstances, and 5) direct the alert e-mails to the appropriate persons. messages of anomaly descriptions and the way to ISACS-DOC notifies monitored and diagnosed results response. by e-mail. As the e-mail is made after the series of On the left side of the main window (Fig. 2), there is a telemetry data form the spacecraft real time operation or list menu for all monitoring items, which show current the data reproduced and downloaded operation are status of monitoring data regardless of whether an completed, the monitored and diagnosed results contain anomaly is detected. Each listed monitoring item is linked some monitoring alert items in a variety of subsystems (if to its monitor window (Fig. 3). any). The function of e-mail sortation filters the results, edits the alert e-mail by the kind of subsystems, then 2.2. Knowledge data base serves and directs the e-mails to the appropriate persons. Diagnostic requirements are defined in the knowledge b) Watchdog of ISACS-DOC itself data base. The data used for diagnosis and detecting the The purpose of the watchdog of ISACS-DOC is to early signs or anomaly are described on mainly these three monitor ISACS-DOC system itself and notify the kinds of spreadsheets, as follows. administrator of ISACS-DOC by e-mail of operation status of ISACS- DOC system. 1. Diagnostic input data (status and analog data): the ISACS-DOC system works with those three processes, input data which are necessary for monitoring and the monitoring process (real time), the monitoring process diagnosis are defined in these status and analog data (reproduced), and the monitoring control process. The sheets. For example, the telemetry name, the limit function of the watchdog of ISACS-DOC checks itself values for limit check, the collecting cycle and period every 30 minutes whether those processes are alive or not, of the data, the filtering type and valid/invalid and if an ISACS-DOC system error should be found, conditions. sends DOC-error e-mail every 30 minutes. If no 2. Compound data: the new data which are created with ISACS-DOC system error is found, it sends DOC-alive input data or other compound data in ISACS-DOC are e-mail once a day.