Odin During Year Six, Implementing Additional Autonomy In-Orbit

The aeronomy and astronomy scientific mission Odin, a Swedish led project in cooperation with Canada, Finland and France, was designed for a lifetime of two years. The satellite carries a tuneable submm radiometer working at 500 GHz complemented with a spectrograph covering both optical and infrared wavelengths. Although the satellite already at start was capable of autonomous operations during the full orbit and for several days, it soon after launch in February 2001 became apparent that both the GPS receiver and the cryogenic cooler demanded much more operator intervention than planned for. From a rather man-intensive operation scenario with commands transmitted to the satellite eight to ten times a day, the Swedish Space Corporation, SSC, gradually improved the system and liberated the operator on duty. Today, for cost reasons and due to custom demands, SSC is ready to automate much of the regular operations and control the 250 kg spacecraft on a working hour basis only. A prerequisite to this step is that the attitude control system is tuned to a very high level, that the power system is well tested and that the data communicati on so far never has produced a severe anomaly. After mid April 2006, after more than 5 years in-orbit, the satellite is believed very well known with clear signatures on most situations. It still carries full redundancy and new anomalies are rare. These facts, together with some minor adjustment in the scientific schedule, open-up for a more autonomous mission with corrective actions automatically triggered from the control centre on the most common problem signatures. The system will be tested and verified during the summer of 2006.