UWE-3 News

Since launch we received great support from radio amateurs all around the world, which sent us beacon files via e-mail or uploaded them to our ftp-server. More than 6.000 Beacon frames have been collected from the radio amateur community, growing daily.

Beginning next week UWE-3 will not continuously transmit beacons due to transmission tests. We will inform you once the tests are completed.

Today UWE-3 switched to the redundant micro controller as a precautionary measure after 67 days without interruption. At the weekend we had a storm warning for the city of Würzburg, so the antennas have been down for several days.

With the high precision Earth magnetic field measurements of the last weeks we are able to compile a magnetic field map over the orbit tracks after in-orbit-calibration (Fig. 1). This map resembles the reference magnetic field with a precision of better than 2.5% of the magnetic field strength at all points throughout the orbits (Fig. 2).

Today we’re celebrating UWE-3 “three months in space”. Until today we collected about 5 MB of data, tested the OBDH, the efficiency of the power subsystem and the ADCS including the functionality of detumbling and the reaction wheel.

Starting in the last days of January we collected data onboard UWE-3 in high precision mode, mainly from the Earth magnetic field sensors, from the gyroscopes and the power subsystem. Therefore the ADCS sensor suite was constantly turned on causing a continuous total power consumption of around 700–750 mW. The batteries stayed in an expected level between 50–70 % state-of-charge (SOC).

Since the ADCS has been turned on for the first time on Dec. 3rd it has been gathering data showing the tumbling rate of the satellite and its natural decay over several days. Apparent from the data was a natural detumbling rate of about 0.5deg/s per day. The data was recorded in several intervals with different time resolutions between 2 and 65 seconds.