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Four months of successfull operations
Dienstag, 19. Januar 2010
- © Martin Herfort, TU Berlin
Beesat has been ejected into it's orbit on September 23rd 2009, four months ago.
It has been contacted on a regular basis by the Beesat team and also already taken it's role in teachings.
Until today no decrease in functionality has been observed and we await many more interesting months with our satellite.
During the past weeks Beesat's angular rates have decreased from more than 50°/s to less than 5°/s. The attached image shows the development of the magnitude of Beesat's angular rate vector measured using our gyros.
The overall trend is clearly reduction of angular rate. The outliers in the image correllate with experiments using reaction wheels. These experiments move the angular rate vector to axes with different moments of inertia and therefore change the magnitude of the angular rate vector.
At current angular rates Beesat's sun- and magnetic field sensors can be evaluated much better, allowing us to incorporate flight results into current developments.
55 days on orbit
Montag, 16. November 2009
Beesat has now been contacted daily by TU Berlin's ground station for the 55 days since it has been launched. Until today we have received a total of 12793 analysable telemetry frames.
Numerous experiments have so far been conducted, including
- analysis of our power system, showing that the satellite generates a little more electric energy than expected
- tests of our magnetic field sensors which work well under space conditions
- tests of the in-house developed sun sensors, showing that they as well work under space conditions
- analysis of thermal behaviour, showing that our surface modifications are suited to raise satellite temperature (see image above) such that especially the batteries are kept within nominal range
Our main payload, the miniaturised reaction wheel system is also beeing tested regularly. The image above shows a standardised curve that has been gathered on-orbit in order to compare the reaction wheels' behaviour on ground and on-orbit.
Work is currently done to transfer our satellite into teachings in order to allow students to gain hands-on experience on satellite operations. The students of this year's satellite operations class will create a completely new ground-station software and telemetry database. They will communicate with Beesat and use their own software to analyse both, offline and online telemetry.
More than 100 orbits
Mittwoch, 30. September 2009
One week after the launch and after more than 100 orbits BEESAT is in excellent conditions. The commissioning phase of the satellite is completed. Now the verification of the newly developed reaction wheels follows.
28 hours on orbit
Donnerstag, 24. September 2009
BEESAT has now been more than 28 hours on its orbit. Telemetry shows that our satellite is alive and healthy.
So far we observed a total of eight passes, one during nighttime, testing the behaviour under different conditions. We have sent numerous commands and received more than 470 telemetry frames.
- Satellite temperatures are as expected,
- Power system is well, batteries are charged in sunlight, last throughout eclipse, power budget is positive
- Switches for various components were tested and perform well
- Measured currents and voltages are within nominal range
- Redundant on-board computer and CAN bus were not needed so far
- Telecommand uplink works well with 4800 bit/s
- Telemetry downlink works well with both 4800 and 9600 bit/s
- Communication can be established from rougly 5° elevation with our GS
QSL reports from radio amateurs
Mittwoch, 23. September 2009
- BEESAT received by radio amateurs.
- © Copyright??
- BEESAT received by radio amateurs.
- © Copyright??
BEESAT's radio signal has been received by radio amateurs.
Marco from italy (IK1ODO) sent us a spectrogram of the second pass at 11:55UTC (upper image), and Mike Ruprecht (DK3WN) has published an image of a BEESAT reception (lower image) on his webpage. Thanks for the support.
First Telemetry received
Mittwoch, 23. September 2009
- Screenshot from 1st. pass of BEESAT
- © Copyright??
During our 1st. pass over Berlin starting roughly 09:30 UTC with a maximum elevation of 7.8° we have received telemetry all throughout the pass.
We have an OBC uptime of more than 10000 seconds, voltages and temperatures are as expected.
YEAH!
BEESAT in orbit
Mittwoch, 23. September 2009
The start went just as planned:
The PSLV lifted-off at 06:21:00 UTC.
BEESAT was separated from the fourth stage at 06:40:31.
The beacon was switched-on at 07:08:00. (436.000 MHz DP0BEE in CW)
As the launch went nominally the preliminary TLEs are valid and we are eagerly awaiting QSL reports:
Skype: beesat_team
Mail: Frank.Baumann(-@-)ILR.TU-Berlin.de
Tel.: 0049-30-314-79464
Request for QSL reports
Dienstag, 22. September 2009
- FM final checkout, © ISRO
- © Copyright??
The rocket will be launched from Satish Dawhan Space Centre in Sriharikota, India at 06:21 UTC (according to last information). The beacon will be switched on at around 07:00 UTC.
Preliminary TLE-Set:
1 99998U 09999Q 09266.27807917 .00000000 00000-0 00000-0 0 00018
2 99998 098.3002 000.8533 0002378 350.5091 222.5822 14.50491512000005
Our beacon will be sent on 436.000 MHz every 40 seconds ("DP0BEE" in CW).
Any reception report to our skype name "beesat_team" or by E-Mail to Martin.Herfort(-at-)ILR.TU-Berlin.de will be greatly appreciated.
Awaiting Launch: Sep 23, 06:21 UTC
Dienstag, 22. September 2009
- PSLV-C14 carrying BEESAT © ISRO
- © Copyright??
After months of waiting we finally have a confirmed launch date:
BEESAT will be launched on an Indian PSLV rocket on Sept. 23 06:21 UTC, 08:21 MESZ.
BEESAT integrated to PSLV
- BEESAT's position on PSLV-C14 ©ISRO
- © ISRO
On September 16th, 2009 the guys from ISIS finished the integration of BEESAT at 02:15 indian standard time. BEESAT now sits on the PSLV and awaits it's launch into orbit.
BEESAT is circled int the image on the right, showing it's position on the 4th stage of the launch vehicle.