19 November 2009
First image from the Horizon Sensor
17 November 2009
First high-resolution images
The first officially released image will be sent to the Department of Science and Technology when available. The Department may publish the particular image at its own convenience. Further images on this blog will be published with the consent of the Department.
08 November 2009
SA-AMSAT payload activation over the USA
Shown below is the satellite footprint over the USA for the 14:18 UTC pass (left) and 15:52 pass (right).
From what I could decypher from the recordings, the following callsigns were heard (callsigns from the 14:18 pass are shown in yellow and those from the 15:52 pass in red):
06 November 2009
Data transmitter activated
The image below shows the captured test pattern.
Fine Sun Sensor calibrated
05 November 2009
Three-axis stabilized
03 November 2009
SA-AMSAT payload status
During the commissioning of Sumbandila we try to work in the scheduling of the SA-AMSAT payload as often as we can, but the service can by no means be guaranteed at this stage. The commissioning of the satellite is expected to last more or less six months (from date of launch), during which time our primary focus is on demonstrating success with the high-resolution imager - the main payload on the satellite.
The activation schedule for the SA-AMSAT payload will be published on the AMSAT-BB, in addition to being visible on the Google Group, as and when our satellite commissioning schedule permits activation.
We appreciate the eager participation of all Hams worldwide, and would like to encourage making your feedback visible on the Google Group.
ADCS code updated
In addition, we continued with periodic scheduling of the SA-AMSAT payload and recently had contacts through the satellite from the USA and Australia.
We are now working towards obtaining the first high-resolution images from the on-board linescan and matrix detectors.
24 October 2009
Fine Sun Sensor image
Below is a graph depicting the extracted X and Y coordinates of the centroid, calculated 1s apart, for a duration of 1 hour and 4 minutes (total sunlit part of one complete orbit).
21 October 2009
OSCAR number (SO-67) allocated to Sumbandila
You can also listen to an edited version of the latest ARNewsline report here (see www.arnewsline.org for more detail).
I am in receipt of an e-mail sent to the AMSAT-NA Board of Directors by Hans van de Groenendaal, Secretary SA AMSAT.
19 October 2009
SA AMSAT payload tested successfully
Feedback from some of the Hams that participated in the first test:
- Congratulations to all part of the success of the first Sumbandilasat comms. Well done! (Eddie Leighton, ZS6BNE)
- When I was on freq the Sat's audio was clear with a S7 signal which sounds just like a local repeater. Congrats to the TEAM ! (Andre van Deventer, ZS2BK)
- The down link was pretty strong - It's at least 10dB stronger than AO51/SO50 given the same setup. Good news indeed. Suggest operation from Quadrifilar Omni with a low noise preamp on 70cm might be quite achievable (Allan Saul, ZS1LS)
17 October 2009
First month in space
13 October 2009
First video received from the satellite
12 October 2009
Effects of radiation
03 October 2009
Satellite Nadir pointing
30 September 2009
New software for ADCS processor
- New coefficients for the 2009 IGRF model
- Latest NORAD elements
- Calibration values for the fluxgate magnetometer
- Minor modifications to code functionality
The OBC is running more reliably after modifying some EDAC parameters. We have identified a couple of improvements to the flight code which will be uploaded soon. This will affect only some of the software modules running on the QNX operating system, so that we do not have to upload and replace all the flight software.
26 September 2009
Whole Orbit Data (WOD) collected
24 September 2009
Sumbandila Two-Line-Element (TLE) set
After correcting the TLE information, our communication with the satellite is more consistent and reliable.
We intend to affect the improvements that we made to our ground station equipment, to the SAC ground station in the coming week.
22 September 2009
Sumbandilasat Technical Status Report No. 1
The two autonomous Attitude Determination and Control System (ADCS) controllers (Bdot and Y-Thompson; Bdot-Sun) running on a small micro processor on the magnetic subsystem (no floating point processing) are perfectly pitching the satellite at 2°/sec with the main body-mount solar panel facing the sun. The power system is therefore running optimally. We are satisfied with the thermal state of the satellite in the current basic attitude control mode.
As expected, the 500km orbit of the satellite causes incidences of short contact opportunities with the satellite due to the fact that our ground station is located at the Engineering Faculty (in Stellenbosch) where it is surrounded by various high mountains. We have identified certain aspects in our communication setup on the ground which can be improved to make the communications with the satellite more robust and reliable.
In addition, we are re-evaluating the possibility to extend the contact time with the satellite by also employing the Sumbandilasat TT&C ground station at SAC (Hartebeeshoek), by remotely controlling passes from Stellenbosch.
At the moment we are focusing on the commissioning of the main On-Board Computer that will allow us to collect whole-orbit telemetry data, calibrate the magnetometer and proceed to the more advanced ADCS control modes on the main Attitude Computer.
17/09/2009 20:48 Our first pass
We are extremely pleased with our baby in space!! Our first pass last night at 20:48 local time was a very low elevation Eastern pass with some mountains obscuring the “view” as well, but the satellite responded beautifully almost immediately after sending the first command from the Stellenbosch ground station!
We received real-time telemetry which suggested that the satellite was already executing an autonomous attitude stabilization maneuver. This was confirmed during the second pass where we also had good communications. This morning the satellite was stable in a sun-Thompson mode.
18 September 2009
Estimated angular rates
The graph below shows the estimated angular rates 2 hours after launcher separation, already close to Y-Thompson spin at -2 deg/sec. The Y and Z angular rates are less than 0.5 deg/sec.
Current Keplerian Elements
Last Update: 1 Febr 2010
Element set: 404
Sumbandila 1 35870U 09049F 10032.48635300 .00000433 00000-0 21444-4 0 4040 2 35870 097.3525 084.8560 0011505 166.1189 300.7196 15.22856092 20818