SEEDS-II (Space Engineering Education Satellite II) is the successor of our first satellite SEEDS. SEEDS-II is also a CubeSat with 10cm cubic and 1kg in weight. The summary of SEEDS-II is shown in the table below. The official name is SEEDS-II, but we call it "SEEDS" because the launch of the first one was failed and it is our first satellite that reached in space.
budget supplied by our university, and Grant by MEXT (Good Practice program)
SEEDS-II was developed on the basis of the design conept such that the subsystem FMR receiving the uplink command and performing the flight management manages the whole of the satellite system, which is the same as SEEDS. SEEDS-II is improved from SEEDS in the following points:
Change of solar cells (from Si type to Gs type), and installation of shunt circuit to consume the surplus power caused by the improvement of the power generation efficiency.
Change of the solar cell boards and the position of the data port caused by the change of solar cells
Change of telemetry format of CW
Expansion of function of characeter packet transmission (from 16 characters to 120 characters including Japanese characeter)
Expansion of function of digi-talker (from english voice 60 seconds to english boice, SSTV signal, Japanese voice 120 seconds)
Mount of micro film
We had recruited the messages for micro flims since October 2006 to November 2006 as an outreach campaign, which was reported by a newspaper and other media. We received 800 messages from 1500 people. Yachiyo Micro Film Service supported the manufacturing of micro films. We really appreciate their support.
The mission of SEEDS-II is the same as that of SEEDS:
Downlink of housekeeping data by CW signal
Downlink of sensor data by FM packet (AX.25 protocol)
Attitude analysis using sensor data (gyro, geomagnetic sensor, and others)
Downlik of voice by digi-talker
Downlink of analogue image by SSTV signal
Thie right photo is a slide show of the snapshot of developmen of SEEDS-II. The development period was only 10 months, but we passed the communication test of ground station and satellite station without the space communication. After we exported SEEDS-II to University of Toronto, we continued the development of the operation software, the analysis of the power consumption using EM, and got ready for launch. The call sign of the ground station and satellite station is as follows:
SEEDS-II was exported to India in March 2008, 9 months after the export to Toronto. We conducted the flight operation at Satish Dawan Space Center before the launch. After that, SEEDS-II and other satellites were put on the PSLV rocket and launched in April 28, 2008. The launch was successful and the member of Satellite Lab have been oerating SEEDS now.
The below figures illustrates the ground station software (for tracking, downlink, uplink, and database), an example of SSTV image downlinked by amateur radio person ((DK3WN Mike san in Germany), and the analysis results of the downlink data.
SEEDS-II is used for outreach now. We hope you get the voice and SSTV signal from SEEDS-II!.