F-1 (satellite)
F-1, formally known in Vietnam as Vệ tinh nano F-1, was a Vietnamese CubeSat built by FSpace laboratory, FPT University in partnership with Angstrom Space Technology Center, Uppsala University, Sweden and Nanoracks, an American company.
The satellite
Hardware
- Structure: aluminium alloy T-6061
- Power supply: body-mounted solar cells, rechargeable Li-Polymer battery
- PIC16 and PIC18 micro-controllers
- Yaesu VX-3R handheld transceivers
- C328 low-resolution camera
- Temperature sensors
- Three-axis magnetometer
- 2-meter band and 70-cm band dipole antennas
Specifications
- Size:
- Mass:
- Communication: 2 independent radios using amateur radio Very high frequency and Ultra high frequency bands, transmission speed 1200 bit/s; AFSK and PWM Morse code modulation, KISS protocol
- Payload: low resolution C328 camera
- Sensors: temperature sensors and three-axis magnetometer
- Targeted orbit lifetime: at least 3 months on orbit
Communication subsystem and packet format
Backup UHF channel
- Only operational in daylight
- Frequency: 437.485 MHz
- Modulation: Narrow FM
- Power: about 0.2 watt RF output
- Antenna: half-wave dipole
- Beacon interval: 20 seconds duration, repeated every 90 seconds
- Pulse-Width-Modulation Morse code telemetry beacon, as follows:
| No1 | Data | Description | Size | Size |
| 1 | F-1's callsign | "XV1VN" | 5 | |
| 2 | OBC1 reset count | Number of OBC1's reset since the beginning | 8 | |
| 3 | Temperature 1 | °C | 8 | 5 |
| 4 | Temperature 2 | °C | 8 | |
| 5 | Checksum bit | 0 if summary of items #2 to #4 is even, 1 if it is odd | 1 | |
| Total | 10 |
Main VHF channel
- Operational during night time but may be turned on in daylight later
- Frequency: 145.980 MHz
- Modulation scheme: AFSK/FM
- Power: 1.0 watt RF output
- Antenna: half-wave dipole
- Baud rate: 1200 bit/s
- Telemetry and interval: one burst of 3 telemetry packets in KISS format every 30 seconds
| No | Data | Description | Size |
| 1 | Date time | Date: dd/mm/y: 5/4/3=12 bits Time: hh/mm/ss: 5/6/6=17 bits | 29 |
| 2 | Battery voltage | Battery voltage multiplied by 100 | 11 |
| 3 | Solar cells voltage | Solar cells voltage multiplied by 10 | 8 |
| 4 | Temperature 1 | °C | 8 |
| 5 | Temperature 2 | °C | 8 |
| 6 | Temperature 3 | °C | 8 |
| 7 | Temperature 4 | °C | 8 |
| 8 | Temperature 5 | °C | 8 |
| 9 | Temperature 6 | °C | 8 |
| 10 | Temperature 7 | °C | 8 |
| 11 | Temperature 8 | °C | 8 |
| Total | 112 bits = 14 bytes |
Note:
- Periodically, F-1 would send a burst of 3 telemetry packets with the same content, to avoid packet loss
- Time in UTC, 24 hours format
- Year count starting from 2012
- Battery voltage reading is accurate to 0.01 volt, values are multiplied by 100. Divide by 100 to get actual value.
- Solar cells voltage reading is accurate to 0.10 volt, values are multiplied by 10. Divide by 10 to get actual value.
- Temperature readings from sensors, will be added with 100 before transmission to ensure a positive number so please subtract 100 to get actual value
- 112 bits, divided into 14 bytes
Manufacturing process
In late 2008, plans for a small satellite were submitted to FPT Software. In early 2009, FSpace laboratory was founded.F-1 was initially planned to have a dimension of and a mass of. Later, the satellite's dimension and mass were revised to be and respectively.
Mission
F-1 was planned to train young engineers and students about aerospace engineering and evaluate an advanced three-axis magnetometer, Spin-Dependent Tunneling Magnetometer designed in Sweden by ASTC.Launch and status
Initially, F-1 was planned to be launched in late 2010.F-1 was launched on 21 July 2012 and delivered to the International Space Station aboard Kounotori 3 along with the RAIKO, WE WISH, Niwaka and TechEdSat-1 cubesats. Then, on 4 October 2012, it was deployed into orbit from the ISS using the JEM-Small Satellite Orbital Deployer which was attached to the Kibō module's robotic arm.
As of 2 November 2012, F-1 failed to confirm communication after the orbital deployment.
F-1 decayed on 9 May 2013.