VELOX-II Nano-satellite

VELOX-II is an advanced nano-satellite [9kg (satellite), 4kg (deployer), total 13kg]. It is also the second nano-satellite built by NTU. This project is in collaboration with Addvalue Innovation Pte Ltd. Besides the primary communication payload, it carries a GPS payload for precision navigation and a fault tolerant electronic circuit.

Objectives

  • To design, build and launch the first 6U nano-satellite in the world with inter-satellite communication capability between a LEO and higher orbit satellites
  • To demonstrate data downlink anywhere anytime in orbit without passing the ground station.
  • To demonstrate precision navigation and fault tolerant electronics​​
VELOX-II Nano-satellite
Dimensions​​​​​120mm x 246mm x 340.5 mm (stowed)
​Mass​9kg (satellite), 4kg (deployer), total 13kg
​Orbit​Near equatorial LEO orbit, 550km altitude
​Attitude determination & control system​3-axis stabilized and controlled with 1 GPS receiver, 2 IMUs, fine and coarse sun sensors, 3 magnetic torquers and 3 reaction wheels
​On-board data handling​Mainboard with 100 MHz 8051 MCU, 2Gb SD card, UART and I2C data interfaces
​Communication​9600bps BPSK downlink / 1200bps AFSK uplink, UHF & VHF dipoles ( VELOX-II Beacon Information)
​Power subsystem​2 deployable GaAs 6U panels (2s5p x 4 channels) for 40.8W peak, 2 fixed 3U panels (6W per channel), 11.6Ah @ 7.2V nominal Li-ion battery
Structure​​Al. 7075/Al. 6082 chassis with stainless steel load bearing parts; solar panel deployment mechanism
Thermal control​​Multi-Layer Insulation (MLI)
​Payloads​Inter-satellite communication system, GPS & fault tolerant electronics
​Ground segment​​​Ground station in NTU campus with UHF/VHF high-gain cross-yagi antennas
Predicted TLE
2015-077F               

1 41171U 15077F   15361.70139708  .00005939  00000-0  33642-3 0  9992
2 41171  14.9928 128.6656 0010895 142.0957 340.3297 15.07685517  1659

To celebrate Singapore’s Golden Jubilee, the VELOX-II CW beacon header has been changed to ssg50 from 30 Dec 2015​

Internal view o​f VELOX-II

GP​S payload

Fla​t satellite

Fla​t satellite

Testing of satellite re​​action wheels