UNISAT-4
UniSat-4 is the fourth educational microsatellite of the UNISAT program, built and designed by students and professors of the School of Aerospace Engineering.
Characteristics
UniSat-4 structure is based on the design of the previous three satellites, an octagonal prism (150mm each side and 250 mm the height) realized in honeycomb with four alluminium “sandwich” trays assembled by columns, where the subsystems are located
Mass of almost 13kg
Power: photovoltaic system and Ni-Cd batteries (connected)
Passive magnetic attitude stabilization system to stabilize the spacecraft
Orbit: Sun-synchronous orbit, altitude = 500/750 km, inclination = 98º
S-band transmitter, uplink receiver frequencies 436.450MHz, power 2W
Commercial off-the-shelf components
Mission Objectives and Payload
Promoting Space culture
Stimulating Space engineering students practical trainings
Experiments: tests of the behavior in Space environment of terrestrial solar cells; Earth magnetic field and measurements for attitude determination; communication links test
Plasma parameter measurements
Experimental sails
TPS (Triple Probe System) for pre-earthquake analysis
GPS (navigation) experiment
MPPT(Maximum Peak Power Tracking)
Two COTS Cameras with different resolution
COTS Magnetometers
Triple junction solar arrays
Peak power tracking MPPT
Deorbiting re-entry device innovative passive mechanism developed by GAUSS (SIRDARIA –
Spacecraft Integrated Reentry Device Aero Resistant Increasing Area
GPS receiver
Langmuir Probe (INAF, IFSI)
S-band transmitter installed onboard digital communication channel in the UHF/VHF bands
Launch
The launch took place on July 26, 2006 from Baikonur with DNEPR rocket from Baikonur Cosmodrome, Kazakhstan. UniSat-4 formed part of a record Cluster launch of 18 university satellites: the LV (DNEPR rocket from ISC Kosmotras) hosted onboard 14 CubeSats from 10 different universities and one Company, coordinated by California Polytechnic State University (CalPoly) weighting 1kg each and measuring 10x10cm; plus the Bielorus satellite Belka 1 for Earth observation (weighting 700kg), UniSat-4 and the Italian PiCPoT educational microsatellite developed and built by the University Politecnico di Torino (2,5 kg, cubic shape). This time the launch was not successful, as the DNEPR had an issue after 74 seconds after launch.