STECCO

STECCO [GAUSS]

STECCO (Space Travelling Egg-Controlled Catadioptric Object) is a nanosatellite composed by 6 PocketQube units (5x5x5 cm3) with a total mass of 0.85 kg and an envelope of 5 cm × 5cm × 30 cm designed and built by the students of the Special Master of Aerospace Engineering offered by School of Aerospace Engineering (Sapienza University of Rome), who designed the satellite structure, implemented the flight software, programmed the mission profile and managed the integration and testing, under the supervision of the professors and researchers of the School.

STECCO features several experiments:

• STECCO has a radioham digipeater which is active by default and can be accessed by any radioamateur.
• Satellite Laser Ranging (SLR) allows precise positioning of the satellite with respect to a laser ranging ground station, by means of the Cubic Corner Reflector (CCR) mounted on the tip faces of STECCO. The CCRs that are used are commercial-of-the-shelf (COTS) units. The use of COTS reflectors has been approved by ILRS and tested on small university mission, and has been approved for the ASI LARES 2 scientific satellite.
• Attitude Determination and Control
  • The TRIAD algorithm is implemented on-board the FPGA section of PHOEBE OBC. The algorithm provides Attitude Determination from the input of the 12-bit MEMS three-axis magnetometer and gyroscope and geomagnetic field extracted from the IGRF model and stored on-board.
  • The use of two COTS CCRs makes possible to estimate the Attitude of STECCO from ILRS data. In particular, the angle from nadir direction and the angular rates of STECCO can be extrapolated from SLR and propagated to infer the whole attitude state of STECCO. Feasibility studies have been performed to verify the suitability of the technique, that will be validated during the flight of STECCO.
  • STECCO will validate in space the Magnetic Attitude and Rate Determination (MARD) algorithm, which allows estimating the attitude and angular rates of the satellite based on the data of a single three-axis magnetometer. The algorithm studied and Hardware-in-the-Loop simulations were performed using the Helmholtz cage at the School of Aerospace Engineering.
  • The attitude control of STECCO is performed by means of passive techniques including gravity-gradient stabilization and viscous damping. The effectiveness of a viscous damper, named the "EGG", capable of storing the angular momentum of the satellite and dissipate its rotational kinetic energy, will be tested in-orbit.

STECCO was launched in March 2021 and will be deployed from the UniSat 7 satellite.