SSETI Swarm – A student multi-spacecraft autonomous formation of pico-satellites, OBDH team description

The SSETI Swarm mission is a project of the Student Space Exploration and Technology Initiative association (SSETI), developed thanks to the work of students from five different European and non-European universities (Italy, Spain, Portugal, Czech Republic and Canada).

Its ambitious goal is the realization of a multi-spacecraft formation (a "swarm") of very small satellites. A double Cubesat configuration is designed so that all service subsystems (communication, GNC, power, OBDH) are accommodated in one of the Cubesat units (the Mother‑Satellite, or M-Sat), while the second Cubesat unit, structurally joint to the first one, contains the swarm members, each one of the dimensions of a quarter of Cubesat; since they are smaller than a pico-satellite, they are called "femto-satellite", or F-Sats. Once in orbit, the M-Sat, thanks to an electro-thermo-mechanical system, will deploy the swarm members, each one carrying a specific payload: micro-thrusters and integrated chip imager demonstrators, coarse dosimeters and a coarse attitude control system (flywheel). The communication architecture is made up of a direct link from the F-Sat towards the M-Sat, while ground uplink and downlink for telemetry, command and F-Sats' payload data will be accomplished by M-Sat. The technological issues of the mission, such as miniaturization of subsystems and autonomous communication capabilities represent challenges for all the people involved, and a powerful attractive in particular for the students, which represent the core members of the teams.

The SSETI Swarm mission is the first SSETI project where students from the Czech Republic are participating. Concretely the OBDH (On-Board Data Handling) team has been established at Czech Technical University in Prague (CTU). It has arisen on the basis of student activity with great support from Vice-Rector for Student Affairs. The main OBDH team assignment is to design a satellite module for On-Board Data Handling in the SSETI Swarm mission. We focus on connections between all satellite modules, the choice of microcontroller architecture and suitable memory chips, and programming efficient and safe system software. Finding the solution to all these issues requires considering space conditions, including radiation exposure impact and large changes in temperature. The lowest module power consumption is an important factor as well.

Currently the team consists of three members:

Ondřej Daniel - student at Faculty of Electrical Engineering, CTU, Field of Study Telecommunications and Radio Engineering. Ing. Degree (equivalent to M.Sc.) expected in 2010. Team leader and author of idea to join to SSETI program by Czech students. Solver of the OBDH task.

Jiří Novák - student at Faculty of Electrical Engineering, CTU, Field of Study Computer Science and Engineering. Ing. Degree (equivalent to M.Sc.) expected in 2009. Solver of the OBDH task.

Radim Roška - student at Faculty of Electrical Engineering, CTU, Field of Study Computer Science and Engineering. Ing. Degree (equivalent to M.Sc.) expected in 2010. Responsible for team server administration and IT issues.CTU Student team works on the project SSETI Swarm. From left Radim Roska, Jiri Novak and Ondrej Daniel.