on-board management unit
EREMS is responsible for the UGB.
The UGB computer has been designed to perform the following hardware functions:
- Power supply management provided by the PDU (28V) and mainly:
- ON/OFF of the PHARAO equipment
- Thermal regulation (heaters and peltiers coolers)
- Data handling protocol with the ACES XPLC computer using serial link (time tagging and synchronization with ACES),
- Data handling protocols with the PHARAO equipment,
- Control the on-board timing and synchronization (micro sequencer),
- TM/TC activities to control analogue housekeeping TMs and digital parameters.
The UGB overall dimensions are: 240 x 245 x 120 mm (7.3 l). The unit weight is near 5kg and the total power consumption is less than 30W. The computer is based onto five boards connected to a back frame
- CPU board
- Digital sampling board
- Analogue acquisition board
- Power heater board
- DC/DC converter boards
The context of the PHARAO project implies two constraints to the flight software, i.e. flexibility and ability to evolve.
Therefore, the main aspect of the PHARAO Flight Software is the definition of a software interpreter. The PHARAO flight software relies on two concepts: an interpreter and scientific sequences.
The Flight Software is constituted of three levels of software:
CS-SI is responsible for developing the Pharao flight software.