September 30, 2016

Satellite modes

The satellite can operate in 4 different modes:

  • OFF mode: the satellite is in OFF mode when all satellite units are switched off. The OFF mode is used on the ground for transportation, during satellite Assembly Integration and Test (AIT) phase when no activity is ongoing, and at the end of the disposal phase.
  • LAUNCH mode: the satellite is in LAUNCH mode when it is setup on the launcher, all satellite units are switched off, and the separation detection device is armed. In consequence, the satellite is in LAUNCH mode from the last satellite on-ground operations before the transfer onto the launch vehicle and until the launcher/satellite separation. Once the LAUNCH mode is terminated, the satellite is autonomously switched on, the solar array is deployed, and the SURVIVAL mode is engaged.
  • SURVIVAL mode: The SURVIVAL mode is a configuration in which power consumption is minimised, with an autonomous state providing safe and stable power, thermal, and operational conditions for as long as necessary. The SURVIVAL mode is used as a backup mode at any time in response to a major anomaly. Satellite functions and powered units used in satellite SURVIVAL mode are limited to the minimum required to ensure stable conditions.
  • NORMAL OPERATING mode: in NORMAL OPERATING mode, the satellite is fully operational, the platform and the payload provide all functionalities, particularly the mission's scientific measurements.

The animation below shows the different satellite modes (except OFF mode) one after the other (LAUNCH mode - SURVIVAL mode - NORMAL OPERATING mode). Rotation speed and duration of each modes isn't to scale, especially for the SURVIVAL mode (after launch vehicle separation) which will be significantly longer.