Athenoxat 1st anniversay

[2016-12-16 Fri] speaker: Guilio Manzoni

Athenoxat is first low earth orbit, high resolution night vision Earth observation satellite

Low earth orbit is less than 2000km, at 7.5km/s

Main subsystems:

• on-board computers, ARM processor 2-64MB RAM, FreeRTOS
• Li-ion/Li-polymer battery
• attitude determination and control system
• command and data handling
• structures
• harness

New night imaging payload developed for Athenoxat

Testing against vibrations during launch and temperature cycling in space

Software

• OBC
  • FreeRTOS
  • C
• Day/Night imaging computer
  • Linux
  • C
• Ground control station
  • Linux

Communicate via HAM hardware

• every 90mins there is a 10min window

Able to harness sufficient power for operations

Five imaging systems on the satellite

Pointing the satellite: attitude control

• use the sun as reference
• base on the gyroscope
• magnetic field of the earth
• fisheye camera to find the center of the earth

Stabilization using Bdot

Wide angle imaging

• haze
• typhoon

Night imaging

• resolution about 20m
• pointing accuracy of less than 1 degree
• pointing stability
• able to spot ships

Download at 0.4kB/sec

Dealing with image noise

• setting the correct gain
• different gain needed for types of images