Autonomous Passive Optical Staring Of LEO Flying Objects (Apparillo)

Brief description

The APPARILLO is an integrated system for monitoring the near-Earth orbit. Equipped with a sensitive, high-resolution astro camera and a wide-angle lens, it detects and measures objects illuminated by the sun at dusk.

Applications

  • Space surveillance
  • Optical detection of orbital objects
  • New discovery of uncatalogued objects (satellites and space debris)
  • Cost-effective alternative to radar sensors
  • Transportable and self-sufficient system to supplement existing networks

Facts and figures

  • Detection of ~500 objects per night at up to 162 objects / h
  • Detection threshold (minimum object size): 0.4 m
  • Measuring accuracy: 100 m
  • Exposure time: 1 s
  • Mass 200 kg

The APPARILLO (Autonomous Passive Optical Staring Of LEO Flying Objects) is an integrated system for monitoring low-Earth orbit. APPARILLO can autonomously capture and process images of solar-illuminated objects in low-Earth orbit. Housed in a weatherproof enclosure and equipped with extensive control and image processing software, the system can measure the angular positions of orbital objects and forward them to existing databases.

The images are taken by a sensitive astro camera with a powerful wide-angle lens (up to 20° field of view). A GPS timer ensures that the images are precisely timed. With an exposure time of 1 second, passing orbital objects produce a line trace that is clearly distinguishable from the star background.

An astrometry module recognises stars in the image and uses their known positions to determine the equatorial coordinates of the start and end points of the line traces. This eliminates the need for precise alignment of the sensor.

The data of the detected objects is made available in standardised formats (e.g. Tracking Data Message, TDM) and can either be archived or sent to a server for further processing. The measurement accuracy of the orbital objects located using the method described is 100 metres in the direction of flight (along-track) and 100 metres perpendicular to the direction of flight (cross-track).

An even higher orbital accuracy of the objects initially detected with APPARILLO can subsequently be achieved by distance measurements with a laser-based (SLR) ground station.

Contact

Wolfgang Riede

Head of department
German Aerospace Center (DLR)
Institute of Technical Physics
Active Optical Systems
Pfaffenwaldring 38-40, 70569 Stuttgart