Dawn

Satellite

Dawn with Vesta and Ceres against Hartmann background.

Background

Two identical Framing Cameras[External] (FC) are the scientific imaging system of the Dawn spacecraft, providing cold redundancy also for optical navigation. To obtain two-dimensional images in one broadband and seven narrow band spectral channels, each camera is equipped with a filter wheel in front of the single CCD sensor. The sensor provides a resolution of 1024 x 1024 pixels. Each camera is controlled and its data is processed by a Data Processing Unit (DPU), which was completely developed and verified at IDA. An enhanced version of the VMC "System-on-Chip (SoC)" approach is used by implementation of all functionalities together with a SPARC-V8 compatible LEON2 processor core within reprogrammable Xilinx FPGAs. Including an internal camera image mass memory of 8 Gbit, the complete processor system has a volume of 600 cm3, a mass of 520 g and a power consumption of less than 7 W. The real-time operating system RTEMS is used as basis for a complete instrument control and on-board data processing system, implemented in a sophisticated on-board command language (OCL).

Mission Milestones

References

• Nice summary article: ​http://www-ssc.igpp.ucla.edu/dawn/pdf/DawnStatusReport.pdf
• ​http://www-ssc.igpp.ucla.edu/dawn/
• ​http://www.mps.mpg.de/projects/dawn/
• ​http://www.ida.ing.tu-bs.de/index.php?id=842&L=2