SHAD (Stellar Horizon Atmospheric Dispersion)
 The SHAD instrument was designed and built to measure the dispersion of starlight through the earths limb as a method of accurately determining spacecraft position.  In the program to  demonstrate autonomous navigation ITE provided design, analysis, fabrication, integration, test, planning and support for a Shuttle Launched Air Force Satellite.  Instrument highlights include:

  •   Az/el gimbaled system 0.6 arcsec pointing accuracy
  •   405" optical system, 6" primary Cassegrain telescope, 2" re-imaging Cassegrain telescope
  •   24 minute wide field acquisition using CCD
  •   16 second narrow field camera using quadrant photomultiplier
  •   5 microprocessor subsystems
  •   384 Star Catalog, orbit prediction observation generation software
  •   Software completely patchable via ground link

ITE performed system and subsystem design and analysis including the optical telescope, control systems, instrument power management, spacecraft telemetry and command interface, structural and mechanical systems design. ITE performed layout and packaging design of all electronics. ITE provided fabrication, assembly and subsystem and system integration in accordance with NASA & MIL specifications for the development of space flight hardware.Â

We developed and implemented program documentation including ICD's, safety plans, and contamination control plans; and performed safety and hazard analyses. We provided electrical and mechanical fabrication of the entire SHAD flight and GSE hardware to MIL and NASA standards.

ITE supported the integration of the instrument with the P80-1 at the Rockwell International's Seal Beach facilities. ITE performed alignment of the optical system, and performed a complete test program including vibration, thermal vacuum and EMI/EMC.

ITE developed extensive computer application programs including  software for in-flight operation including orbital computations, pointing and control from star catalog computations and instrument algorithm execution.  We also developed computer systems and software for data reduction and data distribution to the science community to support flight operations. ITE developed software for the formatting of command data uplinks, and decoding telemetry data via the USAF Spacecraft Control Facility (SCF).