Space Acceleration Measurement System (SAMS) Control Unit

Disturbances of the on-orbit microgravity environment caused by crew motions, vehicle systems, attitude changes, etc. affect sensitive on-board science experiments. The SAMS is an acceleration measurement and data acquisition instrument designed to sense, measure, condition, and record low-level accelerations and vibrations; it documents the actual microgravity environment during experiment operations in space. This information is valuable for experiment data analysis and future experiment design.

The SAMS consists of a main control unit and as many as three remotely positioned triaxial sensor heads, each containing orthogonally positioned accelerometers. Cables connect the sensor heads to the main unit, which contains analog and digital signal processing circuitry and two optical disk drives for data storage.

SAMS units flew on more than 20 Space Shuttle missions (including Spacelab missions), numerous KC-135 flights, the Russian space station Mir, and the International Space Station to support microgravity science experiments. This particular SAMS (unit E) flew on Space Shuttle missions STS-43 (1991) and STS-47 (Spacelab J, 1992), and it was installed on Mir for four years (1994-1998), making it the U.S. equipment with the longest stay on Mir. While on Mir, it accumulated over 50 gigabytes of data (approximately 75 CD-ROMs), far exceeding its baseline operations for data collection on one-to-two week Shuttle missions. NASA transferred this equipment to the Museum upon its return from Mir.