Wireless Data Acquisition System (WDAS)


A Wireless Data Acquisition System was developed for NASA Johnson Space Center (JSC) to be used ultimately on the International Space Station (ISS) as well as for many experimental applications on the Shuttle. The foundation for this system began with the prototype Sensor Control and Telecommunications System (SCAT).  Phase II development for the WDAS started in 1994 and concluded in 1996

The system includes individual data gathering units that are autonomous (battery-operated) and thus can be positioned in and on the Shuttle and ISS with a minimum of integration cost. Sophisticated power management and the network command and control concept provide long-term operation on primary batteries. The system operates on a “smart” wireless network that can be operated from a PGSC in the Shuttle Crew Cabin or from Mission Control on the ground.  The system can also be tested remotely during preflight checkout and thus reduce previous requirements for Crew Cabin access.

The WDAS system consisted of 3 RSUs (Remote Sensor Units) each with 8 channels of temperature input and one NCU (Network Control Unit). The RSUs were deployed on the longeron rails in the Cargo Bay of the Shuttle. The system operated for one week on the Launchpad gathering temperature data from a simulated hot nitrogen purge to be used on ISS structural loads. At the end of the purge simulation, the units were placed into a data-gathering mode for the mission.

This system was developed on an Small Business Innovation Research (SBIR) project for NASA JSC; first sales of the product to NASA on a commercial basis occurred in 1996. This has been followed in 1997 by sales of a version of the data acquisition network that was used to instrument the parafoil for the X-38 ISS lifeboat program.

An experimental version of the system, ADDS (Autonomous Dynamic Data Sensor), flew on STS-80 aboard the Wake Shield Facility to test various sensors.  A development test objective program RME1330 flew aboard the Shuttle on STS-83 (April 1997) and STS-94 (July 1997).  The system performed beyond expectations on both flights without interim servicing.

The success of the WDAS experiment spurred NASA to award another Phase III contract for IWIS™ (Internal Wireless Instrumentation System) and SWIS™ (Shuttle Wireless Instrumentation System) to apply the technology to environmental monitoring on the International Space Station (ISS).