The Materials and Processes Laboratory, located in the Vehicle Assembly Building (VAB), supports External Tank (ET), Solid Rocket Booster (SRB), and Orbiter efforts with in-process testing for a variety of materials, including adhesives, foams, ablatives, and films.

Pulling things apart has been a traditional source of parental disapproval for quite some time. However, at the Materials and Processes Laboratory, it is their job. The lab uses a Tinius-Olsen (T-O) 10,000-pound Universal Testing Machine to evaluate tensile strength. This “evaluation” is destructive testing: the T-O machine literally rips various materials apart and records the points at which they fail.

One of these materials is RT-455, a trowelable thermal ablative compound used for Thermal Protection Systems on the SRB’s. During SRB flight set processing, technicians make approximately 500 tensile samples, one for each gallon of material mixed. It is extremely important to accurately record the sample identification, type of failure, and the exact force at which the sample failure occurs. The Ablative Test Tracking software performs this task. The lab previously used DOS-based software for its RT-455 ablative tracking requirements, but that software was technologically obsolesced by both the passage of time and the introduction of Windows.

The software team and design team chose Oracle Forms on a Microsoft Windows platform for the user interface. This provided current database technology. However, Oracle Forms did not provide the special-purpose communication functions this effort required. In response, the software team embedded C++ function calls within the form. This allowed the user to simply press an on-screen button to initiate two-way communication with the Tinius-Olsen via a serial port. This digital interface to an analog device allowed the software to automatically direct the operation of the T-O machine and receive the test values in return.

The C++ functions significantly extend tracking capabilities. These on-screen objects provide real-time display of T-O operational values and display dialog boxes for direct user interaction as required. Although they automatically initiate the T-O and start testing, the software still preserves all manual backup capabilities. There is also an on-screen abort button to immediately terminate a test if necessary.

Advances in communication technology make the direct interface of a test process and its tracking software both convenient and practical. It avoids the duplication of effort (and errors) involved when using a human being and keyboard to interface an analog device to a database.

The Ablative Test Tracking software provides the Materials and Processes Laboratory with a convenient and accurate way to automatically record and report their tests. It gives better support to SRB processing with automatic recording of values from the test-generating device directly to the tracking and reporting software. Testing performed includes ablative application tensile strength and density, spray-on foam insulation tensile and density, troubleshooting of material-related problems, and Orbiter lap-shear testing of adhesives and films.

Key accomplishment:

• 2002: Integration of C++ communications modules into Oracle Forms.

Key milestone:

• 2002: Program designed, coded, and fully implemented.

Contact: P.J. Bookman (Pamela.Bookman-1@ksc.nasa.gov), YA-C1, (321) 867-6381
Participating Organization: United Space Alliance (S.M. Schneider, A.M. Foderousky, G. Lebovitz, and A. Beckus)