The goal of interface management is to identify, define, control, and verify interfaces; ensure compatibility; provide an efficient system development; be on time and within budget; while meeting stakeholder requirements. This paper will present a successful seven‐step approach to interface management used in several prior NASA flight projects. The seven‐step approach using Model Based Systems Engineering will be illustrated by interface examples from the Materials International Space Station Experiment‐X (MISSE‐X) project. The MISSE‐X was being developed as an International Space Station (ISS) external platform for space environmental studies, designed to advance the technology readiness of materials and devices critical for future space exploration. Emphasis will be given to best practices covering key areas such as interface definition; writing good interface requirements; utilizing interface working groups; developing and controlling interface documents; handling interface agreements; the use of shadow documents; and the importance of interface requirement ownership, interface verification, and product transition.

We investigate the size and crystal orientation of each small grain of ferroelectric SrBi 2 (Ta,Nb) 2 O 9 (SBTN) films within very small areas by an electron backscatter diffraction (EBSD) analysis technique. The obtained map of the grains reveals that the size of c-axis-oriented grains increases as the average grain size of the films increases. On the other hand, the size of a-axisoriented grains, each of which has a finite remnant polarization normal to the films, is almost unchanged. The area fraction of the a-axis-oriented grains is in good agreement with the measured polarizations of ferroelectric capacitors with different average grain sizes. This result implies that an increase in the number of relatively small a-axis-oriented grains is effective for increasing the total polarization of the ferroelectric films. The demonstrated analysis technique is very useful for the precise design of future high-density ferroelectric random access memories (FeRAMs) with very small capacitor structures, each of which consists of only a few grains.

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Mass memory systems based on rewriteable optical disk media are expected to play an important role in meeting the data system requirements for future NASA spaceflight missions. NASA has established a program to develop a high performance (high rate, large capacity) optical disk recorder focused on use aboard unmanned Earth orbiting platforms. An expandable, adaptable system concept is proposed based on disk Drive modules and a modular Controller. Drive performance goals are 10 gigabyte capacity, 300 megabit per second transfer rate, 10-12 corrected bit error rate, and 150 millisecond access time. This performance is achieved by writing eight data tracks in parallel on both sides of a 14 inch optical disk using two independent heads. System goals are 160 gigabyte capacity, 1.2 gigabits per second data rate with concurrent 1/0, 250 millisecond access time, and two to five year operating life on orbit. The system can be configured to meet various applications. This versatility is provided by the Controller. The Controller provides command processing, multiple drive synchronization, data buffering, basic file management, error processing, and status reporting. Technology developments, design concepts, current status including a computer model of the system and a Controller breadboard, and future plans for the Drive and Controller are presented.