The Operations Impact Assessor (OIA) computer program facilitates rapid assessment of the effects of designs of spacecraft on spacecraft-processing operations at a launch site. OIA is a user-friendly, object-oriented, artificial-intelligence application program that features model-based reasoning and scheduling of discrete events.

The OIA enables the user to quickly develop a semantic model of a conceptual launch vehicle and its processing at a launch site to assess the effects of various elements of the design of the vehicle on the processing operations. The assessments can include evaluations of operability and processing requirements pertaining to such things as ground support equipment, utilization of facilities, labor, and processing schedules.

The use of the OIA proceeds in three stages: construction of a model of the launch vehicle, development of a model of process flow, and generation of an operational time line. The OIA consists of three major components — intelligent assistants, the knowledge base, and utilities. The combination of these components provides an integrated operations-modeling environment. The OIA exploits an object-oriented frame system to store a model of the vehicle, resources, attributes, and schedules. Following a model-view-controller approach, the software can provide alternate views into the same knowledge base.

The intelligent-assistants component of the OIA includes two intelligent assistants to aid in construction and evaluation of semantic models. The Vehicle Definition Assistant (VDA) helps the user in quickly constructing a model of a conceptual launch vehicle by defining its components, subsystems, systems, and hierarchical relationships among them. The Operations Definition Assistant (ODA) helps the user define and assess launch-vehicle-processing flow, time lines, and requirements.

The knowledge base contains an extensive, expandable collection of data on launch vehicles and components thereof. It also contains data on processing and resources pertinent to launch vehicles and their components. The knowledge base is contained in a common template library and individual project libraries. The user gains access to the vehicle data via the VDA and to the processing and resource data via the ODA.

The utilities component of the OIA includes three major software utilities that support the intelligent assistants. One utility is the Assessment Tool, which prepares a schedule of the vehicle-processing flow for comparison with other vehicle flows. Another utility is the Reporting Tool, which generates time lines, resource histograms, and other reports in different formats to identify and display the effects on schedules and resources. The Reporting Tool is also used to format and transmit the output of the Assessment Tool for printing or for use in other computer programs. The third utility is the Model Management utility, which provides a link between the intelligent assistants and the internal sources of data. While functioning automatically in the background, this utility also enables the storage and retrieval of models and provides access to both internal and external sources of data.

This work was done by John J. Cwiklinski, Robert B. Sieck, Jr., and Roy C. Tharpe, Jr., of McDonnell Douglas Corp. for Kennedy Space Center.For further information, access the Technical Support Package (TSP) free on-line at under the Mathematics and Information Sciences category, or circle no. 129 on the TSP Order Card in this issue to receive a copy by mail ($5 charge).

Inquiries concerning rights for the commercial use of this invention should be addressed to

the Patent Counsel
Kennedy Space Center; (407) 867-2544.

Refer to KSC-11836.