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Bochsler, Daniel C.

Publications and source records attributed to Bochsler, Daniel C..

11 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1989

Applications of graphics to support a testbed for autonomous space vehicle operations

Researchers describe their experience using graphics tools and utilities while building an application, AUTOPS, that uses a graphical Machintosh (TM)-like interface for the input and display of data, and animation graphics to enhance the presentation of results of autonomous space vehicle operations simulations. AUTOPS is a test bed for evaluating decisions for intelligent control systems for autonomous vehicles. Decisions made by an intelligent control system, e.g., a revised mission plan, might be displayed to the user in textual format or he can witness the effects of those decisions via out of window graphics animations. Although a textual description conveys essentials, a graphics animation conveys the replanning results in a more convincing way. Similarily, iconic and menu-driven screen interfaces provide the user with more meaningful options and displays. Presented here are experiences with the SunView and TAE Plus graphics tools used for interface design, and the Johnson Space Center Interactive Graphics Laboratory animation graphics tools used for generating out out of the window graphics.

Schmeckpeper, K. R.↗
NASA NTRS1988

A software engineering approach to expert system design and verification

Software engineering design and verification methods for developing expert systems are not yet well defined. Integration of expert system technology into software production environments will require effective software engineering methodologies to support the entire life cycle of expert systems. The software engineering methods used to design and verify an expert system, RENEX, is discussed. RENEX demonstrates autonomous rendezvous and proximity operations, including replanning trajectory events and subsystem fault detection, onboard a space vehicle during flight. The RENEX designers utilized a number of software engineering methodologies to deal with the complex problems inherent in this system. An overview is presented of the methods utilized. Details of the verification process receive special emphasis. The benefits and weaknesses of the methods for supporting the development life cycle of expert systems are evaluated, and recommendations are made based on the overall experiences with the methods.

Bochsler, Daniel C.↗
NASA NTRS1988

Research and development for Onboard Navigation (ONAV) ground based expert/trainer system: Preliminary ascent knowledge requirements

The preliminary version of expert knowledge for the Onboard Navigation (ONAV) Ground Based Expert Trainer Ascent system for the space shuttle is presented. Included is some brief background information along with the information describing the knowledge the system will contain. Information is given on rules and heuristics, telemetry status, landing sites, inertial measurement units, and a high speed trajectory determinator (HSTD) state vector.

Bochsler, Daniel C.↗
NASA NTRS1988

Research and development for Onboard Navigation (ONAV) ground based expert/trainer system: Test report

The test results for the onboard navigation (ONAV) Ground Based Expert System Trainer System for an aircraft/space shuttle navigation entry phase system are described. A summary of the test methods and analysis results are included. Functional inspection and execution, interface tests, default data sources, function call returns, status light indicators, and user interface command acceptance are covered.

Bochsler, Daniel C.↗
NASA NTRS1988

Research and development for Onboard Navigation (ONAV) ground based expert/trainer system: Preliminary test plan

The test plan for the onboard navigation (ONAV) expert system is described. Levels of testing are identified and the contributing role of each level for ensuring reliability is described. Also, the objectives of each type of test are identified and a summary of the test methods and the type of testing environment to be used is included. The ONAV expert system testing effort utilizes a multi-level verification approach. Five levels of testing are performed in essentially a serial manner: (1) individual rules, (2) ordered and unordered functional groups, (3) interface rules, (4) system tests, and (5) user tests. The intent is to catch the full range of both programming errors common to traditional programming and those errors characteristic of expert systems including factbase organization and inference engine interactions.

Bochsler, Daniel C.↗
NASA NTRS1988

Research and development for Onboard Navigation (ONAV) ground based expert/trainer system: Final user's guide

The purpose is to present procedures for preparation, operation, monitoring, and recovery of the Shuttle Onboard Navigation (ONAV) Entry phase expert system. This user's guide is primarily intended for functional users of the system. It includes procedures for system operation in support of training activities as well as operational tasks. In addition, information is provided which enables maintenance personnel to handle updates, modifications, etc. to the system.

Bochsler, Daniel C.↗
NASA NTRS1988

Research and development for Onboard Navigation (ONAV) ground based expert/trainer system: ONAV entry expert system code

A complete listing is given of the expert system rules for the Entry phase of the Onboard Navigation (ONAV) Ground Based Expert Trainer System for aircraft/space shuttle navigation. These source listings appear in the same format as utilized and required by the C Language Integrated Production System (CLIPS) expert system shell which is the basis for the ONAV entry system. A schematic overview is given of how the rules are organized. These groups result from a partitioning of the rules according to the overall function which a given set of rules performs. This partitioning was established and maintained according to that established in the knowledge specification document. In addition, four other groups of rules are specified. The four groups (control flow, operator inputs, output management, and data tables) perform functions that affect all the other functional rule groups. As the name implies, control flow ensures that the rule groups are executed in the order required for proper operation; operator input rules control the introduction into the CLIPS fact base of various kinds of data required by the expert system; output management rules control the updating of the ONAV expert system user display screen during execution of the system; and data tables are static information utilized by many different rule sets gathered in one convenient place.

Bochsler, Daniel C.↗
NASA NTRS1988

Research and development for Onboard Navigation (ONAV) ground based expert/trainer system: Preliminary user's guide

The purpose is to present procedures for preparation, operation, monitoring, and recovery of the Shuttle Entry phase expert system that is part of the Onboard Navigation (ONAV) Ground Based Expert System Trainer System for aircraft/space shuttle navigation. This user's guide is primarily intended for functional users of the system. It includes procedures for system operation in support of training activities as well as operational tasks. In addition, information is provided which enables maintenance personnel to handle updates, modifications, etc. to the system.

Bochsler, Daniel C.↗
NASA NTRS1987

Robotic space simulation integration of vision algorithms into an orbital operations simulation

In order to successfully plan and analyze future space activities, computer-based simulations of activities in low earth orbit will be required to model and integrate vision and robotic operations with vehicle dynamics and proximity operations procedures. The orbital operations simulation (OOS) is configured and enhanced as a testbed for robotic space operations. Vision integration algorithms are being developed in three areas: preprocessing, recognition, and attitude/attitude rates. The vision program (Rice University) was modified for use in the OOS. Systems integration testing is now in progress.

Bochsler, Daniel C.↗
NASA NTRS1987

Expert system isssues in automated, autonomous space vehicle rendezvous

The problems involved in automated autonomous rendezvous are briefly reviewed, and the Rendezvous Expert (RENEX) expert system is discussed with reference to its goals, approach used, and knowledge structure and contents. RENEX has been developed to support streamlining operations for the Space Shuttle and Space Station program and to aid definition of mission requirements for the autonomous portions of rendezvous for the Mars Surface Sample Return and Comet Nucleus Sample return unmanned missions. The experience with REMEX to date and recommendations for further development are presented.

Goodwin, Mary Ann↗