Engineering topics

Bercaw, Robert W.

Publications and source records attributed to Bercaw, Robert W..

7 records

NASA NTRS1994

Operational environments for electrical power wiring on NASA space systems

Electrical wiring systems are used extensively on NASA space systems for power management and distribution, control and command, and data transmission. The reliability of these systems when exposed to the harsh environments of space is very critical to mission success and crew safety. Failures have been reported both on the ground and in flight due to arc tracking in the wiring harnesses, made possible by insulation degradation. This report was written as part of a NASA Office of Safety and Mission Assurance (Code Q) program to identify and characterize wiring systems in terms of their potential use in aerospace vehicles. The goal of the program is to provide the information and guidance needed to develop and qualify reliable, safe, lightweight wiring systems, which are resistant to arc tracking and suitable for use in space power applications. This report identifies the environments in which NASA spacecraft will operate, and determines the specific NASA testing requirements. A summary of related test programs is also given in this report. This data will be valuable to spacecraft designers in determining the best wiring constructions for the various NASA applications.

Stavnes, Mark W.↗

NASA NTRS1991

Issues and status of power distribution options for space exploration

The Space Exploration Initiative (SEI) will need a wide variety of manned systems with requirements significantly different than those for existing systems. The concept of a space power utility is discussed and the impact of this concept on the engineering of space power systems is examined. Almost all existing space power systems use low voltage direct current. Although they have been very succesful, increasing power system requirements in recent years have exposed their inherent limitations and led to the proposal of a number of alternatives including high voltage DC and AC at various frequencies. Drawing on the experience gained from Space Station Freedom and SEI systems studies, factors that may affect the choice of frequency standards on which to build such a space power utility are discussed.

Bercaw, Robert W.↗

NASA NTRS1991

Electrical system options for space exploration

The need for a space power utility concept is discussed and the impact of this concept on the engineering of space power systems is examined. Experiences gained from Space Station Freedom and SEI systems studies are used to discuss the factors that may affect the choice of frequency standards on which to build such a space power utility. Emphasis is given to electrical power control, conditioning, and distribution subsystems.

Bercaw, Robert W.↗

NASA NTRS1989

Toward an electrical power utility for space exploration

Future electrical power requirements for space exploration are discussed. Megawatts of power with enough reliability for multi-year missions and with enough flexibility to adapt to needs unanticipated at design time are some of the criteria which space power systems must be able to meet. The reasons for considering the power management and distribution in the various systems, from a total mission perspective rather than simply extrapolating current spacecraft design practice, are discussed. A utility approach to electric power integrating requirements from a broad selection of current development programs, with studies in which both space and terrestrial technologies are conceptually applied to exploration mission scenarios, is described.

Bercaw, Robert W.↗

NASA NTRS1989

Toward an electrical power utility for space exploration

Plans for space exploration depend on today's technology programs addressing the novel requirements of space-based enterprise. The requirements for electrical power will be formidable: megawatts in magnitude, reliability for multi-year missions and the flexibility to adapt to needs unanticipated at design time. The reasons for considering the power management and distribution in the various systems from a total mission perspective, rather than simply extrapolating current spacecraft design practice, are discussed. A utility approach to electric power being developed at the Lewis Research Center is described. It integrates requirements from a broad selection of current development programs with studies in which both space and terrestrial technologies are conceptually applied to exploration mission scenarios.

Bercaw, Robert W.↗

NASA NTRS1987

Spacecraft 2000: The challenge of the future

Considerable opportunity exists to improve the systems, subsystems, components, etc., included in the space station bus, the non-payload portion of the spacecraft. The steps followed to date, the challenges being faced by industry, and the progress toward establishing a new NASA initiative which will identify the technologies required to build spacecraft of the 21st century and which will implement the technology development/validation programs necessary are described.

Brandhorst, Henry W., Jr.↗

NASA NTRS1986

Spacecraft 2000 program overview

The goals are to identify the critical need and technologies for spacecraft of the 21st century, and to recommend technology development and validation programs and possible government/industrial roles and partnerships. The objectives of the workshop are to increase awareness and exchange ideas among participants, highlight the spacecraft as a focal point for technology, and facilitate industry-government coordination.

Bercaw, Robert W.↗