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Cline, Helmut P.

Publications and source records attributed to Cline, Helmut P..

Technology Readiness Level Assessment Process as Applied to NASA Earth Science Missions

Technology assessments of fourteen science instruments were conducted within NASA using the NASA Technology Readiness Level (TRL) Metric. The instruments were part of three NASA Earth Science Decadal Survey missions in pre-formulation. The Earth Systematic Missions Program (ESMP) Systems Engineering Working Group (SEWG), composed of members of three NASA Centers, provided a newly modified electronic workbook to be completed, with instructions. Each instrument development team performed an internal assessment of its technology status, prepared an overview of its instrument, and completed the workbook with the results of its assessment. A team from the ESMP SEWG met with each instrument team and provided feedback. The instrument teams then reported through the Program Scientist for their respective missions to NASA's Earth Science Division (ESD) on technology readiness, taking the SEWG input into account. The instruments were found to have a range of TRL from 4 to 7. Lessons Learned are presented; however, due to the competition-sensitive nature of the assessments, the results for specific missions are not presented. The assessments were generally successful, and produced useful results for the agency. The SEWG team identified a number of potential improvements to the process. Particular focus was on ensuring traceability to guiding NASA documents, including the NASA Systems Engineering Handbook. The TRL Workbook has been substantially modified, and the revised workbook is described.

Systems Engineering↗

The Tropical Rainfall Measuring Mission and the development of its observatory

The paper describes a cooperative program between NASA and NASDA, the Tropical Rainfall Measuring Mission (TRMM), which is an earth system science mission designed to study characteristics of the rainfall occurring over the tropics and subtropics. The salient features of the TRMM are described, with special attention given to the mission parameters, the instrument complement, the TRMM observatory, and the command and data handling subsystem. Also discussed are the TRMM requirement factors and the resulting approach to the TRMM observatory design.

Lavigna, Thomas A.↗

The development of Tropical Rainfall Measuring Mission (TRMM)

The Tropical Rainfall Measuring Mission (TRMM) is a joint-program between the U.S. and Japan. The objective of this international cooperative program is to carry out the systematic study of tropical rainfall required for major strides in weather and climate research. In this paper, launch operation, mission operation and data processing as well as the system design and development status of the TRMM satellite are presented.

Kozu, Toshiaki↗

Space Station user Servicing System architecture and operational aspects

The structure of the Space Station Servicing System architecture, operational aspects of the system, and the potential evolution of the servicing capabilities to accomodate a variety of missions are disscussed. Services to be performed include replacement or repair of failed modules, subsystems or parts, replacement or upgrading of spacecraft or instrument subsystems, replacement of limited lifetime subsystems or components, replenishment of consumables, and assembly of attached payloads and instruments. Elements of the system discussed include intravehicular servicing, the flight telerobotic servicer, and the mobile servicing center. Ground, preservicing, extravehicular and intravehicular servicing, and postservicing operations are examined. Also, a typical mission scenario for mature servicing operations is given.

Cline, Helmut P.↗

User assembly and servicing system for Space Station, an evolving architecture approach

On-orbit assembly and servicing of a variety of scientific and applications hardware systems is expected to be one of the Space Station's primary functions. The hardware to be serviced will include the attached payloads resident on the Space Station, the free-flying satellites and co-orbiting platforms brought to the Space Station, and the polar orbiting platforms. The requirements for assembly and servicing such a broad spectrum of missions have led to the development of an Assembly and Servicing System Architecture that is composed of a complex array of support elements. This array is comprised of US elements, both Space Station and non-Space Station, and elements provided by Canada to the Space Station Program. For any given servicing or assembly mission, the necessary support elements will be employed in an integrated manner to satisfy the mission-specific needs. The structure of the User Assembly and Servicing System Architecture and the manner in which it will evolved throughout the duration of the phased Space Station Program are discussed. Particular emphasis will be placed upon the requirements to be accommodated in each phase, and the development of a logical progression of capabilities to meet these requirements.

Lavigna, Thomas A.↗

Assembly of user systems at Space Station

The technical and programmatic benefits of on-orbit assembly are outlined. Operational and automation considerations relating to on-orbit assembly are reviewed. Space Station capabilities for orbital assembly are discussed.

Cline, Helmut P.↗

Satellite servicing in the Space Station era

The paper examines the lessons learned from past experiences, the requirements that apply to the various types of missions requiring servicing, and the present plans for establishing a system by which on-orbit servicing, assembly, and repair will become routine. It is noted that, by expanding on the servicing experience and capabilities provided directly by the STS, the Space Station will significantly enhance the mission objectives of long-duration scientific missions, not only by repair and consumable replenishment, but also by the addition and replacement of scientific instruments with upgraded versions. The servicing facility design is described, and a typical servicing scenario is presented.

Lavigna, Thomas A.↗

Automation and robotics and related technology issues for Space Station customer servicing

Several flight servicing support elements are discussed within the context of the Space Station. Particular attention is given to the servicing facility, the mobile servicing center, and the flight telerobotic servicer (FTS). The role that automation and robotics can play in the design and operation of each of these elements is discussed. It is noted that the FTS, which is currently being developed by NASA, will evolve to increasing levels of autonomy to allow for the virtual elimination of routine EVA. Some of the features of the FTS will probably be: dual manipulator arms having reach and dexterity roughly equivalent to that of an EVA-suited astronaut, force reflection capability allowing efficient teleoperation, and capability of operating from a variety of support systems.

Cline, Helmut P.↗