NASA-HDBK-4001, ELECTRICAL GROUNDING ARCHITECTURE FOR UNMANNED SPACECRAFT

FOREWORD This handbook is approved for use by NASA Headquarters and all NASA Centers and is intended to provide a common framework for consistent practices across NASA programs. This handbook was developed to describe electrical grounding design architecture options for unmanned spacecraft. This handbook is written for spacecraft system engineers, power engineers, and electromagnetic compatibility (EMC) engineers. Spacecraft grounding architecture is a system-level decision which must be established at the earliest point in spacecraft design. All other grounding design must be coordinated with and be consistent with the system-level architecture. This handbook assumes that there is no one single "correct" design for spacecraft grounding architecture. There have been many successful satellite and spacecraft programs from NASA, using a variety of grounding architectures with different levels of complexity. However, some design principles learned over the years apply to all types of spacecraft development. This handbook summarizes those principles to help guide spacecraft grounding architecture design for NASA and others. Requests for information, corrections, or additions to this handbook should be directed to the Reliability Engineering Office, Mail Code 301-456, the Jet Propulsion Laboratory, 4800 Oak Grove Dr., Pasadena, CA 91109. Requests for additional copies of this handbook should be sent to NASA Engineering Standards, EL01, MSFC, AL 35812 (telephone 205-544-2448).

NASA-HDBK-4002, AVOIDING PROBLEMS CAUSED BY SPACECRAFT ON-ORBIT INTERNAL CHARGING EFFECTS

NASA TECHNICAL HANDBOOK. This handbook is approved for use by NASA Headquarters and all NASA Centers and is intended to provide a common framework for consistent practices across NASA programs. Its contents are equally applicable to any spacecraft. The handbook was developed to address the growing concerns associated with the in-flight buildup of charge on internal spacecraft components due to space plasmas with high energy electrons. Spacecraft charging, defined as the buildup of charge in and on spacecraft materials, is a significant phenomenon for spacecraft in certain Earth and other planetary environments. Design for control and mitigation of surface charging, the buildup of charge on the exterior surfaces of a spacecraft due to space plasmas, is treated in detail in NASA TP2361, " Design Guidelines for Assessing and Controlling Spacecraft Charging Effects" (September 1984). This handbook details some methods and techniques to mitigate internal charging. It is written as a companion document to NASA TP2361 and should be used in that context. Although many of the ideas presented here have a long heritage, this document collects them in one convenient place and quantifies and illustrates the design guidelines necessary to reduce the effects of internal charging. This handbook is intended to be an engineering tool, written for use by engineers. Much of the environmental data and material response information has been adapted from published and unpublished scientific literature for the purpose of this document. The authors would like to acknowledge the long history of scientific research from which this material has been obtained. The authors emphasize that the contents are a best effort at this time and may be subject to revision as more research is done. Requests for information, corrections, or additions to this handbook should be directed to the Reliability Engineering Office, Mail Code 301-466, Jet Propulsion Laboratory, 4800 Oak Grove Dr., Pasadena, CA 91109. Requests for additional copies of this handbook should be sent to NASA Engineering Standards, EL01, MSFC, AL, 35812 (telephone 256-544-2448). This and other NASA standards may be viewed and downloaded, free-of-charge, from our NASA Standards Homepage: http://standards.nasa.gov.

NASA-HDBK-4006, LOW EARTH ORBIT SPACECRAFT CHARGING DESIGN HANDBOOK

his handbook is published by the National Aeronautics and Space Administration (NASA) as a guidance document that provides engineering information; lessons learned; possible options to address technical issues; classification of similar items, materials or processes; interpretative direction and techniques; and any other type of guidance information that may help the Government or its contractors in the design, construction, selection, management, support, or operation of systems, products, processes, or services. This handbook is approved for use by NASA Headquarters and NASA Centers, including Component Facilities. This handbook provides design guidance for high-voltage space power systems (>55 volts) that must operate in the plasma environment associated with Low Earth Orbit (LEO). Requests for information, corrections, or additions to this handbook should be submitted via "Feedback" in the NASA Technical Standards System at http://standards.nasa.gov.

NASA-HDBK-5010, HANDBOOK FOR PAYLOADS,EXPERIMENTS, AND SIMILAR HARDWARE FRACTURE CONTROL IMPLEMENTATION

This handbook is approved for use by NASA Headquarters and all NASA Centers and JPL, and is intended to provide a common framework for consistent and acceptable practices across NASA programs. This handbook provides methodology and approaches for implementation of fracture control for payloads and experiments flown on the Space Shuttle and International Space Station. Following the guidelines of this handbook will satisfy the intent of the applicable NASA fracture control requirements for payloads and experiments as delineated in the Applicable Documents 1-9 in Section 4.1. Requests for information, corrections, or additions to this document concerning standards products may be submitted to the NASA Technical Standards Program Office via the Program Website. This and other NASA standards may be viewed and downloaded, free-of-charge, from our NASA Standards Homepage: http://standards.nasa.gov

NASA-HDBK-6003, APPLICATION OF DATA MATRIX IDENTIFICATION SYMBOLS TO AEROSPACE PARTS USING DIRECT PART MARKING METHODS/TECHNIQUES

NASA-HDBK-6003, APPLICATION OF DATA MATRIX IDENTIFICATION SYMBOLS TO AEROSPACE PARTS USING DIRECT PART MARKING METHODS/TECHNIQUES. This handbook provides requirements for applying Data Matrix identification symbols to parts used on NASA programs/projects using direct part marking (DPM) methods and techniques. While it is anticipated that this handbook will be used on new programs as well as those that are currently in the design phase, retrofit marking for hardware on existing programs is encouraged where feasible. The portions of this document addressing the application of human readable identification (HRI) markings does not apply to retrofit marking programs. Materials degradation and hazard analysis studies conducted on existing NASA programs were made under the assumption that a single HRI marking would be applied to each product. Consequently, the application of an additional Data Matrix marking to these parts will require the review of the applicable and engineering and program/project offices to ensure that product integrity is not compromised.

NASA-HDBK-7004B, FORCE LIMITED VIBRATION TESTING

FOREWORD This handbook is approved for use by NASA Headquarters and all Centers and is intended to provide a common framework for consistent practices across NASA programs. This first revision of the handbook includes force data measured in two flight experiments and a few minor editorial changes. The flight data provide validation of the force limiting methodology. The primary goal of vibration tests of aerospace hardware is to identify problems that, if not remedied, would result in flight failures. This goal can only be met by implementing a realistic (flight-like) test with a specified positive margin. In most cases, the goal is not well served by traditional acceleration-controlled vibration tests that indeed screen out flight failures, but in addition may cause failures that would not occur in flight. The penalty of over testing is manifested in design and performance compromises, as well as in the high costs and schedule overruns associated with recovering from artificial test failures. It has been known for 30 years that the major cause of over testing in aerospace vibration tests is associated with the infinite mechanical impedance of the shaker and the standard practice of controlling the input acceleration to the frequency envelope of the flight data. This approach results in artificially high shaker forces and responses at the resonance frequencies of the test item. To alleviate this problem it has become common practice to limit the acceleration responses in the test to those predicted for flight, but this approach is very dependent on the analysis that the test is supposed to validate. Another difficulty with response limiting is that it requires placing accelerometers on the test item at many critical locations, some of which are often inaccessible. The advent of piezoelectric triaxial force gages has made possible an alternative, improved vibration-testing approach based on measuring and limiting the reaction force between the shaker and test item. Piezoelectric force gages are robust, relatively easy to install between the test item and shaker, and require the same signal conditioning as piezoelectric accelerometers commonly used in vibration testing. Also vibration test controllers now provide the capability to limit the measured forces and thereby notch the input acceleration in real time. To take advantage of this new capability to measure and control shaker force, a rationale for predicting the flight-limit forces has been developed, validated with flight measurements, and applied to many flight projects during the past five years. Force limited vibration tests are conducted routinely at the Jet Propulsion Laboratory (JPL) and also at several other NASA Centers, Government laboratories, and many aerospace contractors. This handbook describes an approach that may be used to facilitate and maximize the benefits of applying this relatively new technology throughout NASA in a consistent manner. A NASA monograph, NASA-RP-1403, which provides more detailed information on the same subject, is also available for reference.

NASA-HDBK-7005, Dynamic Environmental Criteria Technical Handbook

This handbook is approved for use by NASA Headquarters and all field centers and is intended to provide a common framework for consistent practices across NASA programs. A concerted effort is underway within the NASA engineering community, under the cognizance of the NASA Office of the Chief Engineer, to promote more consistent practices across the NASA centers in the areas of dynamics and structures design and test criteria for spacecraft and payloads. This effort has resulted in NASA standards in the fields of structural design and test factors of safety, loads analyses, vibroacoustic test criteria, and pyroshock test criteria. A parallel effort, also funded by the Office of the Chief Engineer, was undertaken by the Jet Propulsion Laboratory and its contractors to summarize and assess mission dynamic environments, state-of-the-art procedures for predicting the dynamic excitations or loads induced by those environments and the structural responses to those excitations, and for establishing dynamics criteria with appropriate margins for the design and testing of a spacecraft and its components, along with the equipment and procedures used for testing. Contributions were made to this handbook by many members of the aerospace dynamics community; those contributions are gratefully acknowledged. Requests for information, corrections, or additions to this handbook should be directed to the Mechanical Systems Engineering and Research Division, Section 352, Jet Propulsion Laboratory, 4800 Oak Grove Dr., Pasadena, CA 91109. Requests for general information concerning technical standards should be sent to the NASA Technical Standards Program Office, ED41, MSFC, AL, 35812 (telephone 256-544-2448). This and other NASA standards may be viewed and downloaded, free-of-charge, from our NASA Standards Homepage: http://standards.nasa.gov (Original Signed By) W. Brian Keegan Chief Engineer