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A. Introduction

B. Institutional Requirements

C. Project Software Requirements

D. Topics

E. Tools, References, and Terms

F. SPAN
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Excerpt

This section of the SWEHB is reserved for the development of a set of Human Rated Requirements based on NASA-STD-8719.29.

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Several pages will be developed as prototypes for this project. Some pages may be published in the SWEHBVD.

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01. Introduction
12. New Pages
23. Requirements
34. Other Sections
45. ToDo
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1. Introduction 

This new set of software requirements is a model based on the following documents:

  • The NASA-STD-8719.29 "NASA Technical Requirements for Human-Rating" is the basis for this new section of requirements.
  • There is a companion document "Additional NASA software technical requirements for human.docx" which breaks out the software related requirements. 

The model also contains additional support pages necessary to demonstrate the full scope of the new requirements.  

1.1 Model Pages

The pages in the current model include: 

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2. New Pages

2.1 New "C. Software Project Requirements" page

This new page has an additional section below the Chapter 5 table. This new table contains the Software Human Rated Requirements identified in the "Additional NASA software technical requirements for human.docx" document. 

New C. Project Software Requirements. It identifies all 18 of the new software requirements with 5 of them linked to new SWE pages. 

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2.2 New Topic "7.24 - Human Rated Software Requirements" 

This Topic is a paraphrasing of the document "Additional NASA software technical requirements for human.docx". All of the content from this document is in this topic except for the Italicized text which is embedded in the appropriate new SWE.

7.24 - Human Rated Software Requirements. This new topic will be added to the existing D. Topics page when it is released. 

This new topic references NASA-STD-8719.29 which is SWEREF-458. This topic: 

  • Identifies requirements that are are Software Human Rated Requirements 
  • Explains why certain requirements are NOT Software Requirements (Rational column in the table)
  • Offers other amplifications or clarifications about the Human Rated Requirements

In the new topic, ALL of the paragraphs from the standard, that are phrased like a requirement (in the form of a SHALL statement), are broken out in the Requirements tab. Only the ones identified as Software Human Rated are given SWE numbers.  Some have SWE pages built out (5 so far for this demo). 

 2.3 Full text of NASA-STD-8719.29

The full text of this document has been reproduced in NASA-STD-8719.29. As quotations are derived from it they will be child pages under the main page,


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3. Requirements

The NASA-STD-8719.29 "NASA Technical Requirements for Human-Rating" is the basis for this new section of requirements.

There is a companion document "Additional NASA software technical requirements for human.docx" which identifies the Software Human Related Requirements. 

3.1 Project Software Requirements

Requirements pages are modeled after the current SWE pages and only a few currently have contents. In total there are 18 identified as Software Human Rated. 

3.2 HR Series

The numbers for this series are built from the paragraph numbers in the STD. By keeping it as a 7 character string. all of the other macros that depend on this format for requirements can be used without the need for changes. This includes the SWEREF and reference related macros. The requirement number is the paragraph number without the decimal points and without the leading "4" ( section number). We will need to be custodians of the numbering because there is not a numbering scheme in the NASA-STD-8719.29 that will work for this project.

These requirements were derived from the document "Additional NASA software technical requirements for human.docx". Additional requirements exist on the standard and may be factored in later. SWE Titles were derived from paraphrasing the requirement. Many of the components of a SWE are found in these example SWEs. 

The table below contains links to new SWEs in the 8xx series along with the requirement statement.

SWE TitleRequirement

HR-31 - Single Failure Tolerance

4.3.1 The space system shall provide at least single failure tolerance to catastrophic events, with specific levels of failure tolerance and implementation (similar or dissimilar redundancy) derived via an integration of the design and safety analysis (required by NPR 8705.2).{inclu
HR-33 - Inadvertent Operator Action4.3.3 The space system shall be designed to tolerate inadvertent operator action (minimum of one inadvertent action), as verified by a human error analysis, without causing a catastrophic event.
HR-34 - Operator Action With Single System Failure

4.3.4 The space system shall tolerate inadvertent operator action, as described in Section 4.3.3, in the presence of any single system failure.

HR-35 - Mitigate Hazardous Behavior Of Critical Software

4.3.5 The space system shall provide the capability to mitigate the hazardous behavior of critical software where the hazardous behavior would result in a catastrophic event.

HR-36 - Detect And Annunciate Faults

4.3.6 The space system shall provide the capability to detect and annunciate faults that affect critical systems, subsystems, or crew health.

HR-37 - Fault Recovery

4.3.7 The space system shall provide the capability to isolate and recover from faults identified during system development or mission operations that would result in a catastrophic event.

HR-38 - Data Analysis

4.3.8 The space system shall provide the capability to utilize health and status data (including system performance data) of critical systems and subsystems to facilitate anomaly resolution during and after the mission.

HR-39 - Autonomous Operation

4.3.9 The crewed space system shall provide the capability for autonomous operation of system and subsystem functions which, if lost, would result in a catastrophic event.

HR-41 - Crew Operations

4.4.1 The crewed space system shall provide the capability for the crew to monitor, operate, and control the crewed space system and subsystems, where: 

  1. The capability is necessary to execute the mission; or
  2. The capability would prevent a catastrophic event; or
  3. The capability would prevent an abort.
HR-42 - Crew Override

4.4.2 The crewed space system shall provide the capability for the crew to manually override higher level software control and automation (such as automated abort initiation, configuration change, and mode change) when the transition to manual control of the system will not cause a catastrophic event.

HR-43 - Crew Control

4.4.3 The space system shall provide the capability for humans to remotely monitor, operate, and control the crewed system elements and subsystems, where:

  1. The remote capability is necessary to execute the mission; or
  2. The remote capability would prevent a catastrophic event; or
  3. The remote capability would prevent an abort.

HR-51 - Crew Flight Control

4.5.1 The crewed space system shall provide the capability for the crew to manually control the flight path and attitude of their spacecraft, with the following exception: during the atmospheric portion of Earth ascent when  structural and thermal margins have been determined to negate the benefits of manual control.

HR-61 - Crew Control Of Uncrewed Spacecraft

4.6.1 The space system shall provide the capability for the crew to monitor, operate, and control an uncrewed spacecraft during proximity operations, where:

  1. The capability is necessary to execute the mission; or
  2. The capability would prevent a catastrophic event; or
  3. The capability would prevent an abort.
HR-713 - Interface with Launch Vehicle

4.7.1.3 The crewed space system shall monitor the Earth ascent launch vehicle performance and automatically initiate an abort when an impending catastrophic failure is detected.

HR-7141 - Crew Initiate Ascent Abort Sequence

4.7.1.4.1 The space system shall provide the capability for the crew to initiate the Earth ascent abort sequence.

HR-7142 - Ground Initiate Ascent Abort Sequence

4.7.1.4.2 The space system shall provide the capability for the ground control to initiate the Earth ascent abort sequence.

HR-715 - Interface With Range Safety Destruct System

4.7.1.5 If a range safety destruct system is incorporated into the design, the space system shall automatically initiate the Earth ascent abort sequence when range safety destruct commands are received onboard, with an adequate time delay prior to destruction of the launch vehicle to allow a successful abort.

HR-72 - Autonomous Mission Abort

4.7.2 Earth Orbit Systems.  The crewed space system shall provide the capability to autonomously abort the mission from Earth orbit by targeting and performing a deorbit to a safe landing on Earth.

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4. Other Sections in SWEs

4.1 Tab 1 - Requirement

The content of this tab is well regimented. Only a few items will need to be updated: 

  • Notes - may need to be added if there are none in NASA-STD-8719.29
  • History - needs to be built 
  • Applicability across classes table - May need to be added
  • Activity - needs to be identified and added to the Activity scheme

4.2 Tab 2 - Rationale

Rational was derived from NASA-STD-8719.29 in some instances. This may needed to be updated. 

4.3 Tab 3 - Guidance

Content from NASA-STD-8719.29 was added here where appropriate. Additional guidance may need to be added. 

4.4 Tab 4 - Small Projects

Content for this tab needs to be developed. 

4.5 Tab 5 - Resources

Where appropriate, references need to be identified and added to the SWEs. 

4.6 Tab 6 - Lessons Learned

Some requirements in NASA-STD-8719.29 contain acknowledgements of Lessons Learned where the requirement would be applicable. Each of these needs to be researched and added to the SWE's tab 6 Lessons Learned. 

4.7 Tab 7 - SA

Content will be needed in this tab. 

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5. To Do

These items are to be done as a part of implementing the HR requirements. 

DescriptionItems Planned / Completed (green)

Notes

Add a SWEREF for NASA-STD-8719.29 SWEREF-458

added to HR-31

New "C. Software Project Requirements - HR" page  New C. Project Software Requirements 
Build 5 Test requirement pages

HR-31 - Single Failure Tolerance

HR-33 - Inadvertent Operator Action

HR-35 - Mitigate Hazardous Behavior Of Critical Software

HR-41 - Crew Operations

HR-51 - Crew Flight Control

All 5 exist and have a modest amount of content in them coming from NASA-STD-8719.29. 

All have been renumbered into the HR series


Turn "Additional NASA software technical requirements for human.docx" into Topic 7.24 - Human Rated Software Requirements that points to the HR requirements. New Topic 7.24 - Human Rated Software Requirements added

Added 18 HR requirement pages


Research each SWE for possible Lessons Learned

Example, para 4.7.7.3 references a Soyuz mission that fell short. A modification was made and successfully utilized on a later mission. 

Add LL to SWE tab 6 as appropriate


Build Doc pages for content developers to use in providing content. 



Add content to all new SWEs. 



Update Introduction to discuss the addition of HR requirements in NASA-STD-8719.29



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Page Editor: Tim Crumbley
NASA Official: Tim Crumbley
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