EVA-EXP-0042.pdf

EVA-CM-001 01/28/2020

EVA-EXP-0042

REVISION B

National Aeronautics and Space Administration

EFFECTIVE DATE: OCTOBER 19, 2020

EXPLORATION EVA SYSTEM

CONCEPT OF OPERATIONS

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Revision: B Document No: EVA-EXP-0042 Effective Date: October 19, 2020 Page: 2 of 175 Title: Exploration EVA System Concept of Operations

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Prepared by:

XX/David Coan, EVA Operations & Engineering Specialist

Concurred by:

XX/Lori Crocker, EVA Strategic Integration Office, Manager

Approved by:

XX/Christopher P. Hansen, EVA Office, Manager

David Coan (affiliate)

Digitally signed by David Coan (affiliate) Date: 2020.10.16 10:29:48 -05'00'

LORI

CROCKER

Digitally signed by LORI

CROCKER

Date: 2020.10.16 11:06:58 -05'00'

CHRISTOPH

ER HANSEN

Digitally signed by

CHRISTOPHER HANSEN

Date: 2020.10.19 09:19:13 -05'00'

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REVISION AND HISTORY PAGE

Revision No.

Change No. Description Release

Date

B Revision B (Reference EVA-CR-00082) New template (change in section numbers) Section 1: Updated with Artemis Program Section 2: Updated references Section 3: Added Artemis Program and phases Section 4: Consolidated information, incorporated information from EVA-EXP-0075, community work on xEVA System, the Artemis Program, Gateway, HLS, and LTV

Section 5: Minor cleanup and updates Section 6: Minor cleanup and updates Section 7: Updated per Artemis Program Section 8: Minor cleanup and updates Section 9: Minor cleanup and updates Appendices: New appendices with details and information from revision A, along with architecture information moved to annexes

10/07/2020

A Revision A (Reference CR EVA-CR-00048 dated 07/03/2019)

Section 1: Updates and clarifications Section 2: Clarifications and formatting updates Section 3: Most of section moved to EVA-EXP-0041 Section 4: Content reduced and simplified Section 5: Updates to xEVA System overview Section 6: Minor cleanup Section 7: Minor cleanup Section 8: Updated lunar details per Artemis and EVA-

EXP-0075

Section 9: Minor cleanup

07/03/2019

Baseline Baseline (per EVA-CR-00032) 12/20/2017 EVA-REF-004 Revision History

Initial Draft Preliminary Baseline 05/17/2016 Pre Baseline 07/07/2014

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TABLE OF CONTENTS

SECTION PAGE

1.0 INTRODUCTION

1.1 PURPOSE

1.2 SCOPE

1.3 CHANGE AUTHORITY/RESPONSIBILITY

2.0 DOCUMENTS

2.1 APPLICABLE DOCUMENTS

2.2 REFERENCE DOCUMENTS

3.0 EXPLORATION PROGRAM & ARCHITECTURE GOALS

3.1 RETURNING TO THE MOON

3.1.1 Space Policy Directive – 1

3.1.2 5th Meeting of the National Space Council

3.2 ARTEMIS LUNAR PROGRAM

3.2.1 Artemis Phase 1

3.2.2 Artemis Phase 2

3.3 INTO THE PROVING GROUND (AND ON TO MARS)

4.0 EXPLORATION EVA AND MISSION SYSTEMS OVERVIEW

4.1 EXPLORATION EVA OVERVIEW

4.1.1 xEVA System Definition

4.1.2 Exploration EVA System Strategy

4.1.3 Phases of Operations for xEVA System

4.1.4 Frequency and Duration of EVAs

4.1.5 EVA Tasks for Exploration Missions

4.2 XEVA SYSTEM KEY CAPABILITIES & FEATURES

4.2.1 xEVA Suit and Ancillary xEVA Equipment

4.2.2 VISE

4.2.3 xEVA Accessories

4.2.4 EVA Task Tools & Equipment

4.3 AUXILIARY SUPPORT SYSTEMS FOR XEVA

4.3.1 Navigation & Tracking

4.3.2 EVA Mission Support System

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4.4 EGRESS/INGRESS METHODS

4.5 SPACECRAFT

4.5.1 Orion

4.5.2 Gateway

4.5.3 HLS (Human Landing System)

4.6 SURFACE MOBILITY

4.6.1 Lunar Terrain Vehicle (LTV)

4.6.2 Crewed Pressurized Rovers (CPR)

5.0 CONCEPT OF OPERATIONS FOR EVA ON A SPACECRAFT

5.1 CON OPS FOR EVA ON ISS (MICROGRAVITY EVA IN LEO)

5.1.1 Demonstration of xEVA Suit (xEMU) on ISS

5.1.2 ISS Nominal Operations with xEVA Suit

5.2 CON OPS FOR EVA ON GATEWAY (MICROGRAVITY EVA IN CISLUNAR SPACE)

5.2.1 General Aspects of EVA on Gateway

5.2.2 Road-to EVA (Gateway)

5.2.3 EVA Prep & Prebreathe (Gateway)

5.2.4 EVA (Gateway)

5.2.5 Post EVA (Gateway)

6.0 CONCEPT OF OPERATIONS FOR EVA ON A SMALL NATURAL BODY

6.1 CON OPS FOR EVA ON A CAPTURED ASTEROID

6.1.1 Road-to EVA (Captured Asteroid)

6.1.2 Prep & Prebreathe on EVA Day (Captured Asteroid)

6.1.3 EVA (Captured Asteroid)

6.1.4 Post EVA (Captured Asteroid)

6.2 CON OPS FOR EVA ON A NEAR EARTH ASTEROID (NEA)

6.2.1 Road-to EVA (NEA)

6.2.2 Prep & Prebreathe on EVA Day (NEA)

6.2.3 EVA (NEA)

6.2.4 Post EVA (NEA)

6.3 CON OPS FOR EVA ON THE MOONS OF MARS

6.3.1 Road-to EVA (Moons of Mars)

6.3.2 Prep & Prebreathe for EVA (Moons of Mars)

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6.3.3 EVA (Moons of Mars)

6.3.4 Post EVA (Moons of Mars)

7.0 CONCEPT OF OPERATIONS FOR EVA ON THE MOON

7.1 SCIENCE OBJECTIVES & REGIONS OF INTEREST

7.1.1 Science Objectives for the Lunar Surface

7.1.2 General Regions of Interest

7.1.3 Lunar South Pole Region

7.2 CON OPS FOR EVA ON LUNAR SURFACE (ARTEMIS PHASE 1)

7.2.1 Preflight and Earth Launch

7.2.2 On-Orbit Operations (Crew Arrival)

7.2.3 Descent to Lunar Surface

7.2.4 Lunar Surface EVA Operations

7.2.5 Road-to EVA (Lunar)

7.2.6 Prep & Prebreathe for EVA (Lunar)

7.2.7 Egress and Setup

7.2.8 EVA Surface Operations

7.2.9 Cleanup and Ingress

7.2.10 Post EVA Operations

7.2.11 Maintenance

7.2.12 Ascent from Lunar Surface

7.2.13 On-Orbit Operations (Crew Return)

7.2.14 Design Reference EVA for Artemis III

7.3 CON OPS FOR EVA ON LUNAR SURFACE (ARTEMIS PHASE 2)

7.3.1 Sustained Mission – Short Stay

7.3.2 Sustained Missions – Extended Stay

7.3.3 Design Reference EVA for Artemis Phase 2

8.0 CONCEPT OF OPERATIONS FOR EVA ON MARS

8.1 GENERAL CONSIDERATIONS FOR MARS

8.2 CON OPS FOR EVA ON MARS

8.2.1 Road-to EVA (Mars)

8.2.2 Prep & Prebreathe for EVA (Mars)

8.2.3 EVA (Mars)

8.2.4 Post EVA (Mars)

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9.0 CONTINGENCIES & CREW RESCUE

9.1 SELF-RESCUE

9.1.1 Microgravity Self-Rescue

9.1.2 Lunar Surface Self-Rescue and Rover Rescue

9.2 INCAPACITATED CREWMEMBER RESCUE

9.2.1 Microgravity EVA Rescue

9.2.2 Partial-Gravity Surface Rescue

9.3 EMERGENCY RECOMPRESSION

9.4 CONTAMINATION

9.5 LOSS OF COMMUNICATION

9.6 LOSS OF TRANSPORTATION

9.7 RADIATION

9.8 VEHICLE CONTINGENCIES

9.8.1 Orion

9.8.2 Gateway

9.8.3 HLS

9.8.4 Pressurized Rover

APPENDIX

APPENDIX A ACRONYMS AND ABBREVIATIONS AND GLOSSARY OF TERMS

APPENDIX B OPEN WORK

APPENDIX C ADDITIONAL REFERENCES

APPENDIX D KEY FIGURES OF MERIT (FOM)

APPENDIX E NEXTSTEP APPENDIX H: HLS

APPENDIX F EVA TASKS FOR EXPLORATION MISSIONS

APPENDIX G EVA TOOLS & EQUIPMENT

APPENDIX H INFORMATICS

APPENDIX I PRE-ARTEMIS LUNAR MISSION SCENARIOS

APPENDIX J DOCUMENT TREE & INFORMATION FLOW FOR XEVA SYSTEM CON OPS

TABLE

TABLE 2.1-1: APPLICABLE DOCUMENTS LIST

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TABLE 2.2-1: REFERENCE DOCUMENT LIST

TABLE 4.2.4.1-1: TYPES OF GEOLOGY SAMPLING TOOLS

TABLE B1.0-1: TO BE DETERMINED ITEMS

TABLE B2.0-1: TO BE RESOLVED ISSUES

TABLE B3.0-1 FORWARD WORK

TABLE D-1: KEY FOMS FOR A MICROGRAVITY EVA ON ISS

TABLE D-2: KEY FOMS FOR EVA ON GATEWAY (MICROGRAVITY IN CISLUNAR

SPACE)

TABLE D-3: KEY FOMS FOR EVA FROM DEEP SPACE TRANSIT (DST) VEHICLE IN

CISLUNAR SPACE

TABLE D-4: KEY FOMS FOR EVA FROM DST VEHICLE IN TRANSIT TO/FROM MARS

TABLE D-5: KEY FOMS FOR EVA ON A CAPTURED ASTEROID

TABLE D-6: KEY FOMS FOR EVA ON A NEA

TABLE D-7: KEY FOMS FOR EVA ON THE MOONS OF MARS

TABLE D-8: KEY FOMS FOR EVA ON THE LUNAR SURFACE

TABLE D-9: KEY FOMS FOR EVA ON MARS

TABLE F-1: ENGINEERING TASKS

TABLE F-2: SCIENTIFIC TASKS

TABLE G-1: GEOLOGY SAMPLE TYPES

FIGURE

FIGURE 3.2.1-1: ARTEMIS PHASE 1

FIGURE 3.3.2-1: ARTEMIS PHASE 2

FIGURE 4.1.1-1: SYSTEMS UTILIZED TO EXECUTE EXPLORATION EVAS

FIGURE 4.1.1-2: XEVA SYSTEM SUIT CONCEPT

FIGURE 4.1.2.1-1: EXPLORATION XEVA SYSTEM CAPABILITY BOUNDARIES

FIGURE 4.1.2.1-2: XEMU CAPABILITIES

FIGURE 4.1.5-1: EMU MICRO-G EVA ON ISS (L) AND SURFACE EVA DURING APOLLO

(R)

FIGURE 4.1.5.1.3-1: CONTINGENCY BMRRM R&R ON ISS DURING US EVA 14 (L) AND

UNFORESEEN SOLAR ARRAY REPAIR DURING STS-120

FIGURE 4.1.5.1.4-1: EVA ENGINEERING TASKS FOR SURFACE OPS

FIGURE 4.1.5.2.1-1: EVA SURFACE SCIENCE OBSERVATION & DATA COLLECTION

TASKS

FIGURE 4. 4.1.5.2.1-2: EVA SCIENCE SAMPLE ACQUISITION TASKS

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FIGURE 4.2.1.1-1: XEVA SYSTEM SUIT CONCEPT

FIGURE 4.2.1.2-1: APOLLO 10 CREW TRAINING FOR LUNAR DESCENT IN SUITS .37

FIGURE 4.2.1.2.1-1: XEMU VEHICLE LOOP MODE CONFIGURATION

FIGURE 4.2.1.3-1: XEVA SUIT CONDUCTING TASKS STANDING AND KNEELING ..39

FIGURE 4.2.1.3.1.1-1: LUNAR SURFACE EVA EXCURSION RANGES

FIGURE 4.2.1.4-1: GENERAL SCIENCE REGIONS OF INTEREST FOR LUNAR

SURFACE MISSIONS

FIGURE 4.2.1.4.1-1: DUST CONTAMINATION DURING APOLLO 17

FIGURE 4.2.1.5-1: XEVA SUIT LIGHT AND VISOR NOTIONAL CONCEPTS

FIGURE 4.2.1.6-1: XEVA SUIT CAMERA NOTIONAL CONCEPT

FIGURE 4.2.4.1-1: SCIENCE SAMPLING TOOLS (RAKE)

FIGURE 4.2.4.2-1: CARRYING TOOLS ON APOLLO SUITS

FIGURE 4.4-1: EVA EGRESS/INGRESS METHODS

FIGURE 4.4.-2: SUITLOCK (REAR-ENTRY AIRLOCK) CONCEPT

FIGURE 4.5.1-1: ORION

FIGURE 4.5.2-1: GATEWAY

FIGURE 4.5.2-2: GATEWAY PHASE I

FIGURE 4.5.2-3: GATEWAY PHASE II

FIGURE 4.5.3.1-1: HLS REFERENCE CONCEPT

FIGURE 4.6.1-1: UNPRESSURIZED ROVER CONCEPT VEHICLE

FIGURE 4.6.2-1: PRESSURIZED ROVER CONCEPT

FIGURE 5.1-1: EVA OPERATIONS ON THE SPACE SHUTTLE AND SPACE STATION66

FIGURE 5.2.1-1: EVA INTERFACES SUPPORTING NOMINAL EVA CAPABILITY

FIGURE 5.2.2-1: ROAD-TO EVA REFERENCE BASED ON ISS EMU EVA

FIGURE 5.2.3-1: DAY OF EVA EXAMPLE TIMELINE BASED ON ISS EMU EVA

FIGURE 6.1.1-1: CONCEPT FOR EVA ON A CAPTURED ASTEROID

FIGURE 6.1.3-1: EVALUATING ASTEROID EVA BOOM OPERATIONS IN THE NBL AND

DURING NEEMO 20

FIGURE 6.1.3-2: ASTEROID SAMPLE COLLECTION CONCEPT (ARCM) AND

EVALUATIONS DURING NEEMO 20

FIGURE 6.1.3-3: ASTEROID SAMPLE STOWAGE CONCEPT (ARMC) AND

EVALUATIONS DURING NEEMO 20

FIGURE 6.1.3-4: BRINGING ASTEROID SAMPLE INSIDE VEHICLE

FIGURE 6.3-1: MOONS OF MARS (PHOBOS AND DEIMOS)

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FIGURE 6.3.3-1: EVALUATING SCIENCE EVA TASKS FOR PHOBOS DURING NEEMO

FIGURE 7.0-1: LUNAR EVA DURING APOLLO 16

FIGURE 7.1.2-1: POTENTIAL LUNAR SCIENCE LANDING SITES

FIGURE 7.2-1: PHASE OF XEVA OPERATIONS FOR LUNAR SURFACE MISSIONS..90

FIGURE 7.2-2: LUNAR SCIENCE EVA OPERATIONS DURING APOLLO 17

FIGURE 7.2.14-1: NOTIONAL LUNAR LANDING SITE AT CONNECTING RIDGE

FIGURE 7.2.14.1-1: NOTIONAL DESIGN REFERENCE EVA SERIES FROM EVA-EXP-

FIGURE 7.2.14.2-1: DESIGN REFERENCE EVA OUTLINE FROM EVA-EXP-0075

FIGURE 8.1-1: EVALUATING SCIENCE TEAM INTERACTION WITH MARS EVA DURING

NEEMO 20

FIGURE 8.1-2: EVALUATING MULTI-DAY CREW SELF-SCHEDULING OF EVAS

FIGURE 8.2.3.2-1: EVALUATING SCIENCE SAMPLE ACQUISITION ON MARS DURING

NEEMO 20

FIGURE 8.2.3.2-2: EVALUATING SAMPLE MARKERS NAVIGATION METHODS TO

IDENTIFY ZONES

FIGURE 9.3-1: ISS EMU CHECKLIST DCS CUFF CLASSES

FIGURE G-1: UTILIZING THE PISTOL GRIP TOOL (PGT) DURING AN ISS EVA

FIGURE G-2: POWERED AND MANUAL EVA SAMPLE ACQUISITION TOOL CONCEPTS

(CORE, CHIP, SOIL, SURFACE)

FIGURE H-1: CAPABILITY CONCEPT FOR AN AUGMENTED HEADS-UP DISPLAY

SYSTEM

FIGURE H-2: TESTING AN EVA ELECTRONIC CUFF DURING STS-69

FIGURE J-1: XEVA SYSTEM DOCUMENT TREE PER EVA-EXP-0045

FIGURE J-2: XEVA SYSTEM INFORMATION FLOW FOR THE CON OPS

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1.0 INTRODUCTION

The Exploration Extravehicular Activity (xEVA) System concept of operations (con ops) captures the National Aeronautics and Space Administration’s (NASA’s) current aims future missions to all potential Exploration destinations. This document captures the mission architectures, stakeholder expectations, and high level definitions of the capabilities and interfaces associated with the xEVA System. This includes missions to Gateway in cislunar space, the lunar surface, a redirected asteroid in cislunar space, Near Earth Asteroids (NEA), Mars’ orbit, the moons of Mars (Phobos and Deimos), and the surface of Mars. These missions, which include microgravity, milli-gravity, and partial-gravity surface EVAs, will involve a variety of engineering (maintenance, contingency, pioneering, construction) and science tasks. This document also captures information concerning vehicles and habitats with which the xEVA System will interface. The concepts of operations (con ops) detailed in this document are informed by the Artemis Program and a multitude of Exploration studies, and are also influenced by various integrated operational analog testing.

1.1 PURPOSE

This EVA Office document captures the xEVA concepts of operations for a wide range of destinations. It focuses on the lunar surface in order to support the Artemis Program, including the science goals driving the missions and the xEVA System capabilities needed to successfully complete the operations. The concepts of operations detailed in this document are intended to inform the development of the xEVA System, including the xEVA Suit, the current design solution for which is the Exploration Extravehicular Mobility Unit (xEMU), and the Vehicle Interface to Suit Equipment (VISE).

EVA-EXP-0042 describes the xEVA System operations and the tasks that will be accomplished during missions on the International Space Station (ISS), on Gateway in cislunar orbit, and on the lunar surface as part of the Artemis Phases. It also includes con ops for missions to asteroids and to Mars. This document is intended for Program concept of operations development and Exploration spacesuit suppliers. EVA-EXP-0042 provides the EVA Office standard for conducting EVA in a multitude of environments and locations, and new Programs working with the EVA Office will utilize this con ops as the basis for how EVAs will be conducted, tailored as needed to meet the objectives and goals of that Program. For spacesuit developers, this document provides the basis of what is operationally expected of the spacesuit in a given environment. If there is a conflict between EVA-EXP-0042 and other con ops involving EVA operations, EVA-EXP-0042 takes precedence. An exception is a program specific con ops tailored with support and approval by the EVA Office will take precedence over EVA-EXP-0042.

1.2 SCOPE

It is intended that the content contained in this document is to enable the development of more refined concept of operations for Exploration missions and architecture (e.g., Gateway, the Artemis Program, and the Human Landing System), for the xEVA system

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(e.g., SSP 51073), and for the subsystems (e.g. xEMU ConOps Ref#) and associated requirements (e.g. xEMU PTRS ref#) and provide the motivating/supporting rational and context for system verification.. The con ops will continue to mature as the Exploration architecture missions evolve, and this document will continuously evolve and be updated accordingly.

This document includes the information contained in EVA-EXP-0075, Exploration EVA System Concept of Operations Summary for Artemis Phase 1 Lunar Surface Mission, presented at the EVA Exploration Workshop on 18 February 2020. Results from pertinent integrated operational tests (analogs) were utilized to provide relevant data for informing concepts, flushing out capabilities, and evolving systems. Finally, the xEVA Concepts of Operations Working Group (xEVA Con Ops WG) was utilized to consolidate and finalize the high level definition of the mission architecture, capability needs, and concepts of operations associated with conducting EVA operations.

Specifically for the xEMU project, that suit is intended to have the capability to support missions from the ISS, to the lunar vicinity (on Gateway), and to the lunar surface as a key component of Artemis. The capabilities needed for that suit and associated equipment are described in Section 4.1.2, initial lunar mission parts of Section 4.2 (specifically Section

4.2.1 for the spacesuit), Section 5.1.1, and Section 7.2.

1.3 CHANGE AUTHORITY/RESPONSIBILITY

Proposed changes to this document shall be submitted by an EVA Office Change Request (CR) to the EVA Configuration Control Board (EVA CCB) for consideration and disposition.

All such requests will adhere to the EVA Office Configuration Management Change Process (EVA-PLN-012).

The appropriate NASA Office of Primary Responsibility (OPR) identified for this document is EVA.

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2.0 DOCUMENTS

2.1 APPLICABLE DOCUMENTS

The following documents include specifications, models, standards, guidelines, handbooks, and other special publications. The documents listed in this paragraph are applicable to the extent specified herein.

TABLE 2.1-1: APPLICABLE DOCUMENTS LIST

Document Number

Document Revision/Release

Date Document Title Applicability

Alternative Documents (allowed/not allowed) JSC-48538 07/16/2007 ISS EVA Systems Checklist

SSP 51073 /

EVA-RD-001

B 04/10/2020 xEVA Suit Systems Requirements Document

SSP 51080 /

EVA-EXP-

Baseline 12/04/2018 xEMU-ISS Interface Requirements Control Document

Baseline 04/04/2018

EVA Airlocks and Alternative Ingress/Egress Methods

Baseline 606/05/2018

EVA-ISS Interface Definition Document (IDD)

B 07/31/2020

Exploration EVA System Technical Standards

Baseline 09/12/2018

Compatibility

A 11/29/2017

Exploration EVA System Destination Environments Specifications

Baseline 12/18/2018

Architecture Description

Baseline 10/25/2018

NASA Project Management Plan for the Exploration EVA System

TBD-2.1-014 Exploration EVA Suit-Airlock Interfaces, Ops Con and Objectives

2.2 REFERENCE DOCUMENTS

The following documents contain supplemental information to guide the user in the application of this document. Additional reference documents utilized to develop the xEVA con ops are listed in an appendix.

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TABLE 2.2-1: REFERENCE DOCUMENT LIST

Document Number Document Revision Document Title

EVA-EXP-0075 Baseline 03/17/2020

Exploration EVA System Concept of Operations Summary for Artemis Phase 1 Lunar Surface Mission

EVA-PLN-012 A

10/02/2019

EVA Office Configuration and Data Management Plan

HLS-CONOPS-001 Baseline (draft) 05/21/2020

Human Landing System (HLS) Program Concept of Operations – Initial Phase

Artemis-CONOPS-

Draft Artemis Concept of Operations

GP 10027 Baseline 05/07/2020

Gateway Concept of Operations https://www.nasa.go v/sites/default/files/a toms/files/a_sustain ed_lunar_presence_ nspc_report4220fina l.pdf

04/02/2020 NASA’s Plan for Sustained Lunar Exploration and Development https://www.nasa.go v/sites/default/files/a toms/files/artemis_pl an-20200921.pdf

09/21/2020 Artemis Science Plan

HEOMD-005 Concept of Operations HEOMD-006 Exploration Utilization Plan AES-50002 Baseline Artemis Sustained Lunar Exploration Requirements AES-50010 Baseline Advanced Exploration Systems Lunar Terrain Vehicle (LTV)

Concept of Operations https://www.nasa.gov/sites/default/files/atoms/files/a_sustained_lunar_presence_nspc_report4220final.pdf https://www.nasa.gov/sites/default/files/atoms/files/a_sustained_lunar_presence_nspc_report4220final.pdf https://www.nasa.gov/sites/default/files/atoms/files/a_sustained_lunar_presence_nspc_report4220final.pdf https://www.nasa.gov/sites/default/files/atoms/files/a_sustained_lunar_presence_nspc_report4220final.pdf https://www.nasa.gov/sites/default/files/atoms/files/a_sustained_lunar_presence_nspc_report4220final.pdf https://www.nasa.gov/sites/default/files/atoms/files/a_sustained_lunar_presence_nspc_report4220final.pdf https://www.nasa.gov/sites/default/files/atoms/files/artemis_plan-20200921.pdf https://www.nasa.gov/sites/default/files/atoms/files/artemis_plan-20200921.pdf https://www.nasa.gov/sites/default/files/atoms/files/artemis_plan-20200921.pdf https://www.nasa.gov/sites/default/files/atoms/files/artemis_plan-20200921.pdf

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3.0 EXPLORATION PROGRAM & ARCHITECTURE GOALS

The United States (U.S.) Executive Branch and the NASA administration have released several policies and documents that outline returning to the moon and eventually landing on Mars. Those documents make up the basis for the xEVA con ops.

3.1 RETURNING TO THE MOON

Through Space Policy Directive – 1 and the 5th Meeting of the National Space Council, the United States set in motion plans to return humans to the surface of the moon.

3.1.1 Space Policy Directive – 1

On 11 December 2017, Space Policy Directive – 1 was updated to redirect the nation’s spaceflight efforts to returning humans to the lunar surface. In part, this policy states:

“Beginning with missions beyond low-Earth orbit, the United States will lead the return of humans to the Moon for long-term exploration and utilization, followed by human missions to Mars and other destinations.”

3.1.2 5th Meeting of the National Space Council

On 26 March 2019, discussions at the National Space Council provided further direction and details on the lunar surface mission plans. In part, it was stated:

• “Fifty years ago, “one small step for man” became “one giant leap for mankind.”

But now it’s come the time for us to make the next “giant leap” and return American astronauts to the Moon, establish a permanent base there, and develop the technologies to take American astronauts to Mars and beyond.”

• “…it is the stated policy of this administration and the United States of America to return American astronauts to the Moon within the next five years.”

• “And today, the National Space Council will recommend that when the first American astronauts return to the lunar surface, that they will take their first steps on the Moon’s South Pole.”

3.2 ARTEMIS LUNAR PROGRAM

In response to the new Executive Branch direction, NASA implemented the Artemis Program.

3.2.1 Artemis Phase 1

Per “Forward to the Moon: NASA’s Strategic Plan for Human Exploration”, 4 Sept 2019, Artemis Phase 1 builds up to the first crewed mission to the lunar surface.

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FIGURE 3.2.1-1: ARTEMIS PHASE 1

3.2.2 Artemis Phase 2

Per “Forward to the Moon: NASA’s Strategic Plan for Human Exploration”, 4 Sept 2019, Artemis Phase 2 continues the lunar surface missions into sustainable capabilities and exploration.

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FIGURE 3.3.2-1: ARTEMIS PHASE 2

3.3 INTO THE PROVING GROUND (AND ON TO MARS)

Prior to Artemis, the Human Exploration and Operations Mission Directorate (HEOMD) released several Level 1 documents which lay out objectives, concept of operations, and utilization plans pertaining to EVA through crewed missions to Mars.

Per the paper entitled ISS, SLS, Orion: Into The Proving Ground presented by the Human Exploration and Operations (HEO) Associate Administrator at the International Astronautical Congress in Adelaide, Australia in September 2017, the current long term goal for NASA is a crewed mission to the Martian system by 2033 with a human landing later in the decade. This led to the release of HEOMD-001 Human Exploration and Operations Exploration Objectives document, and the high level description of the phases of exploration.

The goal of landing humans on the surface of Mars will be accomplished through five phases. Phase 0, involves continuing to use the ISS for research and as a testbed. Per the IAC 2017 paper, the remaining phases are as follows:

In Phase 1, NASA will use the Space Launch System (SLS) and the Orion capsule in the early and mid-2020s to deploy a Deep Space Gateway in cislunar space, comprising a habitation and in-space propulsion capability. In-space power and propulsion, including solar electric propulsion, and deep space habitation are central to future human exploration. Development and deployment of these capabilities will be a focus of the early-to-mid 2020s. The Gateway provides a space infrastructure

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Phase 2, in the mid-to-late 2020s, will see NASA using the SLS, Orion, and the Gateway to outfit the Deep Space Transport, which will be used to fly crews to the Martian system in the 2030s. The Deep Space Transport will be launched without fuel and supplies in single SLS launch. The fuel, supplies, and outfitting will occur over a series of SLS and Orion missions. The Deep Space Transport can benefit from the avionics and computer systems being developed for Orion. The Transport represents not only the realization of a robust habitation capability that will keep crews healthy on two-year Mars missions, but also the development of a reliable propulsion system that will be used to fly crews safely across interplanetary distances, and then back to the Earth-Moon system. The Deep Space Transport will be reusable for multiple missions and can be maintained at the Gateway. Phase 2 will culminate in a crewed one-year shakedown cruise or verification mission aboard the Deep Space Transport in cislunar space to validate its readiness to conduct missions beyond the Earth-Moon system. At this point, we will have the knowledge and the infrastructure in place for the voyage to the Martian system.

In Phase 3, NASA will conduct humanity’s first missions to another planet, with the initial crewed flight of the Deep Space Transport to the Martian system in 2033, and a potential rendezvous with the Martian moon Phobos. Astronauts will thus gain experience with interplanetary spaceflight and operations, and will fully utilize the cislunar infrastructure that has been developed to support such missions.

During the decade of the 2030s and beyond, in Phase 4 NASA will develop and deploy the systems to land cargo and crews on Mars, sustain crews on the surface, and return them safely to Martian orbit, where they will re-board the Deep Space Transport for the journey back to the Deep Space Gateway, and then home to Earth.

The main Objective Category pertaining to EVA is working in space. Deep space operations focus on providing capabilities in the areas of EVA, staging, logistics, human-robotic integration, and autonomous operations. Objectives for phases 0 and 1 include:

• Phase 0: P0-04 Demonstrate in-space exploration class EVA technologies

• Phase 1: P1-13 Validate ability to conduct EVA in deep space

HEOMD-005, Concept of Operations, includes a description of Gateway (further detailed in a later section of this document) which includes an airlock capability to enable EVAs.

Each of the Gateway elements will be designed to not require on-orbit EVA maintenance but will provide EVA translation paths in order to accommodate contingency EVAs or future utilization. The Airlock Module will provide secondary ingress capability to allow EVA crewmembers to safely ingress the stack in the event of a contingency without causing the depressurization of critical stack elements such as a habitat.

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HEOMD-006, Exploration Utilization Plan, also includes near term planned EVA technology demonstrations on ISS and xEVA providing for exploration of deep space destinations/environments and contingency EVAs during transit.

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4.0 EXPLORATION EVA AND MISSION SYSTEMS OVERVIEW

A multitude of mission systems are required in order to successfully execute Exploration missions and the EVA operations included in those missions.

4.1 EXPLORATION EVA OVERVIEW

The following subsections provide an overview of the xEVA System and other systems/vehicles that will be utilized during Exploration missions.

4.1.1 xEVA System Definition

The xEVA System works in conjunction with the larger mission architecture and systems to conduct EVA operations at Exploration destinations. Figure 4.1.1-1: Systems Utilized to Execute Exploration EVAs shows the constituent elements that comprise the xEVA Mission System. There are elements that exist at the mission destination (and/or leveraged in transit from Earth to that particular mission destination) as well as elements that remain on Earth. While the details of each of these elements will differ between mission types, the fact remains that there will remain a connection to some extent between crew/local elements and Earth.

FIGURE 4.1.1-1: SYSTEMS UTILIZED TO EXECUTE EXPLORATION EVAS

As NASA aims to shift from an Earth-reliant mindset to one that is independent of Earth, what will fundamentally drive the success of this shift is how the concepts of operation for a particular mission are established. In other words, who (crew and their local systems or Earth-based personnel) will be responsible for what to satisfy mission objectives. The inclusion of more advanced systems that afford crew the ability to become more self-reliant will become critical for mission success.

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The xEVA System allows crewmembers to conduct excursions outside a habitable vehicle in order to perform exploration, science, construction, servicing, and repair operations.

The xEVA System includes the following elements:

• Spacesuit (xEVA Suit)

• Vehicle Interface to Suit Equipment (VISE)

• Flight Support Equipment (FSE)

• Tools and equipment necessary to perform EVA tasks

The xEVA Suit (e.g., xEMU) provides life support, environmental protection, and communications capability to the crewmember while allowing sufficient mobility to perform dexterous EVA tasks. The primary functions of the xEVA Suit are to provide a habitable, anthropomorphic, pressurized environment that allows crewmembers to perform work outside of the spacecraft or habitat in hazardous external conditions. The habitable environment is maintained by using suit components such as an outer pressure garment to maintain survivable pressure on the crewmember’s body, including boots and gloves, a helmet that allows suitable visibility for tasks, a thermal micrometeoroid garment to protect against thermal extremes and micrometeoroid impacts, a garment to prevent overheating in the suit, and a life support system to provide the necessary consumables (oxygen, water, and power) and remove carbon dioxide and contaminants.

FIGURE 4.1.1-2: XEVA SYSTEM SUIT CONCEPT

The VISE provides the interfaces necessary between the xEVA suit and the host vehicle.

These interfaces will enable recharge of consumables and checkout the xEVA equipment.

VISE performs that functions that are currently done on ISS by the Exploration Servicing, Effective Date: October 19, 2020 Page: 22 of 175 Title: Exploration EVA System Concept of Operations

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Performance and Checkout Equipment (SPCE). At a high level, VISE can supply various consumables or resources used by xEMU, but also includes physical structures used to support/restrain the suit. VISE core functions are broken down into the following:

• Power and Data Communication

• Battery Charging

• Suit Loop Ventilation

• Vacuum Access

• High Pressure O2

• Cooling H2O

• xEMU Don/Doff Support

• HLS Descent/Ascent Crew Restraint

The FSE includes the additional equipment and ancillary hardware to support xEVA operations, such as the xEVA suit umbilicals.

The xEVA Tools will interface with a suited crewmember to enable a range of specialized tasks. These include both tools for engineering tasks on vehicles and infrastructure, and tools for science.

The xEVA System will enable and help accomplish the Exploration goals for lunar surface missions, including science.

The remaining elements that support the mission system include:

• Assets could include the addition engineered devices leverage by the mission such as rover vehicles, robotic assistants, and engineering packages

• Additional crewmembers who remain inside spacecraft, known as intravehicular crew, are also another important element of the xEVA Mission System.

• Spacecraft are an obvious component of a mission but must be considered in the context of supporting xEVA which will require interactions with these other identified elements.

• Finally, remote support consists of the entire enterprise of people and technologies that remain on Earth and support the mission objectives remotely. For the entire history of US EVA, ground-based support have play an integral and mission dependent role in successful EVA operations.

4.1.2 Exploration EVA System Strategy

While there is a wide array of possible and feasible variations across the spectrum of conceptual human spaceflight architectures, there exists a limited set of overarching destination classes. For EVA, these destination classes are defined as follows:

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• EVA on a Spacecraft (Micro-Gravity on an Engineered Surface)

• EVA on a Small Natural Body (Milli-Gravity on an Asteroid or Moons of Mars)

• EVA on the Moon (Partial-Gravity Planetary Surface in a Vacuum)

• EVA on Mars (Partial-Gravity Planetary Surface in a Partial Atmosphere)

When considered in abstract terms, all human spaceflight EVAs would be conducted within the context of one or a combination of these destination classes. For example: EVA tasks supporting construction of a multi-element spacecraft in Low Earth Orbit (LEO) (such as Mir or ISS) or EVA servicing, maintenance or repair of satellites or launch/entry spacecraft are all particular activities conducted by an EVA System designed to operate in micro-gravity on engineered objects built by humans (spacecraft or habitat), within a vacuum environment. Similarly, the particular details about EVA environments for specific destinations will vary, especially parameters like thermal and radiation, but these too may be enveloped.

Similarly, it is recognizable that although there are large numbers of NEAs and Near Earth Objects (NEO) that may at some point be accessible to human spaceflight missions, in general terms an EVA System designed to conduct activities on or immediately near the surface of a NEA (the “natural” surface) is simply an EVA System capable of performing tasks in milli-gravity within a vacuum environment and withstand intentional or inadvertent contact with material/debris not configured by human hands. Thus, despite the varying chemistries and compositions of the wide array of NEAs, an EVA System compatible with activities on a NEA would consider particular items such as abrasion, sharp edges, dust, and incidental contact temperatures. Instead, EVA activities would utilize varying amounts of engineered crew aids and drive the design of the EVA System, along with operational procedures, to accommodate the reality that the natural surface is a source of potential hazards. This logic is extendable to a NEA and to the Moons of Mars, which may ultimately be shown to be relatively large captured asteroids. Thus, though Phobos and Deimos are massive enough to provide milli-gravity level g-values of concern for spacecraft, the fundamental nature of EVAs done on them is still classifiable as small natural bodies within a vacuum environment with as far as the EVA crewmember is concerned, there is insufficient gravity to provide ground reaction force, though that milli-gravity level may increase the likelihood of contact with the surface such that it is not considered micro-gravity.

The remaining two destination classes must acknowledge a common theme: any other EVA operation must be considered as occurring on a body so massive that it possesses a non-trivial gravitational field, i.e. Earth’s Moon and Mars. Though their specific g-values differ by meaningful amounts when it comes to the resulting on-back mass experienced by the EVA crewmember, they are common in that the nature of EVA activities and tasks are significantly different than in microgravity or milli-gravity. Next, these two destinations each possess their own particular natural surface characteristics which will lead to potentially different concerns for abrasion, sharp edge tolerance, dust mitigation, chemical compatibility, planetary protection, etc. However, many of these concerns are similar between the Earth’s Moon and Mars, and the particular design solutions may be driven

Effective Date: October 19, 2020 Page: 24 of 175 just as much by human choices such as EVA frequency, duration, and total quantity of EVA as it is the singular interaction with the natural surface and environment. The difference in gravity levels between the Moon and Mars is significant. Thus, at a destination class level, the biggest differentiator between the two partial-gravity destinations is the g-value, the specific geo-technical properties of the surface, contamination concerns, thermal environment, and the atmosphere or lack thereof.

Details of the xEVA System architecture are in EVA-EXP-0041, xEVA System Architecture Description.

4.1.2.1 xEMU and mEMU

The current design concepts for the xEVA System suit are the xEMU and follow-on Mars Extravehicular Mobility Unit (mEMU). The xEVA System will be capable of operating anywhere in the range from the Venus halo orbit to the asteroid belt, and from microgravity environments to the planetary surface of Mars.

FIGURE 4.1.2.1-1: EXPLORATION XEVA SYSTEM CAPABILITY BOUNDARIES

The xEMU will be a fully outfitted deep space exploration suit that will be utilized in LEO, cislunar space (on Gateway), and possibly Mars orbit, along with transit between the two, in addition to the lunar surface as a key element of Artemis. The xEMU will utilize a lower torso assembly that allows for ambulation on the lunar surface, performance of tasks in a non-neutral posture (e.g., kneeling, squatting, bending, stooping, sitting, lying, crawling, Effective Date: October 19, 2020 Page: 25 of 175 etc.), and recovery from the non-neutral positions. It will include features such as dust tolerance and informatics. The mEMU will incorporate some aspects of the xEMU, but will be modified for operations on the surface of Mars and the different environment encountered there.

The future xEVA Suits will have the capabilities listed in Section 4.2 (specifically Section

4.2.1 for the spacesuit), including (but not limited to) increased mobility & surface ambulation (including kneeling), enhanced consumables capabilities beyond the current EMU, operability at higher and variable suit pressures, advanced integrated informatics, compatibility with a rear-entry airlock (depending on the final mission architecture and programmatic phase), and the ability to attach and transport tools in both microgravity and surface environments.

FIGURE 4.1.2.1-2: XEMU CAPABILITIES

4.1.2.2 Single Suit Architecture

In order to save on mass and conserve volume, the xEVA Program is examining utilizing a single suit system architecture for Human Landing System (HLS) operations during dynamic flight phases on descent, EVA, and dynamic phases during ascent.

The Orion Crew Survival System (OCSS) Earth Launch Entry Abort (LEA) suit will be used during launch from Earth and Earth landing, but will not be used for the lunar portions of the HLS missions. With the single suit architecture concept, the xEMU would be utilized for lunar descent/ascent in Vehicle-Loop Mode (VLM) and on the surface in EVA mode.

This means it will have both the capability to be pressurized via the VLM umbilical, without the Exploration Portable Life Support System (xPLSS) backpack during any required

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xEMU suit checkout will be done in the HLS, prior to lunar descent. The HLS will accommodate volume and equipment to stow, assemble the suits, don/doff the suits, and support on-orbit fit checks and xEMU checkout prior to descent. After checking out each xEMU, the crew will then reconfigure the suit for lunar descent by removing the suits rear-entry Hard Upper Torso (HUT) hatch and xPLSS from the Exploration Pressure Garment System (xPGS) and replacing it with a HUT hatch designed for VLM umbilical operations.

The xPLSS will be stowed for lunar descent. Upon landing the crew will then reconfigure their suits to EVA mode with the xPLSS attached. If the xPLSS will be left on the lunar surface for mass savings, the xPLSS and HUT hatch will be removed and the xEMU will be reconfigured to VLM mode for lunar ascent.

See Section 4.2.1.3.1 for further details on the single suit configurations.

4.1.3 Phases of Operations for xEVA System

Operations of the xEVA System are separated into the following phases:

1. Preflight Testing, Processing, and Training

• Ground operations including manufacturing and acceptance testing, fleet and mission-specific sizing

• Crew training on the xEVA system and the mission

• Mission planning (including environmental constraints)

2. Earth Launch

• Launch stowage and logistics prepare the hardware for launch and configuration for transportation to host vehicle

3. Suit Assembly & Checkout

• On-Orbit Suit Assembly - Operations to assemble the components of the xEVA Suit in preparation for checkout and use

• Full System Checkout - Operations describing the comprehensive checkout and evaluation of suit systems done prior to first use and after reassembly following a reconfiguration or a period of quiescent stowage

• On-Orbit Fit Verification - The process of ensuring a good fit for the planned crewmember including necessary adjustments

4. Suited Dynamic Flight Events (traveling to destination)

• Phases of the mission associated with dynamic vehicle flight and higher risk times

• Includes planetary descent, planetary ascent, undocking, and certain orbital maneuver burns

• Prebreathe for initiation of saturation (if required, dependent on lander atmosphere)

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• xEMU System is utilized in VLM

5. Prep for Operations (Road-to EVA)

• The "road-to EVA" is a comprehensive list of all the activities that occur before and up to the day prior to the start of a planned series of EVAs

• Typical activities include:

o Suit assembly or reconfiguration o Suit checkout o Fit verification o Consumables recharge (O2, H2O, etc.)

o Battery recharging o Liquid Cooling Ventilation Garment (LCVG) fill (if required) o Airlock configuration o Tools and task equipment configuration o Filling and installing drink bags in suit o Preparation of biomedical and radiation monitoring equipment o Configuration of communication system o Timeline review o Briefings from MCC and the Science Team o Uploading of data into the informatics system (as applicable)

6. Pre EVA Operations (Prep & Prebreathe)

• On the day of the EVA, the crewmembers begin final prep activities and the prebreathe protocol (as applicable)

• General day-of-EVA activities include, but aren’t limited to, the following:

o EVA prep – activities which occur the day of a planned EVA, just prior to donning the xEVA Suit for EVA o Configure vehicle and suit communication o Verify the appropriate equipment is in the airlock before isolating the module o Activate the Carbon Dioxide (CO2) removal system (if applicable) o Prepare for mask prebreathe (if applicable) o Power up the xEVA Suits and verify system functionality, and configure for suit donning o Verify xEVA Suit communication and data with IV and/or MCC o IVA crew performs any remaining airlock configuration tasks (if applicable) o Suit Donning - Operations that occur in the xEVA Suit, but prior to disconnecting from the umbilical tied to host vehicle resources o xEVA Suit manned checkout o Depress to 10.2 psia (if applicable) o o Mask prebreathe (if required) o Donning of suits o In-suit communication and leak checks o Prebreathe protocol – Prescribed prebreathe period in order to decrease the risk of Decompression Sickness (DCS)

Effective Date: October 19, 2020 Page: 28 of 175 o Depress to 10.2 psia (if applicable) o Mask prebreathe (if required) o Purge nitrogen o In-suit prebreathe on umbilical

7. EVA Operations

• Once the prep and prebreathe procedures are completed, the EVA crew will depress the airlock, switch over to suit systems, egress, and begin their tasks

• The “EVA” phase begins when the spacesuit is switched from the vehicle provided power source to internal suit power (batteries), and officially ends when repressurization has begun after ingress

8. Post EVA Operations

• Post EVA operations commence with reconnection to umbilical and airlock repress; and include doffing the xEVA Suit, servicing, disassembly, and stowage

• Consumables are recharged

9. Maintenance

• Periodic maintenance of the suits may be required, in addition to changing out some of the more consumable aspects, such as the gloves

10. Departure Prep & Quiescent Stowage

• Quiescent stowage refers to both the period of time EVA hardware is pre-dispositioned at a destination prior to human interaction and the period between crewed presence at the destination

• Prior to crew departure from the destination, hardware that is to be reused and not returned to Earth for refurbishment will be prepared for quiescent stowage, where the hardware will not be accessed by crewmembers or remotely actuated from the ground for up to three years

• Suit reconfiguration (if xEMU is needed in VLM for ascent)

11. Suited Dynamic Flight Events (leaving destination)

• Phases of the mission associated with dynamic vehicle flight and higher risk times

• Includes planetary ascent, certain orbital maneuver burns, and docking

• xEMU System is utilized in VLM

12. Post Docking Operations

• Disassemble xEVA suit for long term stowage in Gateway or leave in lander for disposal

• Transfer samples and returning xEVA hardware to Gateway and Orion

13. Post Flight

• Post-flight testing consists of flight hardware returned from orbit for examination of system and component function, health and life

• Evaluations include failure investigations

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• A thorough set of lessons learned, anomaly reports, and failure investigation reports will lead to action plans to improve the xEVA system design, processes, team communication, training, procedures, etc.

• This may include discarding and/or returning the xEVA Suit for ground processing.

4.1.4 Frequency and Duration of EVAs

The xEVA suit will support EVAs of up to 8 hours in duration (6±2 hours). How long EVAs are and at what frequency they are conducted will depend on the destination, phase, mission needs, and vehicle capabilities.

4.1.4.1 ISS EVAs

EVAs conducted on ISS will be the same duration and frequency of those that are currently done utilizing the EMU. Typically, EVAs on ISS are planned for 6.5 hours, but have frequently exceeded 7 hours, and on occasion been over 8 hours in duration.

4.1.4.2 Gateway EVAs

EVAs on Gateway will be treated similar to EVAs conducted on ISS in terms of duration.

4.1.4.3 Lunar Surface EVAs

EVAs on the lunar surface will vary according to lander capabilities, surface assets, and program phase. EVAs will be between 4 and 8 hours in length (6±2 hours). The duration will also take into account a number of factors, such as lighting and the time of year.

During the Apollo missions, the crew conducting EVAs ranging from two hours 32 minutes to seven hours 37 minutes. Out of the 14 EVAs conducted on the lunar surface, six of those were over seven hours long.

4.1.4.3.1 Artemis Phase 1 (Artemis III & IV Missions)

EVAs on the lunar surface will vary according to lander capabilities, surface assets, and program phase. EVAs will be between 4 and 8 hours in length (6±2 hours). Artemis III will have between 2 and 5 EVAs. A supplemental EVA may be allocated to dispose of trash and equipment not being brought back up from the surface, and may or may not be executed on umbilical (in VLM).

4.1.4.3.2 Artemis Phase 2 (Sustained Missions)

For Rover and EVA ops during a seven to fourteen-day short stay mission, the crew will have the capability to perform daily 8-hour EVAs in order to take advantage of the short period on the surface. Crewmembers will conduct the EVAs paired together to maximize boots on the ground time and for safety. However, there may be a rest day after three or four days of EVA, depending on the duration of the EVAs.

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For Rover and EVA ops during a 42-day mission, operations will differ between lunar day and lunar night. During lunar day, EVAs will be conducted three to four days per week and be two to eight hours in duration (hour for egress/ingress and 1.5 - 7.5 hours of tasks) with one to two per day. EVAs may extend an additional hour for emergency and off-nominal situations.

For days involving two EVA excursions per day, the EVAs will be treated as if a single EVA is conducted in two parts, and therefore the suit consumables won’t be required to be recharged between excursions (though some will be recharged simply by plugging in the umbilical, such as O2). The total amount of planned EVA Phased Elapsed Time (PET) time within a crew wake period will stay within the constraints of a single 8-hour EVA.