Report of the MEPAG Mars Human Precursor Science Steering Group Technology Demonstration and Infrastructure Emplacement (TI) Sub-Group Hinners, N.W. (Consultant),

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Presentation transcript:

Report of the MEPAG Mars Human Precursor Science Steering Group Technology Demonstration and Infrastructure Emplacement (TI) Sub-Group Hinners, N.W. (Consultant), Braun, R.D. (Georgia Tech), Joosten, K.B. (JSC), Kohlhase, C.E. (Consultant), and Powell, R.W. (LaRC) July 5, 2005

2 Citation and Clearance Recommended Bibliographic Citation Hinners, N.W., Braun, R.D., Joosten, K.B., Kohlhase, C.E., and Powell, R.W., (2005), Report of the MEPAG Mars Human Precursor Science Steering Group Technology Demonstration and Infrastructure Emplacement (TI) Sub-Group, 24 p. document posted July, 2005 by the Mars Exploration Program Analysis Group (MEPAG) at Report Clearance This report ahs been cleared by the JPL Document Review Services for public release, presentation and/or printing in the open literature. The clearance is CL# and is valid for U.S. and foreign release.

3 The Mars Human Precursor Science Steering Group was chartered on behalf of MEPAG to: 1.Identify the activities that should be performed by human precursor robotic missions for the purpose of reducing cost and/or risk of human exploration missions 2.For measurement-related activities (Measurement Sub-Group – see An Analysis of the Precursor Measurements of Mars Needed to Reduce the Risk of the First Human Mission to Mars at ): a)Identify and justify new measurements that can be acquired by robotic missions to Mars that would contribute to the overall cost or risk reduction objective. Where possible, include precision and accuracy. b)Establish preferred / required sequential relationships for measurement sets, etc. c)Suggest the number of distinct sites needed for each of the measurements in order to achieve cost and risk reduction as well as the necessary characteristics of the different sites. d)Prioritize the measurement options. MHP SSG Charter

4 3.For technology demonstrations and infrastructure (TI Sub-Group, this report): a)Identify technology flight demonstrations needing to be performed on Mars to reduce risk to human flight systems b)Prioritize technology demonstrations and infrastructure and suggest preferred / required sequential relationships MHP SSG Charter, Cont.

5 Technology & Infrastructure Sub-Group Membership Transit Sub-Team Atmosphere Sub-Team Surface Sub-Team

6 A Full Program of Preparing for a Human Mission(s) to Mars Needs to Consider the Following Components: Flight Missions to Mars –Measurements of the Martian Environment. –Technology Demos/Infrastructure Emplacement Missions to the Moon Laboratory, Field, and Flight test program on Earth Flight Missions in/to Earth Orbit Preparing for Human Exploration The Context The full job The TI Sub-Group Also Identified Demonstrations That Should Be Done on Earth, in Earth Orbit or on the Moon FOCUSFOCUS

7 ASSUME: A series of Mars robotic precursor missions prior to human exploration. It is not yet known whether launches in every opportunity are justified, so this should not be assumed. The first dedicated robotic precursor mission is scheduled for flight in the 2011 launch opportunity, and that the first human mission is scheduled for approximately A series of robotic precursor missions will be designed to reduce risk/cost in the first human mission. Assume that there will be subsequent missions which may build upon the first. A separate sequence of Mars missions, with a primary objective of robotic scientific exploration, will be carried out in addition to the human precursor sequence. Assume that the infrastructure associated with the science missions (e.g. the telecommunications infrastructure) is available for use by the human precursor missions. The 2030 mission and all of the precursor missions are funded by NASA without contributions from international partners. General TI Sub-Group Study Programmatic Assumptions

8 TI Prioritization Criteria The Technology is Likely Required to Significantly Reduce Risk and/or Cost of Human Exploration to an Acceptable (Affordable?) Level Venue: The Importance that the Technology Demonstration be Best Performed (Technical Benefit vs Cost) on a Mars Flight 1.At or In Transit to Mars 2.On the Moon 3.In Earth Orbit 4.On Earth Evaluate All Venues to Assure Completeness & Assessment of Cost/Benefit Priorities Separately Evaluated Within Time Phases Early: Influence Major Architecture Decisions (pre-Phase A) [2011 – 2016] Mid: Influence Mission & Flight Systems Design [2018 – 2022] Late: Operations Preparation Phase [2024 – 2028] Four Priority Categories: VH, H, M, L at Sub-Team Level COSTCOST DATADATA The Increasing Cost and Decreasing Data Acquisition Opportunities Favor non-Mars Venues

9 TI Working Approach Initiated Work at MHP SSG Workshop held in Monrovia, CA August 3 – 4, 2004 –The TI Sub-Group Was Divided Into Three Mission Phase Sub-Teams: Each Has Unique and Separable Functions and Thus Requirements Transit [T]: To and From Mars Atmosphere [A]: Mars Entry, Descent and Landing, Ascent Surface [S] Mission Phase Sub-Teams Worked Independently from Aug. 5 to Sept. 16, 2004 Primarily by and Telecons –Template and Refined Groundrules Defined and Distributed –Common Prioritization Criteria Defined and Distributed –All Work Was Captured in Template Form Facilitated Common Baseline for Prioritization Forced a Focus on Objective Criteria A TI Integration Meeting Was Held September 16, 2004 at JPL –Sub-Team Input Ranked in Priority Groups 1 – 3 (No Sub-Prioritization) –Only Highest Priority “at Mars” Items are Included in MEPAG IVB Goals There Are Many Additional Items Captured in Templates The TI Sub-Group Priorities Were Provided as Input to Testbed Mission Architecture Studies by Frank Jordan, JPL

10 Topic Mission Phase Identifier: Transit, Atmosphere or Surface Requirement Statement Rationale – Source of the Requirement with Description of Risk or Cost Reduction or Infrastructure Implication TRL Level of Development/Technology – TRL 1 – 9 Scale Priority Ranking with Justification – Very High, High, Medium, Low Where, with Justification – At or In Transit to Mars, Moon, Earth Orbit, Earth When, with Justification – Early ( ), Mid ( ), Late ( ), Anytime Clarifying Comments Evaluation Template

11 Systems Level Technology Template:70 deg sphere-cone aerocapture Demonstrate a representative end-to-end aerocapture system at Mars using the Viking-type aeroshell design. System is comprised of approach navigation, hypersonic atmospheric entry and exit, periapsis raise maneuver, and final orbit adjust. The target orbit would be that representative for a human mission to Mars. The atmospheric flight portion and periapsis raise maneuver would be autonomous. If funding allows, this could be followed by an hypersonic entry to prove viability of multiple- use TPS (See component technologies), thermal management, etc. Additional funding would allow a pinpoint landing demonstration. (See component technologies) The objective of this demonstration is to validate aerocapture as a viable capability for the Exploration Initiative. This capability provides significant performance advantages and is required for the architectures currently proposed by the exploration initiative. NASA system studies, and CNES project studies have all shown that aerocapture significantly reduces the entry mass, and thus reduces the launch mass requirements, the infrastructure required, and the total cost. However, this capability has never been demonstrated in-flight. The NASA Aeroassist Flight Experiment (1980’s), the original 2001 NASA Mars Orbiter mission, and the CNES 2005 orbiter mission all were to use aerocapture. All of these projects were canceled before launch, but none had uncovered any technical issue that needed to be resolved before aerocapture could be used. Because the objective of the Mars Precursors is to validate the technologies required for human exploration, aerocapture must be performed at Mars to capture the aerothermodynamic and atmospheric characteristics, the proper dynamics. Priority & Justification Where & Justification When & Justification Comments This is a cornerstone of the exploration initiative and this fundamental capability must be demonstrated early to validate the exploration initiative architecture. System depends on Mars approach nav, spacecraft dynamics [as influenced by Mars dynamics- delete], Mars atmosphere mean density characteristics (e.g. scale height) and density perturbations. An Earth test would be valuable but not sufficient Because this is a cornerstone, this must be done early. If aerocapture fails, the architectural ramifications are large. The technologies required for aerocapture using a Viking-shape aeroshell to a low Mars orbit are all at TRL=5 or higher. The recommendation would be to fly this proven shape and demonstrate aerocapture, and later fly the correct aeroshell shape. It is recommended that aerocapture be flown early (demonstration of technique for inclusion in architecture), mid (include the human-class shapes and constraints), and late (included as part of more full-up demonstrations) VH= very high H = high M = medium L = low ES =Earth surface EO = Earth orbit MN = Moon MR = Mars E = Early M = Mid L = Late A = Anytime Code Requirement Rationale As s e s s m e n t TRL (aerocapture) 5 MREVH EXAMPLE COMPLETED TEMPLATE A

12 Very High Priority Items That Do Not Require Mars Testbed TechnologyWhereWhen Bio-Isolation SystemsMoonEarly/Mid Planetary ProtectionEarth SurfaceMid Connector DurabilityEarth SurfaceMid EXAMPLE OF VENUE CHOICE

13 MHP SSG Goal IVB – Technology Demonstration, Infrastructure Emplacement Priorities 1A. Conduct a Series of Three Aerocapture Flight Demonstrations [A]: –70 Deg. Sphere Cone Shape (robotic scale) to Demonstrate Aerocapture at Mars (Early). –New Entry Vehicle Configuration Suitable for Human Exploration (robotic scale), Aerocapture at Mars (Mid). –New Entry Vehicle Configuration Suitable for Human Exploration (Larger Scale, End-to-End Mission Sequence), Aerocapture at Mars (Late) –Rationale: Aerocapture is the Most “Effective” Means for Decelerating at Mars: 1. Chemical Propulsion - Massive Propellant 2. Direct Entry - Unacceptable “g”s for Humans; Landing Commitment From the Get-Go 3. Aerobraking – Lengthy (Unacceptable?) Time Commitment 4. Aerocapture – Mitigates Much of the Above Down-Side Demands Precision Entry and Attitude Control & Knowledge of Mars Atmosphere Characteristics - See IVA Measurements Goals Aerocapture May Be Mission Enabling

14 1B. Conduct a Series of Three In-Situ Resource Utilization Technology Demonstrations [S]: 1. ISRU Atmospheric Processing (Early) 2. ISRU Regolith-Water Processing (Early) 3. ISRU Human-Scale Application Dress Rehearsal (Late) –Rationale Reduce Mission Cost & Design Envelope Validate Earth-based Development & Testing Utilize Flight Demonstrations to Increase Confidence in ISRU Engage & Excite the Public –Sequence Progress from “Certain” Resource (Atmosphere) to Scattered (Hydrated Minerals, Regolith Ice) to Uncertain x, y, z Distribution (Subsurface Water) –See IVA Measurements Goals for Water-Related Items ISRU May Be Mission Enabling MHP SSG Goal IVB – Technology Demonstration, Infrastructure Emplacement Priorities

15 Risks & Impacts Associated with ISRU -Potential resource is not known with -Loss of opportunity to minimize mission enough confidence to include in mass, cost, and/or risk mission planning -Resource of minimum planned (required)Processing failure or reduced production accessibility, quality, and quantity is notrate: may lead to loss of mission if present at landing siteprocessing is critical > Accessibility is insufficient (e.g. depth, distance, produceability, mineability) > Resource quality is insufficient (e.g. concentration, mineralogy, impurities, state, T, etc.) > Resource quantity is insufficient - Processing system is vulnerable to - Processing failure or reduced production martian environmental effects (dust, rate: may lead to loss of mission if thermal gradient, conductivity, albedo, processing is critical, chemical effects, etc.) RiskImpact

16 1C. Demonstrate an End-to-End System for Soft, Pinpoint Mars Landing (10m to 100m accuracy) Using Systems Characteristics Representative of Mars Human Exploration Systems [A]. (Mid) –Rationale: Safety and risk mitigation: Landing near prepositioned supplies and emergency abort systems increases the likelihood of successfully accessing such in an emergency and enhances mission efficiency in non-emergency situations. Science accomplishment: a site selected for human exploration may be selected because there is a specific science objective to be accomplished. Such could be sufficiently localized that landing in close proximity increases the probability of successful science accomplishment. Mars Robotic Science Program May Independently Develop Pin-Point Landing Systems MHP SSG Goal IVB – Technology Demonstration, Infrastructure Emplacement Priorities

17 Goals 1A, 1B and 1C Testbed Sequencing Summary TechnologyRelated Precursors Early Testbed [2011 – 2016] Mid Testbed [2018 – 2022] Late Testbed [2024 – 2028] Aerocapture Goal 1A Atmospheric characterization (Early) Entry system instrumentation (All the time) 70-deg sphere cone demo (to possibly include subsequent EDL) New shape demo (to possibly include EDL) New shape end-to-end mission demo ISRU Goal 1B Find and characterize accessible water (Early) Atmospheric processing; regolith-water processing Human-scale dress rehearsal w/ascent Pinpoint Landing Goal 1C Landing site characterization (Anytime) Atmospheric characterization (Early) Entry system instrumentation (All the time) End-to-end system demo with human representative system characteristics

18 2A. Emplace Continuous, Redundant In-Situ Communications/Navigation Infrastructure. [S] (Late) Rationale: Mission Safety and Effectiveness will Require the Development of High Band-Width Continuous and Redundant Communications. Mars Telecom Orbiter is a Related Precursor MHP SSG Goal IVB – Technology Demonstration, Infrastructure Emplacement Priorities

19 2B. Investigate Long-Term Materials Degradation over times Comparable to Human Mission Needs. [S] (Mid) Rationale: Our Current State of Knowledge of the Mars Environment is Not Sufficient to Enable Confident Design of Essential Mars Surface Space Systems. These include EVA Suits, Habitats and Ancillary Systems, Including Mobility. It is Essential to Verify the Capability of Materials to Tolerate Long Term Exposure (years) to Mars Environmental Phenomena. These include: Radiation; Temperature Extremes and Cycles; Wind; Atmosphere Chemical and Electromagnetic Properties; Soil and Dust Chemical, Mechanical, and Electromagnetic Properties; and Mars biology (if any). MHP SSG Goal IVB – Technology Demonstration, Infrastructure Emplacement Priorities

20 3. Develop and Demonstrate Accurate, Robust and Autonomous Mars Approach Navigation. [T] (Mid) Rationale: This is a Mission Safety Item. It Would Provide a Backup/Replacement to DSN- based Terminal Navigation for a Mission Time- Critical Event Such As Mars Orbit Insertion or Aerocapture. MHP SSG Goal IVB – Technology Demonstration, Infrastructure Emplacement Priorities

21 General Observations Most Transit Sub-Team Items Do Not Need Demonstrations In Transit to Mars The Atmospheric Sub-Team Concentrated Primarily on Identifying System Level Technologies that Must be Demonstrated at Mars. Many Component-Level Items Exist Many Surface Sub-Team Items Were Transferred or Incorporated Into the Measurements (IVA) Short Stay versus Long Stay at Mars –Goals 1A, 1C, 2A and 3 are Independent of Stay Time –Goal 2B, Materials Degradation, Mosly Important for Long Stay –Goal 1B, ISRU, Mostly Applies to Long Stay Missions (Short Stay Could be a Useful “Assessment” Opportunity) Robotic Science Missions Can Contribute to Goal IVB –Pinpoint Landing Development –Mars Orbit Automated Rendezvous and Docking

22 TI Sub-Group Recommended Studies The TI Sub-Group Sees a Need for Systems-Level Studies – Optimal Configuration for Human Aeroassist Landing Vehicle – ISRU Trade Space

23 MEPAG 2001 MEPAG Demonstrate mid-range lift-to-drag (mid-L/D) aeroentry/aerocapture vehicle flight. Demonstrate high- Mach deployable aerodecelerator performance 1A Conduct a Series of Three Aerocapture Flight Demonstrations: Degree Sphere Cone Shape (Robotic Scale) to Demonstrate Aerocapture at Mars (Earlly) 2. New Entry Vehicle Configuration Suitable for Human Exploration (robotic scale), Aerocapture at Mars (Mid). 3. New Entry Vehicle Configuration Suitable for Human Exploration (Larger Scale, End-to-End Mission Sequence), Aerocapture at Mars (Late) 4545 Demonstrate In-Situ Propellant Production and In-Situ Consumables Production & Demonstrate In-Situ Water Collection and Conditioning Using Surface Resources. 1B Conduct a Series of Three In-Situ Resource Utilization Technology Demonstrations: 1. ISRU Atmospheric Processing (Early) 2. ISRU Regolith-Water Processing (Early) 3. ISRU Human-Scale Application Dress Rehearsal (Late) GOAL IVB Rewrite Summary - 1

24 MEPAG 2001MEPAG Demonstrate terminal phase hazard avoidance and precision landing 1C Demonstrate an End-to-End System for Soft, Pinpoint Mars Landing (10m to 100m accuracy) 6 Demonstrate access to subsurface resources (See IVA, Measurements, Report) 2A Emplace Continuous, Redundant In-Situ Communications/Navigation Infrastructure 7 Demonstrate plant growth in the Martian environment (Considered to be Low Priority by TI Sub- Group) 2B Investigate Long-Term Material Degradation Over Times Comparable to Human Mission Needs 3 Develop and Demonstrate Accurate, Robust and Autonomous Mars Approach Navigation GOAL IVB Rewrite Summary - 2