R2-S2: ROBOTIC REMOTE-SENSING SCOUT

Dan Brogan

dbrogan@usc.edu

M.S. Astronautical Engineering (Expected Dec. 2021)

ASTE 527: Space Concept Architectures

CONTEXT: THE U.S. LEADS COMMERCIAL HUMAN SPACEFLIGHT TO THE MOON

• NASA Artemis program establishes international partners for peaceful lunar exploration (2020) [1]

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• Commercial U.S. companies make major strides in crewed missions
• Virgin Galactic flight with Richard Branson (July 2021) [2]
• Blue Origin first crewed flight with Jeff Bezos (July 2021) [3]
• SpaceX Inspiration 4 first civilian orbital flight (Sept. 2021) [4]

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• NASA Artemis selects SpaceX for Human Landing System (2021) [5]

Signatures from Artemis Accords [1]

R2-S2: Robotic Remote-Sensing Scout

CONTEXT: ROBOTS FOR SUPPORTING CREWED MISSIONS

• Commercial Lunar Payload Services (CLPS) (Precursor to crewed lunar missions) [6]
• Surface measurements
• Demonstrating navigational technology
• Special Purpose Dexterous Manipulator (DEXTRE) (On-orbit) [7]
• Servicing and Repair
• Hardware replacement
• Carries tools during crewed EVA’s
• Canadarm (On-orbit) [8]
• Berthing
• Hardware assembly
• Astronaut positioning
• Multi-Mission Extra Vehicular Robot (MMEVR) (On-orbit) [9]
• Servicing and Repair
• Hardware assembly
• Can mount to Astronaut for augmented dexterity

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R2-S2: Robotic Remote-Sensing Scout

PROBLEM: THE NEED FOR A ROBOT TO ASSIST CREWED LUNAR OPERATIONS

Space Policy Document 1 (2018):

• “Lead an innovative and sustainable program of exploration with commercial and international partners…
• …the United States will lead the return of humans to the Moon for long-term exploration and utilization” [10]

Moon Village Association (2020):

• “Space actors are encouraged to share information to facilitate international cooperation among governmental agencies, private entities, and the general public in the expansion of lunar activities.” [11]

NEEDS:

• Dramatically reduce the risk associated with returning humans to the Moon
• Support the US in leading an innovative & sustainable program of exploration with commercial & international partners

GOALS:

• Provide the capability for remote sensing as well as in-situ mission assistance to commercially & internationally supported crewed Lunar EVA missions

OBJECTIVES:

• Ability to collect environmental data to help determine safety of planned EVA missions
• Ability to explore ahead of crewed missions to determine locations of scientific interest
• Ability to perform exterior inspection of habitats and launch vehicles
• Film EVA operations and livestream to Earth
• Perform specific tasks when commanded by the crew
• Carry emergency oxygen for the crew
• Provide high data-rate communications architecture
• Provide the above capabilities without endangering the crew
• Share all collected sensory data with commercial & international partners

RATIONALE: HOW R2-S2 FULFILLS THE NGO

What is R2-S2?:

• Lunar reconnaissance rover with two primary modes:
• Teleoperated by Lunar crew prior to EVA ops
• Autonomously assists alongside the crew during EVA ops

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High-Level Problems from NGO:

• Dramatically reduce the risk associated with returning humans to the Moon
• Support the US in leading an innovative & sustainable program of exploration with commercial & international partners

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How R2-S2 Addresses These Problems:

• R2-S2 Provides critical information for assessing the safety of Lunar EVA missions
• Alleviates crew workload during EVA missions and provides emergency capabilities
• R2-S2 will be a commercial & international effort led by NASA, and all data collected will be shared with commercial & international partners

R2-S2: Robotic Remote-Sensing Scout

ASSUMPTIONS

• There is already an established Lunar Habitat

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• R2-S2 is brought to the Moon via the Starship HLS

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• R2-S2 will not return to Earth

TELEOPERATED MODE: HIGH-LEVEL CONOPS

R2-S2: Robotic Remote-Sensing Scout

COMMUNICATION ARCHITECTURE

Moon Base <-> R2-S2:

• Radio (Nominal Control)

Moon Base <-> Earth:

• Laser (Nominal Monitor) [12]
• Radio (Contingency Monitor)

Earth <-> R2-S2:

• Radio (Contingency Control)

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OPERATIONS

1. EVA crew commander designated as Teleoperator (Teleop)
2. Teleop navigates R2 through terrain to perform desired task
3. R2 autonomously returns to habitat while EVA crew monitors its return and takes manual control if necessary

TELEOPERATED MODE: LUNAR CONTROL STATION

Display Interfaces:

• Virtual Reality (VR) headsets for entire EVA crew
• VR enhances mental preparedness of crew through sensory immersion
• External Monitor (Optional)

Control Interfaces:

• Game Controller
• Mouse and Keyboard (Optional)

R2-S2: Robotic Remote-Sensing Scout

TELEOPERATED APPLICATIONS

MISSION RECONNAISSANCE

1. A crewed EVA mission is planned
2. R2-S2 is teleoperated to gather data to determine safety of planned EVA mission

REMOTE EXPLORATION

1. Information is needed to plan the next crewed EVA mission
2. R2-S2 is teleoperated to gather information to help inform planning of crewed EVA mission

INSPECTION

1. Habitat exterior, surface vehicle, or launch vehicle needs inspection
2. R2-S2 is teleoperated to desired structure and performs visual inspection
• 3D imagery, IR, microscopy

R2-S2: Robotic Remote-Sensing Scout

AUTONOMOUS CREW-ASSIST MODE: HIGH-LEVEL CONOPS

R2-S2: Robotic Remote-Sensing Scout

COMMUNICATION ARCHITECTURE

EVA Crew <-> R2-S2:

• Radio (Control thru voice-command)

Moon Base <-> R2-S2:

• Radio (Nominal Monitor)

Moon Base <-> Earth:

• Laser (Nominal Monitor) [12]
• Radio (Contingency Monitor)

Earth <-> R2-S2:

• Radio (Contingency Control)

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OPERATIONS

1. R2-S2 follows EVA crew while monitoring crew and environment
2. R2-S2 performs specific tasks alongside crew when voice-commanded

AUTONOMOUS CREW-ASSIST MODE APPLICATIONS

R2-S2: Robotic Remote-Sensing Scout

1. Livestreams video of EVA operations to Earth

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• Performs specific tasks when commanded:
1. Sample collection
2. Telescoping
3. Microscopy
4. In-Situ measurements

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• Carries tools

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• Provides emergency supplies
• Oxygen
• Suit repair materials

R2-S2 OVERVIEW: POLAR & EQUATORIAL EDITION

R2-S2: Robotic Remote-Sensing Scout

Same incident solar area (same charging time)

Polar

Equatorial

• Wider wheels (Softer terrain) [13]
• Solar panels facing tangent to lunar surface
• Thicker battery back insulation

• Narrower wheels
• Solar panels facing normal to lunar surface
• Thinner battery back insulation

R2-S2 OVERVIEW: CAPABILITIES (PART 1/2)

R2-S2: Robotic Remote-Sensing Scout

1. Radio Antenna
• Nominal use: R2-S2<->Base
• Capable 10dB SNR to Earth if base comms are lost
2. Radiation Sensor [14]
• Detects protons, energetic ions, neutrons, & gamma rays
• Flown on Curiosity
3. 360˚ LiDAR [15]
• +10˚, -30˚ vertical FOV
• +/- 2cm accuracy
• 100m range
4. 360˚ HD Camera [16]
• 6x digital zoom
5. Stereo Telescoping Cameras [17]
• HD 3D imaging from afar
• Flown on Curiosity & Perseverance
6. Infrared Spectrometer [18]
• Temperature data
• Detection of volatiles
• Planned for VIPER
7. Microscope Camera [19]
• Minerology
• Flown on Curiosity

R2-S2 OVERVIEW: CAPABILITIES (PART 2/2)

R2-S2: Robotic Remote-Sensing Scout

8. Dual DC Motors [20]
• Total 0.25 hp
9. Subsurface Radar [21]
• 15-30cm vertical resolution
• 10m penetration depth
• Flown on Perseverance
10. Battery Pack
• 8-hour battery life assuming all systems are being used
• Aerogel insulation (2x thickness FOS)
• Polar: 3/8”
• Equatorial: 1/4”
11. Spare Oxygen Tanks
• Total 16 hours spare O2
12. Neutron Spectrometer [18]
• Detects volatiles & surface composition
• Planned for VIPER
13. Sample Collection Drill [18]
• 1m long
• Planned for VIPER
14. Wheels
• 40cm diameter aluminum rims
• Titanium spokes
• Rocker-Bogie configuration

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MERITS, LIMITATIONS, & FUTURE STUDIES

MERITS:

• Provides critical information to inform risk assessment of EVA missions
• Mentally prepares EVA crew through VR immersion
• Assists during crewed EVA excursions
• Shares data with commercial & international partners to further awareness of Lunar environment

LIMITATIONS:

• Terrain traversing abilities of a rover does not match that of a human in an EVA suit
• If R2-S2 becomes stuck, a crewed EVA mission will need to be planned to rescue it

FUTURE STUDIES:

• Robotic arm for more teleoperation capabilities
• Infrastructure for storing R2-S2 between missions
• Optimized drill placement

R2-S2: Robotic Remote-Sensing Scout

REFERENCES

[1] “Artemis Accords: Principles for Cooperation in the Civil Exploration and Use of the Moon, Mars, Comets, and Asteroids for Peaceful Purposes”. NASA. June 2021.

[2] Chang, Kenneth. “Highlights from Richard Branson's Virgin Galactic Flight.” The New York Times, 15 Sept. 2021, https://www.nytimes.com/live/2021/07/11/science/virgin-galactic-launch-richard-branson.

[3] Wall, Mike. “Jeff Bezos Launches into Space on Blue Origin's 1st Astronaut Flight.” Space.com, 20 July 2021, https://www.space.com/jeff-bezos-blue-origin-first-astronaut-launch.

[4] Stein, Vicky. “Inspiration4: The FIRST All-Civilian Spaceflight on SpaceX Dragon.” Space.com, 23 Sept. 2021, https://www.space.com/inspiration4-spacex.html.

[5] Lueders, Kathryn. “Appendix H: Human Landing System, Option A Next Space Technologies for Explorations Partnerships-2.” NASA. April 16, 2021.

[6] Potter, Sean. “NASA Awards Contract to Deliver Science, Tech to Moon.” NASA, 8 Apr. 2020, https://www.nasa.gov/press-release/nasa-awards-contract-to-deliver-science-tech-to-moon-ahead-of-human-missions.

[7] Coleshill, Elliott, et al. "Dextre: Improving maintenance operations on the international space station." Acta Astronautica 64.9-10 (2009): 869-874.

[8] Hiltz, Michael, et al. "Canadarm: 20 years of mission success through adaptation." (2001).

[9] Netti, Vittorio. "Design of an autonomous and teleoperated modular robotic free-flyer for EVA operations." ASCEND 2020. 2020. 4257.

[10] “Presidential Memorandum on Reinvigorating America’s Human Space Exploration Program”. The White House. Dec. 11, 2018.

[11] “Best Practices for Sustainable Lunar Activities.” Moon Village Association. October 19, 2020.

[12] Boroson, Don M., and Bryan S. Robinson. “The Lunar Laser Communication Demonstration: NASA’s First Step Toward Very High Data Rate Support of Science and Exploration Missions.” Space Science Reviews, vol. 185, no. 1, Springer Netherlands, 2014, pp. 115–28, doi:10.1007/s11214-014-0122-y.

[13] Moskowitz, Clara. “Shadows of the Moon Hide 'Fluffy' Dirt & Water Ice.” Space.com, 19 Jan. 2012, https://www.space.com/14284-moon-permanently-shadowed-regions-water-ice.html.

[14] "Radiation Assessment Detector (RAD)." NASA. 22 Apr. 2020. Web. 21 Sept. 2021.

[15] "Velodyne's HDL-32E SURROUND Lidar Sensor." Velodyne Lidar. 15 Sept. 2021. Web. 21 Sept. 2021.

[16] "Quantum 360 Rover Camera." Defender. Web. 21 Sept. 2021.

[17] “Mast-Mounted Camera System (MASTCAM-Z).” NASA, https://mars.nasa.gov/mars2020/spacecraft/instruments/mastcam-z/.

[18] Fong, Terry. "Volatiles Investigating Polar Exploration Rover (VIPER)." West Virginia University Robotics Seminar.

[19] “Mahli.” NASA, 22 Apr. 2020, https://mars.nasa.gov/msl/spacecraft/instruments/mahli/.

[20] "Right-Angle Shaft DC Gearmotor." McMaster-Carr. Web. 21 Sept. 2021.

[21] “Radar Imager for Mars' Subsurface Exploration (RIMFAX).” NASA. Retrieved September 21, 2021, from https://mars.nasa.gov/mars2020/spacecraft/instruments/rimfax/.

BACKUP SLIDES

R2-S2: Robotic Remote-Sensing Scout

R2-S2 TERRAIN HAZARD DETECTION SYSTEM

R2-S2: Robotic Remote-Sensing Scout

ANTENNA SIZING & POWER BUDGET

R2-S2: Robotic Remote-Sensing Scout

RADIO VS. LASER COMMUNICATION

R2-S2: Robotic Remote-Sensing Scout

Green = Pros

Red = Cons

RATIONALE FOR COMMS ARCHITECTURE SELECTION

R2-S2: Robotic Remote-Sensing Scout

R2-S2 Rover

• Nominal comms: Radio
• Less strict pointing requirements
• R2-S2 will be moving around a lot
• Less sensitive to physical obstruction
• R2-S2 may need to explore caves and tunnels

Moon Base

• Nominal comms: Laser
• Stricter pointing requirements
• Easy to point at Earth from stationary base
• Higher data rate
• Better for HD livestreaming
• Contingency comms: Radio

Earth

• Nominal comms: Laser
• Stricter pointing requirements
• Easy to point at the Moon from stationary facility
• Higher data rate
• Better for HD livestreaming
• Contingency comms: Radio

BATTERY PACK DESIGN: APPROXIMATE HEAT TRANSFER MODELS

R2-S2: Robotic Remote-Sensing Scout

EQUATORIAL NIGHTTIME & POLAR OPERATIONS:

EQUATORIAL DAYTIME OPERATIONS:

BATTERY PACK DESIGN: INSULATION SIZING (EQUATORIAL DAYTIME)

R2-S2: Robotic Remote-Sensing Scout

R2-S2: Robotic Remote-Sensing Scout

BATTERY PACK DESIGN: INSULATION SIZING (EQUATORIAL NIGHTTIME)

BATTERY PACK DESIGN: EQUATORIAL CHARGE TIME

R2-S2: Robotic Remote-Sensing Scout

BATTERY PACK DESIGN: INSULATION SIZING (POLAR)

R2-S2: Robotic Remote-Sensing Scout

BATTERY PACK DESIGN: POLAR CHARGE TIME

R2-S2: Robotic Remote-Sensing Scout