ENAE483 Project 1. David Nestor Skylar Trythall Matt Vaughn Ryan Quinn

Transcription

1 ENAE483 Project 1 David Nestor Skylar Trythall Matt Vaughn Ryan Quinn

2 9. Con-ops Outline 1. Transport Design 2. Transport Interior Design 3. Life Support and Logistics for Transport Design 4. Habit Design 5. Habitat Interior Design 6. Life Support and Logistics for Martian Habitat 7. Contingency Planning 8. Mission Architecture

3 I. Transport Design

4 Mission Constraints Mass Empty Gross Mass <22 MT (NASA RASC-AL 2018) [1] Total Gross Mass <43 MT [1] Crew Members 4-6 (ENAE 483 Project Outline) Artificial Gravity Martian Gravity (3.73 m/s^2) Earth Gravity (9.81 m/s^2)

5 Artificial Gravity Transport Design Process Initial design concept: Create Artificial Gravity (AG) through centripetal acceleration (CF) Need to consider human compatibility with angular velocity [4, Globus] 1-2 RPM avoids motion sickness (G) 3-4 RPM requires training by visitors (G) 5-6 RPM requires adjustment time and training by visitors (G) 7-10 RPM requires immense training but may not be suitable for aerospace structures (G)

6 Artificial Gravity Transport Design Process Initial design was for a full torus with a habitable height of 2.5 m Minimum height requirement from 95 percentile male 2.5 m [2] No adjustment for habitable volume being less than pressure volume for gross mass calculations

7 Artificial Gravity Transport Design Process At Earth gravity a maximal RPM of 7 requires an approximate outer radius of 18 meters Full torus design at 18 meter radius requires approximately 160 MT Doesn t meet design constraint of 22 MT At Martian gravity a maximal RPM of 7 requires an approximate outer radius of 7 meters Full torus design at 7 meter radius requires approximately 90 MT Doesn t meet design constraint of 22 MT Conclusion is that a full torus will not be able to meet gross mass restrictions at either Martian or Earth gravity Consider breaking torus into different modules

8 Artificial Gravity Transport Design Process Reconsidered design for mass calculations to be based off of total pressurized volume [3]. As recommended Dr. David L Akin at the University of Maryland, a scaling increase of 0.75 was used Habitable_volume = 0.75*Pressurized_volume Knowing that recommended habitable volume is 25 m^3 per person Scaled habitable volume as previously stated to generate plot shown

9 Reevaluation of Design Constraints It is necessary to break up full torus to meet mass requirement Decided on 3 habitable modules for rotational stability Angular Velocity should be between 6 and 7 RPM Minimizes outer radius and thus gross mass while achieving Earth gravity Concluded a maximum of 4 crew members to meet mass requirement Minimum habitable volume of 100 m^3 3 modules at ~33.3 m^3 each Need to design modules off of human comfort and volume/mass constraints Height

10 Passages connecting habitable modules to central docking/airlock hub Internal Dimension Considerations (1 of 2) Comfortability assumptions for habitable modules: Walking width (initial assumption) 3 m Length Designed to meet minimal habitable volume Curved to keep gravitational levels constant from end to end Hemispherical end caps to hold internal pressure Radius = 1.25 (to accommodate previously stated height requirement)

11 EVA hatch Internal Dimension Considerations (2 of 2) Central docking/airlock hub: Diameter of NASA Docking System (NDS) [6] Diameter = 0.81m Size requirement for storage of 2 EVA suits [5] EVA Suit: Width = 0.9m, Depth = 0.7m, Height = 1.9 m Internal docking hub radius of 1.25 m will: Hold 2 EVA suits radially against the wall Support 2 NDS at either end of the hub

12 Gross Mass From Design Dimensions Angular Velocity 6 RPM at Earth Gravity Outer Radius m Pressurized volume m 3 Habitable volume 234 m 3 Gross mass 43.4 MT Angular Velocity 6 RPM at Mars Gravity Outer Radius 6.94 m Pressurized Volume m 3 Habitable Volume 234 m 3 Gross mass 40.7 MT NOTE: Passageways and docking/airlock hub do not count toward habitable volume

13 Gross Mass From Design Dimensions Angular Velocity 7 RPM at Earth Gravity Outer radius 18.3 m Pressurized volume m 3 Habitable volume 234 m 3 Gross mass 42.3 MT Angular Velocity 7 RPM at Mars Gravity Outer radius 7 m Pressurized volume m 3 Habitable volume 234 m 3 Gross mass 40.3 MT NOTE: Passageways and docking/airlock hub do not count toward habitable volume

14 Design Considerations From Mass Estimations Passageways and airlock/docking hub minimized by previous requirements Necessary to reduce habitable module volume to reduce gross mass further Considering hemispherical endcaps as habitable volume Allows for reduction of walking width to NASA minimum requirement (.81 m) Allows for reduction of total length of module To match minimum habitable volume 100 m 3 for 4 crew members Radius 1.25 hemispherical endcaps

15 Minimized Gross Mass Angular Velocity 7 RPM at Earth Gravity Outer Radius 18.3 m Pressurized Volume m 3 Habitable Volume 100 M 3 Gross Mass 26.1 MT Angular Velocity 7 RPM at Mars Gravity Outer Radius 6.9 m Pressurized Volume m 3 Habitable Volume 100 m 3 Gross Mass 23.8 MT NOTE: Passageways and docking/airlock hub do not count toward habitable volume Minimal mass only achievable at Martian Gravity

16 Final Internal Dimensions Central Airlock/Docking Hub: Radius 1.25 m Length 2.31 m EVA hatch diameter 1 m NDS (x2) radius 0.81 m Passageways: Diameter 0.81 m Length 3.2 m Habitable Modules: Walking Width 0.81 m Arclength 3 m Height 2.5 m Endcap radii 1.25 m NOTE: For minimized gross mass at Martian gravity

17 Stability Destabilizing forces to consider: Mass imbalance from all four passengers residing in a single module Solar pressure exerting a torque about one of the principal axes Control techniques to do further investigation on: Utilizing fuel crossfeed as a control strategy to keep the spacecraft stable about the rotational axis Possible loss of control authority as fuel is used Analysis of whether or not system is uniformly controllable using only retrograde-facing thrusters in an emergency situation Will require a linearization of Euler s rotational equations of motion

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19 II. Transport Interior Design

20 Internal structure Each pod serves one function Living Recreation/Health Research Four beds, each with a collapsible screen to provide passengers privacy 2 Ergometers for exercise Lab equipment and experiments Bathroom Kitchen area Overhead bin storage for lab supplies Shower Laundry

21 Living area Four beds located in the hemisphere endcaps Spacing in between beds consistent with NASA-STD-3000 Bathroom and shower (opposite) on the center edges of the module Ladder to passageway in very center of module Each bed features a pull-down boron-lined shield for both privacy and radiation protection, two drawers underneath for personal and mission related storage, and a window.

22 Floor Plan for Personal and Sleeping Module

23 Living Area Bed and side cut of boron-lined privacy shielding Bedding setup Crew member view out of the window on arrival at Mars

24 Recreation Area Two ergometers for exercise Food preparation area Laundry area Television to increase comfort of trip for crew

25 Floor Plan for Kitchen, Exercise, and Rec Module

26 Research area Each wall consists of a long laboratory table Lab safety equipment at far end of module Fire extinguisher Fire-proof bags Eye-washing station 3D Printer included to assist in all experiments as needed

27 Floor Plan for Research Area

28 III. Life Support and Logistics for Transport Design

29 Transport Pressurized Volume Requirements Support kpa at 21% O 2, 1% CO 2, & 78% N 2 [1] Temperature maintained at 25.5 C (ISS max average) [7] Partial Pressure O kpa Mass O kg Partial Pressure CO 2 1 kpa Mass C0 2

30 Pressurized Volume Requirements Support maximum 0 2 partial pressure of 26% during depressurization for EVA s [1] Temperature maintained at 25.5 C [9] Partial Pressure O kpa Mass O2 61 kg Requires an extra 11.7 kg of O 2 during preparations for EVA s

31 Water and Air Recycling System Pressurization of atmospheric gases to be maintained by closed loop air control system Oxygen levels to be maintained through use of electrolysis of water (H 2 O) 2H 2 O + electricity 2H 2 + O 2 Hydrogen (2H) is also produced through electrolysis as a byproduct Hydrogen produced by electrolysis to be combined with scrubbed carbon dioxide (CO 2 ) through a Sabatier Reaction [8] 4H + CO 2 2H 2 O + CH 4 Water produced through reaction to be recycled through Water Revitalization System (WRS)

32 Water and Air Recycling System CO 2 scrubbing through use of adapted ISS 4 bed molecular sieve [1] Molecular sieve utilizes airflow of zeolite that condenses water vapor and CO 2 onto its surface This removed CO 2 is then used in the Sabatier Reaction to reproduce water and methane Water recollected through zeolite is sent back into the WRS Requires 30 day backup of lithium hydroxide canisters Current ISS WRS can reclaim 93% of water within the closed loop system [7] This includes the recycling of urine that some astronauts of other cultures refuse to consume This transport will require the use of the full capability of the WRS and thus includes reclamation of water within urine

33 1023 gallons Water and Air Recycling System Reclaiming 93% of 12 gallons a day Required 30 day backup supply of no reclamation 360 gallons Maximum 400 day transport to Mars [1] requires: 348 gallons Maximum 360 day transport back from Mars [1] requires: 315 gallons Total necessary water for complete transit

34 Total necessary food for complete transit Food Requirements Current mass of ISS foods at.83 kg per meal per person[9] Assuming 3 meals a day for 4 crew members Required 30 days of backup food supply.3 MT Maximum 400 day transport to Mars [1] requires: 3.98 MT Maximum 360 day transport back from Mars [1]requires: 3.59 MT

35 Locate return valve on opposite end of habitable modules to even out molecules within the module and return air through ECLSS system and back to center hub Air Circulation Air revitalization & maintenance system to be through closed loop process Revitalized air will be dumped into central docking port after going through CO 2 scrubbing, O 2 electrolysis production, etc. As air enters docking port chamber artificial gravity will pull molecules towards habitable modules Tangential velocity from rotation will push air molecules to one end of the habitable modules

36 Maintain around Thermal Control Accommodates astronaut comfortability found in ISS Use modified External HFE 7200 and external radiators mounted around passageways to regulate temperatures Radiators may also serve as Micrometeorites and Orbital Debris MMOD protection on passageway hull [1]

37 Power Requirements Consider power ratings of past long term manned space craft Max Power Consumed (Kw) Hab Volume (m 3 ) Prs Volume (m 3 ) Crew Size Station Mass (MT) Salyut 1& Salyut 6& MIR Skylab ISS 90 (160 capable) Tiangong 1& (T1) 2(T2) 8.5

38 Power Requirements Total station mass also includes logistic and consumable mass Compare pressure volume with max power consumption Comparison yields a first draft approximation equation for the amount of power to run just the habitat Where Y is power consumption (kw) Where X is pressurized volume (m 3 ) Y = 7e -7 (X 2 ) *X Max power consumption for Transport 7.42 kw

39 Solar Array ISS currently has 16 solar arrays to produce a total power of 160 (kw) 160 kw not all used for the habitat Each solar array is 112 ft x 39 ft [10] ISS 1 ISS arrays produces and power around system 10 kw are able to produce 2.29 W per ft 2 Production of solar arrays already determined Transport requires a minimum of 3,242 ft 2 of solar arrays to support habitat Use 1 ISS solar array minimum to maintain habitat livability Others to be determined by power and propulsion constraints [10]

40 Deep space capabilities Communications Requirements Using X-band and/or Ka-band for radio frequency Television equipment Optical/laser device Deep space atomic clock Guidance and Navigation equipment Space security system

41 IV. Habitat Design

42 Habitat Design Habitat orientation was picked to utilize transport module geometries and some dimensions Endcap radii were kept at 1.25 m Module width was adjusted to give 2.5 m head room Module length was adjusted to 7.1 m to provide the minimum 100 m^3 habitable volume for 4 people Pressure volume adjusted mass calculations showed that these internal dimensions yielded a gross mass of 18.6 MT A higher volume ratio was used due to the Martian atmosphere and possible use of regolith as

43 Habitat Airlock Design The airlock was based off the central docking hub EVA hatch is oriented to be at ground level Only one NDS will be needed to attach the airlock to the habitat Cylindrical length = 1 m Radius = 1 m Endcap radii = 1 m These dimensions will allow all 4 crew to fit in the airlock while wearing their pressure suits in case of an emergency

44 V. Habitat Interior Design

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49 VI. Life Support and Logistics for Martian Habitat

50 Habitat Pressurized Volume Requirements Support kpa at 21% O 2, 1% CO 2, & 78% N 2 (NASA RASC-AL 2018) Temperature maintained at 25.5 C (ISS max average [8]) Partial Pressure O kpa Mass O kg Partial Pressure CO 2 1 kpa Mass C0 2

51 Habitat Pressurized Volume Requirements Support maximum 0 2 partial pressure of 26% during depressurization for EVA s [1] Temperature maintained at 25.5 C [9] Partial Pressure O kpa Mass O2 40 kg Requires an extra 7.65 kg of O 2 during preparations for EVA s

52 Water and Air Recycling System Using the same WRS & O 2 recovery from electrolysis Reclaiming 93% of 12 gallons a day Required 30 day backup supply of no reclamation 360 gallons Maximum 550 days on Martian orbit and surface stay (NASA RASC-AL 2018) requires: 462 gallons Total necessary water for Martian orbit and surface stay 822 gallons

53 Food Requirements Current mass of ISS foods at.83 kg (including packaging) per meal per person [10]. Assuming 3 meals a day for 4 crew members Required 30 days of backup food supply.3 MT Maximum 550 days Martian orbit and surface stay [1] requires: 5.48 MT Total necessary food for complete transit 5.78 MT

54 Air Circulation, Thermal Control, Communications, and Solar Array Air revitalization & maintenance system to be through closed loop process Revitalized air will be dumped into central docking port after going through CO 2 scrubbing, O 2 electrolysis production, etc. Any produced CO 2 and CH 4 to be dumped into Martian atmosphere Air entry valve at top center of the habitat Return valves at both bottom ends of the habitat Use modified HFE 7200 thermal control system to maintain 25.5 Communication device to relay to signals from Martian surface - to transport

55 VII. Contingency Plans

56 NOTE: Any emergency situation will initiate a propulsion system shutdown and Emergency Design Considerations Fire: Electrical panels will have holes for extinguisher nozzles 2 Fire extinguishers per pod and 1 just outside docking hub Depressurization: There will be vacuum sealing doors between all passageways and the docking hub The section that has the pressure leak will be sealed off until the issue has been resolved

57 VIII. Mission Architecture

58 Selection of launch date Select launch to minimize ΔV Solve for orbits iteratively using a Lambert s problem solver Launch dates beginning near the start of 2029 to correlate with RASC-AL technology readiness requirements Choosing result with lowest V & C3 values results in a tentative launch window of Departure: January, 2029

59 Launch Timeline (1 of 2) First Launch (Month 0) Third Launch (Month 21) Launch with SLS 1B Launch with Falcon Heavy Direct to Trans-Mars Injection (TMI) Direct to L5 Habitat to Mars Construction Crew No logistics 1 year logistics & ECLSS Unloading crane Fourth Launch (Month 24) Second Launch (Month 12) Launch with SLS 1B Launch with SLS 1B Direct to L5

60 Launch Timeline (2 of 2) Construction Complete (Month 36) Full assembly Return of construction crew Fifth Launch (1-2 Months ahead of sixth launch) Sixth Launch (Month ~ 36 or later) Launch with SLS 1B Direct to L5 Transport Crew Launch with Falcon Heavy 760 days of: Direct to TMI Logistics Mars habitat logistics and consumables Consumables

61 First Launch Mass Estimations Landing Habitat and Airlock Second Launch Mass Estimations Habitable module 18.6 MT 6.61 MT Remaining Mass of SLS 1B Docking/Airlock hub 14.4 MT 7.76 MT To be used for unloading crane Passageway MT Total

62 Third Launch Mass Estimations Fourth Launch Mass Estimations Habitable Module (x2) Construction crew & flight craft MT Dependant on flight vehicle and crew Passageway (x2) 1 year consumables MT Including 3 month safety supply 3 Month Consumable Resupply Water Water 2.56 MT MT Food Food 3.59 MT

63 Fifth Launch Mass Estimations Mars Mission Consumables Sixth Launch Mass Estimations 4 Crew Members With 3 month back-up Water 3.16 MT Food 6.3 MT Total 9.6 MT Flight Vehicle Consumables for Entire Transit With 3 month back-up supply Water 3.9 MT Food 7.6 MT

64 Mars Mission Crew Arrival Procedure Descend from transport in Orion lander to habitat landing site Use orion lander as a temporary habitat while using the crane to unload habitat and airlock Assemble habitat and airlock on Mars surface After assembly is complete, move supplies and logistics into habitat for surface mission

65 IX. Con-Ops

66 Day-to-day Operations On transit to Mars, and on Mars, crew will plan their days according to Martian day (Sol) Timeline of 1 Sol in Martian hours (1.027 Earth Hours): hrs. (8.216 Earth hrs.) Sleep hrs. (1.027 Earth hrs.) Wake-up / Breakfast / Rectime hrs. (4.108 Earth hrs.) Work hrs. (1.027 Earth hrs.)

67 Day-to-day Operations On return transit to Earth crew will plan their days according to Earth days Timeline of 1 Earth day: hrs. Sleep hrs. Wake-up / Breakfast / Rectime hrs. Work hrs. Lunch

68 X. Experimental Testing Plans

69 Full Scale Flat geometry pod Curved geometry means that during Earth-based testing, the gravity vector will be pointing in the wrong direction To confirm that layout is as ergonomic as possible to crew members while testing on Earth, a flat geometry model will be created. This allows crew members to experience life on the spacecraft with respect to gravity as closely as possible to on-orbit conditions. On-orbit configuration Surface test configuration

70 Air circulation under rotation Possibility of spacecraft acting as a centrifuge, pushing air towards the edge of the spacecraft Nitrogen level of the spacecraft could be effected as the more massive particles are dragged out towards the edge Possible dead spots in areas Use CFD modeling to determine the extent of these effects

71 Gravity Gradient During Intermodule Transit Crew will experience varying levels of gravity while transferring from one module to another A study should be done into the difficulties this variance poses to a human climbing the ladder Experiment by using a neutral buoyancy tank with an experimenter climbing a ladder as a secondary diver removes weights from the experimenter in progression

72 Effect of Gravity Gradient on Human Body Effective gravity differences from head to foot could be significant to passengers Due to the small radius of curvature This difference for a 1.85m tall crew member corresponds to m/s 2 Testing for this difference will be done by having a diver in the neutral buoyancy pool wear varying weights from head to foot while accomplishing routine tasks

73 Structural Analysis of Solar Array Design Ensure that the solar arrays in current configuration can withstand the axial stresses Stress caused by rotation of the spacecraft Testing method Scaled down attaching arm and array will be attached to a motor spinning at 7rpm Measure stresses and strains in array and attaching arm from rotation Convert to full scale concept Determine a dominant design

74 XI. Appendices

75 Appendix A.

76 References [1] Rascal.nianet.org. (2017). Themes RASCAL. [online] Available at: [Accessed 23 Oct. 2017]. [2] NASA-STD (1995). Man-Systems Integration standards. Houston: NASA Johnson Space Center. [3] Akin, D. (2017). Mass Estimating Relations. [4] Globus, Al. (2015). Space Settlement Population Rotation Tolerance. University of Michigan. [5] Cullingford, H.S. Development of the CELSS Emulator at NASA JSC, SAE Technical Paper Series. Jan

77 References [6] Internal Docking System Standard (IDSS) Interface Definition Document (IDD) [7] On-Orbit ISS ECLS Hardware Distribution as of February (2010) NASA. [8] Junaedi, C., Hawley, K. and Walsh, D. (2017). Compact and Lightweight Sabatier Reactor for Carbon Dioxide Reduction [online] Ntrs.nasa.gov. Available at: [Accessed 29 Oct. 2017]. [9] Nasa.gov. (2017). NASA - Human Needs: Sustaining Life During Exploration. [online] Available at: [Accessed 29 Oct. 2017].

78 References [10] NASA. (2017). International Space Station: Solar Arrays. [online] Available at: [Accessed 31 Oct. 2017].