Sprint 1: Return to the Moon without ISRU
Deliverable Guidelines
The deliverable of Sprint 1 is a lunar-only architecture based on Ed Crawley's 2/11/19 lecture on architecture: Lecture: Prior Lunar Studies, Apollo Decisions in Architecture. We are encouraged to use SpaceNet to model our design.
We are required to ensure our solutions suit both govt and commercial customers. The first customer, Jeff, the NASA representative, is open to what a lunar architecture would look like if we are just simply going to the Moon without thinking about Mars and without the use of ISRU. He added that in future Sprints, we will expand the mission complexity and purposes.
As the representative of the “private company” stakeholder, Javier is interested in opportunities in our architecture for a private company to provide a service in a competitive manner. For this to happen, and for it to be beneficial to the government that is driving the exploration program, it would have to be a service that could realistically be competed amongst several private companies. One good example of this is the ISS cargo and crew contracts. When the Shuttle was retired, private companies took over delivering cargo and (soon) crew to the ISS. Two companies were selected and awarded fixed price contracts for the service.
Javier continues to state that for our lunar architecture, several possible similar capabilities come to mind: for example, most of the mass we launch is going to be fuel. Thus, would it make sense for NASA to buy fuel “by the gallon, on orbit”? That is, private companies launch fuel to a set orbit, and NASA uses it for its missions. Another possibility is autonomous roaming rovers on the moon surface. Private companies develop them, and NASA pays “by the mile” of surface covered, or something like that.
Note that historically, private companies have made money in space primarily by selling services to the government, usually on a “cost-plus” basis: the companies get paid what it costs, plus a small fee. That is not what Javier is looking for here. He is looking for "money-making opportunities that also reduce the cost to the government, which ultimately evolve into self sustaining economic activities".
Morphological Matrix
| Decision | Option 1 | Option 2 | Option 3 | Option 4 | Option 5 |
|---|---|---|---|---|---|
| Earth Launch | LEO | L1 | L2 | Lunar Orbit | Lunar Surface |
| Earth Orbit Rendezvous | None | LEO Station | Orbital Maneuvering | ||
| Lunar Orbit Rendezvous | None | Gateway Docking | LLO | ||
| Lagrange Point Rendezvous | L1 Rendezvous | L1 Docking | L2 Rendezvous | L2 Docking | None |
| Moon Surface Arrival | Direct from Earth | Direct from LEO | Arrival from L1/L2 | Arrival from LLO | Arrival from Gateway |
| Lunar Surface Location | Near-side Equator | Far-side Equator | South Pole | ||
| Moon Surface Ops | Human EVA only | Sample Return | Unmanned Rover | Manned Rover | |
| Moon Departature | Gateway | LLO | L1/L2 | LEO | Earth |
| Crew Selection | 1 | 2 | 3 | 4 | 5 |
| Fuel Type | Solid | Liquid | Hybrid | Hypergolics |
Proposed Designs
Apollo 17 Baseline
- Crew size: 3
- Single launch
- Delta V requirements: 21 km/s
- KSC->LLO->LEQ->LLO->PAC
- 2 crew to surface, 1 remains in LLO
- Payload: rover, science instrumentation
Constellation/Orion
- Crew size: 4
- Cargo launch and crew launch
- Delta V requirements: 21 km/s
- KSC->LEO->LLO->LSP->PAC
- 4 crew to surface
- Payload: rover, science instrumentation, sample return
Commercial Mission
- Crew size: 4
- Cargo launch and crew launch
- Delta V requirements: 23.1 km/s
- KSC->NRHO->LSP->NRHO->PAC
- 4 crew to surface
- Payload: base, rover, science instrumentation, sample return
MARS (Moon Again Reliably to Stay)
- Crew size: 4
- Cargo launch and crew launch
- Delta V requirements: 23.1 km/s
- KSC->LEO->LLO->ANY>PAC
- 4 crew to surface
- Payload: base, rover, science instrumentation, sample return
NASA Design Reference Mission (2028)
- Crew size: 4
- Crew, lunar ascent element refuel, lunar descent element, and transfer vehicle element refuel
- Delta V requirements: 23.1 km/s
- KSC->NRHO->LSP/LEQ->NRHO->PAC
- 4 crew to surface
- Payload: rover, science instrumentation, sample return
Architecture Trade Study
Architecture Decision Points
- Lunar Orbit Rendezvous
- Earth Orbit Rendezvous
- Landing Site Selection Trade
- Lunar Gateway
- SpaceNet Demo
- Launch Vehicle Feasibility Trade
- Crew Trade Study
- Risk Analysis
- Reusability/Lifecycle Costs
Launch Vehicle Trade Study Selection: New Glenn 3-Stage for Cargo; New Glenn 2-Stage for Crew
Rationale: New Glenn 2-Stage intends to complete its first test by 2020. If a 2-year schedule slip occurs, the New Glenn 2-Stage will still have been tested multiple times and is thus safer to transport crew. The New Glenn 3-Stage, while heavier, will not have the same amount of completed tests and is best for cargo transportation. The performance vs cost of SLS is not well-suited for the lunar environment. Data on Russian and Chinese options are not comprehensive. Falcon Heavy proves to be a smaller rocket than the SLS and New Glenn.
Constraints
- 21 day duration (radiation-limited)
- Initial launch date
- Launch from Kennedy Space Center
Evaluation Metrics
- Mass to lunar surface
- Development risk
- Reusability
- Crew safety
- Profit incentive
Proposed Architectures
| Alternatives | ||||||
|---|---|---|---|---|---|---|
| Moon - Earth Architecture
Decisions (Non-ISRU) |
Apollo | Commercial | Constellation | MARS | NASA Design Reference Mission | |
| Earth Launch | Earth Launch | Direct to Earth Orbit | Direct to Moon Orbit | Direct to Earth Orbit | Direct to Earth Orbit | Direct to Moon Orbit |
| Earth Orbit Rendezvous | Earth Orbit Rendezvous | Earth Orbit Positioning | Earth Orbit Positioning | Earth Orbit Positioning | ||
| Lunar Orbit Rendezvous | Lunar Orbit Rendezvous | Orbit Without Docking | Gateway Docking | Orbit Without Docking | Orbit Without Docking | Gateway Docking |
| Moon Surface Arrival | Landing Process | Arrival from Moon Orbit | Arrival from Gateway | Arrival from Moon Orbit | Arrival from Moon Orbit | Arrival from Gateway |
| Landing Site Selection (General | Taurus-Littrow Valley | South Pole (Shakleton Crater Area) | Lunar South Pole | Anywhere | Anywhere | |
| Moon Surface Operations | Total Duration on Moon Surface | 75 hours | 14 days | 7 days | 7 days | 7 day lunar sorties; exact number flexible |
| Total Anticipated EVA time | 22 hours | 1. 8 hours EVA
2. 138 hours On-Duty (drive time, daily briefs, IVA maintenance,meals, contextual observations) |
1. 14 hours EVA
2. 72 hours performing operations in lunar rover |
1. 10 hours EVA
2. 48 hours in lunar rover |
Varies | |
| Anticipated Return Sample Mass | 110kg | 500kg | 500kg | 500kg | Varies | |
| Moon Departure | Direct to Moon Orbit | Direct to Moon Orbit | Direct to Gateway | Direct to Moon Orbit | Direct to Moon Orbit | Direct to Gateway |
| Crew Composition | Command Module Crew Size | 3 | 4 | 4 | 4 | 2-4 |
| Lunar Module Crew Size | 2 | 4 | 4 | 4 | 2-4 | |
| Fuel Type | Service Module Fuel | Aerozine 50 fuel
nitrogen tetroxide oxidizer |
Hypergolic Propellants or Liquid Oxygen / Methane | Liquid Oxygen / Methane | Liquid Oxygen / Methane | TBD |
| Lunar Module Fuel | Aerozine 50 fuel
nitrogen tetroxide oxidizer |
1. Descent Stage: Liquid Oxygen / Liquid Hydrogen (LOX/LH2)
2. Ascent Stage: Hypergolic Propellants or Liquid Oxygen/Methane |
1. Descent Stage: Liquid Oxygen / Liquid Hydrogen (LOX/LH2)
2. Ascent Stage: Hypergolic Propellants or Liquid Oxygen/Methane |
1. Descent Stage: Liquid Oxygen / Liquid Hydrogen (LOX/LH2)
2. Ascent Stage: Hypergolic Propellants or Liquid Oxygen/Methane |
TBD | |
Final Architecture
Our analysis showed a variation on the Constellation Mission as the best architecture for a successful return to the moon
- Crew size: 4
- Cargo launch and crew launch
- Delta V requirements: 21 km/s
- KSC->LEO->LLO->LSP->PAC
- 4 crew to Lunar South Pole
- Surface Duration: 7 days
- EVA Duration: 40 hours
- Payload: rover, science instrumentation, sample return
Delta-V Chart
SpaceNet Demo
Constellation SpaceNet Simulation: https://youtu.be/xXaaAa5c3zU
Gateway SpaceNet Simulation: https://youtu.be/i4SDN5_Mcv8
Sprint 1 Feedback
Space Systems Engineers (16.89/IDS.339 Students):
After your demo 1 yesterday I wanted to provide you with some written feedback which should help you for sprint 2 and beyond
- 1. The demo should be fully setup and ready to go at 10:35AM, including video and audio working and tested ahead of time
- 2. No need to make special PPT charts. The demo is NOT a presentation but a live discussion and demonstration of the work product such as report, working software, etc... the demo is directly on the work product, not a summary of it via PPT. This is one of the principles of agile.
- 3. You showed a quite comprehensive Morphological Matrix with the major decisions to make for a lunar return architecture with human crew. You should not only show the morphological matrix but also enumerate all the combinations of decisions that are apriori feasible, i.e. don't violate any logical constraints. How many such architectures can you generate
- 4. Be clearer about which Figures of Merit (FOM) you will use to evaluate these architectures and compare them against each other. Examples: total cargo mass delivered to lunar surface divided by launch mass, Exploration Capability (crew surface days times cargo mass to surface) etc... especially metrics that can be used to evaluate the business case of a commercial company (e.g. $/crew hour on lunar surface) would be interesting.
- 5. Apollo 17 is one of your reference architectures. Good evaluate the other architectures and normalize by Apollo 17 numbers.
- 6. You showed 5 "preferred" architectures and then even went as far as presenting a "final" architecture that you recommend. That is going too far, too fast. Take your time to gradually refine your architecture evaluation and selection. I would like to see a "cloud of points", each point showing a different architecture evaluated using different FOMs such as (lifecycle cost LCC, cargo mass to surface, risk (e.g. counting the number of safety-critical mission events).. then filter for the non-dominated architectures and show that smaller set. Show where in this point cloud your 5 architecture fall.
- 7. The idea is that in Sprint 1 you create the tradespace and all possible combinations (without ISRU). In sprint 2 and 3 you expand to include lunar ISRU and evaluate all architectures), then you can overlay the sprint 1 and sprint 2 point clouds to find architectures without initial ISRU that may initially look dominated, but with ISRU in the picture they become non-dominated, i.e. more interesting. Then after Spring break, sprints 4,5 and 6 this can be repeated but now by comparing Moon, versus Mars architectures to find those Moon architectures that may be the most interesting as a "stepping stone" to Mars
- 8. Lunar Landing Locations. NASA has a clear ambition to land now everywhere on the lunar surface, including the poles, especially the South Poles and potentially even the far side, as long that continuous communication with Earth is guaranteed. This means the SpaceNet network of lunar landing sites needs to be expanded into actual nodes, with calculation of delta-vs to those different lunar surface locations from LLO, NRHO and potentially EML1. This is essentially a lunar surface analysis both directly from Earth, and indirectly via the Gateway.
- 9. When you look at the mass delivered to the lunar surface, make sure you think about what kind of mass is delivered (classes of supply 1-10) including crew, consumables, mobility equipment etc.. its probably okay to delay this more detailed mass breakdown until sprint 3.
- 10. Contingency analysis. At some point start considering failure modes and contingencies and which architectures are more robust to specific element failures (e.g. ascent stage) or event failures (e.g. rendezvous).
- 11. Compared to typical 16.89 classes that were run in waterfall mode with PDR and CDR you are producing data and insights much sooner, this is the agile way. We don't ask for perfection, and its okay to make mistakes, simplifying assumptions etc... the point is that with each sprint the depth of analysis, breadth of insights and quality and impact that you can get by mid-May will improve ..
- 12. We have submitted an NOI for the NASA BAA with a focus on the refueling (and logistics) element where we will propose a CLIN Base Study to look at the refueling element, in the context of the larger lunar architecture set. The draft title of the proposal is: "Tentative Proposal Title: Architecture and Design Refinement of a Cryogenic Lunar Refueling and Logistics Element with planned Reusability Strategy from Moon to Mars". We may get an industrial partner as a sub to support us. This is TBD
- 13. Some have asked if you are now supposed to do the BAA proposal "instead" of the original plan for sprint 2 and 3 written in the syllabus. The answer is not really. While it is true that we did not know about or intent to participate in the BAA two weeks ago at the start of the semester, the topic of the BAA, i.e. lunar architecture analysis for human landing systems, is exactly in line with the topic of the class. The intention is that a large percentage, ideally 100% of your sprint 3 deliverable (demo 3 date: 20 March) will be simply submitted as MIT's proposal on 25 March to NASA. We feel that linking your work in 16.89/IDSS.339 in Agile Mode to a real customer and BAA opportunity is a great real life learning opportunity in itself.
Besides the above comments we have been impressed how this team has already come together and started to "click" during the first sprint.
Don't hesitate to ask questions, post things on XLP, email us... talk at lectures and work sessions as the work and learning evolve.
Cheers
Prof. Olivier de Weck MIT | deweck@mit.edu Product Owner 16.89/IDS.339