Course Overview/Design Project

Transcription

1 Course Overview/Design Project Lecture #01 August 30, 2012 Course Overview Goals Web-based Content Syllabus Policies 2012/13 Design Projects David L. Akin - All rights reserved

2 Contact Information Dr. Dave Akin Space Systems Laboratory Neutral Buoyancy Research Facility/Room 2100D

3 Goals of ENAE 483/484 (and 788D) Learn the basic tools and techniques of systems analysis and space vehicle design Understand the open-ended and iterative nature of the design process Simulate the cooperative group engineering environment of the aerospace profession Develop experience and skill sets for working in teams Perform and document professional-quality systems design of focused space mission concepts 3

4 Outline of Space Systems ENAE 483/788D (Fall) Lecture style, problem sets and quizzes Design as a discipline Disciplinary subjects not contained in curriculum Engineering graphics ENAE 484 (Spring) Single group design project Externally imposed matrix organization Engineering presentations Group dynamics Peer evaluations 4

5 But... (Recent Changes) Emphasize project content Start 484 project at beginning of 483 Build teams for spring term in the fall Add specific lectures for project specialties Provide opportunities for both experimentalists and theoreticians Design/Build/Test/Evaluate Space equivalent to design/build/fly for aero side Parallels mission-level design activities Major system(s) relevant to national programs 5

6 Web-based Course Content Data web site at Syllabus and course information Lecture notes Problems and solutions Collaboration site and lecture videos at elms.umd.edu (Blackboard) Akin s Laws of Spacecraft Design at 6

7 Akin s Laws of Spacecraft Design - #1 Engineering is done with numbers. Analysis without numbers is only an opinion. 7

8 Overview of the Design Process Program Objectives System Requirements Vehicle-level Estimation (based on a few parameters from prior art) Basic Axiom: Relative rankings between competing systems will remain consistent from level to level Increasing complexity Increasing accuracy System-level Estimation (system parameters based on prior experience) Decreasing ability to comprehend the big picture System-level Design (based on disciplineoriented analysis) 8

9 Akin s Laws of Spacecraft Design - #3 Design is an iterative process. The necessary number of iterations is one more than the number you have currently done. This is true at any point in time. 9

10 Syllabus Overview Fundamentals of Spacecraft Design - Principles and tools of Systems Engineering - Vehicle-level design - Systems-level estimation Component Detailed Design - Crew systems - Avionics - Power, Propulsion, and Thermal Analysis - Loads, Structures, and Mechanisms Team Projects 10

11 Syllabus 1: Fundamentals of Space Systems Systems Engineering Space Environment Orbital Mechanics Engineering Graphics Engineering Economics Design Case Studies 11

12 Syllabus 2: Vehicle/System-Level Design Rocket Performance Parametric Analysis Cost Estimation Reliability and Redundancy Confidence, Risk, and Resiliency Mass Estimating Relations Resource Budgeting 12

13 Problem Sets Each of the Systems Design lectures (during the first third of the course) will have associated problem sets These problem sets will form the knowledge basis for the midterm exam 13

14 Syllabus 3: Component-Level Design Loads, Structures, and Mechanisms Loads Estimation Structural Analysis Structures and Mechanisms Design Propulsion, Power, and Thermal Propulsion System Design Power System Design Thermal Design and Analysis Avionics Systems Attitude Dynamics/Proximity Operations Data Management; GN&C Communications 14

15 Syllabus 4: Component-Level Design Crew Systems Space Physiology Human Factors and Habitability Life Support Systems Design Other Topics Case studies (e.g., last year s project) Special lectures for this year s project(s) 15

16 Team Design Exercises Each of the four specialty areas will have an associated design project This will be performed by teams of 4-5 students - I will assign people to each team The results of the design exercise will be submitted as presentation slides (PowerPoint or equivalent) Team grades will be assigned for each design exercise, including adherence to the principles of the engineering communications lecture 16

17 Course Syllabus Maintained on web site (follow links or 483F12/483F12.index.html) Contains links to reference material, problem sets, solution sets, team project details, etc. Notes and announcements will be posted at top of syllabus page as necessary Every class has associated homework content; every homework has a full solution set posted after homework due date 17

18 Fall 2012 Initial Syllabus (1) 18

19 Fall 2012 Initial Syllabus (2) 19

20 Grading Policies Grade Distribution 20% Homework Problems 20% Midterm Exam 30% Team Design Exercises* 30% Final Exam Late Policy On time: Full credit Before solutions: 70% credit After solutions: 20% credit * Team Grades 20

21 A Word on Homework Submissions... Good methods of handing in homework Hard copy in class (best!) Scanned copies via (please put ENAE483 or ENAE788D in subject line) Methods that don t work so well Leaving it in my mailbox (particularly in EGR) Leaving it in my office Spreadsheets or.m files Handing it to me in random locations Handing it to Dr. Bowden 21

22 A Word about Homework Grading Homework is graded via a discrete filter for homework problems which are essentially correct (10 pts) - for homework with significant problems (7 pts) -- for homework with major problems (4 pts) + for homework demonstrating extra effort (12 pts) 0 for missing homework A detailed solution document is posted for each problem after the due date, which you should review to ensure you understand the techniques used 22

23 Selection of Class Projects Criteria - needs to be a significant engineering challenge of relevance to the current or future space program requiring the use of tools from 483 and prior classes and of appropriate scope for this class. Preferable to be appropriate for entry into design competitions My personal preference is to look at topical issues and pursue options not currently being considered in detail by NASA 23

24 NASA s Space Exploration Program Developing Saturn V-class launch vehicle ( Space Launch System or SLS) and 4-person spacecraft ( Multi-Purpose Crewed Vehicle or MPCV) SLS will cost between $20B and $40B, starting at 70 MT payload and evolving to 130 MT No human flights until ~2020; start developing lunar landing vehicle then - first human lunar landing probably

25 Logistics and Operations versus Heavy Lift: Examining Approaches to Human Exploration in a Cost-Constrained Era David L. Akin AIAA Paper Space 2011 Conference Space Systems Laboratory

26 Amundsen-Scott South Pole Station 26 Space Systems Laboratory

27 Logistics Support for Station Construction 24,000,000 pounds of hardware and consumables Flown in on 925 flights of existing LC-130 cargo aircraft Mean average temperature -47 C <100 working days/year Program cost $153M 27 Space Systems Laboratory

28 Parallels in Transport Systems? LC ,800 kg payload Delta IV Heavy 23,000 kg payload to LEO 9980 kg to LTO 28 Space Systems Laboratory

29 Study Phase 1 Summary AIAA Paper , SpaceOps 2010 Assumptions: Delta IV Heavy only In-space use of storable hypergolics only No propellant depots or transfers Keep annual funding $3B Focus of study effort Feasibility of modular vehicle performance for lunar landing Assessment of cost benefits of large production and flight rates 29 Space Systems Laboratory

30 Notional Program Elements Lunar Landing Module (LLM) 6950 kg Crew Vehicle 4990 kg 30 Orbital Propulsion Module (OPM) 6950 kg Space Systems Laboratory

31 Single Launch Lunar Cargo Mission Landed Cargo 1890 kg 31 Space Systems Laboratory

32 LLO Staging for Human Lunar Landing 32 Space Systems Laboratory

33 Notional Vehicle in Landing Configuration 33 Space Systems Laboratory

34 Comparison of Lunar Landing Vehicles 34 Space Systems Laboratory

35 Results of Phase 1 Study Use direct injection into Lunar transfer orbit and perform all in-space operations in low Lunar orbit (LLO) Develop three vehicles based on LTO payload of DIVH and mutual performance Orbital Maneuvering Stage (OMS) Terminal Landing Stage (TLS) Crew Module Adapt standard modules to specific missions through multiple stages, offloading propellant 35 Space Systems Laboratory

36 Year-by-Year Program Costs 36 Space Systems Laboratory

37 Study Phase 2 Summary AIAA Paper , Space 2010 Assumptions: Mixed launch fleet (Delta IV Heavy and Atlas 402) In-space use of storable hypergolics only No propellant depots or transfers Keep annual funding $3B Focus of study effort Probabilistic risk analysis of multilaunch missions Cost incorporation of (limited) multiple launch vehicles 37 Space Systems Laboratory

38 Monolythic vs. Modular Reliability 38 Space Systems Laboratory

39 Design Reference Mission 39 Space Systems Laboratory

40 Annual Program Expenditures 85% Learning Curve used for all repetitive production 40 Space Systems Laboratory

41 Focus of This Study (Phase 3) Improve accuracy of vehicle design estimates Incorporate mass dependence of stage inert mass fraction Investigate sensitivity to specific impulse assumptions Revisit lunar architecture with revised vehicle parameters Extend architecture to near-earth objects (NEOs) and Mars orbit destinations Perform trade studies for phased introduction of additional technologies 41 Space Systems Laboratory

42 Cost Sensitivity to Vehicle Size 42 Space Systems Laboratory

43 Sensitivity to Specific Impulse 43 Space Systems Laboratory

44 LLM OPM Comparison of New Module Parameters 44 Space Systems Laboratory

45 Lunar Cargo Mission Performance 45 Space Systems Laboratory

46 Human Lunar Landing Configuration 46 Space Systems Laboratory

47 Implications of Parametric Resizing Reduced OPM performance eliminates singlemodule lunar ascent option Two OPMs landed for ascent with partial fueling in first stage Both OPMs are single failure points for ascent Since abort-to-orbit option exists throughout descent, no change in crew safety for that phase, but additional risk to mission success Introduce option for larger vehicles assume Falcon Heavy availability (16,000 kg to TLI) 47 Space Systems Laboratory

48 OPM Parameters for FH Variant 48 Space Systems Laboratory

49 Lunar Landing Configuration Options 49 Space Systems Laboratory

50 Assessment of FH Module Options Use of OPM-F for ascent propulsion provides maximum reliability Either of the last two options (all OPM-F or all OMP-F/LLM-F) provide human lunar surface missions with six launches, and are acceptable for lunar exploration program 50 Space Systems Laboratory

51 Future Work Better graphics! Detailed design of vehicles (crew module, propulsion modules) Perform analysis for forward-staging modules in low Martian orbit for cargo and human Mars surface access Perform reliability and costing analyses for NEO and Mars cases Develop overall program design incorporating phased development of additional capabilities (Falcon Heavy modules, LEO staging modules, LOX/LH2 stages) into active mission model with budget caps Consider additional advanced technologies (orbital depots, aerobraking, reusability) for future missions 51 Space Systems Laboratory

52 Conclusions Use of simple existing technologies still provides early, affordable, repeatable human access to the lunar surface More conservative vehicle estimates support use of larger launch vehicles if available Deep space missions should be staged in LEO Long-duration LOX/LH2 stages facilitate NEO missions and are highly advantageous for Mars An evolutionary program concept using on-orbit staging will provide a robust, ongoing human exploration program without waiting for the development of super-heavy lift vehicles 52 Space Systems Laboratory

53 A Few Additional Notes All of these papers are posted on the web site under Lecture #01 Fourth paper in the series in preparation for AIAA Space 2012 conference; preprint will be available next week This material is presented only as point of departure (POD); it is to provide some initial guidance, not to be accepted as gospel I expect the 42 of you to go into much greater depth of design analysis than I did on my own! 53

54 Organization of the Design Project You will be divided into three cooperating teams: Human spacecraft design team Transportation design team Surface systems design team There will also be a program-level systems integration and mission planning team All of the design projects this term will be directly applicable to the capstone project for

55 Design/Build/Test/Evaluate Hardware design, fabrication, and testing will be an integral part of the 484 capstone project A requirement for this term is to figure out what you re building next term Choice is based on Getting design data unobtainable by analysis (e.g., human factors evaluation of crew capsule interior) Enabling meaningful mission simulations Providing value for competitions Leveraging facilities and infrastructure of SSL 55

56 End Goal: RASC-AL Competition 56

57 Matrix Organization Each project team is divided into six specialty groups Systems Integration (SI) Mission Planning and Analysis (MPA) Loads, Structures, and Mechanisms (LSM) Power, Propulsion, and Thermal (PPT) Crew Systems (CS) Avionics and Software (AVS) You will be assigned to a project and a specialty group - but you do get to express your preferences 57

58 Systems Integration Overall coordination of design activities Creation and tracking of budgets, particularly mass and cost Maintenance of canonical system configuration documents Vehicle- and system-level trade studies Cost estimation Tracking of vehicle center of gravity and inertia matrix Advanced technology (e.g., robotics, EVA) 58

59 Mission Planning and Analysis Creation and maintenance of design reference mission(s) (DRM) Orbital mechanics and launch/entry trajectories Determination of operational mission objectives Concept of operations (CONOPS) Programmatic planning (sequence of missions) Science instrument/payload definition 59

60 Loads, Structures, and Mechanisms Identification and estimation of loads sources Structural design and analysis Selection of structural shapes and materials Stress modeling Deformation estimation Design optimization Design of mechanisms (docking/berthing ports, separation mechanisms, launch holddowns, engine gimbals)) Tracking of critical margins of safety 60

61 Power, Propulsion, and Thermal Electrical power generation Energy storage Power management and conditioning Primary propulsion (orbital maneuvering) Reaction control system (rotation/translation) Design of propellant storage and feed systems Thermal modeling and analysis Thermal control systems Power budgets 61

62 Crew Systems Internal layout Emergency egress systems Lighting and acoustics Window and viewing analysis Life support systems Air revitalization Water collection and regeneration Cabin thermal control Waste management Food and hygiene EVA accommodations 62

63 Avionics and Software Data management (flight computers) Networking Sensors Power distribution Guidance system Control systems, including attitude control Communications Robot control systems Software Data transmission budgets 63

64 Akin s Laws of Spacecraft Design - #16 The previous people who did a similar analysis did not have a direct pipeline to the wisdom of the ages. There is therefore no reason to believe their analysis over yours. There is especially no reason to present their analysis as yours. 64

65 Akin s Laws of Spacecraft Design - #17 The fact that an analysis appears in print has no relationship to the likelihood of its being correct. 65

66 ENAE 788D Design Project 2012 Grad students will form a team for the four design projects throughout the term Grads will also perform systems analyses and mission design for the same lunar program for the 484 capstone project Grads will complete their project and give a final presentation on their results on the last day of the term 66

67 Akin s Laws of Spacecraft Design - #35 (de Saint-Exupery's Law of Design) A designer knows that he has achieved perfection not when there is nothing left to add, but when there is nothing left to take away. 67

68 Documentation In a group of 42 people, there are 861 possible communication paths between two people Results and decisions you make will inevitably affect everyone else in the team The 484 final report should be a comprehensive documentation of everything all 42 of you did on the project over this academic year Document! Use archival electronic media (forums and postings on Blackboard) rather than informal (chat rooms, texts, s) If I can t see it, you don t get credit for it 68

69 Akin s Laws of Spacecraft Design - #22 When in doubt, document. (Documentation requirements will reach a maximum shortly after the termination of a program.) 69

70 Closing Comments Focus on numerical analysis and systems engineering this is not hardware-bashing Look for your own design solutions this is also not catalog shopping Approach everything rigorously with numbers this is also also not adjective engineering Manage scope and risk along with cost, mass, and other design parameters Be innovative, while remaining real What you get out of the process is directly proportional to what you put in 70

71 Today s Assignment Download and read the POD papers from the spacecraft web site Watch the clip on the design of the Apollo Lunar Module from the episode Spider from the miniseries From the Earth to the Moon (posted) Do assignment posted on spacecraft.ssl.umd.edu under Lecture #01(due Thursday 9/6) 71

72 Akin s Laws of Spacecraft Design - #9 Not having all the information you need is never a satisfactory excuse for not starting the analysis. 72