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Gateway To Space ASEN 1400 / ASTR 2500 Class #17. T -39. Colorado Space Grant Consortium. Today:. Announcements One Minute Report Questions Guest Lecture on Systems Engineering. Announcements:. Hardware for teams… Pressure sensors and other hardware UNO $$$
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Gateway To Space ASEN 1400 / ASTR 2500 Class #17 T-39 Colorado Space Grant Consortium
Today: • Announcements • One Minute Report Questions • Guest Lecture on Systems Engineering
Announcements: • Hardware for teams… • Pressure sensors and other hardware UNO $$$ • Latest grades posted later today • Feedback on DD Rev A/B next Tuesday • DD Rev C assigned today and due 11-16-12 • Don’t forget about HW #8 – Review it first
Announcements: • Traveling tomorrow – Planned • Guest speaker is not coming – Not Planned • So tomorrow is…
Next Time… Spider Plus remote introduction (Originally the lecture scheduled for November 15th) Colorado Space Grant Consortium
One Minute Report Questions: • What kind of rocket is Dreamchaser? • What is Dreamchaserused for? • Where do dropped engines go? Orbit, outerspace? • Biggest advance from past to present rockets? • Do all space programs work together now? • How do private companies get funded?
One Minute Report Questions: • Why do they chose solid vs. liquid, vs. hybrid? • As an aerospace major, how well versed should I be with coding/programming? • What happened to the Orion space missions? • What does the future of space exploration look like?
Questions? Colorado Space Grant Consortium
Homework #7 Review Colorado Space Grant Consortium
Homework #7: NASA Mission Announcement – ChuSat Design a spacecraft in 30 minutes that will meet the following two requirements: 1. The total mass of the power, science instruments, and propulsion shall not exceed 900 lbm. a. The propulsion mass shall include the mass of propellant
Homework #7: NASA Mission Announcement – ChuSat Design a spacecraft in 30 minutes that will meet the following two requirements: 2. The spacecraft shall collect a minimum of 20 hours of scientific data a. The spacecraft shall collect data in the 1x10-9 to 1x10-10 wavelengths b. The spacecraft shall collect data in the 1x10-3 to 1x10-4 wavelengths The following subsystem capabilities and specifications are at your disposal.
Homework #7 - (Answer) Science - Infrared Sensor 75 W 30 lbm - X-ray Sensor 100 W 40 lbm Total Science Mass 70 lbm If only one sensor is on at a time is the requirement of 20 hours met? Only have one sensor on at a time, therefore the Science power requirement is 100 W, not 175 W.
Homework #7 - (Answer) Power Need at least 1,000 W to stay alive plus 100 W for science therefore you need to have at least 1,200 W solar array and battery Total weight = 60 lbm for solar array = 120 lbm for battery Total = 180 lbm You will find out the Fuel cell is way too heavy
In-Class Exercise: (Answer) Propulsion Need at least 80 lb of thrust therefore you need the following Two 25 lb thrusters = 20 W 25 lbm Three 10 lb thrusters = 20 W 15 lbm Total Power = (40+60 W) = 100 W Total Mass = (25+25+15+15+15) =95 lbm
In-Class Exercise: (Answer) Total Mass Science = 70 lbm Power = 180 lbm Propulsion = 95 lbm Total = 345 lbm (minus propellant)
In-Class Exercise: (Answer) Propellant Mass 2x25 lb = 50 per/100 lbm = 100 lb 3x10 lb = 20 per/100 lbm = 60 lb Total = 160 lb per 100 lbm 345 lbm / 100 lbm * 160 lbm = 552 lbm
In-Class Exercise: (Answer) Total Mass Science = 70 lbm Power = 180 lbm Propulsion = 95 lbm Total = 345 lbm (minus propellant) Propellant = 552 lbm Total mass = 897 lbm
Systems Engineering Jessica Brown Lockheed Martin Rachel Landess Lockheed Martin Colorado Space Grant Consortium
Introduction to Systems Engineering October 23, 2012 Rachel Landess Keith Morris Jessica Brown
What is Systems Engineering • Is a systematic, interdisciplinary approach that transforms customer needs into a total system solution • A framework of interrelated activities that spans Design, Management, and Realization of systems • Balances customer needs with system capabilities • Led and organized by Systems Engineers • But all functions play a role • It is the technical “glue” which makes separate design disciplines and subsystems function together to provide an integrated system
Be a “Systems Thinker” • The Design Engineer • The specialist's viewpoint • Views the system from the inside • Concerned with other system elements only as they affect their own design task • Not necessarily how their system may affect others • Systems thinkers • Views the system from the outside. • Concerned with the effect of all system elements as they affect overall system design / performance / cost / schedule • Concerned no matter where the hole in the boat is
Systems Engineering must focus on the entire problem: optimize the whole, not the parts!
The Art & Science of Systems Engineering • Art of Systems Engineering • Technical Leadership • Understanding how all the individual pieces go together to make the big picture • Science of Systems Engineering • Systems Management • Managing all the details for every piece of the system and keeping them in synch • Cost, Schedule, Performance, & Risk To be Successful, we must balance both technical leadership and systems management into complete systems engineering
Architecture • System Architecture is the overall structure of the program, internal interfaces, and how it interacts with external interfaces • System Level – Constellation of Satellites, Ground stations, etc. • Spacecraft Level – Subsystems and interfaces that make up spacecraft • Subsystem – Components and technologies that make up subsystem • Architect’s role is to ensure customer requirements and needs are properly addressed in the system • Identifies utility and flexibility of the system • Optimizing architecture can make spacecraft trades easier
Spacecraft Architecture (image credit: NASA/GSFC)
Concept of Operations • Concept of Operations (CONOPS) • How the system will be used • Links technical requirements with user’s needs • Requirements do not fully represent customer’s wishes… • Operational scenarios, timelines, block diagrams, orbital maneuvering among the products • Example: Assignment Requirements do not specify how often payloads need to operate, could reduce overall power required
Requirements Management • A requirement is a “single, verifiable shall statement” • Requirements dictate the form, fit and function the system design shall meet • Requirements address both characteristics as well as capabilities • Characteristics=what the system shall be • Capabilities=what the system shall do • Higher level requirements are decomposed to lower level requirements
Why are requirements important How the project manager understood it How the engineers designed it How the customer explained it How the customer really wanted it How materials ordered it How it was built Clearly communicating requirements is essential
Design Integration • Balance the needs of the customer with the capabilities of the spacecraft • Balance the needs of the individual subsystems • Allocate mass, volume, power constraints • Relate it to their assignment • Ensuring subsystems are talking with one another • Making sure they are compatible • Identifying subsystem interfaces Its kind of like Herding Cats
Risk Management • Risk management is done throughout the entire program life cycle • Risk is defined in two dimensions • Probability of occurrence • Consequence if the risk occurs • Identify risks while there is still time to react • Put in place mitigation strategy to minimize or eliminate risks • Sources of risks include: • Poorly defined technical tasks or cost estimations • Poorly defined requirements and interfaces • Low technological maturity (technical risks) • Unrealistic project planning or inadequate resources • Inadequate workforce skill level Risk Matrix Probability of Occurrence Consequence
Hardware Integration • Assembly of spacecraft hardware Spitzer Space Telescope from design to integration
Verification and Validation • Verification • “Did we build the system right” • Validation • “Did we build the right system” • System Testing • Functional tests • Vibe tests (drop tests) • Shock tests (swing tests) • Thermal Vacuum tests • Acoustic tests ALL-STAR and team at vibe test at Lockheed Martin
Mission Operations • Starts when spacecraft development is initiated and continues through final disposal of space asset • Provide mission requirements support for development of operational systems • Used to plan and control launch vehicle and spacecraft operations • Developing mission profiles, operational procedures and related operational documentation • Balance and allocate operational requirements with operational performance • Determine operations integration tasks • Defining capabilities and constraints associated with launch vehicles, spacecraft and mission control and ground systems
Summary • Systems Engineering is an integrated composite of people, products, and processes • Forms a structured development process • Spans design, production, and operation of systems • Balances the needs of the customer with the capabilities of the system • Uses technical leadership and systems management • Integrates all disciplines and specialty groups into team • Manages cost, schedule, performance, and risk • There is no perfect solution • Systems engineering produces the optimal solution for the entire spacecraft