The system design phase had the sole purpose of coming up with an overall concept or idea for the project. With an agreed upon concept, this will lead us into the next phase where we start design the subsystems and making them more detailed/specific.
Team Vision for System-Level Design Phase
GoalsOur goals for this phase of the project included several stepping stones. We wanted to come up with several concepts for the project, but begin to shorten the list and begin to choose the top concept ideas. Learn possible risks involved with the design and assess the possible ways to fix them; find some new benchmarks for components and subsystems Identify the functions and the smaller components of each function. Creating some examples of numbers and feasibility on ideas. Another goal we have set for ourselves is to talk to a contact at Boeing and just get some feedback and specs from the company itself.
AccomplishmentsWe were able to complete many of our goals. The concept ideas were evaluated and the top two concepts are the first and third one. Risks were discovered and possible solutions were created and the benchmarks were added such as the microcontrollers. We learned more about the overall functions of our entire system and have been coming up with several feasibility analyses.
OtherWe have not contacted anyone at Boeing yet due to us wanting to get input from our customer (Dr. Day).
Functional DecompositionFunctional Decomposition Chart
Concept DevelopmentConcept Idea 1
Morphological Chart and Concept SelectionMorphological Chart Visual Morphological Chart
Criteria for Concept Selection
- Uses magnets for levitation
- Can it operate underwater
- Is it safe
- Are there shafts and seals
- Will Boeing be able to adopt the design
- High flow of water
- Is it completely waterproof
- Is it stable
- Keeps propeller and user safe
- Not an electrical hazard
- Programming is efficient and robust
- Can be completed in 2 semesters
- Easy to use
- Cheap to produce
- Generates a lot of thrust
- Friction-less and no mechanical wear
- Full levitation could potentially be very difficult to achieve so the gift shop design (concept 2) is our primary fallback.
- Another fallback would be to make a partially levitated propeller that only has 1 mechanical point.
- Ideally the final design would be submersible, but it would be beneficial to get the propeller working in air and not worrying about the waterproofing unless we have time to do it.
Concept SelectionPugh Charts
The Magnetically Levitated Propeller design will be comprised of several mechanical and electrical systems:
- Axial magnetic levitation and stability system
- Lateral magnetic (or mechanical) stability system
- Propeller rotation mechanism (electromagnetic or mechanical)
- Propeller physical protection system
- Propeller case/duct system
- Electronic control system for electromagnet and propeller operation
- Electronics and magnetics waterproof housing
- User controller interface
Feasibility: Prototyping, Analysis, Simulation
Question: How will thrust be calculated?
- is a function of vehicle speed
- incompressible fluid & flow
- exit velocity is uniform
- gain data from test runs
Analysis: Note: We have not reached the phase to actually do calculations of thrust on a the propeller, so these will be the steps or ideas needed to solve it. Choose a method for calculating thrust
- Direct thrust measurement - Force balance
- Calculations based on velocity profiles - Bernoulli's equation & Reynold's number will be useful
- Sample equation
- Online thrust calculators: static thrust calculator & NASA's TC Logger
- F is the force/thrust
- P is the pressure, Pte is the downstream total pressure, Pto is the static pressure
- p is the density of air or water (vicinity it is in)
- Ve is the exit velocity, Vo is velocity of the vehicle
- A is the disk area of the propeller
By Bernie Garcia
Question: What material and structure is most appropriate for the propeller?
- Natural magnets can be easily integrated into design
Analysis: Research and comparison of various commonly-used propeller materials. See which would be easiest to integrate magnetic design and system.
Shown below is a boat propeller material comparison from Eris Propellers. Link to website is provided under Design Review Materials section.
By Mike Purcell
Question: What forces/strength values are the normal outputs of rare earth magnets? (In general) Alternatively, how much force do rare earth magnets exhibit?
- No losses seen by magnetic field due to outside forces
- Measurements are made at normal conditions ( temp, pressure, humidity, etc.)
- Magnetic field caused by rare earth magnets is constant disc/cylinder magnets
As shown by the chart, as the separation distance decreases, the magnetic attraction force increases. Likewise, our end goal is to decrease the separation distance between two or more earth magnets (neodymium) in order to maximize the attraction force between such magnets.
By Joe Bernardini
By Elijah Sensenig
By Zach Louison
Designs and Flowcharts
Design Review Materials
- Reference to Propeller Thrust Data *NASA's property: https://www.grc.nasa.gov/www/k-12/airplane/propth.html
- Reference to Propeller Analysis *NASA's property:http://www.grc.nasa.gov/WWW/K-12/airplane/propanl.html
- Reference to Eris Propeller material comparison site page:
- Reference to general maglev overview: https://www.kjmagnetics.com/blog.asp?p=maglev-train
- Transrapid maglev field strength reference: http://www.transrapid.de/cgi-tdb/en/basics.prg?a_no=50
- BBC article regarding maglev trains: http://www.bbc.com/future/story/20120504-the-floating-future-of-trains
- Active magnetic bearing overview: http://www.calnetix.com/powerflux-active-magnetic-bearings
- The customer requirements and engineering requirements document can be found here
- The house of quality can be found here
- A copy of this phase's review can be found here