Page 1
Edward White, Aerospace Engineering, Texas A&M University, Instruction in Experimental Methods Session, AIAA ASM 2007
Laboratory experiences in a mechanical and aerospace engineering departmentEdward White - [email protected]
Aerospace Engineering, Texas A&M University
Until recently - Mechanical and Aerospace Eng.,
Case Western Reserve University
Page 2
Edward White, Aerospace Engineering, Texas A&M University, Instruction in Experimental Methods Session, AIAA ASM 2007
What to do (and what canbe done) in undergraduatelab courses
Edward White - [email protected]
Aerospace Engineering, Texas A&M University
Until recently - Mechanical and Aerospace Eng.,
Case Western Reserve University
Page 3
Edward White, Aerospace Engineering, Texas A&M University, Instruction in Experimental Methods Session, AIAA ASM 2007
Undergraduate lab instruction should produce competent producers and consumers of experimental results.
Page 4
Edward White, Aerospace Engineering, Texas A&M University, Instruction in Experimental Methods Session, AIAA ASM 2007
We who hire new grads need them to to start work or grad. school ready to make meaningful contributions.
Page 5
Edward White, Aerospace Engineering, Texas A&M University, Instruction in Experimental Methods Session, AIAA ASM 2007
How should we structure laboratory instruction to achieve this?
Maximum exposure?Stressing fundamentals?Something in between?(What about demos for other courses?)
There’s limited time, credit hours and attention. We can’t do it all.
Page 6
Edward White, Aerospace Engineering, Texas A&M University, Instruction in Experimental Methods Session, AIAA ASM 2007
The right balance prepares students to make meaningful contributions in the widest range of applications and roles over the span of their careers
Page 7
Edward White, Aerospace Engineering, Texas A&M University, Instruction in Experimental Methods Session, AIAA ASM 2007
To achieve this, we shouldstress thoughtful application ofkey principles, not maximum exposure to state-of-the-art instruments or rapid-fire labs
Page 8
Edward White, Aerospace Engineering, Texas A&M University, Instruction in Experimental Methods Session, AIAA ASM 2007
Why emphasize key principles over introduction state of the art?
Page 9
Edward White, Aerospace Engineering, Texas A&M University, Instruction in Experimental Methods Session, AIAA ASM 2007
Key principles have enduring value; the state of the art is ever changing.
So, use limited time and resources where they’ll have the best and broadest long-term impact.
Page 10
Edward White, Aerospace Engineering, Texas A&M University, Instruction in Experimental Methods Session, AIAA ASM 2007
Students’ capability to absorb and competently apply new concepts is limited.
Capture Efficiency Delivery Rate -(1+)
Page 11
Edward White, Aerospace Engineering, Texas A&M University, Instruction in Experimental Methods Session, AIAA ASM 2007
There’s limited time in lectures, lab sessions
Students have limited time(typically enrolled in 4-5 other courses)
I have limited time.
Page 12
Edward White, Aerospace Engineering, Texas A&M University, Instruction in Experimental Methods Session, AIAA ASM 2007
There’s limited time in lectures, lab sessions
Students have limited time(typically enrolled in 4-5 other courses)
I have limited time.
Page 13
Edward White, Aerospace Engineering, Texas A&M University, Instruction in Experimental Methods Session, AIAA ASM 2007
There’s limited time in lectures, lab sessions
Students have limited time(typically enrolled in 4-5 other courses)
I have limited time
Page 14
Edward White, Aerospace Engineering, Texas A&M University, Instruction in Experimental Methods Session, AIAA ASM 2007
The state of the art is expensive!
Page 15
Edward White, Aerospace Engineering, Texas A&M University, Instruction in Experimental Methods Session, AIAA ASM 2007
Why emphasize key principles over introduction state of the art?
Page 16
Edward White, Aerospace Engineering, Texas A&M University, Instruction in Experimental Methods Session, AIAA ASM 2007
Mastery of key principles is what’s required for creativity, design and technical leadership
Page 17
Edward White, Aerospace Engineering, Texas A&M University, Instruction in Experimental Methods Session, AIAA ASM 2007
What are the key principles?
Page 18
Edward White, Aerospace Engineering, Texas A&M University, Instruction in Experimental Methods Session, AIAA ASM 2007
(1) Every measurement is uncertain and the uncertainty must be understood and quantified
Page 19
Edward White, Aerospace Engineering, Texas A&M University, Instruction in Experimental Methods Session, AIAA ASM 2007
There’s subtlety and difficulty in making even simple measurements
Page 20
Edward White, Aerospace Engineering, Texas A&M University, Instruction in Experimental Methods Session, AIAA ASM 2007
There’s not a “right” answer on which to fall back (although one should have a pretty good guess before starting)
Page 21
Edward White, Aerospace Engineering, Texas A&M University, Instruction in Experimental Methods Session, AIAA ASM 2007
There’s almost always a variety of means of making a measurement
Page 22
Edward White, Aerospace Engineering, Texas A&M University, Instruction in Experimental Methods Session, AIAA ASM 2007
Instruments and techniques must be calibrated against known, reliable standards
Page 23
Edward White, Aerospace Engineering, Texas A&M University, Instruction in Experimental Methods Session, AIAA ASM 2007
What are the key principles?
Page 24
Edward White, Aerospace Engineering, Texas A&M University, Instruction in Experimental Methods Session, AIAA ASM 2007
(2) Instruments and techniques consist of “knowable” components that can be understood, critiqued, and improved upon by undergraduates.
There should be no black boxes.
Page 25
Edward White, Aerospace Engineering, Texas A&M University, Instruction in Experimental Methods Session, AIAA ASM 2007
Instruments consist of multiple simpler components
Page 26
Edward White, Aerospace Engineering, Texas A&M University, Instruction in Experimental Methods Session, AIAA ASM 2007
Computers do repetitive things quickly.
They don’t do things correctly (necessarily) they do things quickly.
Page 27
Edward White, Aerospace Engineering, Texas A&M University, Instruction in Experimental Methods Session, AIAA ASM 2007
What are the key principles?
Page 28
Edward White, Aerospace Engineering, Texas A&M University, Instruction in Experimental Methods Session, AIAA ASM 2007
(3) There’s nothing useful about knowing something if you can communicate it in a clear and convincing way
Page 29
Edward White, Aerospace Engineering, Texas A&M University, Instruction in Experimental Methods Session, AIAA ASM 2007
Ultimately, mastery of these key principles of experimental work comes through practice and application.
What do we actually do?
Page 30
Edward White, Aerospace Engineering, Texas A&M University, Instruction in Experimental Methods Session, AIAA ASM 2007
Perform a few “simple” labs that teach the key principles by requiring clear thinking about a tractable problems
Page 31
Edward White, Aerospace Engineering, Texas A&M University, Instruction in Experimental Methods Session, AIAA ASM 2007
Along the way we teach about data analysis and simple instrumentation as well as demonstrate physical principles to enhance other courses
Page 32
Edward White, Aerospace Engineering, Texas A&M University, Instruction in Experimental Methods Session, AIAA ASM 2007
Page 33
Edward White, Aerospace Engineering, Texas A&M University, Instruction in Experimental Methods Session, AIAA ASM 2007
Page 34
Edward White, Aerospace Engineering, Texas A&M University, Instruction in Experimental Methods Session, AIAA ASM 2007
Page 35
Edward White, Aerospace Engineering, Texas A&M University, Instruction in Experimental Methods Session, AIAA ASM 2007
Often
Solid Strain Basic UncertaintyMech. Gages Prop. Of Errors
Computerized DAQ
Heat TC’s Linear RegressionTrans.
Fluid Hot Fourier AnalysisMech. Wires
Page 36
Edward White, Aerospace Engineering, Texas A&M University, Instruction in Experimental Methods Session, AIAA ASM 2007
Example Lab
Measure the pressure in an unopened pop can.
Page 37
Edward White, Aerospace Engineering, Texas A&M University, Instruction in Experimental Methods Session, AIAA ASM 2007
Mayhem ensues.
Functional groups’ p’sRange from 15 to 100 psi.
All groups have different p’s for the axial and circumferential gages.
Some groups have a gage break, need to improvise.
All have definite opinions about whether this is a good way to measure pressure!
Most groups are able to make interesting conclusions about what went right and what went wrong.
What’s the result?
Page 38
Edward White, Aerospace Engineering, Texas A&M University, Instruction in Experimental Methods Session, AIAA ASM 2007
This is a simple experiment:Simply put some gages on a can and open it.
But, it’s actually a rich, complex (but tractable) problem that uncovers a huge range of real experimental issues.
Page 39
Edward White, Aerospace Engineering, Texas A&M University, Instruction in Experimental Methods Session, AIAA ASM 2007
This is the sort of foundation from which we should build.
Don’t underestimate the rigor that’s needed even for simple things
Understand and dissect the process
Understand uncertainty
Page 40
Edward White, Aerospace Engineering, Texas A&M University, Instruction in Experimental Methods Session, AIAA ASM 2007
Use this and a few other practice examples of similar scope, then move on to the more complex, more modern work.