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Infusing Laboratory Skills
Throughout the Physics
Curriculum
- or -
Lab HW in ALL courses
2012 Topical Conf. on Advanced Laboratories
July 25, 2012
Marty Johnston
University of St. Thomas
St. Paul, MN
How we want to see our curriculum…
How we really look…
What
We Taught
Analytical
Experimental
Computational
Communication
What We
Wanted
Analytical
Experimental
Computational
Communication
- Vs -
Our Solution… Revitalize our curriculum by Increasing the experimental,
computational and communication content in all of our courses
Departmental Mission:
Both inside and outside the classroom, the University of St.
Thomas Physics Department provides undergraduate students
with a broad understanding and appreciation for physics,
cultivates problem solving skills involving analytical,
experimental and computational techniques and teaches how to
effectively communicate technical ideas. We strive to instill
values that enable individuals to responsibly engage the world
they live in.
NOT a solo effort…
• Everyone was involved – department wide commitment key to long-term viability
• Ideas evolve –
• Patience –
it takes resources to change curriculum, both time and money
Building Skills…
Freshman Sophomore Junior Senior
Introduction
Skill Introduction (Freshman / Sophomore courses)
• CISC 130 Problem Solving and Programming in the Natural Sciences
(programming in C)
• PHYS 215 Foundations of Modern Physics
(scopes, signal conditioning, nuclear instrumentation)
• PHYS 225 Applications of Modern Physics
(modeling of systems using Matlab)
• ENGR 350 Introduction to Electronics
(analog electronics)
Pulling it together …
Freshman Sophomore Junior Senior
Introduction
Integration
Skill Integration (Sophomore / Junior courses)
• PHYS 323 Methods of Experimental Physics
(computer aided DAQ, instrumentation, data analysis)
• PHYS 347 Optics
(physical optics culminating in optical tweezers)
Putting it in practice…
Freshman Sophomore Junior Senior
Introduction
Integration
Application
Skill Application (Junior / Senior Courses)
• Laboratory and Computational Homework …
… involved but not onerous
PHYS 331 Theoretical Mechanics
PHYS 341 Electricity and Magnetism
PHYS 410 Thermodynamics and Stat Mechanics
PHYS 431 Quantum Mechanics
NSF Grant DUE-0311432 Incorporating Computer modeling into the Upper-Division Physics
PI - Paul Ohmann
MathWorks Curriculum Development Grant
PI - Marie Lopez del Puerto
Skill Application (Junior / Senior Courses)
• Transitional Undergraduate Research – grows out of coursework
Quantum Dots (PHYS 225)
Polarization and Insects (PHYS 347)
Astronomical Data Mining (PHYS 104)
Nonlinear Systems (PHYS 323)
A. Green, P. Ohmann, N. Leininger, J. Kavanaugh
Physics Teacher, Vol. 48, No 1
Labs Infused Throughout the Curriculum
Freshman Sophomore Junior Senior
Introduction
Integration
Application
Where did advanced lab go ? …
Freshman Sophomore Junior Senior
Introduction
Application
PHYS 323
Methods of
Experimental Physics
Integration
PHYS 323 Methods of Experimental Physics:
A Sophomore Level Bridge Between
the Introductory Labs
and the Upper Level Curriculum
• Build on familiar physical concepts while introducing new mathematics, instrumentation, and coding
• Learn how to communicate, discuss ethics, and develop confidence
• Topics are driven by questions that arise during the investigation
• Course built around three two one experiments
The Physical System:
A Chaotic Physical Pendulum
Builds on concepts
introduced in
classical physics
• Rotational Dynamics
• Faraday’s law & Lorentz Force
The Physical Pendulum…
Time Domain
Frequency Domain
Phase Space
The Damped Physical Pendulum…
Time Domain
Frequency Domain
Phase Space
The Physical System…damped and driven…
Time Domain
Frequency Domain
Phase Space
Poincare Section
The Physical System…damped and driven…chaotic
Time Domain
Frequency Domain
Phase Space
Poincare Section
Searching for order…
Part I – Jumping Into the Problem
(4 weeks)
Part II – Building up Instrumentation &
Basic Analysis
(7 weeks)
Part III – Exploration
(4 weeks)
Fitting it all in …
Part I - Jumping into the Problem
Introduction to LabVIEW and Data Acquisition
Hands-On Introduction to LabVIEW for Scientists and Engineers,
2nd ed. John Essick, Oxford University Press, 2012
Review of Oscillators and Differential Equations
Develop a Mathematical Model for Our System
sin ( ) cos( )f f d d
I
I rmg b t
Part II - Building up the Instrumentation and Basic Analysis
Sensing Motion
Quadrature Encoders, Buffers, and Hardware Timing
Controlling Magnitude of Torque Eddy Motor (DC motors, Hall sensors)
Producing a Sinusoidal Drive Stepper Motor and Scotch Yoke
(Digital electronics, driver circuits, error sensing)
Part II - Building up the Instrumentation and Basic Analysis
Streaming and its Derivatives …
Numerical Methods - Digital Derivatives, Savitzky – Golay Filters
Characterization of the System … Fitting Techniques
Frequency Analysis …
Fourier Techniques, Windows and Convolutions
Part II - Building up the Instrumentation and Basic Analysis
Poincare Sections …
Part II - Building up the Instrumentation and Basic Analysis
Bifurcation Diagrams …
d
Part III – Exploration (4 weeks)
Students work on a question that interests them …
… What are the predictive abilities of our model?
- VS -
Experiment Theory
Part III – Exploration
How can we quantify what we see?
Correlation Dimension
1
( )1( )
1
Ni
i
N RC R
N N
0
log ( )lim
logc
R
C Rd
R
Part III – Exploration
Is the correlation dimension stable with changes in phase?
0 20 40 60 80 100 120 140 160 180 2001.51
1.515
1.52
1.525
1.53
1.535
Dimension as a function of Phase
Cosine (1 Hz) Driving, 200 Poincare sections
Poincare Index
Poin
care
Dim
ensio
n
Part III – Exploration
Can’t we build a better stepper motor controller?
Xilinx FPGA
Part III – Exploration
How robust is our model for friction?
- vs -
sin cos( ) ( )f d dI rmg b t
sin os() c( )f f d dI rmg tb
Part III – Exploration
Is our torque really sinusoidal? What happens if it isn’t?
sin os( )( ) c df f dI rmg b t
Part III – Exploration
… Course Concludes with a Student Poster Session
Sonoluminescene…
Martian Atmosphere & Paschen Curves…
Why Chaos - what else could work?
Where are we now?
• Balance between analytical, experimental, computation and
communication is significantly improving.
• The structure for integration is in place
• Need to fully implement laboratory and computational
homework.
• Need to develop additional versions of Methods Course
Freshman Sophomore Junior Senior
Introduction Integration
Application
Where are we now?
• Realize that we will never be done! The process is what makes
us better.
Support from my students & colleagues
Eric Brost
Vy Tran
Adam Green
Jeff Jakio
funding from NSF, MN Space Grant, and UST
is gratefully acknowledged