MECH 322 Instrumentation

1
MECH 322 Instrumentation

• Goals
• 2007 Format
• Ideas for next year
• Course Evaluation

2
My Goals

• Observe and measure important physical phenomena
• manometers, beam bending, venturi and Pitot
  probes, boiling water temperature, HTC dependence
  on conductivity, damped vibration, Karman vortex,
• Signal noise, aliasing, feedback control
• in lab frequently observe things you didnt
  expect, troubleshooting
• Understand theory behind and feel comfortable
  using instruments, computerized data acquisition
  and control systems

3
My Goals

• Perform steady and transient measurements,
  understand potential errors (bias, random,
  transient)
• Communicate
• Use clear tables and charts to present
  engineering data
• Analyze and draw bulleted conclusions based on
  data
• Prepare for senior labs and professional practice
• Reasonable work load, so focus

4
Focus Each Lab had Stages

• Clear handouts and lectures (I tried!)
• Web Site easy materials access
• Lab Preparation Homework and Sample Reports
• Revised each year, intended to
• help students know what is expected
• simplify lab time confusion
• LabVIEW programming by example, not theory
• Write reports in lab
• Analyze soon after data acquisition (allows
  re-acquisition)
• give student access to instructor help
• Bulleted conclusion format
• Outlines formal reports (prepare for senior year)

5
5 Statistical Methods Labs

• UNR Quad Measurement
• Find grass seed cost and uncertainty, very
  practical
• Quad Data Analysis
• Mean, St. Dev, Data Exclusion, Correlation
  Coefficient
• Wide range of results highlights need for
  calibration
• Monometer Calibration
• Calibration removes bias
• Standard Deviation of output and input quantifies
  impression
• Strain Gage Installation
• length error estimates
• Elastic Modulus Measurement
• Uncertainty in best fit slope
• Propagation of error, compare calculated to
  literature value
• Written Midterm

6
3 Steady and Data Acquisition Labs

• Air Speed and Volume Flow Rate
• Use pressure transmitters, check consistency
• Propagation of error
• Steady Temperature of Boiling Water at Elevation
• TC, LabVIEW, compare with prediction
• Numerical Differentiation and Spectral Analysis
  of Unsteady Signals
• Sampling Rate Theory, Time derivatives
• Demonstrate unsteady data processing errors and
  solutions
• Written Midterm

7
4 Unsteady Measurement Labs

• Transient Response of a Thermocouple
• Heat transfer in water and air
• uncertainty
• Vibration of a Weighted Cantilever Beam
• Natural frequency prediction and damping
• uncertainty
• Karmon Vortex Unsteady Speed
• Dynamic measurement and spectral analysis
• uncertainty
• Temperature Feedback Control
• Analog output, digital relay, logic
• Lab Practicum Final

8
New This Year

• 3 lectures/week (4 credit course)
• More contact hours
• Slowed lecture pace
• More detailed description of instrument theory
  and use
• More error analysis
• Proportional control
• Design of Experiments
• Offered discounted NI USB 6009
• But did not offer instruments
• Offered Tutorials
• Poorly attended

9
Next Year

• Offer inexpensive thermocouple signal conditioner
  and digital relay
• Buy or check out (deposit)
• Use for Boiling Water Temperature, Transient TC,
  and Control labs
• Gives students an opportunity to learn how to do
  labs at home
• Removes lab time constraint
• Gives students opportunity to explore
• Supervision and liability problems

10
EvaluationME Curriculum has 14 outcomes

• The course increased my ability to apply the
  principles of mathematics, science, and
  engineering
• Instrument models, dynamic response of TC,
  vibrating beam, error analysis
• The course increased my ability to conduct and
  design experiments, as well as to analyze and
  interpret data
• Focused on understanding and performing but not
  designing experiments
• (not applicable) The course increased my ability
  to identify and document desired needs and to
  design a system component, or process to meet
  desired needs within realistic constraints such
  as economic, environmental, social, political,
  ethical, health and safety, manufacturability,
  and sustainability

11

• The course increased my ability to function on
  multi-disciplinary teams
• Lab groups and reports with time constraint
• The course increased my ability to identify,
  formulate, and solve engineering problems
• Lab experience is always different from
  expectations, adjust conclusions based on data,
  troubleshoot problems
• The course increased my ability to explain
  professional and ethical responsibility and
  identify professional and ethical issues
• Present your data, not expectations (highlight
  differences and discuss possible reasons)
• The course increased my ability to communicate
  effectively
• Engineering tables and charts, draw bulleted
  conclusions from data (different from
  non-quantitative work), Abstract of results,
  formal citations

12
Evaluation (cont)

• (not applicable) The course enhanced my broad
  education necessary to understand the impact of
  engineering solutions in a global, economic,
  environmental, and social context
• The course increased my ability to explain the
  need for, and an ability to, engage in life-long
  learning
• New equipment, learning from manufacturer data
  sheets
• (not applicable) The course increased my ability
  to identify and analyze contemporary issues
• The course increased my ability to use the
  techniques, skills, and modern engineering tools
  necessary for engineering practice
• Measurement devises, Data Acquisition and Control
  programs

13

• (not applicable) The course increased my ability
  to apply the principles of mathematics and
  computational methods, including multivariable
  calculus and differential equations, in the
  identification, formulation, and solution of
  engineering problems.
• Instrument models, dynamic response of TC,
  vibrating beam, error analysis
• The course increased my familiarity with
  statistics and linear algebra.
• Sample mean, standard deviation, Correlation
  Coefficient, Linear Regression, Data Exclusion,
  St Dev of fit, Propagation of Error
• The course increased ability to work
  professionally in both thermal and mechanical
  systems areas, including the design and
  realization of such systems

14
Feedback

• Now
• E-mail (greiner_at_unr.edu)
• https//webct.unr.edu/

15
Course Evaluation website

• https//webct.unr.edu/
• May 2 and 3, 2007
• Two Parts
• Instructor
• Learning Outcomes

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Open Ended Lab/Design

• Revisit One Unsteady Lab
• student choice, improve or fix problems
• Transient Response of a Thermocouple
• Imbed TC in a sphere to slow down response
• Damped Vibration of a Cantilever Beam
• Rigid fixture, steel beam, different weights
• Karmon Vortex Unsteady Speed
• Packed straws at entrance to reduce unsteadiness
• Vary cylinder diameter and distance to probe
• Temperature Feedback Control
• Partial power, proportional power

17
Student Posed Labs

• Student poses a question
• Design and perform an experiment to answer it
• () More motivated self learning
• (-) Slower, more student and instructor effort
  for the same basic skills than directed study

18
Final Labs

• Lab Practicum Final
• Repeat 1 unsteady lab
• Solo
• Unassisted