MEGR 3171L
Project: Characterization of a Vibrating Beam
[This is a two Week Project]
Background
A cantilever is a beam anchored at only one end, Figure 1. Cantilevers are widely found
in construction, notably in bridges, balconies and highway signs. They

Uncertainty Analysis
What if our result is dependent on more than one measured variable?
Uncertainty Analysis
Suppose we measure N physical quantities (voltage, temperature, resistance, power,
torque, etc.)
Also suppose that each of these quantities has a

Stress, Strain, and Strain Gages
Stress, Strain, and Strain Gages
Example: A wire is stretched from its initial length of 0.4000 m to a length of 0.4005 m. E
of the material is 95.0 Gpa. Poissons ratio is 0.333.
a. Calculate the axial stress in units of M

Problem 4.37 from text:
Selecting a sample size
A manufacturer of general aircraft dry vacuum pumps wishes to estimate the mean failure time of a product with 95% confidence.
Initially, 6 pumps are tested to failure with the following results (in hours of

Introduction to Measurement and
Instrumentation
Introduction to Measurement and Instrumentation
Dr. Karen Thorsett-Hill
Two primary purposes of
measurements
1. Engineering Experimentation: This is where we see new
information and is generally done when de

Temperature Measurement
4 Basic Types of temperature measuring devices:
1. Mechanical
2. Thermodynamic
Temperature Measurement
4 Basic Types of temperature measuring devices (continued):
3. Thermoelectric
4. Thermojunctive
When 2 dissimilar metals at diff

Temperature Measurement
Thermoresistive temperature measuring devices
A change in temperature causes the electrical resistance of the material to change.
This resistance change is measured to infer temperature change.
2 Types:
1. RTDs (resistance temperat

Pressure Measurement
Absolute Pressure:
Gage Pressure:
How are absolute and gage pressure related?
Pressure Measurement
Bourdon Tubes
Pressure Transducers
Manometers
Bourdon Tube or C-type tubes are mechanical pressure gages (see picture in handout)
and a

Displacement Measurement
Potentiometers:
Based on the principle that a materials electrical resistance increases with length.
Displacement is inferred by measuring the change in resistance as a slider is displaced
along a potentiometer.
As displacement (x

MEGR 3171: Homework VI Displacement, velocity and acceleration
Submit your homework in a single folder in compliance with the filename requirements stated in
the first three homework exercises.
Fundamentals
1. What is the current definition of the meter a

Linear Regression and Correlation Analysis
A measured variable (measurand) is often a function of one or more independent variables that are
controlled during an experiment (well use 1 independent variable).
Regression analysis is used to find the relatio

Stress, Strain, and Strain Gages
Stress : When material is loaded with a force, the applied force per unit of crosssectional area is
Strain: The ratio of increase in length to original length
Hookes Law
Stress, Strain, and Strain Gages
Stress : When mater

Analysis of Data aka statistics
Why do we care about being competent in analyzing data as
engineers?
What is a population?
What is a sample?
Analysis of Data aka statistics
Measures of Central Tendency
M
M
M
When would you choose one over the other when r

MEGR3171L: Measurement and Instrumentation Project Laboratory
Required Materials
Students are required to provide the following and bring these to each laboratory exercise:
Bound (not spiral), lined, and numbered laboratory notebook cfw_See Student Guide

MEGR3171 Fall 2013 Displacement and Pressure Measurement Homework
1. Consider a linear potentiometer with a supply voltage of 4.00V. The output voltage reads
3.25V. The total length of the resistor is 8 cm. What is the displacement of the slider
along the

MEGR3171 Study Sheet for Test 1
What to Study
Strain Gages Measuring Strain
Know how to sketch a Wheatstone bridge circuit and how to derive the formula for
output voltage using basic circuit analysis
Know the relationship between stress, strain, and mo

1
MEGR 3171L Laboratory
Signal Processing I: Filter Circuits
Objective
The objectives of this project are twofold:
(1) Use the theoretical models developed in the Math Methods project to plan an
experiment to measure the frequency responses of a pair of R

1
MEGR 3171: Accelerometers
1.0 Objective
The first objective of this lab is to develop circuits using a MEMS accelerometer and
Labview to demonstrate the application of accelerometers to real engineering problems.
The second objective is to use a tri-axi

UNC CHARLOTTE
WILLIAM STATES LEE SCHOOL OF ENGINEERING
Version: Fall 2013
Overview
Electronic filters are devices used to select desired signals while rejecting unwanted
signals. For example, suppose that you connected a sensor to a mechanical system you

MEGR 3171L Laboratory: Aliasing
Objective
The objective of this project is to observe and evaluate the effect of aliasing on
measurements of periodic signals, both mechanical and electronic.
At the end of this exercise, the following aspects of aliasing s

Measuring Temperature
Introduction
Materials properties change dramatically in the presence of temperature changes. These
changes include expansion and contraction, phase change, change in strength and
hardness, change in chemical activity and other. Ther

Why are standard deviations important to us?
The normal distribution (Gaussian distribution) and the IQ score
example.
z scores give us a method of standardizing the infinite number of combinations of standard deviations and
means. We calculate z score by

MEGR 3171: Homework V Strain gages and circuits
Submit your homework in a single folder in compliance with the filename requirements stated in
the first three homework exercises.
Fundamentals
1. Sketch the current-voltage characteristics of a diode. (5 po