UNIVERSITY OF TORONTO
FACULTY OF APPLIED SCIENCE & ENGINEERING
First Year Program – Core 8 and TrackOne
FIRST YEAR PROGRAM
ENGINEERING PROBLEM SOLVING LABS
MAT188: Laboratory #12
Final Project
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Engineering Problem Solving Labs MAT188: Lab #12 Final Project
Faculty of Applied Science & Engineering 2 University of Toronto
FINAL PROJECT
Engineering Problem Solving Using MATLAB
In this series of labs you have gained a strong introduction to MATLAB and how it can be used to
understand situations and solve problems. You have been introduced to many fundamental functions
and commands and these have been summarized in the MATLAB Summary.
The purpose of this final project is to review the material presented in the past MATLAB labs and
exercises and use your engineering problem solving skills to better understand a real-life scenario.
Through this project you will work with on a real-life situation and create a script that will perform
simple analysis or computation so that you can draw conclusions from your analysis. Although the
suggested examples are chosen to be reasonably straightforward, they demonstrate how engineers
face real-world problems and how they use numeric and symbolic computation to help them reach
solutions.
For this final lab, select ONE PROJECT that is most interesting to you and work towards
finding a solution to the problem. Each project must have the following components:
1) Clearly Defined Problem Statement: Each project must have a clear problem statement,
which needs to be solved. This doesn’t mean that the problem is such that there is only one
“right” answer.
2) Real-World Scenario (Mathematical Model): Each project must be based on a real-world
situation, which includes a mathematical model that represents the situation using
fundamental scientific principles.
3) Design Parameter: At least one “design” or decision parameter must be included in the
problem, such that either the use of for loops and/or conditional statements (e.g., if-elseifelse-end)
are a required part of the analysis.
4) Deliverables: The submission for each project must include:
a) Script: You will need to create an m-file that generates all the plots and carries out your
analysis. It should include every calculation that you do and should include comments
throughout your script describing what variables and functions you are using and why.
b) Plots: You will need to create at least one two-dimensional plot for your project. Some
projects may require multiple plots or three-dimensional plots as well. Plots must be
properly labeled (axis and title) and include legend.
c) Concluding Statement: You will write a short paragraph that summarizes your analysis
and what your suggestion is for a “solution” to the problem.
d) A Description of your Engineering Problem Solving Process: You will also submit short
descriptions of how you have addressed each of the four key aspects of Pólya’s Problem
Solving Process that we have discussed in this course (see details below).
Preparation (Required to do before you come to the Lab session)
1. Read through this lab document and the suggested problems below.
2. Choose one of the six suggested problems.
Engineering Problem Solving Labs MAT188: Lab #12 Final Project
Faculty of Applied Science & Engineering 3 University of Toronto
George Pólya’s Problem Solving Process
Understanding the Problem
What is the unknown? (GOAL)
What relevant information is provided? (KNOWNS)
What is the condition? What fundamental principles are related? (FOUNDATION)
Draw a diagram. (VISUALIZATION)
Devising a Plan
Consider the unknown. What are the possible connections between the information
provided and the unknown.
Can the problem be restated in a more useful manner?
Do you know a related problem? Can you use its answer or its method?
Carrying Out the Plan
Check each step as you carry out the plan. Is it leading you in the right direction?
Looking Back
Can you check the result? How about the solution?
Is the answer complete? Have you solved the problem asked?
Submission for Final Project
You have ONE WEEK (7 DAYS) to complete this assignment, from the date of your lab. As part of this
lab, you must submit, your brief descriptions of:
1) Step 1: Understanding the Problem: What is your goal? What relevant information have you
been given? What are the fundamental scientific and/or mathematical concepts that you will
have to use to solve this problem? Include a simple hand-sketched diagram if it would be
helpful.
2) Step 2: Devising a Plan: Without writing or including in your submission ANY MATLAB
code, write out your step-by-step process that you plan on using in order to address this
problem. This might include:
a. The plot or plots you will generate to support your assessment and solution. What do
the x and y (or x, y, and z) axes represent?
b. The “algorithm”, or step-by-step process you will use in your MATLAB script. This
should be written in plain English, no need to use proper or exact MATLAB syntax. If
appropriate, include a graphical interpretation (flowchart) for your problem solving
process. Please also include any decisions/assumptions that you have made
3) Step 3: Carrying Out Your Plan: What did you do? How did you use MATLAB to solve the
problem? This should include:
a. The final version of your MATLAB script,
b. Any relevant plot or plots that you created to support your assessment, and
c. A brief description of ways in which you had to adapt your plan from that which you
originally envisioned in Step 2 above.
4) Step 4: Looking Back: How do you know that you have adequately addressed the problem?
How are you sure that you have achieved your goal? Is there anything you have learned
about the fundamental scientific and mathematical concepts and/or how to use MATLAB for
engineering problem solving? Make sure to include a short Concluding Statement that
summarizes your analysis and what your suggestion is for a “solution” to the problem.
Engineering Problem Solving Labs MAT188: Lab #12 Final Project
Faculty of Applied Science & Engineering 4 University of Toronto
SUBMISSION GUIDELINES
Please submit a single PDF file of maximum 4 pages of text, PLUS your MATLAB files (script,
plot, etc.) -- be clear and concise with your writing.
Your MATLAB script should run without any adjustments by the user (i.e., the TA). Make sure you
test and run your code before submission. Each student works must have an independent
submission.
Engineering Problem Solving Labs MAT188: Lab #12 Final Project
Faculty of Applied Science & Engineering 5 University of Toronto
Engineering Problem #1: Analysis of an Annotated ECG Signal
Background
Electrocardiography (ECG) is the process of recording the electrical activity of the heart over a
period of time using electrodes placed on a patient's body. ECG can help the physician in
primary diagnosis of different abnormalities in the electrical activity of the heart (arrhythmia). A
typical ECG tracing is a repeating cycle of three electrical entities: a P-wave, a QRS complex
and a T-wave (see Fig.1).
Fig 1. Representation of a normal heartbeat of the human1
.
Heart beat (rate) measurement is one of the simplest analyses of the heart activity. A heart rate
between 60 and 100 beats per minute is considered normal. A heart rate slower than 60 beats per
minute is said to be bradycardic and a rate faster than 100 beats per minute is said to
be tachycardia.
Problem Statement
Consider the ECG signals for three patients that have been posted on the course website. These
files, ecg1.mat, ecg2.mat, and ecg3.mat contain three columns: time (in seconds), signal voltage
(mV), and a marker code. This marker is an annotation of each point by an expert (physician).
In this annotation: 0 represents a point with no specific feature in the ECG signal, 1 represents
the peak of a P-wave, 2 annotates the Q point, 3 represents the peak of an R-wave, 4 represents a
S point, and finally 5 represents a T-wave peak.
Analyze these signals so that you can comment on the relative cardiac health of these patients.
You may want to focus your analysis on the measures of heartrate and the average PR-interval.
You can refer to http://www.ecglibrary.com/norm.php to help you in your assessment.
1
Source: https://upload.wikimedia.org/wikipedia/commons/thumb/9/9e/SinusRhythmLabels.svg/2000pxSinusRhythmLabels.svg.png,
Accessed November 16, 2017.
Engineering Problem Solving Labs MAT188: Lab #12 Final Project
Faculty of Applied Science & Engineering 6 University of Toronto
Engineering Problem #2: Electric Cars
Background
Electric cars, and plug-in hybrid-electric cars, are becoming more mainstream; the sales of cars
like Tesla’s Model 3, Nissan Leaf, Chevrolet Bolt, and other 2018 models have generally
increased over the past few years, and are projected to grow over the next decade as well.
This case study focuses on the economics of these vehicles as a mode of commuter
transportation for those who travel to/from the University of Toronto (return-trip).
Please select vehicles from the list here: https://insideevs.com/compare-plug-ins/
It may be necessary to perform additional research (other than the website listed above).
Problem Statement
It is possible to determine the before-tax cost, in CAD, for the base model (“lowest cost
model”) for each of the four vehicles you’ve selected.
It is possible to use the estimated range of each of these vehicles, as determined by the
2018 Fuel Consumption Guide (NRCAN.gc.ca), in litres/100km.
Use the fuel cost of $105.9 cents/litre for any fuel calculations, if necessary, and variable
electricity cost for a 24-hour period beginning 11/26/2018 at 12:00am and ending
11:59pm. Assume a 9am-6pm school day.
Ignore any maintenance and/or licensing costs; only consider the principal cost of the
vehicle and any fuel costs as appropriate.
The Questions
Determine the top three most economical vehicles for commuting to/from the Myhal Centre
Garage from 10 different points within a 50km radius of UofT. Account for fuel/electricity
costs, traffic at 9am and 6pm to the points you select, average maintenance costs, and so on.
Which vehicle is the most economical overall? Why?
Which vehicle is most economical at each 10km radius away from Toronto? What
impact, if any, does average traffic have on this? How would you use Matlab as a software tool to help maximize your fuel savings?
How does this compare to existing transit infrastructure (or walking or biking)? What are
other concerns to take into consideration?
Engineering Problem Solving Labs MAT188: Lab #12 Final Project
Faculty of Applied Science & Engineering 7 University of Toronto
Engineering Problem #3: Soil Temperature Modeling2
Background
In the construction of new urban systems, one of the
important considerations is the depth at which water pipes
must be buried in order to ensure they do not freeze. It is
possible to model this situation by considering how the
temperature within the soil at a depth relates to the
surface temperature,
, and the initial soil temperature,
,
over time(in seconds). It has been found that this can be
approximately represented by the equation:
Here, refers to a famous (and very useful) function in mathematics call the Gauss Error
Function, or simply the error function. It has the integral form shown above. The parameter
represents the thermal diffusivity of the soil.
Problem Statement
Prepare a report that summarizes how the soil temperature within Toronto would change with time
and depth over the course of a six-month period (December 1 – May 31). Most of the soil in
Toronto can be characterized as clay, and typically the initial soil temperature for all depths at the
start of December is = 14℃. You have been asked to consider the following specific cases:
a) Demonstrate how the temperature changes with time at a 0.75 m depth over the course of
the first 31 days (use increments of 1 day).
b) Show how the temperature changes with time (using 1 day increments) over the six-month
period for the range of depths of 0.05 m to 5 m.
c) Determine:
a. How deep the water lines need to be buried to ensure that the temperature does not
drop below 5℃.
b. How deep the water lines need to be buried in order for the surrounding soil
temperature to change by less than 1% of the initial soil temperature (i.e., 14℃).
2 Adapted from A. Gilat and V. Subramaniam, Numerical Methods for Engineers and Scientists, John Wiley & Sons,
2008, P7.27, pg. 306.
Surface Temperature
Initial Soil Temperature
Engineering Problem Solving Labs MAT188: Lab #12 Final Project
Faculty of Applied Science & Engineering 8 University of Toronto
Engineering Problem #4: Atmospheric Absorption of Electromagnetic Radiation
Background3
The way in which the electromagnetic radiation interacts
with the Earth’s atmosphere is an important aspect of many
engineering and scientific innovations and discoveries.
Satellite communications, radio astronomy, remote
sensing4
, solar energy, and understanding the process of
climate change all depend on our ability to describe how
electromagnetic waves, from radio to light, are transmitted
and absorbed by various layers of the Earth’s atmosphere.
For example, consider how UV, Visible, and Infrared
radiation (IR) are absorbed by the various constituents of
the Earth’s atmosphere (Figure 1). In particular, you can
see that carbon dioxide molecules have three regions of
absorption in the IR spectrum. They way in which the
molecule absorbs the energy contained in the IR photon, is
that it transfers this energy into kinetic energy through
vibrational motion5
. Much like a person pushing someone
on a swing, if the energy in the IR photon “pushes” the
oxygen and carbon atoms according to their natural rhythm then the movement of these atoms can
grow and be sustained. However, if the energy is associated with a different frequency of “pushing”
then the impulse is out of sync with the vibrational movement of the atoms and thus the energy of the
photon is not absorbed or converted into kinetic or another form of energy. This natural rhythm or
movement of CO2 depends on the atomic structure of that molecule.6
Specifically, if one looks carefully at the molecular structure of CO2 it is
possible to determine that the absorption peak occurs at = 4.3 μm is
due to the translational movement of the atoms along the axis of the
molecule. As a result, this allows us to approximate, or model the CO2
molecule as a three masses connected by two springs (Figure 2). Through
an analysis of the dynamics of this situation using the fundamental laws
of physics, one can derive the following relationships between the
masses, the spring constant , the frequency of vibration = 2, and
the amplitudes of translation or movement along the axis for each atom,
1
,2
, and 3
:
3 Downloaded from https://en.wikipedia.org/wiki/Absorption_band, used through Creative Commons license: CC BY-SA 3.0,
https://commons.wikimedia.org/w/index.php?curid=2623190
4 https://www.earthobservatory.nasa.gov/Features/RemoteSensing/remote_04.php
5 Recall that this energy is described by =
=, where f is the frequency in Hertz.
6 Taken from A. Gilat and V. Subramaniam, Numerical Methods for Engineers and Scientists, John Wiley & Sons, 2008, pg. 172.
Figure 1: Radiation Transmitted by the Atmosphere3
Figure 2: Spring/Mass Model of the
CO2 Molecule6
Engineering Problem Solving Labs MAT188: Lab #12 Final Project
Faculty of Applied Science & Engineering 9 University of Toronto
Problem Statement
Complete the spring/mass mathematical model of the CO2 molecule by using MATLAB to
determine the correct spring constant, so that the model properly predicts the absorption at
?? = 4.3 μm. Use the model to understand how the atoms in the CO2 molecules move when it
interacts with a photon that has a wavelength of = 4.3 μm. You should consider the problem
from the following perspective:
a) Observe that this can be considered to be an eigenvalue problem. Rewrite this system in
an eigenvalue format, i.e., is the eigenvalue vector rather than , since
in this problem represents the photon wavelength).
b) What are the eigenvalues and eigenvectors of this system? Use MATLAB to visualize
how they depend on the spring constant What do they mean and what conclusions can
you draw from them? Hint: Not all of the eigenvalues may be relevant to the actual
situation. For example, some may lead to complex results for the associated wavelength.
We suggest you only focus on the two eigenvalue – eigenvector pairs that lead to realvalued
results.
c) Knowing that measurements have shown that CO2 molecules demonstrate an absorption
at = 4.3 μm, what would be the correct value of the spring constant, for this model.
d) Briefly describe the limitations of this model. Why doesn’t it predict the clear absorption
around = 15 μm?
Engineering Problem Solving Labs MAT188: Lab #12 Final Project
Faculty of Applied Science & Engineering 10 University of Toronto
Engineering Problem #5: Saturn V Rocket Launch Analysis
Background
This problem involves using the ideal rocket equation to model the speed of the Saturn V rocket
throughout its takeoff and burn time. Rockets are propelled by the ejection of fuel from the aft of
the rocket, where Newton’s third law dictates that a forward force will act upon the rocket because
of this ejected mass. For a typical rocket, the fuel may make up approximately 90% of the total
mass of the rocket, thus it is important to consider the changing mass of the rocket as it accelerates.
Figure 1: Rocket schematic used for ideal rocket equation derivation1
.
To derive the ideal rocket equation, we note that the momentum of the rocket, will increase
due to its decreasing mass,increasing speed, and the conservation of the fuel ejected
in the opposite direction, an infinitesimal change in a rocket’s momentum can therefore be given
by:
is the mass of the rocket,is some small mass ejected from the rocket, and
is the
velocity of the ejected mass. We have ignored the very small term, (i.e., very small squared
equals very very very small, relative to the other larger terms). From Newton’s second law, we
know that the total impulse, ∑, must equal the change in momentum for our rocket, Δ.
Where for simplicity we will consider only the force of gravity acting at an angle of = 0, which
makes sense for the trajectory of a rocket . We therefore arrive at:.
Engineering Problem Solving Labs MAT188: Lab #12 Final Project
Faculty of Applied Science & Engineering 11 University of Toronto
Where we have made use of the fact that
. Integrating the above result gives us the
ideal rocket equation,
Where we have introduced the specific impulse , which is a common measure of the efficiency
of a rocket engine. The last equation gives the speed of the rocket in meters per second (m/s), it
is the one we will use throughout this analysis.
Problem Statement
You are asked to address three key issues with this situation by using the detailed information
below:
a) Use appropriate plots to visualize how the position, velocity and acceleration of the rocket
change with time.
b) Estimate the final velocity of the Saturn V rocket once all its fuel is used.
c) Determine if the rocket achieves the exit velocity required to leave the Earth’s orbit.
The Saturn V rocket consists of three stages. It is reasonable to assume that each stage fires
continuously, each stage lasts as long as its burn time, and the time taken between stages is
negligible. It is also known that the rocket doesn’t start leaving the launch tower until 6.5 s into
the Stage 1 burn time, i.e., ?(?? = 6.5 s) = 0. Some relevant parameters for each stage of the
Saturn V rocket are summarized in Table 1 below.
Table 1. Selected Saturn V rocket parameters2
Component Specific Impulse [s] Gross Mass [kg] Remaining Mass
[kg]
Burn Time [s]
1 263 2,290,000 130,000 165
2 421 496,200 40,100 360
3 421 123,000 13,500 500
Since fuel is consumed as the rocket fires, the mass of the rocket will decrease. Thus, we must
describe the variable as a function of time. It is reasonable to assume that the fuel is
consumed linearly, meaning
Engineering Problem Solving Labs MAT188: Lab #12 Final Project
Faculty of Applied Science & Engineering 12 University of Toronto
Engineering Problem #6: Robot Movement and Control
Background
In this project, we will be considering the movement (and control) of a robotic vehicle moving around
a 2D space. For instance, you can think of an autonomous vacuum cleaner moving around a room.
Here is the crux of the problem: in order to understand its working, and ultimately optimize its
performance, we would like to know a path that the robotic vehicle took during a certain interval of
time. However, any automated vehicle will only save its position (or share it with the central computer)
at regular time intervals. Of course, those intervals may be short, but we still only have access to
finitely many data points. From those points we want to reconstruct, as well as possible, the entire
motion of the vehicle7
.
Problem Statement
Consider the data saved in the posted robpos.mat data file. This file contains a matrix with 61 rows
and 3 columns, with positions of the robot measured every 1 second during an interval of 1 minute.
In each row, the first column represents the timestamp of the measurements (in seconds), the second
column represents the robot’s ??-coordinate in meters at the corresponding time, and the third column
represents its ??-coordinate in meters.
You are asked to:
a) Use this raw data to visualize a piecewise linear approximation of the position of this robot as it
moves through this 2D space, i.e., plot versus . Determine the values of the robot’s
velocity and acceleration from this raw data by considering this approach:
If the vehicle’s position at time is given by, an approximation of its speed at
time seconds, = 0,1, … ,59, is
2 = √
2,
and an approximation of its acceleration at time = 1,2, … ,59, is
1).
This is because the time increment is one second, i.e., ??? = 1s.
b) Use polynomial curve fitting techniques to create a smoother picture of how the robot has
moved through this 2D space and how its velocity and acceleration behave. Explain how this
approximate model compares to the original data. Remember that if you know how the velocity
and acceleration behave with respect to the and directions, then the total speed and
acceleration is given as the square root of the sum of the squares, i.e.,
c) Path control: You have now been asked to be part of a team that has to create a control
system that keeps the robot on a circular path. This path starts and ends at = (0,0),
has a diameter of 2.4 m, and takes 1 minute to complete one revolution. In order for your
team to know which signals to send to the motors that are controlling the movement in the
and directions, you have been asked to determine the velocity and acceleration values in
each direction that would be required for this kind of movement over one revolution.
7 As an interesting (and, perhaps, motivational) side note: problem of reconstruction of an object trajectory is a very
“real” and difficult problem in engineering and applied mathematics. This story was not invented purely for
educational purposes of learning Matlab. In fact, the author of this project, Melkior Ornik a former ECE PhD is
currently working on research in a particular setting of this problem, and the method outlined near the end of this
project is an actual strategy for reconstruction proposed by his colleagues in at least one publication.
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