Download MATLAB Problems – Lab #10

Sacramento State
Department of Electrical & Electronic Engineering
ENGR 1A-04 Fundamentals of Engineering
Laboratory #9 and #10 – Introduction to MATLAB and MATLAB Problem Solving
MATLAB, from The Mathworks, Inc, is another one of those industry standard software
packages that is used for analysis and design in virtually all of the engineering fields. These two
laboratory exercises are designed to introduce you to MATLAB and leave you with some
understanding of its valuable capabilities for problem solving. Your lecture (refer to the
PowerPoint presentation on the course web page) and associated handout material have provided
you with some introduction to the software. The Tutorial Lessons provided with this lab
assignment will help you develop more “hands-on” familiarity with it. The MATLAB problems
provided from exercises throughout the course will help you appreciate its value.
Procedure for Introduction to MATLAB – Lab #9
1. Open the MATLAB program on any ECS networked workstation.
2. Read the1.6 Basics of MATLAB section of the Tutorial provided, and get familiar with
the windows that appear on your startup screen. Ask questions of the instructor if you are
not clear about the general operation of the software.
3. Begin the section 2 Tutorial Lessons.
4. Do Lesson 1. At the end of the lesson, do exercises 1-3. (Skip exercise 4.) Copy the
Command Window output for each exercise and paste it into a MS Word document to
save for your lab report. Check your answer to each exercise with the Answers to
Exercises section at the end of this lesson.
5. Do Lesson 2. Do exercises 1-4 at the end of this lesson. (Skip exercise 5.) Copy the
Command Window output for each exercise and paste it into your Word document.
Check your answers.
6. Do Lesson 3. Do exercises 1,2,4, and 6 at the end of this lesson. Copy the Command
Window output to your Word document. Check your answers.
7. Do Lesson 4. Do exercises 1-5 at the end of this lesson. Copy the Command Window
output to your Word document. Check your answers.
MATLAB Problems – Lab #10
You are now ready to tackle some useful problems encountered in this course using MATLAB.
For each problem, copy the Command Window output to a MS Word file for your report. In
problem 4, also copy your m-file program.
Do one of the first three problems (your choice) plus problems 4 and 5.
1. Use MATLAB to calculate the Tower Height above Sea Level of the Guy West Bridge
East Tower. Use the data provided in the handout on the course web page. (NB –
MATLAB trigonometric functions (sin and cos) assume that the angles are given in
radians. There are  radians in 180 º.)
2. Refer to the data in the handout “NFL Football Weight Calculation”. Use MATLAB to
calculate and confirm the mass in kilograms of the Air-filled and He-filled NFL footballs.
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3. Refer to the handout “Winning at the Drag Strip and Hill Climb with VEX Electric
Motors”. Assume your vehicle weighs 2.5 kg. Choose the best combination of wheel
radius, gear ratio, and motor stall torque for the Drag Race Challenge. Use MATLAB to
calculate how far your vehicle will go (x), if we let it race for exactly 5 s?
4. Assume all the vehicle design parameters in the next-to-last paragraph of the “At the Hill
Climb” section of the above handout, except for the stall torque (s). Solve the equation
in that paragraph to determine how much stall torque (s) you will need from the motors
of the vehicle to climb at an incline angle (). Write an m-file program that will use
MATLAB to plot climb angle () against stall torque (s) for angles ranging from 20 to
60 degrees in increments of 5 degrees. (Remember, MATLAB needs angles in radians
for the calculation of trigonometric functions.)
5. Refer to page 3 of the handout “Electric Circuits”. Use MATLAB to solve the matrix
equation for the three currents in the multi-loop circuit. [Hint: A matrix equation can be
solved most easily using the coefficient matrix inverse. Use MATLAB Help to find out
about the matrix inverse and how to solve a matrix equation with it. Then use MATLAB
to solve the equation and confirm the values for the currents presented in the handout.]
Each student should submit a report concerning these two laboratory exercises. Reports
are due by Monday, December 18, 2006.
The report should provide the following information:
1. Objectives: In your own words, describe the objectives of these laboratory exercises.
2. Results and Discussion: Present your results from the exercises in Lessons 1-4. Did all
of your results agree with the answers given in the Tutorial? If any did not, can you
suggest why? Present your results of the MATLAB Problems. Do those results agree
with what you expected?
3. Conclusions: What have you learned from your experience with MATLAB software?
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