Interdisciplinary Sophomore Design at Oakland Universitypeople.cst.cmich.edu/yelam1k/asee/proceedings/2011/data/78-177-1-dr.pdfand at least one other high-level programming language

Proceedings of the 2011 ASEE North Central & Illinois-Indiana Section Conference

Copyright © 2011, American Society for Engineering Education

Interdisciplinary Sophomore Design at Oakland University

Osamah Rawashdeh, Dave Schall, and Richard Haskell

School of Engineering and Computer Science

Oakland University, Rochester, MI 48309

Email: {rawashd2, schall2, haskell} @oakland.edu

Abstract A new core course, Design and Analysis of Electromechanical Systems, was taught for

the first time in the fall of 2006. This course is taken by all engineering students as part of a core

engineering course sequence in their sophomore year. Since then, this course has been offered

twice a year and has evolved into an interdisciplinary design experience, i.e., similar to a cap-

stone experience that students complete in their sophomore year before advancing to their major

specific coursework. This now unofficially known as the sophomore design course has become

very popular and produces exciting projects that are showcased every semester in a public event

together with our interdisciplinary senior design projects. Through these sophomore design

experiences, students gain great insights into all areas of engineering in addition to allowing

them to make a more informed decision on their major selection. This paper outlines the course

structure; topics covered, laboratory assignments, and descriptions of a set of selected projects

that resulted from this sophomore design course to illustrate the valuable experiences our

sophomore students are receiving.

Introduction All engineering students at Oakland University go through a common set of courses

before separating into their major related courses required by their respective programs of study.

The core courses cover various topics deemed necessary by ABET, our faculty, and our advisory

committees to provide a well rounded education to today’s engineering students. Another reason

behind the philosophy of the course was the need to increase student retention. All engineering

departments are involved in offering this set of courses.

The core course sequence is concluded with “EGR280 - Design and Analysis of

Electromechanical Systems.” It is offered twice a year (winter and fall semesters) and has an

average enrollment of 58 engineering and computer science students. The course was initially

developed and offered for the first time in the fall term of 2006 as an engineering statics and

dynamics course that uses computer technology to provide a more modern coverage of the topics

[1]. Traditional statics and dynamics courses are often “dry,” limiting the illustration of concepts

on pen and paper problems. EGR280 was developed to allow the use of sensors to measure

distance, speed, acceleration, etc. and processing these data in real-time by a microcontroller and

MATLAB to illustrate concepts in live demos and laboratory assignments.

After a few offerings of EGR280 and by allowing for more freedom on final project

ideas, we were surprised by the student’s abilities and enthusiasm. Students were putting great

pride and significant time and effort into completing their final projects. The results were

rivaling our senior design projects, which are similarly multidisciplinary in nature [2]. EGR280

is now unofficially known as the sophomore design course. The course instructors are making



the final project a significant focus of the course and teaching assistant, machine shop, and

electronic shop resources were provided to the course to raise the limits of what is possible.

The official course objectives have not changed, however. These are:

• Write C programs to interface a microcontroller to external devices and to download the

program to flash memory in a microcontroller using modern development tools.

• Solve statics problems involving particles and rigid bodies.

• Solve kinematic and kinetic dynamics problems involving particles and rigid bodies

using Newton's Second Law, Work and Energy, and Impulse and Momentum principles.

• Explain and illustrate the basic concepts of engineering ethics and apply them in practice.

• Work constructively in a multidisciplinary team to design, analyze, and describe an

electromechanical system subject to specific constraints.

This paper describes this course in detail. First, the course content is described, which

covers the first three course objectives above. Then the requirements and mechanics of the final

project are described followed by two sample final projects from resent semesters. A discussion

section describes course outcomes and some shortcomings in some detail. The ethics related

objective of the course is beyond the scope of this paper.

Course Content The course is divided into three parts. In the first five weeks, which are primarily

instructed by an Electrical and Computer Engineering (ECE) faculty member basic

microcontroller programming and interfaces are covered. In the next 6 weeks, a Mechanical

Engineering (ME) faculty member covers mechanical design topics. Throughout these first two

phases, discussed concepts are reinforced through weekly homework and lab assignments.

Finally, students work for 2 to 3 weeks on their final projects.

Electrical and Computer Engineering Part – The course starts out with an introduction to

microcontroller programming and interfacing. Students come in with a background in MATLAB

and at least one other high-level programming language in addition to having completed an intro

to ECE course, which covers basic analog and digital circuits. In EGR280, the Embedded C

language using the CodeWarrior complier is used to program an HCS12 microcontroller on a

Wytec Dragon12+ development board [5] shown in Fig. 1. The textbook used [5] provides a

library of pre-written functions for interfacing to various I/O devices using a learning-by-

example approach.



Fig. 1: Photo of Dragon12+ development board used in class showing the various peripherals

available.

Every topic in this portion is started with a high-level description followed by an in-class

code development and demonstration of concepts. This is achieved by using a projector to

display the complier, debugging, and programmer software tools on a screen in addition to an

overhead camera that shows the hardware running the developed code. All topics are reinforced

using homework assignments and weekly 3-hour lab sessions. Specifically the topics covered

are:

1. Introduction to electromechanical and embedded systems: The course starts out with

introductions and a video presentation of last year’s sophomore design projects in action.

2. General purpose I/O: Initializing port pins to a specific I/O mode and interfaces to

switches, pushbuttons, a hex-keypad, LEDs, four multiplexed 7-segemnt displays are

covered. All these peripheral I/O devices are provided on the Dragon12+ development

board.

3. LCDs: Students learn about ASCII characters and strings as well as common interfaces to

liquid Crystal displays (LCDs). Functions are used to control the 16x4 alphanumeric

displays provided on the development board.

4. Serial communication: The RS232 standard is covered and code is developed for

bidirectional serial Communication with a PC running HyperTerminal and MATLAB.

5. Data conversions: conversion of data between the binary format and ASCII string format

is discussed. A simple add-subtract calculator is implemented using the hex keypad and

the LCD provided on the development board.

6. Analog to digital conversion (ADC): Basics of analog to digital conversion are discussed

including resolution, quantization errors, and step sizes. Prewritten functions are used to

read the voltage of a linear potentiometer set up as a voltage divider on the development

board. In addition, a phototransistor is wired in class and code is written to implement a

simple light intensity meter.

7. Pulse width Modulation (PWM): The concept of PWM is reinforced and the selection and

driving of “toy” DC motors and hobby servos are discussed and demonstrated in class.

8. Interrupts: The concept of interrupts is covered and two examples are discussed in class

that makes use of the real-time-interrupt (RTI) peripheral on the HCS12. The first is a

traffic light controller that steps through a software encoded state machine. The second is



a Morse code generator, which flashes an LED and produces sounds using the onboard

buzzer driven using a square wave signal.

9. Conclusion: The ECE portion is concluded with a discussion of interfaces to various

sensors, such as a thermistor, and analog IR distance sensor, an analog 3-axis

accelerometer, a PWM ultrasonic distance sensor, and an analog resistive force sensor.

The class discussion is geared towards the use of such sensors and leads into a discussion

of ideas for final projects and how they could be realized.

Mechanical Engineering Part - The second six weeks of the semester covers some of the basic

concepts required for mechanical design. The topics are broken down into the two fundamental

areas of mechanics, namely statics and dynamics. The course is not intended to cover these

topics comprehensively; rather a survey of topics is presented that is broadly accessible to all

engineering majors. Mechanical Engineering students for example take a full statics and

dynamics course later in their studies. The following topics are covered:

1. Free-body Diagrams: The statics component starts by teaching students to draw free-

body diagrams for simple mechanical systems and introduces the concepts of reaction

forces, moments, and distributed forces.

2. Newton’s First Law: Students learn to balance force and moment equations. These

concepts are then used to solve problems involving reactions, trusses, machines and

frames.

3. Friction: Basic laws of friction are discussed and students are shown how to incorporate

friction into force and moment balance equations. As discussed below, examples from

previous projects are used to illustrate these concepts.

4. Kinematics: Projectile and relative motion are discussed. To stimulate student interest in

this topic, problems are derived in class from bicycle crash videos obtained on

YouTube™.

5. Kinetics: Topics including rigid-body dynamics (Newton’s Second Law), impulse-

momentum, and work-energy are presented.

6. Gears and motors: Because many of the student designs involve the use of gears and

motors, concepts such as torque-power curves, gear ratio, and servo selection are also

covered. Again, examples from previous courses are used as examples.

As indicated in the topics list above, previous projects are used to illustrate various concepts

whenever possible. In some cases, questions brought up by students concerning current

projects are addressed in class as well. For example, in the Fall of 2009, a group of students

created a final project entitled “Nerds dispensing Nerds”. In this project a proximity sensor

was employed to detect the presence of a hand. If a hand is present, a servo actuates and

dispenses a box of candy, as illustrated in Fig. 2a. In later classes, the project was used to

illustrate a number of concepts, namely the construction of simple free-body diagrams (Fig.

2b and c), reaction forces, friction, and torque. The students are also shown, based on the

mechanical design, how to pick a servo using the calculated torque and an appropriate safety

factor.

Proceedings of the 2011 ASEE North Central

Copyright © 2011

Fig. 2: a) Photo of the mechanical component of the

hidden from view moves the arm to the left which then drops the box of candy through the slot in

to a hand waiting below. b) Free

Integrated Laboratories The mechanics portion of the class also includes a series of laboratory exercises that build upon

the skills developed in the electrical and c

laboratory exercise, the microcontroller and a sensor are used to capture data. In one laboratory,

students measure the static coefficient of friction of an object using an inclined plane, an exercise

commonly conducted in elementary physics classes. The friction coefficient is given by the

equation µs=tan(θ), where θ is the angle of the inclined plane when the object begins sliding.

Rather than use a protractor to measure the angle, an accelerometer is mo

plane. The students must use the microcontroller to capture data output from the accelerometer.

This data is then converted into an angle and used to calculate the friction coefficient. In a

separate laboratory exercise, students use

data. Position, velocity, and acceleration are related through the definitions:

The accelerometer captures discrete numerical data which can be integrated numerically to

determine the velocity.

−)( 2 vtv

When integrated a second time the

collect their own acceleration data and write a MATLAB code to do the numerical integration to

obtain the velocity and position as a function of time. To test their code, the students are given a

data set created by the instructor and are asked to decode it by twice integrating to get the

relative position of the accelerometer as a function of time. When the y position is

function of the x position, the data spells out a secret message “Go OU”. Each of the laboratories

in the course builds upon the last. For example, the first mechanics lab utilizes the skills

developed during the microprocessor programming portion of the course to program the

ASEE North Central & Illinois-Indiana Section Conference


Photo of the mechanical component of the “Nerds Dispensing Nerds” project. A servo,


Free-body diagram of the bottom box of candy.

diagram of the actuator arm.

The mechanics portion of the class also includes a series of laboratory exercises that build upon

electrical and computer engineering portion of the course. In each



only conducted in elementary physics classes. The friction coefficient is given by the

is the angle of the inclined plane when the object begins sliding.

Rather than use a protractor to measure the angle, an accelerometer is mounted to the inclined



separate laboratory exercise, students use the accelerometer to capture and analyze acceleration

data. Position, velocity, and acceleration are related through the definitions:

v = dx/dt a = dv/dt


∫ ∑ ∆+≈=+

2

1

2

1

)()()( 121

1

t

t

t

t ii taadttatv

When integrated a second time the relative position as a function of time are obtained. Students


position as a function of time. To test their code, the students are given a


relative position of the accelerometer as a function of time. When the y position is


upon the last. For example, the first mechanics lab utilizes the skills


Conference

ispensing Nerds” project. A servo,


body diagram of the bottom box of candy. c) Free-body

The mechanics portion of the class also includes a series of laboratory exercises that build upon

portion of the course. In each



only conducted in elementary physics classes. The friction coefficient is given by the

is the angle of the inclined plane when the object begins sliding.

unted to the inclined



the accelerometer to capture and analyze acceleration


position as a function of time are obtained. Students


position as a function of time. To test their code, the students are given a


relative position of the accelerometer as a function of time. When the y position is plotted as a


upon the last. For example, the first mechanics lab utilizes the skills




microcontroller to read acceleration data. The second lab uses the code developed in the first lab

to capture acceleration data which is then analyzed using an external software package.

Final Projects About half-way through the term, students are asked to form multidisciplinary groups of 3 or 4

members. There are about 60 students every term of which about half are ME majors. An effort

is made that each team is equally balanced in terms of the majors represent. It should be noted

however that although the majority of students have declared a specific major when they take

this course, they all have taken the same engineering core courses and are equally prepared to

tackle the final project. In practice, however, we find that most students do have specific

strengths in their declared majors, which makes mixing majors in groups reasonable.

The assignment is simply to “design and implement a non-trivial system that interfaces at

least one sensor and one output device to a microcontroller.” A project planning form is

completed by each group that contains the specification of a group leader, some background and

goals, and some information on the propose project in form of high-level block diagrams with

some explanation. The two faculty members review the submitted planning form to insure that

all projects are acceptable and achievable. Written comments are provided to all groups and

personal meetings are conducted to discuss any issues. The main two issues are usually the lack

of detail or being too ambitious. During the meetings, the project plans are modified or refined

and to ensure that the group members have a good understanding and appreciation of their

project and the steps it will take to complete it.

Although students are encouraged and usually do start working on their projects well in

advance, only about 2 weeks of assignment-free time is allocated at the end of the semester for

students to focus on their final projects. Students have 24/7 access to a lab that uses a keypad for

entry control. TAs and instructors are to advise and help the students during regular lab hours

only.

Besides a final demonstration, students are required to prepare a poster as well as a full

written report. To assess group member participation and fair grading, anonymous peer

evaluations forms are completed by every student. Each group completes the semester by giving

a formal 10 minute poster presentation and demonstration to a group of faculty member

volunteers.

Sample Final Projects Over the past years, the resulting final projects have spanned a wide range of

applications. Variations of an autonomous canon (e.g., ping-pong ball or NERF launchers) have

been a favorite project theme. This probably is a direct result of explicitly covering projectile

motion and the interfacing of distance sensors (used for target distance detection) and servos (for

canon azimuth and elevation control) in lectures and labs. Another common project is the

implementation of small robots that respond to gesture control and/or utilize distance sensors for

obstacle avoidance or target tracking. This is a direct result of covering MEMS accelerometers,

distance sensors, and PWM DC motor control in the course.

Proceedings of the 2011 ASEE North Central

Copyright © 2011

There are about 14 sophomore

spanning various applications. For illustration proposes, two final projects are

detail. The first is an implementation of laser range finder that is mounted on an XY gimbal

using two servos. The second is remotely operated, gesture

Fig. 3: a) Photo showing wireless digital video camera and laser mounted in the multi

gimbal. b) Schematic diagram showing the geometry used to determine the targeting distance.

Project 1 - Laser Targeting System:

using a laser and a camera mounted

part to fulfill design requirements for an upcoming collegiate

The device is constructed using a wireless

multi-axis gimbal system (see Fig

two servos. Each servo was control

Java and Bluetooth to a Dragon 12+ Board.

video feed. The distance to the target was then determined via a real

using MATLAB. The MATLAB code determines the pixel location of the laser spot and uses

this information and the camera-laser separation distance to calculate the angle between the laser,

target, and camera (as illustrated in Fig

geometry, D = h / tan (θ). The students made use of an existing code [3]

The students wrote the control code for the servos and the interface for the Bluetooth device and

the Dragon 12+ board. In addition the student

determine the torque required for each servo to rotate the gimbal.

ASEE North Central & Illinois-Indiana Section Conference


There are about 14 sophomore design projects that result from this course every term,

For illustration proposes, two final projects are described


remotely operated, gesture-controlled paintball gun.

Photo showing wireless digital video camera and laser mounted in the multi

Schematic diagram showing the geometry used to determine the targeting distance.

Laser Targeting System: The purpose of this project was to identify

mounted on an unmanned aerial vehicle. The project was designed in

part to fulfill design requirements for an upcoming collegiate-level First Robotics competition.

The device is constructed using a wireless digital video camera and laser mounted coaxially in a

axis gimbal system (see Fig 3a). The camera and laser orientation were controlled using

controlled using a wireless Xbox controller broadcasting through

Java and Bluetooth to a Dragon 12+ Board. The target was located by visual inspection of the

video feed. The distance to the target was then determined via a real-time digital image analysis

MATLAB. The MATLAB code determines the pixel location of the laser spot and uses

laser separation distance to calculate the angle between the laser,

target, and camera (as illustrated in Fig 3b. The distance to the target fo

). The students made use of an existing code [3] for the image analysis.


In addition the students utilized equations of rotational motion to

determine the torque required for each servo to rotate the gimbal.

Conference

sult from this course every term,

described in more


controlled paintball gun.

Photo showing wireless digital video camera and laser mounted in the multi-axis

Schematic diagram showing the geometry used to determine the targeting distance.

to identify a target range

The project was designed in

l First Robotics competition.

and laser mounted coaxially in a

a). The camera and laser orientation were controlled using

led using a wireless Xbox controller broadcasting through

The target was located by visual inspection of the

time digital image analysis

MATLAB. The MATLAB code determines the pixel location of the laser spot and uses

laser separation distance to calculate the angle between the laser,

llows by simple

or the image analysis.


s utilized equations of rotational motion to



Fig. 4: Photos showing the Remote Turret with labeling of main components.

Project 2 – The Remote Turret: In this second sample project, students designed and

implemented a remotely operable paintball gun. As shown in Fig. 4, the paintball gun has a laser

pointer and webcam mounted on its barrel to allow remote viewing of the target area. The

HCS12 microcontroller drives a servo to operate the gun’s trigger as well as a second servo to

adjust the elevation of the barrel using a ball-bearing linkage rod. A DC motor is used to control

the azimuth angle. The turret is operated using a plastic toy gun that has and embedded

accelerometer for and a pushbutton for a trigger sensing. By watching the video feed from a

remote location, the user can control the azimuth and elevation of the paintball gun by gesturing

with the plastic toy gun and firing by pressing the push button. In this project, students gained an

understanding and experience in different aspects of designing an electromechanical system.

They had to solve the mechanical challenges involved in the 2-dimentional manipulation of the

gun and wrote software that samples several sensory inputs to control the action of the turret.

Discussion The sophomore design course has been a great success so far and has been perceived well

by the students, the engineering faculty, and visitors. The final projects are showcased in a public

event that includes our multi-disciplinary senior design competition event [2].

Based on student feedback and course evaluations, this course is perceived by the

majority of students as a “fun” and great learning experience. Two interesting phenomena have

been observed over the years this course has been offered. The first is that when the students are

presented with an overview and some videos of last term’s projects at the beginning of the

semester, many have a feeling of disbelief concerning their ability to build such systems. This

fear is gone by the end of the semester and is replaced with a feeling of accomplishment and

pride. We believe this is one of the most valuable outcomes of this course and has an impact on

student retention and performance in subsequent coursework, as they separate into their major

specific academic paths. The second is that we often hear during the semester from a student of

a specific major complaining about the necessity of learning about the other fields. Most often,

students with a declared ME major question the need for them to learn how to program and

interface I/O devices to a computer system. While we don’t succeed convincing every student



about this necessity, we are having good success in illustrating through this course the need for

today’s engineers to have skills that span multiple disciplines and possess multidisciplinary team

working abilities. The benefits of this course can be summarized as follows:

• Sophomore students gain hand-on experiences applying basic knowledge they learned

so far.

• Student gain a design experience on a project that allows them to learn about the

different areas of engineering.

• Students are given the opportunity to reconsider or confirm their declared choice of

major.

• Students gain written and oral communication skills through group discussions, final

reports, and poster presentations on the day of public demonstrations.

• The excitement and confidence students gain from completing final projects may help

retention.

• The final projects serve an important role for recruitment and publicity events.

As in all schools, curriculum development is an ongoing effort in our school. While the

sophomore deigns experience is generally well perceived and has be praised by recent ABET

reviewers, there are some critiques that arise in our committee meetings. The main critique is the

negative impact that this course has on our transfer student rates. It is feared that the uniqueness

of this course may cause some students to reconsider transferring to our university. In fact, we

have had several junior and senior transfer students in this course because they did not have an

equivalent course in their course of studies elsewhere. The second issue that is occasionally

discussed concerns the limit amount of credit hours available in our programs of studies, of

which this course takes four. While the course does introduce programming, computer control,

statics and dynamics, among other topics, they do not cover them in the depth a dedicated class

to any of these topics would do. The general consent is, however, that the benefits of this

sophomore design experience far outweigh the raised concerns.

Conclusion This paper described the sophomore design experience engineering students at Oakland

University complete in their second year, before going into the chosen major fields. The delivery

of ECE and ME topics is described as well as the mechanics of the final project. The two sample

projects provided illustrate the capabilities and achievements of the students at this level in their

educational careers. Faculty committees and external advisors are in agreement about the great

educational experience student are receiving in both a technical as well as in team-working

sense. Students get to apply knowledge they learn in class by developing an exciting system of

their choice. In student course evaluations and senior exit survey, the course is commonly

described as one of the best classes they had.

Acknowledgements The success of this course is in great part a result of the efforts and dedication of the

capable teaching assistants as well as the support of the staff in the Electronics Workshop and the

Machine Shop at the School of Engineering and Computer Science at Oakland University. Other

Faculty members that have taught and contributed also to the evolution of this course are: Dr.



Mike Latcha, Dr. Lorenzo Smith, Dr. Chris Kobus, and Dr. Beth Zou. The authors and students

owe them gratitude.

References [1] R. Haskell, M. Latcha, and O. Rawashdeh, "Do Microcontrollers Belong in a Sophomore Course on Statics and

Dynamics?," ASEE Annual Conference and Exhibit, June 2008.

[2] Latcha, M.A., Debnath, D., Elhajj, I., Gu, E., Haskell, R.E., "Melting-Pot Design at Oakland University,"

Proceedings of the National Senior Design Conference, Boulder, CO, June 2007.

[3] Danko, Todd, "Webcam Based DIY Laser Rangefinder." Webcam Based DIY Laser Rangefinder,” accessed 30

Nov. 2010, <https://sites.google.com/site/todddanko/home/webcam_laser_ranger?AuthEventSource=SSO>.

[4] Wytec Company, “HCS12/9S12: Dragon12-Plus-USB Trainer Board,” accessed 14 Ferbuary 2011, <

http://www.evbplus.com/9s12/9s12_hcs12.html>.

[5] Richard E. Haskell and Darrin M. Hanna, Learning By Example Using C - Programming the DRAGON12-Plus

Using CodeWarrior, LBE Books, Rochester, MI, 2008.

Documents

Interdisciplinary Sophomore Design at Oakland Universitypeople.cst.cmich.edu/yelam1k/asee/proceedings/2011/data/78-177-1-dr.pdfand at least one other high-level programming language