Download Hands-On = Minds-On

Hands-On = Minds-On: Bringing Mechatronics to Life
Without Laboratory Time
Olakunle Harrison1
Abstract
Mechatronics provides an excellent opportunity to teach students problem solving skills in a multifaceted
engineering context. Teaching Mechatronics without laboratory time has required some innovation and a
rethinking of the way this nontraditional mechanical engineering course is taught. In this paper the author
describes various approaches used in teaching this interdisciplinary course. In the first half of the semester,
build-and-test exercises, referred to as Hands-On Assignments, are used to help students gain better
understanding of technical concepts covered during lecture. The assignments are a worthwhile substitute
for the traditional lab time. The ability of students to retain knowledge of concepts taught is considerably
improved when the opportunity exists to demonstrate what has been learned. The author shares some of his
experiences in developing and teaching this undergraduate mechanical engineering course.
Introduction
Early in the 1990’s Tuskegee University along with several other universities in the Synthesis Coalition,
sponsored by the National Science Foundation, embarked on an engineering curriculum improvement effort
that included the introduction of Mechatronics into the respective universities’ programs [1]. It was the
resulting Mechatronics course and laboratory that the author inherited. Improvements and adaptations, to
be discussed later, have since been made to help students get the most out of the course.
The Mechatronics course at Tuskegee University combines a treatment of basic electronic components with
software control of mechanical devices and systems. For the students, this course is unlike any of the
traditional mechanical engineering courses in that it provides many opportunities to learn about electronic
and mechanical components and how they can be integrated with software to produce better, cost effective
solutions. Because of the nature of the subject and the volume of information to be exchanged, it is crucial to
memory retention that students be exposed to laboratory exercises that reflect realistic engineering practice.
The demands on instructor and graduate teaching assistant time is considerably greater than in other
courses because of the numerous interactions required to help students complete their assignments and
grasp the material taught. But, the rewards for both instructor and student are significant.
The goals for student learning in this three-hour credit course are as follows:

Apply knowledge of passive and active electronic components
1
Assistant Professor, Mechanical Engineering, Tuskegee University, Tuskegee, AL 36088
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
Understand basic concepts of digital electronics

Control mechanical systems by interfacing sensors and software

Become more proficient in programming as it applies to mechanical system control

Understand fundamentals of data acquisition
The undergraduate Mechatronics course at Tuskegee is a required senior level course currently taught only
by mechanical engineering (ME) faculty. However, a multidisciplinary flavor is obtained due to the fact that
students in electrical and aerospace engineering (EE and AE) departments also take the course as a
technical elective. Teams are formed by pairing EE students with other majors, thus providing a taste of the
reality that obtains in industry. The textbook used for the course is “Introduction to Mechatronics and
Measurement Systems” by M. Histand and D. Alciatore.
The grading scheme used for the course is as follows:

Homework
15%

Hands-on Assignments
25%

Projects
15%

Exams I, II, and III
10, 10, 10%

Final Exam
15%
Innovative Methods Used in the Course
The course is taught in the Mechatronics laboratory which allows for regular classroom seating with
students surrounded by workstations and project hardware. One of the author’s strategies to help stimulate
and maintain student interest is the adoption of a seamless transition between the traditional lecture format
and laboratory exercises and demonstrations. Thus, during a class period, students may be introduced to a
theory or concept and then immediately get to see or perform a demonstration of its application. This
approach engages the students considerably with the result that their minds stay on task more than in most
other courses. Other methods used in the course are discussed hereafter.
Hands-on Assignments
Perhaps the most striking observation about student preparedness for this course is that many initially find
it challenging to translate circuit diagrams into actual working circuits. Usually, the ME students are filled
with trepidation that their brief encounter with electrical circuits and machines in the sophomore or junior
year will not serve them well in Mechatronics. Their fears are allayed by spending the first few weeks of the
semester in review of fundamentals. Build-and-test exercises, referred to as Hands-on Assignments, are
utilized to help students gain a more complete understanding of the engineering principles covered in class
using actual functional devices. This groundwork is crucial to understanding what lies ahead in
mechatronics. These hands-on assignments differ from those of a traditional laboratory because of their
brevity as well as the method by which the students go about completing the assignments. Unlike
traditional laboratory exercises, students are only given a brief description of what is required. They then
turn to their class notes to find answers to various problems pertaining to necessary circuit diagrams,
calculations, hook-up methods, and other tasks associated with the exercise. Using this approach
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significantly enhances their problem solving skills because they are mentally drawn into the exercise and
have to think their way through- hands-on as well as minds-on. Typical hands-on assignments are as
follows:
1. Constructing Basic Circuits (Resistive circuits with incandescent lamp and switches)
2. Employing Light Emitting Diodes in Circuits (Use capacitor along with a SPDT switch to drive LED)
3. Using the Zener Diode in a Circuit (Record Zener voltage while varying source voltage)
4. Using Bipolar Junction Transistor to switch a DC motor on and off
5. Using Relays in Circuits (Use BJT to switch relay and, in turn, switch DC motor on and off)
6. Controlling a DC Motor Using the MOSFET (Add LED’s to indicate on/off status)
7. Using BJT’s with MOSFET’s for Motor Control
8. Sensing Object Presence Using an Opto-isolator
9. Determining Motor RPM Using Opto-isolator
10. Using the Operational Amplifier for Amplification
11. Computer Interfacing with Digital Input and Output (Use trainer board for I/O)
These hands-on assignments are a worthwhile substitute for the traditional lab time and go a long way in
reinforcing lecture material. Most of the hands-on assignments are single purposed and can be completed
during the second half of a one-hour class period. In the second half of the semester, the assignments
require more time and greater effort and are treated as mini projects. The goals for all assignments center
on providing students with realistic experiences that will increase their confidence in multidisciplinary
problem solving.
Mechatronics Kits for Student Use
Students in the class are paired up and assigned a portable, take-home mechatronics kit which comprises a
commercially available training board complete with basic electronic components and a multi-meter. The
kit, or “lab-in-a-box”, effectively extends the time that students interact with the course material, teaching
assistant, and instructor. Thus, the kit compensates for the lack of lab time. The kit includes a trainer
board that consists of a solderless breadboard, a six-step voltage supply, various switches, 8 LED’s, a sevensegment LED, a potentiometers. The trainer board is placed in a padded aluminum brief case along with a
multimeter and a variety of electronics components including transistors, diodes, dc motor, and stepper
motor. Students are given additional components as new topics are covered in class.
Another benefit derived from giving students these kits is that they have the opportunity to conduct
experiments beyond those that were assigned in class. We have had students use the kit and their newly
found knowledge in Mechatronics to do proof-of-concept presentations in other engineering courses.
Although many electrical engineering students have been required to own their own kits for years, it
remains a significant area of opportunity for engaging ME students taking Mechatronics and introducing
much-needed excitement and a sense of purpose to the discipline.
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Short-term Projects
The lack of adequate laboratory time has also required innovative thinking in assigned projects. Short-term
design projects are assigned to help the students get relatively quick feedback both with regard to their
knowledge and their sense of accomplishment. Although the more involved design projects have their place
and do yield significant delight when the students finally accomplish their goals, the author finds that the
typical ME student is usually in new territory when it comes to the electronics aspects of mechatronic
projects. Consequently, an extended design project that requires significant mechanical construction may
detract from the learning objectives and is not considered necessary to meet those objectives. Three typical
projects assigned to students are as follows:

Control of an Automatic Stapler

Temperature Data Acquisition with LED Readout

Model Factory Conveyor System Control
In order to save precious time, design projects involve ready-made systems that students only have to outfit
with sensors and switches in order to achieve the desired functions. One such project involves an automatic
stapler such as used inside photocopiers. Students are required to design a mechatronic system assuming
that the stapler is operating within a copier as originally designed. Thus, students must address issues such
as the maximum number of pages to be stapled, an out-of-staple or cartridge-not-present situation,
initialization of the stapler ram to its top-dead-center position, time delays preceding stapling, and the
sensing of paper jams in the stapler area. Opto-isolator sensors and micro-switches are used to indicate
machine status. Students get to interface the stapler with a computer and are responsible for the entire
circuitry. A “C” program is written to control the operation of the stapler subject to the various conditions
present.
The temperature data acquisition project involves circuit construction and the necessary programming to
monitor temperature variations in the laboratory. An analog-to-digital converter is used along with a PIC
microcontroller (PIC 16F84) from MicrochipTM to perform the task. A two-digit seven-segment LED is
thrown into the mix for temperature display. Each team’s grade on the project depends on how much of the
project is completed, with an opportunity to score more than 100% for a perfect project. By far, most
students strive for the perfect score.
A third project involves the use of a programmable logic controller to drive a model factory conveyor belt
moving a work piece from one station to another, Fig. 1. Adequate delays are necessary for the task at each
station to be completed. Pneumatic cylinders are used to simulate work performed on the work piece.
Rejected workpieces are pushed onto a secondary conveyor belt that must be activated for a given length of
time. Students are required to write the program to control this system.
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Red Light
Reject Line
Switch
Workpiece
Sensor 1
Sensor 2
Work Station 2
Pneumatic Ram
Work Station 1
Fig. 1: Schematic of a Model Factory Conveyor System used in PLC project.
Students’ problem-solving skills are enhanced considerably with these short-term projects. They receive
feedback on their performance rather quickly, as the project results are self-evident. Their troubleshooting
skills are further enhanced by the multitude of problems that crop up in their efforts to complete the
projects.
The problems that students encounter span selecting components, calculations, circuit
construction, and programming, [2].
These relatively short-term (1-week) projects communicate the essentials of mechatronics, i.e. thinking of the
system as an integrated whole with an awareness of the essential principles of operation of electronic
components, and the tying of mechanical events to software programming using sensors for a more costeffective and robust system.
The additional overhead associated with designing, building, and testing mechanical devices – tasks
typically encountered in the Capstone Design course, do not present a problem in the approach described
here. Yet, students still acquire significant skill sets that will be useful to them immediately upon
graduating. It is expected that, after this course, the student will be better versed in the conceptual design
phase of product development, be more innovative in providing solutions to technical problems in
contemporary devices and products, and be better prepared for job functions such as designing test
apparatus to meet some particular need.
Facilitating Self-directed Learning
Of all the learning people acquire in their lifetime, none is more valuable than learning how to learn on their
own [3]. As educators, one of our main goals for our students is that they embrace life-long learning and
develop the ability to formulate and solve problems.
Mechatronics offers an excellent opportunity to
reinforce practices and attitudes that will enable students to explore solutions when confronted with
multidisciplinary-type problems. In teaching this course, students are nurtured and encouraged to become
self-directed in solving problems. A variety of vehicles are used in this nurturing process.
Various elements of the problem-based learning teaching method are used in this course. For example,
when an electronic device, say a transistor, is introduced and discussed in class, students receive copies of
the manufacturer’s data sheet for the component. Using a discussion style format, students identify the
relevant parameters, their meanings, maximum or minimum values and how these figure into the overall
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design of the mechatronic system. Consequently, students are placed in the position of the practicing
engineer in industry, a situation which enhances their problem-solving skills.
Another approach that encourages self-reliance is the requirement that the student give a verbal account of
the effort expended in correcting problems associated with non-working systems. Frequently, we find that
students fail to employ fundamental troubleshooting strategies in trying to get their systems to function.
This requirement of accountability helps students work their way through problems.
Of all the gifts that schooling can bestow upon students, nothing is more important than teaching them how
to learn on their own [3]. When the teaching takes place in a familiar context, such as with smart devices
and automated systems, students are empowered to learn on their own and reap benefits far beyond those
available in traditional class structures. By keeping doing and thinking together [4], the approach described
in this paper helps students learn about learning.
Results
The approach to teaching a 3-credit mechatronics course without the benefit of laboratory time described
here promotes greater student participation in the learning process, attentiveness, and the development of
more independent, critical thinking skills. The hands-on exercises help in reinforcing knowledge of the
essentials of mechatronic systems, as well as to quickly point out weaknesses in student preparedness.
Short-term projects help students get relatively quick feedback both with regard to their knowledge of the
subject and their sense of accomplishment.
Student performance on assignments and exams has been, on average, better than in other courses that the
author teaches. About 30% more students get A’s and B’s in Mechatronics. Although it is difficult to
compare this course to other ME courses, a measure of positive results can be found in heightened student
interest. Most students complete all assignments and projects, with some needing more than the allotted
time.
Conclusion
The author’s goals for the hands-on assignments center around providing students with problem solving and
engineering practice experiences that will allow each student to gain more confidence in his/her ability to
solve multi-faceted problems. Furthermore, the teaching approach described here encourages self-reliance
in figuring out what pieces of information are needed to solve problems and how to find that information. It
is important that students be taught problem-solving skills that can be put to use rather quickly upon
entering the workforce. One student talked about getting a job with a major corporation doing work
associated with PLC control, a subject with which he had just become familiar during the same semester.
Overall, the author’s experience with this course has been very positive. Because of the realism of the
exercises in the course and the way students are engaged, they get a true sense of accomplishment as well as
the ability to make meaningful contributions to product development activities related to mechatronic
systems.
References
1. http://www.synthesis.org/
2. Hodge, H., H.S. Hinton, and M. Lightner, “Virtual Circuit Laboratory,” Journal of Engineering Education,
vol. 90, no. 4, 2001, p.507.
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3. Friedman, Myles, (2000), Ensuring Student Success: A Handbook of Evidence-Based Strategies, The
Institute for Evidence-Based Decision-Making in Education, Inc., Columbia, South Carolina, p.155.
4. Lindeman, Eduard C., 1961, The Meaning of Adult Education, The Oklahoma Research Center for
Continuing Professional and Higher Education, Norman, Oklahoma, pp.6-7.
.
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Olakunle Harrison
Olakunle Harrison is an assistant professor of Mechanical Engineering at Tuskegee University. He joined Tuskegee in 1997 and has
since taught courses in mechanics, automotive systems, machine design, capstone design, mechatronics, and design for manufacturing.
He received his bachelor’s degree in Mechanical Engineering from the University of Tennessee, Knoxville, in 1986 and went on to
receive the master’s and Ph.D. degrees from the same university in 1989 and 1995, respectively. He currently serves as the ASME and
SAE faculty advisor at Tuskegee University and is developing an Automotive Systems focused research effort at Tuskegee University.
Dr. Harrison has also directed summer academic program for pre-college and entering engineering freshmen. His research interests are
in automotive systems, mechatronics, engineering design, product development, and design for manufacturing and assembly. He is a
registered professional engineer in the state of Alabama.