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V. Curriculum Structure: Rose-Hulman Institute
of Technology Sophomore Engineering Curriculum
At Rose-Hulman the engineering science
material usually covered in Dynamics, Thermodynamics I, Circuits
I and Fluid Mechanics has been repackaged into a new sequence of
courses called the Sophomore Engineering Curriculum (SEC) where
the concepts of conservation and accounting permeate the courses
and are used to tie the subjects together. This curriculum has its
pedagogical roots in a sophomore curriculum at Texas A&M University
[4] and there is at least one textbook that utilizes this methodology
[5]. This curriculum is required for all mechanical and electrical
engineering students.
A comparison between the old and new curriculum at
Rose-Hulman is illustrated in Figure 1. Parallel to the engineering
science course are three math courses Applied Math I (linear algebra
and some linear ordinary differential equations), Applied Math II
(statistics) and Applied Math II (systems of differential equations).
In Fig. 1, the dashed lines are intended to illustrate a weak coupling
between courses and a solid line is a strong coupling between courses.
One purpose of the Sophomore
Engineering Curriculum is to enhance the students' abilities in
solving problems in engineering analysis. We believe that the incoming
students have some misconceptions about the problem solving process
that need to be corrected before they can progress to the more difficult
problems that they will face later in their undergraduate careers.
These misconceptions include the ideas that, "solving problems
means finding a formula to evaluate," and "I can demonstrate
my cleverness by solving problems while showing as little of the
actual work as possible." To cause the students to change
some of their notions of problem solving, we require a far more
formalized and complete approach to problem solving than they have
yet experienced.
In the first course, ES201
Conservation and Accounting Principles, students are taught a problem
solving methodology and format that is used in all subsequent courses.
Next, students take three courses that build on the first course.
These courses are and “ES202 Fluid and Thermal Systems” “ES203 Electrical
Systems”, “ES204 Mechanical Systems”. In these courses more detailed
applications of the conservation principles within more specialized
problem areas are discussed as well as some of the additional topics
required to solve problems such as Kirchhoff’s voltage law and active
devices in “Electrical Systems”, properties in “Fluid and Thermal
Systems”, and kinematics in “Mechanical Systems.” Finally, the
material is brought back into a single course “ES205 Analysis and
Design of Engineering Systems” where multi-disciplinary problems
are tackled.
Brief Descriptions of the courses
ES201 Conservation and Accounting -- In ES201,
students are introduced to the elements of the conservation and
accounting framework that was describe above and to the problem-solving
approach based on the framework. In this class, students develop
models for systems by accounting for extensive properties that are
conserved such as mass, charge, linear momentum, angular momentum
and energy and also entropy. Initially, students work on problems
that focus their attention on one extensive problem, but as the
course progresses students may need to consider more than one extensive
property. For example, a problem may require conservation of mass,
conservation of energy, and conservation of linear momentum.
ES202 Fluid and Thermal Systems -- Students in ES202
apply the conservation and accounting framework to the specific
area of fluid and thermal systems. They both refine the framework
to focus on assumptions and extensive properties common to these
disciplines. They apply conservation of energy, conservation of
momentum, and entropy accounting to thermal and fluid systems. In
addition, they work with constituent properties related to fluid
and thermal systems, such as fluid and thermodynamic properties
of pure substances. Students work with both open and closed systems.
They consider special cases such as fluid statics, fluid dynamics,
mechanical energy balance and pipe flow, and lift and drag.
ES203 Electrical Systems -- Students in ES203
apply the conservation and accounting framework to the specific
area of electrical systems. They explore the assumptions necessary
to obtain Kirchoff's Laws from the conservation and accounting framework
[11] Starting with Kirchoff's Laws, students work with basic circuit
elements: sources, resistors, inductors, capacitors, and operational
amplifiers. They study traditional circuit topics such as voltage
and current dividers. They study transient behavior, especially
the cases of first and second order circuits. Finally, they student
sinusoidal steady-state behavior, AC circuits and power.
ES204 Mechanical Systems -- In
the Mechanical Systems course (ES204)
taken in the winter quarter, students learn the kinematics necessary
to apply the conservation principles to more difficult problems.
A traditional dynamics textbook is used in the course and the relationship
between how the principles are presented in the dynamics book and
how they were introduced the previous quarter is shown. Maple is
used extensively in the course and the dynamic simulation program
Working Model is used as a visualization tool [6]. The students
also perform three labs as a part of this course. The first lab
involves using Working Model, the second, angular momentum and the
third general plane motion.
In dynamics the primary kinetics principles
used to solve problems are usually presented as 1) direct application
of Newton’s Second Law, 2) work-energy methods, and 3) impulse-momentum
methods. In this curriculum these are presented as conservation
of linear and angular momentum (rate and finite time forms) and
conservation of energy (finite time form). A comparison of the
terminology is shown in Figure 2 that is given to the students at
the beginning of the course to help them relate the material in
the text to the material learned in the previous course.
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Principle
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ES201 Name
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Dynamics Name
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Comments
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Rate form for conservation of linear and angular momentum
for a closed system.
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Direct application of Newton’s Laws
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When to use:
-
want to find forces and/or accelerations
-
want to find velocities and/or distance traveled
(which can be found by separating variables and integrating
the basic kinematical relationships)
Other:
-
Be careful! These are vector equations.
- The book uses H0 for angular momentum instead
of L0.
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,
or if there are impulsive loads acting on the system
,
where Fi and Mi are the external impulsive
forces and moments acting on the system.
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Finite time form of conservation of linear and angular momentum
for a closed system.
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Impulse-momentum methods
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When to use:
- have an impact or impulsive forces
- the system consists of several objects
- given a force as a function of time
- want to find velocities, times, or forces (especially
impulsive forces)
Other:
-
Be careful! These are vector equations.
- The book uses H0 for angular momentum instead
of L0.
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Finite time form of conservation of energy for an adiabatic
closed system.
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Work-energy methods.
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When to use:
- have two locations in space
- given a force as a function of position
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want to find velocities, distances, or forces
(sometimes)
Other:
- This is a scalar equation
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Figure 2- A comparison between the nomenclature
used in Dynamics and the one used in Mechanical Systems
One advantage of this approach is that
as the kinematics is taught, it can immediately be applied to kinetics
problems thereby motivating the kinematics and reinforcing the kinetics.
For example, when normal and tangential coordinates are introduced
for particles, problems involving kinetics can be solved. These
problems may involve conservation of energy and/or direct application
of Newton’s Second Law, that is, the rate form of conservation of
linear momentum in our framework.
Another advantage of this approach
is that students are required to apply the principles “out-of-context”.
Typically in dynamics students know what principle to apply based
on the topic currently being discussed in class. With this arrangement
of the material, students need to decide which conservation principle
is most applicable. Similarly, after the kinematics associated
with fixed axis rotation is introduced, it is natural to extend
the range of problems to include those involving energy, as well
as linear and angular momentum for rigid bodies.
ES205 Analysis and Design of Engineering
Systems -- The material covered in the spring course, Analysis
and Design of Engineering Systems (ES205)
is similar to that covered in a traditional systems class. Equations
of motion are obtained for mechanical systems, electrical, electromechanical,
thermal, fluid, and hydraulic systems. For single degree of freedom
systems, topics of free response, step response and response due
to harmonic excitation and general periodic forcing, frequency response
plots (Bode plots), transfer functions, and Fourier Series are discussed.
The concepts of natural frequency and damping ratio are discussed
for mechanical as well as electrical and thermal problems. Associated
with this course is a three-hour lab devoted primarily to the writing
of product design specifications, although there are two more traditional
labs. One of the labs is focused on system identification for a
draining tank and the other involves modeling a DC motor/generator
system with a flexible shaft in Simulink.
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