IEEE TRANSACTIONS ON EDUCATION, VOL. E-15, NO. 3, AUGUST 1972

Statewide Development of Sophomore-Level

Electrical Engineering Laboratories via

Project Colorado CO-TIE

WILLIAM LORD, MEMBER, IEEE, THOMAS W. WILLIAMS, AND LEE M. MAXWELL, MEMBER, IEEE

Abstract-Project Colorado CO-TIE was initiated in 1968 to COLORADO CO-TIEhelp college students in their transfer from two-year pre-engi- TELPACK UNES FORT COLLINS STERLING

neering programs to four-year degree-granting universities. The PRIVATELIS ---

main feature of CO-TIE is that videotapes of key sophomore-level courses (predominantly Network Analysis) are provided DENVERto the participating colleges. LETONExperience with CO-TIE has shown that colleges, in general, (AR JR COL

are inadequately equipped to provide undergraduate students JR. jj,

with the laboratory and computer facilities needed in a mod-ern, sophomore-level Network Analysis sequence. Recent uni- MCI

versity and college cooperation has been successful in the de- UNTA

sign and acquisition of both a sophomore-level Network Anal- |CO

^

ysis laboratory for each of the participants, and a statewide DURRINIDADAA(FORT LEWOSOLGE IAD STATE JR. COLLI

computer facility.WIlLTrfemmeU

INTRODUCTIONIn evaluating transcripts of college students entering engi-

neering programs at Colorado State University, it becameapparent that the traditional sophomore-level electric networkscourse sequence and the fluid mechanics course representedthe main obstacles to progress because these courses were

generally unavailable at junior colleges within the state.Primarily, with the transfer in mind, Colorado State Univer-

sity, with the cooperation of six colleges and the support ofthe National Science Foundation, in September 1968 launchedan imaginative new program entitled Project CO-TIE, an acro-

nym for Cooperation via Televised Instruction in Educationtion. 1,2,3 The program employs modern automated educa-tional techniques such as videotapes, electronic blackboard-by-wire, slow scan television and other low-data-rate trans-mission devices in a network reaching from Fort Collins to the

distant corners of the state of Colorado (see map).In its present form, the Electric Networks sequence has been

offered since the fall quarter of 1968 with the major objectiveof providing a unified, continuous and consistent theory oflinear, lumped parameter, time invariant physical systemsmodeling. It is intended that this sequence provide a soundbasis for junior and senior level courses such as control sys-

tems, network synthesis, vibration theory and others where a

Manuscript received August 30, 1971.W. Lord and L. M. Maxwell are with the Department of Electrical

Engineering, Colorado State University, Fort Collins, Colo.T. W. Williams is with the IBM Corporation, Endicott, N.Y.

knowledge of modeling techinques is of importance. In re-organizing the Electrical Engineering Department curriculumduring the past two years, significant emphasis has been placedon the following factors:

(1) Motivation of incoming freshman and sophomorestudents.(2) Use of the computer in the learning process.(3) Strengthening of formal coursework through well-

equipped and coordinated laboratory work.(4) Presentation of general concepts in a continuous,

unified and consistent manner even in introductory courses,thus providing a sound basis for more advanced courses inrelatively diverse areas of specialization.

Success has been achieved with regard to items (1) and (2)by initiating a heavily computer-oriented Engineering Princi-ples sequence in the freshman year and following recommenda-tions of the COSINE Committee in the sophomore-level Net-work Analysis sequence.4'5 As discussed under item (4), aunified approach to physical systems analysis has beenachieved by the adoption of the present EE 201, 202, 203Network Analysis sequence and the laboratory work was im-proved by the acquisition of an NSF grant in 1969.6From faculty visits to the off-campus locations, it soon

became obvious that the mere provision of videotapes to thecolleges was not providing the same educational environmentas experienced by the on-campus university students.In order to alleviate this final flaw in the system, strenuous

efforts have been made by the college and university faculty

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IEEE TRANSACTIONS ON EDUCATION, AUGUST 1972

involved in the program to obtain equivalent laboratory andcomputer facilities.An additional equipment grant has been obtained7 and the

final stages of a regional computer network are being planned.8The following sections describe in some detail the overalldesign of the laboratory and the equipment now available at allCO-TIE participating colleges.

CO-TIE COURSES, LABORATORIES ANDASSOCIATED COMPUTING ACTIVITY

Project Colorado CO-TIE is primarily concerned with thesophomore-level Network Analysis sequence which is a re-quired course for all engineering undergraduate students atCSU. The following is a brief description of the content ofthis course sequence:

EE 201 Network Analysis ILinear, lumped parameter, time invariant, physical net-works. Basic graph theory and matrix algebra applied tothe analysis of systems of linear algebraic components.Network theorems. Substitution techniques.

EE 202 Network Analysis IIState space concepts and the time domain analysis ofphysical systems containing energy storage components.Characteristics of first and second order systems. Sinus-oidal forcing functions.

EE 203 Network Analysis IIILaplace transform analysis of physical systems. Fourierseries. Two-port parameters. Mutually coupled networks.

Examples are chosen primarily from electrical and mechani-cal (translational and rotational) systems for analysis purposes.There are four laboratory exercises for each course. These

laboratories are designed so that a student can perform them inan hour and one half. Each laboratory assignment sheet has apreparation section which requires about one half hour ofwork before he arrives at the laboratory. At the end of thelaboratory exercise the student has either a hard copy of theresults or a table of results which completes his laboratoryexercise. The following is a list of the laboratory exerciseswhich were carried out by CSU students during the 1969-70academic year.The experiments have been designed to mesh very closely

with the coursework, and also to gradually expose students tostate-of-the-art measuring equipment.

EE 201 LaboratoriesLaboratory # 1. Measurement Schemes and Meter

OrientationPurpose: To give physical understanding of the element

defining equations for linear and non-linearelements.

Instruments: DC power supply, x-y recorder, varistor,resistor.

Laboratory #2. IntegrationPurpose: To give physical significance to integration, by

integrating different time functions.

Instruments: Function generator (sine, square, triangle),x-y recorder, analog computer.

Laboratory # 3. Element Defining Equation for a CapacitorPurpose: To graphically demonstrate the linear relation

between current and the derivative of the voltageof a capacitor. This laboratory also serves tointroduce the oscilloscope.

Instruments: Oscilloscope, function generator.Laboratory # 4. Norton and Thevenin Equivalent NetworksPurpose: 1) To determine the Thevenin and Norton Equiv-

alents of a given network by measurement.2) To observe the effect of meter orientation on

the equivalent networks.3) To verify the maximum power transfer

theorem.Instruments: Digital multimeters, DC power supply,

decade resistor.

EE 202 LaboratoriesLaboratory # 1. Determination of the Time Constant for a

First Order SystemPurpose: 1) To determine the time constant for an RC

network.2) To observe the effect of V, and R on the

time constant.Instruments: DC power supply, x-y recorder.

Laboratory # 2. The Series R-L NetworkPurpose: To determine the time constant for an RL

network.Instruments: Function generator, oscilloscope, decade

resistor, inductor.Laboratory #3. TheSeriesR-L-CNetworkPurpose: To determine the natural frequency, damping

ratio, rise time, and peak overshoot of an RLCnetwork by observing the state variables.

Instruments: Function generator, oscilloscope, decaderesistor, inductor, capacitor.

Laboratory # 4. Frequency Response of a Series R-L-CNetwork

Purpose: To determine the frequency response of a seriesRLC network, and to illustrate the concept ofresonance.

Instruments: Digital multimeters, oscilloscope, oscillator.

EE 203 LaboratoriesLaboratory # 1. Response ofa SeriesRCNetwork to

Various Input Voltage Wave FormsPurpose: This investigation illustrates the forced and nat-

ural response of an RC network to a suddenlyapplied sine wave, square wave, and triangularwave.

Instruments: Function generator, x-y recorder, decaderesistor, capacitor.

Laboratory #2. Simulation of a First Order System Usingthe Analog Computer

Purpose: To solve first order differential equations usingthe analog computer.

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LORD et at.: DEVELOPMENT OF ELECTRICAL ENGINEERING LABORATORIES

Instruments: Analog computer, DC power supply, x-yrecorder.

Laboratory # 3. Simulation ofa Second Order SystemUsing the Analog Computer

Purpose: To solve second order differential equationsusing the analog computer.

Instruments: Analog computer, DC power supply, x-yrecorder.

Laboratory # 4. Fourier SynthesisPurpose: To demonstrate Fourier Synthesis of a square

wave using four oscillators.Instruments: Four oscillators, oscilloscope.

During the 1971-72 academic year, many of these laboratoryexercises will be completed by the participating college stu-dents due to their acquisition of the necessary laboratoryequipment.In EE 201 and 202 the student writes his own programs to

solve first and second order differential equations and systemsof simultaneous equations. The numerical solutions to thefirst and second order differential equations are compared tothe laboratory results obtained in laboratory exercises 1, 2and 3 in EE 202.In the third course, EE 203, the student is introduced to

some of the standard network analysis programs such as ECAPand CIRCUS. The solutions obtained from these programs arealso compared to results obtained in the laboratory exercises1,2 and 3 in EE 203.With the expected development of a statewide computing

network in 1972 all participating CO-TIE college students willbe able to complete exactly the same assignments (whetherlaboratory or computer) as their on-campus counterparts.

LABORATORY EQUIPMENTThe Network Analysis laboratory at CSU has four equipped

stations6 which will accommodate a total of eight students atany one time. Each participating CO-TIE college will beequipped with one station. (See photograph.)The following is a list of the equipment in all laboratories:

1. MetersDarcy DM 330 Digital MultimeterEaling A294363 DC VoltmeterEaling A29-4397 MilliameterEaling A29-4413 AC VoltmeterEaling A29-4421 AC Milliameter

2. Power SuppliesEaling A28-1504 DC Regulated Power SupplyGeneral Radio Type 1310-A OscillatorHewlett Packard HP 202A Low Frequency FunctionGenerator

3. ComponentsGeneral Radio 1412-BC Decade CapacitorGeneral Radio 1434-G Decade ResistorUnited Transformer Company D1-2 Decade Inductor

4. Analog EquipmentPhilbrick/Nexus Model MP Operational ManifoldComponent Kit

5. RecordersHewlett Packard HP 120B OscilloscopeHewlett Packard HP 7035B x-y RecorderHewlett Packard HP 17108A Time Base

This equipment was chosen for the following reasons:

1. To expose the students to a wide range of measuringdevices and components from various manufacturers.

2. To allow students, whenever possible, to obtain hard-copy output from their laboratory exercises.

3. To provide students with reliable, state-of-the-artmeasuring equipment at reasonable cost. (The approximatetotal cost of each station was $5,000.)4. To introduce students to analog modeling of engineering

systems by use of a small, analog computer.5. To allow as high a degree of flexibility as possible such

that the colleges can use the equipment in many differentcourses.

CONCLUDING REMARKSIn our rapidly changing, technology-oriented society, it is

important that all students-regardless of their location-beprovided with equal opportunity. For college transfer studentsin engineering this does not merely mean the study of the samecoursework. Such students must also be provided with thesame facilities as their university counterparts if their transi-tion from pre-engineering to a degree program is to be trulysuccessful.

REFERENCES1. L. V. Baldwin, R. J. Churchill, W. Lord and L. M. Maxwell, "Univer-

sity, College and Industrial Cooperation in Higher Education,"Journal of the Institution ofElectrical Engineers, Vol. 16, pp. 13-18, January 1970.

2. L. M. Maxwell and W. Lord, "Effects of Educational Television onHigher Education in the State of Colorado," IEEE Trans. on Ed.,Vol. E-14, No. 1, pp. 1-6, February 1971.

3. W. Lord and L. M. Maxwell, "University Engineering EducationUsing Videotapes," Educational Research and Methods, Vol. 2,No. 4, pp. 25-28, June 1970.

4. Interim Report of the COSINE Committee of the Commission on

Engineering Education, "Some Specifications for a Computer Ori-ented First Course in Electrical Engineering," Journal ofEngineer-ing Education, Vol. 59, No. 5, pp. 391-394, January 1969.

5. W. Lord and L. M. Maxwell, "Modern Network Analysis and theComputer in Project Colorado CO-TIE," Proc. ofa Conference onComputers in the Undergraduate Curriculum, University of Iowa,pp. 3.47-3.56, June 1970.

6. NSF Instructional Scientific Equipment Grant No. GY-6846.7. NSF Instructional Scientific Equipment Grant No. GY-8197.8. NSF Office of Computing Activities Grant No. GJ-1086..

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