Hands-on Experiment-Based Pedagogical Approach in Engineering

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ANDS

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ON

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XPERIMENT

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ASED

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EDAGOGICAL

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PPROACH IN

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NGINEERING

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DUCATION

Dr. Hassan Bajwa

Department of Electrical Engineering

University of Bridgeport, Bridgeport, CT, USA hbajwa@bridgeport.edu

Mohammad Seddik

Department of Electrical Engineering

University of Bridgeport, Bridgeport, CT, USA hseddik@bridgeport.edu

A BSTRACT :

Teaching pedagogies are continuously evolving as technology transforms education practices by empowering students not only in the classrooms, but also in research laboratories. The task of reaching out to students from various backgrounds and capturing their imagination requires a fundamental and systematic approach [1]. In this paper we present hands-on experimental-based pedagogical efforts to encourage critical and creative thinking by allowing students to create relationships between mathematics and engineering.

Generally, engineering students are required to declare their major within the first year of college. Most engineering students come with certain interests and expectations about a particular professional career. Pedagogical methods that work with students from non- engineering disciplines vary for students within engineering fields. Narrative material without guided learning or overuse of learning aids effects students’ creativity [2].

Pedagogies of engagement such as discussion and debates are easily implemented in art and humanities courses, but are rarely implemented in engineering education courses.

Traditional teacher oriented lectures and blackboards are still commonly used in engineering classrooms. In this paper, we will present a few simple, hands-on lab experiments that can be used in interactive teaching modules. One challenge in teaching lab based courses is the acquisition of resources to develop labs and experiments. We will present experiments developed from kits and materials that can be acquired for minimal cost.

Development and integration of labs into engineering curricula also function as academic adjustment programs as well as a platform for student-faculty interaction which have proven to facilitate overall academic achievement and student retention [3, 4]. Studentteacher interaction is also necessary in developing a student-centered curriculum. The proposed labs help structure learning environment through interactive participation.

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I

NTRODUCTION

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With the restructuring of education pedagogies in many nontechnical courses, more emphasis is given to approaches such as classroom discussions, participation and student opinions. While such approaches have proven to be more effective, teacher centered approaches are still heavily used in engineering courses. Traditionally, engineering faculty use lectures and the blackboard approach while teaching. Engineers works with rules, laws and limitations, although out of the box thinking is always encouraged.

Engineering faculty are responsible to teach basic science and fundamentals of engineering such as, properties of material, components, rules and limitations.

Advancement in multimedia has given a new tool to the education community.

Engineering educators have also rapidly adopted multimedia for instructional purposes.

Along with the advantages and benefits however, is the excessive use of multimedia in education in general and engineering education in particular, which is a growing concern for the education community. In many engineering courses, traditional educational approaches are more effective. Solving mathematical equations on blackboard or paper is still the most effective way to learn concepts in engineering. Students as well as faculty should be reminded that learning is not limited to in-class instruction. It is not possible to absorb details by observing PowerPoint presentations, intuitive understanding need more interactive approaches.

Engineering curricula usually involve lab courses. These courses are designed to promote active and problem-based learning. Simulation can never replace experience of working with real objects. Lab courses usually have manuals to assist students. More often these manuals are step by step instruction on how to conduct an experiment, as the results students are unable to create a relationship between classroom instruction and lab courses. Instead of sparking creativity and helping students discover independently, such lab manuals hinder students’ creative thinking in many ways.

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ECOMMENDATION FOR INTERACTIVE ENGINEERING CLASS ROOM ENVIRONMENT

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In this paper we propose introducing real world engineering designs and technology in classrooms where students are learning the basics of science and engineering. We have developed some experiments as an example of such course.

Undergraduate engineering students usually lose their interest due to the demanding mathematics within the engineering courses. Many electrical engineering courses such as microwave and antenna design cannot be taught with mathematical derivation in details.

The faculty teaching such courses usually take the so called “Trust Me” approach, “trust me, you need to know this to be successful in your field”[1]. Student involvement in such courses can be increased through the introduction of real life application in instruction modules. We believe that students should be given an opportunity to practice what they learn and as they learn. They don’t have to wait for a semester or two to see how to use their education in practice.

I MPLEMENTATION OF E XPERIMENT -B ASED P EDAGOGICAL A PPROACH :

The engineering applications of electromagnetics require a deep understanding of

Maxwell's equations. Antenna design as an example is based on classical electromagnetic

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theory described by Maxwell's equations. Antenna characteristics such as gain, impedance, VSWR and reflection coefficient can be determined by Maxwell equation.

Here, we present a simple hands-on experiment that can serve as an interactive teaching module in microwave and antenna design courses.

In many antenna design and microwave courses, mathematical modeling and derivation is followed by designing of an antenna in simulation software. Usually students are unable to implement these designs during the semester. Here we present some experiments that can be integrated into graduate and undergraduate microwave and antenna design courses. Students should be implementing the design without taking a formal lab course.

We have designed several patch and conformal antennas from of-the-shelf material and components. Following mathematical derivation and simulation students should be encouraged to implement various designs and verifying the results. Antenna properties such as impendence and feed patterns depend on feed placement and are usually determined using Maxwell’s equations. Wave propagation in material can be understood with Maxwell equations. Maxwell equations enable us to understand how material properties effect engineering designs. High contact dielectric constant materials exhibits slow wave propagation and can be used to reduce antenna size. For the proposed learning modules students should be given different design and choice of materials to solve a design problem. In figure 1 we present a design of a dual band antenna that can be fabricated in interactive microwave classroom environment .

Figure 1: Design of dual band inverted F antenna in FEKO

We have fabricated and tested various antennas from material acquired from internet. The cost of material to build such antenna is shown in the table below. The cost includes supplies and material to build various antennas.

Material Cost approximately from Amazon.com

1 Copper foil and copper tapes of different thickness $ 30.00

2 Vernier Caliper $ 15.00

3 PTFE Sheet of different thickness

4 Cables and connectors

$ 12.00

$ 8.00

5 X-acto Knife kit $ 12.00

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X-act Knife

Total cost is around $ 80 in parts and supplies, not counting the wire, solders and measurements tools such as voltmeters available in any electrics lab. MOTS and RF modules to test antenna can be shared between students. Typically such modules cost approximate $80.00. Figure 3 below show the kit and figure 4 presents some antennas that are developed for a microwave course.

Copper Tape

Figure 3: Antenna Design Kit

Fabricated antennas

Copper sheets

Figure 4: Patch antenna and transmitters

RSSI stands for relative signal strength indicator and supplies a voltage output that is an indication of the received signal strength. 2.4GHz MOTS are used to test the antennas,

RSSI readings suggest that 2.4 GHz antenna outperform of the self dipole antennas: RSSI readings are given below:

RSSI reading from 2.4 GHz patch array are: 1.2 – 1.4.

RSSI reading from Off-the-shelf dipole antenna reading: 1.0 -1.1

RSSI reading from patch antenna are better than Off-the-shelf dipole antenna.

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UMMARY

Traditionally, engineering faculty use lectures and the blackboard approach while teaching. Development and integration of labs into engineering curricula is necessary to promote active and problem based learning. Mostly lab courses are offered as separate courses and students fail to create relationship between mathematics heavy class room lessons and lab courses. We have presented an example of hands-on lab experiments that could be integrated in microwave and antenna design courses and thus encourage interactive participation in traditional engineering courses.

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R EFERENCES :

1. Felder, R.M.W., Donald R.; Stice, James E. and Rugarcia, Armando, The Future

2. of Engineering Education: Part 2. Teaching Methods That Work.

Chem. Engr.

Education, , 2000. 34 (1): p. 26–39.

Krishna, P.C.M., G. Sebastien, and K. Gerhard. The impact of the nanoscale

3.

4. vision on the future of learning and teaching . 2006: SPIE.

Astin, A.W., What Matters in College: Four Critical Years Revisited . 1997:

Jossey-Bass

Terenzini, E.T.P.a.P.T., How college affects students: Findings and insights from twenty years of research . 1 ed. 1991: Jossey-Bass.

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