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Send the Lab Home

Why today's engineering students need a portable lab bench at their fingertips.

By Kathleen Meehan


Develop the lab and students will come, but they may not get into the class. However, if you move the lab out of the classroom with experiments designed so that students can work on them from any location, and if you offer online tutorials to assist students as they work, then there is no limit to the number of students who can enroll in the lab.

This basic premise guides the "Lab-in-a-Box" model that Virginia Tech developed a few years ago -- out of necessity. Virginia Tech's Bradley Department of Electrical and Computer Engineering (ECE) currently has about 750 undergraduate students enrolled in the circuits and electronics laboratory courses per semester and just 32 seats between the two circuits and electronics laboratory classrooms. With 2-3 hours of lab per week, that's almost 50 lab sections to schedule and staff. The task proved impossible - there weren't enough hours in a week, let alone a budget for all of these labs.

Instead, we took the lab out of the classroom. Thanks to recent innovations, our students can use their portable lab bench - an analog design kit with a personal computer - at home. This innovation allows many more engineering students to experience the thrill of hands-on learning when conducting their lab assignments or when experimenting with their own circuit designs as curiosity strikes. This flexibility is especially important today.

The kit includes a multimeter, USB-powered oscilloscope, powered circuit trainer with an attached breadboard, and electronic components. With the support of corporate leaders such as Analog Devices Inc., the cost of basic analog design kits ($99-$199) is about the same as a textbook. And, the kit keeps getting better as these companies improve the equipment. Plus, some of the companies provide engineering expertise and free online educational material for students and faculty.

These are challenging but exciting times for engineering. A recent cover story in Prism, the magazine of the American Society for Engineering Education, reported on how colleges are bringing hands-on learning into the curriculum. While the initiatives vary in scope, all are designed to keep students revved up on engineering. Our students love Lab-in-a-Box. Students say that they develop self-confidence in their engineering skills and a deeper understanding of the concepts in circuits and electronics when they applied the concepts in the circuits that they construct and then compare the actual measurements with their calculations. The process is much more satisfying when they build a circuit with real components instead of the "symbolic" parts used in circuit simulation programs.

Students crave the convenience associated with Lab-in-a-Box because they can take the analog design kit home. But, the students aren't totally on their own. Thanks to a grant from the NSF, we've put Lab-in-a-Box online with multimedia learning materials including short lectures and more than 60 tutorials (www.lab-in-a-box.net).

Virginia Tech is also developing ways, using popular online voice-and-video programs like Skype, to have professors "look over the shoulder" of their students as they carry out experiments, take measurements, and analyze the data. This type of instruction has enabled us to offer some of our circuits laboratory classes entirely online.

In addition, we have worked with companies such as MathWorks and Digilent to make sure that students can close the engineering design cycle. Students can export data from the oscilloscope and overlay measurements on top of the results of their calculations. This visual helps guide them as they identify reasons why their circuit designs are not ideal and helps students gain an intuitive understanding of engineering practices.

The online lab solves some of the thorniest problems in engineering education nationwide. Space for laboratories is a big issue for almost all colleges, yet there is a demand to educate more engineers. And, who can afford to build and outfit new laboratories? Our kit - and others like it - perform just like the benchtop measurement equipment that have been used in our circuits laboratory classrooms, which cost upwards of $10,000 for a two-person lab bench. Imagine the possibilities for community college programs that have no lab classroom at all. For a very modest investment, they can incorporate hands-on learning in their curricula; that's critical for students hoping to transfer to full-time ECE programs.

Furthermore, many are non-traditional students who have difficulties rearranging their work and family commitments for a 1-credit, 3-hour lab class. Doing the lab at home lets them take the courses they need to become engineers. Since distance and online learning is a big push for Virginia's community colleges - as it is for many two-year colleges across the country, online laboratory courses with portable lab kits help more students to enroll in engineering degree programs.

From a professor's point of view, the portable lab is a virtual godsend. Most engineering faculty do not have formal training in educational practices. New professors often struggle with how to teach and usually have to develop their own instructional materials. Lab-in-a-Box gives them a jump start since it comes with a curriculum and lab manual that's been revised over the last few years. Harried young professors don't have to reinvent the wheel. One of our engineering students actually created an automated grading program for lab reports, which helps ease the load on teaching assistants and faculty and lets students learn from their mistakes much faster. In short, the hands-on kit helps bridge the gap for professors and students.

Engineering has to be more than abstract theory and plugging numbers into equations. In my classes, I want my students to understand intuitively what's happening in the circuit. When I pose questions such as "Does the current flowing through the circuit increase or decrease as you increase the resistance of this resistor?", I can follow up in class with a live demonstration. I use my Lab-in-a-Box kit that I bring to class or I can have the students build the circuit to see if their answer is correct. With tools such as Lab-in-a-Box, they learn to trust, and validate, their understanding of systems and that's essential if they are to become good engineers.

It's been said by many in our field that it's easier to move mountains than modify an engineering curriculum. Slowly but surely, though, we're blasting through the boulders. Hands-on learning is the best way to keep all engineering students engaged. We need more of it, and online is one of the best ways to deliver the goods. Our ultimate dream is to make many of our tools available at a web site open to all engineering schools so that hands-on learning can be adopted more easily and all students have the best possible education in engineering.

Kathleen Meehan is ECE associate professor in the Bradley Department of Electrical and Computer Engineering at Virginia Tech in Blacksburg, VA. She can be reached at kameehan@vt.edu.