By the time you read this, I will have completed my Fall semester undergraduate EMC course and will be starting the graduate level course soon. I know many of you will be doing the same and I wanted to give you an update to the work that Chris Semanson started in the Fall to incorporate modeling and simulation as a part of our undergraduate EMC course labs exercises. We are happy to report that things went well, we saw that the use of modeling and simulation added a new dimension to the course, and gave the students new insight into the “physics of EMC”! So – with that, here is Chris’ report.
How Electromagnetic Modeling and Simulation Is Being Successfully Used in an Undergraduate EMC Course
By Chris Semanson
It’s hard to believe that only a few months ago we (at the University of Michigan- Dearborn) started down a path to not only provide a simulation option to our students, but link it to our existing curriculum as well. Through this journey we identified a number of key points that allowed us to really take advantage of adding a “virtual” aspect to our physical lab. It’s these points; and along with how we chose the tool to use is what I would like share, with the hopes that this will assist others considering the same plans for their EMC courses.
The first of these points is that for modeling and simulation of any physical device, from a printed circuit board, to an antenna, the student has to find it relevant to their interests. This means that modeling at the undergrad level can be a great tool to explain what’s going on, especially when talking about how fields and waves propagate. A great example of this is shown in the figure below, where physically we have students measure and explore the functionality of a log periodic dipole antenna (LPDA) and the simulation tool allowed them to not only understand how it’s created, but how they function.
In Figure 1, we were able to successfully show how to design the upper and lower bounds of a LPDA in addition to how the antenna functions with each dipole pair being resonant at different frequencies (as indicated by the green arrows).
Another great example of closely linking the physical labs to the modeling experiments was using the following setup which examined the difference between a twisted wire pair and RG-58 coaxial cable and how each reacted in the presence of an electric field generated monopole antenna. (See Figure 2.)
Additionally, during our physical “crosstalk lab”, we examined the same situation but instead of a monopole as the noise source we used a source cable, an example of which is shown in Figure 3.
If the topic chosen is not relevant to their interests (which happened when we tried to introduce a more abstract topic like the examination of near field loop antennas and how the shape compared to the frequency), we found that the student tended to not be as engaged and tended to simply go through the steps of putting it together. The consequence was that when there was a problem with the simulation, the desire to troubleshoot it using experience gained from the lab because the link to the physical part wasn’t as strong. Figure 4 shows the result of a simulation which used a rotating field to show the current distribution on an electric shield of a near field loop antenna.
So, we used this feedback from the class constructively to tailor the future experiments, such as the final project, to more closely mirror that of the laboratory.
Lastly, when it comes to introducing these complex tools to the student we tried two approaches:
- Create extensive written “ReadMe’s and tutorials, which both outlined the functionality of the modeling and simulation program as well as the steps needed to complete the lab assignment.
- Create short, 5-10 minute videos which allowed the students to see the steps needed to create the experiment real time.
The first approach we found worked satisfactory for smaller less complex labs, but we found that as the experiments got more complex the amount of work to create a thorough tutorial in how to complete the lab grew exponentially. We found that by creating videos and posting them, the students were able to pause and follow along with the video at their own pace which greatly reduced the anxiety and difficulty they were having with larger more complex simulations.
It’s our hope that anyone looking to add a modeling and simulation aspect to their electromagnetic curriculum can use our approach and lessons learned, to create a rich educational environment and take their class to the next level of understanding the complexities behind electromagnetic compatibility.
I would like to thank you all for your interest and feedback on “The View from the Chalkboard” over the years. This month’s column is my last for the foreseeable future. I have been honored to contribute to In Compliance regarding my experiences of an EMC educator. It has been a wonderful for me and for my students to participate in sharing our stories. Until next time, wishing you all the very best! – Mark Steffka
