Project Description

The 3 Pillars of Engineering Understanding

3 Pillars of engineering

Photo credit – Institute for the Study of the Ancient World, CC

Do you ever feel like you can’t understand something? Even when it may be explained to you many times and it still doesn’t sink in? Every time you get stuck while learning or conceptualising something, theres usually an underlying reason. During the end of my Bachelor of Engineering degree (Mechanical Engineering), I discovered (stumbled on) the process to effective learning while studying.

This revelation came about during one of my third year subjects: I was continually reading about a concept but not truly understanding it at all. I sat back and wondered for a moment why this was the case. I opened a PowerPoint presentation of one of the lectures and it hit me immediately – I didn’t go through and understand the mathematics behind the process!

As an engineer, you learn to find reoccurring patterns in anything you do. This led me to trying to remember some point in the past when I had learnt something well and truly understood it. With a little mental effort a distinct pattern emerged from my memory! Every time I had grasped something well, I could easily explain three key components of the topic or principle. As you read through, see if you can successfully explain these three components to your friends (other engineering students of course, not someone else!) and you will know that you understand something well.

Let’s use the Root-Mean-Square (RMS) as an example to explain how the three key components assist in your ability to understand. The RMS is commonly used in electrical and mechanical engineering when analysing signals.
So what are the three components to truly understanding an engineering problem?

1 – Know how it works conceptually

Conceptual understanding is how you would explain this to someone who missed the lecture. Can you explain the theory to this person without going into unnecessary detail? This is also a good test to help you reinforce your knowledge and understanding of something if you can explain it well to another person.

Conceptually, the RMS calculates the average magnitude of a signal, and the RMS squared calculates the mean level that produces the same power as the signal.

2 – Understand the mathematics behind it

This is where the details matter. By understanding the mathematics behind a concept you begin to develop a keen idea of how it works and see the advantages and disadvantages. Textbooks LOVE displaying too manny unnecessary variations of an equation per page and when I used to come across these pages, I’d skip right on through! In the end, I would usually find myself having to revisit these pages and spend the time working through each equation step by step.

So, what does the mathematics of the RMS tell us?

It tells us the process to calculate the RMS – square each value of the signal, calculate the mean and take the square root. But why is it necessary to square the signal and take the square root? This relates to finding the mean value of a signal. Consider the random signal below.

In signal analysis, you will commonly encounter signals that have been measured which oscillate about a mean value. This mean value is often zero – for the case in the image the acceleration due to gravity has been removed, hence the oscillation about zero.

If you were to find the mean of this signal, you would get zero! While technically true, it does not provide anything useful to us. The RMS will tell you the average magnitude of the signal – by squaring all the values it will convert the negative values into positive values and you get a more accurate picture of the average magnitudes, and by squaring the RMS the average power present in the signal.

3 – Recognise the practical applications

Understanding how something works conceptually is great, but can you implement and apply it practically to solve a problem? Do you know where it can be applied? By knowing how to implement something, you are making it practical. The point of engineering is to make something of relevance that can improve society. By knowing where to implement the technique, you can avoid looking foolish.

The RMS can be implemented to analyse various signals, from electrical signals to mechanical vibrations. I was talking to a final year student a short time ago who was working on his final year project. He told me that when he was studying mechanical vibrations he couldn’t make sense of the concepts. His final year project involves applying vibration and when he was able to see how the concepts work in practice it all finally clicked for him.

Summing up

When I look back at the theories I understood during my degree, it all came down to these three things. If I understood the concept, the mathematics and know where it was applied in real life then I could really grasp the concept.

These three simple components will ensure you truly understand any subject or content. It will take you time to truly understand something (and that’s the whole point!), but now you have a strategy to implement and make it easier! If you get stuck with your understanding, go back and see if you can explain these three components to one of your fellow students.

Post a comment below if you have identified where you forgot a component or understood something well by addressing all three components!