The Triangle of Achievable Engineering
You want High Performance! Absolutely. You want it Cheap! Of course. Only the best in Quality! We agree. Now let me show you this cool new material we call Unobtainium. It’s just the ticket to smashing the triangle of achievable engineering to get everything you want. 😉
Of course we always want the best, and we also want it for cheap. That’s perfectly natural, yet, not usually realistic. Reality says all our engineering — whether consulting or in house design — requires a balance. As a graphic for discussion, we have this “Triangle of Achievable Engineering”. We don’t claim authorship, but we have mutated it to meet our need.
What Is This Triangle?
The image shows 3 sides of a triangle, each with a name. No one is more important than another, because they all exist in every project. That is the catch, however. While they all exist, they do so at different levels. The triangle is there to remind us about the relationship.
With each customer, and each new project, we talk about the relationship of these 3 triangle legs. In essence, you can pick two.
What? Only 2 ??
Understand, of course, that every project is different, and these words mean different things in context of each project. In development, for a massive custom machine Low Cost is very different than for a small plastic widget. The same is true of Quality and Performance. They mean different things for each project.
We call it the Triangle of Achievable Engineering because each leg opposes the vertex of the other 2. For instance, if you want top performance and super high quality, then these typically exclude low cost. A Mercedes S-Class Coupe fits the category of high performance, and supposedly they are excellent quality — but cheap? Not so much.
How about High Performance and Low Cost? Think about cheap children’s toys for an example. They’re great — till they break.
What about Low Cost and High Quality? An example is with bolts. While a Grade 2 bolt can be high quality (for it’s rating) and low cost, it won’t perform like a Grade 8.
So, now we have some examples, let’s talk about each leg of the triangle and why we take sides.
Exploring the Triangle of Achievable Engineering
Engineering For Performance
We’ll start with performance, because as an engineer, this one is my favorite. Faster, Lighter, Stronger, and More Efficient!
There is a lot that falls into the category of Performance. Maybe it is Faster, or Lighter, or Stronger, or any other descriptor. Your product will dictate what “Performance” means, then translate that into the Triangle of Achievable Engineering. Weigh the performance aspects against the needs for cost and quality.
One of my favorite examples with this triangle is that of automotive engines. If you want super performance, then pick a top fuel dragster. Though it’s really expensive, and it’s super high output, it will not last long — like driving your car on a big road trip. The goal of a top fuel motor is just a few seconds of maximum performance without blowing apart. In that arena, that’s quality, but in the “let’s go camping” arena, a few seconds doesn’t get you very far. Performance is truly in context of the goal.
Performance can also be an attribute of art, or other equally sublime characteristic. These are not often thought of as “performing” traits, but there is a blend of Science, Function & Style that make things work well. (And, incidentally, blur the achievable engineering line between Performance and Quality.)
The Cost Aspects
There are 2 aspects to cost. First, the cost of completing a project; then Second, the cost of the product once it goes into production.
Let’s talk about project cost first. All the expenses going into creating the product, including the Engineering, Development, Prototypes, Manufacturing, etc., are costs of the project. We control those in part by the project scope, but choices from the Triangle of Achievable Engineering also enter in. For instance, if we ask for super high quality, then we must spend more time thinking through all the different ways the product becomes truly a quality product. And, probably work through more prototypes. On the other hand, we can drive down project cost by reducing our expectations for optimization (for instance, weight reduction).
Production Cost is a very different animal. This is the price — how much it costs for each widget to be made. Design and engineering to achieve a sweet low-cost final product is almost always a target. However, optimizing usually increases project cost, while it reduces production cost.
Please note that there are 2 big factors driving product price that are independent. First, Quantity is king. Make more of almost anything, and you’ll reduce the per part production cost. Second, manufacturing method. If you want a particular manufacturing method, for instance Injection Molding, then you constrain your production cost — which may be up or down depending on the Quantity.
So, when we talk about Cost with the Triangle, we have to consider both project and production.
We’ve already spoken a lot about quality. From quality in software, to giving quality in customer service. We believe Quality is what the customer says it is — which brings us back to knowing your customer and designing the products — completing the engineering — to meet their needs.
While it’s a pretty nebulous term, customers identify Quality pretty easily. If your customers demand it, then your choice on the Triangle must reflect it.
Interestingly, Cost and Quality are more often traded than Performance and Quality. That is certainly something interesting to think about.
How Do We Use The Triangle
The triangle is a good conversation piece, though it’s really rather meaningless by itself. It’s in context of a new product or project, that it becomes meaningful. And when we need a Quote for an Engineer project, it gives some very good direction.
I challenge you to contemplate how your project will turn out as you choose different pairs of triangle sides. It can really be an eye opener.
Deeper Into Achievable Engineering
If you want to go deeper with this as a tool, you can place a dot within the triangle indicating how to balance the 3 sides. Remember we mentioned that all 3 are present in every product, just at different levels.
Think about the focus by placing the dot. The closer it is to one side, the more focus is on that particular activity. Some say, “That’s easy, just put the dot in the middle”. While that seems obvious, that means nothing is important, so make it generic and excel in nothing.
It’s when we think about the engineering required for high Quality that we understand the trade-offs with Performance and Cost. The Triangle of Achievable Engineering becomes a pointer for our thoughts. It’s there to make us think about what is really important, and what we’re willing to sacrifice to get it. So much of engineering is trade-off’s, and this triangle is a good tool to help guide decisions.
The above discussion on balancing constraints is just as one application — Performance, Cost, Quality. While these measures make a nice tool for focus, it’s not limited to achievable engineering. Why not use the same triangle principle in other focus areas? Here’s another example of managing conflicting constraints, with a twist of the triangle. It comes up a lot.
Good luck with your projects and exploring the triangle. Until we discover the source of the mythical Unobtainium, there is always compromise and balance somewhere.