I’m old enough to have started my college education by drafting with a 2B pencil, a few right-angle triangles and a protractor…and young enough to have learned that method side-by-side with computer aided design (CAD). Although the hand drafting class was my favorite that year, the CAD education was by far the most productive. As much as I liked the tactile feel (and the nostalgia) of the drafting board, the speed, accuracy and pure precision of computer aided design just blew away the slow and imprecise method of hand drafting, in my opinion.

Digital drawing

As big of a step up as CAD was compared to hand drafting, the design process was still much the same in those early days. To grossly oversimplify things, CAD simply offered an easier way to draw lines and plot out drawings. We were still prone to the same mistakes that were prevalent in hand drafting – labels that didn’t match, inconsistency between plan sheets and plain old design errors. In fact, since CAD design was faster and simpler, we were probably MORE prone to these mistakes because we weren’t as thoughtful and careful.

Digital modeling

Within the past 5 to 10 years another big leap has been made in computer aided design, which I believe has provided just as much benefit as that first leap from hand drawings to computer. The advance I speak of is that instead of simply mimicking hand drafting by using a computer in a two-dimensional fashion, current software allows us to design in a powerful three-dimensional way. Instead of just drawing lines, we create three-dimensional surfaces and models that are linked together and “interact” dynamically. No longer is a new trail simply two parallel lines with a grey hatch in between…now it has a thickness and is linked to the new vertical centerline that I design in a profile view. If the layout of the trail is shifted, then the centerline shown on the profile view shifts as well – if I move a point in the profile view up or down, the topographic grading lines shift in my plan view.

My top 3 benefits

What exactly are the benefits of this newer way of producing designs? I’ll give you my top 3 ways that this has improved my designs.

1. Assures consistency. Construction plans often try to show the same feature in different viewpoints to try to give the builder a clear picture of what it is that their supposed to build. So a street will be shows in a plan view, a profile view and a cross section view. Each view shows a different “slice” of the same road. With a three-dimensional model, all of those slices are linked together, so that if I revise something in plan view, the profile and section views change automatically. No more do I have to worry about manually revising each view within the plans – it’s done automatically. The views are dynamically linked together.
2. Improves speed. So even if I did remember to go back and change all the views when I tweak my design, that still takes time. And time is not just money…it’s missed deadlines…it’s annoyed property owners…it’s a grant funding window. Being able to make revisions to a plan in a more efficient way has obvious benefits to everyone involved. ‘Nuff said.
3. Better designs. When you’re able to view your design in a three-dimensional way, you’re able to see things that you couldn’t in two-dimensions. And this added information allows us to produce more accurate and more effective designs. To me, this is one of the most significant benefits of designing in three-dimensions so I’ll take a deeper look at that in a future post, but the idea is that if I have more information at my fingertips then I can better tailor my design to match existing conditions. And since this information is able to be viewed and comprehended in a visual three-dimensional model, I can make adjustments to the design that I never would have even thought to make previously. The end result is something that often is easier to construct and solves more problems than I ever could have before.

Do you use three-dimensional modeling in your designs? What have you found to be the benefits from your perspective? What have been the drawbacks? I’d love to see your comments below or contact me directly.