Real-world uses of CAD software & 3D scanning

It can’t be emphasized enough just how much easier the design and engineering process is when using CAD software. From the initial concept and design stages, all the way through the analyses of components and assemblies, not to mention the actual manufacturing and packaging of the resulting products.

Being able to make changes to dimensions or shapes, whether minor or major, and then watch as those modifications propagate across the entire design in the blink of an eye, is of inestimable benefit to today’s modern design workflow. There’s no way for the same to be done via 2D paper and pencil.

Submillimeter-perfect accuracy

Today’s computer aided design solutions give you the power to create models that precisely represent their real-world counterparts, within a few microns’ tolerance. Unlike with drafting and 2D drawings, by using CAD software, you’ll never waste time with redrawing designs from scratch or creating new layouts from specific angles.

When you’re working in 3D, your hands are never tied to a standard six-view layout. Choose from hundreds of possible angles at whatever levels of magnification you wish.

Most likely whatever you’re designing won’t be the one and only product you create. And this is where computer aided design software shines all the more, giving you the power to easily build up templates and libraries of components that you’ll be using again and again. These can also include custom parts and accessories, such as in-house-designed electronics or fasteners, or off-the-shelf components.

All of these can be simply dragged and dropped into your designs, as needed. This makes your future design workflows that much easier and faster, dramatically reducing the time and effort needed to bring your plans to life.

Leveraging your CAD models to the max

Once you’ve created your CAD models, a wide range of usage possibilities exist, well beyond simply manufacturing. For example, let’s say you want to quickly create a range of new prototypes with various kinds of modifications, maybe even scaled versions of the original, with additional components and features added on.

By starting off with your existing CAD model and designing from there, you’ll not only have a solid foundation for your work, but you’ll also shave days if not weeks off your prototyping workflow.

FEA, CFD, and beyond

Another potential avenue is a simulation, such as FEA (finite element analysis) or CFD (computational fluid dynamics) testing. By taking your CAD model and bringing it over into one of these systems, you can perform essential stress and fatigue analysis testing, for analyzing and improving aerospace or automotive components, among others.

Importing your CAD model into a CFD system gives you the power to conduct aerodynamic/hydrodynamic testing, a critical stage of the design process for many clients, from motorsports to aviation to maritime industries, and beyond.

Effective packaging design

With your CAD model tested and ready for manufacturing, it can also be used for creating custom product packaging for shipment and well as display. Having a precisely-dimensioned CAD model of your product makes it easier to produce inner packaging that cushions and protects the product, especially fragile and shock-sensitive items, with corrugated cardboard, foam, and microfoam as possible mediums.

Not only for protective purposes, such CAD-accurate packaging makes it possible to optimize space and reduce total shipping weight, significant factors when it comes to producing and shipping hundreds if not thousands of a given product over time.

Flawless inspections in minutes

One of today’s most potent uses of CAD is in quality inspection. Particularly when combined with 3D scanning, computer aided design software can be an immensely useful tool for the most crucial steps along the QA/QI continuum, on the assembly line, at the loading dock, upon taking delivery, or out in the field.

How it works is simple: by using a 3D scanner to measure your object or part, you then compare the scan with the original CAD model to identify any deviations outside the acceptable range.

Although it’s entirely possible to manually measure parts of components and use these for comparisons, unless you’re working with geometrically basic shapes, there are bound to be gaps in your measurements. Let’s say, for example, what you’re measuring has curves, recessed surfaces, thin edges, not to mention if it’s made of soft, easily-deformed materials.

As mentioned above, before using CAD software, engineers around the world depended on pen and paper for their design work. That meant that every single line and curve or other shape was carefully sketched out using rulers, protractors, and other drafting instruments.

When it came to calculations, whether that was pressure within pipes, electrical voltage through wires, or aerodynamic forces across a section of wing, these were all done manually. And that means being open to human error.

Why digital eclipses paper

As well, these technical drawings were susceptible to damage or destruction, not to mention being cumbersome to store and transport. CAD software changed all that. Now design drawings are no longer limited to a physical piece of paper, or even 2 dimensions, and they can be viewed and edited by colleagues working alongside you or on the other side of the planet.

In nearly every respect, digital CAD models are superior, certainly when you need to safely archive them for future use, for example, in the event that either the physical CAD design or the object itself no longer exists. With an accurate CAD model on hand, virtually any part or assembly can be brought back to life.

Among the most popular CAD programs on the market, two main modeling paradigms exist: parametric and direct. Let’s take a quick look at each one.

Parametric modeling

In use since way back in 1987, this is normally what people think of when they talk about CAD modeling. With parametric modeling, you build up a 3D geometry piece by piece, using 2D sketches to create 3D features.

Along the way, you’ll carefully add in all the features and constraints needed. As such, parametric modeling requires diligent planning, especially as your model’s feature set grows into the hundreds and beyond.

This kind of history-based modeling is what really sets parametric modeling apart from the other primary method: direct modeling. With parametric, the software remembers the features you’ve given your model in the exact order in which they were given.

In this way, it’s like a computer program, where sequential instructions exist, and every time you want to add a new feature or change an existing one, every single aspect of your model will be affected.

Although parametric modeling is extremely powerful, it suffers from several weaknesses: first of all, the very steep learning curve, requiring months and even years of experience before proficiency is achieved. Not a problem for existing users, but new engineers face a daunting uphill climb before ever beginning to reach fluency in this arena.

Yet perhaps the greatest hurdle is parametric modeling’s history-based approach, which can easily throw a monkey wrench into your plans unless you understand precisely how the model is built and develop carefully with all those constraints and specifications in mind.

Direct modeling

Being the relative newcomer to the CAD design market, yet undoubtedly the most attractive in contrast with parametric modeling, direct modeling is often the choice of today’s young engineers.

With this approach, you’re working in a WYSIWYG (what you see is what you get) environment, building and editing your models by moving around the actual faces of the model, rather than editing feature dimensions and sketches, as you would with parametric modeling.

As a result, direct modeling excels at rapid prototyping and design work, particularly in industrial design, where workflows need to adapt to changing requirements and specifications, without having to bear in mind extensive design histories.

Many proponents of direct modeling strongly believe that this is what truly sets their workflow apart from parametric modeling. Because with direct modeling, whenever it’s time to make changes, whether modifications or adding in new features, there’s no danger of breaking anything, unlike with parametric modeling, where such alterations can result in extensive disruptions.

Pluses and minuses for each

That said, both methods have their strengths and weaknesses, and most of today’s mainstream CAD systems offer some combinations of parametric and direct toolsets. For example, several packages offer direct editing tools, yet with features still being created in the model’s history tree, which means that these can’t be considered as “pure” direct modeling systems.

Ultimately, it’s up to you as the user to explore the various programs available and decide for yourself what’s most ideal.

Veteran CAD users may wish to stick with parametric modeling, simply because they’ve already invested huge swathes of time and energy there, whereas new engineers should seriously consider direct modeling, unless their company or circumstance requires them to choose otherwise.