FAME blog: Optimized is the goal

FAME blog: Optimized is the goal

Atte Heiskanen, Structural Analysis and AM Engineer, Etteplan

Additive manufacturing is a manufacturing technology enabling designers to create highly complex and optimized shapes for multitude of applications. This coincides with the challenges we all are facing in the modern world, which we need to tackle by driving towards energy efficiency and other green values. Here AM can play significant role, as the optimized structures can lead to unprecedented performance. This enhancement of performance can often be a requirement to justify the use of additive manufacturing in our applications.

Knowledge is the key

To address challenges related to modelling and designing such highly optimized shapes, multitude of software companies, both those well established as well as fresh start-ups, have entered the market to provide new solutions for design engineers. These days, some of these software tools are already on very high level, allowing us to create structures and solutions like we have never seen before. While the software tools are there already, our knowledge of them often is not. One of the main factors limiting their use is that we simply do not know what to do with them. These software often take the design work closer to programming than traditional CAD design, resulting in quite a steep learning curve for any old-school designer looking to transition.

Geometry creation in traditional CAD (left) vs. nTop (right). Instead of utilizing sketches and common CAD operations such as extrude, geometries in nTop are created using ‘blocks’ representing different functions and making the design work similar to programming.

The programming-like nature of these tools is what really differentiates them from others. The possibilities we can utilize them for are close to limitless. Just like with any programming language, we essentially have this large sandbox, within which we can create anything we want using the tools provided. Because the parts are in the end created by the “code we write”, it is very convenient to for example automate design workflows or use data from different sources to drive geometrical features.

Not just topology optimization

When talking about optimization and additive manufacturing, people often think topology optimization, which of course is a good tool to create for example lightweight brackets. However, it’s use is quite limited, as it only allows us to optimized load bearing structures. The results also often are branchy geometries which would not be suitable for for example pressure applications.

If we take a look at broader scope, we can strive to optimize any feature or functionality of our components, be it weight, flow or heat related properties, or even the manufacturing cost of the component. With the tools available now-a-days only imagination is the limit for the highly functional components we can create.

Components optimized for flow and heat properties (left), weight (middle) and manufacturing cost (right)

Modern design software, such as nTop, make this extremely efficient. We can use any data, from simulations or elsewhere, to drive geometrical features of our designs. An example of this would be topology optimized bracket that was to be manufactured with 3D-printed sand cast molds. In casting, it is often desirable for the structure to have more material near the feed point. Creating geometries like that in traditional CAD, especially when considering all the related fillets and such, can be quite cumbersome. However, with modern design software we can just determine the feed point and automatically control the part thickness based on the distance from the point.

Topology optimized bracket optimized further in nTop to make the casting of the component easier.

Just scratching the surface

The cases presented in this post only scratch the surface of what is possible. To get the most of these magnificent new design software available, they need much more exposure for designers to get ideas what actually can be done with them. Currently there often is a major disconnect between the people who understand the capabilities of these tools and those who know ins and outs of the products. This is the gap we need to close to find optimal solutions for increasing amount of applications.