Topology Optimization: Create the best version of your parts!

An introduction to Topology Optimization

Simply put, Topology Optimization (TO) is a process that optimizes a part by reducing the unnecessary material. It uses mathematics to improve the geometry of a part to figure out where an object needs material and where the material has no use for the efficiency and performance of the later product and is simply there for aesthetic reasons. The goal of TO is to create a part with the best possible performance by reducing as much material as possible.

Topology Optimization is often connected to Additive Manufacturing since 3D printing can easily produce optimized parts. 3D printing or Additive Manufacturing is a growing manufacturing technique, whether for prototypes or end-products. It gives the designer the freedom to create the part, save it in a 3D file and then send it to print. The printer creates the object layer by layer to create the part. Giving businesses the ability to transform a digital object into a physical form. There are different kinds of printers and materials that can be used. For printing in plastics, using selective laser sintering technology is best. For metal parts, DMLS or Binder Jetting technology should be used.

Compared to 3D printing, traditional manufacturing methods can also work with TO models but generally have higher limits and cannot go further when it comes to Topology Optimization. The freedom of Design, which Additive Manufacturing offers, is the complementary process for exploiting all of the advantages TO can offer. 

TO is becoming increasingly used as many industries work with it to create strong parts despite using less material. To name a few fields like aerospace, biochemical, civil engineering, medical, or automotive all use TO. In their use case, Altair showcased how Topology Optimization is reducing 500 kg from a plane. That weight loss automatically means less consumption, since the higher the weight of a plane the more fuel is needed. 

Workflow of a Topology Optimization

Even though there are various TO methods, the most common one is  FE (finite element) based technique. The actual optimization of a part is usually in the last part of the design process. 

First, the user has to define the part of the object that incorporates the max. volume the object can occupy. This is also called “design space.” Then the user will set the external forces that the object should be tested in. This is the hard part of the optimization, as it is essential to know precisely which external forces are impacting the part. It is also not enough to know which forces. The importance is to know how big the forces are and how to define them. If the settings are added, the TO algorithm finds, in the following simulation, spots that can be removed and still withstand external stress. 

The software then proposes various design ideas by reducing the used material while the design can withstand external forces. Every time a part of the material is being removed, the algorithm checks if the object would still work under the set stress. After the user is satisfied with the result from the simulation, the object is then checked for printability. Sometimes the user will customize the design again to make the object look more aesthetic than the result from the simulation. 

Topology Optimization vs Generative design

Topology Optimization is often described as a form of Generative Design. But where exactly do these two methods differentiate? Generative Design creates multiple possible designs which is helpful when the designer is unsure which kind of shape or design is needed. TO only focuses on a single design and all the possibilities for optimizing it. For example, when a shape is picked from the Generative Design selection, TO can be used to optimize the shape. This means that TO is used by Generative Designs. However,  TO never uses Generative Designs, as it needs a single design input to work with.