What is topology optimization?

Topology optimization refers to software that takes advantage of the design freedoms offered by additive manufacturing. It is a generative approach, so multiple design configurations are created for experimental testing without added design work. Plus, the degree of physical testing to achieve an optimal design is reduced or eliminated by pushing iteration to the software side.

One of the first topology optimization programs was solidThinking from Altair.  With Solidthinking, a designer would define load information and the software would use a mathematical method to generate a design based on that data.  The software indicated where non-vital material could be eliminated from the design.

In general, topology optimization programs enable designers to create a design that is strong, lightweight, and minimizes material usage. Often, the result is an organic shape, like something one would find in nature.  Because of these organic shapes, the best manufacturing tool is an additive manufacturing machine to build the design.

How topology optimization works:

–The first step is to define the “design space” that represents the maximum volume a part can occupy. In this brake pedal example, the design space is represented in orange.

–Then the loads defined by the designer are applied and analyzed to offer several part design options. In this example, the brake pedal is supported at the end, which can pivot.  (In this example, the result looks like an organic truss structure.)

An example from General Electric is an engine bracket where the software removed 84% of its weight using topology optimization. This part went on to be 3D printed out of titanium using selective laser sintering. The lower weight of the bracket was estimated to save the airline industry $31 million dollars through energy efficiency from just one small part.

–The topology optimization program delivers a result that meets the defined criteria for a designer.

One of the key benefits of topology optimization is its ability to cut excess weight out of a design. Thus, the aerospace and automotive industries frequently use this software during design.

Today, many CAD programs include a topology optimization module.  Companies that offer topology optimization software include Altair with solidThinking Inspire, Ansys, Autodesk Fusion 360, Dassault Systèmes, PTC, and Siemens among others.

Autodesk Fusion 360 

In the Siemens offering for example, engineers and designers can blend topology optimization with traditional CAD data. The topology optimization software is a generative design technology that streamlines a product’s shape by automating weight and material reduction while still retaining structural integrity.

Generative design is a variation of topology optimization software. The major difference is that it “generates” several design options based on input constraints such as material, function, weight, and cost.

Generative design is a computational design approach that synthesizes parameters and objective goals into an iterative algorithm to generate optimal structures.

An object’s optimized form is generated by first defining forces exerted on the object, just as in topology optimization. Design goals and guidelines are then dictated before allowing the software the processing time to iteratively arrive at an “optimal” solution. During each iteration, a structural analysis is computed, and those regions that will experience less than a threshold stress or deflection are removed. This process repeats until one or more designs are presented to the designer for final evaluation.