Ever wondered how those buildings with web like arches and products with futuristic looking structures are even made? It’s all through generative design! Which can be performed right from the desk of an engineer!
What is Generative Design?
Generative design is an iterative design process which utilizes software and calculations to generate multiple solutions with respect to constraints and multiple variables. In engineering, generative design is partly carried out by a specific technology found in CAD software such as SOLIDWORKS and Autodesk Fusion 360, called topology optimization. Generative design and topology optimization cannot be used interchangeably though, Topology Optimization generally finds a single solution, whereas generative design can use topology optimization and other tools to generate a set of solutions. To put it simply, generative design builds on the foundation of topology optimization to better come up with more fine-tuned solutions.
What is Topology Optimization?
Topology Optimization is a set of processes and software that optimizes a parts structure with regards to user defined constraints and external forces. Although the software optimizes the part, it can only successfully do so when the engineer correctly defines weight constraints, areas of optimization, and loading scenarios. The CAD model shown below has been optimized to use less material while also maintaining the structural integrity to deal with external forces.
How is Generative Design Executed?
In a CAD application such as PTC Creo, a part can be optimized by inputting engineering and non-engineering requirements (such as material availability and cost), the software will then optimize the design and offer a set of solutions, which the user can choose to their liking. Depending on the software, the design can also be optimized for a specific type of manufacturing, such as additive manufacturing or “3D Printing”.
In Fusion 360, a generative design study can be set up in just a few simple steps. First, the model can be analyzed using Finite Element Analysis (FEA) on the original model. In the function tree, depending on the number of parts in the model, multiple geometries or parts can be selected to either preserve their shape or be subjected to the topology optimization. In doing this, the software will avoid certain regions where it will not modify the structure and other regions where it absolutely must.
Next, constraints can be applied to different regions to simulate real life scenarios, where a component may be fixed to a surface and can’t move. Load cases are then applied as needed to the correct regions and the user can also define specific directions. The most important part of the process though, is defining the studies’ “Objectives and Limits”.
The user can select to minimize mass or maximize stiffness as their object and a safety factor as the limit. In doing so, the software knows to reduce mass or maximize safety while referencing a factor of safety. A factor of safety establishes a limit to express how much stronger the design is than the intended load.
From here, the difference between generative design and topology optimization can be seen. The user can now choose which manufacturing method the component will be fabricated by, as well as the material type. The parameters and variables are now all set, and the study is ready to go! Multiple studies are run if needed and different outcomes are produced. The user can then choose or filter the different designs using a filter and FEA results of each different outcome.
What’s the Link with Additive Manufacturing?
When paired with additive manufacturing capabilites, the creativeness of the design and manufacturability is almost endless. The technology of 3D printing offers a wider range of possibilities in manufacturing, when compared to traditional subtractive manufacturing, such as a CNC Mill. A component like one shown below would be almost impossible to manufacture using a CNC mill due to multiple areas the end-mill could not reach and the organic shape produced by generative design. The final design cut weight by 42%, which reduced costs due to material pricing.
Additive manufacturing is also used for rapid prototyping for components. Rapid prototyping can be seamlessly paired with generative design as it offers a quick design solutions which can then be 3D printed in a matter of hours. In addition, 3D printing is a quick way to test the multiple generative design outcomes in a real-world scenario. With the case of complex structures, a CNC mill may take many hours of labor and incur massive tooling and labor costs. Which in turn, can be very detrimental to a business when coming up with a product or providing services.
With all of the flexibility in generative design, the process allows engineers to be much more creative without sacrificing the components intended function. Generative design allows the engineers to focus their skills on solving complex designs, as opposed to manually revising the design and spending time on the revisions. When paired with additive manufacturing, the opportunities for rapid prototyping and testing are endless. Some may say these two technologies were made for each other. Generative design continues to push the boundaries of engineering and is a very promising outlook for the future.
Catania Enterprises provides product design services that can be optimized using generative design. Our team of engineers are experienced in providing optimized solutions that satisfy the customer’s needs while reducing manufacturing costs.
Please Contact Catania Enterprises for more information on how we can help you bring your ideas to life.
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