What This Seat Bracket Says About the Future of Automotive Manufacturing
General Motors created a 3D-printed version of a seat bracket using generative design tools. This technology pairing will influence how cars are brought to market in the future.
General Motors (GM) says that it has reduced a total mass of 5,000 pounds across 14 of its vehicle models since 2016, many of them shedding more than 300 pounds. The 2019 Chevrolet Silverado alone is 450 pounds lighter than the 2018 model.
Though these weights savings have been the result of material and technology advancements, the automaker will soon implement other tools to achieve its lightweighting goals. Namely, additive manufacturing (AM) and generative design.
The seat bracket pictured above is one example of how GM will think about car parts in the near future. This proof-of-concept part was designed with Autodesk’s Fusion 360 cloud-based generative design software and 3D-printed in metal. The additively manufactured bracket is 40 percent lighter and 20 percent stronger than the original part. This bracket offers an illustration not only of what car parts of the future may look like, but also how they will be designed differently.
“Traditionally, we would start with the last version’s model, maybe tweak it a little bit and come up with two or three design iterations,” says Kevin Quinn, GM’s director of additive design and manufacturing. “We might achieve a 5 percent mass saving and make it a little stronger.” But generative design entails a different process. Rather than modeling the geometry directly, designers set inputs around constraints, allowing the software to propose potential geometries.
In the case of this seat bracket, the generative design process resulted in 150 design iterations. Aesthetics, manufacturability and simulation results played a role in selecting the final design, in addition to its reduced weight. The design chosen (and the one pictured above) was actually not the lightest option, but it represents the best trade-off between these factors.
This new workflow from generative design to additive manufacturing will play a role in how future vehicles are brought to market—first for high-performance motorsports, but later for consumer vehicles as well.
Why engage this workflow? Why pursue lightweighting at all? Because GM sees the future as an electric one. Among other benefits, lighter weight means greater range for electric vehicles. That’s the bet that GM is making over the long term. Read Brent Donaldson’s reporting for Additive Manufacturing for a closer look at this story.
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