Automotive Design & Production is the one media brand invested in delivering your message in print, online, via email, and in-person to the right automotive industry professionals at the right time.
Issue link: https://adp.epubxp.com/i/517278
39 p HardMarque Future Factories, an Australian industrial design shop, used Inspire to lightweight a piston made of titanium in an additive manufacturing process. After the piston design was refned in another CAD system, the fnished piston was 23.5% lighter than the original stock piston. Yet it was just as strong. analysis [FEA] process. It creates a material layout within a given design space, for a given set of loads and constraints, in the most efcient way to meet the required performance targets." Interestingly, FEA and topology optimization work toward optimal designs from opposite directions. In FEA, a part shape is imported, loads and constraints are defned, and then a simulation confrms whether the shape satisfes the loads and constraints. In topology optimization, the loads and constraints are defned frst, a volume that the part will occupy is defned, and then from the simulation, the software generates a part shape that satisfes the loads and constraints while minimizing the design goals of minimum part weight and maximum part stifness. The topology optimization in Inspire starts with solid geometry, which can be imported directly for all major CAD systems or imported as a neutral CAD fle (such as IGES, Parasolids, and STEP). Then the design engineer inputs loads and manufacturing constraints. "The tricky part, which requires some intuition," says Vernon, "is in how the model is loaded and supported to accurately depict how the fnal part will be used." At this point, the software takes over. All the meshing and other FEA operations for topology optimization are done in the background. These operations are basically a series of iterative analyses that vary the density of each element in the mesh—element by element. The solver determines whether the specifc element needs to be in the design in order to satisfy stifness, lightweighting, and other design requirements. "The density of the material is essentially a variable," explains Tony Norton, executive vice president, Americas, for Altair ProductDesign, Inc. "Material is removed from regions that are less essential for carrying the loads." The FEA module in Inspire lets design engineers see how loads are applied and how the model will move as a result, as well as perform some basic modal analysis, such as natural frequencies in normal modes, and see mode shapes. Designs fnished in Inspire will still need to be validated (post analysis) using an advanced analysis tools, points out Vernon. PRETTY, AND PRETTY EFFICIENT RESULTS Think of topology optimization as a way of carving out excess material in a design. "Design lightweight in, instead of engineering mass out when starting with the ideal solution," says Vernon. Sure, a block of metal will work for an automobile pedal, but a ribbed piece of plastic will be lighter, cheaper, easier to make, and probably just as strong. "Inspire helps design engineers follow the functional and resource-efcient design rules found within nature, an approach often called 'biomimicry,'" continues Vernon. The resulting designs often look like biological structures found in nature, such as honeycomb, skeletal, and fractal shapes that feature curvy surfaces, bends and twists, pattern repetition, and the use of loads in tension. These shapes that are easily produced using additive manufacturing methods. For example, HardMarque Future Factories ( hardmarque.com ), a Melbourne, Australia-based industrial design and additive manufacturing studio, used Inspire to lightweight a piston made of titanium in an additive manufacturing process. The fnal piston design weighed 289 grams, 23.5% lighter than the 378-gram original stock piston, yet just as strong. "The lighter your internal components are, the lower your carbon footprint is," says Nick Hard, director of HardMarque. "And not only that, because it's additive manufacturing and not subtractive manufacturing, you are not wasting 90% of a block of metal to achieve the fnished product. You are only consuming the material you need for the product."