Taking AM all the way to the nTop

nTop is the most powerful computational design software currently available. VoxelMatters was recently invited to attend the company’s first annual Computational Design Summit ahead of this year’s RAPID + TCT, in Los Angeles. The company’s announcements during the summit were some of the most exciting and interesting to come out of the four days’ worth of industry news and networking events.

Bradley Rothenberg, the founder of the New York-based company, has been developing computational design tools for AM for well over a decade, having studied architecture at the Pratt Institute in Brooklyn. He started nTop in 2015 – initially as ‘nTopology’ – to ‘enable engineers to design without boundaries’. In May last year, nTopology officially became ‘nTop’, along with the launch of nTop 4. The company now has more than 100 employees (split between remote working and the headquarters on Lafayette Street), has raised more than $135 million in funding, and was used to generate 300,000+ designs in 2023 alone.

What is nTop?

nTop is a design software that enables engineers to take advantage of advanced manufacturing capabilities such as molding, milling, machining, casting, and additive manufacturing. According to Bradley, the company’s origins trace back to a fundamental realization that “manufacturing was no longer the bottleneck, but rather it was software holding back design.” This insight led to the creation of nTop, which aims to empower engineers to design topologies without limits, no matter how simple or complex – which is why the company has historically been referred to as ‘any topology’.

The software enhances design speed, manages complexity, and ensures reliability. “In a traditional process, you’re creating one design. And then when you need to make a change, you go back to the drawing board and redraw it. In a computational design process, you’re modeling all possible versions of that design [in one workflow]. And so you’re just changing an input parameter, based on what you’ve learned, to get something new in the model,” says Bradley. The software provides real-time feedback and boasts performance increases, ranging from 10- to 100-fold. This means complex modeling operations using other software that would typically take minutes or hours, or even break systems, are instantaneous in nTop.

The software allows for the creation of reusable design processes that remain robust even when inputs change. This reliability extends to integrating workflows with existing engineering software stacks. “Our modeling tech essentially captures a tree of operations [internally referred to as ‘Sequoia’] that represent the design intent – in a computer-understandable language. So we could use massive amounts of compute, in parallel, to run these models,” says Bradley.

nTop’s implicit modeling engine ensures that every solid body is described as a single mathematical equation – facilitating instant adjustments and iterations on designs. This leads to optimized performance through field-driven design, which allows for optimization based on simulation, test, or analytical data. The software also supports scaling by automating repetitive design tasks, batch-processing similar parts, and generating multiple design candidates during simulation-driven design.

“In additive manufacturing, there’s increasing interest in optimization and complex shapes, but we still lack effective design methodologies. For us, nTop is a key tool that helps us develop these methods. It’s crucial that they are adaptable and responsive to changing engineering concepts, technologies, and materials – allowing us to achieve the best results quickly, efficiently, and powerfully,” says Francesco Leonardi, Co-founder of Puntozero.

The implications of implicit modeling

First, for context, implicit modeling, often referred to as implicit surface modeling, is a technique in computer graphics and computational geometry for representing surfaces and shapes. Unlike explicit modeling, where surfaces are defined by vertices, edges, and faces (such as in polygonal meshes), implicit modeling defines surfaces implicitly through mathematical functions.

Implicit modeling naturally supports smooth surfaces and complex topologies. It is particularly useful for creating organic shapes, and smooth transitions between surfaces, and for performing Boolean operations. It can represent shapes with complex topologies (e.g. shapes with holes) without requiring explicit connectivity information.

One of the announcements made at the Summit was an integration with Materialise’s Magics software, with Magics 28 now able to natively read nTop implicit data – meaning that there is no longer a need for time-consuming meshing. This integration is currently in a limited beta phase and is expected to become generally available in the first half of 2025.

Prior to this integration, users would be able to design complex parts using nTop, but would then have to mesh them for build processing. Bradley outlined the inefficiencies of this more traditional workflow, and the effects of leveraging implicit modeling instead – which are, essentially, really fast processing and design iteration.

“For example, Wärtsilä makes these engines that are almost as big as this room [referencing the fairly large conference room]. They have a 0.5 m x 0.5 m x 0.5 m cylinder head of the engine that they’ve reduced the weight by almost half – combining several components into one. And so there’s a really strong business case to 3D print these components – speeding up the time to market from many months to a single week – instead of casting them. But, historically, they would take that component and mesh it and then bring that into Magics and try and print it. The mesh could take hours to generate from nTop, and then it might take days to import into Magics. And slicing, who knows if it’s possible,” Bradley explained. “So now, with the implicit integration, you export the implicit from nTop in about six seconds, then it opens Magics in minutes instead of hours, and then it slices in maybe a few hours. So I see this implicit integration as being really, really critical to the high-performance products of our customers.”

The far-reaching effects of nTop

With reference to the newest version of the company’s software, nTop 5, Bradley noted, “The new features we’re putting out into the world are only as good as the products that our [more than 400] customers can make [with the features].” These companies include those from Fortune 100s all the way through to startups, in more than 35 countries, that rely on nTop software to translate their designs into tangible products.

Customers across automotive, aerospace, defense, medical, consumer, industrial, energy, and even contemporary art, are now designing parts that have never before been possible to design, thanks to nTop. For instance, researchers at Lawrence Livermore National Laboratory utilized nTop to develop a nature-inspired system for liquid transport that relies on capillary action and surface tension. “What’s interesting is using engineering to make materials do something that the material itself can’t normally do – like how a resin can’t normally guide fluids along pathways, but by engineering a structure like this [with reference to the video below] it can be used to make better reactors,” says Bradley.

nTop’s customer base includes companies such as Ocado, Lockheed Martin, NASA, Northrup Grumman, Cobra Puma Golf, New Balance, Ford, General Motors, Sauber Technologies, DMG Mori, Wärtsilä, Siemens Energy, Aerojet Rocketdyne, RICOH, Renishaw, and MIT – a roster that speaks volumes about the pedigree of the company’s products.

“Building these geometries in traditional CAD would be a nightmare. CAD systems have a lot of limits. With nTop there are nearly no limits when it comes to complexity. When we come to the limit with our CAD system, we can go to nTop and create any crazy design we imagine,” says Benjamin Koch, Head of Engineering at Sauber Technologies.

“We’ve been pushing our nTop software to its limits as part of a collaboration with MIT’s Gas Turbine Laboratory, and it just refuses to break,” says Zack Cordero, Boeing Assistant Professor of Aeronautics and Astronautics at MIT.

Bradley envisions nTop as being THE tool for computational design – enabling the creation of high-performance products through advanced modeling technologies and integrations with artificial intelligence and machine learning systems. His dream is to see humanity’s fastest and most efficient aircraft and automobiles designed entirely using nTop – a dream that is seemingly within reach.