The next big breakthroughs in additive manufacturing – also called 3D printing – won’t be as showy as notable recent examples of printed houses and cars, but they will be no less dramatic in their impact. The process of taking ideas from concept to reality is being transformed by software, promising to shrink design times, improve production efficiency and change the way many everyday items look and behave.

Design and simulation capabilities are merging, and software is taking a more active role in guiding design decisions. Designs can now also increasingly be tested in software without going through a prototyping stage, which cuts down on time and waste. Finally, additive manufacturing machines enable some products to be produced that are impractical in conventional manufacturing scenarios.

Speakers at Dassault Systèmes SA’s “Science in the Age of Experience” conference in Boston this week detailed how this integration will accelerate additive manufacturing’s path into the mainstream, bringing with it a host of innovations that will make products of all kinds cheaper and more efficient. Attendees had the chance to gawk at a 3D-printed SUV Dassault co-designed with Oak Ridge National Laboratories (above), but in conference rooms the discussions were about more mainstream – and revolutionary – changes that are in the works.

How does additive manufacturing change things?

In essence, many things look the way they do because of educated guesses. Lacking the tools to thoroughly optimize designs, people make the best choices they can based upon the information they have. Thorough testing is impractical in many cases. This doesn’t always lead to the most optimal decisions, though. A human may decide to put six rivets in a car door panel to play it safe, but a computer can determine with precision the only three are needed.

Additive manufacturing is a way to test new ideas quickly and with a minimum of waste. Three-dimensional printers use melted composite materials applied in layers to exactly match a computer model. There is no trimming or cutting, so there is a minimum of waste. Additive manufacturing machines can also easily create elaborate curved shapes that are difficult to manufacture in an angular assembly line. “You’re designing shapes you wouldn’t have designed before and then manufacturing them,” said Rani Richardson, a business experience consultant for Dassault’s Catia line and an expert in additive manufacturing.

James Fort, a Dassault product manager, showed an example of how a simple support truss can be re-imagined in this way to eliminate half or more of the materials and weight while actually strengthening its capacity. “It’s about generating a functional design using optimization,” he said.

Designers begin by specifying constraints, or physical limitations of production or use. Computer models can then test designs to identify which ones meet all the requirements with the minimum of extraneous material or manufacturing effort. Unnecessary material is continuously removed from the design and new shapes are tested in software to see if they can meet functional requirements.

Part of the process is “latticizing,” or deconstructing an item into a matrix that can be analyzed at a fine level of detail to look for things like weight distribution and stress points. Products like Dassault’s Simulia simulation software can simulate test conditions that not long ago required physical prototypes. Design becomes an iterative process in which the designer “defines loads, defines targets and constraints and then generates design concepts,” Fort said. “Over the course of the simulation, you continually test against limits.”

Less is more

In the case of the support truss, the iterative design and simulation process led to a new design that uses half as much material, has fewer attachment points and takes up less space. An angular shape of the old truss is replaced by smooth curves that distribute weight more evenly. The new design is cheaper, more efficient and has a “buy-to-fly ratio” – or the ratio between the raw material used for a component and the weight of the component itself – of 1.5, compared to more than 30 in the original design (see graphic below).

Software is also making the manufacturing process more efficient. Enhancements that Dassault will begin delivering next month make it possible for 3-D printed products to be tested in software before printing. Such testing is necessary because the additive process introduces certain variables that can affect product performance. For example, the continuous layering of heated composites, which are subsequently cooled, can cause weaknesses or distortions.

This simulated testing ability will make it easier for manufacturers to construct the equivalent of assembly lines for additive manufacturing, which will dramatically bring down costs and boost productivity. “We can now create composites in days for hundreds of dollars instead of thousands of dollars,” said Richardson. Three-dimensional printers can also be incorporated into existing assembly lines to produce customized parts on demand.

Which all adds up to a revolution in the making.

Photo by Paul Gillin

Illustration courtesy James Fort