Object of desire

Posted on 7 Mar 2011 by The Manufacturer

Computing horsepower and a manufacturing recovery are transforming the market for rapid prototyping, says Malcolm Wheatley. Despite competition from virtual prototyping, rapid prototypers see the manufacture of real parts as the big prize.

Jaguar Land Rover has had a sparkling year on the back of surging sales in Asia and a strong recovery in North America and the UK.

China, it transpires, is now the company’s third-largest market. Land Rover sales in China are up 1000% on 2005, and 111% on 2009 — an outstanding performance given the stresses and strains in the global economy over the period.

Sales in China are amply reflected in the company’s bottom line. Figures released in mid-February show that it made record net profits of £734m in first nine months of the financial year. Profits of £1bn, in short, look assured for the full year.

Underpinning all this is far more than just increasing manufacturing volumes. New products, and existing products customised for the needs of new markets, have each played a part. And in the dog-eat-dog global automotive market, the pressure on timescale is unrelenting. So it’s no surprise to discover the importance that the business places on rapid prototyping technologies.

“Rapid prototyping is a key enabler for product development at Jaguar Land Rover,” says Mark Barrington, manager of the company’s product development manufacturing department. “We use it extensively to support our product development processes, with the majority of the rapid prototyping parts that we produce going directly into prototype vehicle builds.” And propelled by economic recovery and a strong demand for exports, the growth story at Jaguar Land Rover is being played out right across British manufacturing industry.

In turn, this is underpinning the growing demand for the rapid prototyping solutions required for businesses to nimbly exploit the opportunities open to them. These days, traditional product development and prototyping solutions are too slow and too expensive.

So what rapid prototyping solutions are available? What technologies underpin them? Do the advanced CAD and PLM markets provide digital alternatives to physical prototypes? And, most importantly, how are manufacturers benefiting from the various options on offer?

Virtual vs. physical

Look closely at the big picture, and two distinct trends can be identified.

First, rapid prototyping technologies themselves are becoming ever more accessible in terms of affordability and capability. And second — and not without irony — advances in computer simulation technology are at the same time working to reduce the need for rapid prototyping — at least in terms of physical prototyping, as opposed to ‘virtual’ prototypes.

Indeed, says Kevin Ison, European managing director at CAD vendor Autodesk, the point is fast arriving when the physical prototyping of some parts will become obsolete.

“The ability to perform high quality 3D visualisation has progressed enormously over the past two years,” he says. “You no longer need a server farm to do it. And the more that companies see that they can readily tap the computing horsepower of the cloud, the faster they’ll move to virtual prototyping.” Bruce Klimpke, technical director at Integrated Engineering Software agrees, pointing to recent advances in computer horsepower. “There has been a huge move from 2D simulation towards 3D simulation,” he says. “How can you cut out weight? How can you substitute a cheaper material for a more expensive one? The more you can do multiple 3D ‘what if’ scenarios in an acceptable timescale in order to answer such questions, the fewer physical prototypes you need.” Take the Yoomi, a fast-selling combined baby bottle and milk warmer. This product was originally developed by fluid dynamics simulation consultancy Intelligent Fluid Solutions based on founder Jim Shaikh’s frustrations with feeding his newborn son.

Exploiting heat given off by sodium acetate trihydrate as it changes phase, the challenge was to take fresh milk from 5°C to 34°C within one minute of activation across a full range of baby drinking speeds.

But the initial prototype heated milk to only 17°C, he explains — half the needed temperature. Using fluid dynamics software from Ansys helped close the gap, resulting in a requirement for only four physical prototypes, just a quarter of the number that had originally been estimated.

“We were able to get the product to market two years ahead of schedule, saving £34,000 in prototypes,” says Mr Shaikh, who now devotes his time almost exclusively to the Yoomi business, for which there is strong demand from big retailers John Lewis, Boots and Mothercare.

Nor is the Yoomi example an isolated one, insists sales director at Ansys, Gary Panes.

“Advances in computing horsepower are a game changer,” he says. “You can do far more ‘what if’ simulations than ever before, and throw raw computing power at problems in a way that has not proved possible before. You’re building one virtual model, and then just throwing computer time at it.” For manufacturers, then, the message is clear: With today’s digital prototyping and simulation technology, fewer physical prototypes are required.

And when they are required, they are available more quickly and cheaply than ever before.

And physical prototypes are more accurate, too.

At Jaguar Land Rover, explains Mr Barrington, prototypes used to be made by skilled craftsmen who would interpret 2D drawings and manufacture the parts in question.

“We received their interpretation of what was required. Now we get exactly what’s shown, in 3D, on the CAD screen,” he says.

Horses for courses – which technology for you?

How those rapid prototypes are produced, though, can vary. While ‘3D printing’ — or additive layer manufacturing, to give it its more formal name — is to some people by now virtually synonymous with rapid prototyping, it is not the only game in town.

In fact, there are no fewer than three underlying mainstream technologies: stereolithography (SLA), selective laser sintering (SLS), and fused deposition modelling (FDM), the latter being yet another name for 3D printing.

Each technology produces prototypes with different characteristics and material properties.

Sintering, for example, fuses plastic particles together, while 3D FDM printing builds up parts by laying down successive layers of thermoplastic. The resulting prototypes aren’t true prototypes of the final part — they’re made from plastic rather than steel or alloy, for instance — but they are physical copies that for many design and test purposes are good enough.

Or, indeed, better than the final part. Ian Halliday, chief executive at rapid prototyping specialist 3T for instance, says that not only are parts produced through rapid prototyping technology often of a higher inherent quality than those produced through regular production technology, but they are also inherently more cost efficient. Rather than painstakingly removing metal from a billet, for instance, you’re only applying material that you want to be present.

“Time-to-market and cost are vital factors in the design process, and both are aspects that 3D printing can significantly affect,” adds Andy Middleton, general manager at Objet Geometries, whose 3D printing technology is in use at Jaguar Land Rover. “Multiple design iterations can be produced in quick succession, or even in the same build.” And plunging 3D printer prices — devices that cost £200,000 or so 10-years ago cost £20,000 or less today — are increasingly causing a blurring of the boundary between prototyping and real production.

This is one reason why rapid prototyping technology providers are so sanguine about the rise of virtual prototyping via 3D CAD and simulation as a potential threat. The allure of the mainstream manufacturing market itself is vastly larger.

“It’s a question of appropriateness,” says Tim Heller, European managing director of rapid prototyping vendor Stratasys. “You can do more virtual simulation than ever before — but people trust physical testing. And every year, more and more of them come to realise that they could use the rapid prototype part for actual manufacturing.”

Tooling gets the rapid treatment

Other approaches to rapid prototyping — some new, some old — are also gaining favour.

Specialist polymer bearing manufacturer Igus, for instance, now offers customers a rapid prototyping service based not on the bearing material that is used, but the tooling material. Its bearings — manufactured from its own proprietary iglidur materials — can be produced much faster from conventional injection moulding machines if the tooling to produce them is made from aluminium, which can be machined much faster.

Instead of tooling taking from six to eight weeks to produce, says Igus director of bearings Matt Aldridge, tooling can be produced in anything from one day to 15 days, depending on how much the customer is willing to pay. At which point the parts in question can be produced, from the same machinery and the same materials as production parts.

“All we need is a 3D file of the object that the customer wants to produce — we do the rest,” says Aldridge.

Imaginatively, too, some manufacturers are combining rapid prototyping with reverse engineering to bypass the need for a prior digital design, as at Formula 3 racing team Carlin Motorsports. Here, as with other F3 teams, the intellectual property rights for each car’s rolling vehicle chassis remains with its supplier, Italian specialist Dallara.

Rather than hand craft the vehicle parts that the competition’s rules allow teams to design and modify — front and rear wings, for instance — the Carlin team uses cloud point data to construct a virtual model of the whole car within PTC’s Pro/ ENGINEER’s reverse engineering module, and then “fits” each part digitally before conducting wind tunnel tests on a one-third scale model.

“It has definitely contributed to our racing performance,” says David Brown, chief designer at Carlin Motorsports. “Plus, we have a better understanding of our car and its performance.” Which, come to think about it, is what rapid prototyping should be all about.