Rapid manufacturing set to go mainstream

Developments in rapid manufacturing technologies – and designing to take full advantage of these – are set to bring about a revolution in design and manufacturing. Customisation will become the norm, rather than the exception, and more and more products will be made locally or even in the home over the next decade. Price mark-ups of the first manufactured products to get to market are, in some cases, 10 to one, and market demand is now beginning to drive the technology. Rapid production of more and more consumer and medical products at lowering costs is gathering pace – and, in time, this may even embrace replacement human body parts. These were the messages to emerge from the ‘Manufacturing Reinvented’ seminar at London’s Royal College of Art, which made it clear that rapid manufacturing of consumer products is already upon us. Upmarket lighting and furniture, dental implants, braces and false teeth, jewellery, and customised ear plugs and hearing aids are already being produced by additive methods derived from computer scans and models, often at large cost mark-ups. While most of the early adopters, according to Dr Phil Reeves, managing director of Econolyst, are based around people, this has not been exclusively so. There has also been the rapid manufacturing of aluminium heat sinks for use in a helicopter, for example, as Dr Chris Sutcliffe from the University of Liverpool, pointed out. And the technology also extends to the creation of certain parts used in motor sport and some top end cars as well. “The biggest challenge to rapid manufacturing is the production of full scale, verified and useful manufactured parts over a wide range of applications,” states Sutcliffe. “The majority of manufacturing machines are very expensive, very slow, very difficult to use, are maintained by their suppliers at high annual cost – and it probably won’t be very long before your machine is obsolete. There are many process variables that are not yet fully understood and the metal powders are mostly hazardous to work with.” According to Professor Richard Hague, the barriers to even wider adoption are a lack of repeatability by existing systems and the need to change the culture of organisations to accept new technology. “Improved design software is also required to maximise the design potential of products the systems are able to make,” he says. Hague is the head of the rapid manufacturing research group at the University of Loughborough. This is engaged in a project to develop tailored injury prevention and performance improvement for protective sports garments (Scuta). While it is fairly easy to scan in a human body shape and produce a rigid moulding to fit, there is a need to make it in the form of connected panels to give it flexibility, without compromising its protective properties. So body surfaces need to be meshed, but in a different way to that used for finite element modelling. Mixing up the medicine Meanwhile, the solution to the lack of cheap machines is to make your own, argued Dr Adrian Bowyer of the University of Bath. He has for some time been pushing forward a project called RepRap (www.reprap.org), in which the majority of parts for a design of a fused deposition modelling machine, called Darwin, are themselves made by FDM, so one machine can be used to make more machines. “It still needs nuts and bolts, and electric motors,” says Bowyer. “Things that have to be added in have to be widely available and very cheap.” The motors cost £1.50 each and the Cartesian robot to support the write head requires M8 studding and a couple of sheets of MDF. It also uses microcontrollers connected on a token ring and programmed in ‘C’. The development cost of the project was £20,000, plus the cost of supporting a PhD student, and the target cost of all raw materials, motors and chips is £250. The print head currently uses polycaprolactone, but that may soon change. “We want to switch to polylactic acid, which can be made by fermenting starch,” he said – and showed an example of such a part produced by one of the machines in New Zealand. Professor Julian Vincent, also from the University of Bath, pointed out that biologically derived materials can be very strong indeed – or have their mechanical properties tailored to end use. Biological polymers are based on either proteins – such as spider silk, which can be stronger than Kevlar and highly energy absorbing – or on polysaccharides, exemplified by chitin, which, he claims, “competes with carbon fibre”. Before industry can rapid-manufacture in spider silk, though, there are a few more things to learn. Nonetheless, the path to the future is clear. Take, for instance, Janne Kytannen’s Netherlands-based business Freedom of Creation. Once, it was largely dependent on government support for what were mainly research projects. Now, it is strictly commercial, producing designer lighting, furniture, jewellery, handbags and packaging. In terms of time to market, Kytannen says he completes most of his design projects in a single day and, on one occasion, completed a design on his laptop while travelling in a taxi from New York’s JFK Airport. After receiving the customer’s approval, he had parts delivered to clients five days later. Products can even be manufactured inside their own packaging, he adds. Additive rapid manufacturing is the first major challenger to the three traditional ways of making things that have been used since ancient times, says consultant Geoff Hollington. Those processes are ‘subtractive’ (carving material away, as in flint tool making and modern machining), ‘moulding’ (pottery, casting and plastic moulding) and ‘forming’ (bending, forging and stamping). “Maybe we have to turn to a new kind of mechanical design,” he says, citing the ‘Octo arm’, a pneumatically operated elephant trunk type grasping actuator, as being ideal to manufacture by rapid manufacturing. At the seminar, Hollington spoke about “life without motors, shafts or gears” and offered a glimpse into the future: a pen with ink inside a fluid muscle type envelope, with the rest of the pen built up around it; and of modular loud speaker units, from which large systems could be built up, and a single speaker with acoustic spikes inside that could not be made by conventional manufacturing methods. He also identified the year 2000, when rapid prototyping started to be supplanted by the first rapid manufacturing, as “the year when we began to lose our bearings”. This was topped by Reeves and Sutcliffe – who foresee the printing of human cells to make new body parts. Sutcliffe regards the printing of biological materials as being potentially of much greater value than printing consumer products. It was generally agreed that, when the fundamental patents underlying most of the current rapid prototyping and manufacturing technologies ran out, a drastic cut in the cost of machines is likely. As Geoff Hollington pointed out: “We are where the Industrial Revolution was in about 1800.” Pointers * Rapid prototyping is presently being supplanted by additive rapid manufacturing * The fastest growing, most profitable areas are currently in the production of products, both medical and consumer, that are matched to fit the various parts of the human body * There is strong market pressure to improve the performance/price ratio of rapid manufacturing machinery. Within a few years, they could cost hundreds of pounds each, a vast reduction on today’s prices