Mixing tradition with the latest technology

One of the issues facing vacuum cleaner manufacturer Dyson is how to create increasingly sophisticated products such as its new DC15 ball vacuum cleaner, which has more components than its predecessors, while ensuring that design and development cycle times remain under control. Since 1998, Dyson has been using UGS' 'NX' digital product development software. Five seats were purchased back then but this figure has now increased to 88 licenses, with the software now being used by more than 100 R&D staff. This user group consists of design engineers, who are part of the product development team, responsible for generating ideas and new concepts; scientists who test and develop ideas and technologies; and the engineers who are responsible for the actual detailed design of the vacuum cleaners. As the early ideas and concepts for the DC15 began to come together, in the form of cardboard and foam models, design engineers used NX to produce detailed 3D models that helped them clarify their thoughts and refine the ball mechanism. John Myers, CAD systems manager at Dyson commented: "Our conceptual designs are produced in 3D, which has fantastic benefits. Rather than just producing views of the product, you design the real thing. This reduces ambiguity and often makes it easier to understand complex assemblies. You get a lot of feedback, seeing it coming together before your very eyes." The modelling features within NX enabled Dyson design engineers to work very quickly. "With the 2D CAD software that we used before, a design engineer could spend weeks on the design of a complex part. With NX, we can produce a 3D model in a fraction of the time," enthused Myers. The next phase in the DC15's development involved the creation of physical prototypes to help the design team better evaluate the new concept. Designs created in NX were used directly for rapid prototyping. NX geometry was converted into STL files that were then used by Dyson's in-house prototyping machine, which created prototypes from successive layers of powdered nylon. This process was made possible by NX's integrated NC machining software, part of NX's computer-aided manufacturing (CAM) portfolio. NX Machining used the 3D geometry to drive milling and cutting tools. Refinements made to the design were automatically incorporated into the CNC programmes, without the need for reprogramming. This meant costly delays from creating successive prototypes was avoided. "With a complex project such as the DC15 that required us to evaluate a number of alternative models, NX's ability to support rapid prototyping was an important factor in helping us to keep the development time in check," stated Myers. Peter Gammack, new product development director at Dyson told Eureka: "The philosophy at Dyson is rather traditional I suppose, in that we believe in a very hands-on approach to design and development. We're very keen for engineers to produce a sketch or physical model of a part. We also produce lots of prototypes. We make one, test it then refine the design until we get the performance or results that we want. "We do still use CFD, FEA and other simulation tools to optimise the design, but we like to make something and physically test it. You can see and understand something much better by trying it, rather than simply relying on the numerical software. We use lots of new materials in our products and so we prefer to test physical prototypes. Even in concept design, we prefer to sketch by hand, on paper or in notebooks. Some sketching is done on the computer in 2D or 3D, but a lot is done by hand," said Gammack. He added that while computers are good for optimising and improving designs, a lot of discoveries at Dyson are made are from touching, feeling or testing a physical model, to verify the robustness, reliability and so on. "For one particular model of vacuum cleaner, we would expect to produce thousands of prototypes. A simple catch for example, might have up to 100 different design iterations. We try to maintain as much of this work in-house, but of course we also have to outsource a lot of the prototypes to third party suppliers," explained Gammack. "Rapid prototyping has also become a lot easier recently with selective laser sintering [SLS] technology. There are new SLS machines and materials. We can very easily make up very accurate, representative 3D models using SLS machines," he concluded.