2D or 3D?

7 mins read

'Collaborative engineering' is the CAD marketeers' mantra of the moment – at a time when many, especially smaller, manufacturers still haven't moved form 2D to 3D yet. But John Dwyer finds that new look 'design chains' are forcing all sorts of change – and resulting in real benefits.

It’s hardly news that IT suppliers are well ahead of their users. But the gap is probably at its widest in product-design technology. And the word on the street is that it’s getting wider. Nick Ballard, who follows the CAD (computer-aided design) and PDM (product data management) markets at UK industrial analyst Cambashi, told delegates to its recent seminar near Cambridge that there are still plenty of new CAD users – small companies moving from drawing boards to 2D CAD, or from 2D to 3D. The vendors, however, are banging on about ‘collaborative design’ and the Internet, talk which many small users find “frightening”. Ballard says the leading vendors – PTC, IBM/Dassault, SDRC and UGS (formerly Unigraphics Solutions) – may have a collaborative-design strategy for the likes of Ford, GM and Boeing, but none of them has worked out how to make collaboration appeal to smaller accounts. He says there are, “significant advantages to be gained in reducing time scales in getting products to market. And that means getting to small companies and persuading them to play. There needs to be some joined-up sales and marketing from the vendors to increase that uptake [but] it’s become a dialogue of the deaf. People are selling to people who don’t think they have a need.” Companies are at very different stages of readiness to accept the messages the CAD, PDM or collaborative design people are giving them, says Ballard. The nature of the need for CAD tools is very different for companies at each stage of readiness, particularly among the SMEs. “One size does not fit all,” he continues, “and if joining up the design chain is to work it has to be implemented at the bottom as well, and that’s their biggest challenge. All the players are concentrating on top tiers. All of them have yet to work out how to bring down their technology into the bottom of this design chain.” UGS and Dassault would contest this, since they’re slugging it out on small shopfloors all over the UK. UGS’ SME-friendly offering is Solid Edge. Dassault’s equivalent is SolidWorks. And, of course, there’s always Autodesk. Ballard’s point, however, is about the gains to be made from collaborative design, which involves not just designers and the shopfloor in designs. It’s about involving ‘stakeholders’, who might be in sales and marketing, retail and maintenance people as well as customers themselves. Ballard says there are eight million geometry creators to sell to in the world market for design tools – but 30 times as many stakeholders who, if collaboration means anything, should have access to designs, even though that’s not their main work. The real non-hype world Small companies, however, have certain basic requirements before they even begin looking at collaboration. Fact is, many are still cautious about the decision to move from 2D to 3D – but they will increasingly find themselves drawn at least into this transition. And that may be for no grander reason than simply because their old system just doesn’t meet their needs any more. This was true, for example, for Herga Electric, which designs and manufactures switching and sensing systems. They include operating theatre footswitches, waterproof air switches for US Jacuzzis, remote switches operated by infrared sensors and pressure mats for industrial safety applications. Herga has to meet both IEC and US Underwriters’ Laboratory (UL) for flame retardancy, traceability and other standards. Footswitch volumes can be 10 a month, but it may need 10,000 air switches a week. Herga has sales of over £4 million and employs 160 in Bury St. Edmunds, Suffolk, including two mechanical and one electronic engineer for PCB design. It bought a Robocad 2D drafting system in 1991 but found the system limited and unstable – it locked up frequently – and Herga hadn’t taken a support contract. Eight years later Herga decided to replace it with a Windows-based 3D modeller. One model does all At the last count Herga had 3,000 live saleable items. Project and engineering co-ordinator Ian Thomas says the firm makes a huge number of variants – different colours, cable lengths or plugs – of four or five main product lines. So parametric design is a major cost saving here. Herga can now develop one solid model and produce the drawings for a specific version automatically by editing dimensions. Price mattered. Thomas says the company decided on UGS’ Solid Edge/Draft because it would move it from 2D to 3D in affordable steps. But just as important was that this choice allowed gradual change. Designers could carry on with familiar 2D design while getting used to work sharing from centrally held, networked files – and to a Windows-based system. Another pressure was that Herga was beginning to design for form as well as function: its products had begun to include complex curves difficult to describe accurately in a 2D drawing. And the move to 3D was also an important marketing step: shape and colour are becoming important in the design of footswitches used in expensive medical equipment, for example. Says Thomas: “We saw styling and design as a way to differentiate our product in the marketplace. We came up with something that really set us apart.” And he adds that even some years after the first versions the product is “still unique”. Customers can use in-house colours and shapes they are proud to present. And there we are: this now makes design collaborative, involving sales and marketing as well as design and production – and there are a number of other engineering staff who also contribute to Herga’s designs. “It’s a team-orientated approach. It involves people in marketing as well as in assembly, the tool room and so on,” says Thomas. Outside the design department, Herga still communicates design information internally and to suppliers and subcontractors in 2D. And it’s here that Thomas finds the biggest gap between reality and IT-industry marketing hype. All the information the assembly operators use is 2D, and many of them aren’t computer literate. The information has to be in an easily-assimilated form. Outside, “Being able to use 3D data has opened up the services on offer to us from a design point of view,” says Thomas. But there are still “age-old” translation problems moving design data around this community, especially in 2D. In particular, Herga finds that familiarity with computers among tool makers – who work in 2D – and prototyping companies varies from those who do all their work in pencil and deal in aperture cards, to profitable, well-funded companies keen to keep at the cutting edge of 3D work. The firm finds it simply has to deal with all of them, and Thomas believes the gap between hype and reality is growing wider as the leaders continue to forge ahead of the pencil brigade. It isn’t much help a toolmaker using a modern tool like email if what arrives – even via a translation agency – doesn’t convert error-free to something Herga can use. “We’ve had to lower our expectations,” Thomas says. “We expected more from the translation agencies, but it isn’t there.” Big step forward But 3D modelling is a big step forward even when most of the output is 2D. A key 2D limitation is lack of associativity – meaning that if a change is made in one view, it is not automatically reflected in all the other views. Even if a 2D system produces flawless drawings, each is a separate file. If, however, all drawings derive from one 3D model, changes to the model update all the drawings produced thereafter. All you have to watch for is out-of-date printouts. And unlike 2D systems, 3D-produced drawings can include a 3D view on the drawing sheet so that the shop floor can see what it’s being asked to make. “Working with an assembly you can see how changes interact with other parts of the assembly,” says Thomas. “When you change the 3D model, the 2D drawings change and you can see the changes that have been made.” If collaborators can sit at the same screen they can get round data translation, because easier visualisation (see panel) is another related 3D modelling plus. Thomas says Herga was modelling parts and modelling assemblies “within a month”. The installation ended the “hours of discussion” which used to go on between designer and drawing office about the way a product was supposed to look – “a major benefit” in design productivity. 3D at the cliff face Visualisation was important for DMM Engineering which, on the banks of Llyn Padarn near Llanberis, Wales, produces rock-climbing, mountaineering and industrial safety equipment. In 1996, DMM bought Wild Country, which held the original patents for camming units. Rock climbers use these devices to provide a frictional anchor in rock features where nothing else holds. The climber presses a trigger to contract an aluminum alloy cam, inserts the device in the rock, lets the trigger go and attaches his or her rope to the device. If they fall, the cams take their weight. DMM had to develop a new, product line to complement, not compete with Wild Country’s single-stem cams. Says technical managing director Fred Hall, the firm realised it would need 3D CAD to develop products based on hoop-stems. And DMM wanted the devices to look attractive and be lighter and stronger than anything produced before. DMM bought two SolidWorks seats from SolidBase. Using PhotoWorks photorealistic rendering software with SolidWorks, DMM developed a colour indexing system for the camming devices, colour-coded by size for climbers, and the software also provided graphics for promotional purposes. Hall adds that 3D visualisation provided by SolidWorks aided interactions between designers and manufacturing. As part of the design process they can think about such issues as longer tool life and faster cutting paths. Hall says the software has helped DMM reduce its design cycle for the new line by 50%. There was also a stakeholder benefit. Hall says a large part of the success of a product is the ability of the engineering department to sell the product to the sales department and retailers – the 3D graphics and stylised components provided by SolidWorks did this for them. Hall says that when DMM used AutoCAD’s 2D package, it relied on “time-consuming, limiting and expensive” prototypes. Now it can consider design options before committing. Product weight, inertia and stiffness can easily be adjusted. DMM could take away redundant material while producing a robust, long-lasting product. In the end, DMM found that sales orders for the new line during the first year were three times initial estimates, and take-up from retailers was the highest ever for a new product. Says Hall: “Either our market research was wrong or the product was right, and I know the product was right.”