Supercharged CAD/CAM comes to Cosworth Technology

Cosworth Technology, the Engineering, Castings and Manufacturing Divisions of what was Cosworth before the Audi acquisition in 1998 – those responsible for designing and building performance engines for production cars – says it has solved all its CAD translation problems following the installation of CADfix in June last year. It’s a convincing story, not least because they weren’t trivial. Cosworth is not just a high performance engine builder. Yes its recent developments include elite engines like the Aston Martin V12, Audi RS4 and Ford SVT Focus, but it’s also a complete powertrain provider. As Mike Robson, Cosworth Northampton’s principal CAE systems engineer, says: "Car manufacturers come to us with a particular requirement and we will do as much or as little as they need." Projects, he says, range from a single cylinder head to a V12 engine, "and most configurations in between". So to offer this kind of consultancy across the broad spread of automotive manufacturers, Cosworth has to be able to accept geometry from a wide range of CAD/CAM systems. And indeed it has licences for the major solid modelling solutions – Pro/Engineer, Catia, CADDS5, Ideas and UGS. Tough translations So data import was rarely a problem: the issue was translation between them, and on out to third party analysis packages. As Robson explains: "It’s horses for courses. We recognise that different modellers are particularly well suited for different engineering tasks. We might use Pro/Engineer for a cylinder head design or Catia for a complete engine assembly, for instance. Added to this is the need for our FEA (finite element analysis) team to translate into a whole raft of different formats for meshing. So it’s vital we’re able to switch between modelling environments." This was the sticking point. Different systems have different ways of defining 3D geometry internally, and even ‘neutral’ formats like IGES aren’t always adequate: differences in tolerance between ‘reading’ and ‘writing’ applications can result in the former introducing gaps where the latter had merely neighbouring surfaces. Until last year, Cosworth did its best with stand-alone translators, and regularly still found translation errors. "We were probably able to convert 65—70% of the data sets with no errors," says Robson. "We recognise that there are always going to be some stubborn files, but we felt that anything below 95% would not be living up to our standards and expectations." Then the firm discovered CADfix, a suite of automated tools and an intermediary environment developed by Cambridge-based FEGS to deal with 3D interoperability issues between CAD applications and downstream tools like FEA, or between different modellers. It wasn’t overnight, but it was close. Says Robson, "We had one problem where had to convert a cylinder head from Pro/Engineer. We’d been working on this for a number of hours. We were able to achieve a fully surfaced model, but not what we really needed, a fully defined solid body." Within three days of installing CADfix the problem was solved. "It was a revelation," he says. "Without any training at all we imported a Pro/E model into CADfix, resolved the geometry into a coherent solid and exported the data into a format that would read smoothly into the other CAD systems." So good was it that CADfix is now used as the data hub for all projects requiring multiple CAD systems. Robson says it’s saved many, many hours against the old resource-intensive data conversions, and cut lead times. And it means that translations to other CAM (computer aided manufacturing) packages can be done in a matter of minutes. "We’re not having to worry about translation between packages just to do another task," says Robson. "When you get the translation it’s accurate; nothing’s been dropped off and we can control it fully." Now CADfix is also being used by Cosworth’s analysis department. With the firm’s consultancy having expanded to everything from emissions to driveability, and fuel consumption to engine diagnostics – and a range of solver applications in use to support that – Robson says: "They have found CADfix’s de-featuring capabilities particularly helpful – so helpful, in fact, that we have invested in more licences."