Solid Edge designs in flexibility

Tom Shelley reports on a step forward in CAD.

Solid Edge ST3 (the 'ST' standing for 'Synchronous Technology'), allows users to move between what is called 'Ordered' designing, where step-by-step operations are maintained in a feature tree and the Siemens PLM 'Synchronous' approach, which does not. The same model can have ordered and synchronous branches, but once one moves out of the ordered environment, by taking hold of features and moving them about – there is no switch to change from working in one way to working in the other - it is not possible to put them back into an ordered form. "For some approaches", says Solid Edge's Russell Brook, "ordered is better than synchronous, but for others, it isn't." To make design changes to a model produced by somebody else, the traditional approach requires identifying the appropriate point in the feature tree and go back there to make the modification, which then ripples through to the final model, hopefully changing it in the right way. This is usually complicated by the fact that no two modellers produce geometry in exactly the same way, so it is not always obvious to the person making the modification, how the original designer produced the model. If the geometry is very complicated, such as in, for example, an engine block, there may be instances where the design process as stored in the feature tree is so difficult to unravel that it is quicker and easier to create the whole model again from scratch, whereas the synchronous technology allows quite major changes to be made with a few mouse clicks. On the other hand, holes and surfaces are best handled in an ordered manner, and the software will not allow them to be processed in the synchronous environment. In demonstration, surfaces were generated by creating a Bezier curve and an arc, joining them at a point represented by a blue dot. The dot and points on curves used to create the surface could be moved around, but the surfaces are not completely free form. Solid Edge is primarily a tool for mechanical engineering, not conceptual industrial design, a role intended to be fulfilled by the other Siemens PLM product, NX. Brook says that the latest enhancements are also being rolled out in NX, but by a separate team of developers, so it is, "Not always implemented in the same way". Other enhancements in ST3 include improvements in sheet metal, piping and frame management, assembly management and drafting. Added features in sheet metal include new closed corner types, etching of part numbers and other geometry, and tabs added for production or transport purposes. In drafting, all manufacturing dimensions and annotation, including item numbers can be embedded in the assembly, and multi-cultural drawings allow mixing of character sets from multiple languages on a single drawing or in a single annotation. Prominent during the demonstrations was a new customisable radial menu, and the Insight data management and collaboration tool now takes full advantage of Microsoft SharePoint 2010. Simulation, which was added in ST2, is based on Femap, and uses the same underlying NASTRAN technology as full Femap. The ST3 version includes new torque and bearing loads, user defined constraints and new ways to connect assemblies such as bolt and sheet metal edge connectors.