Цифровая платформа по разработке и применению цифровых двойников CML-Bench®
Уникальный онлайн-курс «Цифровые двойники изделий»
CAD/CAE/CFD/CAO/HPC новости 26 Октября 2004 года
Данная новость была прочитана 4579 раз

CADfix 6.0 новая версия популярного CAD транслятора

FROM ITS DAYS as FEGS, TranscenData has become one of the leading providers of vendor-neutral data translation software, primarily through the development and sale of its CADfix application. Since its initial release, CADfix has provided many users with the tools needed to successfully move 3D data from one generating system to another. Unlike other developers, Transcendata has shied away from the use of bespoke point-to-point translations for CADfix, instead concentrating on providing a data exchange hub with a set of translation tools that interface to all common systems and formats – and it’s this that has set the company apart from its competition.

Whereas other software products concentrate on simply moving data from one discrete system to another, CADfix does much more by providing a massive range of tools which are geared towards taking a 3D CAD file exported from one system, analysing and repairing it, then outputting it in a format which can be successfully read by the chosen receiving system (or systems).This provides many advantages, not the least of which is the ability to work with many different vendors’ applications, rather then purchasing bespoke, bi-directional translation systems. In more recent releases, there has been a lot of work done on extending the format support beyond the neutral, to the point at present in which the system can handle and output most proprietary formats.

In the past, if there was one issue with the system it was that while CADfix could handle almost every problem you threw at it (including some very dodgy data indeed), it was obvious that the system had been developed from a technical perspective, with the emphasis on functionality and less attention paid to the ease of use and automation of the process. In response to this, much of the major development done for CADfix release 6.0 is to make the data repair and translation process more effective, easy-to-use and more automated. So let’s take a look at how things stand now.

General updates

There have also been several general updates to CADfix in the months since the last release. While we’ll be getting onto the user interface and workflow redesign shortly, it’s also worth noting that the system now includes Undo/Redo (within user-specified limits. i.e. number of operations), which will be very handy for checking the success of different operations.Work has also been done on providing Area and Mass properties inspection tools, which in addition to the obvious benefits, will also make it easier to validate volumes and properties of processed models (to ensure that the volume remains the same). In terms of graphics display, in previous releases you had to switch on the dynamic view manipulation tools, whereas from V6 onwards, you’ll have them always on automatically.Another update I really like is that you can customize exactly how you go about interacting with the model geometry (in terms of keyboard and mouse settings). It might sound a little trivial, but this means that you can set-up the system to mimic your workhorse CAD system – which for casual CADfix users, means that they don’t have that re-adjustment period when picking up the system after a time of non-use.The last change is similarly small, but very important to some users. CADfix has traditionally used red and green to indicate the connectivity state of edges within a model. While this isn’t an issue for the vast majority, it can be problematic for those with red/green colour blindness – so you can now customise colours if needs be. Elsewhere, in terms of functional updates, the probe tool has been made much more interactive and model window-driven, which means you don’t have to go hunting through menus to inspect specific areas of your model.

Workflow and UI

While previous versions of CADfix provided access to its functionality through a wide range of complex dialogs, pop-up boxes and menus, CADfix 6.0 sees a major redesign of the user interface combined with radical reinvention of the system’s workflow. The interface is now much cleaner, with a large proportion of the process being driven through the left-hand panel. To start the data repair and translation process, you simply select three things: 1) the part file you’re working with; 2) the target system for which it’s intended (see the box to the right for details of both) and 3) whether or not you want to run quality checks on the resultant part - but more on that a little later. The system then automatically works through four major steps: Import, Repair, Prepare and Export.

IMPORT: CADfix’s data import capability is as you would expect, including all manner of formats; standard ones such as IGES, STEP (AP203, AP214), VDAFS, STL, kernel native files from both ACIS and Parasolid, and proprietary systems with Catia, Pro/E (using Granite One), Cadds 5, DXF/DWG and Ansys.

REPAIR: During the Repair stage each model’s topology is checked to ensure its validity. Under the hood, the system scans through the data looking for bad or missing entities, creates a results set and fixes any problems. In specifics, the system includes checks (and repairs) to merge points and edges, fix intersecting edges, trim up untrimmed surfaces, remove unwanted data (such as duplicate entities) and build in missing faces and solids. Once you have a valid model, it moves onto the Prepare stage.

PREPARE: At this stage the model is readied for the target system to ensure that it can be imported without too many problems, by adjusting specific attributes and factors. In specifics, the flavouring checks include simplification of surfaces to primitive forms, reducing surface complexity (order), fixing bad NURBS parameterisations, replace twisted and folded surfaces, healing edge-surface deviations and removing small features. It is here where CADfix really pays dividends, because although these sorts of problems can often be overcome by having expert knowledge in the two systems you’re moving data between, that information is often very hard to come by. Here, it’s formalised into an automated tool.

EXPORT: Having successfully repaired and prepared the model is now exported to the required format. Most export formats have a few options available for fine tuning. There’s also the possibility of a final check on the model geometry with CADfix able to access proprietary geometry and body checkers during export to Parasolid,ACIS and Pro/E if required.

However, CADfix is not just about translating and fixing. There's a new option in version 6.0 that allows the user to perform a product data quality (PDQ) check of an imported CAD model. The PDQ analysis is fully configurable, with tests selected from the CADfix library and tolerances set as required, to enable users to test for conformance to in-house policies and align their data with international PDQ standards as laid down by organisations such as SASIG,VDA and JAMA. Once a PDQ standard has been selected, CADfix will scan the model and present the resulting PDQ failures to the user both graphically and in a report file. This can be used as a final check before sending data back to a customer or as the basis for further diagnostic driven repair work.

Knife and fork

Although I’ve said the system is based on four steps, most users may never be exposed to them, and the actual manual work should be reduced to a minimum through the automation that the developers have done for CADfix 6.0.The new Wizard pushes the geometry through the process and will output the required format file in a fully repaired state, only really asking the user for input when a problem needs attention.

A typical example of this is when the CAD model being translated contains a serious problem such as a completely missing face that may cause the automatic repair to fail.The CADfix Wizard process switches into a Diagnostics mode and automatically scans the model to determine the remaining issues with the data. CADfix includes over 100 different checks on the geometry and should spot almost any possible error within a model, ranging from major problems such as missing surfaces/faces, or duplicate surfaces, through to more detailed errors such as edge-surface deviations.

The system presents you with a summary of the problems encountered (which are colour-coded for severity) and a list of possible resolution methods that could be used to repair the problem. Each of these contain hyperlinks to supporting information that explains the problems further. The user can then select and try the different resolution methods to achieve the most appropriate fix. The CADfix Diagnostic system automatically re-scans the model as the users completes the repair work, and will revert back to the automatic Wizard processing at the first possible opportunity.

In addition to the automatic Wizard and Diagnostics tools, there is another set of manual tools that can be used to further refine the data export results or to conduct quite specific operations. These include commonly used functions such as ‘Delete’ for deleting unwanted entities, ‘Replace’ for manually replacing badly defined edges and surfaces with new entities, and ‘Build’, the Geometry Builder tools that allow the user to create new geometry and topology entities. Also included here are the tools used for more advanced downstream application specific tasks such as entity Collapse, Join and Split.

Processing for downstream

While CADfix’s primary use within industry at present is the repair of geometry for translation purposes, it also has a long history in the FEA market as a tool for preparing CAD geometry for Finite Element Analysis. The benefit to those not currently using FEA is that these same tools are also applicable to many other downstream processes, so let’s take a look at what it can do. Much of this functionality is geared towards de-featuring, which for those unfamiliar with the term, describes the process that many FEA users go through to repurpose a complex CAD model for analysis. This typically means removing small features which have no effect on the structural integrity of a part (such as small holes, fillets etc) but that have a major impact on meshability. CADfix addresses these downstream issues by providing tools for collapsing short edges and small faces, joining chains of edges and regions of small faces, finding and removing unwanted holes and protrusions, and splitting regions that might otherwise prove troublesome to mesh.

Moving away from structural FEA and more into the realms of the Fluid Dynamics, CADfix 6 see the introduction of some functionality which will make the generation of the internal flow volumes much less painful, as the system can now automatically create complex solids from the voids within a CAD model, such as the oilways in a cylinder head or internal flows within a manifold. In terms of export for such applications, these flow volumes can be isolated and exported to any of the supported CAD formats, including STL files, which can also be output to a neutral mesh or a Nastran-specific mesh format.

CADfix handles the vast majority of problems you could come across and the advantage is that it will now allow you to handle everyday problems quickly and efficiently using the wizard-based approach, while reserving the use of the more manual, interactive tools for those occasions when you need to dig and manually rework geometry.

In conclusion

I’ve said it before and it still holds true, with all the advances and innovation within the 3D product model sector, I find it amazing that the industry as a whole still can’t get its act together and work out the data translation problems that plague many users’ lives on a weekly, if not daily, basis. The problems, I suspect, primarily revolve around a reluctance to work together to improve the exchange and portability of data, but also the mathematical base on which all these systems are built – as it’s these mismatches in tolerance that can really cause headaches during the translation process. But thankfully, there are developers like TranscenData out there working to make the process much less painful – which CADfix undoubtedly does.

The new release shows that the developers of CADfix have listened to its growing user base and reworked some of the less user friendly and complex aspects of the system to streamline the import, repair and export workflow, to the point it’s at now, where the needs of both the regular expert user and the casual user are met. But more importantly than that, the system has become a solution to a number of industry needs, outside of its traditional sphere of influence, which means that users (both new and existing) can get more benefit from adopting the product.


Written by: Al Dean.  http://www.cadserver.co.uk