Learn computer-aided design, manufacturing with 'Catia'

By Zatni Arbi

JAKARTA (JP): Each time we hear the term computer-aided design mentioned, we'd immediately think of AutoCAD. Architects, interior designers and hordes of other engineers use AutoCAD in their work. In the world of computer-aided design, manufacturing and engineering (CADAM/CAE), however, Catia is the most widely used tool. Catia is a product of Dassault Systemes, a subsidiary of Dassault Aviation, the French aircraft maker. Big Blue is responsible for marketing the software product and providing support for its users.

When IBM announced the latest update, Catia 5.0, and offered me a short one-day tutorial, I was excited. I know this heavy- duty manufacturing design tool is used in a large number of manufacturing companies all over the world, including the Danish pump maker Grundfos, which I visited earlier this year, and our own national aircraft industry IPTN.

So, last week I found myself playing around with the US$17,000 software on a very powerful IntelliStation M Pro at IBM's office in the LandMark Building, Jakarta. IBM Indonesia has only one unit of this Pentium III 500 MHz-based workstation, so I could not take it home and toy around with it for two weeks as usual. They needed the powerful machine for their demo and training activities.

I was told earlier versions of Catia ran only on UNIX machines, and IBM's RS/6000 used to be the ideal platform. Today, the latest release can run on Windows 95, Windows 98 and Windows NT, and therefore a Wintel Workstation will do. Versions for the UNIX platforms are still available, of course. The requirements are quite high, though. I was also told that the graphics engine alone accounted for one third of the total price of the workstation, and no wonder the rendering was so fast. I was able to turn the wheel around without any jerky movement at all.

The use of the Windows platform also adds several benefits, like drag and drop, object linking and embedding (OLE) and the ability to open multiple documents at the same time. And, compared to Version 4.0 that was shown to me, the Windows-based Version 5.0 Release 2 looks much more familiar with all the icons and toolbars. The screen is well-organized, and most of the tools are hidden until you call them up. This helps make the formidable program less threatening.

Knowledgeware

All this time I had thought a CADAM/CAE wouldn't be so much different from graphics design software like CorelDRAW or Adobe Illustrator. That day, Hindra Salim, IBM's marketing specialist, and Nanang Ali Sutisna, their CAD/CAM/CAE specialist, led me step by step through the process of designing a bicycle gear, and they explained to me what made a CADAM/CAE application different.

First of all, every step of the design process is recorded. Whatever action is taken to produce the gear -- or the wheel of the car that you see in the accompanying picture -- is recorded in a tree form. Any change that we'd like to make later on to the so-called "part" can be made just by clicking on the appropriate branch of the process tree. So, for example, if I want to change the "edge filet" of an object, I can go to the process tree, look for the branch, click on it and use the pop-up menu or dialog box to change the "radius".

The good thing about the tree, which you can see on the left of the screen, is that I can also reverse-engineer the drawing of a part. I can trace back the design process by loading a part and going back one step at a time up the process tree. This can be a fast way of learning to design an object or its components.

However, the most powerful feature of the tool is perhaps its KnowledgeWare. Suppose I am designing a pair of high-precision forceps. I may not be aware that the manufacturer does not have a 1 mm chisel that it can use to create the object that I am designing. Therefore, when my design is ready, the manufacturer will have to reject it and return it to me for modification.

In Catia, the knowledge that there is no 1 mm chisel can be entered into the database so that when I create my design I will be warned if the specification does not conform to it. In other words, Catia will remind me that I can only use the 4 mm specification as the minimum.

Data can also be entered into the program's database prior to the design process so that I will not design an object made of a specific material with a thickness less than 2 cm, for example, because with such a thickness, it will become too brittle and will crack easily. This feature certainly helps me avoid errors very early in the process. Besides, other people can replicate my work very easily.

Another powerful feature of the program is its rules, which can also be seen in the accompanying screen shot. The wheel, for example, has five holes for the bolts that secure it to the car's axle. We can add a rule that will automatically reduce the number of holes to four if the diameter of the entire wheel is reduced below 26 inches, for example.

Two Platforms

One thing is obvious. A one-day hands-on training session may not make us a proficient Catia user, but it's enough to give a novice like me a feel of the breadth of its functionality.

Because CADAM/CAE requirements are not the same among all customers, Catia is offered in two different platforms, P1 and P2. The choice of the word "platform" is rather misleading here, as it actually refers to the configuration of the package that have been targeted to two different levels of needs.

P1, for instance, has been targeted at small and medium process-oriented companies. With scaled down functions, it helps users in solid modeling tasks in the already familiar Windows environment. P2, on the other hand, consists of products based on a hybrid modeling technology. It provides expanded digital products, process and resource definitions plus review functions that can operate on complex projects.

With an advanced 3D graphic user interface, P2 is an environment for knowledge-driven design and full-scale digital mock-up (DMU). The one I used in the one-day tutorial was the P2 of Version 5, Release 2. Release 3 was announced last month.

Incidentally, take a look at the latest models of Samsonite suitcases, and you may be impressed by the precision of the parts that allow the manufacturer to use lighter materials without sacrificing strength. Like a lot of cars, trains and airplanes, Samsonite suitcases are designed with the help of Catia. If you're into mechanical design, engineering and drafting, this is a software product that you may want to get familiar with.