Absorb what is useful, reject what is useless, add what is specifically your own.”  Bruce Lee



We like to figure out new things and to make progress. We don’t like passivity, because it’s kind a bad for the creative mind. This time we are coming with new post about CATIA rules. CATIA rules are not something new, there are here for a long time. So why this post now? The aim of this post is to show our way of writing them. We use powercopies a lot. Certainly a lot of them are connected with excel tables because of different version of the same part. This tables can cause a lot of problems with some checkers. Hence this is place where rules can be very good in our case. So we want to change this excel tables with rules. 

Change dimensions with the rule

Certainly you can find on the Google a lot of thing about CATIA rules, and also it’s not that hard to understand. Here are some references: Creating a Rule  and Knowledge Based Engineering PDF. Duo to this second reference we were enabled to create what we need. As a result we will demonstrate you what we did. Maybe you will need much more, but at least you can get some basic information.

Certainly during this implementation we figure that there is a lot of possibilities. 


On the pic u can see three rules, for part version, for activation and for color change. First one will change length, height, width and radius depending on version. 

From this rule you can see some basic, while you need some conduction to make it work. In our case it is part version. So when it is “1” it will set  value for other parameters. When you want to choose parameter you need to click on it in the tree. We tried just to write it like the text but it didn’t work. We will show it in the video anyway. So with this knowledge you can parameterize any kind of model without Excel table. That was our goal on the beginning. Finally let’s see some other CATIA rule possibilities.

Activity with the rule

Furthermore in the process of the parameterisation you also need to activate or deactivate some things in the model, like number of holes etc. For example one plate in shorter version has 3 holes for screws and in the bigger version four. So you need to activate that one or deactivate it. Certainly you can do it with the rule.

Of course with this approach you can activate or deactivate any element.

Color with the rule

Even more you can also change the color of the elements using CATIA rule. We found two ways to change color, first with name of the color and second with the hex code. 

So this is our implementation of CATIA rules. In a conclusion, from our experience part parametrisation is one of the best. We hope that we helped you with this topic.   

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