absolute axis system

[mehdiy]

hello
I have a problem about axis system in catia .
Can you tell me ..what is the absolute axis system and when we use this feature?
best regard

 

[catiajim]

What version of CATIA? I assume you mean V5, as it's a pretty simple matter in V4.

V5 uses the axis system of the first part in an assembly as the "absolute" axis sytem of the assembly.

V5 has pointed out the fact that, in a Part Based Design world (i.e. V5, V4 with VPM, etc), there is no such thing as Absolute Coordinates. All Coordinates are relative to the Assembly Context you are in.

In the Aircraft world, we use "Aircraft Coordinates" to refer to things. In V4 when we had multiple parts in a single model, we demanded that everything be built in Aircraft Coordinates. When we move to V4 with VPM, and only had a single part per model, we still insisted upon "Aircraft Coordinates", however it became rapidly appearant that this was all relative based upon which assemly within the aircraft you were talking about. When we started using Configuration Management in VPM, it suddenly became important to know what serial number aircraft you were on as well.

In the V5 world, it is so easy (an desirable) to move parts around that the entire concept of "Aircraft Coordinates" is being laid to rest (although it is not dying peacefully). The only time that it becomes important is when you are actually in the aircraft assembly!