time dependant features

[swmetal]

Hi all,
what are time dependant features? I've seen the list i.e. assembly features, in context, etc. I guess I dont grasp the "time" part.

 

[MDGroup]

swmetal,

My understanding is that 'Time dependant features' are features such that there results are affected by the order they appear in the feature tree.

Ex) Start with a block. Cut a hole thru it. Then create another extrusion that partially blocks the thru-hole.

Now, re-order the features so that the cut (hole) is after the second extrusion.

You have the same features, but in the first scenario the hole is not completely thru the part, but is partially blocked. In the second scenario, the hole cuts thru everything because it was created later in the feature manager.

Time Dependepen Features and features that will create different results depending on the order they are executed. (Features are built in succession, results depend on what time(order) each is created)

On the contrary, an example of a Non-Time Dependent feature would be offsetting one of the reference planes. It doesn't matter when in the model you create this, it will always be the same.

Hope this helps explain it a little,
Lou

 

[swmetal]

Thanks GLED
Seems they should be "order dependant features". I guess symantics. Thanks

 

[MadMango]

GLED, I don't think your explanation is accurate.

Assembly cuts are an example of time dependent features. For example, your design requires welding a block with holes to another block without holes, then having the holes matched drilled. You would create the match drilled holes in the weldment assembly, not in the individual block part models.

"Art without engineering is dreaming; Engineering without art is calculating."

Have you read faq731-376 to make the best use of Eng-Tips Forums?

 

[MDGroup]

MadMango,

I think you are correct

In searching a little, I found a brief explanation.

Time Dependent Featrues:
They are basically anything that comes after the mates in the assembly. The reason these are important are that in an assembly, the part must be solved first, then the mates.

Thanks for correcting me,
Lou