Variables in patterns. 1

[T1936]

Hi,

I am trying to develop a pattern of simple rectangular protrusions. What I need to do is have each instance of the pattern slightly longer than the one before it, based on a formula. The overall length of the pattern is variable driven as well.

Is this possible with the pattern along curve tool? I think I know the answer, as I have tried this, and it appears that variables are not applied to instances in a pattern. That said, any suggestions on how I could accomplish this task?

Thanks.

 

[donyoung]

Hi,

what you are trying is impossible with a pattern. A pattern of an
item is only a shortcut to place that part manually at different
places. It is in fact always the same feature or part. So a change
on the master feature/part will affect all patterned items.
To get what you want you succeed by pattering a construction surface
On the surfaces you may place your protrusions which now can be
changed individually because they are unique.
To have a surface patterned on the x/y plane draw a short line on
either the y/z or x/z plane. the line should be colinear to the
horizontal axis. Then extrude that line symmetric to any width.
Now pattern this surfce either circular or rectangular.

HTH
dy

 

[donyoung]

/Edit

One other approach may be this one (easy):
- draw your rectangle and extrude it to the minimum height
- now pattern this extruded item.

Then use the Modify --> Modify Face to adjust the height which
can be done on each individual item. Just pick the top face
and move it. The amount moved is stored in a variable and
thus can be adjusted by a formula

To accomplish this you must have SE V17

dy

 

[Schipperus]

It is possible to pattern these occurences, but it's not very easy, and the bottoms should be on a solid.

So the way to do this is make the first protrusion upside down (on a parallel plane) and make it extrude to next (which should be the solid which is your baseplane).

Then make a curve which contains the variables you need (length and height change). Pattern the feature along this curve, since they extrude to next the length will vary.

Difficulties of course are: Make the curve follow the right path, make the steps the right distance (try it, it's not easy).

Hope it helps, IJsbrand Schipperus

 

[donyoung]

Hi IJsbrand,

interesting approach -- never thought of that. I posted a
simple example here (I hope I got it right):

Var-Pattern

dy

 

[Schipperus]

DY,

that's exactly the pattern I created. I was just to lazy to upload the sample to this forum!!

IJsbrand

 

[T1936]

Thanks for the suggestions! The modify faces worked exactly as I needed.

Tim