topic Curve driven pattern in Inventor Forum

Curve driven pattern

J.Oye — Mon, 24 Feb 2025 17:04:46 GMT

I've attached a screenshot of a sheetmetal part where I have a hole placed centered at the bottom of the part. I want the hole to be patterned around the perimeter where the spacing will stay around 2" <> even If the size of the sheetmetal part changes...so If width or height of part varies. I know you can't link to the length of a curve in Inventor so wondering what other options I have. I don't really want to add a dimension to the 2 vertical sketches as well as the 2 horizontal sketches and then do simple math to round to the nearest integer.

Re: Curve driven pattern

LT.Rusty — Mon, 24 Feb 2025 18:43:36 GMT

You actually *can* link to the length of a curve, but it gets messy and it’s probably not the right way to do things.

Take a look at what I did in the attached file. In the parameters there’s a unit mismatch between inches and unit less, which Inventor resolves as being centimeters, apparently, so I have to divide the curve length by 2.54 to get it back to inches, and then divide that by 2 to get the correct number of holes, which then shows an error due to expecting unit less but finding inches… but it’s not a fatal error, and it will allow you to actually do it.

I tested this part with changing the outside dimensions, and it seems to be fairly robust- I didn’t get any errors beyond the one already described.

Re: Curve driven pattern

SBix26 — Mon, 24 Feb 2025 23:52:30 GMT

This works great, especially with a few tweaks to equations:

Instead of the "round" function you can use "floor" (round down) or "ceil" (round up), depending on your needs. You could also add a user parameter for the preferred spacing, to be used in both the holeQuan parameter and Sketch2 (not shown above).

Sam B

Inventor Pro 2025.2.1 | Windows 11 Home 24H2

Re: Curve driven pattern

LT.Rusty — Tue, 25 Feb 2025 00:37:44 GMT

Interesting- adding the round function actually cleans up the unitless error. I didn't realize that would happen.

Yeah, that's a definite improvement.

Re: Curve driven pattern

SBix26 — Tue, 25 Feb 2025 00:40:32 GMT

No, I changed the units on the "2" from unitless to inches. The round function requires a unitless argument.

Sam B

Inventor Pro 2025.2.1 | Windows 11 Home 24H2