Pattern Curve with variable / increasing spacing

[joerjohnson]

Hello,

I am trying to create an array of lines inside of a sketch where the spacing between the line increases as more instances of the lines are added.

For example I would like lines spaced at 1,2,4,7,11,16,22mm, etc. I have looked at selecting formula or function as the dimension for the spacing, but this doesn't seem to have that option.

It's basically a gradient of lines. Any ideas?

 

[JohnRBaker]

By definition, a 'Pattern' will always be equally spaced and all instances will be controlled by a single set of Expressions.

John R. Baker, P.E.
Product 'Evangelist'
Product Engineering Software
Siemens PLM Software Inc.
Digital Factory
Cypress, CA
Siemens PLM:
UG/NX Museum:

To an Engineer, the glass is twice as big as it needs to be.

 

[joerjohnson]

Is there anything in NX 7.5 that will allow placement non-equally spaced objects?

 

[JohnRBaker]

Not and have it as part of a 'Pattern'.

John R. Baker, P.E.
Product 'Evangelist'
Product Engineering Software
Siemens PLM Software Inc.
Digital Factory
Cypress, CA
Siemens PLM:
UG/NX Museum:

To an Engineer, the glass is twice as big as it needs to be.

 

[joerjohnson]

Are you suggesting the only way to do this is manually dimension the lines to space them out?

 

[JohnRBaker]

Yes. Of course, if you plan to do this a lot, you could always write a custom application which could place multiple copies of a selected object using whatever spacing rule that you would wish to program into the app.

John R. Baker, P.E.
Product 'Evangelist'
Product Engineering Software
Siemens PLM Software Inc.
Digital Factory
Cypress, CA
Siemens PLM:
UG/NX Museum:

To an Engineer, the glass is twice as big as it needs to be.

 

[PSI-CAD]

Hi,

I know that you are in NX7.5 but starting with NX8.5 a new expression type "list" exist now

You can define list={1,2,4,7,11,16,22}

then for example:

1°) extract the third element "4" by using: num3=third(list)

2°) a list that contain only the fifth element by using
sublist=sublist(list,5,5)

...





Regards
Didier Psaltopoulos

http://www.psi-cad.com

 

[JohnRBaker]

I'm not sure that would even work using any of the Pattern functions if we're only talking about patterning a curve. And it certainly will not work inside of a Sketch, in any release.

John R. Baker, P.E.
Product 'Evangelist'
Product Engineering Software
Siemens PLM Software Inc.
Digital Factory
Cypress, CA
Siemens PLM:
UG/NX Museum:

To an Engineer, the glass is twice as big as it needs to be.

 

[PSI-CAD]

Hi,

It seems that the following part is doing the job ,isn'it ?

Regards
Didier Psaltopoulos

http://www.psi-cad.com

 

[JohnRBaker]

Yes, but that's not using a Pattern, either inside or outside a Sketch, which is what the OP originally was asking for. Besides, 'List' expressions were not added to NX until NX 8.0 and the OP is using NX 7.5.

That being said, using NX 7.5 you could create a set of 'Offset' cuves in the Sketch (not exactly a 'Pattern', but close), with the general 'Continous Auto Dimensioning' option toggled ON and the Offset Curve specific 'Create Dimension' option toggled OFF. This way temporary dimensions will be assigned to each offset curve which can later be edited to the desired values, as I've done in the NX 7.5 example attached below.

John R. Baker, P.E.
Product 'Evangelist'
Product Engineering Software
Siemens PLM Software Inc.
Digital Factory
Cypress, CA
Siemens PLM:
UG/NX Museum:

To an Engineer, the glass is twice as big as it needs to be.

 

[joerjohnson]

Thanks for these suggestions.

John, I understand your work-around using offset curves and auto-dimensioning.

Didier - What you say makes sense too.

Both of these ways are not automated, which is what I was trying to achieve. I have to either write in the dimensions (JohnR) or write 'first(list)' for every dimension (Didier) so neither get at exactly what I was going for, but thank you for taking the time to think about the problem.