B-Spline path array with defined spacing

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Sigli
Posts: 6
Joined: Mon Mar 30, 2020 4:18 pm

B-Spline path array with defined spacing

Post by Sigli » Mon Mar 30, 2020 4:34 pm

Hi

I'm trying to create an array of parts that follow the path of a b-spline. I would like the parts to be precisely spaced along the length of the b-spline and not necessarily be equidistant.

Using the path array is the closest I have got to achieving this but the array turns out to be oriented differently from the initial part's orientation and none of the placement modifiers can remedy this. Additionally, I cannot see a way to adjust the spacing between the individual parts of the array.

If anyone can suggest a solution to this it would be greatly appreciated. Thank you!
TheMarkster
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Joined: Thu Apr 05, 2018 1:53 am

Re: B-Spline path array with defined spacing

Post by TheMarkster » Mon Mar 30, 2020 11:17 pm

Instead of an array it might be better to make as many draft clones of the object as needed and attach each in turn to the bspline. Adjust the map path parameter (a value between 0.0 and 1.0) to place each at its desired location along the bspline. Apply the attachment offset properties, such as rotation and offset, to each clone to align it as desired. Perhaps if you attach your file it would help to understand better what you try to do.
My FreeCAD video series on youtube: https://www.youtube.com/c/mwganson
freedman
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Location: Washington State, USA

Re: B-Spline path array with defined spacing

Post by freedman » Tue Mar 31, 2020 2:49 am

I rarely recommend using a spreadsheet to new users but this might be the best approach. You can have full view of each parts properties all in list form. Using 0.19 could also be useful with it's ease of linking abilities.
Sigli
Posts: 6
Joined: Mon Mar 30, 2020 4:18 pm

Re: B-Spline path array with defined spacing

Post by Sigli » Tue Mar 31, 2020 3:49 am

The pad object and the b-spline path I would like to distribute it along
spline_with_pad.png
spline_with_pad.png (6.98 KiB) Viewed 155 times

Result via path array with align set to false
allign_False.png
allign_False.png (8.52 KiB) Viewed 155 times

Result with align set to true
align_true.png
align_true.png (13.57 KiB) Viewed 155 times
Attachments
path_file.FCStd
(10.37 KiB) Downloaded 2 times
Sigli
Posts: 6
Joined: Mon Mar 30, 2020 4:18 pm

Re: B-Spline path array with defined spacing

Post by Sigli » Tue Mar 31, 2020 3:58 am

TheMarkster wrote:
Mon Mar 30, 2020 11:17 pm
Instead of an array it might be better to make as many draft clones of the object as needed and attach each in turn to the bspline. Adjust the map path parameter (a value between 0.0 and 1.0) to place each at its desired location along the bspline. Apply the attachment offset properties, such as rotation and offset, to each clone to align it as desired. Perhaps if you attach your file it would help to understand better what you try to do.
How would you suggest that I attatch the object to the b-spline? Currently i am using sketcher/part design and when I attempt to 'fix a point onto an object', the b-spline, I am met with these error messages
edge_not_supported.png
edge_not_supported.png (4.7 KiB) Viewed 152 times
wrong_selection.png
wrong_selection.png (6.25 KiB) Viewed 152 times
Sigli
Posts: 6
Joined: Mon Mar 30, 2020 4:18 pm

Re: B-Spline path array with defined spacing

Post by Sigli » Tue Mar 31, 2020 4:03 am

freedman wrote:
Tue Mar 31, 2020 2:49 am
I rarely recommend using a spreadsheet to new users but this might be the best approach. You can have full view of each parts properties all in list form. Using 0.19 could also be useful with it's ease of linking abilities.
Thanks for the tip. I'll look into spreadsheets.
TheMarkster
Posts: 1353
Joined: Thu Apr 05, 2018 1:53 am

Re: B-Spline path array with defined spacing

Post by TheMarkster » Tue Mar 31, 2020 4:38 am

Snip macro screenshot-f57c8c.png
Snip macro screenshot-f57c8c.png (142.88 KiB) Viewed 138 times
Attachments
path_file_v2.FCStd
(23.74 KiB) Downloaded 4 times
My FreeCAD video series on youtube: https://www.youtube.com/c/mwganson
freedman
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Joined: Thu Mar 22, 2018 3:02 am
Location: Washington State, USA

Re: B-Spline path array with defined spacing

Post by freedman » Tue Mar 31, 2020 5:20 am

I have never done this before. It appears the "map path" is a distance down the path. It will be interesting if this satisfies the OP. Nice! :)
Attachments
map22.JPG
map22.JPG (36.29 KiB) Viewed 130 times
Sigli
Posts: 6
Joined: Mon Mar 30, 2020 4:18 pm

Re: B-Spline path array with defined spacing

Post by Sigli » Wed Apr 01, 2020 8:23 pm

TheMarkster wrote:
Tue Mar 31, 2020 4:38 am
Snip macro screenshot-f57c8c.png
Thanks for your help!

I'm not really sure how you attached the pad object to the B-Spline. Could you elaborate on that please? Whenever I try this I get those error messages that I posted above.

In the solution your provided (thank you very much!), from what I can see, when using this method you are unable to adjust the orientation of the pad object to meet my specifications. The object needs to be oriented like it is in the first image I provided (top down view).
spline_with_pad.png
spline_with_pad.png (6.98 KiB) Viewed 57 times
As far as the placement of the object on the spline, I am only able to adjust the map path parameter from 0-1 with 2 digits of precision. In order to accomplish my task I would require 3 digits of precision (0.115 for example). Ideally a solution that could, for example, allow me to place one pad object 60mm down the length of the spline (I can move towards arcs or a single arc if I have to) and another 80mm would be the best for my uses.

Thank you very much for any assistance you can provide!
Sigli
Posts: 6
Joined: Mon Mar 30, 2020 4:18 pm

Re: B-Spline path array with defined spacing

Post by Sigli » Wed Apr 01, 2020 8:24 pm

freedman wrote:
Tue Mar 31, 2020 5:20 am
I have never done this before. It appears the "map path" is a distance down the path. It will be interesting if this satisfies the OP. Nice! :)
I guess we're both new to this :D
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