Shoelast

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microelly2
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Re: Shoelast

Post by microelly2 »

toward the scanned shoe:
https://youtu.be/u28heuCTUjk

so I ask for more test data
If there is somebody who whats to share his shoe last data with is project:
more test data for different shoelast layouts from reality will help to go into the right direction.
what we need is a scan (obj or stl) of the model.
kridhond
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Re: Shoelast

Post by kridhond »

I'll try to get an example this week. I expect it to be Friday.
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microelly2
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Re: Shoelast

Post by microelly2 »

https://youtu.be/7gU2jaKNYUI

EDIT:
to make the work with the sketchers easier there was this idea :lol:
https://youtu.be/J4kD1LLP3uU
kridhond
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Re: Shoelast

Post by kridhond »

Hi again!

I tried to attach an stl-file of a shoelast but the file is too large (altough it's only 4Mb). I'll get the file to microelly2 in another way so soon you'll be seeing some pictures of it :-)

In a perfect world, that would be the output of the freecad-model with the following data (I refer to the parametric model I suggested some posts ago):

LL (last length) : 247 mm
H10 (heel rise) = 17 mm
Other parameters as default

Joint = 245 mm
Girth = 235 mm
Waist = 230 mm
Instep (around the heel) = 315 mm

Hope we can get to a working model. I'd love to do some real-life tests and feedback the results.

BR
Attachments
shoelastcontour2.jpg
shoelastcontour2.jpg (669.8 KiB) Viewed 2097 times
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microelly2
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Re: Shoelast

Post by microelly2 »

Thanks for the model, I have analysed the data and now we can see this model inside our model.
https://youtu.be/2xpaX3RPFi0

I will look next days (after easter) to reduce the ribs to our data model (from 90 to 14)
and hope to get a good enough approximation
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microelly2
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Re: Shoelast

Post by microelly2 »

demo sketcher proxy to edit tangent/directions in two control points,
https://youtu.be/Lt5wDYsu4qA

With the next version of FreeCAD we can hide the blue data and then we have only an simpilfied drawing interface.
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microelly2
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Re: Shoelast

Post by microelly2 »

Today I have looked how professional foot scanning works.
foot length and joint size are not very exact (or there is no shoe which fits the size of the scanned foot :lol: )
foot-scan.png
foot-scan.png (324.31 KiB) Viewed 1977 times
The idea is: green and yellow and red are easy to scan under rgb filters
the grid distances is about 5 mm

I'm now looking for such grid stockings ...
bp_475.png
bp_475.png (370.3 KiB) Viewed 1977 times
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NormandC
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Re: Shoelast

Post by NormandC »

kridhond wrote:I tried to attach an stl-file of a shoelast but the file is too large (altough it's only 4Mb).
4MB may not look much to you, but on an online forum that can see many images and files attached each day, it quickly adds up. The forum does not have unlimited hosting so a limit (currently 1MB I believe) has to be set.

That being said, an STL file can be compressed in ZIP format, it will greatly reduce its size.
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microelly2
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Re: Shoelast

Post by microelly2 »

the curve length of the rib in colors: red > max , blue < min
https://youtu.be/JbVJSx8ccuU
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microelly2
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Re: Shoelast

Post by microelly2 »

It's not possible to envelope a shoe last but it is a common practice to create 2D models by putting tape onto the last and then pulling it back.

The implementation of this process shows where the critial areas of such a process are.

In the example we start at the middle of the sole.
Starting somewhere else will gibe other results.


red: The isomap maximum error >10%
bp_498.png
bp_498.png (348.77 KiB) Viewed 1829 times
red: the isomap medium error >5%
bp_499.png
bp_499.png (376.1 KiB) Viewed 1829 times
the mapping of a circle pattern from 2D to the surface.
bp_500.png
bp_500.png (132.55 KiB) Viewed 1829 times
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