# VMTK Mapping and Patching Error

**URL:** https://discourse.slicer.org/t/vmtk-mapping-and-patching-error/37684
**Category:** VMTK
**Tags:** python
**Created:** [August 3, 2024, 3:13pm UTC](https://discourse.slicer.org/t/vmtk-mapping-and-patching-error/37684 "2024-08-03T15:13:52Z")
**Posts on this page:** 1
**Page:** 1

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### Author: ![Michael\_C](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/michael_c/32/69578_2.png) [@Michael\_C](https://discourse.slicer.org/u/Michael_C)
#### Post date: [August 3, 2024, 3:13pm UTC](https://discourse.slicer.org/t/vmtk-mapping-and-patching-error/37684/1 "2024-08-03T15:13:52Z")

</div>

Dear all,

I am trying to map the surface of an aortic arch (in a .vtp format, as acquired from a SimVascular Simulation) onto the same parametric space, using [VMTK’s Mapping and Patching](http://www.vmtk.org/tutorials/MappingAndPatching.html).

The splitting and grouping seems to be correct. However when i proceed to the Metric mapping, the results differ from the ones shown in the website.

 ![image](https://us1.discourse-cdn.com/flex002/uploads/slicer/original/3X/f/6/f6b83b6dbcf2bf690d7bbd5c62d82540e0bc84dd.jpeg)

As shown below, at Case 1, the Harmonic Mapping takes place in only one branch/group instead of every single one (Example) and subsequently, the vmtkbranchpatching script leads to an error.

 ![Case 1](https://us1.discourse-cdn.com/flex002/uploads/slicer/original/3X/8/c/8c95e10c3961762055be57a657d63a3492c19b24.png)  
 ![Example](https://us1.discourse-cdn.com/flex002/uploads/slicer/original/3X/c/0/c0fe1f6bf35be21269011bf2b6b0673aa9f5ae2d.jpeg)

I tried smoothing the surfaces and cap any possible gaps but it didn’t work.

Any ideas and suggestions are welcome. Thank you in advance.

Best,  
Michael