# Navigation in 3D slicer

**URL:** <https://discourse.slicer.org/t/navigation-in-3d-slicer/40404>\
**Category:** Support\
**Created:** [November 27, 2024, 12:54pm UTC](https://discourse.slicer.org/t/navigation-in-3d-slicer/40404 "2024-11-27T12:54:00Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![mayaambar](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/mayaambar/32/76746_2.png) [@mayaambar](https://discourse.slicer.org/u/mayaambar)\
**Post date:** [November 27, 2024, 12:54pm UTC](https://discourse.slicer.org/t/navigation-in-3d-slicer/40404/1 "2024-11-27T12:54:00Z")

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Hello, I’m trying for weeks to do registration to a heart model… and its never seems to be accurate enough.  
here is the process in which Im doing the registration:

1. Im making a pivot and spin caliberation, usually Im not able to get a RMS smaller than 1, I apply the transformation to the needle
2. I move the needle to a specific points on the model or making a route with the sensor on a specific vein then those point I collected is a point list called NP1
3. then im making a new point list called LA(left artium) and put the point on the same locations that the needle was on the model
4. Im using registration=\> fiducial registration to make a transformation and choosing a linear transformation.
5. I apply the linear transformation to the needle…

after this the needle is closed to where it suppost to be but there are some error- for instance - sometimes it goes out of the model when it is still suppost to be in the model  
our model is elastic so we think this may be an issue - the model is moving sometimes - we are thinking of printing a harden model.  
before we do that- is the process I describe seems ok? how can I improve it?

thank you for reading this and for all your help  
Maya