View source for PET-CT/Documentation/Modules/Pivot Calibration

== Introduction and Acknowledgements == 
Author: Guillaume Sala, [http://www.kitware.com Kitware]<br>
Contributor: Andinet Enquobahrie, [http://www.kitware.com Kitware]<br>
Acknowledgements: This work is supported by NIH grants 2R42CA153488-02A1 and R41CA153488-01 "Improving liver lesion biopsy in the CT suite through fusion with PET images"<br>
Contact: Andinet Enquobahrie, Guillaume Sala<br>

== Module Description ==

The PivotCalibration module allows to run a pivot calibration algorithm (Using [https://www.assembla.com/spaces/plus/wiki Plus library]) for a given tracker device. Once a tracking device connection is established with Slicer, the pose information for the markers are collected. This module is useful when we want to determine and track the tip of the tool instead of the markers. It calculates the transformation matrix from the marker to the tool tip coordinate system.<br>

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[[File:PivotCalibration-GUI.png|thumb|center|500px|PivotCalibration Module]]
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[[File:ToolTipCalibrationIllustration.png|thumb|center|150px|Pivot Calibration Illustration]]
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== Panels ==
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* '''Pivot Transform''': The tracker selection combobox allows select the transform corresponding to the tracking device. The transform in this combobox will be used to compute the pivot calibration transform.

* '''Number of points to acquire''': Choose the number of points to use to run the algorithm
* '''Output''': The current coordinate of the tracker is displayed while acquiring the points and the computed transform is displayed when it is generated.
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|[[File:PivotCalibrationPanel.png|thumb|400px|Pivot calibration panel]]
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== Tutorial ==

*Use [http://www.slicer.org/slicerWiki/index.php/Documentation/4.2/Modules/OpenIGTLinkIF OpenIGTLinkIF] to establish connection between Slicer and the tracker device.
**Using IGSTK: run the executable [http://public.kitware.com/IGSTKWIKI/index.php/Using_OpenIGTLink_in_IGSTK#Broadcast_Tracking_data_using_OpenIGTLink OpenIGTLinkTrackerBroadcasting] giving a configuration file for the given tracking system (e.g [[Media:IGSTK_polarisHybridConfiguration.xml|Polaris configuration file]], [[Media:IGSTK_micronConfiguration.xml|Micron configuration file]])

*In the PivotCalibration module
**Select the transform node corresponding to the tracker.
**Select the number of points to acquire for the pivot calibration
**Start calibration and move the tracker around a fixed point while the module computes the transform