System and method for controlling scanning planes of imaging device

Patent metadata

Field	Value
Publication number	US-9303985-B2
Application number	US-201013636545-A
Country	US
Kind code	B2
Filing date	Jun 25, 2010
Priority date	Mar 22, 2010
Publication date	Apr 5, 2016
Grant date	Apr 5, 2016

Abstract

This patent indicates a type of system and method for controlling scanning planes of imaging device, it includes: tracer, on which a tracer coordinate system is built, is fixed on the target which is to be scanned; a tracking device, on which a tracking device coordinate system is built, is used to get the position and orientation of the tracer in the tracking device coordinate system and convert the known position and orientation of the target which is to be scanned from the tracer coordinate system to the tracking device coordinate system; an imaging device, on which an imaging device coordinate system is built, is used to scan the position and orientation of the said target to be scanned in the imaging device coordinate system to form images; a conversion module, which is preset in the tracking device or the imaging device, is used to convert the position and orientation of the target which is to be scanned from the tracking device coordinate system to the imaging device coordinate system; when the conversion module is preset in the tracking device, the tracking device transfers the position and orientation of the target which is to be scanned in the tracking device coordinate system to the imaging device. This patent has the ability to provide high efficiency, and high precision when scanning target image, it can be used at any type of image devices.

First claim

What is claimed is:

1. A system for controlling scanning planes of imaging device, comprising:
a tracer, on which a tracer coordinate system is built, fixed on a target which is to be scanned;
a tracking device, on which a tracking device coordinate system is built, for obtaining the position and orientation of the tracer in said tracking device coordinate system and converting the known position and orientation of the target to be scanned from a coordinate system of said tracer to a coordinate system of said tracking device; and
an imaging device, for scanning the position and orientation of the target to be scanned in said coordinate system of said imaging device to form images, on which an imaging device coordinate system is built;
wherein, said tracking device or said imaging device has a conversion module preset therein, which is for converting the position and orientation of the target to be scanned from the tracking device coordinate system to the imaging device coordinate system; and when the conversion module is preset in the tracking device, the tracking device transfers the position and orientation of the target to be scanned in the tracking device coordinate system to the imaging device;
and a way of implementation of said system comprises
step 1: building a system comprising a tracer, a tracking device, and an imaging device; and then fixing said tracer a target to be scanned; and, presetting a conversion module for conversion between a tracking device coordinate system and an imaging device coordinate system in a tracking device or a imaging device;
step 2: defining a plane through which said imaging device scans a target to be scanned as a scanning plane G, and an expression of formula of said scanning plane G in said tracer coordinate system is presented as:
{right arrow over (n)} tool ·( X tool −S tool )=0

wherein , X tool represents a coordinate of any point on said scanning plane G in said tracer coordinate system ‘tool’, which is 3 dimensional vector; {right arrow over (n)} tool represents a normal vector of said scanning plane G in the tracer coordinate system, which is a normalized 3 dimensional vector; S tool represents a coordinate of a known point on said scanning plane G in the tracer coordinate system, which is 3 dimensional vector;
step 3: measuring a position and orientation C tool track of said tracer 1 in said tracking device coordinate system ‘track’ with said tracking device 2 ;
Step 4: calculating a first plane equation of scanning plane G in the tracking device coordinate system with the tracking device using the position and orientation C tool track of step 3, wherein, an expression of said first plane equation is presented as bellow:
{right arrow over (n)} track ·( X track −S track )=0

{right arrow over (n)} track =R tool track ·{right arrow over (n)} tool
S track =R tool track ·S tool +T tool track

in which {right arrow over (n)} track represents a normal vector of said scanning plane G in said tracking device coordinate system, which is a normalized 3 dimensional vector; X track represents a coordinate of any point on said scanning plane G in said tracking device coordinate system, which is a 3 dimensional vector; and S track represents a coordinate of a known point on said scanning plane G in said tracking device coordinate system, which is a 3 dimensional vector;
step 5: calculating a second plane equation of said scanning plane G in said imaging device coordinate system in terms of a conversion module C track scan for conversion between said tracking device coordinate system and said imaging device coordinate system, wherein, an expression of said second plane equation is presented as bellow:
{right arrow over (n)} scan ·( X scan −S scan )=0

{right arrow over (n)} scan =R track scan ·{right arrow over (n)} track =R track scan ·R tool track ·{right arrow over (n)} tool
S scan =R track scan ·S track +T track scan =R track scan ·( R tool track ·S tool +T tool track )+ T track scan

in which {right arrow over (n)} scan represents a normal vector of said scanning plane G in said imaging device coordinate system, which is a normalized 3 dimensional vector; X scan represent a coordinate of any point on said scanning plane G in said imaging device coordinate system, which is a 3 dimensional vector; S scan represents a coordinate of a known point on said scanning plane G in the imaging device coordinate system, which is a 3 dimensional vector; and
Step 6: scanning said target to be scanned with said imaging device 3 , in terms of said second plane equation calculated in step 5.

2. The system of claim 1 , wherein, the expression of said conversion module C track scan is presented as:

C
track
scan

=

(

R
track
scan

T
track
scan

0

1

)

C track scan is a 4*4 matrix, R track scan is a 3*3 rotation matrix, and T track scan is a 3 dimensional translation vector.

3. The system of claim 2 , wherein, said tracer comprises
a position/orientation sensor and a fixing support;
a position/orientation sensor is fixed via said fixing support on said target to be scanned; and
a position and orientation of said position/orientation sensor is the same as a position and orientation of said tracer.

4. The system of claim 1 , wherein, said tracer comprises
a position/orientation sensor and a fixing support;
a position/orientation sensor is fixed via said fixing support on said target to be scanned; and
a position and orientation of said position/orientation sensor is the same as a position and orientation of said tracer.

5. The system of any one of claim 1 - 4 , wherein,
an expression of said position and orientation C tool track of said tracer in said tracking device coordinate system is presented as:

C
tool
track

=

(

R
tool
track

T
tool
track

0

1

)

and C tool track is a 4*4 matrix, R track scan is a 3*3 rotation matrix, and T track scan is a 3 dimensional translation vector.

Assignees

• Zhao Lei
• Wei Wei
• Liu Huagen
• Symbow Medical Technology Co Ltd

Inventors

• Zhao Lei
• Wei Wei
• Liu Huagen

Classifications

• A61B6/035

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• A61B8/0841

  for locating instruments · CPC title

• A61B2017/00207

  with hand gesture control or hand gesture recognition · CPC title

• A61B6/12

  Arrangements for detecting or locating foreign bodies · CPC title

• G01C5/00 Primary

  Measuring height; Measuring distances transverse to line of sight; Levelling between separated points; Surveyors' levels (G01C3/20, G01C3/30 take precedence) · CPC title