Tracking system and tracking method using the same

Patent metadata

Field	Value
Publication number	US-9576366-B2
Application number	US-201414370549-A
Country	US
Kind code	B2
Filing date	Jan 7, 2014
Priority date	Jan 10, 2013
Publication date	Feb 21, 2017
Grant date	Feb 21, 2017

Abstract

A tracking system and method using the same is disclosed which is capable of minimizing a restriction of surgical space by achieving a lightweight of the system as well as a reduction of a manufacturing cost through calculating a three-dimensional coordinates of each of makers using one image forming unit. In the tracking system and method using the same, lights emitted from the markers are transferred to one image forming unit through two optical paths, an image sensor of the image forming unit forms two images (direct image and reflection image) of the two optical paths of the markers, and therefore, the system and method using the same has an effect of reducing a manufacturing cost of the tracking system with small and lightweight, and relatively low restriction of surgical space comparing with conventional tracking system since it is possible to calculate a spatial position and direction of the markers attached on a target by using one image forming unit.

First claim

The invention claimed is:

1. A tracking system comprising:
at least three markers attached on a target and emitting lights or reflecting lights emitted from at least one light source;
a reflector reflecting the lights which are emitted from the markers or the lights reflected by the markers;
an image forming unit which forms a direct image by directly receiving lights emitted from the markers and, at the same time, forms a reflection image by receiving lights reflected from the reflector after being emitted from the markers; and
a processor which calculates three-dimensional coordinates of the markers using the direct image and the reflection image formed on the image forming unit, and calculates a spatial position and direction of the target by comparing the three-dimensional coordinates of the markers with a pre-stored geometric information between the markers adjacent to each other.

2. The tracking system of claim 1 , wherein the reflector is a mirror which reflects lights emitted from the markers towards the image forming unit to form a reflection image.

3. The tracking system of claim 1 , wherein the reflector is positioned on a same optical path as the image forming unit, and changes an image forming position of the reflection image by changing at least one of an installation position, an angle, and a shape of a reflection surface under the control of the processor.

4. The tracking system of claim 1 , wherein the image forming unit is a camera which forms an image by receiving the light emitted from the markers and the lights reflected from the reflector.

5. The tracking system of claim 1 , wherein the geometric information between the markers comprises length information of straight lines which connect the markers adjacent to each other, and angle information which is formed by a pair of straight lines adjacent to each other.

6. A tracking method comprising:
forming a direct image on a n image forming unit by directly receiving lights emitted from at least three markers attached on a target and, at the same time, forming a reflection image by receiving lights reflected from a reflector that is installed in a specific area to reflect lights emitted from the markers;
calculating three-dimensional coordinates of each of the markers through a processor by using the direct image and reflection image of the markers formed on an image forming unit; and
calculating a spatial position and a direction of the target by comparing the three-dimensional coordinates of each of the markers and geometric information between the markers adjacent to each other, wherein the geometric information is pre-stored in the processor.

7. The tracking method of claim 6 , wherein the geometric information comprises length information of straight lines which couple the marker adjacent to each other and angle information which is formed by the pair of straight lines adjacent to each other.

8. The tracking method of claim 6 , wherein forming the reflection image on the image forming unit comprises controlling at least one of an installation position, an angle, and a shape of a reflection portion of the reflector through the processor to change an image forming position of the reflection image on a same optical path.

9. The tracking method of claim 6 , wherein calculating the three-dimensional coordinates of the markers comprises calculating two-dimensional coordinates of the direct and reflection images of the markers through the processor; and
calculating the three-dimensional coordinates of the markers through the processor by using the two-dimensional coordinates of the direct and reflection images of the markers.

Assignees

• Koh Young Tech Inc
• Kyungpook Nat Univ Industry-Academic Coop Found

Inventors

• Hong Jong-Kyu
• Lee Hyun-Ki
• Kim Min-Young
• Chung Jae-Heon

Classifications

• A61B2090/3937

  Visible markers · CPC title

• G06T2207/30204

  Marker · CPC title

• G06T7/0044 Primary

  Physics · mapped topic

• A61B2090/3983

  Reference marker arrangements for use with image guided surgery · CPC title

• G06T2207/10028

  Range image; Depth image; 3D point clouds · CPC title