Method for determining the spatial position of objects

Abstract

The present invention relates to a method for determining the spatial position of objects, in particular medical objects. First position data is acquired that describes a spatial position of an object in a first coordinate system. First transformation data is acquired that transforms the object's position from the first coordinate system to a second coordinate system. Based on the foregoing data, second position data is acquired that specifies the spatial position of the object in the second coordinate system. Second transformation data is acquired that transforms the object's position from the second coordinate system to an inertial coordinate system. Based on the second position data and the second transformation data, inertial position data is determined that specifies a position of the object in the inertial coordinate system.

1 . A data processing system, comprising at least one computer having at least one processor configured to execute a computer-implemented medical data processing method for determining the spatial position of medical objects, the data processing method comprising the steps of:
 acquiring, at the processor and via a medical tracking system comprising a sensor array, first position data which comprise first position information describing the spatial position of an object within a first co-ordinate system positionally assigned to said sensor array which is configured to determine the spatial position of at least one tracking marker attached to the object;   acquiring, at the processor, first transformation data which comprise first transformation information describing a transformation of the object's position from the first co-ordinate system into a second co-ordinate system positionally assigned to an inertial sensor array which is attached to the medical tracking system's sensor array and configured to sense any motion of the medical tracking system's sensor array within an inertial co-ordinate system positionally assigned to a treatment room which accommodates the object;   acquiring, at the processor and on the basis of the first position data and the first transformation data, second position data which comprise second position information describing the spatial position of the object within the second co-ordinate system;   acquiring, at the processor, second transformation data which comprise second transformation information describing a transformation of the object's position from the second co-ordinate system into the inertial co-ordinate system;   determining, by the processor and on the basis of the second position data and the second transformation data, inertial position data which comprise inertial position information describing the spatial position of the object within the inertial co-ordinate system.   
     
     
         2 . A computer implemented medical data processing method for determining the spatial position of medical objects, the method comprising executing, on at least one processor of at least one computer, the steps of:
 acquiring at the processor and via a medical tracking system comprising a sensor array, first position data which comprise first position information describing the spatial position of an object within a first co-ordinate system positionally assigned to said sensor array which is configured to determine the spatial position of at least one tracking marker attached to the object;   acquiring, at the processor, first transformation data which comprise first transformation information describing a transformation of the object's position from the first co-ordinate system into a second co-ordinate system positionally assigned to an inertial sensor array which is attached to the medical tracking system's sensor array and configured to sense any motion of the medical tracking system's sensor array within an inertial co-ordinate system positionallly assigned to a treatment room which accommodates the object;   acquiring, at the processor and on the basis of the first position data and the first transformation data, second position data which comprise second position information describing the spatial position of the object within the second co-ordinate system;   acquiring, at the processor, second transformation data which comprise second transformation information describing a transformation of the object's position from the second co-ordinate system into the inertial co-ordinate system;   determining, by the processor and on the basis of the second position data and the second transformation data, inertial position data which comprise inertial position information describing the spatial position of the object within the inertial co-ordinate system.   
     
     
         3 . (canceled) 
     
     
         4 . The method according to  claim 2 , wherein the second co-ordinate system corresponds to the first co-ordinate system. 
     
     
         5 . The method according to any one of  claim 2 , wherein the inertial position data are stored for at least one object and in particular for a plurality of points which are palpated during a point acquisition and registration procedure, wherein the tracked object is a point acquisition instrument, in particular a pointer instrument. 
     
     
         6 . (canceled) 
     
     
         7 . A tracking system for determining the spatial position of medical objects comprising:
 a sensor array which is configured to determine the spatial position of at least one tracking marker attached to an object;   an inertial sensor array which is attached to said sensor array; and   the computer of  claim 14 .   
     
     
         8 . The tracking system according to  claim 7 , wherein the sensor array comprises at least one sensor selected from the group consisting of:
 optical cameras, which are sensitive to infrared light;   EM (electromagnetic) tracking sensors;   ultrasound tracking sensors.   
     
     
         9 . The tracking system according to  claim 7 , wherein the inertial sensor array comprises at least one sensor selected from the group consisting of:
 accelerometers;   sensors or sensor arrangements which are configured to be sensitive to the earth's gravitational field;   magnetometers;   gyroscopes;   optical cameras, which are sensitive to infrared light;   pressure sensors which are sensitive to atmospheric pressure.   
     
     
         10 . The tracking system according to  claim 7 , wherein at least the sensor array and the inertial sensor array are freely movable. 
     
     
         11 . The tracking system according to  claim 10 , wherein the sensor array and the inertial sensor array are housed in a common unit that is configured to be worn by a person, as a device similar to spectacles, and to provide the wearer with additional information based on the determined spatial position of the at least one object. 
     
     
         12 . The tracking system according to  claim 7 , which is also configured to process signals from at least one sensor assigned to the tracking system, which is in turn configured to detect the motion of an untracked object within the inertial co-ordinate system and comprises at least one pressure sensor which is arranged between a part of a patient's body and a supporting structure and allows an indication as to whether said object has moved. 
     
     
         13 . A non-transitory computer-readable program storage medium storing a computer program which, when executed on a processor of a computer or leaded into the memory of a computer, causes the computer to perform a computer-implemented medical data processing method for determining the spatial position of medical objects, the data processing method comprising the steps of:
 acquiring, at the processor and via a medical tracking system comprising a sensor array, first position data which comprise first position information describing the spatial position of an object within a first co-ordinate system positionally assigned to said sensor array which is configured to determine the spatial position of at least one tracking marker attached to the object;   acquiring, at the processor, first transformation data which comprise first transformation information describing a transformation of the object's position from the first co-ordinate system into a second co-ordinate system positionally assigned to an inertial sensor array which is attached to the medical tracking system's sensor array and configured to sense any motion of the medical tracking system's sensor array within an inertial co-ordinate system positionally assigned to a treatment room which accommodates the object;   acquiring, at the processor and on the basis of the first position data and the first transformation data, second position data which comprise second position information describing the spatial position of the object within the second co-ordinate system;   acquiring, at the processor and on the basis of the first position data and the first transformation data, second position data which comprise second position information describing the spatial position of the object within the second co-ordinate system;   acquiring, at the processor, second transformation data which comprise second transformation information describing a transformation of the object's position from the second co-ordinate system into the inertial co-ordinate system;   determining, by the processor and on the basis of the second position data and the second transformation data, inertial position data which comprise inertial position information describing the spatial position of the object within the inertial co-ordinate system.   
     
     
         14 . A computer comprising the non-transitory computer-readable program storage medium according to  claim 13 . 
     
     
         15 . A medical tracking system for determining a spatial position of medical objects within a treatment room, comprising:
 a sensor array configured to determine a spatial position of an object within a first coordinate system, wherein the first coordinate system is defined relative to the sensor array;   an inertial sensor array configured to detect motion of the sensor array relative to a global coordinate system associated with the treatment room; and   a computer having at one processor configured to execute a computer program that configures the processor to:
 acquire, via the sensor array, first position information that indicates the position of the object within the first coordinate system; 
 acquire first transformation information that describes a transformation from the first coordinate system to a second coordinate system, wherein the second coordinate system is defined relative to the inertial sensor array; 
 transform the position of the object from the first coordinate system to the second coordinate system based on the first position information and the first transformation information; 
 acquire second transformation information that describes a transformation from the second coordinate system to the global coordinate system based on motion detected by the inertial sensor array; and 
 determine global position information that describes the position of the object within the global coordinate system of the treatment room. 
   
     
     
         16 . The medical tracking system of  claim 15 , wherein the sensor array and the inertial sensor array are freely movable at least within the treatment room. 
     
     
         17 . The medical tracking system of  claim 15 , further comprising a common unit housing the sensor array and the inertial sensor array. 
     
     
         18 . The medical tracking system of  claim 17 , wherein the common unit is a wearable, spectacle-like device. 
     
     
         19 . The medical tracking system of  claim 18 , wherein the wearable, spectacle-like devices includes a head-mounted display. 
     
     
         20 . The medical tracking system of  claim 15 , wherein the inertial sensor array is attached to sensor array. 
     
     
         21 . The medical tracking system of  claim 15 , wherein the first coordinate system corresponds to the second coordinate system. 
     
     
         22 . The medical tracking system of  claim 15 , wherein the sensor array determines the spatial position of the object within the first coordinate system based on at least one tracking marker attached to the object.