KR102619164B1 - Real-time measuring method and apparatus for 3D direction of anterior pelvic plane - Google Patents

Abstract

The present invention relates to a method and device for real-time measurement of the three-dimensional direction of the anterior pelvic plane.
A three-dimensional real-time measurement method of the anterior pelvic plane according to an embodiment of the present invention includes attaching a sensor with a horizontal bar and a vertical bar extending from the center to the rear of the pelvis of an object, and an imaging unit measuring at least the front and sides of the object. capturing a plurality of images including, and having the sensor measure posture information simultaneously with the imaging; determining, by a control unit, an anterior pelvic plane based on the image of the object; and determining, by the control unit, an anterior pelvic plane based on the image of the object. Defining a local coordinate system based on the image and posture information, registering the local coordinate system of the sensor and the local coordinate system of the anterior pelvic plane by the control unit, and registering the local coordinate system of the anterior pelvic plane by the control unit, and position information measured by the sensor in real time. Based on this, determining the direction of the anterior pelvic plane.

Description

Real-time measuring method and apparatus for 3D direction of anterior pelvic plane}

The present invention relates to a method and device that can measure the three-dimensional direction of the anterior pelvic plane in real time.

The anterior pelvic plane is determined by the plane passing through the anterior superior iliac spines (ASIS) and the pubic symphysis (PS) of the pelvis.

In total hip replacement, it is very important to determine the location and direction of the implant corresponding to the femoral acetabulum, especially the anterior tilt angle. Side -Establish a surgical plan using the angle between the anterior pelvic plane and the coronal plane measured from the ray photograph. In this way, in artificial hip joint surgery, the anterior pelvic plane is used as an important indicator in surgical planning.

However, conventional methods only provide limited information for artificial hip joint surgery by measuring the two-dimensional angle in a specific posture. Since the actual human body shows three-dimensional movement in real time, in order to improve the success rate of artificial hip joint surgery, technology is used to measure three-dimensional orientation information of the anterior pelvic plane in real time during movements such as walking and climbing stairs. This is needed.

Korean Patent Publication KR 10-0617490 B1

The present invention is an invention to solve the above-mentioned problems, and can provide an invention that can improve the success rate of artificial hip joint surgery by measuring 3D direction information of the anterior pelvic plane in real time.

However, these problems are illustrative and the problems to be solved by the present invention are not limited thereto.

A three-dimensional real-time measurement method of the anterior pelvic plane according to an embodiment of the present invention includes attaching a sensor with a horizontal bar and a vertical bar extending from the center to the rear of the pelvis of an object, and an imaging unit measuring at least the front and sides of the object. capturing a plurality of images including, and having the sensor measure posture information simultaneously with the imaging; determining, by a control unit, an anterior pelvic plane based on the image of the object; and determining, by the control unit, an anterior pelvic plane based on the image of the object. Defining a local coordinate system based on the image and posture information, registering the local coordinate system of the sensor and the local coordinate system of the anterior pelvic plane by the control unit, and registering the local coordinate system of the anterior pelvic plane by the control unit, and position information measured by the sensor in real time. Based on this, determining the direction of the anterior pelvic plane.

In the three-dimensional real-time measurement method of the anterior pelvic plane according to an embodiment of the present invention, the imaging unit determines both ends of the horizontal bar and both ends of the vertical bar of the sensor attached to the pelvis and the anterior pelvic plane in the image. The image can be captured to show the dog's anatomical landmarks: right anterior superior iliac spine (R-ASIS), left anterior superior iliac spine (L-ASIS), and midpoint of the pubic tubercles (MPT).

In the three-dimensional real-time measurement method of the anterior pelvic plane according to an embodiment of the present invention, the step of measuring the posture information includes using the sensor as a 6-axis inertial measurement device to measure the posture information using Euler angles (roll, pitch, and yaw). ), and the control unit may further include defining a local coordinate system having the x-axis as the direction from one end of the horizontal bar to the other end of the horizontal bar and the z-axis as the direction from one end to the other end of the vertical bar based on the posture information. .

In the three-dimensional real-time measurement method of the anterior pelvic plane according to an embodiment of the present invention, the step of defining the local coordinate system includes the control unit displaying the local coordinate system as a three-dimensional vector and normalizing it to determine the local coordinate system. It is possible to calculate a matrix whose column vectors are regular orthogonal basis vectors that represent posture information in three dimensions. Here, the normal orthogonal basis and matrix are expressed as follows.

In the three-dimensional real-time measurement method of the anterior pelvic plane according to an embodiment of the present invention, the step of matching the local coordinate system of the sensor and the local coordinate system of the anterior pelvic plane includes the local coordinate system of the sensor and the local coordinate system of the sensor based on the image. determining one or more reference points for registering a local coordinate system of the anterior pelvic plane, determining a local coordinate system of the sensor and a local coordinate system of the anterior pelvic plane based on the reference points, and the determined local coordinate system of the sensor and the It may include registering a local coordinate system of the anterior pelvic plane.

In the three-dimensional real-time measurement method of the anterior pelvic plane according to an embodiment of the present invention, the step of determining the reference point includes determining both ends of the vertical bar, both ends of the horizontal bar, and the anterior pelvic plane displayed in the image. A step of numbering three anatomical points as reference points and measuring the distance from a preset origin in the image to the numbered plurality of reference points in pixel units, and the local coordinate system of the sensor and the anterior pelvic plane. Determining a local coordinate system may include calculating a vector defining a local coordinate system of the sensor and a local coordinate system of the anterior pelvic plane based on the distance from the origin to the plurality of reference points.

In the three-dimensional real-time measurement method of the anterior pelvic plane according to an embodiment of the present invention, the numbering step determines the top and bottom of the vertical bar, the left and right ends of the horizontal bar, and the anterior pelvic plane. The three anatomical points L-ASIS, MPT, and R-ASIS are numbered as P1 to P7, respectively, and the step of measuring in pixel units is performed at the origin O _F of the frontal image and the origin O _S of the side image. Measure the distance to the reference point in pixels, and measure the horizontal and vertical distances from the origin O _F , respectively. , It is expressed as , and the horizontal distance and vertical distance from the origin O _S are respectively , In the step of determining the local coordinate system of the sensor and the local coordinate system of the anterior pelvic plane, the height difference between both ends of the vertical bar in the image is set as a unit length, and the distance between the origin and the plurality of reference points is calculated as the unit length. The direction component of the vector between the plurality of reference points can be determined by dividing by the unit length. here is the horizontal pixel of the frontal image, is the vertical pixel of the frontal image, is the horizontal pixel of the side image, represents the vertical pixel of the side image, is a natural number from 1 to 7.

In the three-dimensional real-time measurement method of the anterior pelvic plane according to an embodiment of the present invention, the step of determining the local coordinate system of the sensor and the local coordinate system of the anterior pelvic plane is determined by measuring the height difference in the frontal image. , height difference between side images Calculate each, and based on this, the vector between the reference points , from which two vectors define the local coordinate system of the sensor. , and two vectors defining the local coordinate system of the anterior pelvic plane. , can be decided.

In the real-time measurement method for the three-dimensional orientation of the anterior pelvic plane according to an embodiment of the present invention, the step of determining the local coordinate system of the sensor and the local coordinate system of the anterior pelvic plane is a normal orthogonal coordinate system representing the three-dimensional sensor direction of the sensor. As a basis , , Calculate as a 3×3 matrix with the normal orthogonal basis vector as the column vector. , and as a vector determining the local coordinate system of the anterior pelvic plane, , , Calculating and matching the determined local coordinate system of the sensor and the local coordinate system of the anterior pelvic plane is and Matching the local coordinate system of the sensor in the image with the three-dimensional space based on It may include matching a local coordinate system of the sensor in the image with a local coordinate system of the anterior pelvic plane based on .

In the three-dimensional real-time measurement method of the anterior pelvic plane according to an embodiment of the present invention, the step of determining the direction of the anterior pelvic plane is based on the posture information of the sensor measured in real time by the sensor. Normal orthogonal basis representing 3D orientation Calculate and from this, as a 3×3 matrix with the normal orthogonal basis vector as the column vector, is defined, and from this, the latitude and longitude of the vector representing the normal direction of the anterior pelvic plane and the vector representing the direction of the anatomical point that determines the anterior pelvic plane can be determined.

A three-dimensional real-time measurement device for the anterior pelvic plane according to an embodiment of the present invention includes an imaging unit that captures an image of an object, a sensor and a control unit attached to the object to measure posture information, and the imaging unit is configured to capture an image of the object. A plurality of images including the front and sides of the sensor are captured, the sensor has a horizontal bar and a vertical bar extending from the center, and is attached to the rear of the pelvis of the object, and the image capture unit captures the image and simultaneously captures the posture information. Measures, and the control unit determines the anterior pelvic plane based on the image of the object, defines a local coordinate system based on the image and posture information of the object, and defines a local coordinate system of the sensor and a local coordinate system of the anterior pelvic plane. and determine the direction of the anterior pelvic plane based on the posture information measured by the sensor in real time.

In the three-dimensional real-time measurement device for the anterior pelvic plane according to an embodiment of the present invention, the imaging unit determines both ends of the horizontal bar and both ends of the vertical bar of the sensor attached to the pelvis and the anterior pelvic plane in the image. The image can be captured to identify the dog's anatomical points R-ASIS, L-ASIS, and MPT.

In the three-dimensional real-time measurement device for the anterior pelvic plane according to an embodiment of the present invention, the sensor is a 6-axis inertial measurement device that displays the posture information in Euler angles (roll, pitch, and yaw), and the control unit Based on the posture information, a local coordinate system can be defined in which the x-axis is the direction from one end of the horizontal bar to the other end, and the z-axis is the direction from one end to the other end of the vertical bar.

In the real-time measurement device for 3D orientation of the anterior pelvic plane according to an embodiment of the present invention, the control unit displays the local coordinate system as a 3D vector and normalizes it to form a normal orthogonal basis vector representing the posture information in 3D. You can calculate a matrix with as a column vector. Here, the normal orthogonal basis and matrix are expressed as follows.

In the three-dimensional real-time measurement device of the anterior pelvic plane according to an embodiment of the present invention, the control unit sets one or more reference points for matching the local coordinate system of the sensor and the local coordinate system of the anterior pelvic plane based on the image. and determine a local coordinate system of the sensor and a local coordinate system of the anterior pelvic plane based on the reference point, and match the determined local coordinate system of the sensor and the local coordinate system of the anterior pelvic plane.

In the three-dimensional real-time measurement device for the anterior pelvic plane according to an embodiment of the present invention, the control unit determines both ends of the vertical bar, both ends of the horizontal bar, and the anterior pelvic plane displayed in the image. Numbering a point as a reference point, measuring the distance from a preset origin in the image to the plurality of numbered reference points in pixel units, and determining a local coordinate system of the sensor and a local coordinate system of the anterior pelvic plane include the origin A vector defining a local coordinate system of the sensor and a local coordinate system of the anterior pelvic plane may be calculated based on the distances from the plurality of reference points.

In the three-dimensional real-time measurement device for the anterior pelvic plane according to an embodiment of the present invention, the control unit determines the upper and lower ends of the vertical bar, the left and right ends of the horizontal bar, and the anterior pelvic plane. The dog's anatomical points L-ASIS, MPT, and R-ASIS are numbered as P1 to P7, respectively, and the distance from the origin O _F of the frontal image and the origin O _S of the side image to the plurality of reference points is measured in pixels, , the horizontal distance and vertical distance from the origin O _F , respectively. , It is expressed as , and the horizontal distance and vertical distance from the origin O _S are respectively , It is expressed as , and the height difference between both ends of the vertical bar in the image is taken as a unit length, and the distance between the origin and the plurality of reference points is divided by the unit length to determine the direction component of the vector between the plurality of reference points. here is the horizontal pixel of the frontal image, is the vertical pixel of the frontal image, is the horizontal pixel of the side image, represents the vertical pixel of the side image, is a natural number from 1 to 7.

In the real-time measurement device for the three-dimensional direction of the anterior pelvic plane according to an embodiment of the present invention, the control unit measures the height difference in the frontal image. , height difference between side images Calculate each, and based on this, the vector between the reference points , from which two vectors define the local coordinate system of the sensor. , and two vectors defining the local coordinate system of the anterior pelvic plane. , can be decided.

In the real-time measuring device for the three-dimensional direction of the anterior pelvic plane according to an embodiment of the present invention, the control unit uses a regular orthogonal basis indicating the three-dimensional sensor direction of the sensor. , , Calculate as a 3×3 matrix with the normal orthogonal basis vector as the column vector. , and as a vector determining the local coordinate system of the anterior pelvic plane, , , Calculate and Based on , match the local coordinate system of the sensor in the three-dimensional space and the image, Based on this, the local coordinate system of the sensor in the image can be matched with the local coordinate system of the anterior pelvic plane.

In the real-time measurement device for the three-dimensional direction of the anterior pelvic plane according to an embodiment of the present invention, the control unit generates a regular orthogonal basis indicating the three-dimensional direction of the sensor based on the posture information of the sensor that the sensor measures in real time. Calculate and from this, as a 3×3 matrix with the normal orthogonal basis vector as the column vector, is defined, and from this, the latitude and longitude of the vector representing the normal direction of the anterior pelvic plane and the vector representing the direction of the anatomical point that determines the anterior pelvic plane can be determined.

Other aspects, features and advantages in addition to those described above will become apparent from the following drawings, claims and detailed description of the invention.

An apparatus and method for real-time measuring the three-dimensional direction of the anterior pelvic plane according to an embodiment of the present invention matches the local coordinate system of the sensor and the anterior pelvic plane, and generates a vector representing the direction of the anterior pelvic plane in real time even if the posture of the object changes. Can be printed. Through this, it is possible to implement a dynamic three-dimensional anterior pelvic plane direction measurement technology that is not limited to a specific posture.

1 shows a three-dimensional real-time measurement device for the anterior pelvic plane according to an embodiment of the present invention.
Figure 2 shows a method for real-time measuring the three-dimensional direction of the anterior pelvic plane according to an embodiment of the present invention.
Figure 3 shows a frontal image of an object according to an embodiment of the present invention.
Figure 4 shows a side image of an object according to an embodiment of the present invention.
Figure 5 shows latitude and longitude in a coordinate system according to an embodiment of the present invention.
6 and 7 show vectors determining the direction of the anterior pelvic plane calculated according to an embodiment of the present invention.

Since the present invention can be modified in various ways and can have various embodiments, specific embodiments will be illustrated in the drawings and described in detail in the description of the invention. However, this is not intended to limit the present invention to specific embodiments, and should be understood to include all transformations, equivalents, and substitutes included in the spirit and technical scope of the present invention. In explaining the present invention, even if it is shown in one embodiment, the same identification numbers are used for the same components.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. When describing with reference to the drawings, identical or corresponding components will be assigned the same reference numerals and redundant description thereof will be omitted. .

In the following embodiments, terms such as first and second are used not in a limiting sense but for the purpose of distinguishing one component from another component.

In the following examples, singular terms include plural terms unless the context clearly dictates otherwise.

In the following embodiments, terms such as include or have mean that the features or components described in the specification exist, and do not exclude in advance the possibility of adding one or more other features or components.

In the drawings, the sizes of components may be exaggerated or reduced for convenience of explanation. For example, the size and thickness of each component shown in the drawings are shown arbitrarily for convenience of explanation, so the present invention is not necessarily limited to what is shown.

In the following embodiments, the x-axis, y-axis, and z-axis are not limited to the three axes in the Cartesian coordinate system, but can be interpreted in a broad sense including these. For example, the x-axis, y-axis, and z-axis may be orthogonal to each other, but may also refer to different directions that are not orthogonal to each other.

In cases where an embodiment can be implemented differently, a specific process sequence may be performed differently from the described sequence. For example, two processes described in succession may be performed substantially at the same time, or may be performed in an order opposite to that in which they are described.

Figure 1 shows a real-time measuring device 1 for the three-dimensional direction of the anterior pelvic plane according to an embodiment of the present invention, and Figure 2 shows a method for real-time measuring the three-dimensional direction of the anterior pelvic plane according to an embodiment of the present invention. , FIG. 3 shows a frontal image of the object S according to an embodiment of the present invention, FIG. 4 shows a side image of the object S according to an embodiment of the present invention, and FIG. 5 shows an image of the object S according to an embodiment of the present invention. Shows latitude and longitude in a coordinate system according to an embodiment, and Figures 6 and 7 show a vector that determines the direction of the front tilt plane calculated according to an embodiment of the present invention.

A method and device for real-time measurement of the three-dimensional direction of the anterior pelvic plane (APP) (1, hereinafter also referred to as 'real-time measurement method and device') according to an embodiment of the present invention is used in performing artificial hip joint surgery, etc. It can be used to measure the three-dimensional direction of the anterior pelvic plane in real time, which is used as an evaluation index.

The anterior pelvic plane can be determined as a plane passing through three anatomical landmarks: right anterior superior iliac spine (R-ASIS), left anterior superior iliac spine (L-ASIS), and midpoint of the pubic tubercles (MPT). . For example, the anterior pelvic plane may be shown as a yellow plane that passes through the two ASIS and MPT.

The real-time measurement device 1 according to an embodiment of the present invention includes an imaging unit 10, a sensor 20, and a control unit 30.

The imaging unit 10 can capture an image of the object S. Here, the object (S) is not particularly limited and may be a human or an animal. The imaging unit 10 is a device that captures medical images and may be an X-ray device or a CT or MRI device. Hereinafter, for convenience of explanation, the description will focus on the case where the imaging unit 10 captures an X-ray image of a subject S, which is a patient. The imaging unit 10 may capture a plurality of images including a front image and a side image of the object S. Here, the object S is in a neutral standing posture, and the imaging unit 10 can capture an image in this state.

In one embodiment, the imaging unit 10 includes both ends of the vertical bar 21 of the sensor 20 attached to the pelvis in the image, both ends of the horizontal bar 23, and three anatomical points R-ASIS that determine the anterior pelvic plane. , images can be captured so that L-ASIS and MPT appear.

The sensor 20 is attached to the object S and can detect posture information in real time. For example, the sensor 20 may be attached to one side of the rear pelvis of the object S. In one embodiment, the sensor 20 may be a sensor that uses an inertial measurement unit (IMU). The sensor 20 includes one or more accelerometers and one or more gyro sensors, and thus can measure the posture of the object S, more specifically the roll, pitch, and yaw inclination, in real time.

In one embodiment, the sensor 20 may be a 6-axis sensor including a 3-axis accelerometer and a 3-axis gyro sensor. Additionally, the sensor 20 can display the attitude information as Euler angles: roll, pitch, and yaw, respectively, in ZYX order.

In one embodiment, the sensor 20 may include a bar 21 extending in a horizontal direction and a bar 23 extending in a vertical direction. As shown in FIG. 1, the vertical bar 21 and the horizontal bar 23 may intersect each other perpendicularly and be placed on the sensor 20 in the shape of a cross. In one embodiment, the vertical bar 21 and the horizontal bar 23 may each extend from the center of the sensor 20 by the same or different lengths.

In one embodiment, metal points may be disposed on one end (21a) and the other end (21b) of the vertical bar 21 and on one end (23a) and the other end (23b) of the horizontal bar 23, respectively. As shown in FIG. 1, each metal point may be disposed at both ends of the center line of the vertical bar 21 and the horizontal bar 23, respectively. Accordingly, when the imaging unit 10 captures an image, the position of the sensor 20 can be accurately confirmed in the image. Here, one end (21a) and the other end (21b) of the vertical bar 21 may be the upper and lower ends, respectively, and one end (23a) and the other end (23b) of the horizontal bar 23 may be the left end and the right end, respectively.

In one embodiment, the sensor 20 may measure posture information of the object S when the imaging unit 10 captures an image. That is, the sensor 20 can transmit the posture information of the object S to the control unit 30 at the same time that the imaging unit 10 captures the image of the object S. Accordingly, the control unit 30 can determine the direction of the anterior pelvic plane by matching the image captured by the imaging unit 10 with the posture information of the object S.

The control unit 30 can control the imaging unit 10 and the sensor 20 and perform calculations necessary to determine the direction of the anterior pelvic plane based on the image and posture information. For example, as shown in FIG. 1, the control unit 30 may include a display module 31, a communication module 33, a calculation module 35, an input module 37, and a storage module 39. The display module 31 visually displays images captured by the imaging unit 10, and the communication module 33 can communicate with the imaging unit 10, the sensor 20, and other external devices. Additionally, the calculation module 35 may perform calculations necessary to determine the direction of the anterior pelvic plane. In addition, the user can input necessary information into the control unit 30 through the input module 37 such as a keyboard, mouse, touch pad, etc., and the storage module 39 provides information necessary for the operation of the control unit 30 and input by the user. Information can be stored.

In one embodiment, the control unit 30 may be included in an electronic device such as a user's smartphone, tablet, laptop, or desktop. Alternatively, the control unit 30 may be included in a server, etc., and may deliver calculation results to the user. Through this, the user can check the image captured by the imaging unit 10 and the posture information detected by the sensor 20 in real time using an electronic device, and check the calculation results of the control unit 30. Additionally, the user can control the imaging unit 10 and sensor 20 through the control unit 30.

In one embodiment, the control unit 30 may determine the anterior pelvic plane based on the image of the object S captured by the imaging unit 10. As previously described, the anterior pelvic plane is determined by three anatomical points R-ASIS, L-ASIS, and MPT, and the control unit 30 receives the image from the imaging unit 10 and determines the three anatomical points therefrom. You can.

In one embodiment, the control unit 30 may determine three anatomical points from the image according to a predetermined algorithm and determine the anterior pelvic plane through these. For example, the control unit 30 controls three anatomies based on information about the object S (age, gender, height, weight, whether surgery has been performed) that is pre-stored or input by the user, as well as differences in brightness and shading that appear in the image. point can be determined. And the control unit 30 can determine the anterior pelvic plane connecting the three anatomical points. For example, the anterior pelvic plane is a plane connecting three anatomical points identified in the image, and can be expressed as a plane equation.

Additionally, the control unit 30 may define each local coordinate system based on the image and posture information of the object S. For example, the sensor 20 displays posture information in Euler angles, and the control unit 30 moves from one end 23a to the other end 23b of the horizontal bar 23 of the sensor 20 based on this posture information. A local coordinate system can be defined in which the x-axis is the direction and the z-axis is the direction from one end 21a of the vertical bar 21 to the other end 21b. Here, one end (21a) and the other end (21b) of the vertical bar 21 may be the upper and lower ends, respectively, and one end (23a) and the other end (23b) of the horizontal bar 23 may be the left end and the right end, respectively.

And the control unit 30 displays the local coordinate system defined in this way as a three-dimensional vector and normalizes it to form a normal orthogonal basis representing the three-dimensional direction of the sensor 20 obtained from the posture information of the sensor 20. can be obtained. And the control unit 30 is a 3×3 matrix with the normal orthogonal basis vector as the column vector. Calculate .

In one embodiment, the control unit 30 may match the local coordinate system of the sensor 20 and the local coordinate system of the anterior pelvic plane based on the calculated local coordinate system.

For example, the control unit 30 may determine one or more reference points for matching the local coordinate system of the sensor 20 and the local coordinate system of the anterior pelvic plane based on the image captured by the imaging unit 10. Additionally, the controller 30 may determine the local coordinate system of the sensor 20 and the local coordinate system of the anterior pelvic plane based on the determined reference point. And the control unit 30 may match the determined local coordinate system of the sensor 20 and the local coordinate system of the anterior pelvic plane.

For example, the control unit 30 controls both ends 21a, 21b of the vertical bar 21 and both ends 23a, 23b of the horizontal bar 23 displayed in the image of the object S, and 3 that determines the anterior pelvic plane. Dog anatomical points can be numbered as reference points. More specifically, as shown in FIGS. 6 and 7, the control unit 30 controls the top 21a and bottom 21b of the vertical bar 21 and the horizontal bar 23 in the front and side images of the object S. ) of the left end (23a) and right end (23b), the three anatomical points L-ASIS, MPT, and R-ASIS that determine the anterior pelvic plane, respectively, can be numbered in order from P1 to P7 to set the reference point. .

Additionally, the control unit 30 can set the origin in the image. For example, as shown in FIG. 6, the control unit 30 may set a point located in the upper left corner of the frontal image of the object S as the origin O _F. Additionally, as shown in FIG. 7 , the control unit 30 may set a point located in the upper left corner of the side image of the object S as the origin O _S. However, the origin of the image is not necessarily limited to the point located in the upper left corner, and any location that can serve as a reference is sufficient.

And the control unit 30 can measure the distance from the set origin to a plurality of numbered reference points. For example, the control unit 30 can measure the distance from the origin (O _S and O _F ) to the reference points P1 to P7 in pixel units using image software, etc. In addition, the control unit 30 determines the horizontal distance and vertical distance from the origin (O _F ) to the plurality of reference points, respectively. , It can be expressed as In addition, the control unit 30 determines the horizontal distance and vertical distance from the origin ( _OS ) to a plurality of reference points, respectively. , It can be expressed as here represents the number of the reference point and is a natural number from 1 to 7.

And the control unit 30 can use the measured distance from the origin and the reference point to calculate a vector defining the local coordinate system of the sensor 20 and a vector defining the anterior pelvic plane. More specifically, the control unit 30 sets the height difference between the ends 21a and 21b of the vertical bar 21 in the image as a unit length. That is, the height difference between the reference points P1 and P2 is the same in the front and side images of the object (S), so the height difference in the front Height difference from the side

has the same length. Using this, the control unit 30 and is defined as the unit length in the front and side images.

Additionally, the control unit 30 can determine the direction components of vectors between a plurality of reference points by dividing the length from the origin and the reference point by the unit length obtained above. More specifically, the control unit 30 calculates the x component of the vector by dividing the length obtained in pixels in the front image by the unit length UF, and the y component by dividing the length obtained in pixels in the side image by the unit length US. Since the z component can be calculated from both the front image and the side image, the control unit 30 determines it as the average of the z component in the front image and the side image. Accordingly, the control unit 30 can determine the direction component of the vector between reference points using the following equation.

Here, P _i and P _j represent reference points, respectively, and UF and US represent the unit length in the frontal image and the unit length in the side image.

Next, the control unit 30 uses the above equation to define two vectors that define the local coordinate system of the sensor 20. , and two vectors defining the local coordinate system of the anterior pelvic plane. , decide. And the control unit 30 uses the calculated vector as a regular orthogonal basis representing the three-dimensional sensor direction of the sensor 20. , , Calculate as a 3×3 matrix with the normal orthogonal basis vector as the column vector. Define. In addition, the control unit 30 serves as a vector for determining the local coordinate system of the anterior pelvic plane. , , By calculating , the local coordinate system of the sensor 20 and the local coordinate system of the anterior pelvic plane are determined. here and are a vector representing the direction from L-ASIS to R-ASIS, which determines the anterior pelvic plane, and a vector representing the normal direction of the anterior pelvic plane, respectively. In other words and is a vector that determines the local coordinate system of the anterior pelvic plane when the object S is standing, and may be a reference coordinate system for estimating the local coordinate system of the anterior pelvic plane in other postures.

And the control unit 30 can register the local coordinate system of the sensor 20 determined in this way and the local coordinate system of the anterior pelvic plane. That is, the control unit 30 associates different coordinate systems with each other and calculates the relationship of how other coordinate systems change when one coordinate system changes, thereby maintaining the local coordinate system of the anterior pelvic plane even if the posture of the object S changes. It is possible to make continuous estimates.

First, the control unit 30 can define latitude and longitude, respectively, to indicate the normal vector direction of the anterior pelvic plane using latitude and longitude. For example, as shown in FIG. 5, the control unit 30 controls latitude in three-dimensional space. The vector on the xy plane is defined as 0 degrees, the z direction is defined as 90 degrees, and the -z direction is defined as -90 degrees. In addition, the control unit 30 has hardness The vector on the zx plane is defined as 0 degrees, the y direction is defined as 90 degrees, and the -x direction is defined as 180 degrees.

And the control unit 30 calculates the above and Based on this, the local coordinate system of the sensor 20 in the three-dimensional space and the image is matched. That is, the control unit 30 uses the normal orthogonal basis vector of the sensor 20 in the three-dimensional space as a column vector, and based on the local coordinate system of the sensor 20 obtained from the image, The local coordinate system of the sensor 20 can be matched.

Additionally, the control unit 30 operates in the local coordinate system of the sensor 20 in the image. and a vector determining the local coordinate system of the anterior pelvic plane. and It is possible to match the local coordinate system of the sensor 20 in the image with the local coordinate system of the anterior pelvic plane.

Through this, the control unit 30 determines the local coordinate system of the sensor 20 in the three-dimensional space and the image, matches the local coordinate system of the sensor 20 in the image with the local coordinate system of the anterior pelvic plane, and The local coordinate system of the sensor 20 and the local coordinate system of the anterior pelvic plane in the image can be matched.

And the control unit 30 may determine the direction of the anterior pelvic plane based on the posture information measured in real time by the sensor 20. More specifically, when registration of the local coordinate system is completed, the sensor 20 can measure posture information in real time while attached to the object S. In addition, similar to the method described above, the control unit 30 uses the Euler angles (roll, pitch, yaw) in the ZYX order output from the sensor 20 from the left end 23a to the right end 23b of the horizontal bar 23. ) as the x-axis and the local coordinate system with the lower end (21b) to the upper end (21a) of the vertical bar 21 as the z-axis can be expressed as a three-dimensional vector. Then, the control unit 30 normalizes these three-dimensional vectors to form a normal orthogonal basis representing the three-dimensional direction of the sensor 20 based on the posture information of the sensor 20. Calculate as a 3×3 matrix with the basis vector as the column vector. Define. here may indicate a state in which the object S has changed its posture.

In addition, the control unit 30 reconstructs the posture information from the sensor 20 when the object S changes its posture. Using , the vector representing the normal direction of the anterior pelvic plane in the new posture of the object (S) and the vector representing the direction from L-ASIS to R-ASIS of the anterior pelvic plane can be calculated as follows.

And the control unit 30 is a vector representing the normal direction of the anterior pelvic plane. A vector representing the direction from L-ASIS to R-ASIS, which determines the latitude and longitude of the anterior pelvic plane. The latitude and longitude can be output.

For example, Figures 6 and 7 show both ends 21a and 21b of the vertical bar 21 and both ends of the horizontal bar 23 of the sensor 20 attached to the pelvis, with the subject S in a posture bent forward 30 degrees. (23a, 23b) and images taken from the front and lateral (left side) views of the three anatomical points that determine the anterior pelvic plane.

In one embodiment, the control unit 30 may be implemented in the form of an application on a smartphone or tablet.

Next, with reference to FIGS. 1 to 7 , a method for real-time measuring the three-dimensional direction of the anterior pelvic plane according to an embodiment of the present invention will be described.

The three-dimensional real-time measurement method of the anterior pelvic plane according to an embodiment of the present invention includes attaching a sensor 20 to the pelvis of an object S, and the imaging unit 10 measuring the front and sides of the object S. A step of capturing a plurality of images including, a step of the sensor 20 measuring posture information, a step of the control unit 30 determining the anterior pelvic plane based on the image of the object S, and the control unit 30 determining the anterior pelvic plane based on the image of the object S. A step of defining a local coordinate system based on the image and posture information of (S), a step of the control unit 30 matching the local coordinate system of the sensor 20 and the local coordinate system of the anterior pelvic plane, and the control unit 30 matching the local coordinate system of the sensor 20 ) may include determining the direction of the anterior pelvic plane based on posture information measured in real time.

First, the sensor 20 is attached to the rear of the pelvis of the object S. Here, the sensor 20 may include a vertical bar 21 and a horizontal bar 23 extending from the center.

Next, the imaging unit 10 captures a plurality of images of the object S. Here, the object S may be standing upright, and at least a frontal image and a side image of the object S can be captured. In one embodiment, the imaging unit 10 detects both ends 21a, 21b of the vertical bar 21 of the sensor 20 attached to the pelvis, both ends 23a, 23b of the horizontal bar 23, and the front of the captured image. Images can be taken to show three anatomical points that determine the pelvic plane.

Next, the sensor 20 measures posture information. In one embodiment, the sensor 20 may measure posture information at the same time that the imaging unit 10 captures an image. In addition, the imaging unit 10 and the sensor 20 can transmit the captured image and the measured posture information to the control unit 30. In one embodiment, the sensor 20 is a 6-axis inertial measurement device, and can represent posture information in Euler angles.

Next, the control unit 30 defines a local coordinate system based on the image and posture information of the object S. In one embodiment, the control unit 30 determines the direction from the left end 23a to the right end 23b of the horizontal bar 23 based on the posture information measured by the sensor 20 along the x-axis and the vertical bar 21. It may further include defining a local coordinate system having the z-axis in a direction from the lower end 21b to the upper end 21a.

In one embodiment, in the step of defining a local coordinate system, the control unit 30 displays the local coordinate system as a 3-dimensional vector, normalizes it, and calculates a matrix with a regular orthogonal basis vector representing posture information in 3 dimensions as a column vector. . Here, the normal orthogonal basis and matrix are expressed as follows. , .

Next, the control unit 30 matches the local coordinate system of the sensor 20 and the local coordinate system of the anterior pelvic plane. In one embodiment, the step of matching the local coordinate system includes determining one or more reference points for matching the local coordinate system of the sensor 20 and the local coordinate system of the anterior pelvic plane based on the image, and determining one or more reference points of the sensor 20 based on the reference point. It may include determining a local coordinate system and a local coordinate system of the anterior pelvic plane, and matching the determined local coordinate system of the sensor 20 and the local coordinate system of the anterior pelvic plane.

In one embodiment, the step of determining the reference point includes both ends 21a and 21b of the vertical bar 21 shown in the image, both ends 23a and 23b of the horizontal bar 23, and three anatomical points that determine the anterior pelvic plane. It may include numbering as a reference point and measuring the distance from a preset origin in the image to a plurality of numbered reference points in pixel units.

In one embodiment, the step of determining the local coordinate system of the sensor 20 and the local coordinate system of the anterior pelvic plane defines the local coordinate system of the sensor 20 and the local coordinate system of the anterior pelvic plane based on the distances from the origin to a plurality of reference points. The vector can be calculated.

In one embodiment, the numbering steps include the top (21a) and bottom (21b) of the vertical bar (21), the left end (23a) and right end (23b) of the horizontal bar (23), and three steps that determine the anterior pelvic plane. Anatomical points L-ASIS, MPT, and R-ASIS can be numbered P1 to P7, respectively.

In one embodiment, the step of measuring in pixels measures the distance from the origin O _F of the frontal image and the origin O _S of the side image to a plurality of reference points in pixel units, and the horizontal distance and vertical distance from the origin O _F respectively , It is expressed as , and the horizontal distance and vertical distance from the origin O _S are respectively , It can be expressed as here is the horizontal pixel of the frontal image, is the vertical pixel of the frontal image, is the horizontal pixel of the side image, represents the vertical pixel of the side image, is a natural number from 1 to 7.

In one embodiment, the step of determining the local coordinate system of the sensor 20 and the local coordinate system of the anterior pelvic plane uses the height difference between the ends 21a and 21b of the vertical bar 21 in the image as a unit length, and determines the origin and plurality of The direction component of the vector between a plurality of reference points can be determined by dividing the distance to the reference points by the unit length.

In one embodiment, the step of determining the local coordinate system of the sensor 20 and the local coordinate system of the anterior pelvic plane is the height difference in the frontal image. , height difference between side images Calculate each, and based on this, the vector between the reference points

Calculate , from which two vectors define the local coordinate system of the sensor 20 , and two vectors defining the local coordinate system of the anterior pelvic plane. , can be decided.

In one embodiment, the step of determining the local coordinate system of the sensor 20 and the local coordinate system of the anterior pelvic plane is a normal orthogonal basis representing the three-dimensional sensor orientation of the sensor 20. , , Calculate as a 3×3 matrix with the normal orthogonal basis vector as the column vector. , and as a vector determining the local coordinate system of the anterior pelvic plane, , , can be calculated.

The step of matching the local coordinate system of the sensor 20 determined in one embodiment and the local coordinate system of the anterior pelvic plane is and A step of matching the local coordinate system of the sensor 20 in the three-dimensional space and the image based on It may include matching the local coordinate system of the sensor 20 in the image with the local coordinate system of the anterior pelvic plane based on .

In one embodiment, before the step of matching the local coordinate system, the control unit 30 may further include a step of defining latitude and longitude, respectively, to indicate the normal vector direction of the anterior pelvic plane using the latitude and longitude. The control unit 30 controls latitude in three-dimensional space.

The vector on the xy plane is defined as 0 degrees, the z direction is defined as 90 degrees, and the -z direction is defined as -90 degrees. In addition, the control unit 30 has hardness The vector on the zx plane can be defined as 0 degrees, the y direction as 90 degrees, and the -x direction as 180 degrees.

In one embodiment, the step of determining the direction of the anterior pelvic plane is performed by using a regular orthogonal basis representing the three-dimensional direction of the sensor 20 based on the posture information of the sensor 20 measured in real time by the sensor 20. Calculate and from this, as a 3×3 matrix with the normal orthogonal basis vector as the column vector. is defined, and from this, the latitude and longitude of the vector representing the normal direction of the anterior pelvic plane and the vector representing the direction of the anatomical point that determines the anterior pelvic plane can be determined.

In one embodiment may indicate a state in which the object S has changed its posture. In addition, the control unit 30 reconstructs the posture information of the sensor 20 when the object S changes its posture. Using , the vector representing the normal direction of the anterior pelvic plane in the new posture of the object (S) and the vector representing the direction from L-ASIS to R-ASIS of the anterior pelvic plane can be calculated as follows.

And the control unit 30 is a vector representing the normal direction of the anterior pelvic plane. A vector representing the direction from L-ASIS to R-ASIS, which determines the latitude and longitude of the anterior pelvic plane. The latitude and longitude can be output.

In this way, the real-time measuring device 1 and method for the three-dimensional direction of the anterior pelvic plane according to an embodiment of the present invention matches the local coordinate system of the sensor 20 and the anterior pelvic plane, even if the posture of the object S changes. A vector representing the direction of the anterior pelvic plane can be output in real time. Through this, it is possible to implement a dynamic three-dimensional anterior pelvic plane direction measurement technology that is not limited to a specific posture.

The device described above may be implemented with hardware components, software components, and/or a combination of hardware components and software components. For example, devices and components described in embodiments may include, for example, a processor, a controller, an arithmetic logic unit (ALU), a digital signal processor, a microcomputer, a field programmable gate array (FPGA), etc. , may be implemented using one or more general-purpose or special-purpose computers, such as a programmable logic unit (PLU), a microprocessor, or any other device capable of executing and responding to instructions. The processing device may execute an operating system (OS) and one or more software applications running on the operating system. Additionally, a processing device may access, store, manipulate, process, and generate data in response to the execution of software. For ease of understanding, a single processing device may be described as being used; however, those skilled in the art will understand that a processing device includes multiple processing elements and/or multiple types of processing elements. It can be seen that it may include. For example, a processing device may include a plurality of processors or one processor and one controller. Additionally, other processing configurations, such as parallel processors, are possible.

Software may include a computer program, code, instructions, or a combination of one or more of these, which may configure a processing unit to operate as desired, or may be processed independently or collectively. You can command the device. Software and/or data may be used on any type of machine, component, physical device, virtual equipment, computer storage medium or device to be interpreted by or to provide instructions or data to a processing device. , or may be permanently or temporarily embodied in a transmitted signal wave. Software may be distributed over networked computer systems and stored or executed in a distributed manner. Software and data may be stored on one or more computer-readable recording media.

The method according to the embodiment may be implemented in the form of program instructions that can be executed through various computer means and recorded on a computer-readable medium. The computer-readable medium may include program instructions, data files, data structures, etc., singly or in combination. Program instructions recorded on the medium may be specially designed and configured for the embodiment or may be known and available to those skilled in the art of computer software. Examples of computer-readable recording media include magnetic media such as hard disks, floppy disks, and magnetic tapes, optical media such as CD-ROMs and DVDs, and magnetic media such as floptical disks. -Includes optical media (magneto-optical media) and hardware devices specifically configured to store and execute program instructions, such as ROM, RAM, flash memory, etc. Examples of program instructions include machine language code, such as that produced by a compiler, as well as high-level language code that can be executed by a computer using an interpreter, etc. The hardware devices described above may be configured to operate as one or more software modules to perform the operations of the embodiments, and vice versa.

Although the present invention has been described with reference to the embodiments shown in the drawings, these are merely examples. Those skilled in the art can fully understand that various modifications and equivalent embodiments are possible from the examples. Therefore, the true technical protection scope of the present invention should be determined based on the attached claims.

The specific technical content described in the embodiment is an example and does not limit the technical scope of the embodiment. In order to describe the invention concisely and clearly, descriptions of conventional general techniques and configurations may be omitted. In addition, the connection of lines or the absence of connections between components shown in the drawings exemplify functional connections and/or physical or circuit connections, and in actual devices, various functional connections or physical connections may be replaced or added. It can be expressed as connections, or circuit connections. Additionally, if there is no specific mention such as “essential,” “important,” etc., it may not be a necessary component for the application of the present invention.

“The” or similar designators used in the description and claims may refer to both the singular and the plural, unless otherwise specified. In addition, when a range is described in an example, the invention includes the application of individual values within the range (unless there is a statement to the contrary), and each individual value constituting the range is described in the description of the invention. same. Additionally, unless the order of the steps constituting the method according to the embodiment is clearly stated or there is no description to the contrary, the steps may be performed in an appropriate order. The embodiments are not necessarily limited by the order of description of the above steps. The use of any examples or illustrative terms (e.g., etc.) in the embodiments is merely to describe the embodiments in detail, and unless limited by the claims, the examples or illustrative terms do not limit the scope of the embodiments. That is not the case. Additionally, those skilled in the art will appreciate that various modifications, combinations and changes may be made according to design conditions and factors within the scope of the appended claims or their equivalents.

1: Real-time measurement device for three-dimensional orientation of the anterior pelvic plane
10: imaging unit
20: sensor
21: vertical bar
23: horizontal bar
30: control unit
S: object

Claims (20)

Attaching a sensor with a horizontal bar and a vertical bar extending from the center to the rear of the pelvis of the object;
A step in which an imaging unit captures a plurality of images including at least the front and side surfaces of the object, and the sensor measures posture information simultaneously with the imaging;
A control unit determining an anterior pelvic plane based on the image of the object;
The control unit defining a local coordinate system based on the image and posture information of the object;
registering, by the control unit, a local coordinate system of the sensor and a local coordinate system of the anterior pelvic plane; and
A method for measuring the three-dimensional direction of the anterior pelvic plane in real time, including the step of the control unit determining the direction of the anterior pelvic plane based on posture information measured in real time by the sensor. According to claim 1,
The imaging unit includes R-ASIS (right anterior superior iliac spine) and L-ASIS (right anterior superior iliac spine) as three anatomical landmarks that determine both ends of the horizontal bar and the vertical bar of the sensor attached to the pelvis in the image and the anterior pelvic plane. A three-dimensional real-time measurement method of the anterior pelvic plane, in which the image is captured to reveal the left anterior superior iliac spine (ASIS) and the midpoint of the pubic tubercles (MPT). According to claim 1,
In the step of measuring the posture information, the sensor is a 6-axis inertial measurement device and represents the posture information in Euler angles (roll, pitch, and yaw),
3 in the anterior pelvic plane, further comprising the step of the control unit defining a local coordinate system having the x-axis as the direction from one end to the other end of the horizontal bar and the z-axis as the direction from one end to the other end of the vertical bar based on the posture information. Real-time measurement method for dimensional orientation. According to clause 3,
In the step of defining the local coordinate system, the control unit displays the local coordinate system as a three-dimensional vector, normalizes it, and calculates a matrix with a regular orthogonal basis vector representing the posture information in three dimensions as a column vector. A real-time measurement method for three-dimensional orientation in the anterior pelvic plane.
Here, the normal orthogonal basis and matrix are expressed as follows.

According to claim 1,
The step of matching the local coordinate system of the sensor and the local coordinate system of the anterior pelvic plane is
determining one or more reference points for registering a local coordinate system of the sensor and a local coordinate system of the anterior pelvic plane based on the image;
determining a local coordinate system of the sensor and a local coordinate system of the anterior pelvic plane based on the reference point; and
A method for real-time measuring three-dimensional orientation of the anterior pelvic plane, comprising: matching the determined local coordinate system of the sensor and the local coordinate system of the anterior pelvic plane. According to clause 5,
The step of determining the reference point is
Numbering three anatomical points that determine both ends of the vertical bar, both ends of the horizontal bar, and the anterior pelvic plane displayed in the image as reference points; and
A step of measuring the distance from a preset origin in the image to the plurality of numbered reference points in pixel units,
Determining the local coordinate system of the sensor and the local coordinate system of the anterior pelvic plane includes calculating a vector defining the local coordinate system of the sensor and the local coordinate system of the anterior pelvic plane based on the distances from the origin to the plurality of reference points. A real-time measurement method for three-dimensional orientation of the anterior pelvic plane. According to clause 6,
The numbering step involves numbering the three anatomical points L-ASIS, MPT, and R-ASIS that determine the top and bottom of the vertical bar, the left end and right end of the horizontal bar, and the anterior pelvic plane as P1 to P7, respectively. do,
The step of measuring in pixel units measures the distance from the origin O _F of the front image and the origin O _S of the side image to the plurality of reference points in pixel units, and the horizontal distance and vertical distance from the origin O _F respectively , It is expressed as , and the horizontal distance and vertical distance from the origin O _S are respectively , It is expressed as
The step of determining the local coordinate system of the sensor and the local coordinate system of the anterior pelvic plane is performed by using the height difference between both ends of the vertical bar in the image as a unit length, and using the distance between the origin and the plurality of reference points as the unit length. A three-dimensional real-time measurement method of the anterior pelvic plane that determines the direction components of the vector between the plurality of reference points by dividing them.
here is the horizontal pixel of the frontal image, is the vertical pixel of the frontal image, is the horizontal pixel of the side image, represents the vertical pixel of the side image, is a natural number from 1 to 7. According to clause 7,
Determining the local coordinate system of the sensor and the local coordinate system of the anterior pelvic plane includes the height difference in the frontal image. , height difference between side images Calculate each, and based on this, the vector between the reference points
, from which two vectors define the local coordinate system of the sensor. , and two vectors defining the local coordinate system of the anterior pelvic plane. , A real-time measurement method for three-dimensional orientation of the anterior pelvic plane, which determines . According to clause 8,
Determining a local coordinate system of the sensor and a local coordinate system of the anterior pelvic plane comprises
As a normal orthogonal basis representing the three-dimensional sensor direction of the sensor, , , Calculate as a 3×3 matrix with the normal orthogonal basis vector as the column vector. define,
As a vector determining the local coordinate system of the anterior pelvic plane , , Calculate
The step of matching the determined local coordinate system of the sensor and the local coordinate system of the anterior pelvic plane is
and Matching the local coordinate system of the sensor in the image with three-dimensional space based on; and
Registering a local coordinate system of the sensor in the image and a local coordinate system of the anterior pelvic plane based on a three-dimensional real-time measurement method of the anterior pelvic plane. According to claim 1,
Determining the direction of the anterior pelvic plane includes using a regular orthogonal basis representing the three-dimensional direction of the sensor based on the posture information of the sensor that the sensor measures in real time. Calculate and from this, as a 3×3 matrix with the normal orthogonal basis vector as the column vector, A method for real-time measuring the three-dimensional orientation of the anterior pelvic plane, wherein the latitude and longitude of the vector representing the normal direction of the anterior pelvic plane and the vector representing the direction of the anatomical point that determines the anterior pelvic plane are determined. It includes an imaging unit that captures an image of an object, a sensor that is attached to the object and measures posture information, and a control unit,
The imaging unit captures a plurality of images including the front and side surfaces of the object,
The sensor has a horizontal bar and a vertical bar extending from the center, is attached to the rear of the pelvis of the object, and the imaging unit captures an image and measures the posture information at the same time,
The control unit determines the anterior pelvic plane based on the image of the object, defines a local coordinate system based on the image and posture information of the object, and matches the local coordinate system of the sensor and the local coordinate system of the anterior pelvic plane, A real-time three-dimensional orientation measurement device for the anterior pelvic plane, which determines the direction of the anterior pelvic plane based on posture information measured in real time by the sensor. According to claim 11,
The imaging unit captures the image so that R-ASIS, L-ASIS, and MPT are confirmed as three anatomical points that determine both ends of the horizontal bar and the vertical bar of the sensor attached to the pelvis and the anterior pelvic plane in the image. , a real-time measurement device for three-dimensional orientation in the anterior pelvic plane. According to claim 11,
The sensor is a 6-axis inertial measurement device that displays the attitude information in Euler angles (roll, pitch, and yaw),
The control unit defines a local coordinate system having an x-axis as a direction from one end of the horizontal bar to the other end of the horizontal bar and a z-axis as a direction from one end of the vertical bar to the other end of the vertical bar based on the posture information. A three-dimensional real-time measurement device for the anterior pelvic plane. . According to claim 13,
The control unit displays the local coordinate system as a three-dimensional vector, normalizes it, and calculates a matrix with a column vector as a regular orthogonal basis vector representing the posture information in three dimensions.
Here, the normal orthogonal basis and matrix are expressed as follows.

According to claim 11,
The control unit determines one or more reference points for matching the local coordinate system of the sensor and the local coordinate system of the anterior pelvic plane based on the image, and the local coordinate system of the sensor and the local coordinate system of the anterior pelvic plane based on the reference point. A real-time measurement device for three-dimensional orientation of the anterior pelvic plane, determining and matching the determined local coordinate system of the sensor with the local coordinate system of the anterior pelvic plane. According to claim 15,
The control unit numbers both ends of the vertical bar, both ends of the horizontal bar, and three anatomical points that determine the anterior pelvic plane displayed in the image as reference points, from a preset origin in the image to the plurality of numbered reference points. The step of measuring the distance in pixels and determining the local coordinate system of the sensor and the local coordinate system of the anterior pelvic plane is based on the distance from the origin to the plurality of reference points. A real-time measurement device for three-dimensional orientation in the anterior pelvic plane, calculating vectors defining the local coordinate system of . According to claim 16,
The control unit numbers the three anatomical points L-ASIS, MPT, and R-ASIS that determine the top and bottom of the vertical bar, the left end and right end of the horizontal bar, and the anterior pelvic plane as P1 to P7, respectively, The distance from the origin O _F of the front image and the origin O _S of the side image to the plurality of reference points is measured in pixels, and the horizontal distance and vertical distance from the origin O _F are respectively , It is expressed as , and the horizontal distance and vertical distance from the origin O _S are respectively , It is expressed as , and the height difference between both ends of the vertical bar in the image is taken as a unit length, and the distance between the origin and the plurality of reference points is divided by the unit length to determine the direction component of the vector between the plurality of reference points. A real-time measurement device for three-dimensional orientation of the pelvic plane.
here is the horizontal pixel of the frontal image, is the vertical pixel of the frontal image, is the horizontal pixel of the side image, represents the vertical pixel of the side image, is a natural number from 1 to 7. According to claim 17,
The control unit determines the height difference in the front image , height difference between side images Calculate each, and based on this, the vector between the reference points
, from which two vectors define the local coordinate system of the sensor. , and two vectors defining the local coordinate system of the anterior pelvic plane. , A real-time measurement device for the three-dimensional orientation of the anterior pelvic plane, which determines. According to clause 18,
The control unit serves as a regular orthogonal basis representing the three-dimensional sensor direction of the sensor. , , Calculate as a 3×3 matrix with the normal orthogonal basis vector as the column vector. , and as a vector determining the local coordinate system of the anterior pelvic plane, , , Calculate and Based on , match the local coordinate system of the sensor in the three-dimensional space and the image, , A three-dimensional orientation real-time measurement device in the anterior pelvic plane, matching the local coordinate system of the sensor in the image with the local coordinate system of the anterior pelvic plane based on . According to claim 11,
The control unit uses a regular orthogonal basis indicating the three-dimensional direction of the sensor based on the posture information of the sensor that the sensor measures in real time. Calculate and from this, as a 3×3 matrix with the normal orthogonal basis vector as the column vector, A real-time measurement device for three-dimensional orientation of the anterior pelvic plane, wherein the latitude and longitude of the vector representing the normal direction of the anterior pelvic plane and the vector representing the direction of the anatomical point that determines the anterior pelvic plane are determined.

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