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CN111686378A - Bed body movement precision detection method, device, equipment and storage medium - Google Patents

Bed body movement precision detection method, device, equipment and storage medium Download PDF

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CN111686378A
CN111686378A CN202010677817.8A CN202010677817A CN111686378A CN 111686378 A CN111686378 A CN 111686378A CN 202010677817 A CN202010677817 A CN 202010677817A CN 111686378 A CN111686378 A CN 111686378A
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bed body
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bed
movement
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CN111686378B (en
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薛舟
师中华
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Shanghai United Imaging Healthcare Co Ltd
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    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61N—ELECTROTHERAPY; MAGNETOTHERAPY; RADIATION THERAPY; ULTRASOUND THERAPY
    • A61N5/00—Radiation therapy
    • A61N5/10—X-ray therapy; Gamma-ray therapy; Particle-irradiation therapy
    • A61N5/1048—Monitoring, verifying, controlling systems and methods
    • A61N5/1064—Monitoring, verifying, controlling systems and methods for adjusting radiation treatment in response to monitoring
    • A61N5/1069—Target adjustment, e.g. moving the patient support
    • A61N5/107—Target adjustment, e.g. moving the patient support in real time, i.e. during treatment
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    • G06—COMPUTING OR CALCULATING; COUNTING
    • G06T—IMAGE DATA PROCESSING OR GENERATION, IN GENERAL
    • G06T7/00—Image analysis
    • G06T7/20—Analysis of motion
    • G—PHYSICS
    • G06—COMPUTING OR CALCULATING; COUNTING
    • G06T—IMAGE DATA PROCESSING OR GENERATION, IN GENERAL
    • G06T7/00—Image analysis
    • G06T7/80—Analysis of captured images to determine intrinsic or extrinsic camera parameters, i.e. camera calibration
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61N—ELECTROTHERAPY; MAGNETOTHERAPY; RADIATION THERAPY; ULTRASOUND THERAPY
    • A61N5/00—Radiation therapy
    • A61N5/10—X-ray therapy; Gamma-ray therapy; Particle-irradiation therapy
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    • A61N2005/1097—Means for immobilizing the patient

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Abstract

The embodiment of the invention discloses a bed body movement precision detection method, a bed body movement precision detection device, bed body movement precision detection equipment and a storage medium, wherein the method comprises the following steps: acquiring at least two groups of first projection images for recording the start-stop position of the bed body in the current track motion; for each group of first projection images, respectively taking the first projection images corresponding to the starting point and the ending point of the bed body movement as reference projection images and comparison projection images; determining the variation of the position of the marker of the comparative projection image relative to the position of the marker of the reference projection image and the deviation of actual in-place data corresponding to the variation relative to corresponding expected in-place data, and taking the deviation as a single movement error of the bed body in corresponding movement on the current track; and determining the motion precision of the bed body in corresponding motion on the current track according to all single motion errors of the bed body. The method solves the problem that the prior method for detecting the bed body motion precision is difficult to meet the requirement of image-guided radiotherapy on the bed body motion precision.

Description

Bed body movement precision detection method, device, equipment and storage medium
Technical Field
The embodiment of the invention relates to the field of medical equipment, in particular to a bed body movement precision detection method, a bed body movement precision detection device, bed body movement precision detection equipment and a storage medium.
Background
Image-guided Radiotherapy (IGRT) has a very high requirement on the accuracy of the in-place movement of the accelerator bed, and therefore the in-place movement accuracy of the bed needs to be detected frequently, so that the in-place movement accuracy of the bed can be found and corrected in time when the in-place movement accuracy of the bed does not meet clinical requirements.
At present, the in-place movement precision measuring method of the bed body on each track needs mechanical equipment such as an angle ruler, a laser lamp or a dial indicator to be realized in an auxiliary mode, the mechanical equipment needs to be manually placed and adjusted in the measuring process, and measuring data of each mechanical equipment is manually read. Because the number of the manual participation links is large, the error of the measuring result is large, and the precision requirement of the image-guided radiotherapy on the movement precision of the bed body is difficult to meet.
In summary, the existing bed body movement precision detection method is difficult to meet the requirement of image-guided radiotherapy on the bed body movement precision.
Disclosure of Invention
The embodiment of the invention provides a bed body movement precision detection method, a bed body movement precision detection device, bed body movement precision detection equipment and a storage medium, and solves the problem that the requirements of image-guided radiotherapy on the bed body movement precision are difficult to meet in the existing bed body movement precision detection method.
In a first aspect, an embodiment of the present invention provides a bed motion precision detection method, including:
acquiring at least two groups of first projection images for recording the start-stop position of the bed body in the current orbital motion, wherein the first projection images comprise markers arranged in a mold body, the mold body is arranged above the bed body, the bed body moves in a one-way motion mode or a reciprocating motion mode, and the number of times of movement is more than or equal to two;
for each group of first projection images, taking the first projection image corresponding to the starting point of the bed body movement as a reference projection image, and taking the first projection image corresponding to the ending point of the bed body movement as a comparison projection image;
determining the variation of the position of the marker in the comparative projection image relative to the position of the marker in the reference projection image and the deviation of actual in-place data corresponding to the variation relative to corresponding expected in-place data, and taking the deviation as a single movement error of the corresponding movement of the bed body on the current track;
and determining the motion precision of the bed body in corresponding motion on the current track according to all single motion errors of the bed body.
In a second aspect, an embodiment of the present invention further provides a bed movement precision detection apparatus, including:
the device comprises an acquisition module, a display module and a control module, wherein the acquisition module is used for acquiring at least two groups of first projection images for recording the start-stop position of the bed body in the current orbital motion, the first projection images comprise markers arranged in a mold body, the mold body is arranged above the bed body, the motion mode of the bed body is one-way motion or reciprocating motion, and the motion times are more than or equal to two times;
the image grouping module is used for taking the first projection image corresponding to the starting point of the bed body movement as a reference projection image and taking the first projection image corresponding to the ending point of the bed body movement as a comparison projection image for each group of first projection images;
the movement error determining module is used for determining the variation of the position of the marker in the comparative projection image relative to the position of the marker in the reference projection image and the deviation of actual in-place data corresponding to the variation relative to corresponding expected in-place data, and taking the deviation as a single movement error of the bed body in corresponding movement on the current track;
and the motion precision determining module is used for determining the motion precision of the bed body in corresponding motion on the current track according to all single motion errors of the bed body.
In a third aspect, an embodiment of the present invention further provides a detection device, where the detection device includes:
one or more processors;
storage means for storing one or more programs;
when executed by the one or more processors, the one or more programs cause the one or more processors to implement a bed motion accuracy detection method as described in any of the above.
In a fourth aspect, embodiments of the present invention further provide a storage medium containing computer-executable instructions, which when executed by a computer processor, are configured to perform the bed motion accuracy detection method according to any of the embodiments.
Compared with the prior art, the technical scheme of the bed body movement precision detection method provided by the embodiment of the invention can obtain accurate actual in-place data of the bed body according to the reference projection image in each group of first projection images and the variation of the positions of the markers in the reference projection images, the deviation of the actual in-place data of the bed body relative to the expected in-place data is a single movement error of the bed body on the current track, the movement precision of the bed body in corresponding movement on the current track can be obtained after all single movement errors of the bed body are determined, and the method is simple, rapid and accurate.
Drawings
In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed to be used in the description of the embodiments are briefly introduced below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.
FIG. 1 is a flowchart of a bed movement accuracy detection method according to an embodiment of the present invention;
FIG. 2 is a schematic structural diagram of a bed provided in the first embodiment of the present invention;
FIG. 3 is a flowchart of a bed movement accuracy detection method according to a second embodiment of the present invention;
FIG. 4 is a flowchart of a bed movement accuracy detection method provided by the third embodiment of the present invention;
fig. 5 is a block diagram of a bed movement precision detection apparatus provided in the fourth embodiment of the present invention;
fig. 6 is a block diagram of a bed motion accuracy detecting device according to a fourth embodiment of the present invention;
fig. 7 is a block diagram of a detection apparatus according to a fifth embodiment of the present invention.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention clearer, the technical solutions of the present invention will be clearly and completely described through embodiments with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Example one
Fig. 1 is a flowchart of a bed movement precision detection method according to an embodiment of the present invention. The technical scheme of the embodiment is suitable for the situation of automatically determining the motion precision of the accelerator bed body. The method can be executed by the bed body movement precision detection device provided by the embodiment of the invention, and the device can be realized in a software and/or hardware mode and is configured to be applied in a processor of detection equipment. The method specifically comprises the following steps:
s101, at least two groups of first projection images for recording the start-stop position of the bed body in the current track motion are obtained, the first projection images comprise markers arranged in a mold body, the mold body is arranged above the bed body, the bed body moves in a one-way mode, and the number of times of movement is larger than or equal to two.
The die body is a three-dimensional QA (Quality Assurance, QA for short) die body, a marker is arranged at the center of the die body, the shape of the marker is preferably but not limited to a sphere, a cross or a cube, and the material of the marker is preferably metal. In this embodiment, the marker is exemplified as a tungsten ball.
Wherein, referring to fig. 2, the current track may be an X-axis track, a Y-axis track, a Z-axis track, or a circumferential track. The bed body 1 orbits along a circumference, namely rotates around an ISO shaft (rotating shaft).
The unidirectional motion on the X-axis track, the Y-axis track and the Z-axis track refers to that the bed body does unidirectional motion on the X-axis track or the Y-axis track in one-time motion of the bed body and the shooting process of a group of first projection images. And the directions of the multiple unidirectional movements can be the same or different.
When the bed body does unidirectional motion in an X-axis track or a Y-axis track, the method for acquiring the first projection image of the die body can be selected as follows: the mold body is placed on the bed body and positioned near the isocenter of the accelerator, and an imaging flat plate of an Electronic Portal Imaging Device (EPID) is extended to a position below the bed plate by a certain distance. Taking the current position as a starting point, and controlling the EPID to shoot a first projection image; after the first projection image is shot, controlling the bed body to move for a first set distance along the X-axis track or the Y-axis track, pausing when the movement of the first set distance is finished, and controlling the EPID to shoot a first projection image again during the pausing; after the first projection image is shot, controlling the bed body to move along the X-axis track or the Y-axis track for a second set distance, pausing when the movement of the second set distance is finished, and controlling the EPID to shoot a first projection image again during pausing; and analogizing until the bed body is controlled to move for the Nth set distance along the X-axis track or the Y-axis track and pause, and controlling the EPID to shoot a first projection image. The first set distance, the second set distance, and other set distances may be the same or different.
When the bed body moves unidirectionally on the Z-axis track, the method for acquiring the first projection image of the mold body can be selected as follows: the mold body is placed on the bed body and located near the isocenter of the accelerator, and the imaging flat plate of the EPID is stretched to a certain distance from the side face of the bed plate, so that a first projection image shot by the EPID is a side view of the mold body. Taking the current position as a starting point, and controlling the EPID to shoot a first projection image; after the first projection image is shot, controlling the bed body to move along the Z-axis track for a first set distance, pausing when the movement of the first set distance is finished, and controlling the EPID to shoot a first projection image again during pausing; after the first projection image is shot, controlling the bed body to move along the Z-axis track for a second set distance, pausing when the movement of the second set distance is finished, and controlling the EPID to shoot a first projection image again during pausing; and repeating the steps until the bed body is controlled to move for the Nth set distance along the Z-axis track and pause, and controlling the EPID to shoot a first projection image again during the pause. The first set distance, the second set distance, and other set distances may be the same or different.
When the bed body does unidirectional motion on the circumferential track, the method for acquiring the first projection image of the mold body can be selected as follows: and placing the die body on the bed body, positioning the die body near the isocenter of the accelerator, and stretching the imaging flat plate of the EPID to a certain distance from the bottom of the bed plate. Controlling the EPID to shoot a first projection image by taking the-90 degrees as a starting point; after the first projection image is shot, controlling the bed body to rotate on the circumferential track by a first set angle, namely controlling the bed body to rotate by the first set angle around an ISO shaft (rotating shaft), pausing after the first set angle is rotated, and controlling the EPID to shoot a first projection image again during pausing; after the first projection image is shot, controlling the bed body to rotate around the ISO shaft by a second set angle, pausing after the second set angle is rotated, and controlling the EPID to shoot a first projection image again during pausing; and repeating the steps until the bed body is controlled to rotate around the ISO shaft by the Nth set angle and then pause, and controlling the EPID to shoot a first projection image during the pause. The first set angle, the second set angle, and other various set angles may be the same or different.
Of course, in some embodiments, the end point of the previous movement of the bed may not be the starting point of the subsequent movement. The bed body only needs to make one-way forward segmental motion on the current track, and at least two motions in the N motions are taken as statistical objects. It can be understood that when the bed is at the starting point and the ending point of the segment motion as the statistical object, the first projection image of the EPID phantom needs to be controlled separately.
It can be understood that the bed body does unidirectional motion along any track and needs to ensure that the position of the EPID is not moved and the die body is always positioned in the shooting range of the EPID.
It should be noted that the unidirectional motion on the circular orbit means that the bed body only moves clockwise or counterclockwise along the circular orbit in the process of one-time rotation of the bed body and shooting of a group of first projection images. The rotation directions of the multiple unidirectional motions can be the same or different.
And S102, regarding each group of first projection images, taking the first projection image corresponding to the starting point of the bed body movement as a reference projection image, and taking the first projection image corresponding to the ending point of the bed body movement as a comparison projection image.
In the embodiment, two first projection images corresponding to each unidirectional movement of the bed body are used as a group of first projection images, the first projection image shot when the bed body is positioned at the starting point before the unidirectional movement is used as a reference projection image, and the first projection image shot when the bed body reaches the end point is used as a comparison projection image.
It can be understood that if the unidirectional motion mode of the bed body is unidirectional sectional continuous motion, the first projection image with the number N corresponds to the end point of the previous unidirectional motion of the bed body and the starting point of the next unidirectional motion of the bed body. For this reason, the present embodiment uses this first projection image as both a comparative projection image in a set of first projection images corresponding to the previous one-way motion and a reference projection image in a set of first projection images corresponding to the subsequent one-way motion.
S103, determining and comparing the variation of the position of the marker in the projection image relative to the position of the marker in the reference projection image and the deviation of the actual in-place data corresponding to the variation relative to the corresponding expected in-place data, and taking the deviation as a single movement error of the corresponding movement of the bed body on the current track.
When the bed body moves unidirectionally along an X-axis track, a Y-axis track or a Z-axis track, the actual in-place data and the expected in-place data are respectively an actual movement distance and an expected movement distance; when the bed body does unidirectional motion along the circumferential track, the actual in-place data and the expected in-place data are the actual rotating angle and the expected rotating angle respectively. And the expected movement distance and the expected rotation angle can be read from the corresponding encoders of the bed body.
When the bed body does unidirectional motion on an X-axis track or a Y-axis track, the method for determining the single motion error comprises the following steps: for each set of first projection images, calculating an image distance between the marker in the comparison projection image and the reference projection image; calculating the corresponding magnification ratio of the reference projection image; taking the ratio of the image distance to the magnification ratio as the actual movement distance of the bed body; and taking the difference value of the actual movement distance of the bed body and the expected movement distance as the single movement error of the bed body on the X-axis track or the Y-axis track.
Taking the bed body to do unidirectional sectional continuous motion along the X axis as an example, the center coordinates of the tungsten ball in the first group of first projection images are respectively (I)0x，I0y) and (I)1x，I1y) of the first projection image, the center coordinates of the tungsten sphere in the second projection image are respectively (I)1x，I1y) and (I)2x，I2y), and so on, the tungsten sphere center coordinates in the I-th group of first projection images are respectively (I)i-1x，Ii-1y) and (I)ix，Iiy). The fitting radiuses of the tungsten spheres of the first group of first projection images are respectively R0And R1The image distance between the centers of two tungsten spheres is
Figure BDA0002583931590000081
And the magnification ratio of the reference projection image in the set of first projection images is
Figure BDA0002583931590000082
The actual distance between the centers of the two tungsten spheres is
Figure BDA0002583931590000083
Where A is the pixel size. The desired movement distance of the bed is the movement distance of the bed recorded by the X-axis encoder. Let the expected movement distance be Lxe, the single movement error of the bed on the X-axis track corresponding to the first set of projection images is | Lx0Lxe | and so on, the single motion error | Lx of the bed on the X-axis track corresponding to the first projection image of the i-th group can be obtainedi-Lxe |, wherein LxiIs the actual distance between the centers of the two tungsten spheres in the ith set of first projection images.
When the bed body does unidirectional motion on the Z-axis orbit, the method for determining the single motion error comprises the following steps: for each group of first projection images, respectively determining the projection lengths of the preset length indexes of the markers in the reference projection image and the comparison projection image; respectively calculating the bed height corresponding to the reference projection image and the comparison projection image, and determining the bed height according to the SID of the EPID, the actual length of the preset length index of the marker and the projection length of the preset length index of the marker based on the similar triangle principle; taking the difference value of the bed height corresponding to the comparative projection image and the bed height corresponding to the reference projection image as the actual movement distance of the bed; and taking the difference between the actual movement distance and the expected movement distance as the single movement error of the bed body on the Z-axis track.
The preset length index is a length parameter of the marker, for example, when the marker is in the shape of a sphere, the preset length index can select the radius of the sphere; when the marker is in the shape of a cube, the preset length index may select the side length of the cube. The predetermined length index of the present embodiment is preferably the radius of the tungsten sphere.
Illustratively, the bed body makes unidirectional segmental continuous motion along a Z-axis track. Setting the fitting radius of the tungsten ball in the first projection image of the first group as R0And R1Then, according to the similar triangle theorem, one can obtain:
Figure BDA0002583931590000091
wherein R' is the actual radius of the tungsten ball; l is0The bed height corresponding to the reference projection image in the set of first projection images, L1The height of the bed body corresponding to the comparative projection image in the group of first projection images; SID (SID) is the Distance from the ray output device of the accelerator to the EPID plane. The SIDs in this embodiment are preferably all 145 cm. Therefore, the actual movement distance of the bed body corresponding to the group of first projection images on the Z-axis track is as follows:
Figure BDA0002583931590000092
the expected distance of movement recorded by the Z-axis orbital encoder is Lze, so the bed is on the Z-axis orbitThe first single motion error on a track can be expressed as: l Lz1-Lze |. By analogy, the single motion error | Lz of the bed body on the Z-axis track corresponding to the i-th group of the first projection images can be obtainedi-Lze |, wherein, LziAnd the actual movement distance of the bed body corresponding to the ith group of first projection images on the Z-axis track is obtained.
When the bed body does unidirectional motion on the circular orbit, namely the bed body rotates around an ISO shaft (rotating shaft) in a unidirectional subsection and continuous mode, the method for determining the single motion error of the bed body comprises the following steps: fitting the central points of the markers in all the first projection images to obtain the rotation center of the bed body; for each group of first projection images, taking a vector of the rotation center in the reference projection image pointing to the center point of the marker as a first vector, taking a vector of the rotation center in the comparative projection image pointing to the center point of the marker as a second vector, and taking an included angle between the first vector and the second vector as an actual rotation angle of the bed body; and taking the difference value between the actual rotating angle of the bed body rotating each time and the corresponding expected rotating angle as the single movement error of the bed body on the rotating track.
Illustratively, the bed body makes unidirectional rotation motion around an ISO shaft. The bed body rotates anticlockwise from-90 degrees to 90 degrees, the bed body pauses moving at intervals of 10 degrees, a first projection image is shot at the position with SID being 145cm through EPID, 19 first projection images containing the tungsten ball are obtained in total, and the coordinates of the center of the tungsten ball are respectively A0, A1, A2, A3 and A4 … … A18. According to the distribution track of the tungsten ball in the 19 first projection images, the rotation center of the tungsten ball, namely the rotation center Ac of the bed body, namely the ISO axis is determined. The-90 degree position is taken as the initial position of the bed body. For the first set of first projection images, the center of the tungsten ball in the comparison projection image is rotated by theta compared with the center of the tungsten ball in the reference projection image0Degree of, wherein θ0Can be expressed as:
Figure BDA0002583931590000101
if the corresponding desired angle of rotation is α, the single motion error of the bed in the circumferential orbit can be expressed as | θ |0α | by analogy, the bed corresponding to the first projection image of the ith group can be obtainedError of single movement | theta of body on circular orbiti- α |, where θiIs the rotation angle of the center of the tungsten sphere in the comparison projection image in the i-th group of first projection images compared with the center of the tungsten sphere in the reference projection image.
And S104, determining the motion precision of the bed body in corresponding motion on the current track according to all single motion errors of the bed body.
And after all single motion errors of the bed body on the current track are obtained, taking the maximum value of all the single motion errors as the one-way motion precision of the bed body on the current track.
For example, the precision of the one-way motion of the bed body on the X-axis track can be expressed as: p ═ max (| Lx)0-Lxe|，|Lx1-Lxe|…|Lxi-Lxe |); the one-way motion precision of the bed body on the Y-axis track can be expressed as follows: max (| Ly)0-Lye|，|Ly1-Lye|…|Lyi-Lye |); the one-way motion precision of the bed body on the Z-axis track can be expressed as follows: max (| Lz)1-Lze|，|Lz2-Lze|…|Lzi-Lze |); the one-way motion precision of the bed body rotating around the ISO axis can be expressed as follows: p ═ max (| θ)0-α|，|θ1-α|，…|θi-α|)。
Compared with the prior art, the technical scheme of the bed body movement precision detection method provided by the embodiment of the invention can obtain accurate actual in-place data of the bed body according to the variation of the positions of the markers in the reference projection image and the reference projection image in each group of first projection images, the difference value of the actual in-place data and the expected in-place data of the bed body is a single movement error of the bed body on the current track, the movement precision of the bed body in one-way movement on the current track can be obtained after all the single movement errors of the bed body are determined, and the method is simple, rapid and accurate.
Example two
Fig. 3 is a flowchart of a bed movement precision detection method provided in the second embodiment of the present invention. Before the embodiment of the present invention is implemented, the steps of the SID calibration method by the EPID are added.
Correspondingly, the method of the embodiment comprises the following steps:
s201, acquiring second projection images of the phantom at different positions of the bed body through the EPID.
And placing a mold body on the surface of the bed body, wherein a tungsten ball is arranged in the mold body, the radius of the tungsten ball is R', and controlling the bed body to move until the tungsten ball is moved to the position near the isocenter of the accelerator. Extending the flat plate of the EPID to a certain distance below the bed body, leveling the flat plate by a level ruler, and controlling the EPID to shoot a second projection drawing I1 of the die body; keeping the flat plate still, dragging the tungsten ball to move a certain distance L1 through a high-precision displacement table, and then shooting a second projection I2 of the die body.
The displacement table is an existing device, and this embodiment is not specifically limited thereto.
S202, determining a first magnification ratio according to the actual distance between the two different positions and the image distance of the marker in the two second projection images, and determining a second magnification ratio according to the actual length of the preset length index of the marker and the projection length of the preset length index of the marker in any one second projection image.
After the two second projection images are obtained, dark field correction and gain correction are carried out on the two second projection images, then the approximate positions of the tungsten spheres in the two second projection images are determined based on the image gray distribution, then boundary extraction and binarization processing are carried out on the two second projection images respectively to update the two second projection images, circle fitting is carried out on the projections of the tungsten spheres in the two updated second projection images to obtain the outlines of the tungsten spheres in the two second projection images respectively, and the coordinates and the radius of the circle center of the tungsten sphere are determined according to the outline of the tungsten sphere, wherein the circle center is (I) respectively1x，I1y) and (I)2x，I2y) with radii R1 and R2, respectively.
By representing the actual distance between the two different locations as L1, the first magnification of the EPID may be represented as:
Figure BDA0002583931590000121
where A is the pixel size. The second magnification of the EPID may be expressed as:
Figure BDA0002583931590000122
wherein R' is the radius of the tungsten sphere, and the radius of the tungsten sphere in this embodiment is preferably 2 cm.
And S203, taking the ratio of the first amplification ratio to the second amplification ratio as a correction factor of the amplification ratio.
Because the X-ray source is not an ideal point source, the X-ray penetration capability is strong, and a penumbra exists when an object is imaged, so that M1 and M2 are not completely equal, and the expressions of M1 and M2 can obtain that when the radiation source of the EPID is positioned above the bed, the correction factor k between the magnification ratio and the actual magnification ratio of all the shot projection images is:
Figure BDA0002583931590000123
it will be appreciated that the correction factor may modify the magnification of the first projection image in the previous embodiment to update the magnification of the first projection image.
S204, calibrating the SID of the EPID according to the correction factor and the projection length of the preset length index of the marker in any second projection image.
It will be appreciated that when the tungsten sphere radius R', the projection radius R0 of the tungsten sphere in the second projection image, and the correction factor k are known, they can be obtained according to the triangle-like principle:
Figure BDA0002583931590000131
where a is the pixel size. In this embodiment R' is preferably 2cm and SID 145 cm.
S205, at least two groups of first projection images for recording the start-stop position of the bed body in the current track motion are obtained, the first projection images comprise markers arranged in a mold body, the mold body is arranged above the bed body, the bed body moves in a one-way motion mode or a back-and-forth motion mode, and the number of times of movement is larger than or equal to two.
And S206, regarding each group of first projection images, taking the first projection image corresponding to the starting point of the bed body movement as a reference projection image, and taking the first projection image corresponding to the ending point of the bed body movement as a comparison projection image.
S207, determining and comparing the variation of the position of the marker in the projection image relative to the position of the marker in the reference projection image, and the deviation of actual in-place data corresponding to the variation relative to corresponding expected in-place data, and taking the deviation as a single movement error of the corresponding movement of the bed body on the current track.
And S208, determining the motion precision of the bed body in corresponding motion on the current track according to all single motion errors of the bed body.
According to the embodiment of the invention, before the first projection image is acquired, the SID of the EPID is calibrated, so that the quality of the first projection image is improved, and the correction factor of the magnification ratio of the first projection image corresponding to the X-axis track or the Y-axis track is determined, so that the accuracy of the magnification ratio of the first projection image is improved, and the accuracy of the determined movement precision of the bed body in the X-axis track or the Y-axis track is improved.
EXAMPLE III
Fig. 4 is a flowchart of a bed movement precision detection method provided by the third embodiment of the invention. On the basis of any embodiment, the embodiment of the invention is additionally provided with a method for detecting the reciprocating motion precision of the bed body.
Correspondingly, the method of the embodiment comprises the following steps:
s301, at least two groups of first projection images for recording the starting and stopping positions of the bed body in the current track motion are obtained, the first projection images comprise markers arranged in a mold body, the mold body is arranged above the bed body, the bed body moves in a reciprocating mode, and the moving times are more than or equal to two times.
When the bed body does reciprocating motion on the X-axis track or the Y-axis track, the method for acquiring the first projection image of the die body can be selected as follows: and placing the die body on the bed body, positioning the die body near the isocenter of the accelerator, and stretching the imaging flat plate of the EPID to a position below the bed plate by a certain distance. Taking the current position as a starting point, and controlling the EPID to shoot a first projection image; after the first projection image is shot, controlling the bed body to do reciprocating motion with a first set distance along the X-axis track or the Y-axis track, pausing when the reciprocating motion with the first set distance is finished, and controlling the EPID to shoot a first projection image again during the pausing; after the first projection image is shot, controlling the bed body to do reciprocating motion with the distance being a second set distance along the X-axis track or the Y-axis track, pausing when the reciprocating motion with the second set distance is finished, and controlling the EPID to shoot a first projection image again during pausing; and repeating the steps until the bed body is controlled to finish the Nth reciprocating motion on the X-axis track or the Y-axis track. The first set distance, the second set distance, and other set distances may be the same or different.
When the bed body does reciprocating motion on the Z-axis track, the method for acquiring the first projection image of the die body can be selected as follows: the mold body is placed on the bed body and located near the isocenter of the accelerator, and the imaging flat plate of the EPID is stretched to a certain distance from the side face of the bed plate, so that a first projection image shot by the EPID is a side view of the mold body. Taking the current position as a starting point, and controlling the EPID to shoot a first projection image; after the first projection image is shot, controlling the bed body to do reciprocating motion with a first set distance along the Z axis, pausing when the reciprocating motion is finished, and controlling the EPID to shoot a first projection image again during pausing; after the first projection image is shot, controlling the bed body to do reciprocating motion with a distance of a second set distance along the Z-axis track, pausing when the reciprocating motion is finished, and controlling the EPID to shoot a first projection image again during pausing; and repeating the steps until the bed body is controlled to finish N times of reciprocating motion on the Z-axis track and corresponding first projection images are shot. The first set distance, the second set distance, and other set distances may be the same or different.
When the bed body does reciprocating motion on the circumferential track, the method for acquiring the first projection image of the mold body can be selected as follows: and placing the die body on the bed body, positioning the die body near the isocenter of the accelerator, and stretching the imaging flat plate of the EPID to a certain distance from the bottom of the bed plate. Taking the current position as a starting point, and controlling the EPID to shoot a first projection image; after the first projection image is shot, controlling the bed body to do reciprocating rotation movement with a rotation angle of a first set angle on the circumferential track, namely controlling the bed body to do reciprocating rotation movement with a rotation angle of the first set angle around an ISO shaft (a rotation shaft), pausing after the reciprocating rotation movement is finished, and controlling an EPID to shoot a first projection image again during pausing; after the shooting of the first projection image is finished, controlling the bed body to do reciprocating rotation movement with the rotation angle being a second set angle on the circumferential track, and after the reciprocating rotation movement is finished, controlling the EPID to shoot a first projection image again during the pause period; and repeating the steps until the bed body is controlled to finish N times of reciprocating rotation motions on the circumferential axis track and corresponding first projection images are shot. The first set angle, the second set angle, and other various set angles may be the same or different.
In some embodiments, for any orbit, the bed body is controlled to make a reciprocating motion by taking different positions as starting points, and a first projection image before the bed body leaves the starting points and a second projection image when the bed body finishes the reciprocating motion and returns to the starting points are shot.
It can be understood that the bed body does unidirectional motion along any track and needs to ensure that the position of the EPID is not moved and the die body is always positioned in the shooting range of the EPID.
And S302, regarding each group of first projection images, taking the first projection image corresponding to the starting point of the bed body movement as a reference projection image, and taking the first projection image corresponding to the ending point of the bed body movement as a comparison projection image.
In the embodiment, two first projection images corresponding to each reciprocating motion of the bed body are used as a group of first projection images, the first projection image shot when the bed body is located at a starting point before the reciprocating motion is used as a reference projection image, and the first projection image shot when the bed body finishes the reciprocating motion and returns to the starting point again is used as a comparison projection image.
It can be understood that if the bed repeatedly makes a back-and-forth movement with the same position as a starting point, the first projection image with the number N corresponds to both the ending point of the previous back-and-forth movement of the bed and the starting point of the subsequent back-and-forth movement of the bed. For this reason, the present embodiment uses the first projection image as both the comparative projection image in the set of first projection images corresponding to the previous reciprocation and the reference projection image in the set of first projection images corresponding to the subsequent reciprocation.
S303, determining and comparing the variation of the position of the marker in the projection image relative to the position of the marker in the reference projection image and the deviation of the actual in-place data corresponding to the variation relative to the corresponding expected in-place data, and taking the deviation as a single movement error of the bed body in reciprocating motion on the current track.
When the bed body does reciprocating motion along an X-axis track, a Y-axis track or a Z-axis track, the actual in-place data is the actual motion distance; when the bed body does unidirectional motion along the circumferential track, the actual in-place data is the actual rotation angle. In an ideal situation, when the bed body does the back-and-forth movement along the X-axis track, the Y-axis track, the Z-axis track or the circumferential track, the end point position of the bed body should coincide with the start point position, that is, in an ideal situation, the center of the tungsten ball in the comparative projection image should coincide with the center of the tungsten ball in the reference projection image, so that the expected in-place data of the embodiment is zero for the back-and-forth movement of the bed body.
When the bed body does reciprocating motion on an X-axis track or a Y-axis track, the method for determining the single motion error comprises the following steps: for each set of first projection images, calculating an image distance between the marker in the comparison projection image and the reference projection image; calculating the corresponding magnification ratio of the reference projection image; and taking the product of the image distance and the amplification ratio as the single motion error of the bed body on the X-axis track or the Y-axis track.
Take the bed body to do the reciprocating motion of the same starting point along the X axis as an example. The center coordinates of the tungsten ball in the first group of first projection images are respectively (I)0x，I0y) and (I)1x，I1y) of the first projection image, the center coordinates of the tungsten sphere in the second projection image are respectively (I)1x，I1y) and (I)2x，I2y), and so on, the tungsten sphere center coordinates in the I-th group of first projection images are respectively (I)i-1x，Ii- 1y) and (I)ix，Iiy). The fitting radiuses of the tungsten spheres of the first group of first projection images are respectively R0And R1The image distance between the centers of two tungsten spheres is
Figure BDA0002583931590000171
Where A is the pixel size. Since the magnification ratio of the reference projection image in the set of first projection images is
Figure BDA0002583931590000172
The correction factor of the amplification scale is k, and the expected in-place data is zero, so the actual distance between the centers of the two tungsten spheres, i.e. the first single motion error of the bed body on the X-axis track, can be expressed as:
Figure BDA0002583931590000173
where A is the pixel size. By analogy, the single motion error Lx of the bed body on the X-axis track corresponding to the i-th group of first projection images can be obtainedi。
When the bed body does unidirectional motion on the Z-axis orbit, the method for determining the single motion error comprises the following steps: for each group of first projection images, respectively determining the projection lengths of the preset length indexes of the markers in the reference projection image and the comparison projection image; respectively calculating the bed height corresponding to the reference projection image and the comparison projection image, wherein the bed height is determined based on a similar triangle principle when the SID of the EPID, the actual length of the preset length index of the marker and the projection length of the preset length index of the marker are known; and when the expected in-place data is zero, taking the difference value of the bed height corresponding to the comparative projection image and the bed height corresponding to the reference projection image as the single motion error of the bed on the Z-axis orbit.
Exemplarily, the bed body makes a reciprocating motion along the Z axis with the same starting point, and the fitting radii of the tungsten spheres in the first group of first projection images are respectively R0And R1Then, according to the similar triangle theorem, one can obtain:
Figure BDA0002583931590000181
wherein R' is the actual radius of the tungsten ball; l is0The bed height corresponding to the reference projection image in the set of first projection images, L1The height of the bed body corresponding to the comparative projection image in the group of first projection images; SID is preferably 145 cm. Therefore, the first single motion error of the bed body on the Z-axis track corresponding to the set of first projection images can be expressed as:
Figure BDA0002583931590000182
by analogy, the single motion error Lz of the bed body on the Z-axis track corresponding to the first projection image of the ith group can be obtainedi。
When the bed body does reciprocating motion on the circular orbit, namely when the bed body does reciprocating rotary motion around the rotating shaft, the method for determining the single motion error of the bed body comprises the following steps: fitting the central points of the markers in all the first projection images to obtain the rotation center of the bed body; and regarding each group of first projection images, taking a vector of the rotation center in the reference projection image pointing to the center point of the marker as a first vector, taking a vector of the rotation center in the comparative projection image pointing to the center point of the marker as a second vector, and taking an included angle between the first vector and the second vector as a single motion error of the bed body.
Illustratively, the bed makes a back-and-forth rotation movement at the same starting point on the circular orbit, for example, the bed rotates clockwise from zero degrees to different angles and then returns to zero degrees. And determining the rotation center of the tungsten ball, namely the rotation center Ac of the bed body, namely the ISO axis according to the distribution track of the tungsten ball in all the first projection images. The tungsten sphere center of the reference projection image in the first set of first projection images is set to a0, and the tungsten sphere center of the comparison projection image is set to a 1. Since the expected in-place data is zero, the rotation angle of the center of the tungsten sphere in the projected image compared with the center of the tungsten sphere in the reference projected image is the single motion error of the bed. The first single motion error can be expressed as:
Figure BDA0002583931590000191
by analogy, the first projection drawing of the ith group can be obtainedLike the single motion error theta of the corresponding bed body on the circular orbiti。
S304, determining the movement precision of the bed body in the reciprocating motion on the current track according to all single movement errors of the bed body.
And after all single motion errors of the bed body on the current track are obtained, taking the maximum value of all the single motion errors as the reciprocating motion precision of the bed body on the current track.
For example, the precision of the back-and-forth movement of the bed body on the X-axis track can be expressed as: max (Lx)0，Lx1，...Lxi) Wherein, LxiThe single motion error of the bed body corresponding to the ith group of first projection images on the X-axis track is represented, wherein i is 0 or any natural number; the reciprocating motion precision of the bed body on the Y-axis track can be expressed as follows: p ═ max (Ly)0，Ly1，…Lyi) Wherein, LyiThe single motion error of the bed body corresponding to the ith group of first projection images on the X-axis track is represented, wherein i is 0 or any natural number; the one-way motion precision of the bed body on the Z-axis track can be expressed as follows: p ═ max (Lz)0，Lz1，…Lzi) Wherein, LziThe single motion error of the bed body corresponding to the ith group of first projection images on the X-axis track is shown, wherein i is a natural number; the reciprocating motion precision of the bed body on the circular orbit can be expressed as follows: p ═ max (θ)0，θ1，…θi) Wherein, thetaiThe motion error of the bed body corresponding to the first projection image of the ith group on the circumferential track is single, and i is 0 or any natural number.
Compared with the prior art, according to the technical scheme of the bed body movement precision detection method provided by the embodiment of the invention, single movement errors of the bed body can be obtained according to the reference projection image in each group of first projection images and the variation of the positions of the markers in the reference projection images, the movement precision of the bed body in the reciprocating motion on the current track can be obtained after all the single movement errors of the bed body are determined, and the method is simple, rapid and accurate.
Example four
Fig. 5 is a block diagram of a bed movement precision detection apparatus provided in the embodiment of the present invention. The device is used for executing the technical scheme of the bed body motion precision detection method provided by any embodiment, and can be realized by software or hardware. The device includes:
the acquisition module 11 is used for acquiring at least two groups of first projection images for recording the start-stop position of the bed body in the current orbital motion, the first projection images comprise markers arranged in a mold body, the mold body is arranged above the bed body, the bed body moves in a one-way motion mode or a reciprocating motion mode, and the number of times of movement is more than or equal to two;
the image grouping module 12 is configured to, for each group of the first projection images, use the first projection image corresponding to the start point of the bed body movement as a reference projection image, and use the first projection image corresponding to the end point of the bed body movement as a comparison projection image;
a motion error determining module 13, configured to determine a variation of the position of the marker in the comparative projection image with respect to the position of the marker in the reference projection image, and a deviation of actual in-place data corresponding to the variation with respect to corresponding expected in-place data, and use the deviation as a single motion error of the bed moving on the current trajectory;
and the motion precision determining module 14 is used for determining the motion precision of the bed body in corresponding motion on the current track according to all the single motion errors of the bed body.
Optionally, the current track is an X-axis track or a Y-axis track, the bed body moves in a unidirectional manner, the actual in-place data is an actual moving distance, and the expected in-place data is an expected moving distance; correspondingly, the motion error determination module is used for calculating and comparing the image distance between the marker in the projection image and the reference projection image for each group of first projection images; calculating the corresponding magnification ratio of the reference projection image; taking the ratio of the image distance to the magnification ratio as the actual movement distance of the bed body; and taking the difference value of the actual movement distance of the bed body and the expected movement distance as the single movement error of the bed body on the corresponding track.
Optionally, the current orbit is an X-axis orbit or a Y-axis orbit, the bed body moves back and forth, a starting point of the back and forth movement coincides with an end point, the expected in-place data is zero, and correspondingly, the movement error determination module is configured to calculate and compare an image distance between the projection image and the marker in the reference projection image for each group of the first projection images; calculating the corresponding magnification ratio of the reference projection image; and taking the ratio of the image distance to the magnification ratio as the single motion error of the bed body on the X-axis track or the Y-axis track.
Optionally, the current motion track is a Z-axis track, the bed body motion mode is a one-way motion, the actual in-place data is an actual motion distance, and the expected in-place data is an expected motion distance; correspondingly, the motion error determining module is used for respectively determining the projection lengths of the preset length indexes of the markers in the reference projection image and the comparison projection image for each group of first projection images; based on the principle of similar triangles, respectively calculating the bed height corresponding to the reference projection image and the comparison projection image according to the SID of the EPID, the actual length of the preset length index of the marker and the projection length of the preset length index of the marker; taking the difference value of the bed height corresponding to the comparative projection image and the bed height corresponding to the reference projection image as the actual movement distance of the bed; and taking the difference between the actual movement distance and the expected movement distance as the single movement error of the bed body on the Z-axis track.
Optionally, the current orbit is a Z-axis orbit, the bed body moves back and forth, a starting point of the back and forth movement coincides with an end point, the expected in-place data is zero, and correspondingly, the movement error determination module is configured to, for each group of the first projection images, respectively determine projection lengths of the preset length indexes of the markers in the reference projection image and the comparison projection image; based on the principle of similar triangles, respectively calculating the bed height corresponding to the reference projection image and the comparison projection image according to the SID of the EPID, the actual length of the preset length index of the marker and the projection length of the preset length index of the marker; and taking the difference value of the bed height corresponding to the comparative projection image and the bed height corresponding to the reference projection image as the single movement error of the bed on the Z-axis track.
Optionally, the current motion track is a circular track, the bed body motion mode is unidirectional motion, the actual in-place data is an actual rotation angle, and the expected in-place data is an expected rotation angle; correspondingly, the motion error determination module is used for fitting the marker center points in all the first projection images to obtain the rotation center of the bed body; for each group of first projection images, taking a vector of the rotation center in the reference projection image pointing to the center point of the marker as a first vector, taking a vector of the rotation center in the comparative projection image pointing to the center point of the marker as a second vector, and taking an included angle between the first vector and the second vector as an actual rotation angle of the bed body; and taking the difference value between the actual rotating angle of the bed body rotating each time and the corresponding expected rotating angle as the single movement error of the bed body on the rotating track.
Optionally, the current orbit is a circular orbit, the bed body moves in a reciprocating manner, the starting point of the reciprocating movement coincides with the end point, the expected in-place data is zero, and correspondingly, the movement error determination module is used for fitting the marker center points in all the first projection images to obtain the rotation center of the bed body; and regarding each group of first projection images, taking a vector of the rotation center in the reference projection image pointing to the center point of the marker as a first vector, taking a vector of the rotation center in the comparative projection image pointing to the center point of the marker as a second vector, and taking an included angle between the first vector and the second vector as a single motion error of the bed body.
Further, as shown in fig. 6, the apparatus further includes a calibration module 10, which includes:
the acquisition unit is used for acquiring second projection images of the die body at different positions of the bed body through the EPID;
the magnification ratio determining unit is used for determining a first magnification ratio according to the actual distance between the two different positions and the image distance of the marker in the two second projection images, and determining a second magnification ratio according to the actual length of the preset length index of the marker and the projection length of the preset length index of the marker in any one second projection image;
the correction unit is used for taking the ratio of the first amplification scale to the second amplification scale as a correction factor of the amplification scale;
and the calibration unit is used for completing calibration of the SID of the EPID according to the correction factor and the projection length of the preset length index of the marker in any second projection image.
Compared with the prior art, the technical scheme of the bed body movement precision detection device provided by the embodiment of the invention can obtain accurate actual in-place data of the bed body according to the reference projection image in each group of first projection images and the variation of the positions of the markers in the reference projection images, the deviation of the actual in-place data of the bed body relative to the expected in-place data is a single movement error of the bed body on the current track, the movement precision of the bed body in corresponding movement on the current track can be obtained after all single movement errors of the bed body are determined, and the method is simple, rapid and accurate.
The bed body motion precision detection device provided by the embodiment of the invention can execute the bed body motion precision detection method provided by any embodiment of the invention, and has the corresponding functional modules and beneficial effects of the execution method.
EXAMPLE five
Fig. 7 is a schematic structural diagram of a detecting apparatus according to a fifth embodiment of the present invention, as shown in fig. 7, the detecting apparatus includes a processor 201, a memory 202, an input device 203, and an output device 204; the number of the processors 201 in the device may be one or more, and one processor 201 is taken as an example in fig. 7; the processor 201, the memory 202, the input device 203 and the output device 204 in the apparatus may be connected by a bus or other means, and fig. 7 illustrates the example of connection by a bus.
The memory 202 is a computer-readable storage medium, and can be used to store software programs, computer-executable programs, and modules, such as program instructions/modules (for example, the obtaining module 11, the image grouping module 12, the motion error determining module 13, and the motion precision determining module 14) corresponding to the bed motion precision detection method in the embodiment of the present invention. The processor 201 executes various functional applications and data processing of the device by running software programs, instructions and modules stored in the memory 202, that is, the above-mentioned bed motion accuracy detection method is realized.
The memory 202 may mainly include a storage program area and a storage data area, wherein the storage program area may store an operating system, an application program required for at least one function; the storage data area may store data created according to the use of the terminal, and the like. Further, the memory 202 may include high speed random access memory, and may also include non-volatile memory, such as at least one magnetic disk storage device, flash memory device, or other non-volatile solid state storage device. In some examples, the memory 202 may further include memory located remotely from the processor 201, which may be connected to the device over a network. Examples of such networks include, but are not limited to, the internet, intranets, local area networks, mobile communication networks, and combinations thereof.
The input device 203 may be used to receive input numeric or character information and generate key signal inputs related to user settings and function controls of the apparatus.
The output device 204 may include a display device such as a display screen, for example, of a user terminal.
EXAMPLE six
Embodiments of the present invention also provide a storage medium containing computer-executable instructions, which when executed by a computer processor, perform a method for bed motion accuracy detection, the method comprising:
acquiring at least two groups of first projection images for recording the start-stop position of the bed body in the current orbital motion, wherein the first projection images comprise markers arranged in a mold body, the mold body is arranged above the bed body, the bed body moves in a one-way motion mode or a reciprocating motion mode, and the number of times of movement is more than or equal to two;
for each group of first projection images, taking the first projection image corresponding to the starting point of the bed body movement as a reference projection image, and taking the first projection image corresponding to the ending point of the bed body movement as a comparison projection image;
determining the variation of the position of the marker in the comparative projection image relative to the position of the marker in the reference projection image and the deviation of actual in-place data corresponding to the variation relative to corresponding expected in-place data, and taking the deviation as a single movement error of the corresponding movement of the bed body on the current track;
and determining the motion precision of the bed body in corresponding motion on the current track according to all single motion errors of the bed body.
Of course, the storage medium provided in the embodiments of the present invention includes computer-executable instructions, and the computer-executable instructions are not limited to the above-mentioned operations of the method, and may also perform related operations in the bed motion accuracy detection method provided in any embodiments of the present invention.
From the above description of the embodiments, it is obvious for those skilled in the art that the present invention can be implemented by software and necessary general hardware, and certainly, can also be implemented by hardware, but the former is a better embodiment in many cases. Based on such understanding, the technical solution of the present invention or a part contributing to the prior art may be embodied in the form of a software product, where the computer software product may be stored in a computer-readable storage medium, such as a floppy disk, a Read-Only Memory (ROM), a Random Access Memory (RAM), a FLASH Memory (FLASH), a hard disk or an optical disk of a computer, and includes a plurality of instructions for enabling a computer device (which may be a personal computer, a server, or a network device, etc.) to execute the bed motion accuracy detection method according to each embodiment of the present invention.
It should be noted that, in the embodiment of the bed motion accuracy detection apparatus, the units and modules included in the embodiment are only divided according to functional logic, but are not limited to the above division, as long as the corresponding functions can be realized; in addition, specific names of the functional units are only for convenience of distinguishing from each other, and are not used for limiting the protection scope of the present invention.
It is to be noted that the foregoing is only illustrative of the preferred embodiments of the present invention and the technical principles employed. It will be understood by those skilled in the art that the present invention is not limited to the particular embodiments described herein, but is capable of various obvious changes, rearrangements and substitutions as will now become apparent to those skilled in the art without departing from the scope of the invention. Therefore, although the present invention has been described in greater detail by the above embodiments, the present invention is not limited to the above embodiments, and may include other equivalent embodiments without departing from the spirit of the present invention, and the scope of the present invention is determined by the scope of the appended claims.

Claims (10)

1. A bed body movement precision detection method is characterized by comprising the following steps:
acquiring at least two groups of first projection images for recording the start-stop position of the bed body in the current orbital motion, wherein the first projection images comprise markers arranged in a mold body, the mold body is arranged above the bed body, the bed body moves in a one-way motion mode or a reciprocating motion mode, and the number of times of movement is more than or equal to two;
for each group of first projection images, taking the first projection image corresponding to the starting point of the bed body movement as a reference projection image, and taking the first projection image corresponding to the ending point of the bed body movement as a comparison projection image;
determining the variation of the position of the marker in the comparative projection image relative to the position of the marker in the reference projection image and the deviation of actual in-place data corresponding to the variation relative to corresponding expected in-place data, and taking the deviation as a single movement error of the corresponding movement of the bed body on the current track;
and determining the motion precision of the bed body in corresponding motion on the current track according to all single motion errors of the bed body.
2. The method according to claim 1, wherein the current orbit is an X-axis orbit or a Y-axis orbit, the actual in-place data is an actual moving distance, the expected in-place data is an expected moving distance, and the bed moving mode is a one-way moving mode;
correspondingly, the method for determining the single movement error of the bed body on the X-axis track or the Y-axis track comprises the following steps:
for each set of first projection images, calculating an image distance between the marker in the comparison projection image and the reference projection image;
calculating the corresponding magnification ratio of the reference projection image;
taking the ratio of the image distance to the amplification ratio as the actual movement distance of the bed body;
and taking the difference value of the actual movement distance of the bed body and the expected movement distance as the single movement error of the bed body on the corresponding track.
3. The method according to claim 1, wherein the current trajectory is an X-axis trajectory or a Y-axis trajectory, the bed moving manner is a back-and-forth movement, a starting point of the back-and-forth movement coincides with an end point, and the expected in-place data is zero, and the method for determining the single movement error of the bed on the X-axis trajectory or the Y-axis trajectory comprises:
for each set of first projection images, calculating an image distance between the marker in the comparison projection image and the reference projection image;
calculating the corresponding magnification ratio of the reference projection image;
taking the ratio of the image distance to the amplification ratio as the single movement distance of the bed body on an X-axis track or a Y-axis track;
and when the expected bit data is zero, taking the single-movement distance as a single-movement error.
4. The method according to claim 1, wherein the current motion track is a Z-axis track, the bed motion mode is a one-way motion, the actual in-place data is an actual motion distance, and the expected in-place data is an expected motion distance;
correspondingly, the method for determining the single movement error of the bed body in the Z axis comprises the following steps:
for each group of first projection images, respectively determining the projection lengths of the preset length indexes of the markers in the reference projection image and the comparison projection image;
based on the principle of similar triangles, respectively calculating the bed heights corresponding to the reference projection image and the comparison projection image according to the SID of the EPID, the actual length of the preset length index of the marker and the projection length of the preset length index of the marker;
taking the difference value of the bed height corresponding to the comparative projection image and the bed height corresponding to the reference projection image as the actual movement distance of the bed;
and taking the difference value between the actual movement distance and the expected movement distance as the single movement error of the bed body on the Z-axis track.
5. The method according to claim 1, wherein the current orbit is a Z-axis orbit, the bed moving manner is a reciprocating movement, a starting point of the reciprocating movement coincides with an end point, the expected in-place data is zero, and the method for determining the single movement error of the bed on the Z-axis comprises:
for each group of first projection images, respectively determining the projection lengths of the preset length indexes of the markers in the reference projection image and the comparison projection image;
based on the principle of similar triangles, respectively calculating the bed heights corresponding to the reference projection image and the comparison projection image according to the SID of the EPID, the actual length of the preset length index of the marker and the projection length of the preset length index of the marker;
and taking the difference value of the bed height corresponding to the comparative projection image and the bed height corresponding to the reference projection image as the single movement error of the bed on the Z-axis orbit.
6. The method according to claim 1, wherein the current motion orbit is a circular orbit, the bed motion mode is a one-way motion, the actual in-place data is an actual rotation angle, and the expected in-place data is an expected rotation angle;
correspondingly, the method for determining the single motion error of the bed body on the circular orbit comprises the following steps:
fitting the central points of the markers in all the first projection images to obtain the rotation center of the bed body;
for each group of first projection images, taking a vector of the rotation center in the reference projection image pointing to the center point of the marker as a first vector, taking a vector of the rotation center in the comparison projection image pointing to the center point of the marker as a second vector, and taking an included angle between the first vector and the second vector as an actual rotation angle of the bed body;
and taking the difference value between the actual rotating angle of the bed body rotating each time and the corresponding expected rotating angle as the single movement error of the bed body on the rotating track.
7. The method according to claim 1, wherein the current orbit is a circular orbit, the bed moves in a reciprocating manner, the starting point of the reciprocating movement coincides with the end point, the expected in-place data is zero, and the method for determining the single movement error of the bed on the circular orbit comprises:
fitting the central points of the markers in all the first projection images to obtain the rotation center of the bed body;
and regarding each group of first projection images, taking a vector of the rotation center in the reference projection image pointing to the center point of the marker as a first vector, taking a vector of the rotation center in the comparison projection image pointing to the center point of the marker as a second vector, and taking an included angle between the first vector and the second vector as a single motion error of the bed body.
8. The method as claimed in any one of claims 1 to 7, wherein the first projection image is acquired by an EPID of the accelerator, and before the acquiring at least two sets of first projection images for recording the start-stop position of the bed in the current orbital motion, the method further comprises:
acquiring second projection images of the die body at two different positions of the bed body through the EPID;
determining a first magnification ratio according to the actual distance between the two different positions and the image distance of the marker in the two second projection images; determining a second magnification ratio according to the actual length of the preset length index of the marker and the projection length of the preset length index of the marker in any second projection image;
taking the ratio of the first amplification scale to the second amplification scale as a correction factor of the amplification scale;
and completing the calibration of the SID of the EPID according to the correction factor and the projection length of the preset length index of the marker in any second projection image.
9. A bed body motion accuracy detection device, characterized by includes:
the device comprises an acquisition module, a display module and a control module, wherein the acquisition module is used for acquiring at least two groups of first projection images for recording the start-stop position of the bed body in the current orbital motion, the first projection images comprise markers arranged in a mold body, the mold body is arranged above the bed body, the motion mode of the bed body is one-way motion or reciprocating motion, and the motion times are more than or equal to two times;
the image grouping module is used for taking the first projection image corresponding to the starting point of the bed body movement as a reference projection image and taking the first projection image corresponding to the ending point of the bed body movement as a comparison projection image for each group of first projection images;
the movement error determining module is used for determining the variation of the position of the marker in the comparative projection image relative to the position of the marker in the reference projection image and the deviation of actual in-place data corresponding to the variation relative to corresponding expected in-place data, and taking the deviation as a single movement error of the bed body in corresponding movement on the current track;
and the motion precision determining module is used for determining the motion precision of the bed body in corresponding motion on the current track according to all single motion errors of the bed body.
10. A storage medium containing computer executable instructions for performing a bed motion accuracy detection method as claimed in any one of claims 1-8 when executed by a computer processor.
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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113310673A (en) * 2021-04-02 2021-08-27 深圳市世宗自动化设备有限公司 Method and device for detecting repetition precision, computer equipment and storage medium thereof

Citations (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2006061196A (en) * 2004-08-24 2006-03-09 Institute Of Physical & Chemical Research 3D fundus image construction and display device
US20070127622A1 (en) * 2005-11-14 2007-06-07 Main William T Unified quality assurance for a radiation treatment delivery system
CN201271432Y (en) * 2008-09-18 2009-07-15 山东新华医疗器械股份有限公司 Accurate radiotherapy bed
JP2012170483A (en) * 2011-02-17 2012-09-10 Fujitsu Ltd State detection device and state detection method
CN102753097A (en) * 2009-11-25 2012-10-24 登塔尔图像科技公司 Method for x-ray marker localization in 3d space in the presence of motion
CN103153553A (en) * 2010-08-27 2013-06-12 Abb研究有限公司 Vision-guided alignment system and method
US8605857B1 (en) * 2010-12-23 2013-12-10 Math Resolutions, LLC Method and system to reconstruct treatment dose to a patient from integrated exit-transit images of radiation fields taken during treatment
CN103785112A (en) * 2012-10-26 2014-05-14 瓦里安医疗系统公司 Template matching method for image-based detection and tracking of irregular shaped targets
US8872911B1 (en) * 2010-01-05 2014-10-28 Cognex Corporation Line scan calibration method and apparatus
CN104794718A (en) * 2015-04-27 2015-07-22 广东省第二人民医院 Single-image CT (computed tomography) machine room camera calibration method
CN107132239A (en) * 2017-05-25 2017-09-05 上海联影医疗科技有限公司 The colimated light system and moving cell positional precision monitoring method of a kind of Medical Devices
CN109297680A (en) * 2018-08-14 2019-02-01 深圳奥比中光科技有限公司 The detection method and device of light shaft offset error amount
CN109381216A (en) * 2017-08-08 2019-02-26 通用电气公司 The motion control device and method, computer program of the mobile bed board of patient
DE102017009040A1 (en) * 2017-09-27 2019-03-28 Städtisches Klinikum Dessau Method for EPID-based verification, correction and minimization of the isocenter of a radiotherapy device
CN110237445A (en) * 2019-07-05 2019-09-17 北京理工大学 In vivo three-dimensional dose monitoring and verification method based on EPID
CN110477936A (en) * 2019-08-20 2019-11-22 新里程医用加速器(无锡)有限公司 Beam-defining clipper scaling method, device, equipment and the medium of radiation imaging system

Patent Citations (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2006061196A (en) * 2004-08-24 2006-03-09 Institute Of Physical & Chemical Research 3D fundus image construction and display device
US20070127622A1 (en) * 2005-11-14 2007-06-07 Main William T Unified quality assurance for a radiation treatment delivery system
CN201271432Y (en) * 2008-09-18 2009-07-15 山东新华医疗器械股份有限公司 Accurate radiotherapy bed
CN102753097A (en) * 2009-11-25 2012-10-24 登塔尔图像科技公司 Method for x-ray marker localization in 3d space in the presence of motion
US8872911B1 (en) * 2010-01-05 2014-10-28 Cognex Corporation Line scan calibration method and apparatus
CN103153553A (en) * 2010-08-27 2013-06-12 Abb研究有限公司 Vision-guided alignment system and method
US8605857B1 (en) * 2010-12-23 2013-12-10 Math Resolutions, LLC Method and system to reconstruct treatment dose to a patient from integrated exit-transit images of radiation fields taken during treatment
JP2012170483A (en) * 2011-02-17 2012-09-10 Fujitsu Ltd State detection device and state detection method
CN103785112A (en) * 2012-10-26 2014-05-14 瓦里安医疗系统公司 Template matching method for image-based detection and tracking of irregular shaped targets
CN104794718A (en) * 2015-04-27 2015-07-22 广东省第二人民医院 Single-image CT (computed tomography) machine room camera calibration method
CN107132239A (en) * 2017-05-25 2017-09-05 上海联影医疗科技有限公司 The colimated light system and moving cell positional precision monitoring method of a kind of Medical Devices
CN109381216A (en) * 2017-08-08 2019-02-26 通用电气公司 The motion control device and method, computer program of the mobile bed board of patient
DE102017009040A1 (en) * 2017-09-27 2019-03-28 Städtisches Klinikum Dessau Method for EPID-based verification, correction and minimization of the isocenter of a radiotherapy device
CN109297680A (en) * 2018-08-14 2019-02-01 深圳奥比中光科技有限公司 The detection method and device of light shaft offset error amount
CN110237445A (en) * 2019-07-05 2019-09-17 北京理工大学 In vivo three-dimensional dose monitoring and verification method based on EPID
CN110477936A (en) * 2019-08-20 2019-11-22 新里程医用加速器(无锡)有限公司 Beam-defining clipper scaling method, device, equipment and the medium of radiation imaging system

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
余晓锷等: "CT机中诊视床运动精度的检测方法和结果", 《北京生物医学工程》 *
韩媛媛等: "Synergy加速器治疗床自动摆位准确性的验证", 《中国医学物理学杂志》 *

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113310673A (en) * 2021-04-02 2021-08-27 深圳市世宗自动化设备有限公司 Method and device for detecting repetition precision, computer equipment and storage medium thereof

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