Method for ct system balance detection analysis based on probe data

Abstract

The application discloses a CT system dynamic balance detection analysis method based on detector data, and comprises the following steps: establishing a high-attenuation point-shaped phantom body of overhanging eccentric type; collecting projection track data of the high-attenuation point-shaped phantom body in a detector based on differential rotating speed; calculating and analyzing a spatial circular track through the projection track data; detecting the phase and size of a dynamic unbalance amount of the spatial circular track; detecting the phase and size of a static unbalance amount of a rotating center offset track of a rotating plane; and observing the difference between the dynamic unbalance amount and the static unbalance amount of the differential rotating speed. The method solves the problem that the detection data of an unbalance amount detected by a sensor installed at a stator end cannot truly reflect the unbalance amount of a system in the prior art.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of CT system dynamic balance detection, in particular to a CT system dynamic balance detection and analysis method based on detector data. BACKGROUND

[0002] CT system is a scanning device through rotation exposure and data acquisition. The core principle of the device is to collect data through the relative accurate geometry between the rotating system and the scanned object (human body), and then reconstruct the collected data to obtain an image. The rotation speed of the system determines the time resolution performance of the system. With the progress of the industry technology, the rotation speed of the CT system has gradually become a competitive indicator of various CT system manufacturers.

[0003] The rotation process of the CT system can cause the shaking of the tilting part of the gantry. This instability affects the scanning accuracy and image quality, and may also affect the noise, safety and service life of the system. In terms of rotation, the degree of influence of the system on the unbalance is proportional to the square of the system speed in the case of unbalance determination, that is, the acceleration of the rotation speed of the CT system directly leads to higher dynamic balance requirements for the CT rotating part. As can be seen, the acceleration of the rotation speed greatly reduces the tolerance of the system to the dynamic balance.

[0004] The static balance state is the state in which the rotation axis of the rotating body passes through the center of mass. The dynamic balance state is the state in which the rotation axis of the rotating body coincides with the center of inertia of the rotating body. Dynamic balance is a special state of static balance, and if the rotating body has reached the static balance state, the unbalance can be eliminated by further adjustment to achieve the dynamic balance state. Therefore, in daily work, it is necessary to detect and adjust the dynamic balance state of the system for the system with high rotation speed, to further ensure the safety and normal use of the system.

[0005] In the prior art, the rotor part of the CT system is in transmission connection with the movable part of the bearing, and then the fixed part of the bearing is in transmission connection with the stator part of the system. Due to the large volume and mass of the whole system, it is difficult to test the dynamic balance of the whole system in suspension. The usual solution in the industry is to install a sensor at the stator end to detect the unbalance. However, due to the complexity of the internal connection of the rotor, the structure and mechanical properties of the stator, the detection data of the sensor often cannot truly represent the unbalance of the system. Therefore, it has been a difficult problem in the industry to more accurately detect the unbalance of the CT system. SUMMARY

[0006] To this end, the application provides a CT system dynamic balance detection analysis method based on detector data, which is based on system inherent components and inherent data acquisition mode to solve the problem that the detection data of the imbalance amount detected by the sensor installed at the stator end cannot truly represent the imbalance amount of the system in the prior art.

[0007] In order to achieve the above-mentioned purpose, the application provides the following technical scheme.

[0008] A CT system dynamic balance detection analysis method based on detector data, comprising the following steps:

[0009] Establishing a high-attenuation point-like phantom with a suspended eccentricity;

[0010] Rotating and collecting the projection trajectory data of the high-attenuation point-like phantom in the detector based on differential rotation speed, and calculating and analyzing the spatial circular trajectory based on the projection trajectory data;

[0011] Detecting the phase and size of the even imbalance amount calculated and analyzed by the spatial circular trajectory;

[0012] Detecting the phase and size of the static imbalance amount calculated and analyzed by the rotation center offset trajectory of the rotation plane;

[0013] Observing the difference between the even imbalance amount and the static imbalance amount of the differential rotation speed.

[0014] On the basis of the above technical scheme, the application is further described as follows.

[0015] As a further scheme of the application, the establishment of the high-attenuation point-like phantom with a suspended eccentricity specifically comprises:

[0016] The high-attenuation point-like phantom with a suspended eccentricity is installed at a spatial position that is relatively static with respect to the stator coordinate system and can be detected by the detector.

[0017] As a further scheme of the application, the rotating and collecting of the projection trajectory data of the high-attenuation point-like phantom in the detector based on differential rotation speed, and the calculation and analysis of the spatial circular trajectory based on the projection trajectory data specifically comprises:

[0018] The projection trajectory data of the detector plane and the spatial circular trajectory are in a one-to-one correspondence, and the projection trajectory data of the high-attenuation point-like phantom is collected at each angle in the circumferential direction using a rotating collection mode;

[0019] The trajectory of the high-attenuation point-like phantom in the stationary coordinate system in the rotating coordinate system space forms a spatial circular trajectory on a spatial plane, and the spatial circular trajectory is calculated and analyzed based on the projection trajectory data of the detector plane.

[0020] As a further scheme of the present application, the projection track data of the high-attenuation point-like object model on the detector is collected based on the differential rotation speed, and the spatial circular track is obtained by analyzing the projection track data, and specifically further comprising:

[0021] The projection track data of the point on the spatial circular track on the detector plane is an ellipse or a straight line, and the straight line is an ellipse with a short axis of zero.

[0022] As a further scheme of the present application, the projection track data of the high-attenuation point-like object model on the detector is collected based on the differential rotation speed, and the spatial circular track is obtained by analyzing the projection track data, and specifically further comprising:

[0023] The projection track data of the detector plane and the spatial circular track of the high-attenuation point-like object model are obtained by the high-low rotation speed switching rotation collection mode.

[0024] As a further scheme of the present application, the phase and size of the static imbalance are calculated and analyzed by detecting the spatial circular track, and specifically comprising:

[0025] The spatial angle and spatial angle phase of the corresponding rotation plane of the detector and the corresponding static plane of the spatial circular track are characterized by the projection components of the normal vector of the spatial circular track on the YOZ and XOZ planes y and x ;

[0026] The detectable spatial angle phase is calculated by cos(α y ) / cos(α x ), and the phase of the even imbalance is identified by the spatial angle phase; the amplitude of the spatial angle is arccoscos 2 α x +cos 2 α y , and the size of the even imbalance is indicated and calibrated by the spatial angle.

[0027] As a further scheme of the present application, the projection angle of the spatial circular track and the normal vector on the YOZ plane is y , which corresponds to the angle between the YOZ plane projection vector and the Z axis, and the projection angle of the spatial circular track and the normal vector on the XOZ plane is x , which corresponds to the angle between the XOZ plane projection vector and the Z axis.

[0028] As a further scheme of the present application, the phase and size of the static imbalance are calculated and analyzed by detecting the rotation center offset track of the rotation plane, and specifically comprising:

[0029] The rotation center of the rotation plane corresponding to the detector generates a deviation vector under the action of the static unbalance amount, and the components of the deviation vector on the rotation plane (X-Y) coordinate system are defined as ΔX and ΔY, respectively;

[0030] Based on the calculated ΔX and ΔY, the phase of the deviation vector is further calculated as arctan (ΔY / ΔX), and the identification of the phase angle indicates the phase of the static unbalance amount in the rotation coordinate system; the size of the deviation vector is ΔX 2 +ΔY 2 , and the size of the deviation indicates and calibrates the size of the static unbalance amount of the rotation system.

[0031] As a further scheme of the application, ΔY is calculated by the change value ΔCoverage of the number of channel covers of the projection of the rotation center deviation trajectory of the rotation plane (X-Y) on the detector plane; and ΔX is calculated by the position deviation ΔCenter of the projection of the rotation center deviation trajectory of the rotation plane (X-Y) on the detector surface.

[0032] As a further scheme of the application, the difference between the even unbalance amount and the static unbalance amount of the observed differentiated rotational speed is specifically as follows:

[0033] The relatively slow rotational speed observes a smaller even unbalance amount and static unbalance amount effect; and the relatively fast rotational speed observes a larger even unbalance amount and static unbalance amount effect.

[0034] The influence of the differentiated even unbalance amount and the static unbalance amount is differentiated by the factors of the influence of the centrifugal force on the differentiated rotational speed, and the observation of the phase and size of the unbalance amount is performed accordingly.

[0035] For the even unbalance amount, low-speed rotation and high-speed rotation scanning are performed respectively, and projection trajectory data is acquired, the spatial angle size and phase of the normal vector of the plane where the spatial circular trajectory is located and the ideal rotation axis are identified, and finally the identification of the even unbalance amount and the adjustment of the centroid plane are completed.

[0036] For the static unbalance amount, low-speed rotation and high-speed rotation scanning are performed respectively, and projection trajectory 5 data is acquired, the center phase angle of the rotation center deviation trajectory of the fan beam coordinate system (X-Y) and the rotation plane is identified, and finally the identification of the static unbalance amount and the adjustment of the angular phase are completed.

[0037] The application has the following beneficial effects:

[0038] The method projects X-rays emitted by a focal light source to a detector plane, and can obtain projection track data of the detector matrix at each circumferential rotation angle, and then can obtain a spatial circular track of the established high-attenuation point-like phantom in a rotating coordinate system based on the projection track data, and effectively realize detection and analysis of the unbalance amount by using the spatial circular track, so as to ensure the authenticity and accuracy of the detection data. BRIEF DESCRIPTION OF DRAWINGS

[0039] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings needed to be used in the embodiments or the prior art description will be briefly introduced as follows. The structures, proportions, sizes, etc. shown in the present description are only used to cooperate with the content disclosed in the present description, so as to be understood and read by those skilled in the art. Any modification of the structure, change of the proportional relationship or adjustment of the size, which does not affect the effects and purposes that can be achieved by the present application, should still fall within the scope of the technical content disclosed by the present application.

[0040] Figure 1 A system rotating coordinate system and a rotor layout schematic diagram in a CT system dynamic balance detection and analysis method based on detector data provided by the embodiments of the present application.

[0041] Figure 2 A spatial position of a high-attenuation point-like phantom and a projection schematic diagram thereof in a CT system dynamic balance detection and analysis method based on detector data provided by the embodiments of the present application.

[0042] Figure 3 A rotating acquisition high-attenuation point-like phantom projection schematic diagram in a CT system dynamic balance detection and analysis method based on detector data provided by the embodiments of the present application.

[0043] Figure 4 A phantom projection track and a detector projection schematic diagram under a slow rotation speed in a CT system dynamic balance detection and analysis method based on detector data provided by the embodiments of the present application.

[0044] Figure 5 A phantom projection track and a detector projection schematic diagram under a fast rotation speed in a CT system dynamic balance detection and analysis method based on detector data provided by the embodiments of the present application.

[0045] Figure 6 A track difference under a fast and slow rotation speed and an observable difference on a detector schematic diagram in a CT system dynamic balance detection and analysis method based on detector data provided by the embodiments of the present application.

[0046] Figure 7 A detection method schematic diagram of an even unbalance amount in a CT system dynamic balance detection and analysis method based on detector data provided by the embodiments of the present application.

[0047] Figure 8 The schematic diagram of the calculation and characterization method of the static imbalance amount in the CT system dynamic balance detection and analysis method based on detector data provided by the embodiment of the present application.

[0048] Figure 9 The schematic diagram of the offset component vector ΔY and the change of the projection channel coverage number in the static imbalance amount detection method in the CT system dynamic balance detection and analysis method based on detector data provided by the embodiment of the present application.

[0049] Figure 10 The schematic diagram of the offset component vector ΔX and the change of the projection channel coverage number in the static imbalance amount detection method in the CT system dynamic balance detection and analysis method based on detector data provided by the embodiment of the present application.

[0050] Figure 11 The schematic diagram of the flow of the CT system dynamic balance detection and analysis method based on detector data provided by the embodiment of the present application.

[0051] In the drawings, the components represented by each reference numeral are listed as follows:

[0052] Focus light source 1; detector 2; high-attenuation point-like object model 3; spatial circular trajectory 4; projection trajectory 5. DETAILED DESCRIPTION

[0053] The embodiments of the present application will be described herein below with reference to specific embodiments. Those skilled in the art can easily understand other advantages and effects of the present application from the content disclosed in the present specification. Obviously, the described embodiments are part of the embodiments of the present application, but not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0054] The terms such as "upper", "lower", "left", "right", "middle" and the like cited in the present specification are only for the convenience of clear description, and are not used to limit the scope of implementation of the present application. The change or adjustment of the relative relationship without substantial change of the technical content is also regarded as the implementation scope of the present application.

[0055] As shown in Figures 1 to 11 The embodiment of the present application provides a CT system dynamic balance detection and analysis method based on detector data. First, the reference Figure 1 , Figure 1The CT system rotating coordinate system (X-Y-Z) and its rotor layout as the measured workpiece are schematically shown. The CT system rotor is a precise geometric data acquisition system inherent to the CT system around the rotating axis (through the normal vector of the rotation plane at the rotation center), which can project the X-rays emitted by the focal point light source 1 to the detector 2 plane while rotating, and can obtain the projection track 5 data of the detector 2 matrix at each circumferential rotation angle, and further can obtain the spatial circular track 4 of the established high-attenuation point-like phantom 3 in the rotating coordinate system based on the projection track 5 data analysis, and effectively realize the detection and analysis of the unbalance.

[0056] The CT system dynamic balance detection and analysis method based on the detector data specifically includes the following steps:

[0057] Step S001: Establishing a suspended eccentric high-attenuation point-like phantom 3;

[0058] Among them, please refer to Figure 2 a and b in the stator coordinate system, the high-attenuation point-like phantom 3 is installed in the spatial position which is relatively static with the stator coordinate system and can be detected by the detector 2.

[0059] Step S002: Rotating and collecting the projection track 5 data of the high-attenuation point-like phantom 3 in the detector 2 based on the differential rotating speed, and calculating and analyzing the spatial circular track 4 through the projection track 5 data;

[0060] Among them, please refer to Figure 3 a and b, the track of the high-attenuation point-like phantom 3 in the stator coordinate system in the rotating coordinate system space forms a spatial circular track 4 on a spatial plane, so that the spatial plane where the spatial circular track 4 is located is used as the reference plane of the stator coordinate system.

[0061] The projection track 5 data of the point on the spatial circular track 4 on the detector 2 plane is an elliptical shape or a straight line, and the straight line is an ellipse with a short axis of zero.

[0062] The projection track 5 data of the detector 2 plane and the spatial circular track 4 are in one-to-one correspondence, the projection track 5 data of the high-attenuation point-like phantom 3 is collected at each circumferential angle by using the rotating collection mode, and then the spatial circular track 4 is calculated and analyzed through the projection track 5 data of the detector 2 plane.

[0063] Please refer to Figures 4 to 6 , the projection track 5 data of the detector 2 plane and the spatial circular track 4 of the high-attenuation point-like phantom 3 are obtained by the rotating collection mode with high and low rotating speed switching. Among them, Figure 4 is the phantom projection track and the detector projection diagram under the slow rotating speed, Figure 5The trajectory of the phantom projection and the projection image of the detector at high speed, Figure 6 The difference of the trajectory at high and low speed and the observable difference image on the detector.

[0064] Step S003: Calculate and analyze the phase and size of the even imbalance by the detected spatial circular trajectory 4;

[0065] In which, please refer to Figure 7 a1-3, b1-3 and c1-3 in the formula, Figure 7 a-1 to d-1 in the formula are different spatial angles and spatial angle phases, the spatial angle and spatial angle phase between the rotation plane corresponding to the detector 2 and the stationary plane of the spatial circular trajectory 4 are projected on the YOZ and XOZ planes through the normal vector of the spatial circular trajectory 4, and the projection components are α y and α x for characterization, please continue to refer to Figure 7 a1-3, b1-3 and c1-3 in the formula, Figure 7 a-2 to d-2 in the formula are the projection angles of the spatial circular trajectory 4 and the normal vector on the YOZ plane, that is, α y corresponding to the angle between the YOZ plane projection vector and the Z axis, Figure 7 a-3 to d-3 in the formula are the projection angles of the spatial circular trajectory 4 and the normal vector on the XOZ plane, that is, α x corresponding to the angle between the XOZ plane projection vector and the Z axis.

[0066] Please refer to Figure 8 , calculate cos(α y ) / cos(α x ) to detect the spatial angle phase, and identify the phase of the even imbalance through the spatial angle phase; the amplitude of the spatial angle is arccoscos 2 α x +cos 2 α y , and the size of the even imbalance is indicated and calibrated through the spatial angle size.

[0067] Step S004: Calculate and analyze the phase and size of the static imbalance by the detected rotation center offset trajectory of the rotation plane;

[0068] In which, please refer to Figures 9 to 10 Since the rotation center offset of the rotation plane (X-Y) corresponding to the detector 2 is the effect of the static imbalance, the components of the offset vector on the rotation plane (X-Y) coordinate system are defined as ΔX and ΔY. Figure 9 The offset component vector ΔY of the static imbalance detection method and the change image of the number of projection channels covered by the detector 2 are calculated and determined by the change value ΔCoverage of the number of channel covers of the rotation center offset trajectory of the rotation plane (X-Y) projected on the detector 2 plane.Figure 10 For the static unbalance amount detection method, the offset vector ΔX and its projection channel coverage number change diagram are offset, and the position offset amount ΔCenter of the rotation center offset trajectory projected on the surface of the detector 2 is calculated to determine ΔX.

[0069] Based on the calculated ΔX and ΔY, the phase of the offset vector is further calculated as arctan(ΔY / ΔX), and the phase of the static unbalance amount in the rotating coordinate system is indicated by the identification of the phase angle; the offset vector size is ΔX 2 +ΔY 2 , and the offset vector size indicates and calibrates the size of the static unbalance amount of the rotating system.

[0070] Step S005: Observe the difference between the static unbalance amount and the static unbalance amount of the differentiated rotating speed;

[0071] Among them, please refer to Figure 11 , the smaller even unbalance amount and static unbalance amount effect is observed at the relatively slow rotating speed; the larger even unbalance amount and static unbalance amount effect is observed at the relatively fast rotating speed.

[0072] The influence of the differentiated even unbalance amount and the static unbalance amount is differentiated by the influence of the centrifugal force on the differentiated rotating speed, and the phase and size of the unbalance amount are observed.

[0073] For even unbalance amount, low speed rotation and high speed rotation scanning are respectively carried out, and projection trajectory 5 data is acquired, the spatial angle size and phase of the normal vector of the space circle trajectory and the ideal rotating shaft are identified, and finally the identification of even unbalance amount and the adjustment of its mass center plane are completed.

[0074] For static unbalance amount, low speed rotation and high speed rotation scanning are respectively carried out, and projection trajectory 5 data is acquired, the phase angle of the fan beam coordinate system (X-Y) and the rotating center (the center of the rotating center offset trajectory of the rotating plane) is identified, and finally the identification of static unbalance amount and the angle phase adjustment are completed.

[0075] The embodiment of the application also provides a machine readable storage medium, which stores instructions for causing a machine to execute the CT system dynamic balance detection analysis method based on detector data as described herein. Specifically, a system or device equipped with a storage medium can be provided, and the storage medium stores software program code for realizing the functions of any one of the above embodiments, and the computer (or CPU or MPU) of the system or device reads and executes the program code stored in the storage medium.

[0076] In this case, the program code read from the storage medium itself can realize the functions of any one of the above embodiments, so the program code and the storage medium storing the program code constitute a part of the application.

[0077] The storage medium for supplying the program code includes a floppy disk, a hard disk, a magneto-optical disk, an optical disk (such as CD-ROM, CD-R, CD-RW, DVD-ROM, DVD-RAM, DVD-RW, DVD+RW), a magnetic tape, a nonvolatile memory card, and a ROM. Alternatively, the program code is downloaded from a server computer via a communication network.

[0078] Further, it should be understood that not only the program code read by the computer is executed, but also part or all of the actual operation is performed by the operating system or the like operating on the computer based on the instructions of the program code, thereby realizing the function of any one of the above-described embodiments.

[0079] Further, it should be understood that the program code read by the storage medium is written into the memory provided in the expansion board inserted into the computer or the memory provided in the expansion unit connected to the computer, and then part or all of the actual operation is performed by the CPU or the like mounted on the expansion board or the expansion unit based on the instructions of the program code, thereby realizing the function of any one of the above-described embodiments.

[0080] Although the present application has been fully described in connection with the preferred embodiments thereof with reference to the accompanying drawings, it is to be noted that various changes or modifications are apparent to those skilled in the art and can be made without departing from the scope of the present application. Accordingly, the scope of the present application should be gauged by the claims and not by the description which has been presented above only by way of an example.

Claims

1. A method for dynamic balance detection and analysis of a CT system based on detector data, characterized in that, Includes the following steps: Establish a suspended eccentric high-attenuation point phantom (3); Based on the differential rotation speed, the projection trajectory (5) data of the high-attenuation point phantom (3) on the detector (2) is collected, and the spatial circular trajectory (4) is obtained by calculation and analysis through the projection trajectory (5) data. The phase and magnitude of the even imbalance quantity are calculated and analyzed by probing the spatial circular trajectory (4); The detection of the spatial circular trajectory (4) involves calculating and analyzing the phase and magnitude of the even imbalance, specifically including: The spatial angle and spatial angle phase between the rotating plane corresponding to the detector (2) and the stationary plane corresponding to the spatial circular trajectory (4) are projected onto the YOZ and XOZ planes through the normal vector of the spatial circular trajectory (4). y and α x To characterize; Calculate cos(α) y ) / cos(α) x It can detect the phase of a spatial angle, and identify the phase of the indicator couple imbalance through this spatial angle phase; the magnitude of the spatial angle is... The magnitude of the space angle indicates and calibrates the magnitude of the even unbalance. The projection angle of the spatial circular trajectory (4) and its normal vector onto the YOZ plane is α. y The angle between the projection vector onto the YOZ plane and the Z-axis is the projection angle of the spatial circular trajectory (4) and its normal vector onto the XOZ plane, which is α. x The angle between the projection vector onto the XOZ plane and the Z-axis; The phase and magnitude of static unbalance are calculated and analyzed by detecting the offset trajectory of the rotation center of the rotating plane. The difference between the even imbalance and static imbalance of the differential rotational speed was observed.

2. The method for dynamic balance detection and analysis of a CT system based on detector data according to claim 1, characterized in that, The establishment of the suspended eccentric high-attenuation point phantom (3) specifically includes: The suspended eccentric high-attenuation point-shaped phantom (3) is installed in a spatial position that is relatively stationary with respect to the stator coordinate system and can be detected by the detector (2).

3. The method for dynamic balance detection and analysis of a CT system based on detector data according to claim 2, characterized in that, The method of collecting the projection trajectory (5) data of the high-attenuation point phantom (3) on the detector (2) based on differential rotational speed, and calculating and analyzing the spatial circular trajectory (4) through the projection trajectory (5) data, specifically includes: The projection trajectory (5) data of the detector (2) plane is in one-to-one correspondence with the spatial circular trajectory (4). The projection trajectory (5) data of the high-attenuation point-shaped object phantom (3) is collected at various angles in the circumference using the rotation acquisition mode. The trajectory of the high-attenuation point-like object (3) in the stationary coordinate system forms a spatial circular trajectory (4) on a spatial plane in the rotating coordinate system. The spatial circular trajectory (4) is obtained by calculation and analysis using the projection trajectory (5) data of the detector (2) plane.

4. The method for dynamic balance detection and analysis of a CT system based on detector data according to claim 3, characterized in that, The method of collecting the projection trajectory (5) data of the high-attenuation point phantom (3) on the detector (2) based on differential rotational speed, and calculating and analyzing the spatial circular trajectory (4) through the projection trajectory (5) data, specifically also includes: The projection trajectory (5) of the point on the spatial circular trajectory (4) on the plane of the detector (2) is an elliptical shape or a straight line, which is an ellipse with a minor axis of zero.

5. The method for dynamic balance detection and analysis of a CT system based on detector data according to claim 4, characterized in that, The method of collecting the projection trajectory (5) data of the high-attenuation point phantom (3) on the detector (2) based on differential rotational speed, and calculating and analyzing the spatial circular trajectory (4) through the projection trajectory (5) data, specifically also includes: The projection trajectory (5) data of the detector (2) plane and the spatial circular trajectory (4) of the high-attenuation point-like object phantom (3) are obtained by switching between high and low speed rotation acquisition mode.

6. The method for dynamic balance detection and analysis of a CT system based on detector data according to claim 5, characterized in that, The calculation and analysis of the phase and magnitude of the static unbalance quantity based on the offset trajectory of the rotation center of the detection rotating plane specifically includes: The rotation center of the rotating plane corresponding to the detector (2) generates an offset vector under the action of static unbalance. The components of the offset vector in the rotating plane (XY) coordinate system are defined as ∆X and ∆Y respectively. Based on the calculated ∆X and ∆Y, the phase of the offset vector is further calculated as arctan(∆Y / ∆X). This phase is used to indicate the phase of the static unbalance in the rotating coordinate system; the magnitude of the offset vector is calculated as... The magnitude of this offset vector indicates and calibrates the magnitude of the static imbalance of the rotating system.

7. The method for dynamic balance detection and analysis of a CT system based on detector data according to claim 6, characterized in that, ∆Y is determined by calculating the change in the number of channels covered by the projection of the rotation center offset trajectory of the rotation plane (XY) onto the detector (2) plane; ∆X is determined by calculating the position offset ∆Center of the projection of the rotation center offset trajectory of the rotation plane (XY) onto the detector (2) surface.

8. The method for dynamic balance detection and analysis of a CT system based on detector data according to claim 7, characterized in that, The difference between the even imbalance and static imbalance of the observed differential rotational speeds specifically includes: At relatively slow speeds, smaller effects of even and static imbalances are observed; at relatively fast speeds, larger effects of even and static imbalances are observed. The effects of different rotational speeds on centrifugal force were investigated by differentiating the effects of couple imbalance and static imbalance, and the phase and magnitude of the imbalance were observed accordingly. For even imbalance, the projection trajectory (5) data is scanned and obtained by low-speed rotation and high-speed rotation respectively. The spatial angle and phase between the plane normal vector of the spatial circular trajectory and the ideal rotation axis are identified, and finally the identification of even imbalance and the adjustment of its centroid plane are completed. For static imbalance, the projection trajectory (5) data is obtained by scanning with low speed and high speed rotation respectively, the center phase angle of the rotation center offset trajectory of the fan beam coordinate system (XY) and the rotation plane is identified, and finally the identification of static imbalance and its angular phase adjustment are completed.

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