CN104698016A - Multi-time horizontal movement staggered spiral industrial CT scanning imaging method - Google Patents
Multi-time horizontal movement staggered spiral industrial CT scanning imaging method Download PDFInfo
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- CN104698016A CN104698016A CN201510137023.1A CN201510137023A CN104698016A CN 104698016 A CN104698016 A CN 104698016A CN 201510137023 A CN201510137023 A CN 201510137023A CN 104698016 A CN104698016 A CN 104698016A
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Abstract
The invention relates to a multi-time horizontal movement staggered spiral industrial CT scanning imaging method, and belongs to the technical field of CT scanning. The method comprises the steps that in the scanning period, a carrying rotary table rotates in one direction all the time, the rotary table only needs to transversely horizontally move in the direction parallel to a detector at the two-time spiral scanning interval and does not need to move in the radial direction, and staggered spiral scanning is achieved through a radiation source and the axial reciprocating movement of the detector. The multi-time horizontal movement staggered spiral industrial CT scanning imaging method is suitable for high-precision and rapid three-dimensional imaging of a III generation CT large-size workpiece. High-precision and rapid three-dimensional imaging is achieved through a III generation linear array detector CT system, the detector physical interpolation is not needed in the scanning process, the structure of the CT system is simplified on the premise that the detection precision is guaranteed, the manufacturing cost of the CT system is reduced, and the detecting efficiency is effectively improved.
Description
Technical field
The invention belongs to CT scan technical field, relate to a kind of interlaced helical industry CT scan imaging method of repeatedly translation.
Background technology
Be limited to volume and the cost of detector, the main layout of current large-scale high energy ICT equipment is still II generation, III generation or II+III generation, and detector is linear array detector substantially, seldom has planar array detector.Therefore detection efficiency is lower, and the cost of detection is higher.High energy CT reduces the crosstalk between detector, generally first to carry out ray collimation by " tunnel type " collimating apparatus before ray enters detector, because every 1 detector cells all needs the collimating apparatus that corresponds, objectively cause unit length detector quantity few, single detector cost is high, cannot large-scale integrated be carried out.When not increasing detection density, for improving the spatial resolution of CT, conventional method carries out physics interpolation (in scanning process, by the swing of detector or the movement of object, obtain Multiple-Scan data, then these data are combined into fan-beam data).If surveyed area is not a tomography, but certain scope, conventional method successively scans, and due to the relation of testing cost, interfloor distance is generally larger.Between two-layer scanning, accelerator needs to stop bundle (because the life-span of accelerator is limited, the life-span of its core component is at 500 ~ 800 hours), and thus detection efficiency is lower.
Summary of the invention
In view of this, the object of the present invention is to provide a kind of interlaced helical industry CT scan imaging method of repeatedly translation, the method, in the spatial resolution situation ensureing CT, can improve detection efficiency, reduces testing cost.
For achieving the above object, the invention provides following technical scheme:
A repeatedly interlaced helical industry CT scan imaging method for translation, the method comprises the following steps:
S1: workpiece for measurement is placed on scanning turntable, according to testing requirement, workpiece for measurement is fixed;
S2: the visual field size of CT scan, detecting distance and imaging size detected parameters are set according to testing requirement; The pitch and the scanning turntable translation step pitch that calculate CT scan is required according to detected parameters;
S3: according to detector size, imaging size, sampling time, determines radiographic source, detector is synchronized with the movement speed and detection platform rotational speed;
S4: by radiographic source, detector synchronizing moving to the bottom in region of object to be scanned, carry out radiographic source simultaneously, detector is synchronized with the movement and scans turntable rotary motion;
S5: namely complete first time spiral scan after being synchronized with the movement and exceeding sensing range until radiographic source, detector; Stopping radiographic source, detector are synchronized with the movement, and will scan turntable translation step pitch, without the need to stopping the rotary motion of turntable in translation motion;
S6: the scanning workpiece for measurement again that radiographic source, detector is synchronized with the movement round about completes second time spiral scan;
S7: repeat S5, S6, until scanning turntable translation N-1 step, completes whole spiral scan; N is for determine to need to do N spiral scan according to detected parameters;
S8: the data for projection that S4 and S6 collects is reset;
S9: CT image reconstruction is carried out to the data acquisition iterative reconstruction algorithm after S8 resets.
Further, the step pitch of described scanning turntable translation is,
Wherein, R is the radius of curved detector, and the angle of two adjacent detector unit is △ γ.
Further, the method that in described S8, data for projection carries out resetting is, rebuilding the projected angle scope of layer is limited in a less scope, the projected angle scope that accelerator CT rebuilds layer is 12 °-18 °, the projected angle scope that bulb machine CT rebuilds layer is 30 °-40 °, adopts finite angle method for reconstructing to carry out CT image reconstruction.
Further, described S9 adopts iterative reconstruction algorithm to carry out CT image reconstruction, and concrete steps are: adopt TV regularization method to each spiral reconstruction, then all results superposed, then stack result corrected; Prior imformation is introduced in algorithm realization process; Purpose parallel acceleration algorithm is adopted to realize Fast Reconstruction.
Beneficial effect of the present invention is: the interlaced helical industry CT scan imaging method of a kind of repeatedly translation provided by the invention, the scan mode of existing three generations's linear array spiral CT machine is transformed, eliminate detector physics interpolation structure, substitute with scan table translation and realize image interpolation, reduce the hardware cost of CT machine; Adopt object under test continuous rotation, detector and the radiographic source mode of being synchronized with the movement to realize interlaced helix scan path in scanning, improve scan efficiency, reduce CT testing cost; Image reconstruction adopts that TV method of regularization is high in conjunction with priori, reconstruction quality, good resolution.
Accompanying drawing explanation
In order to make the object, technical solutions and advantages of the present invention clearly, below in conjunction with accompanying drawing, the present invention is described in further detail, wherein:
Fig. 1 is the process flow diagram of the method for the invention;
Fig. 2 is twice spiral three-dimensional schematic diagram;
Fig. 3 is twice spiral three-dimensional vertical view;
Fig. 4 is the translation schematic diagram of four physics interpolation.
Embodiment
Below in conjunction with accompanying drawing, the preferred embodiments of the present invention are described in detail.
The interlaced helical industry CT scan imaging method of a kind of repeatedly translation provided by the invention, the flow process of the method as shown in Figure 1.Be equivalent to radiographic source and the detector platform that rotates be rotated counterclockwise because Objects around A turntable turns clockwise, similarly, Objects around A turntable is rotated counterclockwise and is equivalent to radiographic source and the detector platform that rotates and turns clockwise, for convenience of description, following description is all that hypothesis object maintains static, radiographic source and the detector platform that rotates rotates, and supposes that radiographic source and detector are along turntable axial translation simultaneously.Following describes the scanning theory illustrating interlaced helical with No. 4 turntable translations.Said method comprising the steps of:
S1: workpiece for measurement is placed on scanning turntable, according to testing requirement to workpiece carry out necessary fixing with prevent workpiece rotate and translation time there is change in location;
S2: according to testing requirement, the visual field size of CT scan, source are set to the distance of object rotation center, rotation center to detected parameters such as the distance of detector and imaging sizes, require that (i.e. imaging space resolution) calculates the pitch of CT scan and scans turntable translation step pitch according to detected parameters;
Fig. 2 is first time and the second time structure of spiral scan and vertical view thereof, when Fig. 3 is 4 spiral scan, and the schematic diagram of beam corresponding to a probe unit in the vertical view of initial angle or end angle.
Suppose that the angle of two adjacent detector unit is △ γ, then radiographic source and each translation distance of detector (namely scanning the step pitch of turntable translation) are
This distance is determined by the number of times of translation.Wherein R is the radius of curved detector.
S3: according to detector size, imaging size sampling time, determine radiographic source, detector is synchronized with the movement speed and detection platform rotational speed;
S4: by radiographic source, detector synchronizing moving to the bottom in the region to be measured of scanning object, open radiographic source; Until radiographic source go out after Shu Wending carry out radiographic source simultaneously, detector is synchronized with the movement and scans turntable rotary motion;
S5: namely complete first time spiral scan after being synchronized with the movement and exceeding sensing range until radiographic source, detector, stopping radiographic source, detector are synchronized with the movement, turntable translation step pitch will be scanned, without the need to stopping the rotary motion of turntable and keeping radiographic source opening in translation motion;
S6: the scanning workpiece for measurement again that radiographic source, detector is synchronized with the movement round about completes second time spiral scan;
S7: repeat S5, S6, until scanning turntable translation N-1 step, completes whole spiral scan; N is for determine to need to do N spiral scan according to detected parameters;
Suppose that region to be detected is time-limited cylindrical, with its center foundation rectangular coordinate system o-xyz as shown in Figure 1, according to Fig. 2 and Fig. 3, the scanning process of interlaced helical be described below: in testing process, radiographic source and detector are first along the negative semiaxis translation of direction to y-axis being parallel to y-axis
then radiographic source and detector turn clockwise around object, and radiographic source and detector edge are parallel to moving up of the direction of z-axis simultaneously, obtain first time spiral scan; Radiographic source and detector continue to be rotated in a clockwise direction, radiographic source and detector are again along the direction being parallel to y-axis to the positive axis translation △ d of y-axis as shown in Figure 4, then radiographic source and detector edge are parallel to moving down of the direction of z-axis, obtain second time spiral scan; Similar fashion carries out third time and the 4th spiral scan according to this.
S8: the data for projection that S4 and S6 collects is reset;
The method that data for projection carries out resetting is: be limited in a less scope by rebuilding the projected angle scope of layer, the projected angle scope that accelerator CT rebuilds layer is 12 °-18 °, the projected angle scope that bulb machine CT rebuilds layer is 30 °-40 °, instead of traditional 180 ° or 360 °, adopt finite angle method for reconstructing to carry out CT image reconstruction.
S9: CT image reconstruction is carried out to the data acquisition iterative reconstruction algorithm after S8 resets.
Iterative reconstruction algorithm carries out CT image reconstruction, and concrete steps are: adopt TV regularization method to each spiral reconstruction, then all results superposed, then stack result corrected; Prior imformation is introduced in algorithm realization process; Purpose parallel acceleration algorithm is adopted to realize Fast Reconstruction.
From above-mentioned description process, in testing process, consider some specific detected object, as solid propellant rocket etc., can only rotate around a direction, radiographic source and detector rotate around object clockwise direction all the time, and radiographic source and detector need to do a translation motion between twice spiral scan, define interlaced helical structure by radiographic source and detector along the direction upper and lower translation being parallel to turret axis.In the image reconstruction stage, owing to have employed the reconstruction algorithm of improvement, only need the direction knowing each initial angle, sweep length, pitch and the axial translation that rotate, consider in most cases, turntable can not radial translation, the method of the invention does not need turntable radial translation, turntable is not needed to get back to reference position in next time before scanning yet, more crucially accelerator only need scanning start and at the end of switch once, centre does not need to stop bundle, thus improve detection efficiency, save testing cost.Meanwhile, this scan mode does not need detector to carry out physics interpolation, simplifies physical construction and the control algolithm of CT system, effectively reduces the cost of CT system.
What finally illustrate is, above preferred embodiment is only in order to illustrate technical scheme of the present invention and unrestricted, although by above preferred embodiment to invention has been detailed description, but those skilled in the art are to be understood that, various change can be made to it in the form and details, and not depart from claims of the present invention limited range.
Claims (4)
1. an interlaced helical industry CT scan imaging method for repeatedly translation, is characterized in that: the method comprises the following steps:
S1: workpiece for measurement is placed on scanning turntable, according to testing requirement, workpiece for measurement is fixed;
S2: the visual field size of CT scan, detecting distance and imaging size detected parameters are set according to testing requirement; The pitch and the scanning turntable translation step pitch that calculate CT scan is required according to detected parameters;
S3: according to detector size, imaging size, sampling time, determines radiographic source, detector is synchronized with the movement speed and detection platform rotational speed;
S4: by radiographic source, detector synchronizing moving to the bottom in region of object to be scanned, carry out radiographic source simultaneously, detector is synchronized with the movement and scans turntable rotary motion;
S5: namely complete first time spiral scan after being synchronized with the movement and exceeding sensing range until radiographic source, detector; Stopping radiographic source, detector are synchronized with the movement, and will scan turntable translation step pitch, without the need to stopping the rotary motion of turntable in translation motion;
S6: the scanning workpiece for measurement again that radiographic source, detector is synchronized with the movement round about completes second time spiral scan;
S7: repeat S5, S6, until scanning turntable translation N-1 step, completes whole spiral scan; N is for determine to need to do N spiral scan according to detected parameters;
S8: the data for projection that S4 and S6 collects is reset;
S9: CT image reconstruction is carried out to the data acquisition iterative reconstruction algorithm after S8 resets.
2. the interlaced helical industry CT scan imaging method of a kind of repeatedly translation according to claim 1, is characterized in that: the step pitch of described scanning turntable translation is,
Wherein, R is the radius of curved detector, and the angle of two adjacent detector unit is △ γ.
3. the interlaced helical industry CT scan imaging method of a kind of repeatedly translation according to claim 1, it is characterized in that: the method that in described S8, data for projection carries out resetting is, the projected angle scope of rebuilding layer is limited in less scope, the projected angle scope that accelerator CT rebuilds layer is 12 °-18 °, the projected angle scope that bulb machine CT rebuilds layer is 30 °-40 °, adopts finite angle method for reconstructing to carry out CT image reconstruction.
4. the interlaced helical industry CT scan imaging method of a kind of repeatedly translation according to claim 1, it is characterized in that: described S9 adopts iterative reconstruction algorithm to carry out CT image reconstruction, concrete steps are: adopt TV regularization method to each spiral reconstruction, then all results are superposed, then stack result is corrected; Prior imformation is introduced in algorithm realization process; Purpose parallel acceleration algorithm is adopted to realize rebuilding.
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Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105136823A (en) * | 2015-07-07 | 2015-12-09 | 重庆大学 | Large diameter pipeline wall outside CT local scanning imaging method |
| CN105445300A (en) * | 2015-12-16 | 2016-03-30 | 天津三英精密仪器有限公司 | Full-field rod-shaped sample CT scanning device |
| CN106691488A (en) * | 2017-01-25 | 2017-05-24 | 重庆大学 | Spiral CT scanning and image-forming method and system |
| CN107764846A (en) * | 2017-10-20 | 2018-03-06 | 重庆大学 | A kind of the CL imaging systems and analysis method of orthogonal straight lines scanning |
| CN114713518A (en) * | 2022-03-15 | 2022-07-08 | 江苏纳唯信息技术有限公司 | Intelligent flaw detection method for inner wall of industrial pipe fitting based on image analysis |
| CN115113289A (en) * | 2021-07-07 | 2022-09-27 | 同方威视技术股份有限公司 | Inspection system and method |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5463666A (en) * | 1993-11-12 | 1995-10-31 | General Electric Company | Helical and circle scan region of interest computerized tomography |
| US5805659A (en) * | 1996-09-30 | 1998-09-08 | Siemens Corporate Research, Inc. | Method and apparatus for spiral scan region of interest imaging |
| US5878103A (en) * | 1997-06-30 | 1999-03-02 | Siemens Corporate Research, Inc. | Adaptive detector masking for speed-up of cone beam reconstruction |
| CN101393145A (en) * | 2008-10-22 | 2009-03-25 | 重庆大学 | Cone beam double-helix CT Scanning and imaging method for large sized object |
| CN103163165A (en) * | 2013-02-28 | 2013-06-19 | 重庆大学 | Second generation computed tomography (CT) scanning imaging method |
-
2015
- 2015-03-26 CN CN201510137023.1A patent/CN104698016B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5463666A (en) * | 1993-11-12 | 1995-10-31 | General Electric Company | Helical and circle scan region of interest computerized tomography |
| US5805659A (en) * | 1996-09-30 | 1998-09-08 | Siemens Corporate Research, Inc. | Method and apparatus for spiral scan region of interest imaging |
| US5878103A (en) * | 1997-06-30 | 1999-03-02 | Siemens Corporate Research, Inc. | Adaptive detector masking for speed-up of cone beam reconstruction |
| CN101393145A (en) * | 2008-10-22 | 2009-03-25 | 重庆大学 | Cone beam double-helix CT Scanning and imaging method for large sized object |
| CN103163165A (en) * | 2013-02-28 | 2013-06-19 | 重庆大学 | Second generation computed tomography (CT) scanning imaging method |
Non-Patent Citations (1)
| Title |
|---|
| 王珏 等: "安全检查用螺旋CT扫描同步控制研究", 《核电子学与探测技术》 * |
Cited By (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105136823A (en) * | 2015-07-07 | 2015-12-09 | 重庆大学 | Large diameter pipeline wall outside CT local scanning imaging method |
| CN105136823B (en) * | 2015-07-07 | 2017-12-05 | 重庆大学 | CT partial sweep imaging methods outside large diameter pipeline wall |
| CN105445300A (en) * | 2015-12-16 | 2016-03-30 | 天津三英精密仪器有限公司 | Full-field rod-shaped sample CT scanning device |
| CN106691488A (en) * | 2017-01-25 | 2017-05-24 | 重庆大学 | Spiral CT scanning and image-forming method and system |
| CN106691488B (en) * | 2017-01-25 | 2019-10-18 | 重庆大学 | CT scan imaging method and system |
| CN107764846A (en) * | 2017-10-20 | 2018-03-06 | 重庆大学 | A kind of the CL imaging systems and analysis method of orthogonal straight lines scanning |
| CN107764846B (en) * | 2017-10-20 | 2020-04-14 | 重庆大学 | Orthogonal linear scanning CL imaging system and analysis method |
| CN115113289A (en) * | 2021-07-07 | 2022-09-27 | 同方威视技术股份有限公司 | Inspection system and method |
| CN115113289B (en) * | 2021-07-07 | 2024-04-26 | 同方威视技术股份有限公司 | Inspection system and method |
| CN114713518A (en) * | 2022-03-15 | 2022-07-08 | 江苏纳唯信息技术有限公司 | Intelligent flaw detection method for inner wall of industrial pipe fitting based on image analysis |
| CN114713518B (en) * | 2022-03-15 | 2024-05-14 | 江苏纳唯信息技术有限公司 | Intelligent flaw detection method for inner wall of industrial pipe fitting based on image analysis |
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