Camera calibration method, device and system for standing position CT (Computed Tomography) equipment

Abstract

The invention discloses a camera calibration method, device and system for standing position CT equipment, the camera is any one of three depth cameras of the standing position CT equipment, and the three depth cameras are respectively located in front of and on two sides of the standing position CT equipment; the method comprises the steps that when a horizontal adjustment event of a first depth camera is detected, a simulation image of a standing detection system is output, and the simulation image at least comprises a first marker; the first depth camera is driven to move according to the received control signal, so that a preset position relation can be formed between a corresponding second marker on the tool and the first marker; wherein the tool is arranged on the inner side of the scanning frame, the tool is provided with a second marker corresponding to each depth camera, and each second marker is located in the camera shooting direction of each depth camera. According to the invention, the technical problem of inaccurate subsequent contour recognition caused by inaccurate installation position of the depth camera is solved.

Description

Technical Field

[0001] The present invention relates to the technical field of medical imaging, and in particular, to a camera calibration method, device, and system for a standing position CT device. Background Art

[0002] Most CT products use the horizontal position of the patient for examination. Due to the influence of gravity, when the human body is in the standing position and the lying position respectively, due to the difference in body position, the anatomical structure position changes, and the position and shape of the internal organs of the body will also change accordingly. The different forces on each part of the skeletal muscle system may cause changes in the morphological structure. Standing position CT refers to changing the patient's examination position from the original horizontal position to the standing or semi-sitting position of the patient, and changing the X-ray penetration by the medical device (scanner) that is stationary on the ground and rotates around the patient to the medical device (scanner) that simultaneously realizes linear motion along the patient's axis and rotational motion around the patient to realize X-ray penetration motion. Standing position CT examination can identify the true state of the human body in the weight-bearing position, especially for the spine and lower limbs, and is applied to the differential diagnosis of various diseases such as orthopedics and oncology.

[0003] In the vertical scanning device system, the patient stands on the patient support, and the system realizes the patient scanning process by raising the patient or moving the gantry. Due to the inaccurate installation position of the depth camera, the subsequent contour recognition is not accurate enough.

[0004] Aiming at the problem that the subsequent contour recognition is inaccurate due to the inaccurate installation position of the depth camera in the related technology, no effective solution has been proposed yet. Summary of the Invention

[0005] The main purpose of the present invention is to provide a camera calibration method, device, and system for a standing position CT device to solve the problem that the subsequent contour recognition is inaccurate due to the inaccurate installation position of the depth camera.

[0006] To achieve the above object, according to one aspect of the present invention, a camera calibration method for a standing position CT device is provided.

[0007] Camera calibration method for a standing position CT device according to the present invention. The camera is any one of the three depth cameras of the standing position CT device, and the three depth cameras are respectively located in the front and both sides of the standing position CT device. The method includes: when a horizontal adjustment event of the first depth camera is detected, output a simulated image of the standing detection system, where at least a first identifier is included in the simulated image; drive the first depth camera to move according to a received control signal, so that a corresponding second identifier on the tooling can form a preset positional relationship with the first identifier; where the tooling is arranged inside the scanning frame, and a second identifier is respectively arranged on the tooling corresponding to each depth camera, and each second identifier is respectively located in the imaging direction of each depth camera.

[0008] Further, before outputting the simulated image of the standing detection system, it further includes:

[0009] Receive the configured parameters of the scanning frame diameter and the safety circle diameter;

[0010] Determine the safe area and non-safe area of the standing detection system according to the scanning frame diameter and the safety circle diameter parameters;

[0011] When a camera safety test event is detected, retrieve the RGB image and depth image of the depth camera;

[0012] Test whether the RGB image and the depth image meet the safety detection conditions. If they meet, confirm that the camera environment calibration is successful.

[0013] Further, after controlling the depth camera to move until the second identifier on the corresponding tooling is aligned with the first identifier, the method further includes:

[0014] Calculate the height between four horizontal detection points in the rectangular detection frame of the camera image and the adjacent sides of the rectangular detection frame;

[0015] Judge whether the height error values between two-by-two heights meet the preset height error conditions;

[0016] If they meet, confirm that the depth camera is in a horizontal state.

[0017] Further, after judging whether the difference between two-by-two heights meets the preset height error conditions, it further includes:

[0018] If the height error conditions are not met, fine-tune the depth camera according to the difference between the two heights that do not meet the error conditions.

[0019] Further, after the step of confirming that the depth camera is in a horizontal state, it further includes:

[0020] Receive the installed heights and preset numbers of the three depth cameras configured.

[0021] When a camera height calibration event is detected, it is determined whether the measured height measured by the depth camera is the installation height;

[0022] If so, it is confirmed that the calibration is successful;

[0023] If the measured height is less than the installation height, it is confirmed that the calibration fails.

[0024] Further, three fourth markers are respectively arranged on the tooling corresponding to each of the depth cameras, and every three of the fourth markers are respectively located in the imaging direction of each of the depth cameras; after the step of confirming that the calibration is successful, the following steps are further included:

[0025] Call the position coordinates of the three depth cameras in the theoretical horizontal plane in the preset vertical CT coordinate system;

[0026] When a camera reverse verification event is detected, present draggable third markers corresponding to the actual horizontal positions of the three depth cameras in the theoretical horizontal plane in the simulated image;

[0027] Drag the three third markers respectively to align them with the corresponding fourth markers on the tooling;

[0028] Judge whether the horizontal error value determined according to the theoretical horizontal position coordinates and the actual horizontal position coordinates meets the preset horizontal error condition;

[0029] If it meets the requirement, it is confirmed that the reverse verification is up to standard.

[0030] To achieve the above object, according to another aspect of the present invention, a camera calibration device for a standing CT device is provided.

[0031] According to the camera calibration device for a standing CT device of the present invention, the camera is any one of the three depth cameras in the standing detection system of the standing CT device, and the three depth cameras are respectively located in the front and both sides of the standing CT device; the camera calibration device includes:

[0032] A simulated image output module, which outputs a simulated image of the standing detection system when a horizontal adjustment event of the first depth camera is detected, wherein the simulated image at least includes a first marker;

[0033] A first driving module, which is used to drive the first depth camera to move according to the received control signal, so that the corresponding second marker on the tooling can form a preset positional relationship with the first marker;

[0034] Among them, the tooling is arranged inside the scanning frame, and three second markers are respectively arranged on the tooling corresponding to each of the three depth cameras, and each second marker is respectively located in the imaging direction of each of the three depth cameras.

[0035] To achieve the above object, according to another aspect of the present invention, there is provided a camera calibration system for a standing position CT device.

[0036] The computer-readable storage medium according to the present invention includes tooling and the camera calibration device of the standing position CT device, and the calibration device is arranged in the controller of the standing position CT device.

[0037] In the embodiment of the present invention, a method of calibrating the position of the depth camera of the standing position CT device is adopted. When a horizontal adjustment event of the first depth camera is detected, a simulated image of the standing detection system is output, wherein the simulated image at least includes a first marker; driving the first depth camera to move according to the received control signal, so that the corresponding second marker on the tooling can form a preset positional relationship with the first marker; achieving the purpose of accurately adjusting the installation position of the depth camera, thereby realizing the technical effect of improving the subsequent contour recognition accuracy, and further solving the technical problem of inaccurate subsequent contour recognition caused by the inaccurate installation position of the depth camera. Description of the Drawings

[0038] The drawings constituting a part of the present invention are used to provide a further understanding of the present invention, making other features, objects, and advantages of the present invention more obvious. The schematic embodiments and descriptions of the present invention are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0039] Figure 1 is a flowchart of a camera calibration method for a standing position CT device according to an embodiment of the present invention;

[0040] Figure 2 is a construction diagram of a vertical CT coordinate system according to an embodiment of the present invention;

[0041] Figure 3 is a layout schematic diagram of a standing position CT device according to an embodiment of the present invention;

[0042] Figure 4 is a structural schematic diagram of a standing position CT device according to an embodiment of the present invention;

[0043] Figure 5 is a parameter configuration diagram according to an embodiment of the present invention;

[0044] Figure 6 is a camera safety test diagram according to an embodiment of the present invention;

[0045] Figure 7 is the camera parallel state inspection diagram according to an embodiment of the present invention;

[0046] Figure 8 is the camera height calibration diagram according to an embodiment of the present invention;

[0047] Figure 9 is the reverse verification diagram of the camera position according to an embodiment of the present invention;

[0048] Figure 10 is the reverse verification alignment operation diagram according to an embodiment of the present invention.

[0049] Reference numerals

[0050] 1. Standing position CT device; 2. Gantry; 3. Depth camera; 4. Tooling; 5. Backplane; 6. Safe area; 7. Non-safe area; 8. Outer ring of the gantry. Detailed implementation manners

[0051] In order to enable those skilled in the art of the present technology to better understand the solution of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0052] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and do not necessarily need to describe a specific order or sequence. It should be understood that such used data can be interchanged under appropriate circumstances so as to implement the embodiments of the present invention described herein. In addition, the terms "comprising" and "having" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product or device including a series of steps or units does not necessarily have to be limited to those clearly listed steps or units, but may include other steps or units not clearly listed or inherent to these processes, methods, products or devices.

[0053] In the present invention, the orientation or positional relationship indicated by terms such as "upper", "lower", "left", "right", "front", "rear", "top", "bottom", "inner", "outer", "middle", "vertical", "horizontal", "lateral", "longitudinal", etc. is based on the orientation or positional relationship shown in the accompanying drawings. These terms are mainly used to better describe the present invention and its embodiments, and are not used to limit that the indicated devices, elements or components must have a specific orientation or be constructed and operated in a specific orientation.

[0054] Moreover, in addition to being used to indicate orientation or positional relationships, some of the above terms may also be used to represent other meanings. For example, the term "upper" may also be used to represent a certain attachment relationship or connection relationship in some cases. For those of ordinary skill in the art, the specific meanings of these terms in the present invention can be understood according to specific circumstances.

[0055] In addition, the terms "installed", "set up", "equipped with", "connected", "linked", "socketed" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral structure; it can be a mechanical connection or an electrical connection; it can be directly connected, or indirectly connected through an intermediate medium, or there is internal communication between two devices, components or parts. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0056] It should be noted that, without conflict, the embodiments in the present invention and the features in the embodiments can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in conjunction with the embodiments.

[0057] According to an embodiment of the present invention, a method for calibrating a camera of a standing CT device 1 is provided. As Figure 1-4 shown, the camera is any one of the three depth cameras 3 of the standing CT device 1, and the three depth cameras 3 are respectively located in the front and on both sides of the standing CT device 1. This method is executed by the controller of the CT device (hereinafter referred to as the "host"), and includes the following steps S101 and S102.

[0058] S101. When a horizontal adjustment event of the first depth camera 3 is detected, output a simulated image of the standing detection system, and at least a first identifier is included in the simulated image;

[0059] S102. Drive the first depth camera 3 to move according to the received control signal, so that a corresponding second identifier on the tooling 4 can form a preset positional relationship with the first identifier. As Figure 3 viewed from the perspective, one second identifier is provided above, below and on the left side of the tooling 4 (not shown in the figure), and the second identifier is respectively located on the right hand side, left hand side and in front of the face of the human body model serving as the tooling 4 (not shown in the figure) from the perspective. Figure 2 Specifically, the camera horizontal adjustment event refers to

[0060] Figure 6 ​The "Start" button in; the first marker refers to the crosshair drawn on the simulated image; the second marker refers to the crosshair on the tooling 4; the simulated image refers to the light projected onto the camera lens; the shape of the tooling 4 is a mannequin, and the second marker is preset on the mannequin; the preset positional relationship means that the first marker and the second marker coincide (align). When the user clicks the start button, the host will detect the camera horizontal adjustment event. At this time, the host calls the preset program for processing and displays a simulated image with a red "crosshair" drawn in the center. The user needs to issue an instruction to control the movement of the depth camera 3 until the "crosshair" first marker of the simulated image coincides (aligns) with the corresponding second marker on the tooling 4 and then stops moving. Thus, the installation position adjustment of the camera is initially realized.

[0061] It should be understood that a back plate 5 is provided behind the tooling 4. Both the back plate 5 and the tooling 4 are located in the middle of the scanning frame 2. The back plate 5 is mainly used to support the human body to stand.

[0062] In the embodiment of the present invention, a method for calibrating the position of the depth camera 3 of the standing CT device 1 is adopted. When detecting a horizontal adjustment event of the first depth camera 3, a simulated image of the standing detection system is output, and the simulated image includes a first marker; driving the first depth camera 3 to move according to the received control signal so that the corresponding second marker on the tooling 4 can form a preset positional relationship with the first marker, such as coincidence between the two, or alternatively, a fixed distance and a relative direction between the two; achieving the purpose of accurately adjusting the installation position of the depth camera 3, thereby realizing the technical effect of improving the subsequent contour recognition accuracy, and further solving the technical problem of inaccurate subsequent contour recognition caused by the inaccurate installation position of the depth camera 3.

[0063] According to the embodiment of the present invention, before outputting the simulated image of the standing detection system, the host can first receive the parameters of the diameter of the scanning frame 2 and the diameter of the safety circle configured, and then determine the safety area 6 and the non-safety area 7 (the shaded part in the figure) of the standing detection system according to the parameters of the diameter of the scanning frame 2 and the diameter of the safety circle.

[0064] The user can Figure 4 set the parameters of the diameter of the scanning frame 2 (the diameter of the outer circle 8 of the scanning frame) and the diameter of the safety circle through the interface. The internal diameter of the scanning frame 2, that is, the maximum diameter of the detection area; in this embodiment, the internal diameter of the scanning frame 2 is mechanically designed to be 1000 mm. In order to reduce errors in this system, the detection range is set to be slightly smaller than the internal diameter of the scanning frame 2. The diameter of the safety circle, that is, the diameter of the safe area 6 where the patient stands. In this embodiment, according to the body types of ordinary people, it is objectively set to be 860 mm. After the setting is completed, the user can click Next to enter the self-calibration of the camera usage environment.

[0065] In the embodiment of the present invention, before adjusting each depth camera 3, environmental adjustment can be performed first. That is to say, when a camera safety test event is detected, the RGB image and depth image of the depth camera 3 are retrieved; it is tested whether the RGB image and depth image meet the safety detection conditions; if they meet, it is confirmed that the camera environment calibration is successful.

[0066] Specifically, affected by external environments such as light, the camera needs to self-check whether its operating environment meets its operating conditions. The camera safety test event refers to Figure 5 the "Start" button in ; after clicking the "Start" button, the host retrieves the RGB image and depth image of the depth camera 3 for camera self-check, that is, it is tested whether the RGB image and depth image meet the safety detection conditions; if this condition is met, "Success" is prompted, if not, "Failure" is prompted. When "Failure" is prompted, the user needs to debug the light conditions of the environment. When "Success" is prompted, click the "Next" button to enter the camera position adjustment.

[0067] According to the embodiment of the present invention, after controlling the depth camera 3 to move until the second marker on the corresponding tooling 4 is aligned with the first marker, horizontal calibration is still required; that is, the heights from the four horizontal detection points in the rectangular detection frame of the camera image to the adjacent sides of the rectangular detection frame are calculated; it is judged whether the height error values between the pairwise heights meet the preset height error conditions; if they meet, it is confirmed that the depth camera 3 is in a horizontal state.

[0068] Specifically, please refer to Figure 6 , after the camera position adjustment is completed, a rectangular frame is drawn in the center of the simulated image, and four points for measuring distances are drawn on the top, bottom, left, and right in the rectangular frame. The heights from the horizontal detection points to the adjacent sides of the rectangular detection frame are measured, and height comparisons are made between all pairwise heights. Excluding the errors of the camera itself, if the height differences between the four points are less than 5 mm, it is considered that the installation position of the camera is in a horizontal state. The horizontal state inspection of the depth camera 3 is realized.

[0069] According to the embodiment of the present invention, after judging whether the difference between the pairwise heights meets the preset height error conditions, it further includes: if the height error conditions are not met, the depth camera 3 is finely adjusted according to the difference between the two heights that do not meet the error conditions.

[0070] Specifically, through the horizontal state inspection of the depth camera 3, it can be determined whether the depth camera 3 is in a horizontal state. If not, the host can call the fine-tuning program to finely adjust the depth camera 3 according to the difference between the two heights that do not meet the error conditions, and then perform the horizontal state inspection until the calibration is successful. Through the calibration, the adjustment of the horizontal state of the depth camera 3 is realized, which can improve the accuracy of the installation position of the depth camera 3, and thus further improve the accuracy of contour recognition.

[0071] In addition, when the error condition is not met, the user can manually control the depth camera 3 for fine-tuning.

[0072] According to an embodiment of the present invention, after the step of confirming that the depth camera 3 is in a horizontal state, the method further includes: receiving the installation heights and preset numbers of the three configured depth cameras 3; when a camera height calibration event is detected, determining whether the measured height measured by the depth camera 3 is the installation height; if so, confirming that the calibration is successful; if the measured height is less than the installation height, confirming that the calibration fails.

[0073] Specifically, referring to Figure 7 , the purpose of setting the height of the camera is that when all "pixel points" in the detection area are in a safe state, the height measured by the camera is the installation height of the camera, then it is determined that the calibration is successful; if the height measured by a certain "pixel point" is less than the currently set height, it means that there is an object in this area and the calibration fails; the purpose of setting the camera numbers is that the three cameras are responsible for different detection areas and it is necessary to show which area is in a dangerous situation (the detection areas of the three cameras partially overlap). When a calibration failure occurs, fine-tuning can be performed according to a preset fine-tuning procedure, or the user can manually adjust the horizontal state. By combining height calibration with position adjustment, the height positions of the three depth cameras 3 can be kept consistent, making the height positions of the three cameras more accurate, thereby further improving the accuracy of contour recognition.

[0074] According to an embodiment of the present invention, three fourth markers are respectively arranged on the tooling 4 corresponding to each depth camera 3, and every three of the fourth markers are respectively located in the imaging directions of each depth camera 3; after the step of confirming that the calibration is successful, the method further includes: calling the position coordinates of the three depth cameras 3 in the theoretical horizontal plane in the preset vertical CT coordinate system; when a camera reverse verification event is detected, presenting three draggable third markers corresponding to the actual horizontal positions of the three depth cameras 3 in the theoretical horizontal plane in the simulated image; respectively dragging the three third markers so that they respectively form a preset positional relationship with the corresponding fourth markers on the tooling 4; determining whether the horizontal error value determined according to the theoretical horizontal position coordinates and the actual horizontal position coordinates meets a preset horizontal error condition; if it meets, confirming that the reverse verification is up to standard.

[0075] Specifically, it can be referred to Figure 8 and Figure 9, after adjusting the height and level of the camera, it is also necessary to adjust the horizontal position where the camera is located; for this purpose, a camera reverse verification method is also set up, and through this method, the accuracy of the camera's horizontal position can be verified. Specifically, three draggable red crosshairs are drawn on the simulated image, and the red crosshairs are moved to coincide (align) with the corresponding crosshairs on the tooling 4 in the camera. The "coordinate point" calculation value is displayed on the interface, and then subtracted from the preset theoretical coordinate value to obtain the error value. Similarly, excluding the error range based on the camera ranging itself, the error range of the reverse verification should also be less than 5 mm. Through the reverse verification and the position adjustment, the horizontal position coordinates of the three depth cameras 3 can be made consistent with the theoretical horizontal position coordinates, making the horizontal positions of the three cameras more accurate, thereby further improving the accuracy of contour recognition.

[0076] Obviously, those skilled in the art should understand that the above-mentioned modules or steps of the present invention can be implemented by a general-purpose computing device. They can be concentrated on a single computing device or distributed on a network composed of multiple computing devices. Optionally, they can be implemented by program codes executable by the computing device. Thus, they can be stored in a storage device and executed by the computing device, or they can be separately fabricated into individual integrated circuit modules, or multiple modules or steps among them can be fabricated into a single integrated circuit module to implement. In this way, the present invention is not limited to any specific combination of hardware and software.

[0077] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention can have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A camera calibration method for a standing position CT device, where the camera is any one of the three depth cameras of the standing position CT device, and the three depth cameras are respectively located in the front and both sides of the standing position CT device; characterized in that, The method includes: When a horizontal adjustment event of the first depth camera is detected, output a simulated image of the standing detection system, where at least a first identifier is included in the simulated image; Drive the first depth camera to move according to the received control signal, so that a corresponding second identifier on the tooling can form a preset positional relationship with the first identifier; Wherein, the tooling is arranged inside the scanning frame, and a second identifier is respectively arranged on the tooling corresponding to each depth camera, and each second identifier is respectively located in the imaging direction of each depth camera.

2. The camera calibration method according to claim 1, wherein Before outputting the simulated image of the standing detection system, it further includes: Receive the configured parameters of the scanning frame diameter and the safety circle diameter; Determine the safe area and non-safe area of the standing detection system according to the scanning frame diameter and the safety circle diameter parameters; When a camera safety test event is detected, retrieve the RGB image and depth image of the depth camera; Test whether the RGB image and the depth image meet the safety detection conditions, and if so, confirm that the camera environment calibration is successful.

3. The camera calibration method according to claim 1, characterized in that, After controlling the depth camera to move until the second identifier on the corresponding tooling is aligned with the first identifier, the method further includes: Calculate the height between four horizontal detection points in the rectangular detection frame of the camera image and the adjacent sides of the rectangular detection frame; Judge whether the height error values between two-by-two heights meet the preset height error conditions; If so, confirm that the depth camera is in a horizontal state.

4. The camera calibration method according to claim 3, wherein After judging whether the difference between two-by-two heights meets the preset height error conditions, it further includes: If the height error conditions are not met, fine-tune the depth camera according to the difference between the two heights that do not meet the error conditions.

5. The camera calibration method according to claim 3, characterized in that After the step of confirming that the depth camera is in a horizontal state, it further includes: Receive the installed heights and preset numbers of the three depth cameras configured; When a camera height calibration event is detected, judge whether the measured height measured by the depth camera is the installed height; If so, confirm that the calibration is successful; If the measured height is less than the installed height, confirm that the calibration fails.

6. The camera calibration method according to claim 5, wherein Three fourth identifiers are respectively arranged on the tooling corresponding to each depth camera, and every three fourth identifiers are respectively located in the imaging direction of each depth camera; After the step of confirming that the calibration is successful, it further includes: Call the position coordinates of the three depth cameras in the theoretical horizontal plane in the preset vertical CT coordinate system; When a camera reverse verification event is detected, present draggable third identifiers corresponding to the actual horizontal positions of the three depth cameras in the theoretical horizontal plane in the simulated image; Drag the three third identifiers respectively so that they respectively form a preset positional relationship with the corresponding fourth identifiers on the tooling; Judge whether the horizontal error value determined according to the theoretical horizontal position coordinates and the actual horizontal position coordinates meets the preset horizontal error conditions; If so, confirm that the reverse verification is up to standard.

7. A camera calibration device for a standing position CT device, characterized in that, This camera is any one of the three depth cameras in the standing detection system of a standing position CT device, and the three depth cameras are respectively located in the front and both sides of the standing position CT device; characterized in that, the camera calibration device includes: The analog image output module outputs an analog image of the standing detection system when a horizontal adjustment event of the first depth camera is detected, wherein the analog image at least includes a first identifier; The first driving module is configured to drive the first depth camera to move according to the received control signal, so that a corresponding second identifier on the tooling can form a preset positional relationship with the first identifier; Wherein, the tooling is arranged in the scanning frame, and three second identifiers are respectively arranged on the tooling corresponding to each of the three depth cameras, and each second identifier is respectively located in the imaging direction of each of the three depth cameras.

8. A camera calibration system for a standing position CT device, characterized in that, It includes a tooling and the camera calibration device of the standing position CT device according to claim 7, and the calibration device is arranged in the controller of the standing position CT device.

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