Radiation generator

Abstract

The present invention provides a radiation generating device that can contribute to high-precision alignment between a radiation source and a radiation image detection device. [Solution] The radiation generating device has a main body to which an arm holding a radiation source that emits radiation toward the patient is attached, and this main body is mounted on a cart with wheels. The radiation generating device is equipped with a rotation mechanism that allows the main body to rotate around a vertical axis relative to the cart.

Description

[[Technical Field]]

[0001] The technology of the present disclosure relates to a radiation generating apparatus. [[Background Art]]

[0002] In medical practice, a mobile radiation generating apparatus is used, in which a main body having a radiation source that emits radiation toward a subject is mounted on a carriage portion having wheels. For example, the mobile radiation generating apparatus is used for so-called round imaging, in which imaging of a patient as a subject is performed while moving between hospital rooms.

[0003] As such a mobile radiation generating apparatus, for example, Patent Document 1 is disclosed. In the mobile radiation generating apparatus described in Patent Document 1, an arm that holds a radiation source at its distal end is attached to the main body. The arm is rotatable about a vertical axis with respect to the main body. [[Prior Art Documents]] [[Patent Documents]]

[0004] [[Patent Document 1]] Japanese Unexamined Patent Publication No. 2017-119173 [[Summary of the Invention]] [[Problem to be Solved by the Invention]]

[0005] When the mobile radiation generating apparatus reaches a target position beside a supine imaging table (bed) for example, the radiation source may be arranged inclined with respect to a radiation image detection device such as an electronic cassette when viewed from above. In such a case, it is necessary to rotate the arm about the vertical axis with respect to the main body to eliminate the inclination. However, the radiation source has a relatively large weight of several kilograms, and when the arm holding such a radiation source at the distal end is rotated, there is a risk that the main body moves due to reaction, or the arm does not stop at an intended position due to inertia.

[0006] One embodiment of the technology described herein provides a radiation generator capable of contributing to high-precision alignment between a radiation source and a radiation image detection device. [Means for solving the problem]

[0007] The radiation generating device of this disclosure is a radiation generating device in which a main body portion, to which an arm that holds a radiation source that emits radiation toward a subject is attached, is mounted on a trolley portion having wheels, and the main body portion is provided with a rotation mechanism that allows the main body portion to rotate about a vertical axis relative to the trolley portion.

[0008] It is preferable to have a first locking mechanism that can lock the rotation of the main body.

[0009] It is preferable that the lock by the first locking mechanism is released when the setting conditions are met.

[0010] It is preferable that the lock by the first locking mechanism is released when the current position becomes the target position.

[0011] Preferably, the system includes an environmental information sensor and a processor, and the processor creates a map of the surrounding environment while estimating its own position from the output data of the environmental information sensor.

[0012] It is preferable that the vehicle is capable of autonomous driving based on map data.

[0013] Preferably, the system is equipped with a camera, and the lock by the first locking mechanism is released when the radiation image detection device or the subject is detected in the camera's image.

[0014] It is preferable that the lock by the first locking mechanism is released when an operation instruction to release the lock is entered.

[0015] The trolley section preferably has a second locking mechanism that can lock the rotation of the wheels.

[0016] It is preferable that locking by the second locking mechanism is performed when locking by the first locking mechanism is released.

[0017] It is preferable that the first locking mechanism is an electromagnetic brake.

[0018] It is preferable that the radiation generating apparatus includes a processor, and the processor controls rotation of the main body portion by the rotation mechanism based on an inclination angle among the radiation source, the radiation image detecting apparatus, an imaging table, or a subject.

[0019] It is preferable that the processor derives, as the inclination angle, a difference between an azimuth angle of the radiation source detected by a geomagnetic sensor and an azimuth angle of the imaging table.

[0020] It is preferable that a first magnet is provided on the main body portion, and positioning between the radiation source and the imaging table is performed by the first magnet being attracted to a second magnet provided on the imaging table.

[0021] It is preferable that the rotation mechanism rotates around a vertical axis passing through at least one of a center of the main body portion or a focal point of radiation.

Effects of the Invention

[0022] According to the technology of the present disclosure, it is possible to provide a radiation generating apparatus that can contribute to highly accurate positioning between a radiation source and a radiation image detecting apparatus.

Brief Description of Drawings

[0023] [Figure 1] Fig. 1 is a diagram showing a state of supine-position imaging using a radiation imaging system. [Figure 2] Fig. 2 is a diagram showing a state of standing-position imaging using a radiation imaging system. [Figure 3] Fig. 3 is a diagram showing the rotation mechanism and the first locking mechanism. [Figure 4] Fig. 4 is a block diagram showing an electrical configuration of the radiation generating apparatus and the second locking mechanism. [Figure 5]This diagram shows the radiation generator moving from its standby position towards the first target position for supine imaging, and then stopping at the first target position. [Figure 6] This diagram shows the radiation generator moving from its standby position towards the second target position in standing imaging, and then stopping at the second target position. [Figure 7] This diagram shows the processing of each processing unit in the processor related to driving control. [Figure 8] This diagram shows the processing of each processing unit in the processor related to driving control. [Figure 9] This diagram shows that when the vehicle's own position becomes the target position, it transitions from driving control to alignment control, releasing the lock on the rotation of the main body by the first locking mechanism and locking the wheels by the second locking mechanism. [Figure 10] This diagram shows the processing of each processing unit in the processor related to alignment control. [Figure 11] This figure shows the processing during the training phase of the cassette contour extraction model. [Figure 12] This diagram shows the alignment control process. [Figure 13] This is a flowchart showing the shooting procedure. [Figure 14] This diagram shows that when an electronic cassette is detected from the alignment control image, the system switches from driving control to alignment control, the lock on the rotation of the main body by the first locking mechanism is released, and the wheels are locked by the second locking mechanism. [Figure 15] This diagram shows that when a patient is detected from the position control image, the system switches from travel control to position control, the first locking mechanism releases the rotation lock on the main body, and the second locking mechanism locks the wheels. [Figure 16] This diagram shows that when the rotation lock release button is operated, the rotation lock on the main body by the first locking mechanism is released, and the wheels are locked by the second locking mechanism. [Figure 17] This figure shows a method for extracting a patient's joint points from an image used for alignment control. [Figure 18] This figure shows the angle of inclination in the embodiment shown in Figure 17. [Figure 19] This diagram shows a method for detecting the tilt angle based on the azimuth angle detection result from a geomagnetic sensor. [Figure 20] This diagram shows a method for detecting the tilt angle based on the azimuth angle detection result from a geomagnetic sensor. [Figure 21] This diagram shows a method of aligning a radiation source with a supine imaging table using magnets. [Figure 22] This diagram shows the main body being rotated around a vertical axis passing through the focal point of the radiation. [Figure 23] This is a diagram showing a medical examination table with a rotating mechanism. [Modes for carrying out the invention]

[0024] [First Embodiment] As an example, as shown in Figures 1 and 2, the radiography system 10 comprises a radiation generator 11 and an electronic cassette 12. The radiation generator 11 has a main body 14 having a radiation source 13 that emits radiation R toward the patient P, mounted on a trolley 16 having wheels 15. The radiation R is, for example, X-rays. The radiation generator 11 is equipped with a battery and can be powered by the battery. The radiation generator 11 can also be powered by a commercial power supply via a power cord. The electronic cassette 12 is an example of a "radiation image detection device" related to the technology of this disclosure. The patient P is an example of a "subject" related to the technology of this disclosure.

[0025] The radiation generator 11 is movable within the imaging room RM (see also Figures 5 and 6). The radiation generator 11 is also used for so-called mobile imaging, where images are taken of patients P while moving around the patient rooms. For this reason, the radiation generator 11 is also called a mobile imaging unit. Alternatively, the radiation generator 11 can be used for imaging in the emergency room. Furthermore, the radiation generator 11 can be brought into the operating room and used during surgery.

[0026] The electronic cassette 12 has a configuration in which a sensor panel, which acts as a radiation detector for detecting radiation R, is built into a portable housing. The electronic cassette 12 is powered by a battery and communicates wirelessly with the radiation generator 11. The sensor panel has a detection surface 17 in which multiple pixels are arranged in a matrix and generate a signal charge in response to radiation R or visible light converted from radiation R by a scintillator. The electronic cassette 12 detects the radiation R that is irradiated from the radiation source 13 and passes through the patient P, and outputs a radiation image 18 of the patient P.

[0027] Since the electronic cassette 12 is portable and wireless, it can be used for so-called free radiography, as shown in Figure 1, by placing it on the supine radiography table (bed) 19 installed in the radiography room RM (under the patient P) and performing radiography. More specifically, Figure 1 shows the electronic cassette 12 being inserted between the supine radiography table 19 and the patient P to take an image of the patient P lying supine on the supine radiography table 19 (see also Figure 5). Also, as shown in Figure 2, the electronic cassette 12 can be used by housing it in the holder 21 of the standing radiography table 20 installed in the radiography room RM (see also Figure 6). The holder 21 can be raised and lowered vertically relative to the support column 22.

[0028] The main body 14 is rectangular in shape, and its center MC coincides with the center of the trolley 16. In other words, the main body 14 is erected in the center of the trolley 16. Also, the center of gravity CG of the radiation generator 11 (see Figure 3) is located in the main body 14. The main body 14 is divided into a front section 25 and a rear section 26. The front section 25 can move up and down relative to the rear section 26.

[0029] The base end of the arm 27 is attached to the front part 25. More specifically, the arm 27 is divided into a first part to which the base end is attached to the front part 25, and a second part to which the base end is attached to the first part. The radiation source 13 is attached to the tip of the second part, which is the free end opposite the base end.

[0030] The first part is vertically movable relative to the front part 25 and is also vertically foldable relative to the front part 25. The second part is vertically foldable relative to the first part. Furthermore, the second part is extendable and retractable. The radiation source 13 is rotatable, i.e., pivotable, relative to the second part. By displacing the arm 27 and the radiation source 13 relative to the arm 27, the height, horizontal position, and orientation (direction) of the radiation source 13 can be adjusted.

[0031] An operation panel 28 is provided on the upper surface of the rear section 26. The operation panel 28 is, for example, composed of a touch panel display and has the function of displaying information in addition to operation functions. The operation panel 28 is operated by an operator OP, such as a radiological technologist. The operator OP sets the irradiation conditions for radiation R through the operation panel 28. The operator OP also checks the radiation image 18 through the operation panel 28.

[0032] Furthermore, an irradiation switch (not shown) is provided at the rear 26. The irradiation switch is used by the operator OP to instruct the start of radiation irradiation. An extension cable is connected to the irradiation switch, and it can be detached from the rear 26 for use. The irradiation switch can only be operated after the travel control and positioning control, which will be described later, have been completed.

[0033] The radiation source 13 includes a radiation tube 30 and an irradiation field limiter 31. The radiation tube 30 generates radiation R. The radiation tube 30 is equipped with a filament, a target, a grid electrode, etc. (all not shown). A tube voltage is applied between the filament, which is the cathode, and the target, which is the anode, from a voltage generator (not shown) built into the rear section 26. The filament emits thermionic electrons toward the target in accordance with the applied tube voltage. The target emits radiation R in response to collisions with thermionic electrons emitted from the filament. The grid electrode is placed between the filament and the target and changes the flow rate of thermionic electrons from the filament toward the target in accordance with the voltage applied from the voltage generator. This flow rate of thermionic electrons from the filament toward the target is called the tube current. The tube voltage and tube current are set in the radiation source 13 as irradiation conditions, along with the irradiation time.

[0034] The irradiation field limiter 31, also called a collimator, limits the irradiation field of radiation R generated from the radiation tube 30. The irradiation field limiter 31 has a configuration in which, for example, four shielding plates made of lead or the like are placed on each side of a rectangle to shield the radiation R, and a rectangular exit aperture that transmits radiation is formed in the center. The irradiation field limiter 31 changes the size of the exit aperture by changing the position of each shielding plate, thereby changing the irradiation field of radiation R.

[0035] A camera 32 is attached to the radiation source 13. The camera 32 is used to assist in aligning the radiation source 13 with the electronic cassette 12. The camera 32 incorporates a visible light-sensitive image sensor, such as a CMOS (Complementary Metal Oxide Semiconductor) image sensor or a CCD (Charge-coupled Device) image sensor. The camera 32 captures moving images at a predetermined frame rate. The camera 32 is an example of a "camera" related to the technology of this disclosure.

[0036] There are a total of four wheels 15, located on the front, rear, left, and right sides of the bogie 16. In other words, the bogie 16 is a four-wheeled type. Each wheel 15 is a swivel type, for example, that rotates around a pivot axis that extends in the vertical direction (also called the vertical direction) perpendicular to the axis of rotation when the vehicle is moving. The main body 14 moves autonomously using this bogie 16. Note that the wheels 15 may also be non-holonomic wheels such as omni-wheels.

[0037] Here, autonomous driving refers to autonomously driving toward a set target location while recognizing the surrounding environment using environmental information sensors and estimating its own position. The target location is pre-set, for example, the position next to the supine imaging table 19 shown in Figure 1, and the position facing the standing imaging table 20 shown in Figure 2. In the radiation generating device 11, SLAM (Simultaneous Localization and Mapping) technology is used to achieve autonomous driving.

[0038] A camera 33 is provided on the trolley section 16. The camera 33 is used to support the autonomous movement of the main body section 14. The camera 33 photographs the area in front of the trolley section 16. Like the camera 32, the camera 33 incorporates a visible light-sensitive image sensor and captures moving images at a predetermined frame rate. The camera 33 is an example of an "environmental information sensor" related to the technology disclosed herein. The main body section 14, and by extension the radiation generator 11, can be driven not only autonomously but also manually by an operator OP.

[0039] As an example, as shown in Figure 3, the trolley section 16 incorporates a rotation mechanism 35 and a first locking mechanism 36. The rotation mechanism 35 and the first locking mechanism 36 are located below the center of gravity CG of the main body section 14. The rotation mechanism 35 includes a rotating disc 37, a rotating shaft 38, a motor 39, and a rotary encoder 40. The rotating shaft 38 is inserted and fixed through the center of the rotating disc 37. The motor 39 is connected to the rotating disc 37 via gears or the like. The rotating shaft 38 coincides with the vertical axis VA that passes through the center MC of the main body section 14. The rear part 26 of the main body section 14 is attached to the tip of the rotating shaft 38. Therefore, when the motor 39 is driven and the rotating disc 37 and the rotating shaft rotate, the main body section 14 rotates around the vertical axis VA relative to the trolley section 16. The rotary encoder 40 detects the rotation direction and amount of rotation of the rotating shaft 38, and by extension, the main body section 14.

[0040] The first locking mechanism 36 is an electromagnetic brake that acts on the rotating disc 37. Specifically, the first locking mechanism 36 is a spring-type electromagnetic brake and includes an electromagnetic coil, an armature, a brake lining, a brake disc, a spring, etc. In the first locking mechanism 36, a magnetic field is generated when the electromagnetic coil is energized, and the armature is pulled away from the brake disc. In this state, no frictional force is generated between the brake lining and the rotating disc 37, and the rotating disc 37 can rotate freely. On the other hand, in the first locking mechanism 36, when the power to the electromagnetic coil is cut off, the magnetic field of the electromagnetic coil disappears, and the armature is pressed against the brake disc by the biasing force of the spring. This generates a frictional force between the brake lining and the rotating disc 37, and the rotation of the rotating disc 37 is locked. This first locking mechanism 36 makes it possible to switch between a state in which the rotation of the main body 14 is allowed and a state in which the rotation of the main body 14 is locked. The first locking mechanism 36 may also be a pad brake. Furthermore, the first locking mechanism 36 may consist of a hole formed in the rotating disc 37 and a pin that can be inserted into and removed from the hole.

[0041] Figure 4 is a block diagram showing an example of the electrical configuration of the radiation generator 11. The processor 45 comprehensively controls the entire radiation generator 11. The processor 45 consists, for example, of a CPU (Central Processing Unit) and memory such as RAM (Random Access Memory), and functions as various processing units by loading and executing various programs into memory. Specifically, the processor 45 performs driving control, positioning control, and imaging control. Driving control is the control related to the autonomous driving of the main unit 14. Positioning control is the control related to the positioning of the radiation source 13 and the electronic cassette 12. Imaging control includes the control of radiation R irradiation by the radiation source 13 and the output control of the radiation image 18 by the electronic cassette 12.

[0042] The storage 46 consists of non-volatile memory such as a hard disk drive or solid-state drive. The storage 46 stores the operating program 47 and control data 48. The control data 48 includes data for driving control, data for position control, and data for image capture control. The data for driving control includes map data 73 (see Figure 8) created by SLAM technology. The data for position control includes a cassette contour extraction model 86 (see Figure 10) for extracting the contour OLC (see Figure 10) of the electronic cassette 12. The data for image capture control includes an irradiation condition table in which the irradiation conditions for each imaging area are registered.

[0043] The processor 45 is connected to the operation panel 28, the rotation mechanism 35, the first locking mechanism 36, the communication interface 50, the travel actuator 51, the alignment actuator 52, the radiation source position detection sensor 53, and the second locking mechanism 54. The processor 45 controls the display of various screens on the operation panel 28. The processor 45 also receives various operation instructions from the operator OP through the operation panel 28 and executes various controls according to the operation instructions. The communication interface 50 is, for example, a wireless communication interface and is responsible for wireless communication with the electronic cassette 12.

[0044] The processor 45 controls the driving of the rotating mechanism 35 and the first locking mechanism 36. Specifically, the processor 45 controls the rotation direction and amount of rotation of the motor 39 of the rotating mechanism 35. The processor 45 receives the detection results of the rotation direction and amount of rotation of the main body 14 from the rotary encoder 40 of the rotating mechanism 35. The processor 45 derives the position of the main body 14 based on the detection results. The processor 45 also controls the energization and disconnection of the electromagnetic coil of the first locking mechanism 36.

[0045] The travel actuator 51 includes a motor for rotating the wheels 15 under the control of the processor 45, and a motor for turning them. The alignment actuator 52 includes a motor for raising and lowering the front section 25, a motor for raising and lowering the arm 27, a motor for folding the second section of the arm 27, a motor for extending and retracting the second section, and a motor for rotating the radiation source 13 relative to the second section under the control of the processor 45.

[0046] The radiation source position detection sensor 53 measures the vertical direction and amount of vertical movement of the arm 27 relative to the front part 25, the bending direction and amount of bending of the second part of the arm 27 relative to the first part, the extension and retraction direction and amount of extension and retraction of the second part, and the rotation direction and amount of rotation of the radiation source 13 relative to the second part. The radiation source position detection sensor 53 is, for example, a rotary encoder, a potentiometer, or a gyro sensor, or a combination of several of these sensors. The radiation source position detection sensor 53 outputs the measured values ​​to the processor 45. The processor 45 derives the position and orientation of the radiation source 13 based on the measured values ​​of the radiation source position detection sensor 53.

[0047] The second locking mechanism 54 is a pad brake that acts on the left and right rear wheels of the four wheels 15. In the second locking mechanism 54, an actuator is driven to press the pad against the outer surface of the wheel 15, thereby generating braking force. The processor 45 controls the drive of the actuator to lock and unlock the rotation of the wheel 15 by the second locking mechanism 54. Note that the second locking mechanism 54 is not limited to a pad brake, but may also be an electromagnetic brake like the first locking mechanism 36.

[0048] As an example, as shown in Figures 5 and 6, a standby position HP for the radiation generator 11 is provided in a corner of the imaging room RM. At the standby position HP, battery charging, reception of imaging orders from the Radiology Information System (RIS), and setting of irradiation conditions are performed. The standby position HP occupies an area that is the same size as the radiation generator 11, or slightly larger.

[0049] In the imaging room RM, a first target position TP1 (see Figure 5) for the radiation generator 11 during supine imaging and a second target position TP2 (see Figure 6) for the radiation generator 11 during upright imaging are set. The first target position TP1 is located beside the supine imaging table 19, more specifically, directly opposite one of the longer sides of the supine imaging table 19. The second target position TP2 is directly opposite the upright imaging table 20, separated from the upright imaging table 20 by the SID distance required for upright imaging. The first target position TP1 and the second target position TP2 occupy the same area as the radiation generator 11, or slightly larger, than the radiation generator 11, similar to the standby position HP. In the following, the first target position TP1 and the second target position TP2 may be collectively referred to as target position TP.

[0050] During supine imaging, the radiation generator 11 travels from the standby position HP towards the first target position TP1 and stops when its own position PS (see Figure 8) reaches the first target position TP1 (see Figure 5). During upright imaging, the radiation generator 11 travels from the standby position HP towards the second target position TP2 and stops when its own position PS reaches the second target position TP2 (see Figure 6). Although not shown in the illustration, the radiation generator 11 may travel from the first target position TP1 towards the second target position TP2 in order to perform upright imaging after supine imaging. Also, the radiation generator 11 may travel from the second target position TP2 towards the first target position TP1 in order to perform supine imaging after upright imaging. Alternatively, it may be determined that the self-position PS has reached the target position TP when the self-position PS coincides with the center of the target position TP, or it may be determined that the self-position PS has reached the target position TP when the self-position PS falls within a range that includes the center of the target position TP with a certain margin.

[0051] Autonomous driving to the target position TP is initiated, for example, by an instruction from an operator OP via the control panel 28. Alternatively, the system may be configured to allow the start of autonomous driving to be initiated via a remote controller, in addition to or instead of the control panel 28.

[0052] The processor 45 performs driving control using SLAM technology. Specifically, as shown in Figures 7 and 8, the processor 45 functions as an image acquisition unit 60, a feature point extraction unit 61, a self-position estimation / map data creation unit 62, and a driving control unit 63.

[0053] The image acquisition unit 60 sequentially acquires images 70 of the surrounding environment of the radiation generator 11 (hereinafter referred to as "driving control images") captured by the camera 33 at a predetermined frame rate. After performing preprocessing such as noise reduction and distortion correction on the driving control images 70, the image acquisition unit 60 outputs the driving control images 70 to the feature point extraction unit 61. The driving control images 70 are an example of "output data" related to the technology of this disclosure.

[0054] The feature point extraction unit 61 uses algorithms such as ORB (Oriented FAST (Features from Accelerated Segment Test) and Rotated BRIEF (Binary Robust Independent Elementary Features)) or SURF (Speeded-Up Robust Features) to extract corners and other features of structures in the surrounding environment captured in the driving control image 70 as feature points FP. The feature point extraction unit 61 outputs the feature point extraction results 71 to the self-position estimation / map data creation unit 62. Although not shown in the diagram, the feature point extraction unit 61 also stores the feature point extraction results 71 in the storage 46. The feature point extraction results 71 are pairs of the coordinates of each feature point FP and their feature vectors.

[0055] The self-position estimation and map data creation unit 62 estimates the self-position PS of the radiation generator 11 while creating map data 73 of the surrounding environment. The self-position estimation and map data creation unit 62 receives the feature point extraction results 71 from the feature point extraction unit 61. In addition, the self-position estimation and map data creation unit 62 receives feature point extraction results 71P from multiple past frames (hereinafter referred to as feature point extraction results (past)) and map data 73P from multiple past frames (hereinafter referred to as map data (past)).

[0056] The feature point extraction results (past data) 71P and map data (past data) 73P are stored in storage 46 as data for driving control of control data 48. The feature point extraction results 71 and map data 73 that make up the feature point extraction results (past data) 71P and map data (past data) 73P consist of, for example, tens to hundreds of frames. The feature point extraction results (past data) 71P and map data (past data) 73P include feature point extraction results 71 and map data 73 that are considered to play an important role in estimating the self-position PS and creating the map data 73. Such feature point extraction results 71 and map data 73 are, for example, feature point extraction results 71 and map data 73 obtained every certain distance traveled. Also, for example, feature point extraction results 71 and map data 73 obtained when there has been a large change in viewpoint from the previous frame. Furthermore, for example, feature point extraction results 71 and map data 73 obtained when more than a set amount of new feature points FP have been extracted.

[0057] The self-localization and map data creation unit 62 compares the feature points FP from the feature point extraction result 71 from the feature point extraction unit 61 with the feature points FP from the feature point extraction result (past data) 71P. In this process, the self-localization and map data creation unit 62 refers to the feature vector of each feature point FP. More specifically, it recognizes feature points FP from the feature point extraction result 71 from the feature point extraction unit 61 and feature points FP from the feature point extraction result (past data) 71P where the distance (Euclidean distance, etc.) of the feature vectors is less than a threshold as the same feature point FP. Based on this comparison result of feature points FP and the map data (past data) 73P, the self-localization and map data creation unit 62 estimates the self-localization PS. Furthermore, the self-position estimation and map data creation unit 62 creates new map data 73 (updates map data 73) based on the feature point extraction results 71 from the feature point extraction unit 61, the feature point extraction results (past) 71P, the map data (past) 73P, and the estimation results 72. In this way, the self-position estimation and map data creation unit 62 performs the estimation of the self-position PS and the creation of map data 73 in parallel during the process of the radiation generator 11 autonomously moving. Note that the self-position estimation and map data creation unit 62 does not estimate the self-position PS until a sufficient amount of feature point extraction results (past) 71P has been accumulated, and only creates (updates) the map data 73.

[0058] The self-position estimation and map data creation unit 62 outputs the self-position estimation result 72 of the self-position PS to the driving control unit 63. The driving control unit 63 controls the driving of the driving actuator 51 to set the self-position PS as the target position TP. Although not shown in the diagram, the self-position estimation and map data creation unit 62 also stores the map data 73 in the storage 46. Specifically, the map data 73 is 3D data of the imaging room RM, including structures such as the supine imaging table 19 and the standing imaging table 20. The standby position HP and the target position TP are also registered in the map data 73.

[0059] Under the control of the driving control unit 63, the driving actuator 51 is driven, and when the self-position PS of the radiation generator 11 becomes the target position TP, the processor 45 transitions from driving control to alignment control, as shown in Figure 9 as an example. While driving control is being performed, the processor 45 locks the rotation of the main body 14 with the first locking mechanism 36 and releases the lock on the rotation of the wheels 15 with the second locking mechanism 54. Conversely, when the self-position PS of the radiation generator 11 becomes the target position TP and the system transitions from driving control to alignment control, the processor 45 releases the lock on the rotation of the main body 14 with the first locking mechanism 36 and locks the rotation of the wheels 15 with the second locking mechanism 54. The case where the self-position PS of the radiation generator 11 becomes the target position TP is an example of when the "setting conditions are met" in the technology of this disclosure.

[0060] As an example, as shown in Figure 10, the processor 45 functions as a cassette contour extraction unit 80, a source position and orientation derivation unit 81, and an alignment control unit 82.

[0061] The cassette contour extraction unit 80 receives sequential images 85 (hereinafter referred to as "position control images") including the patient P and the electronic cassette 12, captured by the camera 32 at a predetermined frame rate. When the self-position PS of the radiation generator 11 is set to the target position TP, the position control image 85 shows the patient P and the electronic cassette 12. In Figure 11, supine imaging is shown as an example, so the supine imaging table 19 is also shown in the position control image 85. The position control image 85 is an example of a "camera image" related to the technology of this disclosure. It is assumed that the positioning of the patient P and the electronic cassette 12 has been completed by the operator OP before the travel control and position control.

[0062] The cassette contour extraction unit 80 extracts the contour OLC of the electronic cassette 12 from the alignment control image 85 using the cassette contour extraction model 86. The contour OLC reveals the center CC (see Figure 12) of the detection surface 17 of the electronic cassette 12, and the orientation of the electronic cassette 12 relative to the radiation source 13. The cassette contour extraction unit 80 outputs the cassette contour extraction result 87 to the alignment control unit 82. Here, the contour OLC is exemplified as a contour that follows all sides of the electronic cassette 12, but it is not limited to this. The four corners of the electronic cassette 12 may also be extracted as contours.

[0063] The cassette contour extraction model 86 is a pre-trained model, for example, composed of a convolutional neural network, which is trained to output a cassette contour extraction result 87 when an alignment control image 85 is input. The cassette contour extraction model 86 is stored in the storage 46 as alignment control data for the control data 48.

[0064] As an example, as shown in Figure 11, in the learning phase, the cassette contour extraction model 86 is given training data 90. The training data 90 consists of a training alignment control image 85L and ground truth data 87CA. The training alignment control image 85L shows an electronic cassette 12. The ground truth data 87CA is data annotated with the contour OLC of the electronic cassette 12 shown in the training alignment control image 85L, and is, so to speak, data for checking the answer.

[0065] The cassette contour extraction model 86 receives a training alignment control image 85L as input. The cassette contour extraction model 86 outputs a training cassette contour extraction result 87L in response to the input of the training alignment control image 85L. Based on this training cassette contour extraction result 87L and the ground truth data 87CA, a loss calculation is performed on the cassette contour extraction model 86 using a loss function. Then, based on the result of the loss calculation, various coefficients of the cassette contour extraction model 86 (such as the coefficients of the convolutional layer filters) are updated, and the cassette contour extraction model 86 is updated according to the update settings.

[0066] In the learning phase of the cassette contour extraction model 86, the above series of processes—inputting the learning alignment control image 85L into the cassette contour extraction model 86, outputting the learning cassette contour extraction result 87L from the cassette contour extraction model 86, loss calculation, update settings, and updating the cassette contour extraction model 86—are repeated while the learning data 90 is exchanged. The repetition of the above series of processes ends when the extraction accuracy of the learning cassette contour extraction result 87L reaches a predetermined set level. The cassette contour extraction model 86, whose extraction accuracy has reached the set level, is stored in the storage 46 and used by the cassette contour extraction unit 80. Alternatively, learning may be terminated after the above series of processes has been repeated a set number of times, regardless of the extraction accuracy of the learning cassette contour extraction result 87L.

[0067] The radiation source position and orientation derivation unit 81 derives the position and orientation of the radiation source 13 based on the measurement values ​​of the radiation source position detection sensor 53. The radiation source position and orientation derivation unit 81 outputs the derivation result 88 to the alignment control unit 82. The derivation result 88 consists of the coordinates in the alignment control image 85 of the irradiation center RC of radiation R (see Figure 12) and the coordinates in the alignment control image 85 of the rectangular frame F (see Figure 12) that indicates the orientation of the radiation source 13. Since the positional relationship between the radiation source 13 and the camera 32 is known, the coordinates in the alignment control image 85 of the irradiation center RC and frame F can be easily calculated from the measurement values ​​of the radiation source position detection sensor 53.

[0068] The alignment control unit 82 controls the driving of the rotation mechanism 35 and the alignment actuator 52 in order to align the radiation source 13 and the electronic cassette 12 directly. More specifically, as shown in Figure 12 as an example, if the orientation of the radiation source 13 is tilted relative to the electronic cassette 12, the alignment control unit 82 drives the rotation mechanism 35 to rotate the main body 14 to eliminate the tilt, thereby rotating the radiation source 13. Specifically, if the tilt angle of the radiation source 13 relative to the electronic cassette 12 is θ, the alignment control unit 82 rotates the radiation source 13 to make the tilt angle θ zero. The tilt angle θ is the angle between the radiation source 13 and the electronic cassette 12 around the normal to the detection surface 17. More precisely, the tilt angle θ is the angle between the sides extending left and right of the radiation source 13 and the long side of the detection surface 17 around the normal to the detection surface 17.

[0069] Furthermore, if the irradiation center RC of radiation R and the center CC of the detection surface 17 of the electronic cassette 12 are misaligned, the alignment control unit 82 moves the radiation source 13 to correct the misalignment. Note that the tilt may be corrected after correcting the misalignment between the irradiation center RC of radiation R and the center CC of the detection surface 17 of the electronic cassette 12. Also, although Figure 12 illustrates the case where the orientation of the radiation source 13 is tilted around the normal to the detection surface 17, it is not limited to this. Even if the orientation of the radiation source 13 is tilted around an axis along the long side or short side of the detection surface 17, the alignment control unit 82 rotates the radiation source 13 to correct the tilt.

[0070] Next, the operation of the above configuration will be explained with reference to the flowchart shown in Figure 13 as an example. Before imaging, the radiation generator 11 is waiting at the standby position HP in the imaging room RM. At this time, under the control of the processor 45, the rotation of the main body 14 is locked by the first locking mechanism 36, and the rotation of the wheels 15 is locked by the second locking mechanism 54.

[0071] A shooting order is transmitted from the radiation information system to the radiation generator 11. The operator OP operates the control panel 28 to set the irradiation conditions according to the shooting order (step ST100).

[0072] The operator OP places the electronic cassette 12 on the supine imaging table 19 if performing supine imaging, or places the electronic cassette 12 in the holder 21 of the standing imaging table 20 if performing standing imaging. Then, the operator OP aligns the patient P with the electronic cassette 12 (step ST110). Specifically, the center IC of the imaging area of ​​the patient P (see Figure 17) is aligned with the center CC of the detection surface 17 of the electronic cassette 12. In addition, the body axis (head-to-tail axis) of the patient P is made parallel to the long side of the detection surface 17 of the electronic cassette 12.

[0073] In response to instructions from the operator OP, under the control of the processor 45, the lock on the rotation of the wheels 15 by the second locking mechanism 54 is released (step ST120), and the autonomous movement of the radiation generator 11 from the standby position HP to the target position TP begins (step ST130). During autonomous movement, the processor 45 performs driving control using SLAM technology, as shown in Figures 7 and 8 as an example.

[0074] Specifically, first, the driving control image 70 captured by the camera 33 is acquired by the image acquisition unit 60. The driving control image 70 is output from the image acquisition unit 60 to the feature point extraction unit 61. The feature point extraction unit 61 then extracts feature points FP of structures present in the surrounding environment captured in the driving control image 70. The feature point extraction result 71 is output from the feature point extraction unit 61 to the self-position estimation / map data creation unit 62. The feature point extraction result 71 is also stored in the storage 46.

[0075] In the self-position estimation / map data creation unit 62, the self-position PS of the radiation generator 11 is estimated based on the feature point extraction results 71, the feature point extraction results (past) 71P, and the map data (past) 73P, and the estimation result 72 is output. In addition, the self-position estimation / map data creation unit 62 creates map data 73 based on the feature point extraction results 71, the feature point extraction results (past) 71P, the map data (past) 73P, and the estimation result 72. The estimation result 72 of the self-position PS is output from the self-position estimation / map data creation unit 62 to the driving control unit 63. The map data 73 is stored in the storage 46.

[0076] Under the control of the travel control unit 63, the drive of the travel actuator 51 is controlled to set the self-position PS to the target position TP. In this way, travel control is performed. Travel control continues until the self-position PS of the radiation generator 11 reaches the target position TP (NO in step ST140).

[0077] When the radiation generator 11's own position PS becomes the target position TP (YES in step ST140), as shown in Figure 9, the lock on the rotation of the main body 14 by the first locking mechanism 36 is released, and the rotation of the wheels 15 is locked by the second locking mechanism 54 (step ST150). Then, the system transitions from travel control to positioning control (step ST160).

[0078] As shown in Figure 10, the alignment control image 85 captured by the camera 32 is input to the cassette contour extraction unit 80. The cassette contour extraction unit 80 uses the cassette contour extraction model 86 to extract the OLC contour of the electronic cassette 12 from the alignment control image 85. The cassette contour extraction result 87 is output from the cassette contour extraction unit 80 to the alignment control unit 82.

[0079] The radiation source position and orientation derivation unit 81 derives the position and orientation of the radiation source 13 based on the measurement values ​​of the radiation source position detection sensor 53. The derivation results 88 of the position and orientation of the radiation source 13 are output from the radiation source position and orientation derivation unit 81 to the alignment control unit 82.

[0080] Under the control of the alignment control unit 82, the rotation mechanism 35 and the alignment actuator 52 are controlled to align the radiation source 13 and the electronic cassette 12. Alignment control is performed in this manner. Alignment control continues until the radiation source 13 and the electronic cassette 12 are aligned (NO in step ST170).

[0081] When the radiation source 13 and the electronic cassette 12 are facing each other directly (YES in step ST170), the irradiation switch can be operated. The operator OP operates the irradiation switch to instruct the start of radiation irradiation. As a result, radiation R is irradiated from the radiation source 13, and the radiation image 18 is output from the electronic cassette 12 (step ST180).

[0082] As described above, the radiation generator 11 has a configuration in which a main body 14, to which an arm 27 that holds a radiation source 13 that emits radiation R toward the patient P is attached, is mounted on a trolley 16 having wheels 15. The radiation generator 11 is equipped with a rotation mechanism 35 that allows the main body 14 to rotate around a vertical axis VA relative to the trolley 16.

[0083] The radiation source 13 is located above the center of gravity CG of the main body 14. The radiation source 13 is projected toward the patient P. Therefore, if the arm 27 is rotated as in the conventional method, the main body 14 may move due to the reaction force, or the arm 27 may not stop in the intended position due to inertia. However, in the technology of this disclosure, the rotation mechanism 35 allows the main body 14 to rotate around the vertical axis VA relative to the trolley 16. Therefore, there is no risk of the main body 14 moving due to the reaction force, or the arm 27 not stopping in the intended position due to inertia, and the rotation of the radiation source 13 can be stabilized. Consequently, it is possible to contribute to high-precision alignment between the radiation source 13 and the electronic cassette 12.

[0084] As shown in Figure 3, the radiation generator 11 is equipped with a first locking mechanism 36 that can lock the rotation of the main body 14. This prevents unintentional rotation of the main body 14, allowing it to be rotated only when necessary. This prevents situations such as the main body 14 rotating unintentionally and the radiation source 13 hitting the operator OP, thereby enhancing safety.

[0085] As shown in Figure 9, when the self-position PS becomes the target position TP, the lock by the first locking mechanism 36 is released. This allows the main body 14 to rotate at the right time, enabling smooth alignment control.

[0086] As shown in Figures 7 and 8, the driving control system estimates the vehicle's own position PS from the driving control images 70 captured by the camera 33, while simultaneously creating map data 73 of the surrounding environment. This allows for highly accurate estimation of the vehicle's own position PS, enabling autonomous driving even in unfamiliar environments. Furthermore, the vehicle can reach its target position TP via an appropriate driving path, such as the shortest path or a path that avoids obstacles.

[0087] The driving control unit 63 performs autonomous driving based on the map data 73. This enables advanced autonomous driving and reduces the workload for the operator OP.

[0088] As shown in Figure 4, the bogie section 16 has a second locking mechanism 54 that can lock the rotation of the wheels 15. This prevents the wheels 15 from rotating unintentionally, and allows them to rotate only when necessary.

[0089] As shown in Figure 9, when the lock by the first locking mechanism 36 is released, the lock by the second locking mechanism 54 is activated. This reduces the risk of the trolley section 16 moving due to the reaction force of the rotation of the main body section 14 by the rotating mechanism 35. This allows for more stable rotation of the radiation source 13.

[0090] As shown in Figure 3, the first locking mechanism 36 is an electromagnetic brake. Therefore, the rotation of the main body 14 can be locked with a relatively inexpensive and simple configuration.

[0091] As shown in Figure 12, the alignment control unit 82 controls the rotation of the main body 14 by the rotation mechanism 35 based on the tilt angle θ between the radiation source 13 and the electronic cassette 12. This reduces the workload for the operator OP.

[0092] As shown in Figure 3, the rotating mechanism 35 rotates around the vertical axis VA that passes through the center MC of the main body 14. This allows for more stable rotation of the main body 14, and consequently, the radiation source 13.

[0093] [Second Embodiment] In the first embodiment described above, when the self-position PS becomes the target position TP, the lock on the rotation of the main body 14 by the first locking mechanism 36 is released, and the rotation of the wheels 15 is locked by the second locking mechanism 54. However, the embodiment is not limited to this. For example, it may be as shown in Figures 14 and 15.

[0094] As shown in Figure 14, the processor 45 of this embodiment functions as a cassette detection unit 95 in addition to the processing units of the first embodiment described above. The cassette detection unit 95 receives an alignment control image 85 as input. The cassette detection unit 95 uses image recognition technology to detect whether or not an electronic cassette 12 is visible in the alignment control image 85.

[0095] In this embodiment, when the cassette detection unit 95 detects that the electronic cassette 12 is visible in the alignment control image 85, the processor 45 releases the lock on the rotation of the main body 14 by the first locking mechanism 36 and locks the rotation of the wheels 15 by the second locking mechanism 54, thereby transitioning from driving control to alignment control. The detection of the electronic cassette 12 being visible in the alignment control image 85 is an example of "when the setting conditions are met" in the technology of this disclosure. The cassette detection unit 95 may also use a trained model, such as the cassette contour extraction model 86 of the first embodiment, to detect whether or not the electronic cassette 12 is visible in the alignment control image 85.

[0096] Alternatively, as shown in Figure 15, the processor 45 of this embodiment functions as a patient detection unit 100 in addition to the processing units of the first embodiment described above. The patient detection unit 100 receives an image 85 for alignment control. The patient detection unit 100 uses image recognition technology to detect whether or not patient P is visible in the image 85 for alignment control. When the patient detection unit 100 detects that patient P is visible in the image 85 for alignment control, the processor 45 of this embodiment releases the lock on the rotation of the main body 14 by the first locking mechanism 36 and locks the rotation of the wheels 15 by the second locking mechanism 54, thereby transitioning from driving control to alignment control. The detection of patient P being visible in the image 85 for alignment control is an example of "when the setting conditions are met" according to the technology of this disclosure. In this way, when the position control image 85 detects that the electronic cassette 12 or patient P is visible, the lock on the rotation of the main body 14 by the first locking mechanism 36 is released, and the rotation of the wheels 15 is locked by the second locking mechanism 54. This allows the main body 14 to rotate at the right time and the rotation of the wheels 15 to be locked, enabling smooth position control.

[0097] [Third Embodiment] As an example, as shown in Figure 16, in this embodiment, when the self-position PS becomes the target position TP, the processor 45 displays a rotation lock release button 102 on the operation panel 28. When the rotation lock release button 102 is selected by the operator OP and a lock release instruction is input, the processor 45 releases the lock on the rotation of the main body 14 by the first lock mechanism 36 and locks the rotation of the wheels 15 by the second lock mechanism 54. When a lock release instruction is input, this is an example of "when the setting conditions are met" in the technology of this disclosure. The lock release instruction is also an example of "an operation instruction to release the lock" in the technology of this disclosure. With this configuration, the main body 14 can be rotated in a timely manner and the rotation of the wheels 15 can be locked, and positioning control can be executed smoothly. The rotation lock release button 102 may be provided as a physical button on the radiation source 13 or the main body 14, etc.

[0098] [Fourth Embodiment] In the first embodiment described above, the contour OLC of the electronic cassette 12 is extracted from the alignment control image 85, but this is not limited to this. For example, it may be as shown in Figure 17.

[0099] In Figure 17, the processor 45 of this embodiment functions as an articular point extraction unit 105 instead of the cassette contour extraction unit 80 of the first embodiment. The articular point extraction unit 105 receives sequential input of alignment control images 85. The articular point extraction unit 105 extracts the articular points J of patient P from the alignment control images 85 using the articular point extraction model 106. Figure 17 illustrates the case where both shoulder joints, both elbow joints, and both hip joints are extracted as articular points J. The lines connecting each articular point J indicate the center IC of the imaging area of ​​patient P and the posture of patient P relative to the radiation source 13. The articular point extraction model 106 is a trained model composed of, for example, a convolutional neural network, similar to the cassette contour extraction model 86. The articular point extraction unit 105 outputs the articular point extraction result 107 to the alignment control unit 82.

[0100] If the orientation of the radiation source 13 is tilted relative to the patient P, the alignment control unit 82 drives the rotation mechanism 35 to rotate the main body 14 to correct the tilt, thereby rotating the radiation source 13. In this case, the tilt angle θ is, as an example shown in Figure 18, the angle made between the sides of the radiation source 13 extending to the left and right, the line connecting both shoulder joints, and the perpendicular line passing through the center IC of the imaging area of ​​the patient P, i.e., the body axis (head-to-tail axis) of the patient P. Furthermore, if the irradiation center RC of the radiation R and the center IC of the imaging area of ​​the patient P are misaligned, the alignment control unit 82 controls the drive of the alignment actuator 52 to move the radiation source 13 to correct the misalignment. By extracting the joint points J of the patient P from the alignment control image 85 in this way, it is possible to contribute to more accurate alignment of the radiation source 13 and the electronic cassette 12. In this case, if the long side of the supine imaging table 19 is not parallel to the head-to-tail axis of the patient P, and the irradiation center RC of the radiation R is misaligned with the center IC of the imaging area of ​​the patient P, the misalignment may be corrected by moving the radiation generator 11 along the head-to-tail axis of the patient P (moving the radiation generator 11 diagonally with respect to the long side of the supine imaging table 19).

[0101] [Fifth Embodiment] As an example, as shown in Figures 19 and 20, a geomagnetic sensor 110 may be provided on the radiation source 13, and the tilt angle θ may be detected based on the output from the geomagnetic sensor 110.

[0102] In Figure 20, the processor 45 of this embodiment functions as a tilt angle detection unit 115 in addition to the processing units of the first embodiment described above. The tilt angle detection unit 115 receives the azimuth angle detection result 116 of the radiation source 13 from the geomagnetic sensor 110 and the supine imaging table azimuth angle data 117 as input. The azimuth angle detection result 116 includes the angle ΨX shown in Figure 19. Angle ΨX is the angle between the left and right sides of the radiation source 13 and the vertical axis VA with respect to magnetic north. The supine imaging table azimuth angle data 117 includes the angle ΨY shown in Figure 19. Angle ΨY is the angle between the long side of the supine imaging table 19 and the vertical axis VA with respect to magnetic north. The supine imaging table azimuth angle data 117 is pre-registered in the storage 46 by the hospital administrator or the like as data for positional control of the control data 48. The angle ΨX in the azimuth detection result 116 is an example of the "azimuth angle of the main body" related to the technology of this disclosure. The angle ΨY in the supine imaging table azimuth data 117 is an example of the "azimuth angle of the imaging table" related to the technology of this disclosure.

[0103] The tilt angle detection unit 115 calculates the difference (ΨX-ΨY) between the angle ΨX of the azimuth angle detection result 116 and the angle ΨY of the supine imaging table azimuth angle data 117. The tilt angle detection unit 115 outputs the calculated difference as the tilt angle θ to the alignment control unit 82.

[0104] Thus, in the fifth embodiment, the tilt angle detection unit 115 derives the tilt angle θ as the difference between the azimuth angle ΨX of the radiation source 13 detected by the geomagnetic sensor 110 and the azimuth angle ΨY of the supine imaging table 19. Therefore, compared to the first and fourth embodiments, which detect the tilt angle θ based on the alignment control image 85, the tilt angle θ can be detected more easily.

[0105] Alternatively, the tilt angle θ may be derived based on the output of a sensor such as a rotary encoder that detects the rotation direction and amount of rotation of the wheel 15. In this case, the tilt angle θ is derived by determining the path traveled from the standby position HP to the long side of the supine imaging table 19 and its current orientation from the output of the sensor such as a rotary encoder, using the angle with the long side of the supine imaging table 19 at the standby position HP as a reference. Alternatively, a marker may be attached to the long side of the supine imaging table 19, and the marker may be photographed with a camera installed on the main unit 14. The tilt angle θ may then be derived from the degree of distortion of the marker pattern in the captured image. Furthermore, a distance sensor such as a TOF (Time-of-Flight) sensor may be installed on the main unit 14. The distances DP1 and DP2 to two preset points P1 and P2 on the long side of the supine imaging table 19 may be determined from the distance image output by the distance sensor, and the tilt angle θ may be derived based on the difference between the distances DP1 and DP2 (DP1-DP2).

[0106] [Sixth Embodiment] As an example, as shown in Figure 21, in this embodiment, a first magnet 120 is attached to the main body 14 and a second magnet 121 is attached to the supine imaging table 19. The first magnet 120 is positioned at the center of the front front portion 25 of the main body 14, at a height that coincides with the long side of the supine imaging table 19. The second magnet 121 is positioned on the long side of the supine imaging table 19, facing the first magnet 120 when the radiation generator 11 is at the first target position TP1 and the tilt angle θ is 0°. The first magnet 120 is an electromagnet, and a magnetic field is generated when power is applied, and the magnetic field disappears when the power is cut off. The processor 45 cuts off power to the first magnet 120 until the radiation generator 11 reaches the first target position TP1, and then starts powering the first magnet 120 once the radiation generator 11 reaches the first target position TP1.

[0107] When the radiation generator 11 reaches the first target position TP1 and the lock on the rotation of the main body 14 by the first locking mechanism 36 is released, the first magnet 120 is attracted to the second magnet 121, thereby aligning the radiation source 13 with the supine imaging table 19. This eliminates the need to detect the tilt angle θ or drive the rotation mechanism 35 to correct the tilt.

[0108] [Seventh Embodiment] In the first embodiment described above, the main body 14 is rotated around a vertical axis VA that passes through the center MC of the main body 14, but this is not the only way. For example, as shown in the radiation generator 123 in Figure 22, the main body 14 may be rotated around a vertical axis VA that passes through the focal point RFP of the radiation R. In this case, the rotation mechanism rotates the main body 14 along an arc-shaped guide rail 124 erected on the trolley 16, with the focal point RFP as the center. In this way, the position of the focal point RFP does not change even when the main body 14 is rotated, so the positioning of the radiation source 13 and the electronic cassette 12 can be easily completed. Alternatively, the main body 14 may be rotated around a vertical axis VA that passes through both the center MC of the main body 14 and the focal point RFP of the radiation R.

[0109] [Eighth Embodiment] In the embodiments described above, a radiation generator 11 equipped with a rotating mechanism 35 has been described, but the invention is not limited to this. As an example, as shown in Figure 23, the rotating mechanism 35 may be applied to a mobile imaging table 125. The imaging table 125 has a configuration in which a main body 127 to which an arm 126 for holding an electronic cassette 12 at its tip is attached is mounted on a trolley 129 having wheels 128, and the rotating mechanism 35 is built into the trolley 129.

[0110] The electronic cassette 12, like the radiation source 13, is relatively heavy, weighing several kilograms. Therefore, with this configuration, there is no risk of the main body 127 moving due to reaction force when the arm 126 is rotated, or of the arm 126 failing to stop in the intended position due to inertia, thus stabilizing the rotation of the electronic cassette 12. Consequently, it becomes possible to contribute to high-precision positioning between the patient P and the electronic cassette 12, as well as between the radiation source 13 and the electronic cassette 12.

[0111] In the embodiments described above, a supine imaging table 19 is used as an example, but the invention is not limited to this. The main body 14 may be rotated to eliminate any tilt relative to the standing imaging table 20.

[0112] Although an example of autonomous movement of the radiation generator 11 has been described, the invention is not limited to this. An operator OP may manually move the radiation generator 11. Similarly, although an example of automatically rotating the main body 14 by controlling the drive of the rotation mechanism 35 has been described, the invention is not limited to this. An operator OP may manually rotate the main body 14.

[0113] A guide rail may be provided on the long side of the supine imaging table 19, and a projection that connects to the guide rail may be provided on the main body 14, allowing the radiation generator 11 to be moved along the guide rail.

[0114] Not only the main unit 14, but also the top plate of the supine imaging table 19 may be configured to be rotatable. The top plate may be rotated to eliminate any tilting.

[0115] The alignment control image 85 may be displayed on the operation panel 28. In this case, the contour OLC of the electronic cassette 12, the center CC of the detection surface 17 of the electronic cassette 12, the irradiation center RC of the radiation R, etc., may be superimposed on the alignment control image 85 as markers.

[0116] Camera 32 may be attached to the arm 27 instead of the radiation source 13. Similarly, camera 33 may be provided on the main body 14 instead of the trolley 16. There may be multiple cameras 32 and 33.

[0117] Cameras 32 and 33 may be combined into a single camera. In this case, the camera orientation is set so that it can capture the driving control image 70 when driving control is being performed, and so that it can capture the alignment control image 85 when alignment control is being performed.

[0118] The environmental information sensor is not limited to the example camera 33. LiDAR (Light Detection and Ranging) sensors, TOF sensors, etc., may also be used. In addition, an IMU (Inertial Measurement Unit) combining an accelerometer and a gyroscope, an ultrasonic sensor, a radar sensor, a magnetic sensor, etc., may also be used.

[0119] The radiation image detection device is not limited to the example electronic cassette 12. A CR (Computed Radiography) cassette may also be used. Furthermore, the subject is not limited to the example patient P. A diseased animal such as a dog or cat may also be used.

[0120] In each of the above embodiments, the processing of each processing unit, such as the image acquisition unit 60, feature point extraction unit 61, self-position estimation / map data creation unit 62, driving control unit 63, cassette contour extraction unit 80, source position / attitude derivation unit 81, alignment control unit 82, cassette detection unit 95, patient detection unit 100, joint point extraction unit 105, and tilt angle detection unit 115, is executed on any computer. Furthermore, any computer may execute these processes using a processor as hardware, a program as software, or a combination thereof. In that case, the processor is configured to work in cooperation with the program to execute the various processes in each of the above embodiments, and can function as each unit or means in each of the above embodiments. Also, the execution order of the processor's processes is not limited to the order described and may be changed as appropriate. Any computer may be a general-purpose computer, a computer designed for a specific application, a workstation, or any other system capable of executing each process.

[0121] A processor may consist of one or more hardware components, and the type of hardware is not limited. For example, a processor may consist of the example CPU, or programmable logic devices such as an MPU (Micro Processing Unit), FPGA (Field Programmable Gate Array), dedicated circuits for executing specific processes such as an ASIC (Application Specific Integrated Circuit), a GPU (Graphic Processing Unit), or an NPU (Neural Processing Unit). Furthermore, the type of hardware may be a combination of different types of hardware. When multiple hardware components are configured to execute one or more processes of a processor, these multiple hardware components may reside in physically separate devices or in the same device. Also, in any embodiment, the order of each process performed by the processor is not limited to the order described above and may be changed as appropriate. The hardware is composed of electrical circuits (circuitry) that combine circuit elements such as semiconductor elements.

[0122] Furthermore, the program may be firmware or software such as microcode. Alternatively, the program may be, for example, a set of program modules, each function of which may be implemented by a processor configured to perform its respective function. The program may be program code or multiple code segments stored on one or more non-temporary computer-readable media (e.g., storage media or other storage devices). The program may be divided and stored on multiple non-temporary computer-readable media located in physically separate devices. Program code or code segments may represent any combination of procedures, functions, subprograms, routines, subroutines, modules, software packages, classes, or instructions, data structures, or program statements. Program code or code segments may be connected to other code segments or hardware circuits by sending and receiving information, data, arguments, parameters, or memory contents.

[0123] From the above description, the technology described in the following supplementary information can be understood.

[0124] [Additional note 1] A radiation generating device in which a main body, to which an arm is attached that holds a radiation source that emits radiation toward a subject, is mounted on a trolley having wheels, A radiation generating device comprising a rotation mechanism that allows the main body to rotate around a vertical axis relative to the trolley. [Additional note 2] The radiation generating device according to Appendix 1, further comprising a first locking mechanism capable of locking the rotation of the main body by the aforementioned rotating mechanism. [Additional note 3] The radiation generating device described in Appendix 2, wherein the lock by the first locking mechanism is released when the setting conditions are met. [Additional note 4] The radiation generating device according to Appendix 3, wherein the lock by the first locking mechanism is released when its own position becomes the target position. [Additional note 5] Environmental information sensors and, Processor and Equipped with, The aforementioned processor, A radiation generating device according to Appendix 4, which estimates its own position from the output data of the environmental information sensor and creates map data of the surrounding environment. [Additional note 6] A radiation generating device as described in Appendix 5, which is capable of autonomous driving based on the aforementioned map data. [Additional note 7] Equipped with a camera, The radiation generating device according to Appendix 3, wherein the lock by the first locking mechanism is released when the radiation image detection device or the subject is detected to have been captured in the image of the camera. [Additional note 8] The radiation generating device according to Appendix 3, wherein the lock by the first locking mechanism is released when an operation instruction to release the lock is input. [Additional note 9] The radiation generating device according to any one of Appendix 2 to Appendix 8, wherein the trolley portion has a second locking mechanism capable of locking the rotation of the wheels. [Additional Note 10] The radiation generating device according to Appendix 9, wherein when the lock by the first locking mechanism is released, the lock by the second locking mechanism is performed. [Additional Note 11] The radiation generating device according to any one of the appendices 2 to 10, wherein the first locking mechanism is an electromagnetic brake. [Additional Note 12] Equipped with a processor, The aforementioned processor, A radiation generating device according to any one of the appendices 1 to 11, which controls the rotation of the main body by the rotation mechanism based on the inclination angle between the radiation source and the radiation image detection device, the imaging table, or the subject. [Additional Note 13] The aforementioned processor, The radiation generating device according to Appendix 12, wherein the difference between the azimuth angle of the radiation source detected by the geomagnetic sensor and the azimuth angle of the imaging table is derived as the tilt angle. [Additional Note 14] The main body is provided with a first magnet, A radiation generating device according to any one of the appendices 1 to 13, wherein the first magnet is attracted to a second magnet provided on the imaging table, thereby aligning the radiation source with the imaging table. [Additional Note 15] The radiation generating device according to any one of Appendix 1 to Appendix 14, wherein the rotating mechanism rotates around the vertical axis passing through at least one of the center of the main body and the focal point of the radiation.

[0125] Furthermore, the technology described in the following supplementary notes can be understood from the description of the eighth embodiment above.

[0126] [Additional Note 16] A radiography platform in which a main body to which an arm for holding a radiographic image detection device is attached is mounted on a trolley having wheels, The vehicle is equipped with a rotation mechanism that allows the main body to rotate around a vertical axis relative to the trolley. A shooting platform.

[0127] The technology of this disclosure can be appropriately combined with the various embodiments and / or variations described above. Furthermore, it is understood that various configurations can be adopted without departing from the spirit of the invention, and the invention is not limited to the embodiments described above. In addition, the technology of this disclosure extends not only to programs, but also to storage media for non-temporarily storing programs, and to computer program products containing programs.

[0128] The descriptions and illustrations presented above are detailed explanations of the technical aspects of this disclosure and are merely examples of the technical aspects. For example, the above descriptions of the structure, function, operation, and effect are examples of the structure, function, operation, and effect of the technical aspects of this disclosure. Therefore, it goes without saying that you may delete unnecessary parts, add new elements, or replace elements in the descriptions and illustrations presented above, as long as you do not deviate from the essence of the technical aspects of this disclosure. Furthermore, in order to avoid confusion and facilitate understanding of the technical aspects of this disclosure, explanations of common technical knowledge and the like that do not require special explanation to enable the implementation of the technical aspects of this disclosure have been omitted from the descriptions and illustrations presented above.

[0129] In this specification, "A and / or B" is synonymous with "at least one of A and B." That is, "A and / or B" means that it may be A alone, or B alone, or a combination of A and B. Furthermore, in this specification, the same concept as "A and / or B" applies when expressing three or more things linked by "and / or."

[0130] All documents, patent applications, and technical standards described herein are incorporated by reference to the same extent as if each individual document, patent application, and technical standard were specifically and individually noted to be incorporated by reference. [Explanation of symbols]

[0131] 10. Radiography System 11, 123 Radiation Generating Devices 12 Electronic Cassettes 13 Radiation source 14, 127 Main body 15, 128 wheels 16, 129 Bogie section 17 Detection surface 18. Radiological images 19 Recumbent photography stand 20 Standing position imaging table 21 Holder 22 Posts 25 Front 26 Rear 27, 126 arms 28 Control Panel 30 Radiation tubes 31 Irradiation field limiter 32, 33 Camera 35 Rotation mechanism 36. First locking mechanism 37. Rotating disk 38 Rotation axis 39 Motor 40 Rotary Encoders 45 processors 4 wireless storage 47 Operating Program 48 Control data 50 Communication I / F 51. Drive actuator 52 Alignment Actuator 53. Source position detection sensor 54 Second locking mechanism 60 Image acquisition unit 61 Feature Point Extraction Unit 62 Self-Position Estimation and Map Data Creation Section 63 Driving control unit 70 Images for driving control 71 Feature point extraction results 71P Feature point extraction results (past data) 72 Estimation results 73 Map data 73P Map data (past data) 80 Cassette contour extraction section 81 Source position / attitude derivation part 82 Alignment Control Unit 85 Image for alignment control 85L Image for learning and alignment control 86 Cassette Contour Extraction Model 87 Cassette contour extraction results 87CA Correct Answer Data 87L Training Cassette Contour Extraction Results 88 Derivation results 90 training data 95 Cassette detection unit 100 Patient detection unit 102 Rotation lock release button 105 Articular point extraction area 106 Joint Point Extraction Model 107 Joint point extraction results 110 Geomagnetic Sensor 115 Tilt angle detection unit 116. Azimuth detection results 117 Supine position imaging platform azimuth data 120 First Magnet 121 Second Magnet 124 Guide Rails 125 Shooting platform ΨX is the angle between the sides extending to the left and right of the radiation source and the vertical axis with respect to magnetic north. ΨY Angle between the long side of the supine imaging table and magnetic north around the vertical axis. θ - angle of inclination The center of the detection surface of the CC electronic cassette. CG Center of gravity of radiation generator DPI Frame F FP characteristic points HP standby position Center of the IC imaging area J joint point MC main unit center Outline of an OLC electronic cassette OP Operator P patient PS Self-position R radiation RC radiation irradiation center RFP (Request for Proposal) Radiation Focus RM Photo Studio ST100, ST110, ST120, ST130, ST140, ST150, ST160, ST170, ST180 Step TP target position TP1, TP2 1st target position, 2nd target position VA Vertical Axis

Claims

1. A radiation generating device in which a main body, to which an arm is attached that holds a radiation source that emits radiation toward a subject, is mounted on a trolley having wheels, A radiation generating device comprising a rotation mechanism that allows the main body to rotate around a vertical axis relative to the trolley.

2. The radiation generating device according to claim 1, further comprising a first locking mechanism capable of locking the rotation of the main body by the aforementioned rotating mechanism.

3. The radiation generating device according to claim 2, wherein the lock by the first locking mechanism is released when the setting conditions are met.

4. The radiation generating device according to claim 3, wherein the lock by the first locking mechanism is released when the device's own position becomes the target position.

5. Environmental information sensors and, Processor and Equipped with, The aforementioned processor, The radiation generating device according to claim 4, which estimates its own position from the output data of the environmental information sensor and creates map data of the surrounding environment.

6. The radiation generating device according to claim 5, which is capable of autonomous driving based on the aforementioned map data.

7. Equipped with a camera, The radiation generating device according to claim 3, wherein the lock by the first locking mechanism is released when the radiation image detection device or the subject is detected to have been captured in the image of the camera.

8. The radiation generating device according to claim 3, wherein the lock by the first locking mechanism is released when an operation instruction to release the lock is input.

9. The radiation generating device according to claim 2, wherein the trolley portion has a second locking mechanism capable of locking the rotation of the wheels.

10. The radiation generating device according to claim 9, wherein when the lock by the first locking mechanism is released, the lock by the second locking mechanism is performed.

11. The radiation generating device according to claim 2, wherein the first locking mechanism is an electromagnetic brake.

12. Equipped with a processor, The aforementioned processor, The radiation generating device according to claim 1, wherein the rotation of the main body by the rotation mechanism is controlled based on the inclination angle between the radiation source and the radiation image detection device, the imaging table, or the subject.

13. The aforementioned processor, The radiation generating device according to claim 12, wherein the difference between the azimuth angle of the radiation source detected by the geomagnetic sensor and the azimuth angle of the imaging table is derived as the tilt angle.

14. The main body is provided with a first magnet, The radiation generating device according to claim 1, wherein the first magnet is attracted to a second magnet provided on the imaging table, thereby aligning the radiation source and the imaging table.

15. The radiation generating device according to claim 1, wherein the rotating mechanism rotates about the vertical axis passing through at least one of the center of the main body and the focal point of the radiation.

Images