Method and system for adjusting examination table behavior of examinee

Abstract

Various methods and systems are provided for adjusting the behavior of a manually driven subject table (200) based on the intensity and / or direction of a magnetic field as detected by a passive sensor (202) of the manually driven subject table. In some embodiments, a medical imaging system includes: a manually driven subject table having a passive sensor configured to detect an intensity or direction of a magnetic field in real time; and a controller communicatively coupled to the passive sensor and configured with instructions stored on a non-transitory memory, the instructions, when executed, cause the controller to enhance user input transmission to one or more actuators of the manually driven subject table based on the intensity or direction of the magnetic field as detected by the passive sensor.

Description

Technical Field

[0001] Embodiments of the subject matter disclosed herein relate to magnetic resonance imaging, and more particularly to adjusting the behavior of a manually driven subject table in response to the strength and direction of a magnetic field of a magnetic system. Background Art

[0002] Magnetic resonance imaging (MRI) is a medical imaging modality that can create images of the inside of the human body without the use of X-rays or other ionizing radiation. MRI systems include superconducting magnets to generate a strong and uniform static magnetic field. 0 When the human body or part of the human body is placed in magnetic field B 0 When the nuclear spins associated with the hydrogen nuclei in the tissue water become polarized, with the magnetic moments associated with these spins preferentially oriented along the magnetic field B. 0 The MRI system also includes gradient coils that generate small amplitude, spatially varying magnetic fields with orthogonal axes to spatially encode magnetic resonance (MR) signals by generating characteristic resonant frequencies at each location in the body. The hydrogen nuclei are excited by radio frequency signals at or near the resonant frequency of the hydrogen nuclei, which adds energy to the nuclear spin system. When the nuclear spin relaxes back to its resting energy state, it releases the absorbed energy in the form of an RF signal. The RF signal (or MR signal) is detected by one or more RF coils and converted into an image using a reconstruction algorithm. Outside the MRI system (e.g., in a room where the MRI system is located), the magnitude and direction of the magnetic field are based on the location in the room. Summary of the invention

[0003] In one embodiment, a medical imaging system includes: a manually driven subject table having a passive sensor configured to detect, in real time, the strength or direction of a magnetic field; and a controller communicatively coupled to the passive sensor and configured with instructions stored on a non-volatile memory that, when executed, cause the controller to enhance user input transmitted to one or more actuators of the manually driven subject table based on the strength or direction of the magnetic field as detected by the passive sensor.

[0004] A method for controlling a manually driven subject table includes: receiving user input to the manually driven subject table; receiving the strength and direction of a magnetic field detected in real time using a passive sensor implemented in the manually driven subject table; accessing a field map representing a spatial distribution of the magnetic field and identifying a position and orientation of the manually driven subject table based on the strength and direction of the magnetic field, respectively; and enhancing transmission of the user input to one or more actuators of the manually driven subject table based on the position and orientation of the manually driven subject table.

[0005] It should be understood that the above brief description is provided to introduce in a simplified form selected concepts that are further described in the detailed description. It is not meant to identify key or essential features of the claimed subject matter, the scope of which is solely defined by the claims that follow the detailed description. Furthermore, the claimed subject matter is not limited to implementations that solve any disadvantages noted above or in any part of this disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0006] The present disclosure will be better understood by reading the following description of non-limiting embodiments with reference to the accompanying drawings, in which:

[0007] Figure 1 is a block diagram of an MRI system according to an embodiment of the present disclosure.

[0008] Figure 2 A manually driven subject examination table including a passive sensor according to an embodiment of the present disclosure.

[0009] Figure 3 A method for enhancing the transmission of user input to a user based on the strength or direction of a magnetic field as detected by a passive sensor according to an embodiment of the present disclosure is shown. Figure 2 A method of manually actuating one or more actuators of a subject examination table.

[0010] Figure 4 A method for calibrating a Figure 2 A method of attaching one or more passive sensors to an examination table of a subject.

[0011] Figure 5 An exemplary field diagram of a magnetic field according to an embodiment of the present disclosure is shown.

[0012] Figure 6 is a method for enhancing the transmission of user input to a user based on the strength or direction of a magnetic field as detected by a passive sensor according to an embodiment of the present disclosure Figure 2 Illustration of one or more wheel actuators of a manually driven subject examination table.

[0013] Figure 7 is a method for enhancing the transmission of user input to a user based on the strength or direction of a magnetic field as detected by a passive sensor according to an embodiment of the present disclosure Figure 2 Illustration of one or more docking system actuators of a manually driven subject examination table.

[0014] Figure 8 is a method for enhancing the transmission of user input to a user based on the strength or direction of a magnetic field as detected by a passive sensor according to an embodiment of the present disclosure Figure 2An illustration of one or more actuators of a table control panel of a manually actuated subject table.

[0015] Fig. 9 An embodiment of the present disclosure is shown in which a user input is enhanced based on the strength or direction of a magnetic field as detected by a passive sensor. Figure 2 An illustration of one or more actuators of an adjustable height mechanism of a manually-driven subject examination table for adjusting a planar angle of the manually-driven subject examination table.

[0016] Fig.10 An embodiment of the present disclosure is shown in which a user input is enhanced based on the strength or direction of a magnetic field as detected by a passive sensor. Figure 2 Illustration of one or more actuators of an adjustable height mechanism of a subject examination table that is manually actuated to adjust the height. DETAILED DESCRIPTION

[0017] The following description relates to various embodiments of systems and methods for a manually driven subject examination table, which has a passive sensor configured to detect the intensity or direction of a magnetic field in real time. A passive sensor can be any sensor that detects and responds to energy available in an environment without outputting energy itself to cause a response from the environment. The passive sensor described herein is configured to detect at least one of the intensity of a magnetic field or the direction of a magnetic field in real time. For example, the passive sensor can be a Hall sensor. The manually driven subject examination table also includes one or more actuators that are communicatively coupled to a controller. One or more actuators of the manually driven subject examination table can enhance the user input behavior of the manually driven subject examination table. For example, the controller can add, remove or enhance the maximum speed threshold of the manually driven subject examination table based on the position and orientation of the manually driven subject examination table as detected by the passive sensor. In response to the user input having a force that makes the speed of the manually driven subject inspection table equal to or exceed the maximum speed threshold, the controller can reduce the speed of the manually driven subject inspection table by actuating the brakes of one or more non-driven wheels or driving wheels, thereby enhancing the user input. For another example, the controller can guide the user input based on the position and orientation of the manually driven subject inspection table as detected by the passive sensor. For example, the manually driven subject inspection table may include a height actuator, which can enable the height of the manually driven subject inspection table to be adjusted via an adjustable height mechanism. In response to the passive sensor detecting that the manually driven subject inspection table is at an undesirable height based on the detected magnetic field, the controller can output a notification indicating the desired height adjustment to the display device. Additional actuators and corresponding enhancements to the user input behavior of the manually driven subject inspection table are described herein. In this way, the user input behavior of the manually driven subject inspection table can be enhanced based on the position (including proximity and orientation) of the manually driven subject inspection table relative to the magnetic field source. This may help position a manually driven subject table in a desired position relative to the magnetic field source.

[0018] Figure 1 An exemplary medical imaging system is shown which may include a manually driven subject table with passive sensors. Figure 2 An example of a manually driven subject table is shown that includes at least one passive sensor, a user input device, and one or more actuators, each actuator being communicatively coupled to a controller. Figure 3 A method for enhancing transmission of user input to one or more actuators of a manually driven subject table based on the strength or direction of a magnetic field as detected by a passive sensor is presented. Figure 4 shows the calibration Figure 2 A method of attaching one or more passive sensors to an examination table of a subject. Figure 5 An exemplary field diagram for determining a magnetic field that enhances user input transmission is shown. Figures 6 to 10 Exemplary enhancements of user input based on the strength and / or direction of a magnetic field as detected by a passive sensor are described. Figure 6 A diagram is shown of enhancing the transmission of user input to one or more wheel actuators based on the strength or direction of a magnetic field as detected by a passive sensor. Figure 7 A diagram is shown of enhancing the transmission of user input to one or more docking actuators of a manually driven subject table based on the strength or direction of a magnetic field as detected by a passive sensor. Figure 8 Illustration showing enhanced user input transmitted to a table control panel (TCP) including a display device to indicate desired adjustments to the position and / or orientation of a manually driven subject table based on the strength or direction of a magnetic field as detected by a passive sensor. Fig. 9 A diagram showing the enhancement of user input transmission to the TCP to indicate a desired adjustment to the planar angle of a manually driven subject table based on the strength or direction of a magnetic field as detected by a passive sensor. Fig.10 A diagram illustrating the enhancement of user input transmitted to the TCP to indicate a desired adjustment to the height of a manually driven subject table based on the strength or direction of a magnetic field as detected by a passive sensor.

[0019] In some embodiments, a manually driven subject table can be included in a medical system and can operate as a patient table on which a patient is positioned. As a patient table, the manually driven subject table can be used to position a patient relative to a medical imaging system (such as a magnetic resonance imaging (MRI) system) that generates a magnetic field for imaging the patient. Figure 1 MRI apparatus 10 is shown, which is an exemplary imaging system into which a manually driven subject table may be inserted, docked, or otherwise removably coupled. Figure 1 In the example of FIG. 2 , the manually driven subject table is referred to as a patient table 26 , as further described herein.

[0020] The MRI apparatus 10 includes a static magnetic field magnet unit 12, a gradient coil unit 13, an RF coil unit 14, an RF body or volume coil unit 15, a transmission / reception (T / R) switch 20, an RF driver unit 22, a gradient coil driver unit 23, a data acquisition unit 24, a controller unit 25, a patient examination table 26, a data processing unit 31, an operation console unit 32, and a display unit 33. In some embodiments, the RF coil unit 14 is a surface coil, which is a local coil that is usually placed near an anatomical structure of interest of a subject 16. Here, the RF body coil unit 15 is a transmission coil that transmits RF signals, and the local surface RF coil unit 14 receives MR signals. Therefore, the transmission body coil (e.g., the RF body coil unit 15) and the surface receiving coil (e.g., the RF coil unit 14) are independent but electromagnetically coupled components. The MRI apparatus 10 transmits an electromagnetic pulse signal to a subject 16 placed in an imaging space 18 where a static magnetic field is formed to perform scanning to obtain magnetic resonance signals from the subject 16. One or more images of the subject 16 may be reconstructed based on the magnetic resonance signals thus obtained by the scanning.

[0021] The static magnetic field magnet unit 12 includes, for example, an annular superconducting magnet installed in an annular vacuum container. The magnet defines a cylindrical space around the subject 16 and generates a constant static magnetic field B. 0 .

[0022] The MRI apparatus 10 further includes a gradient coil unit 13, which forms a gradient magnetic field in an imaging space 18 so as to provide three-dimensional position information for a magnetic resonance signal received by an RF coil array. The gradient coil unit 13 includes three gradient coil systems, each of which generates a gradient magnetic field along one of three spatial axes perpendicular to each other, and generates a gradient field in each of a frequency encoding direction, a phase encoding direction, and a slice selection direction according to an imaging condition. More specifically, the gradient coil unit 13 applies a gradient field in a slice selection direction (or a scanning direction) of the subject 16 to select a slice; and the RF body coil unit 15 or the local RF coil array can transmit an RF pulse to the selected slice of the subject 16. The gradient coil unit 13 also applies a gradient field in a phase encoding direction of the subject 16 to phase encode a magnetic resonance signal from a slice excited by an RF pulse. Then the gradient coil unit 13 applies a gradient field in a frequency encoding direction of the subject 16 to frequency encode a magnetic resonance signal from a slice excited by an RF pulse.

[0023] The RF coil unit 14 is disposed, for example, to surround a region to be imaged of the subject 16. In some embodiments, the RF coil unit 14 may be referred to as a surface coil or a receiving coil. A constant static magnetic field B is formed by the static magnetic field magnet unit 12.0 In the imaging space 18, the RF coil unit 15 transmits RF pulses as electromagnetic waves to the subject 16 based on a control signal from the controller unit 25, and thereby generates a high-frequency magnetic field B 1 This excites the proton spins in the slice to be imaged of the subject 16. The RF coil unit 14 receives the electromagnetic waves generated when the proton spins thus excited in the slice to be imaged of the subject 16 return to alignment with the initial magnetization vector as magnetic resonance signals. In some embodiments, the RF coil unit 14 may transmit RF pulses and receive MR signals. In other embodiments, the RF coil unit 14 may be used only to receive MR signals, and not to transmit RF pulses.

[0024] The RF body coil unit 15 is provided, for example, to surround the imaging space 18, and generates a main magnetic field B generated by the static magnetic field magnet unit 12 in the imaging space 18. 0 Orthogonal RF magnetic field pulses are used to excite the nucleus. Compared with the RF coil unit 14, which can be disconnected from the MRI device 10 and replaced with another RF coil unit, the RF body coil unit 15 is fixedly attached and connected to the MRI device 10. In addition, although the local coil (such as the RF coil unit 14) can transmit or receive signals only from a local area of ​​the subject 16, the RF body coil unit 15 generally has a larger coverage area. For example, the RF body coil unit 15 can be used to transmit or receive signals to the whole body of the subject 16. The use of a receive-only local coil and a transmission body coil provides uniform RF excitation and image uniformity at the expense of higher RF power deposited in the subject. For a transmit-receive local coil, the local coil provides RF excitation to the region of interest and receives MR signals, thereby reducing the RF power deposited in the subject. It should be understood that the specific use of the RF coil unit 14 and / or the RF body coil unit 15 depends on the imaging application.

[0025] The T / R switch 20 may selectively electrically connect the RF body coil unit 15 to the data acquisition unit 24 when operating in the receive mode, and may selectively electrically connect the RF body coil unit to the RF driver unit 22 when operating in the transmit mode. Similarly, the T / R switch 20 may selectively electrically connect the RF coil unit 14 to the data acquisition unit 24 when the RF coil unit 14 operates in the receive mode, and may selectively electrically connect the RF coil unit to the RF driver unit 22 when operating in the transmit mode. When both the RF coil unit 14 and the RF body coil unit 15 are used for a single scan, for example, if the RF coil unit 14 is configured to receive MR signals and the RF body coil unit 15 is configured to transmit RF signals, the T / R switch 20 may direct the control signal from the RF driver unit 22 to the RF body coil unit 15 while directing the received MR signal from the RF coil unit 14 to the data acquisition unit 24. The coil of the RF body coil unit 15 may be configured to operate in a transmit-only mode or a transmit-receive mode. The coils of the local RF coil unit 14 may be configured to operate in a transmit-receive mode or a receive-only mode.

[0026] The RF driver unit 22 includes a gate modulator (not shown), an RF power amplifier (not shown), and an RF oscillator (not shown), which are used to drive an RF coil (e.g., the RF coil unit 15) and form a high-frequency magnetic field in the imaging space 18. The RF driver unit 22 modulates an RF signal received from the RF oscillator into a signal of a predetermined timing having a predetermined envelope based on a control signal from the controller unit 25 and using the gate modulator. The RF signal modulated by the gate modulator is amplified by the RF power amplifier and then output to the RF coil unit 15.

[0027] The gradient coil driver unit 23 drives the gradient coil unit 13 based on a control signal from the controller unit 25, thereby generating a gradient magnetic field in the imaging space 18. The gradient coil driver unit 23 includes three driver circuit systems (not shown) corresponding to the three gradient coil systems included in the gradient coil unit 13.

[0028] The data acquisition unit 24 includes a preamplifier (not shown), a phase detector (not shown), and an analog / digital converter (not shown) for acquiring a magnetic resonance signal received by the RF coil unit 14. In the data acquisition unit 24, the phase detector uses the output of the RF oscillator from the RF driver unit 22 as a reference signal, performs phase detection on the magnetic resonance signal received from the RF coil unit 14 and amplified by the preamplifier, and outputs the analog magnetic resonance signal after the phase detection to the analog / digital converter to be converted into a digital signal. The digital signal thus obtained is output to the data processing unit 31.

[0029] The MRI apparatus 10 includes a table 26 for placing the subject 16 thereon. By moving the table 26 based on a control signal from the controller unit 25, the subject 16 can be moved inside and outside the imaging space 18.

[0030] The controller unit 25 includes a computer and a recording medium on which a program to be executed by the computer is recorded. The program, when executed by the computer, causes the various parts of the device to perform operations corresponding to a predetermined scan. The recording medium may include, for example, a ROM, a floppy disk, a hard disk, an optical disk, a magneto-optical disk, a CD-ROM, or a non-volatile memory card. The controller unit 25 is connected to the operation console unit 32 and processes an operation signal input to the operation console unit 32, and also controls the examination bed 26, the RF driver unit 22, the gradient coil driver unit 23, and the data acquisition unit 24 by outputting control signals to them. The controller unit 25 also controls the data processing unit 31 and the display unit 33 based on the operation signal received from the operation console unit 32 to obtain a desired image.

[0031] The operation console unit 32 includes a user input device such as a touch screen, a keyboard, and a mouse. The operator uses the operation console unit 32 to, for example, input such data as an imaging protocol and set an area where an imaging sequence will be executed. The data on the imaging protocol and the imaging sequence execution area are output to the controller unit 25.

[0032] The data processing unit 31 includes a computer and a recording medium on which a program to be executed by the computer to perform predetermined data processing is recorded. The data processing unit 31 is connected to the controller unit 25, and performs data processing based on a control signal received from the controller unit 25. The data processing unit 31 is also connected to the data acquisition unit 24, and generates spectrum data by applying various image processing operations to the magnetic resonance signals output from the data acquisition unit 24.

[0033] The display unit 33 includes a display device, and displays an image on a display screen of the display device based on a control signal received from the controller unit 25. The display unit 33 displays, for example, images regarding input items for which an operator inputs operation data from the operation console unit 32. The display unit 33 also displays a two-dimensional (2D) slice image or a three-dimensional (3D) image of the subject 16 generated by the data processing unit 31.

[0034] Although an MRI system is described by way of example, it should be understood that the present technology may also be useful in applications to other devices that generate a magnetic field and for which it is desirable to position a manually driven subject table (e.g., table 26) relative to the strength or direction of the magnetic field. The present discussion of the MRI imaging modality is provided merely as an example of a suitable modality having a magnetic field. Fig.10 Additional examples of devices that generate magnetic fields are described.

[0035] Go to Figure 2 , shows an embodiment of a manually driven subject examination table 200 with a passive sensor 202. The manually driven subject examination table 200 (also referred to herein as a "subject examination table" for brevity) may be Figure 1 The subject table 200 is an example of a patient table 26. The subject table 200 may additionally or alternatively be an example of a table for transporting a subject (such as a patient) throughout a medical environment that includes a magnetic field source (e.g., that generates a magnetic field in which the subject table 200 can be positioned) (such as an MRI device). The subject table 200 includes a bed 204, a handle 206, an adjustable height mechanism 208, one or more non-driven wheels, and a table control panel (TCP) 242. Additional elements of the subject table 200 are described herein. The subject table 200 is communicatively coupled to a controller 210 via a wired or wireless connection.

[0036] The passive sensor 202 can be any sensor that detects and responds to energy available in the environment, and does not output energy itself to cause a response from the environment. The passive sensor 202 described herein is configured to detect at least one of the intensity of the magnetic field or the direction of the magnetic field in real time. For example, the passive sensor 202 can be a Hall sensor. In some embodiments, the passive sensor 202 can be configured to detect both the intensity and direction of the magnetic field in real time. In addition, the passive sensor 202 detects the intensity and / or direction of the magnetic field in real time, and detects another parameter (e.g., intensity or direction) at periodic intervals. The passive sensor 202 is communicatively coupled to the controller 210 via a wired or wireless connection. In some embodiments, when the controller 210 is positioned in or on the subject inspection table 200, the passive sensor 202 is integrated in the controller 210, as further described herein. In some embodiments, the passive sensor 202 is positioned in or on the subject table 200 and is communicatively coupled to a controller 210 via a wired or wireless connection, the controller being positioned on a device other than the subject table 200, such as in a user interface device. In some embodiments, the subject table 200 may include more than one passive sensor 202. For example, as with respect to Fig. 9As further described, passive sensors may be positioned in the subject examination table 200 at each of the four corners of the bed 204, and the strength and magnitude of the magnetic field at each passive sensor may be compared to determine the angle of the bed 204, and therefore the horizontality.

[0037] The controller 210 includes a processor 240 configured to execute machine-readable instructions stored in the non-transitory memory 238 of the controller 210. The processor 240 may be single-core or multi-core, and the program executed by the processor 240 may be configured for parallel or distributed processing. In some embodiments, the processor 240 may optionally include separate components distributed throughout two or more devices, which may be remotely located and / or configured for collaborative processing. In some embodiments, one or more aspects of the processor 240 may be virtualized and executed by a remotely accessible networked computing device configured in a cloud computing configuration. In some embodiments, the processor 240 may include other electronic components capable of performing processing functions, such as a digital signal processor, a field programmable gate array (FPGA), or a graphics board. In some embodiments, the processor 240 may include multiple electronic components capable of performing processing functions. For example, the processor 240 may include two or more electronic components selected from a plurality of possible electronic components including the following items: a central processing unit, a digital signal processor, a field programmable gate array, and a graphics board. In yet other embodiments, the processor 240 may be configured as a graphics processing unit (GPU), including a parallel computing architecture and parallel processing capabilities. As further described herein, in some embodiments, the controller 210 may be integrated into the subject examination table 200. In other embodiments, the controller 210 may be a medical device (such as a Figure 1 A part of the MRI apparatus 10) (eg, the controller 210 may be an example of the controller unit 25).

[0038] The subject table 200 is defined herein as "manually driven", meaning that the motion and direction of movement of the subject table 200 are provided by user input. For example, the user may be a healthcare provider. The user input may be a thrust applied by the user, for example, at the handle 206, to the subject table 200 to drive the subject table 200 in a first direction indicated by the first arrow 212. The user may also apply a pulling force, for example, at the handle 206, to the subject table 200 to drive the subject table 200 in a second direction indicated by the second arrow 214. As further described herein, the subject table 200 includes one or more non-driven wheels that may rotate due to a force applied to the subject table 200 (e.g., from a user input) and may not be motor-driven or otherwise autonomously driven. In some embodiments, one or more non-driven wheels may be caster-like wheels and may be adjustable between a rolling state, a steering lock state, and a brake lock state. The rolling state enables the corresponding non-driven wheel to rotate 360 ​​degrees around the axis so that the subject examination table 200 can be driven in directions other than the first direction and the second direction. The steering state allows linear movement of the corresponding non-driven wheel (e.g., the first direction and / or the second direction). The brake lock state stops the rotation of the corresponding non-driven wheel, which can stop the movement of the subject examination table 200. The user can also change the direction of the subject examination table 200 (e.g., the subject examination table 200 can be rotated), for example, by applying a disproportionate thrust and / or pull force to the first side 216 and the second side 218 of the handle 206 when the non-driven wheel is in the rolling state. The direction of the subject examination table 200 can be changed (e.g., the subject examination table 200 can be rotated) while moving in the first direction or the second direction, or when the subject examination table 200 is stationary.

[0039] exist Figure 2 In the example of FIG. 1 , the non-driving wheels of the subject inspection table 200 include a first electronic caster 220, a second electronic caster 222, a third electronic caster 224, and a fourth electronic caster (not shown, opposite to the third electronic caster 224 and the first electronic caster 220). Figure 6 , Figure 7 and Fig. 9 The orientation of the subject inspection table 200 is shown (eg, the fourth electronic caster 620). The first electronic caster 220, the second electronic caster 222, the third electronic caster 224, and the fourth electronic caster 620 (eg, Figure 6 , Figure 7 and Fig. 9Each of the one or more electronic casters (collectively referred to as one or more electronic casters) may include a brake in each respective caster. Each of the one or more electronic casters may also include a caster actuator, as further described herein, which may enable the respective electronic caster to adjust between a rolling state, a brake lock state, and a steering lock state in response to user input and enhancement of the user input based on the strength and direction of the magnetic field as detected by the passive sensor 202, respectively.

[0040] Each of the one or more electronic casters can be coupled to the base 236 of the subject inspection table 200 in a certain manner so as to allow the wheel of each of the one or more casters to rotate around the corresponding axis, just like the nature of a conventional caster. The subject inspection table 200 also includes one or more caster actuators, which are configured to control the mode of the one or more electronic casters coupled thereto. For example, the one or more caster actuators include a first caster actuator 230 coupled to the first electronic caster 220, a second caster actuator 232 coupled to the second electronic caster 222, a third caster actuator 234 coupled to the third electronic caster 224, and a fourth caster actuator (not shown) coupled to the fourth electronic caster. Each of the one or more caster actuators can be communicatively coupled to the controller 210. As further described herein, the controller 210 can enhance the state change of the user input transmitted to the one or more caster actuators to control the corresponding caster based on the strength and direction of the magnetic field detected by the passive sensor 202, respectively. The controller may receive in real time the strength and / or direction of the magnetic field as detected by the passive sensor. That is, the controller may receive in real time the strength and / or direction.

[0041] The subject examination table 200 further includes a driving wheel 248. The driving wheel 248 is Figure 2 is shown as a dotted circle in FIG. 1 because the drive wheel 248 is Figure 2 The orientation of the subject table 200 shown may not be visible. The drive wheel 248 may be Figure 6 , Figure 7 and Fig. 9The subject table 200 is viewed in the orientation shown. The drive wheel 248 may include a small motor configured to provide a supplemental driving force to the user input force (e.g., the small motor may not be configured to drive the manually driven subject table 200 by itself). The small motor may be communicatively coupled to the controller 210 and may be controlled by a drive wheel actuator (not shown) to assist or limit rotation of the drive wheel 248 in response to the user input and to augment the user input based on the strength and direction of the magnetic field as detected by the passive sensor 202, respectively. For example, augmentation of the user input may include actuating the small motor to provide supplemental torque to the drive wheel 248, which may reduce the need for user-supplied force to move the subject table 200.

[0042] The manually driven subject table 200 may also include a hand brake 226. The hand brake 226 may be actuated by a user, for example, by depressing the hand brake 226, to stop the movement of the subject table 200. The hand brake 226 may additionally or alternatively be controlled via input (e.g., user input) received at a table control panel (TCP) 242, as further described herein. The hand brake 226 may be located at a first end 244 of the subject table 200. At a second end 246 opposite the first end 244, the subject table 200 may include a docking system (not shown) that enables the subject table 200 to dock with other devices and / or systems. For example, as relative to a Figure 7 As described, the subject examination table 200 can be connected to an MRI device (eg, Figure 1 MRI device 10) docking.

[0043] The subject table 200 may also include a table control panel (TCP) 242. The TCP may receive user input via one or more of a display screen, a microphone, a keyboard, a mouse, etc. The TCP may also provide output (such as notifications) via a display screen, an audible speaker, or other device for outputting notifications. Figure 2 In the illustrated embodiment, the TCP 242 may be positioned on the handle 206 of the subject examination table 200. In other embodiments, the TCP 242 may be positioned on the bed 204 of the subject examination table 200 or integrated into the bed. In further embodiments, the TCP 242 may be integrated into a device other than the subject examination table 200. For example, the TCP 242 may be integrated into a user device that is communicatively coupled to the controller 210 and communicatively coupled to the passive sensor 202 via the controller 210. The controller 210 is communicatively connected to the TCP 242 via a wired or wireless connection. The controller 210 may command the TCP 242 to output a notification in response to the strength or direction of the magnetic field as detected by the passive sensor 202. For example, as described herein with respect to Figures 8 to 9 As further described, the TCP 242 may output a noise, illuminate a light, or otherwise output a notification based on the strength or direction of the magnetic field as detected by the passive sensor 202 indicating that the subject table 200 is in an undesirable position or orientation.

[0044] A force sensor 250 (such as a load cell) may be integrated into the subject table 200 to detect a mechanical force (e.g., tension, pressure, compression, torque) applied (e.g., by a user via user input) to the subject table 200. For example, the force sensor 250 may be integrated into the handle 206 or at the first end 244 of the bed 204 of the subject table 200. The force sensor 250 may be communicatively coupled to the controller 210 via a wired or wireless connection. As further described herein, in addition to the strength and direction of the magnetic field as detected by the passive sensor 202, the mechanical force detected by the force sensor may be used to enhance the transmission of user input to one or more actuators of the subject table 200.

[0045] The adjustable height mechanism 208 of the subject examination table 200 couples the base 236 to the bed 204 and enables the bed 204 to be adjusted a variable distance 228 from the base 236. The adjustable height mechanism 208 may include, for example, a scissor lift, a telescopic lift, or other compact device for adjusting the variable distance. The adjustable height mechanism 208 may also include a motor (not shown) coupled to the device for assisting in adjusting the variable distance 228 and communicatively coupled to the controller 210. As described herein with respect to Figures 6 to 10 As further described, in response to the strength or direction of the magnetic field as detected by the passive sensor 202, the controller 210 may actuate a notification system (e.g., TCP 242) to output a notification indicating a desired action (e.g., user input) to adjust the variable distance 228. In some embodiments, the controller 210 may also command the actuation of a motor to provide supplemental assistance to the user input, thereby adjusting the variable distance 228 by expanding or contracting the corresponding device.

[0046] Go to Figure 3 , shows a method for controlling a manually driven subject table (eg, passive sensor 202) based on the strength or direction of a magnetic field as detected by a passive sensor of the subject table (eg, passive sensor 202). Figure 2 The method 300 is a method for a manually driven subject examination table 200. The manually driven subject examination table is positioned in a magnetic field, and a passive sensor can detect the strength or direction of the magnetic field in real time. The method 300 can be implemented by one or more of the above systems, including Figure 1 The controller unit 25 and / or Figure 2 The controller 210, or relative to Figures 1 to 2Thus, method 300 may be stored as executable instructions in a non-transitory memory such as Figure 2 238) and by a processor (such as Figure 2 processor 240) to execute.

[0047] A subject table with an integrated passive sensor can be positioned at different orientations relative to a magnetic field transmitting device (e.g., a magnet) at different times and at different distances from the magnetic field transmitting device. For example, the subject table can be positioned at a first distance from an MRI device (e.g., MRI device 10), wherein a handle of the subject table (e.g., handle 206) faces the MRI device and a bed of the subject table (e.g., bed 204) extends away from the MRI device. The subject table can be positioned at a second distance from the MRI device at different times, wherein the second distance is less than the first distance. The subject table can also be oriented so that the handle faces away from the MRI device and the bed extends toward the MRI device.

[0048] At 302, a user input is received by the manually driven subject table and detected by the controller. The user input can be, for example, a force applied to a handle of the manually driven subject table to push, pull and / or steer the manually driven subject table. The force can be detected by a force sensor (e.g., force sensor 250) (such as a load cell) and a signal is output to the controller that is proportional to the mechanical force (e.g., tension, pressure, compression, torque) applied by the user (e.g., user input). Additionally or alternatively, the user input can be provided via TCP and / or another user input device that is communicatively coupled to the controller.

[0049] At 304, the strength and / or direction of the magnetic field as detected by the passive sensor is received by the controller. The strength of the magnetic field as detected by the passive sensor may indicate a distance of the subject table from the magnet. The direction of the magnetic field as detected by the passive sensor may indicate an orientation of the subject table relative to the magnet. For example, when the direction of the magnetic field as detected by the passive sensor is directed away from the magnet, the subject table may be in a desired orientation (e.g., in an orientation in which the subject table may be docked to the MRI apparatus, such as relative to the magnet). Figure 6 to Figure 7 Alternatively, when the direction of the magnetic field as detected by the passive sensor is directed toward the magnet, the subject table may be in an undesirable orientation (e.g., a docking element of the subject table may be oriented away from a docking element of the MRI device, such as relative to the magnet). Figure 6 to Figure 7In some embodiments, the direction of the magnetic field as detected by the passive sensor of the subject table can indicate a detailed orientation of the subject table relative to the magnet. For example, when the magnetic field is directed toward the magnet and at an obtuse angle, the subject table can be positioned at an angle relative to the magnet and in a desired orientation (e.g., with the docking element of the subject table oriented toward the docking element of the MRI device). As further described herein, when the direction of the magnetic field as detected by the passive sensor is aligned with the magnet (e.g., with the subject table extending through the magnet), the subject table can be positioned at an angle relative to the magnet and in a desired orientation (e.g., with the docking element of the subject table oriented toward the docking element of the MRI device). Figure 1 When the subject table is aligned with the center line of the imaging space of the MRI device (e.g., aligned along a linear axis), the subject table can be in a desired position, at which the subject table can be aligned with the device having a magnet (e.g., Figure 1 MRI device, second subject examination table, etc.) docking.

[0050] In addition, when the strength of the magnetic field is relatively high compared to the strength of the magnet (e.g., 0.4 T for a 0.5 Tesla (T) magnet of an MRI device), the subject's examination table may be at a relatively small distance from the magnet (e.g., 1 meter (m)). When the strength of the magnetic field is relatively low compared to the strength of the magnet (e.g., 0.05 T for a 0.5 T magnet), the subject's examination table may be at a relatively large distance from the magnet (e.g., 5 m). In some embodiments, the passive sensor may be configured to detect both the strength and direction of the magnetic field in real time. In addition, the passive sensor may detect one of the strength and direction of the magnetic field in real time, and detect the other parameter (e.g., the strength or direction of the magnetic field) at periodic intervals. In some embodiments, the passive sensor may detect the strength or direction of the magnetic field in real time based on a selected parameter (e.g., user input via a user input device (e.g., operating console unit 32)).

[0051] At 306, a field map is accessed, wherein the field map represents the spatial distribution of the magnetic field, and the position and / or orientation of the subject table is identified using the field map and using the strength and / or direction of the magnetic field as detected by the passive sensor, respectively. The field map may be stored in a non-transitory memory of the controller (e.g., Figure 2 The non-volatile memory 238 of the controller 210 and accessed by a processor (e.g., processor 240) to compare the strength and / or direction of the magnetic field as detected by the passive sensor to the field map. The field map may also include the expected behavior of the subject table in different regions of the magnetic field. Figure 4 Describes the use of field diagrams to calibrate passive sensors and the expected behavior. Figure 5 Describe exemplary field diagrams.

[0052] At 308, the user input is transmitted to one or more actuators of the manually driven subject table based on the position and orientation identified at operation 306. Figures 6 to 10 Describe exemplary behaviors. The behaviors may include the ability of one or more electronic casters of the subject table to move linearly, turn / swivel, and / or remain stationary; the amount of supplemental torque provided to the drive wheel; the mode of the docking system of the subject table; the notification status of a notification system (e.g., TCP); and the actuation of an adjustable height mechanism. For example, a drive wheel actuator (e.g., a drive wheel actuator of a drive wheel) communicatively coupled to a controller may adjust the maximum drive speed of the manually driven subject table by adding, removing, or enhancing a maximum speed threshold of the manually driven subject table in response to the manually driven subject table being in a first region. In response to a user input having a force that causes the speed of the manually driven subject table to equal or exceed the maximum speed threshold, the controller may actuate the brakes of one or more non-drive wheels and / or drive wheels to reduce the speed of the manually driven subject table. As another example, the controller may adjust a set of one or more non-driven wheels and / or driven wheels to a steering lock position in response to the manually driven subject table being in a first orientation relative to a magnet generating a magnetic field as determined by a position and / or orientation detected by the passive sensor, in which each wheel in the set of one or more non-driven wheels and / or driven wheels is parallel to the length of the manually driven subject table. The controller may also prohibit the set of one or more non-driven wheels and / or driven wheels from changing between a steering lock state, a brake lock state, or a rolling state. Method 300 ends.

[0053] In this way, a controller communicatively coupled to the passive sensor can generate and deliver control parameters for one or more actuators of the manually driven subject table based on the strength or direction of the magnetic field as detected by the passive sensor. Actions input by a user (e.g., user input such as applying force to a handle of the manually driven subject table to drive and / or steer) can be augmented by the controller based on the strength and / or direction of the magnetic field as detected by the passive sensor.

[0054] Prior to implementing a method (e.g., method 300) for adjusting the behavior of a manually driven subject table based on the strength and / or direction of a magnetic field as detected by a passive sensor of the manually driven subject table, the passive sensor may be calibrated to establish a strength and direction of the magnetic field at which the subject table is at a desired distance and in a desired orientation relative to a magnet generating the magnetic field. The desired distance and desired orientation of the subject table may be, for example, the distance between the subject table and an MRI apparatus (e.g., Figure 1 MRI device 10) docking, the subject examination table and the subject transport equipment (e.g., bed, such as relative to Fig.10 ) and at a level with the subject transport device, etc. In some embodiments, calibrating the passive sensor can include generating a field map of the strength and direction of the magnetic field in a space (e.g., an imaging room) in which the subject table can be positioned.

[0055] Figure 4 A subject table for calibrating a manual drive (eg, Figure 2 In some embodiments, the subject table includes more than one passive sensor. In these embodiments, each of the one or more passive sensors of the subject table may be calibrated according to the method 400. The method 400 may be implemented by one or more of the above-described systems, including Figure 1 The controller unit 25 and / or Figure 2 Thus, the method 400 may be stored as executable instructions in a non-volatile memory such as Figure 2 238) and by a processor (such as Figure 2 processor 240) to execute.

[0056] At 402, a manually driven subject table is positioned at a desired distance and orientation relative to a magnet generating a magnetic field, and each of at least one passive sensor of the subject table is calibrated. When one or more electronic casters of the subject table are in a drive position or a steering position and the hand brake is disengaged, the user may position the subject table, for example, by applying force to a handle (e.g., handle 206) of the subject table. In some embodiments, calibrating each of the at least one passive sensor includes zeroing each of the passive sensors. For example, the strength of the magnetic field detected by the passive sensor when the subject table is positioned at a desired distance relative to the magnet (e.g., docking with an MRI device) may be set to be equal to zero. In addition, zeroing each of the passive sensors may include setting the direction of the magnetic field detected by the passive sensor when the subject table is positioned at a desired orientation relative to the magnet (e.g., docking with an MRI device) to null (e.g., no direction). As such, as the subject table moves away from the magnet (eg, the distance between the magnet and the subject table increases), the strength of the magnetic field detected by the passive sensor may decrease.

[0057] Some embodiments of the passive sensor may output the detected magnetic field strength as a negative number, where a larger negative number indicates a larger distance of the subject's examination table from the magnet. Alternatively, some embodiments of the passive sensor may output the magnetic field strength as a positive number, where a larger positive number indicates a larger distance of the subject's examination table from the magnet. The magnetic field strength as the output of the passive sensor may or may not be proportional to the actual strength of the magnetic field. For example, as the distance between the subject's examination table and the magnet increases at a linear rate, the strength of the magnetic field may decrease exponentially.

[0058] The direction of the magnetic field output by some embodiments of a passive sensor may be opposite to the true direction of the magnetic field. Figure 5 As shown in the field diagram of , the magnetic field can be polar and point away from the magnet at the south pole and toward the magnet at the north pole. However, in some embodiments of the passive sensor (where calibrating the passive sensor includes setting the direction of the magnetic field to null when the subject table is in a desired orientation and at a desired distance relative to the magnet), the direction of the magnetic field as detected by the passive sensor can point toward the magnet regardless of which magnetic pole the subject table is adjacent to. In other embodiments, the passive sensor can be calibrated to output the true direction of the magnetic field (e.g., showing the polarity of the magnet).

[0059] At 404, the passive sensor continuously (e.g., in real time) detects and records the strength and direction of the magnetic field as the manually driven subject table is moved throughout the magnetic field (e.g., to different locations in the imaging room). The subject table may be moved throughout the magnetic field to a plurality of predetermined locations (e.g., where the distance between the subject table and the magnet is known), and the strength and direction of the magnetic field as detected by the calibrated passive sensor and the known distance between the subject table and the magnet are recorded.

[0060] The desired behavior of the subject table may be associated with different positions of the subject table relative to the magnet. For example, when the distance between the subject table and the magnet is greater than or equal to 5 m, it may be desired that the subject's electronic casters be in a drive position and / or a steering position, which may enable the subject table to be manually driven toward the magnet. For another example, when the orientation of the subject table is undesirable (e.g., the docking system of the subject table is not aligned with the docking system of the MRI device), the notification system of the subject table may output a notification indicating the undesirable orientation. Figures 6 to 10 Describe additional examples of behavior.

[0061] At 406, the field map is updated to represent the calibrated passive sensor in the magnetic field and the field map is stored for future access. The field map may show the spatial distribution of the magnetic field, including strength and direction, such as relative to Figure 5As further described. For example, the strength of the magnetic field as detected by the passive sensor may be associated with a desired behavior for a given distance. As described with respect to operation 404, desired behaviors may be established for different distance ranges relative to the magnet (e.g., by a user, by a manufacturer, etc.). When the subject table is known to be within a given distance range, the strength or range of intensities of the magnetic field as detected by the passive sensor may be recorded. The strength or range of intensities may then be associated with the desired behavior for the given distance range. The association between behavior and detected magnetic field strength and / or direction made according to method 400 may be stored as a data set in a non-volatile memory of a controller (e.g., the non-volatile memory 238 of the controller 210) and called to adjust the behavior of the subject table (e.g., as relative to the subject table) based on the strength and / or direction of the magnetic field as detected by the passive sensor of the subject table. Figure 3 described).

[0062] Figure 5 An example of a field map 500 is shown that illustrates the spatial distribution of a magnetic field, including strength and direction. The field map 500 may be stored on a non-transitory memory (e.g., non-transitory memory 238) of a controller (e.g., controller 210) and accessed by a processor (e.g., processor 240) of the controller to identify a subject table (e.g., Figure 2 The position and orientation of the subject examination table 200).

[0063] Field diagram 500 includes a grid 502, a first dashed line ring 504, a second dashed line ring 506, and a magnet 508. Grid 502 represents a two-dimensional space in which a subject table can move / be moved (e.g., a top view of the floor of an imaging room). First dashed line ring 504 and second dashed line ring 506 represent magnetic fields generated and emitted by magnet 508. Magnet 508 may be, for example, an MRI device (such as Figure 1 MRI apparatus 10), a magnet attached to a subject transport device (such as relative to Fig.10 further described) or other magnets attached to a device relative to which the subject examination table can be positioned. Figure 5In the example of FIG. 5 , magnet 508 is a 0.5 T magnet, as indicated by the mark “0.5 T” at magnet 508 in grid 502. The magnetic field strength at different locations on grid 502 is marked. For example, the magnetic field strength is relatively strong (e.g., a larger T) at locations on grid 502 that are closer to magnet 508, and the magnetic field strength is relatively weak (e.g., a lower T) at locations on grid 502 that are farther away from magnet 508. The magnetic field is strongest (e.g., 0.5 T) at magnet 508. The arrows on each of the first dotted line ring 504 and the second dotted line ring 506 indicate the direction of the magnetic field. For example, the arrows on the first dotted ring 504 and the second dotted ring 506 on the left side 514 of the magnet 508 point away from the magnet 508, and the arrows on the first dotted ring 504 and the second dotted ring 506 on the right side 516 of the magnet 508 point toward the magnet 508, thereby illustrating the polarity of the magnet 508 (e.g., a south pole on the left side 514 and a north pole on the right side 516).

[0064] As compared to Figure 4 As described, desired behavior of the subject table may be associated with different positions of the subject table relative to the magnet. This may be represented in the field diagram 500 by one or more squares of the grid 502 having associated behaviors defined for the subject table. For example, the first square 520 may be a first distance (e.g., 2.5 m) from the magnet 508. At the first square 520, the strength of the magnetic field may be approximately 0.2 T, and the direction of the magnetic field may be parallel to the magnet 508. Thus, the desired behavior may include behavior that enables the subject table to move toward the magnet 508. The desired behavior may include adjusting one or more electronic casters of the subject table to a steering lock state, a brake lock state, or a rolling state. When such as relative to the magnet 508, the desired behavior may include adjusting one or more electronic casters of the subject table to a steering lock state, a brake lock state, or a rolling state. Figure 4 When calibrating one or more passive sensors of the subject table as described, the strength of the magnetic field as detected by at least one passive sensor may be recorded and associated with the first distance. In some embodiments, the strength of the magnetic field as detected by the passive sensor may be equal to or may not be equal to the true strength of the magnetic field (e.g., 0.2T), however, due to the calibration method, the expected behavior at the first distance may be associated with the detected strength. In addition, the detected direction of the magnetic field may also be recorded in association with the expected behavior. Thus, during execution of method 300, when the passive sensor detects the strength of the magnetic field associated with the first square 520 and the direction of the magnetic field, the controller (e.g., controller 210) may adjust the behavior of the subject table accordingly.

[0065] This article is relative to Figures 6 to 10 A method for adjusting a manually driven subject table (e.g., a subject table) based on the strength and / or direction of a magnetic field as detected by one or more passive sensors of the subject table is described. Figure 2 Another example of the behavior of the subject examination table 200). Figures 6 to 10 The described methods may be stored as executable instructions in a non-transitory memory such as Figure 2 238) and by a processor (such as Figure 2 processor 240) to execute.

[0066] Figure 6 A diagram 600 is shown in which the behavior of the subject table 200 is modified based on the proximity to the magnet of the MRI device 10 as detected by the passive sensor 202. In some embodiments, the subject table 200 may be in motion when the controller receives the strength and / or direction of the magnetic field. Based on the strength and / or magnitude of the received magnetic field (e.g., as detected by the passive sensor 202) and the information provided by the field map, the controller may determine that the subject table 200 is moving toward the magnet of the MRI device 10 at a first rate. The first rate may be greater than a first threshold rate, wherein the first threshold rate is a speed between 1 and 3 miles per hour (mph). In response to the first rate being greater than the first threshold rate, the controller may generate and output a control signal to actuate a caster actuator in one or more caster actuators, thereby adjusting the maximum allowable drive speed of the drive wheel to be less than the first threshold rate. For example, the first caster actuator 230 of the first electronic caster 220 may receive a control signal from the controller and reduce the maximum rotation speed of the first electronic caster 220. In some embodiments, the controller may additionally or alternatively generate and output control parameters for an auxiliary motor (not shown) to provide torque in a direction opposite to the direction of subject table movement to reduce the first velocity to less than a first threshold velocity.

[0067] The passive sensor 202 may continuously detect the strength and direction of the magnetic field when the subject table 200 is in motion, and the controller may continuously update the behavior of the subject table 200 based on the detected strength and direction of the magnetic field. For example, as the distance between the subject table 200 and the MRI apparatus 10 decreases, the maximum rotation speed of one or more electronic casters of the subject table 200 may be gradually reduced, thereby slowing down the driving speed of the subject table 200.

[0068] When the intensity of the magnetic field as detected by the passive sensor is less than a first intensity threshold, the controller may generate a control parameter and output it to each of the one or more casters of the subject's examination table to stop the electronic caster state change. For example, the control parameter may prevent each electronic caster of the subject's examination table from changing between a drive position, a steering position, and / or a brake position. Therefore, the electronic casters may remain in any of the drive position, steering position, and / or brake position in which they were located before the detected magnetic field intensity was less than the first intensity threshold. In this way, the docking of the subject's examination table with the MRI device may be simplified because the undesired movement of the subject's examination table may be prevented.

[0069] In another example, the act of adjusting one or more electronic casters of the subject table 200 based on the strength and / or direction of the magnetic field as detected by the passive sensor 202 may include adjusting for inaccuracies in the force sensors as the subject table 200 moves within the magnetic field. The subject table 200 may be idle (e.g., not in motion) and in a non-docked state with the MRI apparatus. A user may apply force to the subject table 200 (e.g., to a handle) to drive the subject table 200. When the hand brake 226 and the electronic drive (e.g., the electronic casters) are enabled, an electronic drive interruption (e.g., one or more electronic casters stop) may occur, in which case the controller may sample the passive sensor 202 and the force sensor of the subject table 200 to correct for inaccuracies in the force sensors. For example, if the controller determines that the velocity of the subject table 200 is greater than a threshold velocity and the strength of the magnetic field is greater than a threshold magnitude, the controller may execute a force sensor compensation algorithm to determine an amount of force to supplement (e.g., via an auxiliary motor of the subject table 200, such as relative to Figure 2 If the controller determines that the speed of the subject table 200 is less than a threshold speed or if the strength of the magnetic field is less than a threshold magnitude, the controller may not adjust the amount of the supplemental force.

[0070] In another embodiment, after the electronic drive is interrupted, the controller may sample the speed of the subject table and, in response to the speed being less than a threshold speed, disable the steering lock and the electronic drive. For example, one or more electronic casters of the subject table may be adjusted to a steering position and the auxiliary motor may be deactivated. In response to the speed being greater than the threshold speed, the controller may reduce the maximum speed of the subject table, as described above. In this way, as the distance of the subject table to the magnet decreases, the maximum electronic drive speed of the subject table may be reduced proportionally. As further discussed herein, as the subject table approaches the magnet, the height of the subject table may automatically increase.

[0071] Go to Figure 7, showing exemplary images illustrating a method for adjusting system behavior including behavior of a subject table 200 and an MRI apparatus (e.g., Figure 1 The first image 702 shows the subject table 200 and the MRI device 10 in a non-docked configuration. The second image 704 shows the subject table 200 and the MRI device 10 in a docked configuration.

[0072] The MRI device 10 includes a docking device 710 to which a subject table 200 (e.g., a docking system 720 of the subject table 200) can be docked. Based on the received strength of the magnetic field as detected in real time by the passive sensor 202 of the subject table 200, the controller can determine that the subject table 200 is within a first proximity range of the magnet, and therefore within a first proximity range of the MRI device 10. The first proximity range can be, for example, 1 to 2 meters. In addition, the controller can determine whether the subject table 200 is in a desired orientation for docking based on the direction of the magnetic field as detected by the passive sensor 202. When the controller determines that the subject table 200 is not in the desired orientation and / or is not within the first proximity range, the controller can generate a control signal and output the control signal to one or more caster actuators of the corresponding one or more electronic casters to adjust the electronic casters between the drive position and the steering position. This can enable the subject table 200 to be manually manipulated to the desired orientation and within the first proximity range.

[0073] In response to determining that the subject table 200 is within the first proximity range and has a desired orientation, the controller may generate and output a control signal to each of a docking actuator of a docking system 720 of the subject table 200 and a docking actuator of a dock 710 of the MRI apparatus 10 to prepare for dock engagement. For example, the dock 710 of the MRI apparatus 10 may open to receive the docking system 720 of the subject table 200, and the docking system 720 may extend from the subject table 200. In this way, the behavior of one or more devices may be adjusted according to the position and orientation of the subject table 200 as determined based on the strength and direction of the magnetic field as detected by the passive sensor 202 of the subject table 200, respectively.

[0074] Figure 8 The subject table is shown to be operated based on the strength and / or direction of the magnetic field as detected by the passive sensors of the subject table (eg, Figure 2 800 of a notification system for a subject examination table 200). The notification system may be Figure 2 TCP 242. Figure 8In the example of , TCP 242 includes a light that can illuminate to indicate to the subject that the examination table is in an undesirable position and / or orientation. Figure 2 As described, in other embodiments, TCP 242 may include additional or alternative notification devices, such as speakers for audio output and / or a screen for visual output.

[0075] As described above with respect to method 300, the controller may receive the strength and / or direction of the magnetic field in real time, and access the field map to determine that the manually driven subject table 200 is in a first orientation relative to the magnet generating the magnetic field (e.g., the magnet of the MRI device 10). Based on the field map, the first orientation may not allow the manually driven subject table to dock with the MRI device 10. The controller may generate and output notification control parameters for TCP 242, wherein the notification control parameters command the notification system to generate and output a notification indicating that the manually driven subject table 200 is in an undesired orientation for docking with the MRI device 10. For example, the light 802 of TCP 242 may be illuminated (e.g., a solid-state light, a flashing light, etc.). In response to determining that the subject table 200 is in the first orientation, the controller may also generate and output caster control parameters for one or more caster actuators of the electronic casters. The caster control parameters may command the caster actuator to adjust the corresponding electronic caster to a rolling state.

[0076] In this way, the subject table may output a notification (e.g., a visual indicator herein) based on the position and / or orientation of the subject table as determined using the strength and / or direction of the magnetic field detected by the passive sensor of the subject table, respectively. The notification may indicate to the user that the subject table is in an undesirable position and / or orientation. In some embodiments, the notification may also indicate that the behavior of the subject table has been adjusted by the controller to enable the subject table to move to a desired position and / or orientation.

[0077] Fig. 9 The invention shows adjusting a subject table (eg, Figure 2 900 is a diagram of the level of a bed of a subject examination table 200. Figure 2 As described, the subject examination table 200 may include more than one passive sensor. Fig. 9In the example of , the subject examination table 200 includes four passive sensors: a first passive sensor 910 in a first corner of the first end 244, a second passive sensor 912 in a second corner of the first end 244, a third passive sensor 914 in a third corner of the second end 246, and a fourth passive sensor 916 in a fourth corner of the second end 246. For example, the four passive sensors may be integrated in the bed 204 of the subject examination table 200. In some embodiments, the subject examination table 200 may also include a caster height adjuster in each of the first electronic caster 220, the second electronic caster, the third electronic caster, and the fourth electronic caster 620, wherein the caster height actuator may be communicatively coupled to the controller and may adjust the height of the corresponding electronic caster independently of the other electronic casters.

[0078] The controller may receive the strength and / or direction of the magnetic field in real time from each of the first passive sensor 910, the second passive sensor 912, the third passive sensor 914, and the fourth passive sensor 916. The controller may compare the strength and direction of the magnetic field as detected by each passive sensor to determine the orientation and levelness of the bed 204 of the subject table 200. The controller may generate and output control parameters (e.g., the same or different control parameters) for one or more of the passive sensors to adjust the lateral position and skew of the bed 204 based on the passive sensor output. For example, the control parameters may be sent to one or more caster actuators of the subject table 200 to actuate the caster height actuator to adjust the raised height of the base 236 of the subject table 200 at each electronic caster, as indicated by arrow 902. This may help to install the subject table 200 relative to the MRI apparatus 10, for example, to help adjust the bed 204 of the subject table 200 to be level. Additionally, in some embodiments, the controller may output data regarding the levelness of the bed 204 to a display device (eg, a user input device having a display) to indicate potential adjustments that may be made to level the bed 204 .

[0079] As briefly described herein, a manually driven subject table having one or more passive sensors configured to detect the magnitude and direction of a magnetic field in real time may be used with systems having a magnetic field other than an MRI apparatus. Fig.10An illustration 1000 of a subject table (e.g., subject table 200) used in conjunction with a patient transport device 1002 is shown. The patient transport device 1002 can be, for example, a hospital bed, a gurney, a stretcher, or other device for transporting a patient. The patient transport device 1002 can include a magnetic field generating device 1004 that generates a magnetic field. In other embodiments, a removable magnetic field generating device can be provided as the magnetic field generating device 1004 and can be removably attached to the patient transport device 1002. The magnetic field generating device 1004 can be a permanent magnet, or an electric device that generates a magnetic field. The passive sensor 202 of the subject table 200 can detect the strength and direction of the magnetic field generated by the magnet 1004 in the same manner as the passive sensor 202 detects the strength and direction of the magnetic field generated by the magnet of the MRI device as described herein.

[0080] As described above with respect to the method 300, the controller may receive the strength and / or direction of the magnetic field in real-time and access a field map to determine the position of the manually driven subject table 200 relative to the patient transport device 1002. Specifically, the passive sensor 202 may determine the height 1006 of the subject table 200 relative to the patient transport device 1002. For example, it may be desirable for the height 1006 of the subject table 200 to be equal to or slightly greater than (e.g., 1 to 5 inches greater) the height 1008 of the patient transport device 1002. The strength of the magnetic field as detected by the passive sensor 202 may indicate the height 1006 of the subject table 200 relative to the patient transport device 1002. The controller may generate and output control parameters that may command a motor or other actuator of an adjustable height mechanism 208 of the subject table 200 to increase or decrease the height 1006 of the subject table 200. This may facilitate automatic positioning of the subject table 200 at a desired height for patient transfers between the subject table 200 and the patient transport device 1002 .

[0081] The technical effect of adjusting the behavior of a manually driven subject table based on the strength and / or direction of a magnetic field as detected by a passive sensor of the subject table is improved sensor reliability, redundancy, and workflow simplification. The position, orientation, and height of the subject table may be automatically adjusted by a controller of the subject table based on the strength and direction of the magnetic field, thereby assisting user-driven positioning of the subject table, which may increase the accuracy of subject table positioning and reduce the time spent positioning and potentially repositioning the subject table.

[0082] The present disclosure also provides support for a medical imaging system, the medical imaging system comprising: a manually driven subject inspection table, the manually driven subject inspection table having a passive sensor configured to detect the strength or direction of a magnetic field in real time; and a controller, the controller being communicatively coupled to the passive sensor and configured with instructions stored on a non-transitory memory, the instructions when executed causing the controller to enhance user input based on the strength or the direction of the magnetic field as detected by the passive sensor to transmit one or more actuators of the manually driven subject inspection table. In a first example of the system, the magnetic field is generated by a magnet of a magnetic resonance imaging (MRI) system. In a second example of the system (optionally including the first example), the magnetic field is generated by a magnet attached to a subject transport device. In a third example of the system (optionally including one or both of the first example and the second example), the manually driven subject inspection table includes one or more non-driven wheels for positioning the manually driven subject inspection table. In a fourth example of the system (optionally including one or more or each of the first to third examples), the system further includes: an electronic caster wheel of the one or more non-driven wheels, the electronic caster wheel having a caster actuator, the caster actuator being communicatively coupled to the controller and configured to adjust the electronic caster wheel between a steering lock state, a brake lock state, or a rolling state based on the strength or the direction of the magnetic field as detected by the passive sensor. In a fifth example of the system (optionally including one or more or each of the first to fourth examples), the system further includes: a drive wheel having a drive wheel actuator, the drive wheel actuator being communicatively coupled to the controller and configured to adjust the maximum drive speed of the manually driven subject examination table based on the strength or the direction of the magnetic field as detected by the passive sensor. In a sixth example of the system (optionally including one or more or each of the first to fifth examples), the manually driven subject examination table further includes a force sensor integrated in a handle positioned at a first end of the manually driven subject examination table, the force sensor communicatively coupled to the controller. In a seventh example of the system (optionally including one or more or each of the first to sixth examples), the manually driven subject examination table includes an adjustable height mechanism, the adjustable height mechanism includes a height actuator, the height actuator is controlled by the controller to adjust the height of the manually driven subject examination table based on the strength and / or the direction of the magnetic field as detected by the passive sensor. In an eighth example of the system (optionally including one or more or each of the first to seventh examples), the system further includes: a notification system controlled by the controller to output a notification via the notification system based on the strength and / or the direction of the magnetic field as detected by the passive sensor.In a ninth example of the system (optionally including one or more or each of the first to eighth examples), the manually driven subject examination table includes a docking system having at least one docking actuator controlled by the controller to prepare the manually driven subject examination table for engagement or disengagement with a docking device of a magnetic field generating device based on the strength and / or the direction of the magnetic field as detected by the passive sensor. In a tenth example of the system (optionally including one or more or each of the first to ninth examples), the controller is integrated into the manually driven subject examination table.

[0083] The present disclosure also provides support for a method for controlling a manually driven subject table, the method comprising: receiving user input to the manually driven subject table; receiving the strength and direction of a magnetic field detected in real time using a passive sensor implemented in the manually driven subject table; accessing a field map representing the spatial distribution of the magnetic field and identifying the position and orientation of the manually driven subject table based on the strength and direction of the magnetic field, respectively; and enhancing the user input transmitted to one or more actuators of the manually driven subject table based on the position and orientation of the manually driven subject table. In a first example of the method, receiving the user input includes receiving a force applied to a handle of the manually driven subject table via a force sensor of the manually driven subject table to push, pull and / or steer the manually driven subject table. In a second example of the method (optionally including the first example), accessing the field map also includes accessing a desired enhancement of the user input to the manually driven subject table for the identified position and orientation of the manually driven subject table. In a third example of the method (optionally including one or both of the first and second examples), enhancing the transmission of the user input includes: determining whether the position of the manually driven subject examination table is within the first region of the magnetic field; in response to the manually driven subject examination table being within the first region, adding, removing or enhancing a maximum speed threshold of the manually driven subject examination table; and in response to the user input having a force that causes the speed of the manually driven subject examination table to equal or exceed the maximum speed threshold, actuating brakes of one or more non-driven wheels and / or driven wheels to reduce the speed of the manually driven subject examination table. In a fourth example of the method (optionally including one or more or each of the first to third examples), the method further includes: calibrating the passive sensor of the manually driven subject table by the following steps: docking the manually driven subject table to a magnet generating the magnetic field and zeroing the passive sensor of the manually driven subject table; undocking the manually driven subject table from the magnet; moving the manually driven subject table throughout the magnetic field; and detecting the strength and the direction of the magnetic field using the passive sensor; and updating the strength and the direction of the magnetic field at a location on the field map to represent the spatial distribution of the magnetic field.In a fifth example of the method (optionally including one or more or each of the first to fourth examples), enhancing the transmission of the user input includes: determining whether the position of the manually driven subject examination table is in a first orientation relative to the magnet generating the magnetic field, the first orientation enabling the manually driven subject examination table to dock with the magnet; in response to the manually driven subject examination table being in the first orientation, adjusting a set of one or more non-driven wheels and / or driven wheels to a steering lock position, wherein each wheel of the set of one or more non-driven wheels and / or the driven wheels is parallel to the length of the manually driven subject examination table; and prohibiting the set of one or more non-driven wheels and / or the driven wheels from changing between a steering lock state, a brake lock state, or a rolling state.

[0084] The present disclosure also provides support for a medical imaging system, the medical imaging system comprising: a magnet configured to selectively generate a magnetic field; a manually driven subject examination table having at least one passive sensor configured to detect the strength and / or direction of the magnetic field in real time; one or more non-driven wheels; driven wheels; a docking system; a table control panel (TCP); and a controller communicatively coupled to the passive sensor and configured with instructions stored on a non-transitory memory, the instructions, when executed, causing the controller to: The controller further comprises a controller for controlling the manually-driven subject table and a controller for controlling the manually-driven subject table. The controller further comprises a controller for controlling the manually-driven subject table and a controller for controlling the manually-driven subject table. The controller further comprises a controller for controlling the manually-driven subject table and a controller for controlling the manually-driven subject table. The controller further comprises a controller for controlling the manually-driven subject table and a controller for controlling the manually-driven subject table. In a first example of the system, the manually driven subject table includes at least one passive sensor on each of a first end of the manually driven subject table and a second end opposite the first end, and the controller is further configured with instructions stored on a non-transitory memory, which instructions, when executed, cause the controller to: compare the strength and the direction of the magnetic field identified by each passive sensor to determine the horizontality of the manually driven subject table, and generate a notification indicating the horizontality of the manually driven subject table and output the notification to the TCP. In a second example of the system (optionally including the first example), the magnet is positioned on one side of the subject transport table, and the controller is further configured with instructions stored on a non-transitory memory, which instructions, when executed, cause the controller to employ a gradient descent algorithm that uses the strength and the direction of the magnetic field identified by the at least one passive sensor to determine the desired height of the subject transport table and output a notification indicating the desired adjustment of the manually driven subject table via the TCP.

[0085] As used herein, the elements or steps listed in the singular and beginning with the word "one" or "an" should be understood as not excluding a plurality of the elements or steps, unless such exclusion is explicitly stated. In addition, the reference to "an embodiment" of the present disclosure is not intended to be interpreted as excluding the existence of additional embodiments that also include the described features. In addition, unless explicitly stated to the contrary, "comprising", "including" or "having" an embodiment of an element or multiple elements with a specific characteristic may include additional such elements that do not have the characteristic. The terms "including" and "in..." are used as the concise language equivalents of the corresponding terms "including" and "wherein". In addition, the terms "first", "second" and "third" etc. are only used as marks, and are not intended to impose numerical requirements or specific positional order on their objects.

[0086] As used herein, the terms "system" and "module" may include hardware and / or software systems that operate to perform one or more functions. For example, a module or system may include, or be included in, a computer processor, a controller, or other logic-based device that performs operations based on instructions stored on a tangible and non-transitory computer-readable storage medium (such as a computer memory). Alternatively, a module or system may include a hard-wired device that performs operations based on the hard-wired logic of the device. The various modules or systems shown in the figures may represent hardware that operates based on software or hard-wired instructions, software that instructs hardware to perform operations, or a combination thereof.

[0087] A "system" or "module" may include or represent hardware and related instructions (e.g., software stored on a tangible and non-transitory computer-readable storage medium (such as a computer hard drive, ROM, RAM, etc.) that perform one or more operations described herein. The hardware may include electronic circuitry that includes and / or is connected to one or more logic-based devices, such as microprocessors, processors, controllers, etc. These devices may be off-the-shelf devices that are appropriately programmed or instructed to perform the operations described herein in accordance with the instructions described above. Additionally or alternatively, one or more of these devices may be hardwired with logic circuitry to perform these operations.

[0088] This written description uses examples to disclose the disclosure, including the best mode, and also to enable a person of ordinary skill in the relevant art to practice the disclosure, including making and using any devices or systems and performing any included methods. The patentable scope of the disclosure is defined by the claims, and may include other examples that occur to a person of ordinary skill in the art. Such other examples are intended to fall within the scope of the claims if they have structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insignificant differences from the literal language of the claims.

Claims

1. A medical imaging system, comprising: A manually driven subject examination table (200) having a passive sensor (202) configured to detect the strength or direction of a magnetic field in real time; and A controller (210) communicatively coupled to the passive sensor and configured with instructions stored on a non-volatile memory (238) that, when executed, cause the controller to enhance user input transmitted to one or more actuators of the manually driven subject table based on the strength or the direction of the magnetic field as detected by the passive sensor.

2. The medical imaging system of claim 1, wherein the magnetic field is generated by a magnet of a magnetic resonance imaging (MRI) system (10).

3. The medical imaging system of claim 1, wherein the magnetic field is generated by a magnet attached to a subject transport device (1002).

4. The medical imaging system of claim 1, wherein the manually driven subject table comprises one or more non-driven wheels (220, 222, 224, 620) for positioning the manually driven subject table.

5. The medical imaging system of claim 4 , further comprising an electronic caster wheel of the one or more non-driven wheels, the electronic caster wheel having a caster actuator, the caster actuator being communicatively coupled to the controller and configured to adjust the electronic caster wheel between a steering lock state, a brake lock state, or a rolling state based on the strength or the direction of the magnetic field as detected by the passive sensor.

6. The medical imaging system of claim 1 , further comprising a drive wheel (248) having a drive wheel actuator, the drive wheel actuator being communicatively coupled to the controller and configured to adjust a maximum drive speed of the manually driven subject table based on the strength or the direction of the magnetic field as detected by the passive sensor.

7. The medical imaging system of claim 1 , wherein the manually driven subject examination table further comprises a force sensor (250) integrated into a handle (206) positioned at a first end of the manually driven subject examination table, the force sensor being communicatively coupled to the controller.

8. The medical imaging system of claim 1 , wherein the manually-driven subject examination table comprises an adjustable height mechanism (208), the adjustable height mechanism comprising a height actuator, the height actuator being controlled by the controller to adjust the height of the manually-driven subject examination table based on the strength and / or the direction of the magnetic field as detected by the passive sensor.

9. The medical imaging system of claim 1 , further comprising a notification system (242) controlled by the controller to output a notification via the notification system based on the strength and / or the direction of the magnetic field as detected by the passive sensor.

10. The medical imaging system of claim 1, wherein the manually driven subject table comprises a docking system (720) having at least one docking actuator controlled by the controller to prepare the manually driven subject table for engagement or disengagement with a docking device of a magnetic field generating device based on the strength and / or the direction of the magnetic field as detected by the passive sensor.

11. A method for controlling a manually driven subject examination table (200), the method comprising: receiving (302) user input to the manually driven subject examination table; receiving (304) the strength and direction of a magnetic field detected in real time using a passive sensor (202) implemented in a manually driven subject examination table; accessing (306) a field map (500) representing a spatial distribution of the magnetic field and identifying a position and an orientation of the manually driven subject table based on the strength and the direction of the magnetic field, respectively; as well as The user input transmitted to one or more actuators of the manually driven subject table is augmented (308) based on the position and the orientation of the manually driven subject table.

12. The method of claim 11, wherein receiving the user input comprises receiving a force applied to a handle of the manually driven subject table via a force sensor of the manually driven subject table to push, pull and / or steer the manually driven subject table.

13. The method of claim 11, wherein accessing the field map further comprises accessing a desired enhancement to the user input of the manually driven subject table for the identified position and orientation of the manually driven subject table.

14. The method of claim 11, wherein enhancing the transmission of the user input comprises: determining whether the position of the manually driven subject table is within a first region of the magnetic field; in response to the manually driven subject table being in the first region, adding, removing or enhancing a maximum speed threshold of the manually driven subject table; and in response to the user input having a force causing the speed of the manually driven subject table to equal or exceed the maximum speed threshold, actuating brakes of one or more non-driven wheels and / or driven wheels to reduce the speed of the manually driven subject table.

15. The method of claim 11, wherein enhancing the transmission of the user input comprises: determining whether the position of the manually-driven subject table is in a first orientation relative to a magnet generating the magnetic field, the first orientation enabling the manually-driven subject table to dock with the magnet; In response to the manually driven subject table being in the first orientation, adjusting a set of one or more non-driven wheels and / or driven wheels to a steering locked position, wherein each wheel of the set of one or more non-driven wheels and / or the driven wheels is parallel to a length of the manually driven subject table; and The set of one or more non-driven wheels and / or the driven wheels are inhibited from changing between a steering lock state, a brake lock state, or a rolling state.

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