Robot positioning method and apparatus, robot, storage medium, and program product

Abstract

The application relates to a robot positioning method and device, a robot, a storage medium and a program product. The method comprises the following steps: determining a target radio frequency pulse corresponding to a current positioning scan from a preset radio frequency pulse sequence when the tail end of the robot is located inside a target object; the radio frequency pulse sequence comprises a plurality of radio frequency pulses, and each radio frequency pulse has a different excitation range for a magnetic field region generated by a magnet; the target radio frequency pulse corresponding to the current positioning scan is different from a radio frequency pulse corresponding to a previous positioning scan; controlling an imaging device to apply the target radio frequency pulse to the target object and collecting a projection signal; and positioning the tail end of the robot based on the projection signal. In the embodiment of the application, a plurality of radio frequency pulses with different excitation ranges are preset, and different radio frequency pulse cycles are used for tissue excitation, so that the tissue signals of the same region are not repeatedly excited, the positioning accuracy is improved, and the positioning refresh rate is also improved.

Description

Technical Field

[0001] This application relates to the field of positioning technology, and in particular to a robot positioning method, apparatus, robot, storage medium, and program product. Background Technology

[0002] A magnetic robot (or magnetically controlled robot) is a robot with a magnet at its end effector, which uses magnetic drive and magnetic navigation technology to achieve robot positioning. The basic principle of magnetic navigation is as follows: after the robot enters the body of the experimental object, the dipole field distribution of the end magnet itself will form a magnetic field within a certain range. After applying a radio frequency pulse of a specific frequency to the experimental object through an imaging device, the tissue within the magnetic field will be excited. The position of the robot can be determined based on the projection signal of the excited tissue.

[0003] However, when the robot stops moving or moves only slightly, the tissues in the magnetic field around the robot are repeatedly excited, leading to saturation and weakening of the projection signal, which seriously affects the accuracy of the robot's positioning. Summary of the Invention

[0004] Therefore, it is necessary to provide a robot positioning method, device, robot, computer-readable storage medium, and computer program product that can improve the accuracy of robot positioning in response to the above-mentioned technical problems.

[0005] In a first aspect, this application provides a robot positioning method, wherein the end effector of the robot is provided with a magnet, comprising:

[0006] When the robot's end effector is located inside the target object, the target radio frequency pulse corresponding to the current positioning scan is determined from a preset radio frequency pulse sequence; the radio frequency pulse sequence includes multiple radio frequency pulses, and each radio frequency pulse generates a different excitation range of the magnetic field region of the magnet; the target radio frequency pulse corresponding to the current positioning scan is at least different from the radio frequency pulse corresponding to the previous positioning scan;

[0007] The imaging device is controlled to apply a target radio frequency pulse to the target object and to acquire the projection signal;

[0008] Positioning of the robot's end effector is based on projection signals.

[0009] In one embodiment, determining the target radio frequency pulse corresponding to the current positioning scan from a preset radio frequency pulse sequence includes:

[0010] According to the preset radio frequency pulse sequence, the target radio frequency pulse corresponding to the current positioning scan is determined from the preset radio frequency pulse sequence.

[0011] In one embodiment, the preset radio frequency pulse sequence is arranged in descending or ascending order of frequency.

[0012] In one embodiment, the radio frequency pulse sequence is obtained by means of:

[0013] The frequency range is determined based on the magnetic properties of the magnet;

[0014] The number of radio frequency pulses is determined based on the recovery time of the magnetization vector of the excited tissue and the excitation time of the radio frequency pulse.

[0015] The radio frequency pulse sequence is determined based on the frequency range and the number of radio frequency pulses.

[0016] In one embodiment, the radio frequency pulse sequence includes multiple radio frequency pulses arranged sequentially according to their frequency magnitude, and the distance between the excitation ranges of adjacent radio frequency pulses is less than a preset distance threshold.

[0017] In one embodiment, the bandwidths of the radio frequency pulses in the radio frequency pulse sequence are the same or at least partially different.

[0018] Secondly, this application also provides a robot positioning device, wherein the end effector of the robot is provided with a magnet, comprising:

[0019] The determination module is used to determine the target radio frequency pulse from a preset radio frequency pulse sequence when the robot's end effector is located inside the target object; the radio frequency pulse sequence includes multiple radio frequency pulses of different frequencies, and the excitation range of the magnetic field region generated by each radio frequency pulse on the magnet is different;

[0020] The control module is used to control the imaging device to apply target radio frequency pulses to the target object and to acquire projection signals;

[0021] The positioning module is used to locate the robot's end effector based on projection signals.

[0022] Thirdly, this application also provides a robot, including a memory and a processor, wherein the end of the robot is provided with a magnet, the memory stores a computer program, and the processor executes the computer program to implement the steps of the robot positioning method in the first aspect above.

[0023] Fourthly, this application also provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of the robot localization method described in the first aspect above.

[0024] Fifthly, this application also provides a computer program product, including a computer program that, when executed by a processor, implements the steps of the robot localization method described in the first aspect above.

[0025] The aforementioned robot positioning method, apparatus, computer equipment, storage medium, and computer program product, when the robot's end effector is located inside the target object, determine the target radio frequency pulse corresponding to the current positioning scan from a preset radio frequency pulse sequence. The radio frequency pulse sequence includes multiple radio frequency pulses, and each radio frequency pulse generates a different excitation range of the magnetic field region of the magnet. In addition, the target radio frequency pulse corresponding to the current positioning scan is at least different from the radio frequency pulse corresponding to the previous positioning scan. Then, the imaging device is controlled to apply the target radio frequency pulse to the target object and acquire the projection signal. The robot's end effector is positioned based on the projection signal. That is to say, in the embodiments of this application, multiple radio frequency pulses with different excitation ranges are preset. During each positioning scan, different radio frequency pulses are used to excite tissue signals in different excitation ranges. In this way, tissue signals in the same area will not be continuously and repeatedly excited, but will undergo magnetization vector recovery after a certain period of time after being excited. Therefore, it is possible to avoid saturation due to repeated excitation of tissue signals in the same area, and always maintain the strength of the positioning projection signal, thereby improving the accuracy of robot positioning during robot movement, especially when the robot is stationary or the movement amplitude is small. In addition, by adopting the positioning scheme proposed in this application, since the excited tissue has a certain magnetization vector recovery time, the refresh rate of robot positioning can be improved, and robot positioning can be achieved with a higher refresh rate, avoiding large deviations between the positioning results and the actual position of the robot, which could lead to adverse consequences. Attached Figure Description

[0026] To more clearly illustrate the technical solutions in the embodiments or related technologies of this application, the accompanying drawings used in the description of the embodiments or related technologies will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0027] Figure 1 This is a diagram illustrating the application environment of a robot localization method in one embodiment;

[0028] Figure 2 This is a flowchart illustrating a robot localization method in one embodiment;

[0029] Figure 3 This is a schematic diagram of the magnetic navigation and positioning principle of a magnetic robot in one embodiment;

[0030] Figure 4 This is a schematic diagram of the positioning and scanning of a radio frequency pulse sequence in one embodiment;

[0031] Figure 5 This is a flowchart illustrating the robot localization method in another embodiment;

[0032] Figure 6 This is a structural block diagram of a robot positioning device in one embodiment;

[0033] Figure 7 This is a diagram of the internal structure of a robot in one embodiment. Detailed Implementation

[0034] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0035] Miniature magnetic robots (or magnetically controlled robots) utilize magnetic actuation and magnetic navigation technology to achieve robot localization. The basic principle of magnetic navigation localization is as follows: It leverages the local frequency shift created by the dipole field distribution within the magnetic robot itself (i.e., a shift in the precession frequency of protons in the tissue within the dipole field distribution range), combined with an excitation pulse of a specific frequency (also known as a radio frequency pulse), to excite the local area covered by the dipole field. Orthogonal three-dimensional projection signals are then collected to achieve the magnetic robot's localization. This method relies on the dipole field distribution of the magnetic robot.

[0036] When the magnetic robot enters the experimental subject's body, the tissue within the range of the magnetic robot's dipole field distribution is repeatedly excited during magnetic navigation and positioning. If the magnetic robot's movement amplitude is small and the feedback rate (i.e., refresh rate) is fast, the surrounding tissue will gradually become saturated, resulting in a decrease in the positioning signal and susceptibility to background noise interference, thus affecting the accuracy of positioning. Furthermore, considering the recovery of the magnetization vector of the excited tissue, projection scanning requires a certain amount of time to ensure signal recovery, which also limits the refresh rate of the magnetic navigation and positioning method, impacting the real-time performance of control.

[0037] Therefore, how to avoid repeated excitation of the tissue, improve the accuracy of the positioning signal, and increase the refresh rate of magnetic navigation positioning are the core technical problems that urgently need to be solved.

[0038] Based on this, this application proposes a navigation and positioning method for a magnetic robot. By controlling the frequency and bandwidth of radio frequency pulses, the method avoids repeated excitation of the same tissue area, thereby improving the accuracy and refresh rate of magnetically controlled positioning. Specifically, by adjusting the frequency and bandwidth of the radio frequency pulses applied by the imaging device to the imaging object during magnetic navigation, signal saturation of surrounding tissues during positioning is alleviated. At a high refresh rate, this effectively enhances the strength of the positioning signal, thereby improving positioning accuracy.

[0039] The robot localization method provided in this application embodiment can be applied to, for example... Figure 1In the illustrated application environment, the robot positioning method can be applied to robot 102, which can be a micro magnetic robot. A magnet is located at the end of robot 102. During movement, robot 102 can acquire the position of its end in real time using magnetic navigation and positioning technology, thus achieving navigation and positioning. Optionally, robot 102 can also include a display that shows the robot's position acquired through navigation and positioning in real time; alternatively, robot 102 can be connected to an external display. After acquiring the robot's position, the position can be sent to the display in real time for display, allowing the user to promptly grasp the robot's current position and providing a positional reference for subsequent (automatic or manual) operation and control of the robot.

[0040] For example, the robot localization method can also be applied to other computer devices besides robots. The computer device can be an imaging device or a control device that is communicatively connected to the imaging device. When navigating and locating the robot, the computer device can control the imaging device to apply a certain radio frequency pulse to the imaging object where the robot is located, and obtain the orthogonal three-dimensional projection signal (or positioning signal) collected by the imaging device. Then, based on the projection signal, the current position of the robot is determined, and the robot localization is achieved.

[0041] In the case where the computer device is the control device, the control device can be a terminal or a server. The terminal can be, but is not limited to, various personal computers, laptops, smartphones, tablets, and portable wearable devices. Portable wearable devices can be smartwatches, smart bracelets, head-mounted devices, etc. The server can be implemented using a standalone server or a server cluster composed of multiple servers, such as a local server, a cloud server, or a remote server.

[0042] In one exemplary embodiment, such as Figure 2 As shown, a robot localization method is provided, which can be applied to... Figure 1 The following steps, 202 to 206, are used as an example to illustrate the process of building a robot.

[0043] Step 202: When the robot's end effector is located inside the target object, determine the target radio frequency pulse corresponding to the current positioning scan from the preset radio frequency pulse sequence.

[0044] The radio frequency pulse sequence includes multiple radio frequency pulses, and each radio frequency pulse generates a different range of magnetic field regions on the magnet; the target radio frequency pulse corresponding to the current positioning scan is at least different from the radio frequency pulse corresponding to the previous positioning scan.

[0045] During the magnetic navigation of a magnetic robot, the imaging region of an imaging device, such as a magnetic resonance imaging (MRI) device, is corrected with a uniform field (e.g., a B0 field). Ideally, the precession frequency of protons in the imaging region is... ,in, The gyromagnetic ratio is expressed in MHz / T. As the target object enters the imaging region, the magnetorobot subsequently enters the target object's tissue. Due to the dipole field distribution of the magnetorobot itself, the proton precession frequency in the tissue surrounding the magnetorobot will shift, becoming... , where F represents the dipole field distribution. This precession frequency shift of the surrounding tissue is the key to achieving magnetic robot localization.

[0046] Conventional methods, with a fixed bandwidth for the radio frequency pulse, require an initial frequency of [missing information]. Based on this (the radio frequency pulse frequency being consistent with the proton precession frequency is a necessary condition for generating magnetic resonance), by adding a fixed frequency offset... This method can excite signals in the tissue surrounding the magnetic robot, while other background areas remain unexcited. Signals are read out in three orthogonal directions, corresponding to one-dimensional projections. By using these one-dimensional projections and taking the midpoint of the signal peak, the three-dimensional coordinates x, y, and z can be obtained, which represents the spatial position of the magnetic robot.

[0047] However, if the magnetic robot stops moving or moves only a small amount, the tissue signal near the stopping point will be continuously and repeatedly excited, eventually becoming saturated. This is very detrimental to positioning because once the tissue signal is saturated, the projection signal weakens, severely affecting the accuracy of positioning. Furthermore, conventional methods struggle to reduce the scanning time of one-dimensional projection, and the magnetization vector of the tissue requires time to recover. Therefore, the positioning refresh rate of magnetic navigation is limited, making it difficult to achieve high refresh rate control.

[0048] In this embodiment of the application, unlike conventional methods that fix the RF bandwidth and frequency offset, N sets of frequency offsets are taken ( ) and bandwidth ( The combination of these elements forms a radio frequency pulse sequence. Each positioning scan involves a one-dimensional projection in three orthogonal directions, taking a set of frequency offsets and bandwidth combinations, and repeating this process N times. For each set of frequency offsets and bandwidth combinations, a specific frequency band of dipole field distribution near the magnetic robot is excited. Thus, each positioning scan originates from a different tissue region, preventing the same tissue region from being repeatedly excited and saturated. Furthermore, under N-step combinations, the signal region excited by the same set of frequency offsets and bandwidths will be excited again after N steps. Therefore, the recovery time is N times the time of a single positioning scan, which is beneficial for the recovery of already excited tissue signals, ensuring that the optimal tissue signal state is maintained for subsequent repeated excitations, thereby ensuring positioning accuracy.

[0049] Based on this radio frequency (RF) pulse sequence, a different RF pulse can be identified from this sequence during each positioning scan, serving as the target RF pulse for the current positioning scan. The target RF pulse for the current positioning scan is different from the RF pulse used in the previous positioning scan or the previous M positioning scans, where M is less than N. For example, when N is 5 (i.e., 5 different RF pulses) are used in a cyclic scan, each RF pulse can be used sequentially in a fixed order for the positioning scan. The first RF pulse will be used in the first and sixth positioning scans, and the second RF pulse will be used in the second and seventh positioning scans.

[0050] Of course, these five different radio frequency pulses can also be used in a non-fixed order. For example, the first radio frequency pulse can be used in the first and fourth positioning scans. Assuming that the time of the five positioning scans is exactly the recovery time of the magnetization vector of the excited tissue, the first radio frequency pulse can be used in the fourth positioning scan. At this time, the magnetization vector of the tissue signal in the tissue area excited by the first radio frequency pulse (i.e., the excitation range corresponding to the first radio frequency pulse) has not been fully recovered. However, since the magnetization vector of the tissue signal has recovered for a certain period of time, its saturation is reduced compared to the continuous excitation of the tissue area, and the intensity of the projected signal is not too weak, which can also meet the requirements of positioning accuracy to a certain extent.

[0051] Step 204: Control the imaging device to apply a target radio frequency pulse to the target object and acquire the projection signal.

[0052] For example, when performing the current positioning at a certain refresh rate, the imaging device can be controlled to apply the target radio frequency pulse to the target object and collect the projection signal excited by the target radio frequency pulse, that is, the projection signal in three orthogonal directions; wherein, the three orthogonal directions may include the X-axis direction, the Y-axis direction and the Z-axis direction.

[0053] Step 206: Position the robot's end effector based on the projection signal.

[0054] For example, when the projected signals of three orthogonal directions under the excitation of the target radio frequency pulse are obtained, the one-dimensional projection of the projected signals of the three orthogonal directions can be used, and the middle position of the signal peak can be taken to obtain the three-dimensional coordinates (x, y, z), such as... Figure 3 As shown, this is the spatial position of the magnetic robot inside the target object during the current positioning.

[0055] In the aforementioned robot localization method, when the robot's end effector is located inside the target object, a target radio frequency (RF) pulse corresponding to the current localization scan is determined from a preset RF pulse sequence. The RF pulse sequence includes multiple RF pulses, each with a different excitation range for the magnetic field region generated by the magnet. Furthermore, the target RF pulse corresponding to the current localization scan is at least different from the RF pulse corresponding to the previous localization scan. Next, the imaging device is controlled to apply the target RF pulse to the target object and acquire the projection signal. The robot's end effector is then localized based on the projection signal. In other words, this embodiment pre-sets multiple RF pulses with different excitation ranges. During each localization scan, different RF pulses are used to excite tissue signals within different excitation ranges. This prevents the tissue signals in the same area from being repeatedly and continuously excited. Instead, the magnetization vector recovers after a certain period of time following excitation. Therefore, saturation due to repeated excitation of the same area's tissue signals is avoided, maintaining the strength of the localization projection signal and improving the accuracy of robot localization, especially when the robot is stationary or has a small range of motion. In addition, by adopting the positioning scheme proposed in this application, since the excited tissue has a certain magnetization vector recovery time, the refresh rate of robot positioning can be improved, and robot positioning can be achieved with a higher refresh rate, avoiding large deviations between the positioning results and the actual position of the robot, which could lead to adverse consequences.

[0056] In an exemplary embodiment, step 202 above, "determining the target radio frequency pulse corresponding to the current positioning scan from a preset radio frequency pulse sequence," may include:

[0057] According to the preset radio frequency pulse sequence, the target radio frequency pulse corresponding to the current positioning scan is determined from the preset radio frequency pulse sequence.

[0058] For example, the preset radio frequency pulse sequence can be arranged in descending or ascending order of frequency, or it can be a custom pulse application order. For instance, in a preset radio frequency pulse sequence, each radio frequency pulse can be sorted in descending (or ascending) frequency order, and each pulse can be selected sequentially for positioning scanning according to this order. Alternatively, after sorting each radio frequency pulse in descending (or ascending) frequency order to form a radio frequency pulse sequence, the user can also customize the pulse application order of each pulse. For example, if the radio frequency pulse sequence includes 5 radio frequency pulses arranged in descending order of frequency, the preset radio frequency pulse sequence can be 1, 2, 3, 4, 5, or 5, 4, 3, 2, 1, or 1, 3, 5, 2, 4, or 1, 2, 5, 3, 4, etc.

[0059] Based on a preset radio frequency (RF) pulse sequence, the target RF pulse corresponding to the current positioning scan can be determined from the preset RF pulse sequence during each positioning scan. This allows for cyclic positioning scans of each RF pulse sequentially according to the preset RF pulse sequence, with each RF pulse being excited again on its Nth excitation. This provides sufficient recovery time for the magnetization vector of the tissue signal within the excited range, preventing the tissue signal from becoming saturated and causing inaccurate positioning.

[0060] refer to Figure 4 As shown, in a preset radio frequency pulse sequence that includes three radio frequency pulses with different frequency offsets and bandwidths, such as A(f1, BW1), B(f2, BW2), and C(f3, BW3), and the preset radio frequency pulse order is A, B, and C, the first positioning scan can use radio frequency pulse A, the second positioning scan can use radio frequency pulse B, and the third positioning scan can use radio frequency pulse C. Of course, the fourth positioning scan will use radio frequency pulse A again, the fifth positioning scan will use radio frequency pulse B again, and the sixth positioning scan will use radio frequency pulse C again, and so on, until the positioning is completed.

[0061] It should be noted that, Figure 4 The number of RF pulses and excitation range shown are merely examples and are not applicable to all situations. Figure 4The radio frequency pulse distribution shown has a higher frequency for pulses closer to the center of the coordinate axis and a lower frequency for pulses farther away from the center. Furthermore, the bandwidth of each radio frequency pulse can be the same or different, meaning the width of the excitation range for each pulse can be the same or different. The excitation ranges corresponding to adjacent radio frequency pulses can be closely adjacent, have a small overlap, or have a small gap. Of course, the utilization rate of the tissue region within the dipole field distribution is highest when the excitation ranges corresponding to adjacent radio frequency pulses are closely adjacent.

[0062] In this embodiment, the application order of each radio frequency pulse in the preset radio frequency pulse sequence can be pre-set, so that the radio frequency pulse sequence can be used cyclically according to a certain radio frequency pulse order. In this way, the tissue area excited each time the positioning scan is different. The tissue area that is re-excited is excited again after obtaining the recovery time, which can avoid the saturation phenomenon caused by repeated excitation of the tissue area, resulting in inaccurate positioning. Therefore, it can not only improve the positioning accuracy, but also improve the positioning refresh rate.

[0063] In an exemplary embodiment, for the above-mentioned radio frequency pulse sequence, a method for obtaining the radio frequency pulse sequence is also provided, such as... Figure 5 As shown, the above method may further include steps 502 to 506. Wherein:

[0064] Step 502: Determine the frequency range based on the magnetic properties of the magnet.

[0065] The frequency range refers to the range of frequencies that the dipole field distribution of a magnet can cover. Different magnets have different magnetic properties, and therefore, their corresponding frequency ranges will also be different.

[0066] When determining multiple excitation pulses suitable for a certain magnet, the frequency range corresponding to the multiple excitation pulses can be determined first based on the magnetic properties of the magnet, that is, excitation pulses with different center frequencies can be selected within this frequency range.

[0067] Step 504: Determine the number of radio frequency pulses based on the recovery time of the magnetization vector of the excited tissue and the excitation time of the radio frequency pulse.

[0068] During positioning scanning, the imaging device needs to apply radio frequency pulses of a certain frequency and bandwidth to the target object and continue to excite for a certain duration to excite and acquire signals; for example, the excitation duration corresponding to each radio frequency pulse can be consistent, such as continuous excitation for 1 second.

[0069] When different tissues are excited by radio frequency pulses, the recovery time of the magnetization vector of the tissue may vary. For example, the type of tissue can be determined first, and the recovery time of the magnetization vector of the excited tissue can be determined according to the type of tissue. The recovery time of the magnetization vector of different tissues can be obtained in advance through experimental or theoretical measurement.

[0070] Given the recovery time of the magnetization vector of the excited tissue and the excitation time of the radio frequency pulse, the number of radio frequency pulses can be determined based on the quotient of the recovery time of the magnetization vector of the excited tissue and the excitation time of the radio frequency pulse. If the quotient of the recovery time of the magnetization vector of the excited tissue and the excitation time of the radio frequency pulse is an integer, the number of radio frequency pulses can be that quotient value. If the quotient of the recovery time of the magnetization vector of the excited tissue and the excitation time of the radio frequency pulse is not an integer, the number of radio frequency pulses can be the integer part of the quotient value plus 1. That is, it is ensured that after multiple radio frequency pulses corresponding to the number of radio frequency pulses are applied in sequence, the magnetization vector of the excited tissue within the excitation range corresponding to the first applied radio frequency pulse has sufficient recovery time so that the excited tissue can be in the optimal tissue state when it is excited again, thereby achieving more accurate positioning.

[0071] Step 506: Determine the radio frequency pulse sequence based on the frequency range and the number of radio frequency pulses.

[0072] For example, once the frequency range and the required number of radio frequency pulses are determined, different combinations of frequencies and bandwidths can be selected within that frequency range to obtain multiple radio frequency pulses corresponding to the number of radio frequency pulses, thus obtaining a radio frequency pulse sequence.

[0073] The radio frequency (RF) pulse sequence may include multiple RF pulses arranged sequentially according to their frequency magnitude, and the distance between the excitation ranges of adjacent RF pulses is less than a preset distance threshold; that is, the excitation ranges corresponding to multiple RF pulses are closely adjacent or have small intervals, which can basically delineate the dipole field distribution range of the magnet. It should be noted that the frequencies of the multiple RF pulses in the RF pulse sequence are different, but the bandwidths of each RF pulse can be the same or at least partially different. For example, the bandwidths of multiple RF pulses can all be the same, or at least two of the multiple RF pulses can have different bandwidths, or each RF pulse can have a different bandwidth.

[0074] For example, when the magnetic field distribution of a magnet is spherical, the frequency change is more drastic closer to the magnet, resulting in a greater frequency shift. If the frequency range is divided equally, it means that the tissue region corresponding to the frequency range closer to the magnet is smaller than the tissue region corresponding to the frequency range farther from the magnet. Therefore, under equal division, there will be intensity differences between signals. If the magnet is strong, this difference may be even greater, which is not conducive to localization. Therefore, for different radio frequency pulses, different bandwidths can be set as needed. For example, the frequency range (i.e., bandwidth) of several radio frequency pulses closer to the magnet can be set larger, while the frequency range of several radio frequency pulses farther from the magnet can be set smaller, thereby reducing the range difference between the tissue regions corresponding to each radio frequency pulse.

[0075] The following is a specific example for explanation. For instance, taking a magnetic bead robot with a dipole field distribution as an example, with a corresponding frequency range of 0-10000Hz and 3 RF pulses, the three possible combinations of frequency offsets and bandwidths are: the first group f1 = 8000Hz, BW1 = 4000Hz; the second group f2 = 4000Hz, BW2 = 4000Hz; and the third group f3 = 1000Hz, BW3 = 2000Hz. That is, the excitation range corresponding to RF pulse A (f1, BW1) is 6000Hz-10000Hz, the excitation range corresponding to RF pulse B (f2, BW2) is 2000Hz-6000Hz, and the excitation range corresponding to RF pulse C (f3, BW3) is 0Hz-2000Hz. In the first combination of frequency offset and bandwidth and the second combination of frequency offset and bandwidth, the bandwidth of the radio frequency pulse is the same, that is, the bandwidth of radio frequency pulse A and radio frequency pulse B is 4000Hz. However, the bandwidth of radio frequency pulse C formed by the third combination of frequency offset and bandwidth is different from the bandwidth of radio frequency pulse A in the first group and radio frequency pulse B in the second group, and the bandwidth of radio frequency pulse C is smaller than the bandwidth of radio frequency pulse A and radio frequency pulse B.

[0076] It should be noted that the above three combinations of frequency offset and bandwidth are only used as examples. In the case of a frequency range of 0-10000Hz and a number of RF pulses of 3, other combinations of 3 RF pulses with different frequencies and bandwidths can also be selected. This example does not exhaustively list them all.

[0077] Based on the above example, a three-step cycle is used. During each positioning scan, the target radio frequency pulse corresponding to the current positioning scan is determined from the radio frequency pulse sequence according to the preset radio frequency pulse order. This can reduce the original sequence scanning time to 1 / 3, that is, increase the refresh rate by 3 times, while ensuring the strength of the positioning signal and the positioning accuracy.

[0078] In this embodiment, for different magnetic robots, multiple radio frequency pulses with different frequencies and bandwidths can be determined based on the magnetic properties of the magnet, the recovery time of the magnetization vector of the excited tissue, and the excitation time of the radio frequency pulse, forming a radio frequency pulse sequence in the magnetic robot positioning process. Using this radio frequency pulse sequence, the excitation of a specific area can be achieved for the dipole field distribution area of ​​the magnetic robot, avoiding signal saturation. At the same time, the positioning scanning time can be reduced without affecting signal recovery, greatly improving the refresh rate and accuracy of magnetic navigation.

[0079] In one exemplary embodiment, a complete localization method for a magnetic robot is provided, comprising the following steps:

[0080] Step 1: Determine the frequency range based on the magnetic properties of the magnet, and determine the number of radio frequency pulses based on the recovery time of the magnetization vector of the excited tissue and the excitation time of the radio frequency pulse; then, determine the radio frequency pulse sequence based on the frequency range and the number of radio frequency pulses.

[0081] The radio frequency pulse sequence includes multiple radio frequency pulses, and the excitation range of the magnetic field region generated by each radio frequency pulse on the magnet is different; optionally, the radio frequency pulse sequence includes multiple radio frequency pulses arranged in order of frequency magnitude, and the distance between the excitation ranges of adjacent radio frequency pulses is less than a preset distance threshold.

[0082] Step 2: When the robot's end effector is inside the target object, determine the target radio frequency pulse corresponding to the current positioning scan from the preset radio frequency pulse sequence according to the preset radio frequency pulse order.

[0083] Step 3: Control the imaging device to apply a target radio frequency pulse to the target object and acquire the projection signal.

[0084] Step 4: Position the robot's end effector based on the projection signal.

[0085] By using the positioning method provided in this embodiment, the frequency and bandwidth of the radio frequency pulses in each positioning scan can be adjusted to alleviate the signal saturation of previously excited tissues. This not only ensures signal strength and improves positioning accuracy, but also increases the positioning refresh rate.

[0086] It should be understood that although the steps in the flowcharts of the embodiments described above are shown sequentially according to the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless explicitly stated herein, there is no strict order restriction on the execution of these steps, and they can be executed in other orders. Moreover, at least some steps in the flowcharts of the embodiments described above may include multiple steps or multiple stages. These steps or stages are not necessarily completed at the same time, but can be executed at different times. The execution order of these steps or stages is not necessarily sequential, but can be performed alternately or in turn with other steps or at least some of the steps or stages of other steps.

[0087] Based on the same inventive concept, this application also provides a robot positioning device for implementing the robot positioning method described above. The solution provided by this device is similar to the implementation described in the above method; therefore, the specific limitations in one or more robot positioning device embodiments provided below can be found in the limitations of the robot positioning method described above, and will not be repeated here.

[0088] In one exemplary embodiment, such as Figure 6 As shown, a robot positioning device is provided, wherein a magnet is provided at the end of the robot. The device includes: a determining module 602, a control module 604, and a positioning module 606, wherein:

[0089] The determination module 602 is used to determine the target radio frequency pulse corresponding to the current positioning scan from a preset radio frequency pulse sequence when the end of the robot is located inside the target object; the radio frequency pulse sequence includes multiple radio frequency pulses, and the excitation range of the magnetic field region generated by each radio frequency pulse to the magnet is different; the target radio frequency pulse corresponding to the current positioning scan is at least different from the radio frequency pulse corresponding to the previous positioning scan.

[0090] The control module 604 is used to control the imaging device to apply target radio frequency pulses to the target object and to acquire projection signals.

[0091] The positioning module 606 is used to position the end effector of the robot based on the projection signal.

[0092] In one embodiment, the determining module 602 is specifically used to determine the target radio frequency pulse corresponding to the current positioning scan from a preset radio frequency pulse sequence according to a preset radio frequency pulse order.

[0093] In one embodiment, the preset radio frequency pulse sequence is arranged in descending or ascending order of frequency.

[0094] In one embodiment, the device further includes an acquisition module for acquiring a radio frequency pulse sequence; wherein the acquisition module includes:

[0095] The first determining unit is used to determine the frequency range based on the magnetic properties of the magnet;

[0096] The second determining unit is used to determine the number of radio frequency pulses based on the recovery time of the magnetization vector of the excited tissue and the excitation time of the radio frequency pulse;

[0097] The third determining unit is used to determine the radio frequency pulse sequence based on the frequency range and the number of radio frequency pulses.

[0098] In one embodiment, the radio frequency pulse sequence includes multiple radio frequency pulses arranged sequentially according to their frequency magnitude, and the distance between the excitation ranges of adjacent radio frequency pulses is less than a preset distance threshold.

[0099] In one embodiment, the bandwidths of the radio frequency pulses in the radio frequency pulse sequence are the same or at least partially different.

[0100] Each module in the aforementioned robot positioning device can be implemented entirely or partially through software, hardware, or a combination thereof. These modules can be embedded in or independent of the processor in a computer device, or stored in the memory of a computer device as software, so that the processor can call and execute the operations corresponding to each module.

[0101] In one exemplary embodiment, a robot is provided, the end of which is provided with a magnet, and its internal structure can be shown as follows: Figure 7 As shown, the robot includes a processor, memory, input / output interfaces, and a communication interface. The processor, memory, and input / output interfaces are connected via a system bus, and the communication interface is also connected to the system bus via the input / output interfaces. The robot's processor provides computational and control capabilities. The robot's memory includes non-volatile storage media and internal memory. The non-volatile storage media stores the operating system and computer programs. The internal memory provides an environment for the operation of the operating system and computer programs stored in the non-volatile storage media. The robot's input / output interfaces are used for exchanging information between the processor and external devices. The robot's communication interface is used for wired or wireless communication with external terminals; wireless communication can be achieved through Wi-Fi, mobile cellular networks, Near Field Communication (NFC), or other technologies. When the computer program is executed by the processor, it implements a robot localization method.

[0102] Those skilled in the art will understand that Figure 7The structure shown is merely a block diagram of a portion of the structure related to the present application and does not constitute a limitation on the robot to which the present application is applied. A specific robot may include more or fewer parts than shown in the figure, or combine certain parts, or have different part arrangements.

[0103] In one exemplary embodiment, a robot is provided, including a memory and a processor. The robot's end effector is provided with a magnet. The memory stores a computer program, and the processor executes the computer program to perform the following steps:

[0104] When the robot's end effector is located inside the target object, the target radio frequency pulse corresponding to the current positioning scan is determined from a preset radio frequency pulse sequence; the radio frequency pulse sequence includes multiple radio frequency pulses, and each radio frequency pulse generates a different excitation range of the magnetic field region of the magnet; the target radio frequency pulse corresponding to the current positioning scan is at least different from the radio frequency pulse corresponding to the previous positioning scan;

[0105] The imaging device is controlled to apply a target radio frequency pulse to the target object and to acquire the projection signal;

[0106] Positioning of the robot's end effector is based on projection signals.

[0107] In one embodiment, the processor, when executing a computer program, also performs the following steps:

[0108] According to the preset radio frequency pulse sequence, the target radio frequency pulse corresponding to the current positioning scan is determined from the preset radio frequency pulse sequence.

[0109] In one embodiment, the preset radio frequency pulse sequence is arranged in descending order of frequency or ascending order of frequency.

[0110] In one embodiment, the processor, when executing a computer program, also performs the following steps:

[0111] The frequency range is determined based on the magnetic properties of the magnet;

[0112] The number of radio frequency pulses is determined based on the recovery time of the magnetization vector of the excited tissue and the excitation time of the radio frequency pulse.

[0113] The radio frequency pulse sequence is determined based on the frequency range and the number of radio frequency pulses.

[0114] In one embodiment, the radio frequency pulse sequence includes multiple radio frequency pulses arranged sequentially according to their frequency magnitude, and the distance between the excitation ranges of adjacent radio frequency pulses is less than a preset distance threshold.

[0115] In one embodiment, the bandwidths of the radio frequency pulses in the radio frequency pulse sequence are the same or at least partially different.

[0116] In one embodiment, a computer-readable storage medium is provided having a computer program stored thereon, the computer program performing the following steps when executed by a processor:

[0117] When the robot's end effector is located inside the target object, the target radio frequency pulse corresponding to the current positioning scan is determined from a preset radio frequency pulse sequence; the radio frequency pulse sequence includes multiple radio frequency pulses, and each radio frequency pulse generates a different excitation range of the magnetic field region of the magnet; the target radio frequency pulse corresponding to the current positioning scan is at least different from the radio frequency pulse corresponding to the previous positioning scan;

[0118] The imaging device is controlled to apply a target radio frequency pulse to the target object and to acquire the projection signal;

[0119] Positioning of the robot's end effector is based on projection signals.

[0120] In one embodiment, when the computer program is executed by a processor, it also performs the following steps:

[0121] According to the preset radio frequency pulse sequence, the target radio frequency pulse corresponding to the current positioning scan is determined from the preset radio frequency pulse sequence.

[0122] In one embodiment, the preset radio frequency pulse sequence is arranged in descending order of frequency or ascending order of frequency.

[0123] In one embodiment, when the computer program is executed by a processor, it also performs the following steps:

[0124] The frequency range is determined based on the magnetic properties of the magnet;

[0125] The number of radio frequency pulses is determined based on the recovery time of the magnetization vector of the excited tissue and the excitation time of the radio frequency pulse.

[0126] The radio frequency pulse sequence is determined based on the frequency range and the number of radio frequency pulses.

[0127] In one embodiment, the radio frequency pulse sequence includes multiple radio frequency pulses arranged sequentially according to their frequency magnitude, and the distance between the excitation ranges of adjacent radio frequency pulses is less than a preset distance threshold.

[0128] In one embodiment, the bandwidths of the radio frequency pulses in the radio frequency pulse sequence are the same or at least partially different.

[0129] In one embodiment, a computer program product is provided, including a computer program that, when executed by a processor, performs the following steps:

[0130] When the robot's end effector is located inside the target object, the target radio frequency pulse corresponding to the current positioning scan is determined from a preset radio frequency pulse sequence; the radio frequency pulse sequence includes multiple radio frequency pulses, and each radio frequency pulse generates a different excitation range of the magnetic field region of the magnet; the target radio frequency pulse corresponding to the current positioning scan is at least different from the radio frequency pulse corresponding to the previous positioning scan;

[0131] The imaging device is controlled to apply a target radio frequency pulse to the target object and to acquire the projection signal;

[0132] Positioning of the robot's end effector is based on projection signals.

[0133] In one embodiment, when the computer program is executed by a processor, it also performs the following steps:

[0134] According to the preset radio frequency pulse sequence, the target radio frequency pulse corresponding to the current positioning scan is determined from the preset radio frequency pulse sequence.

[0135] In one embodiment, the preset radio frequency pulse sequence is arranged in descending order of frequency or ascending order of frequency.

[0136] In one embodiment, when the computer program is executed by a processor, it also performs the following steps:

[0137] The frequency range is determined based on the magnetic properties of the magnet;

[0138] The number of radio frequency pulses is determined based on the recovery time of the magnetization vector of the excited tissue and the excitation time of the radio frequency pulse.

[0139] The radio frequency pulse sequence is determined based on the frequency range and the number of radio frequency pulses.

[0140] In one embodiment, the radio frequency pulse sequence includes multiple radio frequency pulses arranged sequentially according to their frequency magnitude, and the distance between the excitation ranges of adjacent radio frequency pulses is less than a preset distance threshold.

[0141] In one embodiment, the bandwidths of the radio frequency pulses in the radio frequency pulse sequence are the same or at least partially different.

[0142] It should be noted that the data involved in this application (including but not limited to data used for analysis, data stored, data displayed, etc.) are all information and data that have been fully authorized by all parties, and the collection, use and processing of the relevant data must comply with relevant regulations.

[0143] Those skilled in the art will understand that all or part of the processes in the above embodiments can be implemented by a computer program instructing related hardware. The computer program can be stored in a non-volatile computer-readable storage medium. When executed, the computer program can include the processes of the embodiments described above. Any references to memory, databases, or other media used in the embodiments provided in this application can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetic random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. By way of illustration and not limitation, RAM can take many forms, such as Static Random Access Memory (SRAM) or Dynamic Random Access Memory (DRAM). The databases involved in the embodiments provided in this application may include at least one type of relational database and non-relational database. Non-relational databases may include, but are not limited to, blockchain-based distributed databases. The processors involved in the embodiments provided in this application may be general-purpose processors, central processing units, graphics processing units, digital signal processors, programmable logic devices, quantum computing-based data processing logic devices, etc., and are not limited to these.

[0144] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0145] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of this patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this application should be determined by the appended claims.

Claims

1. A robot localization method, characterized in that, The robot's end effector is equipped with a magnet, and the method includes: When the end effector of the robot is located inside the target object, the target radio frequency pulse corresponding to the current positioning scan is determined from a preset radio frequency pulse sequence; the radio frequency pulse sequence includes multiple radio frequency pulses, and each radio frequency pulse has a different excitation range for the magnetic field region generated by the magnet; the target radio frequency pulse corresponding to the current positioning scan is at least different from the radio frequency pulse corresponding to the previous positioning scan; The imaging device is controlled to apply the target radio frequency pulse to the target object and to acquire the projection signal; The robot's end effector is located based on the projection signal.

2. The method according to claim 1, characterized in that, Determining the target radio frequency pulse from the preset radio frequency pulse sequence includes: The target radio frequency pulse is determined from the preset radio frequency pulse sequence according to the preset radio frequency pulse order.

3. The method according to claim 2, characterized in that, The preset radio frequency pulse sequence is arranged in descending order of frequency or ascending order of frequency.

4. The method according to any one of claims 1-3, characterized in that, The methods for obtaining the radio frequency pulse sequence include: The frequency range is determined based on the magnetic properties of the magnet; The number of radio frequency pulses is determined based on the recovery time of the magnetization vector of the excited tissue and the excitation time of the radio frequency pulses. The radio frequency pulse sequence is determined based on the frequency range and the number of radio frequency pulses.

5. The method according to any one of claims 1-3, characterized in that, The radio frequency pulse sequence includes multiple radio frequency pulses arranged sequentially according to their frequency magnitude, and the distance between the excitation ranges of adjacent radio frequency pulses is less than a preset distance threshold.

6. The method according to any one of claims 1-3, characterized in that, The bandwidths of the radio frequency pulses in the radio frequency pulse sequence are the same or at least partially different.

7. A robot positioning device, characterized in that, The robot's end effector is equipped with a magnet, and the device includes: The determination module is used to determine a target radio frequency pulse from a preset radio frequency pulse sequence when the end effector of the robot is located inside the target object; the radio frequency pulse sequence includes multiple radio frequency pulses of different frequencies, and the excitation range of the magnetic field region generated by each radio frequency pulse is different. The control module is used to control the imaging device to apply the target radio frequency pulse to the target object and to acquire the projection signal; A positioning module is used to locate the end effector of the robot based on the projection signal.

8. A robot comprising a memory and a processor, wherein a magnet is disposed at the end of the robot, and the memory stores a computer program, characterized in that, When the processor executes the computer program, it implements the steps of the method according to any one of claims 1 to 6.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by a processor, it implements the steps of the method according to any one of claims 1 to 6.

10. A computer program product, comprising a computer program, characterized in that, When the computer program is executed by a processor, it implements the steps of the method according to any one of claims 1 to 6.

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