Robot positioning control method and device based on segmented targeted correction

Abstract

The invention provides a robot positioning control method and device based on segmented targeted correction, and relates to the technical field of minimally invasive surgery robots. The method comprises the following steps: planning a puncture path according to the position of a puncture target spot in an image; the robot carries a puncture needle to execute puncture based on the planned puncture path; the puncture angle error of the puncture needle is detected; and correcting the puncture angle error in response to the position of the needle point parking point of the puncture needle. Wherein the critical parking error is defined, and when the detected puncture angle error is larger than the critical parking error, the timer starts to work and records the puncture error duration time; furthermore, critical parking time is defined as a critical time threshold value for judging whether the robot enters the parking point or not, and when the puncture error duration time is larger than the critical parking time, the position where the needle point of the puncture needle is located is the parking point. According to the invention, error accumulation and puncture angle adjustment times can be reduced to the maximum extent, so that the puncture precision and safety are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of minimally invasive surgical robots, and in particular to a robot positioning control method and device based on segmented targeting correction. Background Art

[0002] The medical image-guided puncture robot uses medical imaging equipment to display the puncture target lesion and puncture needle in real time, and determines the position of the puncture target and puncture needle in the medical image through image recognition algorithms, where the lesion position is used as real-time feedback input, and the puncture needle image and robot kinematic model jointly determine the position of the puncture needle as feedback output. During the puncture process, when the force between the puncture needle and the tissue causes the tissue to be squeezed and the puncture target point to shift, the puncture angle can be adjusted in real time by calculating the puncture error to ensure real-time performance.

[0003] The control strategy of existing imaging-guided puncture robots is to control the angle of the puncture needle during the puncture process to align the squeezed and deviated lesions in real time. However, the deformation of soft tissue during the puncture process will cause the lesions to have small pulse jitters. When adjusting the puncture angle, the rotation of the puncture needle will also squeeze the lesion, causing the lesion to further deviate. For the above reasons, the puncture system controls the puncture needle to frequently adjust the insertion angle, which will cause great harm to the patient and make the puncture safety unable to be guaranteed. Summary of the invention

[0004] In view of the above problems, the purpose of the present invention is to provide a robot positioning control method and device based on segmented targeted correction, which ensures the puncture accuracy by setting a parking point during the puncture process and progressively correcting the error. Specifically, the original continuous puncture angle control is discretized, the puncture parking point is set, the puncture angle error is detected in real time, and the parking event is triggered when the parking condition is met. After correcting the puncture error, the puncture is continued, and the puncture target is accurately hit after several parking points. The present invention can minimize the error accumulation and the number of puncture angle adjustments, and significantly improve the puncture accuracy and safety.

[0005] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0006] On the one hand, a robot positioning control method based on segmented targeting correction is provided, the method comprising the following steps:

[0007] The puncture path is planned according to the position of the puncture target in the image; the robot carries the puncture needle and performs puncture based on the planned puncture path;

[0008] Detecting the puncture angle error of the puncture needle; correcting the puncture angle error in response to the position of the puncture needle tip anchor point;

[0009] Where, the critical parking error θ is defined as pause , when the detected puncture angle error θ error (t) is greater than the critical parking error θ pause When the timer starts to work, the puncture error duration t is recorded. error ;

[0010] And, define the critical parking time t pause , t pause To determine the critical time threshold for the robot to enter the parking point, when the puncture error duration t error Greater than critical parking time t pause When the needle tip is at this time, the position of the puncture needle is defined as the anchor point P i .

[0011] Optionally, planning the puncture path according to the position of the puncture target in the image specifically includes:

[0012] The puncture target point is determined according to the target area in the image, and the center of the target area is selected as the puncture target point P. target , read the pixel coordinates of the puncture target Record the radius of the target area r target ;

[0013] The robot is imaged and calibrated to determine the conversion relationship T1 from the robot coordinate system to the image coordinate system. The puncture target point P is obtained through the image calibration relationship. target The coordinates in the robot coordinate system are

[0014]

[0015] According to the location of the puncture target and the target area radius r target , plan the puncture path and determine the needle entry point P entry , initial needle insertion angle θ0, needle insertion depth Deepth.

[0016] Optionally, the robot carries the puncture needle to perform puncture based on the planned puncture path, specifically including:

[0017] According to the geometric relationship of the puncture mechanism model, the relationship F between the puncture needle posture and the motor shaft state is determined, and the inverse kinematics model solution of the robot equipped with the puncture needle is:

[0018]

[0019] Where DoF is the number of degrees of freedom of the robot, l i For the extension of each axis, the robot controls the extension of each axis according to the solution of the inverse kinematics model and starts to perform puncture.

[0020] Optionally, the detecting of the puncture angle error of the puncture needle specifically includes:

[0021] The target area and the position of the puncture needle are identified and tracked in real time through the image recognition algorithm, and the actual position of the current puncture needle is determined in combination with the robot forward kinematics model; the puncture target angle θ with the needle insertion point as the vertex is calculated in real time target (t) and the puncture needle angle θ needle (t), and calculate the puncture angle error θ in real time error (t):

[0022] θ error (t) = θ target (t)-θ needle (t)

[0023] in,

[0024]

[0025] x target (t) and y target (t) is the position coordinate of the puncture target point at time t, x needle (t) and y needle (t) is the position coordinate of the end of the puncture needle at time t, x entry and entry are the position coordinates of the needle entry point.

[0026] Optionally, the critical parking error θ pause The reference range is:

[0027]

[0028] Among them, r target is the radius of the target area, d(t) is the distance between the center of the target area and the end of the puncture needle, and n and m are multiples of the radius of the target area;

[0029] The critical parking time t pause The reference range is:

[0030]

[0031] Among them, t μ is the reference value of the duration of normal physiological jitter, v entry The needle insertion speed.

[0032] Optionally, the correcting of the puncture angle error in response to the position of the puncture needle tip anchorage point specifically includes:

[0033] When the puncture angle error θ is detected error(t) is greater than the critical parking error θ pause , and the puncture error duration t error Greater than critical parking time t pause When , the parking event is triggered;

[0034] When and only when the puncture needle reaches the parking point, the robot controls the puncture needle to make real-time corrections to the puncture angle error. At this time, the puncture target angle θ target (t) is the feedback control system input, the puncture needle angle θ needle (t) is the output of the feedback control system, which controls the angle of the puncture needle. After the puncture needle is aligned with the puncture target again, the robot continues to perform the puncture operation.

[0035] Optionally, the method further comprises:

[0036] The distance between the puncture target and the puncture needle tip is calculated in real time through image detection:

[0037]

[0038] When d(t) is less than the allowable error range, it is considered that the puncture needle has reached the puncture target point, otherwise the parking point position continues to be detected and the puncture angle error is corrected until the puncture needle reaches the puncture target point.

[0039] On the other hand, a robot positioning control device based on segmented targeting correction is provided, which is used to implement any of the above methods, and the device includes:

[0040] The puncture path planning module is used to plan the puncture path according to the position of the puncture target in the image, so that the robot carries the puncture needle to perform puncture based on the planned puncture path;

[0041] A puncture angle error detection module is used to detect the puncture angle error of the puncture needle;

[0042] A control module, for correcting the puncture angle error in response to the position of the puncture needle tip anchorage point;

[0043] Where, the critical parking error θ is defined as pause , when the detected puncture angle error θ error (t) is greater than the critical parking error θ pause When the timer starts to work, the puncture error duration t is recorded. error ;

[0044] And, define the critical parking time t pause , t pause To determine the critical time threshold for the robot to enter the parking point, when the puncture error duration t error Greater than critical parking time t pauseWhen the needle tip is at this time, the position of the puncture needle is defined as the anchor point P i .

[0045] Optionally, the puncture path planning module is specifically used for:

[0046] The puncture target point is determined according to the target area in the image, and the center of the target area is selected as the puncture target point P. target , read the pixel coordinates of the puncture target Record the radius of the target area r target ;

[0047] The robot is imaged and calibrated to determine the conversion relationship T1 from the robot coordinate system to the image coordinate system. The puncture target point P is obtained through the image calibration relationship. target The coordinates in the robot coordinate system are

[0048]

[0049] According to the location of the puncture target and the target area radius r target , plan the puncture path and determine the needle entry point P entry , initial needle insertion angle θ0, needle insertion depth Deepth.

[0050] Optionally, the robot carries the puncture needle to perform puncture based on the planned puncture path, specifically including:

[0051] According to the geometric relationship of the puncture mechanism model, the relationship F between the puncture needle posture and the motor shaft state is determined, and the inverse kinematics model solution of the robot equipped with the puncture needle is:

[0052]

[0053] Where DoF is the number of degrees of freedom of the robot, l i For the extension of each axis, the robot controls the extension of each axis according to the solution of the inverse kinematics model and starts to perform puncture.

[0054] Optionally, the puncture angle error detection module is specifically used for:

[0055] The target area and the position of the puncture needle are identified and tracked in real time through the image recognition algorithm, and the actual position of the current puncture needle is determined in combination with the robot forward kinematics model; the puncture target angle θ with the needle insertion point as the vertex is calculated in real time target (t) and the puncture needle angle θ needle (t), and calculate the puncture angle error θ in real time error (t):

[0056] θ error (t) = θtarget (t)-θ needle (t)

[0057] in,

[0058]

[0059] x target (t) and y target (t) is the position coordinate of the puncture target point at time t, x needle (t) and y needle (t) is the position coordinate of the end of the puncture needle at time t, x entry and entry are the position coordinates of the needle entry point.

[0060] Optionally, the critical parking error θ pause The reference range is:

[0061]

[0062] Among them, r target is the radius of the target area, d(t) is the distance between the center of the target area and the end of the puncture needle, and n and m are multiples of the radius of the target area;

[0063] The critical parking time t pause The reference range is:

[0064]

[0065] Among them, t μ is the reference value of the duration of normal physiological jitter, v entry The needle insertion speed.

[0066] Optionally, the control module is specifically used to:

[0067] When the puncture angle error θ is detected error (t) is greater than the critical parking error θ pause , and the puncture error duration t error Greater than critical parking time t pause When , the parking event is triggered;

[0068] When and only when the puncture needle reaches the parking point, the robot controls the puncture needle to make real-time corrections to the puncture angle error. At this time, the puncture target angle θ target (t) is the feedback control system input, the puncture needle angle θ needle (t) is the output of the feedback control system, which controls the angle of the puncture needle. After the puncture needle is aligned with the puncture target again, the robot continues to perform the puncture operation.

[0069] Optionally, the device further comprises:

[0070] The distance detection module is used to calculate the distance between the puncture target and the puncture needle tip in real time through image detection:

[0071]

[0072] When d(t) is less than the allowable error range, it is considered that the puncture needle has reached the puncture target point, otherwise the parking point position continues to be detected and the puncture angle error is corrected until the puncture needle reaches the puncture target point.

[0073] In another aspect, an electronic device is provided, the electronic device comprising:

[0074] processor;

[0075] A memory having computer-readable instructions stored thereon, wherein when the computer-readable instructions are loaded and executed by the processor, the steps of the robot positioning control method as described above are implemented.

[0076] On the other hand, a computer-readable storage medium is provided, in which a program code is stored. The program code can be called by a processor to execute the steps of the robot positioning control method as described above.

[0077] The beneficial effects brought about by the technical solution provided by the present invention include at least:

[0078] The image-guided robot positioning control method based on segmented targeted correction provided by the present invention detects puncture errors in real time, and processes puncture errors in a discrete manner by setting a parking point, which greatly reduces the number of times the puncture needle angle is adjusted, and can improve the safety of puncture. At the parking point, the method compensates for the puncture angle error through feedback control, which can effectively reduce the accumulation of errors and greatly improve the accuracy of puncture. BRIEF DESCRIPTION OF THE DRAWINGS

[0079] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0080] Figure 1 is a flow chart of a robot positioning control method based on segmented targeting correction provided by an embodiment of the present invention;

[0081] Figure 2 is a schematic diagram of the kinematic model of the puncture robot provided by an embodiment of the present invention;

[0082] Figure 3is a flow chart of an image recognition algorithm provided by an embodiment of the present invention;

[0083] Figure 4 It is a puncture angle error correction feedback control block diagram provided by an embodiment of the present invention;

[0084] Figure 5 is a schematic diagram of angle adjustment during puncture provided by an embodiment of the present invention;

[0085] Figure 6 It is a schematic diagram of the relationship between the angle between the target and the puncture needle during the puncture process provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0086] In order to make the purpose, technical solution and advantages of the embodiment of the present invention clearer, the technical solution of the embodiment of the present invention will be clearly and completely described below in conjunction with the drawings of the embodiment of the present invention. Obviously, the described embodiment is a part of the embodiment of the present invention, not all of the embodiments. Based on the described embodiment of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0087] In the embodiments of the present invention, words such as "exemplarily" and "for example" are used to indicate examples, illustrations or explanations. Any embodiment or design described as "exemplary" in the present invention should not be interpreted as being more preferred or more advantageous than other embodiments or designs. Specifically, the word "exemplary" is used to present concepts in a specific way.

[0088] The embodiment of the present invention provides a robot positioning control method based on segmented targeting correction, which can be implemented by an electronic device, which can be a terminal or a server. Figure 1 As shown, the processing flow of the method may include the following steps:

[0089] S1. Perform medical imaging scan on the soft tissue simulation body, determine the target area, and select the center of the target area as the puncture target point.

[0090] In the embodiment of the present invention, a soft tissue simulation body is used as a puncture object, and a target area is set therein to simulate a real lesion. The soft tissue simulation body is a phantom prepared by imitating patient tissue.

[0091] In this step, the target region ROI (region of interest) is determined according to the medical image of the soft tissue simulation body, and the center of the target region is selected as the puncture target point P target , read the pixel coordinates of the puncture target Record the radius of the target area r target .

[0092] S2. According to the position of the puncture target in the image, the actual position is obtained through the image calibration relationship, the puncture path is planned, and the puncture needle point P is determined. entry , initial needle insertion angle θ0 and needle insertion depth Deepth.

[0093] In this step, the robot is first calibrated by imaging to determine the transformation relationship T1 from the robot coordinate system to the imaging coordinate system. The puncture target point P is obtained through the imaging calibration relationship. target Coordinates in the robot coordinate system

[0094]

[0095] According to the location of the puncture target and the target area radius r target , plan the puncture path and determine the needle entry point P entry , initial needle insertion angle θ0, needle insertion depth Deepth.

[0096] S3. Based on the planned puncture path and the inverse kinematics model of the robot, the extension of each axis of the robot is determined, and the puncture is started.

[0097] In this step, the relationship F between the puncture needle posture and the motor shaft state is determined according to the geometric relationship of the puncture mechanism model, and the inverse kinematics model solution of the robot carrying the puncture needle is:

[0098]

[0099] Where DoF is the number of degrees of freedom of the robot, l i For the extension of each axis, the robot controls the extension of each axis according to the solution of the inverse kinematics model and starts to perform puncture.

[0100] Specifically, the kinematic model of the puncture robot is as follows: Figure 2 As shown in (a) and (b), the relationship between the puncture needle posture and the motor shaft state can be determined based on the geometric relationship of the puncture mechanism model, and then the inverse kinematics model solution of the puncture robot can be obtained:

[0101]

[0102] Wherein l1, l2 and l3 are the elongations of the axes of the puncture robot, h, d and L0 are the structural parameters of the puncture robot in this embodiment, and the robot starts puncturing by controlling the elongation of each axis according to the inverse kinematics model solution.

[0103] S4. The puncture process is tracked in real time through image recognition algorithm, and the actual position of the current puncture needle is determined in combination with the robot forward kinematics model, and the puncture angle error is calculated in real time.

[0104] In this embodiment, in order to increase the accuracy of the recognition result, a method combining Hough detection and Kalman filtering is used to identify the target. The algorithm flow is as follows: Figure 3 As shown, specifically, it includes: performing Gaussian smoothing filtering on the medical image frame by frame to minimize the influence of irrelevant noise on image recognition, and performing Hough detection on a frame by frame basis in the selected ROI area to identify the target area and the real-time position of the puncture needle.

[0105] Based on the Kalman filter, the image recognition results are optimized in real time, and the targets detected in the previous frames are used as prior knowledge. For the puncture needle, the Kalman prediction of the puncture needle position is performed according to the puncture needle posture solved by the forward kinematics model of the puncture robot and the puncture needle insertion speed. If the detection target of the current frame is lost or jumps, the prediction result is used as the detection target of the current frame.

[0106] In the embodiment of the present invention, the forward kinematics model solution of the puncture robot is:

[0107]

[0108] Add custom restrictions to further improve detection accuracy and stability, including:

[0109] Define the displacement critical pixel S. If the distance between the detection result of the current frame and the previous frame exceeds S, take the distance S along the change direction as the detection result of the current frame; define the critical number of lost frames N l , if N consecutive l If the target is not detected in a frame, it is considered that the target has temporarily disappeared, the Kalman prediction is stopped, and the target loss in the previous frame is cancelled as the detection result until the target is detected again;

[0110] Add a low-pass filter to filter the high-frequency noise in the detected results to further improve the stability of the detection results. According to the above image recognition algorithm, the puncture target point P can be obtained in real time. target (t) and the end of the puncture needle P needle The position of (t).

[0111] Furthermore, the puncture angle error θ can be calculated in real time error (t):

[0112] θ error (t) = θ target (t)-θ needle (t)

[0113] in:

[0114]

[0115] x target (t) and ytarget (t) is the position coordinate of the puncture target point at time t, x needle (t) and y needle (t) is the position coordinate of the end of the puncture needle at time t, x entry and entry are the position coordinates of the needle entry point.

[0116] S5. Define a parking point. When and only when the puncture needle reaches the parking point, the robot controls the puncture needle to make real-time corrections to the puncture angle error.

[0117] In this step, define the anchor point P i , P i The point where the puncture needle tip is located when the robot pauses the needle insertion operation and starts the puncture angle error correction during the puncture process. When and only when the puncture needle reaches the parking point, the robot controls the puncture needle to correct the puncture angle error in real time until the puncture angle error is 0.

[0118] Define the critical parking error θ pause ,θ pause is the critical error threshold for the system to start detecting the error duration. When the puncture angle error θ of the puncture needle is detected error (t) is greater than the critical parking error θ pause When the timer starts to work, the puncture error duration t is recorded. error , preferably, if and only if the puncture angle error θ error (t) is greater than the critical parking error θ pause When the timer starts to work, the puncture error duration t is recorded. error .

[0119] Define critical parking time t pause , t pause To determine the critical time threshold for the robot to enter the parking point, when the puncture error duration t error Greater than critical parking time t pause Preferably, if and only if the puncture error duration t error Greater than critical parking time t pause When , the timer is cleared and the parking event is triggered. At this time, the position of the puncture needle tip is the parking point P i .

[0120] In the embodiment of the present invention, it is necessary to determine the critical parking error θ pause and critical parking time t pause The size is limited.

[0121] If the critical parking error θ pauseIf the setting is too small, there will be too many parking points. If the setting is too large, the puncture needle will not be able to complete the angle adjustment. target The critical parking error is reasonably selected based on the ratio of the distance between the center of the target area (puncture target point) and the tip of the puncture needle. For example, the present invention uses the puncture angle error when the puncture needle deviates from n times the radius of the target area but does not exceed m times the radius of the target area as the range of the critical parking error. Preferably, the typical value of n is 1, and the typical value of m is 1.5. Assuming that the distance between the target area and the end (tip) of the puncture needle is d(t), the critical parking error θ pause The reference range is:

[0122]

[0123] Among them, r target is the radius of the target area, and d(t) is the distance between the center of the target area and the end of the puncture needle.

[0124] If the critical parking time t pause If the setting is too small, the robot will be greatly affected by physiological shaking such as tremor. If the setting is too large, the puncture angle error will continue to increase, making correction difficult. The critical parking time of the present invention is set to be greater than the duration of conventional physiological shaking t μ (The reference value is about 0.4 to 0.6 s) and is less than the time required for the end of the puncture needle to move the radius of the target area. Let the needle speed be v entry , then the critical parking time t pause The reference range is:

[0125]

[0126] Among them, v entry The needle insertion speed.

[0127] When the puncture angle error θ is detected error (t) is greater than the critical parking error θ pause , and the puncture error duration t error Greater than critical parking time t pause , triggers the parking event.

[0128] When and only when the robot is at the parking point, the system controls the robot to correct the puncture angle error in real time. At this time, the puncture target angle θ target (t) is the feedback control system input, the puncture needle angle θ needle (t) is the output of the feedback control system. In this embodiment of the invention, the PID control method is used to adjust the angle of the puncture needle at the parking point. After the puncture needle is aligned with the puncture target again, the robot continues to perform the puncture operation.

[0129] Specifically, the puncture angle error correction feedback control block diagram is as follows: Figure 4 As shown in the figure, the puncture angle error θ error (t) Input into PID controller to get the angle adjustment:

[0130]

[0131] Among them, τ is the working time of the current control system, K p is the proportional coefficient of the PID controller, K i is the integral coefficient of the PID controller, K d is the differential coefficient of the PID controller.

[0132] like Figure 5 As shown, according to the angle adjustment amount θ adjust (t) can determine the correction amount of each axis of the robot at the next moment:

[0133]

[0134] Then, the expected position of the end of the puncture needle after the robot axes are corrected is calculated according to the robot forward kinematics model as the Kalman prediction value, and the puncture needle end P at that moment is determined in combination with the puncture needle image recognition result. tip Actual location Finally, the current puncture needle angle θ is calculated needle (t) is used as the control system output.

[0135] When the puncture angle error θ error After (t) is corrected, the robot controls the puncture needle to continue puncturing.

[0136] S6. Determine whether the puncture needle has reached the puncture target point based on image detection. If not, re-execute S4 and S5 until the puncture needle hits the puncture target point.

[0137] In this step, the distance between the target area and the end of the puncture needle is calculated in real time through image detection:

[0138]

[0139] When d(t) is less than the allowable error range, it is considered that the puncture needle has reached the puncture target point. Otherwise, S4 and S5 are re-executed to continue to detect and correct the puncture angle error, passing through several parking points until the puncture needle hits the puncture target point. In this embodiment, the relationship between the puncture process target and the angle of the puncture needle over time is as follows: Figure 6 shown.

[0140] Compared with the traditional medical image-guided puncture feedback control method, the present invention provides an image-guided robot positioning control method based on segmented targeted correction. The method detects puncture errors in real time and processes puncture errors in a discrete manner by setting a parking point, which greatly reduces the number of puncture needle angle adjustments and can improve the safety of puncture. In addition, the method compensates for the puncture angle error through feedback control at the parking point, which can effectively reduce the accumulation of errors and greatly improve the accuracy of puncture.

[0141] Accordingly, an embodiment of the present invention further provides a robot positioning control device based on segmented targeting correction, the device comprising:

[0142] The puncture path planning module is used to plan the puncture path according to the position of the puncture target in the image, so that the robot carries the puncture needle to perform puncture based on the planned puncture path;

[0143] A puncture angle error detection module is used to detect the puncture angle error of the puncture needle;

[0144] A control module, for correcting the puncture angle error in response to the position of the puncture needle tip anchorage point;

[0145] Where, the critical parking error θ is defined as pause , when the detected puncture angle error θ error (t) is greater than the critical parking error θ pause When the timer starts to work, the puncture error duration t is recorded. error ;

[0146] And, define the critical parking time t pause , t pause To determine the critical time threshold for the robot to enter the parking point, when the puncture error duration t error Greater than critical parking time t pause When the needle tip is at this time, the position of the puncture needle is defined as the anchor point P i .

[0147] Furthermore, the puncture path planning module is specifically used for:

[0148] The puncture target point is determined according to the target area in the image, and the center of the target area is selected as the puncture target point P. target , read the pixel coordinates of the puncture target Record the radius of the target area r target ;

[0149] The robot is imaged and calibrated to determine the conversion relationship T1 from the robot coordinate system to the image coordinate system. The puncture target point P is obtained through the image calibration relationship. targetThe coordinates in the robot coordinate system are

[0150]

[0151] According to the location of the puncture target and the target area radius r target , plan the puncture path and determine the needle entry point P entry , initial needle insertion angle θ0, needle insertion depth Deepth.

[0152] Furthermore, the robot carries the puncture needle to perform puncture based on the planned puncture path, specifically including:

[0153] According to the geometric relationship of the puncture mechanism model, the relationship F between the puncture needle posture and the motor shaft state is determined, and the inverse kinematics model solution of the robot equipped with the puncture needle is:

[0154]

[0155] Where DoF is the number of degrees of freedom of the robot, l i For the extension of each axis, the robot controls the extension of each axis according to the solution of the inverse kinematics model and starts to perform puncture.

[0156] Furthermore, the puncture angle error detection module is specifically used for:

[0157] The target area and the position of the puncture needle are identified and tracked in real time through the image recognition algorithm, and the actual position of the current puncture needle is determined in combination with the robot forward kinematics model; the puncture target angle θ with the needle insertion point as the vertex is calculated in real time target (t) and the puncture needle angle θ needle (t), and calculate the puncture angle error θ in real time error (t):

[0158] θ error (t) = θ target (t)-θ needle (t)

[0159] in,

[0160]

[0161] x target (t) and y target (t) is the position coordinate of the puncture target point at time t, x needle (t) and y needle (t) is the position coordinate of the end of the puncture needle at time t, x entry and entry are the position coordinates of the needle entry point.

[0162] Furthermore, the critical parking error θ pause The reference range is:

[0163]

[0164] Among them, r target is the radius of the target area, d(t) is the distance between the center of the target area and the end of the puncture needle, and n and m are multiples of the radius of the target area;

[0165] The critical parking time t pause The reference range is:

[0166]

[0167] Among them, t μ is the reference value of the duration of normal physiological jitter, v entry The needle insertion speed.

[0168] Furthermore, the control module is specifically used for:

[0169] When the puncture angle error θ is detected error (t) is greater than the critical parking error θ pause , and the puncture error duration t error Greater than critical parking time t pause When , the parking event is triggered;

[0170] When and only when the puncture needle reaches the parking point, the robot controls the puncture needle to make real-time corrections to the puncture angle error. At this time, the puncture target angle θ target (t) is the feedback control system input, the puncture needle angle θ needle (t) is the output of the feedback control system, which controls the angle of the puncture needle. After the puncture needle is aligned with the puncture target again, the robot continues to perform the puncture operation.

[0171] Furthermore, the device also includes:

[0172] The distance detection module is used to calculate the distance between the puncture target and the puncture needle tip in real time through image detection:

[0173]

[0174] When d(t) is less than the allowable error range, it is considered that the puncture needle has reached the puncture target point, otherwise the parking point position continues to be detected and the puncture angle error is corrected until the puncture needle reaches the puncture target point.

[0175] In an exemplary embodiment, the present invention further provides an electronic device, the electronic device comprising:

[0176] processor;

[0177] A memory having computer-readable instructions stored thereon, wherein when the computer-readable instructions are loaded and executed by the processor, the steps of the robot positioning control method as described above are implemented.

[0178] In an exemplary embodiment, the present invention further provides a computer-readable storage medium, wherein at least one instruction is stored in the computer-readable storage medium, and the at least one instruction is loaded and executed by a processor to implement the steps of the robot positioning control method as described above. For example, the computer-readable storage medium can be a ROM, a random access memory (RAM), a CD-ROM, a magnetic tape, a floppy disk, an optical data storage device, etc.

[0179] It should be noted that, in this article, the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or terminal device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or terminal device. In the absence of further restrictions, the elements defined by the sentence "comprises a ..." do not exclude the existence of other identical elements in the process, method, article or terminal device including the elements.

[0180] References in the specification to "one embodiment", "an embodiment", "an exemplary embodiment", "some embodiments", etc. indicate that the described embodiments may include a particular feature, structure, or characteristic, but not every embodiment may include the particular feature, structure, or characteristic. In addition, when a particular feature, structure, or characteristic is described in conjunction with an embodiment, it should be within the knowledge of a person skilled in the relevant art to implement such feature, structure, or characteristic in conjunction with other embodiments (whether or not explicitly described).

[0181] It should be understood that the term "and / or" in this article is only a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. A and B can be singular or plural. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship, but it may also indicate an "and / or" relationship. Please refer to the context for specific understanding.

[0182] In the present invention, "at least one" means one or more, and "more than one" means two or more. "At least one of the following" or similar expressions refers to any combination of these items, including any combination of single or plural items. For example, at least one of a, b, or c can be represented by: a, b, c, ab, ac, bc, or abc, where a, b, c can be single or multiple.

[0183] It should be understood that in various embodiments of the present invention, the size of the serial numbers of the above-mentioned processes does not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present invention.

[0184] In the several embodiments provided by the present invention, it should be understood that the disclosed devices, apparatuses and methods can be implemented in other ways. For example, the device embodiments described above are only schematic. For example, the division of the units is only a logical function division. There may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another device, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0185] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0186] In addition, each functional unit in each embodiment of the present invention may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit.

[0187] If the functions are implemented in the form of software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention can be essentially or partly embodied in the form of a software product that contributes to the prior art. The computer software product is stored in a storage medium and includes several instructions for enabling a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the methods described in various embodiments of the present invention. The aforementioned storage medium includes: various media that can store program codes, such as a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk.

[0188] The present invention covers any substitution, modification, equivalent method and scheme made on the essence and scope of the present invention. In order to make the public have a thorough understanding of the present invention, specific details are described in detail in the following preferred embodiments of the present invention, but those skilled in the art can fully understand the present invention without the description of these details. In addition, in order to avoid unnecessary confusion about the essence of the present invention, well-known methods, processes, procedures, components and circuits are not described in detail.

[0189] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A robot positioning control method based on segmented targeting correction, characterized in that: The method comprises the following steps: The puncture path is planned according to the position of the puncture target in the image; the robot carries the puncture needle and performs puncture based on the planned puncture path; Detecting the puncture angle error of the puncture needle; and correcting the puncture angle error in response to the position of the puncture needle tip anchoring point; Where, the critical parking error θ is defined as pause , when the detected puncture angle error θ error (t) is greater than the critical parking error θ pause When the timer starts to work, the puncture error duration t is recorded. error ; And, define the critical parking time t pause , t pause To determine the critical time threshold for the robot to enter the parking point, when the puncture error duration t error Greater than critical parking time t pause When the needle tip is at this time, the position of the puncture needle is defined as the anchor point P i .

2. The robot positioning control method based on segmented targeting correction according to claim 1 is characterized in that: The planning of the puncture path according to the position of the puncture target in the image specifically includes: The puncture target point is determined according to the target area in the image, and the center of the target area is selected as the puncture target point P. target , read the pixel coordinates of the puncture target Record the radius of the target area r target ; The robot is imaged and calibrated to determine the conversion relationship T1 from the robot coordinate system to the image coordinate system. The puncture target point P is obtained through the image calibration relationship. target The coordinates in the robot coordinate system are According to the location of the puncture target and the target area radius r target , plan the puncture path and determine the needle entry point P entry , initial needle insertion angle θ0, needle insertion depth Deepth.

3. The robot positioning control method based on segmented targeting correction according to claim 1 is characterized in that: The robot carries the puncture needle to perform puncture based on the planned puncture path, specifically including: According to the geometric relationship of the puncture mechanism model, the relationship F between the puncture needle posture and the motor shaft state is determined, and the inverse kinematics model solution of the robot equipped with the puncture needle is: Where DoF is the number of degrees of freedom of the robot, l i For the extension of each axis, the robot controls the extension of each axis according to the solution of the inverse kinematics model and starts to perform puncture.

4. The robot positioning control method based on segmented targeting correction according to claim 1 is characterized in that: The detection of the puncture angle error of the puncture needle specifically includes: The target area and the position of the puncture needle are identified and tracked in real time through the image recognition algorithm, and the actual position of the current puncture needle is determined in combination with the robot forward kinematics model; the puncture target angle θ with the needle insertion point as the vertex is calculated in real time target (t) and the puncture needle angle θ needle (t), and calculate the puncture angle error θ in real time error (t): i error (t)=θ target (t)-θ needle (t) in, x target (t) and y target (t) is the position coordinate of the puncture target point at time t, x needle (t) and y needle (t) is the position coordinate of the end of the puncture needle at time t, x entry and entry are the position coordinates of the needle entry point.

5. The robot positioning control method based on segmented targeting correction according to claim 1 is characterized in that: The critical parking error θ pause The reference range is: Among them, r target is the radius of the target area, d(t) is the distance between the center of the target area and the end of the puncture needle, and n and m are multiples of the radius of the target area; The critical parking time t pause The reference range is: Among them, t μ is the reference value of the duration of normal physiological jitter, v entry The needle insertion speed.

6. The robot positioning control method based on segmented targeting correction according to claim 1 is characterized in that: The correction of the puncture angle error in response to the position of the puncture needle tip anchorage point specifically includes: When the puncture angle error θ is detected error (t) is greater than the critical parking error θ pause , and the puncture error duration t error Greater than critical parking time t pause When , the parking event is triggered; When and only when the puncture needle reaches the parking point, the robot controls the puncture needle to make real-time corrections to the puncture angle error. At this time, the puncture target angle θ target (t) is the feedback control system input, the puncture needle angle θ needle (t) is the output of the feedback control system, which controls the angle of the puncture needle. After the puncture needle is aligned with the puncture target again, the robot continues to perform the puncture operation.

7. The robot positioning control method based on segmented targeting correction according to claim 1 is characterized in that: The method further comprises: The distance between the puncture target and the puncture needle tip is calculated in real time through image detection: When d(t) is less than the allowable error range, it is considered that the puncture needle has reached the puncture target point, otherwise the parking point position continues to be detected and the puncture angle error is corrected until the puncture needle reaches the puncture target point.

8. A robot positioning control device based on segmented targeting correction, characterized in that: The device comprises: The puncture path planning module is used to plan the puncture path according to the position of the puncture target in the image, so that the robot carries the puncture needle to perform puncture based on the planned puncture path; A puncture angle error detection module is used to detect the puncture angle error of the puncture needle; A control module, for correcting the puncture angle error in response to the position of the puncture needle tip anchorage point; Where, the critical parking error θ is defined as pause , when the detected puncture angle error θ error (t) is greater than the critical parking error θ pause When the timer starts to work, the puncture error duration t is recorded. error ; And, define the critical parking time t pause , t pause To determine the critical time threshold for the robot to enter the parking point, when the puncture error duration t error Greater than critical parking time t pause When the needle tip is at this time, the position of the puncture needle is defined as the anchor point P i .

9. An electronic device, characterized in that: The electronic device comprises: processor; A memory having computer-readable instructions stored thereon, wherein the computer-readable instructions, when loaded and executed by the processor, implement the method according to any one of claims 1 to 8.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores program code, which can be called by a processor to execute the method according to any one of claims 1 to 8.

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