Acupuncture flexible robotic arm and method of use thereof

Abstract

The application discloses a kind of acupuncture flexible mechanical arm and its using method, belong to intelligent medical treatment technical field, acupuncture flexible mechanical arm includes control system and with the wire driving device electrically connected with control system, wire driving device includes installation fixed base disk and multiple wire driving components;Installation fixed base disk is provided with flexible hose, multiple support discs are provided on the outer wall of flexible hose, multiple through holes are provided on each support disc, the execution end of flexible hose is provided with needle and depth camera;Acupuncture flexible mechanical arm realizes the execution end of flexible hose and needle and depth camera on it according to predetermined trajectory movement by using wire driving mode, drives needle to be inserted into human acupoint to achieve the purpose of acupuncture treatment, more safe on man-machine interaction, solve the problem that the safety hidden danger that robot acupuncture system exists and is easily collided with patient body because of using rigid multi-axis mechanical arm to realize driving needle movement.

Description

Technical Field

[0001] This invention belongs to the field of intelligent medical treatment technology, and in particular relates to a flexible acupuncture robotic arm and its usage method. Background Technology

[0002] Acupuncture is a commonly used treatment method guided by Traditional Chinese Medicine (TCM) theory. Acupuncture is a general term encompassing needling and moxibustion techniques. This invention primarily focuses on needling techniques. In traditional Chinese medicine, practitioners select specific acupoints as insertion points and insert needles (usually filiform needles) into the patient's body at a specific angle to achieve therapeutic effects. The most crucial and core technique in acupuncture is the precise location of acupoints.

[0003] A robot is a machine device that automatically performs tasks. With the continuous development of robotics technology, robots are no longer limited to simple repetitive tasks. The development of intelligent robots enables them to perform actions according to pre-set principles and guidelines. The composition of a robot varies depending on the application, but generally includes an actuator, a drive unit, and a control system. The robot uses the control system to control the drive unit, which in turn controls the actuator to move according to the instructions in the control system.

[0004] In existing technologies, there are technical solutions that combine acupuncture with robotics to achieve acupuncture treatment, such as CN220459615U - A Remote Collaborative Robotic Acupuncture System. This robotic acupuncture system includes an acupuncture robot and a remote operation terminal, which are connected via a network. The acupuncture robot includes a multi-axis robotic arm, a monitoring module, and an acupuncture operation group. Both the monitoring module and the acupuncture operation group are mounted on the multi-axis robotic arm. The multi-axis robotic arm operates the acupuncture operation group to move to the acupuncture point on the body. The monitoring module is configured to capture images and monitor in real time. The remote operation terminal includes a teach pendant, a display, and a controller. The teach pendant has the same structure as the multi-axis robotic arm. When the teach pendant is operated in a network connection state, the multi-axis robotic arm moves accordingly. The display is used to display images captured by the monitoring module, and the controller is configured to operate the acupuncture operation group. This solution uses remote control, with the cooperation of the monitoring module, to control the teach pendant, thereby enabling the multi-axis robotic arm to move synchronously.

[0005] However, in existing technologies, rigid multi-axis robotic arms are usually used to move the needle. During human-computer interaction, if the patient moves, the patient's body may collide with the multi-axis robotic arm, causing safety issues and posing a safety hazard. Summary of the Invention

[0006] This invention aims to provide a flexible acupuncture robotic arm and its usage method, solving the safety hazard of collisions with the patient's body that arises from the use of rigid multi-axis robotic arms to move needles in robotic acupuncture systems.

[0007] To achieve the above-mentioned objectives, the technical solution adopted by this invention is as follows:

[0008] A flexible acupuncture robotic arm is provided, which includes a control system and a wire drive device electrically connected to the control system. The wire drive device includes a mounting base and a plurality of wire drive components.

[0009] A flexible tube is provided on the mounting base. Multiple support discs are evenly spaced along the length of the flexible tube on its outer wall. Each support disc has multiple through holes. A needle, a depth camera, and a fiber optic sensor are provided at the end of the flexible tube. The depth camera is electrically connected to the control system. Each wire drive component includes a rotating winding wheel with a drive wire wound on it. The drive wires of the multiple wire drive components pass through the multiple through holes and are fixedly connected to the support discs located at the end of the flexible tube.

[0010] The basic principle of a flexible acupuncture robotic arm is as follows: by setting a support disk on a flexible tube, and using a wire-driven method, the execution end of the flexible tube and the needles, depth camera, and fiber optic sensor on it move according to a predetermined trajectory, driving the needles to insert into acupoints to achieve the purpose of acupuncture treatment; the fiber optic sensor is used to detect the bending angle and bending plane angle of the flexible tube and provide real-time feedback to improve the motion accuracy of the execution end of the flexible tube; due to the setting of the flexible tube, the entire robotic arm is flexible, and even if the robotic arm collides with the patient's body when the patient moves, it will not cause injury to the patient, thus improving the safety of use. Compared with traditional rigid robots, the flexible acupuncture robotic arm of this invention is safer in human-computer interaction.

[0011] Furthermore, in a specific arrangement of the flexible hose and multiple support discs, the flexible hose includes a first arm segment, a second arm segment, and a third arm segment connected to each other; three support discs are evenly spaced along their own length on the outer walls of the first arm segment, the second arm segment, and the third arm segment.

[0012] One end of the first arm segment is fixedly connected to the center of the mounting base plate via a base plate;

[0013] Each supporting disk has a radius of r a Nine vias are evenly arranged circumferentially on each of the pitch circles;

[0014] The number of the wire drive components is 9, with 3 wire drive components matched to each of the first arm segment, the second arm segment, and the third arm segment;

[0015] Three of the three drive lines of the three line drive components that are matched with the first arm segment pass through the through holes on the three support discs and are fixedly connected to the support disc located at the end of the first arm segment; the included angle between the three drive lines that are matched with the first arm segment is 120°;

[0016] Three of the three drive lines of the three line drive components that are matched with the second arm segment pass through the through holes on the six support discs and are fixedly connected to the support disc located at the end of the second arm segment; the included angle between the three drive lines that cooperate with the second arm segment is 120°;

[0017] Three of the three drive lines of the three line drive components that are matched with the third arm segment pass through the through holes on the nine support discs and are fixedly connected to the support disc located at the end of the third arm segment; the included angle between the three drive lines that cooperate with the third arm segment is 120°; the needle and the depth camera are both located at the end of the third arm segment.

[0018] The first, second, and third arm segments are all redundantly driven by three line-driven components, thereby achieving two-degree-of-freedom bending motion at the ends of the first, second, and third arm segments, and ultimately realizing six-degree-of-freedom control of the entire flexible hose's end effector.

[0019] Furthermore, each via is provided with one drive wire. This arrangement avoids the problem of multiple drive wires moving uncomfortably when installed in a single via.

[0020] Furthermore, as a specific arrangement of the wire drive device, the wire drive device also includes a support frame disposed below the mounting base, and the lower end face of the mounting base is fixedly connected to the upper end face of the support frame through multiple support columns.

[0021] Nine motors are installed inside the support frame. The output shaft of each motor passes through the top of the support frame and is connected to a winding wheel. Each winding wheel is located between the support frame and the mounting base. Each winding wheel has a wire-passing hole at its top. The drive wire on each winding wheel passes through the wire-passing hole, the mounting base, and the base plate in sequence and is fixedly connected to the support disc located at the end of the first arm segment, the second arm segment, or the third arm segment.

[0022] In the above technical solution, the motor realizes the rotation of the winding wheel, thereby realizing the winding or unwinding of the drive line on the winding wheel; and the setting of the wire hole is used to guide the drive line, so that the drive line is neatly arranged on the winding wheel during the winding or unwinding process.

[0023] Furthermore, the lower end face of the mounting base is provided with nine pulley assemblies. The nine line drive components and the nine pulley assemblies are all evenly arranged at circumferential intervals around the axis of the mounting base. Each pulley assembly includes a first fixed pulley and a second fixed slider. The direction of the line connecting the first fixed pulley and the second fixed slider is the same as the radial direction of the mounting base. Each line drive component is matched with one pulley assembly. The drive lines in the line drive components pass sequentially through the wire hole, the first fixed pulley, the second fixed slider, the mounting base, and the base plate, and are fixedly connected to the support disc located at the end of the first arm segment, the second arm segment, or the third arm segment.

[0024] The pulley assembly protects the drive cable, preventing it from breaking due to direct friction between the drive cable and the mounting base, thus making the acupuncture flexible robotic arm more stable and reliable.

[0025] Furthermore, each of the support discs is fixedly connected to the outer wall of the flexible hose by a clamp.

[0026] The present invention also provides a method of using a flexible acupuncture robotic arm, comprising:

[0027] Step 1: Use a depth camera to acquire the coordinate information of human acupoints and transmit the acquired coordinate information of human acupoints to the control system;

[0028] Step 2: Use the coordinates of human acupoints as the robot's end-effector pose, and solve for the virtual joint variables based on the end-effector pose equation;

[0029] Step 3: The control system controls the rotation of the winding wheel in the nine line drive components according to the virtual joint variable, changes the length of the drive line, controls the flexible tube to reach the desired position and the needle on it to reach the desired position. After the needle reaches the desired position, it is inserted into the acupoint to achieve the purpose of acupuncture treatment.

[0030] Furthermore, in step 1, the method for the depth camera to acquire the coordinate information of human acupoints includes:

[0031] Step 1.1: Acquire patient images using a depth camera and preprocess the images.

[0032] Step 1.2: Train the YOLOv5 model using the acquired patient images;

[0033] Step 1.3: Use the YOLOv5 model to detect the patient and obtain the two-dimensional coordinates of the target acupoints;

[0034] Step 1.4: Register the two-dimensional coordinates of the target acupoint with the depth data in the patient's human body image to obtain the Cartesian space coordinates of the target acupoint.

[0035] In step 2, the method for solving the virtual joint variables based on the end-effector pose equation is as follows:

[0036] Step 2.1 Treat one segment of the flexible hose as an equivalent constant curvature rod and define the virtual joint variable q as:

[0037]

[0038] Where θ1 is the bending angle of the first arm segment; θ1 is the rotation angle of the first arm segment; θ2 is the bending angle of the first arm segment; θ3 is the rotation angle of the first arm segment; θ3 is the bending angle of the first arm segment. Let be the rotation angle of the first arm segment; T is the transpose of the matrix;

[0039] Step 2.2: Establish the motion pose error equation based on the virtual joint angle vector, and take the pose tracking error e as the controlled variable, and the joint angular velocity... As the control variable, the control objective is to find a control law that makes the pose tracking error e converge to zero within a specified time. The joint angular velocity is then solved using nonlinear control theory. The kinematic pose error equation from the workspace to the arm segment space is completed. The kinematic pose error equation is as follows:

[0040]

[0041] in, It is a matrix;

[0042] Step 2.3, Obtain the joint variable q: Define the following system:

[0043]

[0044] In the formula, x = [x1, x2, ..., x n ] Τ ∈R n It is a state vector, f(x): D→R n The system is continuous in the neighborhood of the origin x = 0, and f(0) = 0; the system is globally fixed-time stable, and T max It is the smallest upper bound of the convergence time T(x0), i.e. Then the equilibrium point of system (3.1-1) is predefined time stable;

[0045] Define a scalar system as follows:

[0046]

[0047] Where 0 < m < 1, T c>0. g(x): D→R is continuous in the neighborhood of D∈(0,∞), and g(0)=0; when:

[0048] 1)

[0049] 2) g(x) is a bounded function;

[0050] 3)

[0051]

[0052] Then the scalar system is predefined time-stable;

[0053] The desired response of robot pose kinematics is expressed as:

[0054]

[0055] In the formula,

[0056] From equations 1 and 2, we can obtain

[0057]

[0058] Then the joint angular velocity is

[0059]

[0060] In the formula, T c This is the expected convergence time; the trajectory planning error will converge to zero, and the minimum upper bound of the convergence time is T. c ;

[0061] right Integrating over the time domain yields the virtual joint variables.

[0062] Furthermore, in step 3, the formula for calculating the change in the length of the drive line is:

[0063]

[0064] Where, Δl 11 Δl 12 and Δl 13 These represent the changes in rope length of the three drive lines on the first arm segment, Δl and Δl, respectively. 21 Δl 22 and Δl 23 These represent the changes in rope length of the three drive lines on the second arm segment, Δl and Δl, respectively. 31 Δl 32 and Δl 33These represent the changes in rope length of the three drive lines on the third arm segment; r is the center distance between the through hole and the flexible hose; θ1 is the bending angle of the first arm segment. θ1 is the rotation angle of the first arm segment; θ2 is the bending angle of the first arm segment; θ3 is the rotation angle of the first arm segment; θ3 is the bending angle of the first arm segment. The rotation angle of the first arm segment.

[0065] Furthermore, in step 3, the control system controls the motor to drive the winding wheel to rotate using a dual-loop PID method, including the following steps:

[0066] Step 3.1: Input the motor speed, obtain the motor speed using the motor encoder, calculate the speed deviation, and use the PID algorithm to calculate the output of the speed loop controller as the set value of the current loop.

[0067] Step 3.2: Input the motor speed, obtain the motor speed using the motor encoder, calculate the speed deviation, and use the PID algorithm to calculate the output of the speed loop controller as the set value of the current loop.

[0068] Step 3.3: Use the output of the current loop to control the duty cycle, thereby controlling the motor speed.

[0069] The beneficial effects of this invention are as follows:

[0070] 1. The present invention discloses a flexible acupuncture robotic arm and its method of use. By setting a support disk on a flexible tube and using a line drive, the execution end of the flexible tube and the needle and depth camera on it move according to a predetermined trajectory, thereby driving the needle to insert into the acupoints of the human body to achieve the purpose of acupuncture treatment. Due to the setting of the flexible tube, the entire robotic arm is flexible. Even if the robotic arm collides with the patient's body when the patient moves, it will not cause injury to the patient, thus improving the safety of use. Compared with traditional rigid robots, the flexible acupuncture robotic arm of the present invention is safer in human-computer interaction.

[0071] 2. The acupuncture flexible robotic arm of the present invention protects the drive line by setting a pulley assembly, avoiding the problem of drive line breakage caused by direct friction between the drive line and the mounting base, thus making the acupuncture flexible robotic arm more stable and reliable. Attached Figure Description

[0072] Figure 1 This is a schematic diagram of the structure of a flexible robotic arm for acupuncture.

[0073] Figure 2 This is a partially enlarged structural diagram of the flexible hose.

[0074] Figure 3 This is a schematic diagram of the installation structure for multiple line drive devices.

[0075] Figure 4 This is an enlarged structural diagram of the end of the flexible hose.

[0076] Figure 5 This is a schematic diagram of the bending deformation of the arm segment.

[0077] Figure 6 This is a flowchart of the dual-loop PID method.

[0078] Figure 7 This is a schematic diagram of the working principle of an optical fiber sensor.

[0079] The components include: 1. Wire drive device; 2. Mounting base plate; 3. Wire drive component; 4. Flexible hose; 401. First arm segment; 402. Second arm segment; 403. Third arm segment; 5. Support disc; 6. Needle; 7. Depth camera; 8. Winding wheel; 9. Drive line; 10. Base plate; 11. Through hole; 12. Support frame; 13. Support column; 14. Motor; 15. Wire through hole; 16. Pulley assembly; 17. First fixed pulley; 18. Second fixed slider; 19. Clamp. Detailed Implementation

[0080] The specific embodiments of the present invention are described below to enable those skilled in the art to understand the present invention. However, it should be understood that the present invention is not limited to the scope of the specific embodiments. For those skilled in the art, various changes are obvious as long as they are within the spirit and scope of the present invention as defined and determined by the appended claims. All inventions utilizing the concept of the present invention are protected.

[0081] like Figures 1-4 As shown, the present invention provides an acupuncture flexible robotic arm, which includes a control system and a wire drive device 1 electrically connected to the control system. The wire drive device 1 includes a mounting base 2 and multiple wire drive components 3.

[0082] A flexible tube 4 is mounted on the mounting base plate 2. Multiple support discs 5 are evenly spaced along the length of the flexible tube 4 on its outer wall. Each support disc 5 has multiple through holes 11. A needle 6, a depth camera 7, and a fiber optic sensor are mounted at the end of the flexible tube 4. The depth camera 7 and the fiber optic sensor are electrically connected to the control system. Each line drive component 3 includes a rotating winding wheel 8, and a drive line 9 is wound on each winding wheel 8. The drive lines 9 of the multiple line drive components 3 pass through the multiple through holes 11 and are fixedly connected to the support discs 5 located at the end of the flexible tube 4.

[0083] By setting a support disk 5 on the flexible tube 4 and using a wire drive, the actuator end of the flexible tube 4 and the needle 6, depth camera 7 and fiber optic sensor on it move according to a predetermined trajectory, driving the needle 6 to insert into the acupoints of the human body to achieve the purpose of acupuncture treatment; the fiber optic sensor is used to detect the bending angle and bending plane angle of the flexible tube 4 and provide real-time feedback to improve the motion accuracy of the actuator end of the flexible tube 4; due to the setting of the flexible tube 4, the entire robotic arm is flexible, and even if the robotic arm collides with the patient's body when the patient moves, it will not cause injury to the patient, improving the safety of use. Compared with traditional rigid robots, the acupuncture flexible robotic arm in this invention is safer in human-computer interaction.

[0084] Furthermore, in a specific arrangement of the flexible hose 4 and multiple support discs 5, the flexible hose 4 includes a first arm segment 401, a second arm segment 402 and a third arm segment 403 connected to each other; three support discs 5 are evenly spaced along their own length direction on the outer walls of the first arm segment 401, the second arm segment 402 and the third arm segment 403.

[0085] One end of the first boom segment 401 is fixedly connected to the center of the mounting base plate 2 via the base plate 10;

[0086] Each supporting disk has a radius of r. a Nine through holes 11 are evenly arranged circumferentially on the pitch circle;

[0087] There are 9 wire drive components 3, with 3 wire drive components 3 matched to the first arm segment 401, the second arm segment 402 and the third arm segment 403;

[0088] Three drive lines 9 of the three line drive components 3 that are matched with the first arm segment 401 pass through the through holes 11 on the three support disks 5 and are fixedly connected to the support disk 5 located at the end of the first arm segment 401; the included angle between the three drive lines 9 that cooperate with the first arm segment 401 is 120°.

[0089] Three drive lines 9 of the three line drive components 3 that are matched with the second arm segment 402 pass through the through holes 11 on the six support disks 5 and are fixedly connected to the support disk 5 located at the end of the second arm segment 402; the included angle between the three drive lines 9 that are matched with the second arm segment 402 is 120°.

[0090] Three drive lines 9 of the three line drive components 3 that are matched with the third arm segment 403 pass through the through holes 11 on the nine support disks 5 and are fixedly connected to the support disks 5 located at the end of the third arm segment 403; the included angle between the three drive lines 9 that cooperate with the third arm segment 403 is 120°; the needle 6 and the depth camera 7 are both located at the end of the third arm segment 403.

[0091] The first arm segment 401, the second arm segment 402, and the third arm segment 403 are all redundantly driven by three line drive components 3, thereby realizing the end 2 degrees of freedom bending motion of the first arm segment 401, the second arm segment 402, and the third arm segment 403, and finally realizing the six degrees of freedom control of the entire flexible hose 4 at the execution end.

[0092] Furthermore, each via 11 is provided with a drive line 9. This arrangement can avoid the problem of multiple drive lines 9 moving unsmoothly when installed in a single via 11.

[0093] like Figure 3 As shown, further, as a specific arrangement of the wire drive device 1, the wire drive device 1 also includes a support frame 12 disposed below the mounting base 2, and the lower end face of the mounting base 2 is fixedly connected to the upper end face of the support frame 12 through multiple support columns 13.

[0094] Nine motors 14 are installed inside the support frame 12. The output shaft of each motor 14 passes through the top of the support frame 12 and is connected to a winding wheel 8. Each winding wheel 8 is located between the support frame 12 and the mounting base 2. Each winding wheel 8 has a wire hole 15 at its top. The drive wire 9 on each winding wheel 8 passes through the wire hole 15, the mounting base 2 and the base plate 10 in sequence and is fixedly connected to the support disc 5 located at the end of the first arm segment 401, the second arm segment 402 or the third arm segment 403.

[0095] In the above technical solution, the motor 14 realizes the rotation of the winding wheel 8, thereby realizing the winding or unwinding of the drive line 9 on the winding wheel 8; and the wire hole 15 is set to guide the drive line 9, so that the drive line 9 is neatly arranged on the winding wheel 8 during the winding or unwinding operation.

[0096] like Figure 1 and Figure 3 As shown, further, the lower end face of the mounting base 2 is provided with 9 pulley assemblies 16, and the 9 line drive components 3 and 9 pulley assemblies 16 are all evenly arranged in a ring at intervals around the axis of the mounting base 2; each pulley assembly 16 includes a first fixed pulley 17 and a second fixed slider 18, and the direction of the line connecting the first fixed pulley 17 and the second fixed slider 18 is the same as the radial direction of the mounting base 2; each line drive component 3 is matched with one pulley assembly 16; the drive line 9 in the line drive component 3 passes through the wire hole 15, the first fixed pulley 17, the second fixed slider 18, the mounting base 2 and the base plate 10 in sequence and is fixedly connected to the support disc 5 located at the end of the first arm segment 401, the second arm segment 402 or the third arm segment 403.

[0097] The pulley assembly 16 serves to protect the drive line 9, preventing the drive line 9 from breaking due to direct friction with the mounting base 2, thus making the acupuncture flexible robotic arm more stable and reliable.

[0098] Furthermore, each support disc 5 is fixedly connected to the outer wall of the flexible hose 4 by clamps 19.

[0099] The present invention also provides a method of using a flexible acupuncture robotic arm, comprising:

[0100] Step 1: Use depth camera 7 to acquire the coordinate information of human acupoints and transmit the acquired coordinate information of human acupoints to the control system;

[0101] Step 2: Use the coordinates of human acupoints as the robot's end-effector pose, and solve for the virtual joint variables based on the end-effector pose equation;

[0102] Step 3: The control system controls the rotation of the winding wheel 8 in the nine line drive components 3 according to the virtual joint variables, changes the length of the drive line 9, controls the flexible hose 4 to execute the end and the needle 6 on it to reach the desired position. After the needle 6 reaches the desired position, it is inserted into the acupoint to achieve the purpose of acupuncture treatment.

[0103] Furthermore, in step 1, the method by which the depth camera 7 acquires the coordinate information of human acupoints includes:

[0104] Step 1.1: Depth camera 7 acquires images of the patient's body and preprocesses the images;

[0105] Step 1.2: Train the YOLOv5 model using the acquired patient images;

[0106] Step 1.3: Use the YOLOv5 model to detect the patient and obtain the two-dimensional coordinates of the target acupoints;

[0107] Step 1.4: Register the two-dimensional coordinates of the target acupoint with the depth data in the patient's human body image to obtain the Cartesian space coordinates of the target acupoint.

[0108] like Figure 5 As shown, in step 2, the method for solving the virtual joint variables based on the end-effector pose equation is as follows:

[0109] Step 2.1 Equivalently represent one segment of the flexible hose 4 as a rod with constant curvature, and define the virtual joint variable q as:

[0110]

[0111] Wherein, θ1 is the bending angle of the first arm segment 401; θ1 is the rotation angle of the first arm segment 401; θ2 is the bending angle of the first arm segment 401. θ3 is the rotation angle of the first arm segment 401; θ3 is the bending angle of the first arm segment 401. Let be the rotation angle of the first arm segment 401; T is the transpose of the matrix;

[0112] Step 2.2: Establish the motion pose error equation based on the virtual joint angle vector, and take the pose tracking error e as the controlled variable, and the joint angular velocity... As the control variable, the control objective is to find a control law that makes the pose tracking error e converge to zero within a specified time. The joint angular velocity is then solved using nonlinear control theory. The kinematic pose error equation from the workspace to the arm segment space is completed. The kinematic pose error equation is as follows:

[0113]

[0114] in, It is a matrix;

[0115] Step 2.3, Obtain the joint variable q: Define the following system:

[0116]

[0117] In the formula, x = [x1, x2, ..., x n ] Τ ∈R n It is a state vector, f(x): D→R n The system is continuous in the neighborhood of the origin x = 0, and f(0) = 0; the system is globally fixed-time stable, and T max It is the smallest upper bound of the convergence time T(x0), i.e. Then the equilibrium point of system (3.1-1) is predefined time stable;

[0118] Define a scalar system as follows:

[0119]

[0120] Where 0 < m < 1, T c >0. g(x): D→R is continuous in the neighborhood of D∈(0,∞), and g(0)=0; when:

[0121] 1)

[0122] 2) g(x) is a bounded function;

[0123] 3)

[0124]

[0125] Then the scalar system is predefined time-stable;

[0126] The desired response of robot pose kinematics is expressed as:

[0127]

[0128] In the formula,

[0129] From equations 1 and 2, we can obtain

[0130]

[0131] Then the joint angular velocity is

[0132]

[0133] In the formula, T c This is the expected convergence time; the trajectory planning error will converge to zero, and the minimum upper bound of the convergence time is T. c ;

[0134] right Integrating over the time domain yields the virtual joint variables.

[0135] Furthermore, in step 3, the formula for calculating the length of the drive line 9 is as follows:

[0136]

[0137] Where, Δl 11 Δl 12 and Δl 13 These represent the changes in rope length of the three drive lines 9 on the first arm segment 401, respectively; Δl 21 Δl 22 and Δl 23 These represent the changes in rope length of the three drive lines 9 on the second arm segment 402, respectively; Δl 31 Δl 32 and Δl 33 These represent the changes in rope length of the three drive lines 9 on the third arm segment 403; r is the center distance between the through hole 11 and the flexible hose 4; θ1 is the bending angle of the first arm segment 401. θ1 is the rotation angle of the first arm segment 401; θ2 is the bending angle of the first arm segment 401. θ3 is the rotation angle of the first arm segment 401; θ3 is the bending angle of the first arm segment 401. This is the rotation angle of the first arm segment 401.

[0138] Fiber optic sensors are used to detect the bending angle and bending plane angle of the flexible hose 4 and provide real-time feedback, improving the motion accuracy of the flexible hose 4's actuator end; such as Figure 7 As shown, the specific principle of the fiber optic sensor is as follows:

[0139] Each cross-section of the fiber optic sensor has three unidirectional gratings, with a spacing of 120° between adjacent gratings. The initial length of cross-section i (i = 1, 2, ..., n) is l. i0 The initial radius is r i l i0 'and r i ' represents the length and radius of section i after deformation, and the generatrix of the grating j of section i is l. ij (j=1,2,3), the wavelength λ can be obtained through a demodulator. ij The initial value is λ ij0 ε ijFBG For the strain of grating j, ε ij For axially coupled strain, h ij The initial vertical length of grating j in section i after expanding the grating region.

[0140] The change in axial elongation / compression ratio includes tensile deformation and bending deformation. (The last part, ε, appears to be a typo and can be omitted.) ij Divided into axial tensile strain ε ij1 and bending strain ε ij2 It can be calculated using the following formula:

[0141]

[0142] In the formula, p e Let represent the photoelastic coefficient; α is the helix angle; μ is Poisson's ratio. In section i, the angle of the bending plane... curvature k i and bending angle θ i The deformation parameters can be calculated using the following formula:

[0143]

[0144]

[0145] The change in rope length Δl is obtained from step three. ij Let the radius of the winding wheel 8 be R, and the angular velocity be... The number of revolutions is n c =Δl ij / 2πr, the motor speed is RPM, and the number of revolutions is n. c .

[0146] like Figure 6As shown, further, in step 3, the control system controls the motor 14 to drive the winding wheel 8 to rotate using a dual-loop PID method, including the following steps:

[0147] Step 3.1: Input the speed of motor 14, obtain the speed of motor 14 using the encoder of motor 14, calculate the speed deviation, and use the PID algorithm to calculate the output of the speed loop controller as the set value of the current loop.

[0148] Step 3.2: Input the speed of motor 14, obtain the speed of motor 14 using the encoder of motor 14, calculate the speed deviation, and use the PID algorithm to calculate the output of the speed loop controller as the set value of the current loop.

[0149] Step 3.3: Use the output of the current loop to control the duty cycle, thereby controlling the speed of motor 14.

[0150] In summary, the acupuncture flexible robotic arm and its method of use in this invention utilize a wire-driven approach to move the end of the flexible tube 44, the needle 66 attached to it, and the depth camera 77 along a predetermined trajectory, thereby driving the needle 66 to insert into acupoints to achieve acupuncture treatment. When using the acupuncture flexible robotic arm to perform acupuncture on a patient, even if the flexible tube 44 collides with the patient's body, it will not cause injury, thus improving safety. Compared to traditional rigid robots, the acupuncture flexible robotic arm in this invention is safer in human-computer interaction, solving the safety hazard of collisions with the patient's body that often occurs with rigid multi-axis robotic arms used to move needles in robotic acupuncture systems.

Claims

1. A flexible acupuncture robotic arm, characterized in that, The system includes a control system and a line drive device electrically connected to the control system, the line drive device including a mounting base and a plurality of line drive components; A flexible tube is provided on the mounting base plate. Multiple support discs are evenly spaced along the length of the flexible tube on its outer wall. Each support disc is provided with multiple through holes. A needle, a depth camera, and a fiber optic sensor are provided at the end of the flexible tube. The depth camera is electrically connected to the control system. Each wire drive component includes a rotating winding wheel, on which a drive wire is wound; the drive wires of the multiple wire drive components pass through the multiple through holes and are fixedly connected to a support disc located at the end of the flexible hose. The flexible hose includes a first arm segment, a second arm segment, and a third arm segment that are connected to each other; three support discs are evenly spaced along their length on the outer walls of the first arm segment, the second arm segment, and the third arm segment. One end of the first arm segment is fixedly connected to the center of the mounting base plate via a base plate; The radius of each supporting disk is r a Nine vias are evenly arranged circumferentially on each of the pitch circles; The number of the wire drive components is 9, with 3 wire drive components matched to each of the first arm segment, the second arm segment, and the third arm segment; Three of the three drive lines of the three line drive components that are matched with the first arm segment pass through the through holes on the three support discs and are fixedly connected to the support disc located at the end of the first arm segment; the included angle between the three drive lines that are matched with the first arm segment is 120°; Three of the three drive lines of the three line drive components that are matched with the second arm segment pass through the through holes on the six support discs and are fixedly connected to the support disc located at the end of the second arm segment; the included angle between the three drive lines that cooperate with the second arm segment is 120°; Three of the three drive lines of the three line drive components that are matched with the third arm segment pass through the through holes on the nine support discs and are fixedly connected to the support disc located at the end of the third arm segment; the included angle between the three drive lines that cooperate with the third arm segment is 120°; the needle and the depth camera are both located at the end of the third arm segment; The line drive device also includes a support frame disposed below the mounting base, and the lower end face of the mounting base is fixedly connected to the upper end face of the support frame through multiple support columns. Nine motors are installed inside the support frame. The output shaft of each motor passes through the top of the support frame and is connected to a winding wheel. Each winding wheel is located between the support frame and the mounting base. Each winding wheel has a wire hole at its top. The drive wire on each winding wheel passes through the wire hole, the mounting base, and the base plate in sequence and is fixedly connected to the support disc located at the end of the first arm segment, the second arm segment, or the third arm segment. The control system uses the coordinates of human acupoints as the robot's end-effector pose and calculates virtual joint variables based on the end-effector pose equation. The method for calculating virtual joint variables based on the end-effector pose equation is as follows: Step 2.1 Treat one segment of the flexible hose as an equivalent constant curvature rod and define virtual joint variables. q for: in, The bending angle of the first arm segment; The rotation angle of the first arm segment; The bending angle of the first arm segment; The rotation angle of the first arm segment; The bending angle of the first arm segment; Let be the rotation angle of the first arm segment; T is the transpose of the matrix; Step 2.2: Establish the kinematic pose error equation based on the virtual joint angle vector, and incorporate the pose tracking error. e As a controlled variable, joint angular velocity As the control variable, the control objective is to find a control law that minimizes the pose tracking error. e The joint angular velocity converges to zero within a specified time, and is then calculated using nonlinear control theory. The motion posture error equation from the workspace to the arm segment space is completed, and the motion posture error equation is as follows: (Equation 1) in, It is a matrix; Step 2.3: Obtain joint variables q Define a system as follows: In the formula, It is a state vector. At the origin The neighborhood of is contiguous, and The system is globally stable at a fixed time, and It is the convergence time. The least upper bound, i.e. , Then the equilibrium point of system (3.1-1) is predefined time stable; Define a scalar system as follows: in, , , exist The neighborhood of is contiguous, and When the following conditions are met: 1) ； 2) It is a bounded function; 3) , ； Then the scalar system is predefined time-stable; The desired response of robot pose kinematics is expressed as: (Equation 2) In the formula, , , ; From equations 1 and 2, we can obtain Then the joint angular velocity is In the formula, This is the expected convergence time; the error of trajectory planning will converge to zero, and the minimum upper bound of the convergence time is... ; right Integrating over the time domain yields the virtual joint variables. ; The control system uses a dual-loop PID method to control the motor to drive the winding wheel to rotate, including the following steps: Step 3.1: Input the motor speed, obtain the motor speed using the motor encoder, calculate the speed deviation, and use the PID algorithm to calculate the output of the speed loop controller as the set value of the current loop. Step 3.2: Input the motor speed, obtain the motor speed using the motor encoder, calculate the speed deviation, and use the PID algorithm to calculate the output of the speed loop controller as the set value of the current loop. Step 3.3: Use the output of the current loop to control the duty cycle, thereby controlling the motor speed; The formula for calculating the change in the length of the drive line is: in, , and These represent the changes in rope length of the three drive lines on the first arm segment, respectively. , and These represent the changes in rope length of the three drive lines on the second arm segment, respectively. , and These represent the changes in rope length of the three drive lines on the third arm segment, respectively. r This refers to the center distance between the through-hole and the flexible hose; The bending angle of the first arm segment; The rotation angle of the first arm segment; The bending angle of the first arm segment; The rotation angle of the first arm segment; The bending angle of the first arm segment; The rotation angle of the first arm segment.

2. The acupuncture flexible robotic arm according to claim 1, characterized in that, Each of the vias is provided with a drive line.

3. The acupuncture flexible robotic arm according to claim 2, characterized in that, Nine pulley assemblies are provided on the lower end face of the mounting base. The nine line drive components and the nine pulley assemblies are all evenly arranged in a ring at intervals around the axis of the mounting base. Each pulley assembly includes a first fixed pulley and a second fixed slider. The direction of the line connecting the first fixed pulley and the second fixed slider is the same as the radial direction of the mounting base. Each line drive component is matched with one pulley assembly. The drive lines in the line drive component pass sequentially through the wire hole, the first fixed pulley, the second fixed slider, the mounting base plate, and the base plate, and are fixedly connected to the support disc located at the end of the first arm segment, the second arm segment, or the third arm segment.

4. The acupuncture flexible robotic arm according to claim 3, characterized in that, Each of the support discs is fixedly connected to the outer wall of the flexible hose by a clamp.

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