Method and system for controlling robotic arm pressing force based on pulse wave signal

Abstract

Disclosed are a method and system for controlling a robotic arm pressing force based on a pulse wave signal. The method comprises: acquiring a pulse wave signal of a target; acquiring an interaction force between an end of a robotic arm and the target, and determining an expected pressing force according to a mapping relation between a pressing effect and the pulse wave signal; establishing an admittance control model to convert the expected pressing force into an expected trajectory of the robotic arm; and determining, on the basis of an error between an actual trajectory and the expected trajectory of the robotic arm, a control quantity of the subsequent movement of the robotic arm by using a PID controller, so as to achieve the tracking of the expected trajectory. The present invention achieves a low-impedance and compliant interaction effect when the target of pressing is moving.

Description

A method and system for controlling the pressing force of a robotic arm based on a pulse wave signal Technical Field

[0001] The present invention relates to the field of computer application technology, and more specifically, to a method and system for controlling the pressing force of a robotic arm based on a pulse wave signal, which is particularly suitable for a scenario of pressing and stopping bleeding at a femoral artery puncture point. Background Art

[0002] Cardiac interventional therapy has become a common treatment for cardiovascular diseases such as coronary heart disease, arrhythmia, congenital heart disease, and valvular heart disease. The radial artery and femoral artery are the main surgical routes for cardiac interventional therapy. The femoral artery is easier to puncture and operate with a catheter due to its larger diameter, and has unmatched advantages over other interventional routes when dealing with some complex lesions. However, precisely because of the large diameter and rapid blood flow of the femoral artery, the difficulty in stopping bleeding immediately after surgery is another problem that plagues interventional surgeons. There are usually three methods for hemostasis at the femoral artery puncture point: manual compression hemostasis, mechanical compression, and vascular closure device hemostasis. Traditional manual compression methods take a long time to press (compression hemostasis takes about 25 minutes after extubation), are difficult to control, have poor hemostatic effects, and require long periods of limb immobilization for patients. This not only increases the workload of doctors, but also aggravates the discomfort and pain of patients, and even leads to symptoms such as urinary retention or back pain. Recently developed arterial puncture closure devices and femoral artery compression hemostat devices cannot simulate the local compression force applied by human operators to different individual puncture points due to individual physiological differences in patients (such as vascular conditions and weight). They often increase the risk of postoperative complications due to misplaced or inappropriate pressure.

[0003] Currently, commonly used femoral artery compression hemostat devices include lifting bracket type, inflatable type, and rotary type. In recent years, electronic pressure hemostat devices have gained popularity due to breakthroughs in ergonomic stability and controllability. However, relevant clinical application research results show that while these devices shorten postoperative bed rest and hospital stays and improve patient comfort to a certain extent, due to the lack of real-time monitoring and feedback of physiological signals such as the patient's dorsalis pedis artery pulse and the inability to adjust the pressure in real time, the clinical complication rate of patients using such devices is not necessarily lower than that of manual compression. Therefore, there is an urgent need to utilize robotic technology to design a dedicated puncture point immediate hemostasis operation mechanism that can adaptively select the appropriate compression method based on real-time patient vital signs, forming a closed loop between the compression operation and the patient's vital sign monitoring, thereby improving convenience, flexibility, patient comfort, and reducing the incidence of postoperative complications.

[0004] In terms of force control strategies for compression hemostasis robots, commonly used force control methods include impedance control, hybrid force / position control, and intelligent control. The impedance control method continuously adjusts the target impedance parameters by actually detecting the force between the robot and the environment, and then controls the robot's position through a position controller to ultimately achieve force control. The hybrid force / position control method decomposes the robot's motion space into force control space and position control space through a selection matrix, assigning a control method to each joint to achieve separate force and position control of the entire robot. Intelligent control methods include neural network control, optimization algorithm control, deep reinforcement learning, etc. However, data-driven intelligent control methods have problems such as complex models, large number of parameters, and difficulty in collecting data sets. In addition, the trained model has poor robustness and is expensive. In the hybrid force / position control method, it is not easy to clearly divide the pressing action into the appropriate selection matrix in the task of compression hemostasis.

[0005] In summary, the existing puncture point compression hemostasis technology has the following defects: the pressing force cannot be adaptively adjusted according to different patients' body shape, blood pressure and other physiological parameters; the patient's braking time during the compression process is long, and the pressing force cannot be adaptively adjusted according to the patient's posture changes; the data-driven intelligent control method of pressing force has poor robustness and high training costs.

[0006] Summary of the Invention

[0007] The purpose of the present invention is to overcome the above-mentioned defects of the prior art and provide a method and system for controlling the pressing force of a robotic arm based on a pulse wave signal.

[0008] According to a first aspect of the present invention, a method for controlling the pressing force of a robotic arm based on a pulse wave signal is provided. The method comprises the following steps:

[0009] Collecting the target's pulse wave signal;

[0010] Obtaining the interaction force between the end of the robotic arm and the target, and determining the expected pressing force based on the mapping relationship between the pressing effect and the pulse wave signal;

[0011] Establishing an admittance control model to convert the desired pressing force into a desired trajectory of the robotic arm;

[0012] Based on the error between the actual trajectory of the robot arm and the expected trajectory, a PID controller is used to determine the control amount of the subsequent movement of the robot arm to achieve tracking of the expected trajectory.

[0013] According to a second aspect of the present invention, a pulse wave signal-based robotic arm compression force control system is provided. The system includes a signal acquisition and processing module, an admittance control model, a PID controller, and a robotic arm. The signal acquisition and processing module is configured to acquire a target's pulse wave signal and obtain the interaction force between the robotic arm's end and the target, thereby determining a desired compression force based on a mapping relationship between the compression effect and the pulse wave signal. The admittance control model is configured to convert the desired compression force into a desired trajectory for the robotic arm. The PID controller is configured to determine the control amount for subsequent movement of the robotic arm based on the error between the robotic arm's actual trajectory and the desired trajectory, thereby tracking the desired trajectory.

[0014] Compared with the existing technology, the advantage of the present invention is that it proposes a method for adaptively controlling the pressing force of a hemostatic robot. According to clinical experience, the pressing force on the femoral artery is different, and the amplitude of the pulse wave collected at the end of the lower limb will change accordingly. As the pressing force on the femoral artery puncture point increases, the amplitude of the pulse wave will gradually decrease. When the pressing force completely cuts off the propagation of the pulse wave, the amplitude of the pulse wave collected at the end of the lower limb is zero. Based on this relationship between the pulse wave amplitude and the pressing force at the puncture point, the present invention proposes a method for adaptively adjusting the pressing force of a puncture point hemostatic robot arm based on pulse wave feedback, which improves the effectiveness and comfort of hemostasis by pressing.

[0015] Further features and advantages of the present invention will become apparent from the following detailed description of exemplary embodiments of the present invention with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention.

[0017] FIG1 is a flow chart of a method for controlling the pressing force of a robotic arm based on a pulse wave signal according to an embodiment of the present invention;

[0018] FIG2 is a schematic diagram of the overall process of a method for controlling the pressing force of a robotic arm based on a pulse wave signal according to an embodiment of the present invention;

[0019] FIG3 is a schematic diagram of an admittance control model according to an embodiment of the present invention;

[0020] FIG4 is a schematic diagram of the overall process of executing a follow-up control task according to an embodiment of the present invention. DETAILED DESCRIPTION

[0021] Various exemplary embodiments of the present invention will now be described in detail with reference to the accompanying drawings. It should be noted that unless otherwise specifically stated, the relative arrangement of components and steps, numerical expressions and numerical values ​​set forth in these embodiments do not limit the scope of the present invention.

[0022] The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way intended to limit the invention, its application, or uses.

[0023] Technologies, methods, and equipment known to ordinary technicians in the relevant art may not be discussed in detail, but where appropriate, the technologies, methods, and equipment should be considered part of the specification.

[0024] In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not limiting. Therefore, other examples of the exemplary embodiments may have different values.

[0025] It should be noted that like reference numerals and letters refer to like items in the following figures, and therefore, once an item is defined in one figure, it need not be further discussed in subsequent figures.

[0026] In general, the method for controlling the pressing force of a robotic arm based on a pulse wave signal provided by the present invention first associates different pressing strategies with the patient's physiological signals by integrating the pulse wave signal as a standard for measuring whether the pressing force is appropriate; then, by establishing an admittance control model (or admittance controller), the measured actual pressure and the expected pressing force are used as model inputs to obtain the expected trajectory, and finally, the trajectory of the robotic arm is driven by a servo control system to accurately track the expected trajectory, and the servo control system uses a position controller to realize the control of the pressing force of the robotic arm. The present invention can be used for pressing force control in a variety of scenarios, and is particularly suitable for pressing to stop bleeding, such as pressing to stop bleeding at the femoral artery puncture point. In the following, the idea of ​​the present invention will be mainly introduced with respect to the pressing to stop bleeding scenario.

[0027] Specifically, as shown in FIG1 and FIG2 , the provided method for controlling the pressing force of a robotic arm based on a pulse wave signal includes the following steps:

[0028] Step S110 : determining the expected pressing force of the robotic arm according to the mapping relationship between the pressing effect and the pulse wave signal.

[0029] To achieve effective compression and hemostasis after a puncture procedure, appropriate pressure is crucial. In one embodiment, pressure is adjusted based on the real-time pulse wave signal amplitude collected at the extremity of the limb being pressed. Based on the clinician's experience in compression and hemostasis, the pressure is adjusted to an optimal value, maintaining the pulse wave signal amplitude at the end of the compression at 70% of the normal amplitude. To account for individual differences in patient posture and physiological conditions, the desired pressure must be adjusted before each compression. This can be achieved by designing an integrated multi-parameter measurement module to measure and record the pulse wave signal, which serves as a standard for automatic adjustment of the desired pressure.

[0030] In addition, to obtain the desired compression force, it is necessary to measure the contact force between the human and the machine. For example, a flexible pressure array sensor is used to obtain the interaction force between the end of the robotic arm and the patient. To obtain a good mapping relationship between the compression effect and the pulse wave signal, the pulse wave measurement sensor is placed at the end of the ipsilateral limb for measurement. The specific steps include: the robotic arm automatically and continuously detects the patient's hemostasis area downward. After contacting the patient, it records the compression force and the pulse wave signal. As the compression force continues to increase and the pulse wave signal completely disappears, the pressure sensor information at this time is recorded and the pressing robotic arm is raised by 30%, and this compression force is maintained.

[0031] In this step, by measuring the interaction force and pulse wave signal between the human and the machine, and based on the mapping relationship between the pressing effect and the pulse wave signal, the expected pressing torque of the end of the hemostasis robot arm can be obtained.

[0032] Step S120 : establishing an admittance control model to convert the desired pressing force into a desired trajectory of the robotic arm.

[0033] When the patient maintains the same action for a long time, it will increase the patient's psychological and physical burden. In order to improve the patient's comfort when being pressed for a long time, ensure that the pressing force is constant and the position is not lost. In one embodiment, as shown in Figure 3, a position-based impedance control model, namely admittance control, is adopted. Its advantage is that the pressing force control can be completed by relying only on the kinematic model without establishing a mechanical arm dynamics model, and the position servo control of the motor is relatively complete. The position-based impedance control can give full play to its advantages. Conform to the human-machine contact force generated when the patient's body moves, and do not hinder its movement while maintaining constant force pressing. The admittance controller can be expressed as:

[0034] Among them, X r is the initial expected trajectory of the robot arm, X is the new expected trajectory of the robot arm, and F r is the expected pressing force of the robot arm, F e The contact force (or interaction force) between human and machine is obtained by selecting a suitable inertia matrix M.d , damping matrix B d , rigidity matrix K d Parameters to achieve smooth control. and are the second and first derivatives of X, respectively. and They are X r The second and first derivatives of F. e The actual pressure measured by the flexible pressure array sensor when pressing, F r Generated from 70% of the compression force when the pulse wave signal completely disappears, X r To maintain the initial pressing position constant over time, X represents the new pressing position trajectory generated by the admittance controller. This change in position indirectly influences the contact force between the human and the robot, maintaining a dynamic relationship between the motion trajectory of the hemostasis robot and the human-robot interaction force. By designing an admittance controller, the desired torque transformation can be converted into a desired position change.

[0035] Step S130: Using a PID controller to track the desired trajectory to perform a follow-up control task.

[0036] To achieve constant compression force tracking in response to the patient's various movements, maintaining normal compression and hemostasis even when the patient is lifted or translated, and taking into account the motor drive controller used by the robotic arm, in one embodiment, a PID controller is used to achieve tracking of the desired trajectory. The overall system control loop for performing the tracking control task is shown in Figure 4.

[0037] Specifically, the PID controller is expressed as: e(t)=x(t)-y(t) (3)

[0038] Among them, e(t) is the system error between the system input x(t) and the system output y(t), u(t) is the control quantity output to the robot arm, and by choosing a suitable ratio K p , integral K i , differential K d Parameters are used to achieve the effect of follow-up control. x(t) comes from the desired pressing force, and y(t) comes from the contact force generated by the interaction between the robot arm and the human. The trajectory change obtained by the above-mentioned admittance control model is used as the trajectory change of the robot arm in the task space, and the inverse kinematics model of the robot arm is used to convert the new trajectory into the angle values ​​of each motor joint. The actual joint angles are obtained through the encoders on the joints. Finally, the PID controller enables the robot arm to reach the target position, and the interaction force generated by it and the environment reacts to the admittance controller to form a double closed-loop control.

[0039] Accordingly, the present invention also provides a manipulator pressure control system based on a pulse wave signal, which is used to implement one or more aspects of the above-mentioned method. For example, the system includes a signal acquisition and processing module, an admittance control model, a PID controller, and a manipulator, wherein: the signal acquisition and processing module is used to acquire the pulse wave signal of the target and obtain the interaction force between the end of the manipulator and the target, and then determine the desired pressure based on the mapping relationship between the pressing effect and the pulse wave signal; the admittance control model is used to convert the desired pressure into the desired trajectory of the manipulator; the PID controller is used to determine the control amount of the subsequent movement of the manipulator based on the error between the actual trajectory of the manipulator and the desired trajectory, so as to achieve tracking of the desired trajectory. Functional modules such as the signal acquisition and processing module, the admittance control model, and the PID controller can be implemented using dedicated hardware or FPGA, or using a general-purpose processor combined with software.

[0040] To further validate the effectiveness of this invention, an experimental verification was conducted. Using a self-developed compression hemostasis robotic arm, the researchers performed hemostasis and continuously monitored physiological characteristics such as electrocardiogram (ECG), pulse, and respiration on beagle dogs following hind limb femoral artery puncture. The pressure applied at the hemostasis tip was adjusted based on the monitored pulse wave feedback, achieving a good hemostasis effect.

[0041] During the experimental verification process, after puncturing the left hind limb of the experimental dog, the arterial sheath was removed and the femoral artery puncture point was compressed using an instant hemostasis robot. First, the robotic arm was manually pulled above the puncture point and aligned with the puncture point. The upper computer display interface was controlled to press the robotic arm down and keep pressing for 20 minutes. Then, the pressing hemostasis robotic arm was removed and it was observed that there was no bleeding at the puncture point. The experiment of pressing to stop bleeding after femoral artery puncture on animal dogs proved that the developed robot for monitoring vital signs after percutaneous femoral artery intervention and stopping bleeding at the puncture point has a good hemostasis effect. After 20 minutes of automatic pressing to stop bleeding, it can effectively stop bleeding without causing internal bleeding.

[0042] Furthermore, during the compression process, the pulse wave at the extremity of the pressing side was observed to gradually decrease in amplitude as the pressing force increased. When the pressing force reached a certain threshold, the pulse wave disappeared. After the adaptive pressing force control algorithm detected the disappearance of the pulse wave, the pressing force stopped increasing and began to fall back, at which point the pulse wave was observed to reappear. Experimental results demonstrate that the developed puncture-point hemostasis robotic arm for percutaneous femoral artery intervention can adaptively adjust the pressing force based on the monitored pulse wave, ensuring optimal hemostasis and comfort.

[0043] In summary, compared with the prior art, the present invention has the following advantages:

[0044] 1) A compression hemostasis method based on real-time monitoring of the pulse wave signal amplitude to adaptively adjust the pressure at the puncture point is proposed. By using the real-time acquired pulse wave signal amplitude of the affected side to adjust the pressure at the puncture point, the hemostasis effect is ensured while improving patient comfort.

[0045] 2) A compression force control system combining an admittance controller, robotic arm kinematics, and a PID controller was designed. The admittance controller obtains the desired corrected trajectory in the task space, which is then converted into position instructions in the joint space through the robotic arm kinematics. Finally, the PID controller achieves tracking control of the desired trajectory. This position-based impedance control model, known as the admittance controller, is the most effective control strategy for compression hemostasis tasks. It maintains a certain relationship between external force and displacement, allowing movement in accordance with the patient's movements. This ensures compliant control while also achieving constant force tracking, achieving a low-impedance and compliant interaction effect when the patient's puncture site moves.

[0046] 3) Based on the relationship between the change in pressing force during compression of the femoral artery and the change in the amplitude of the pulse wave signal at the end of compression, the present invention combines the pressure sensor on the end effector of the robotic arm to achieve adaptive adjustment of the pressing force for different patients and different physiological conditions.

[0047] The present invention may be a system, a method and / or a computer program product. The computer program product may include a computer-readable storage medium carrying computer-readable program instructions for causing a processor to implement various aspects of the present invention.

[0048] Computer-readable storage medium can be a tangible device that can keep and store the instructions used by the instruction execution device.Computer-readable storage medium can be, for example, but not limited to, an electrical storage device, a magnetic storage device, an optical storage device, an electromagnetic storage device, a semiconductor storage device or any suitable combination thereof.More specific examples (non-exhaustive list) of computer-readable storage medium include: a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), a static random access memory (SRAM), a portable compact disc read-only memory (CD-ROM), a digital versatile disk (DVD), a memory stick, a floppy disk, a mechanical encoding device, for example, a punch card or a convex structure in a groove having instructions stored thereon, and any suitable combination thereof.Computer-readable storage medium used herein is not interpreted as a transient signal itself, such as radio waves or other freely propagating electromagnetic waves, electromagnetic waves propagated by waveguides or other transmission media (for example, light pulses by fiber optic cables), or electrical signals transmitted by wires.

[0049] The computer-readable program instructions described herein can be downloaded from a computer-readable storage medium to each computing / processing device, or downloaded to an external computer or external storage device via a network, such as the Internet, a local area network, a wide area network, and / or a wireless network. The network can include copper transmission cables, fiber optic transmission, wireless transmission, routers, firewalls, switches, gateway computers, and / or edge servers. The network adapter card or network interface in each computing / processing device receives the computer-readable program instructions from the network and forwards the computer-readable program instructions to be stored in the computer-readable storage medium in each computing / processing device.

[0050] The computer program instructions for performing the operation of the present invention can be assembly instructions, instruction set architecture (ISA) instructions, machine instructions, machine-dependent instructions, microcode, firmware instructions, state setting data, or source code or object code written in any combination of one or more programming languages, including object-oriented programming languages ​​such as Smalltalk, C++, Python, and conventional procedural programming languages ​​such as "C" language or similar programming languages. The computer readable program instructions can be executed entirely on the user's computer, partially on the user's computer, as an independent software package, partially on the user's computer, partially on a remote computer, or completely on a remote computer or server. In the case of a remote computer, the remote computer can be connected to the user's computer via any type of network, including a local area network (LAN) or a wide area network (WAN), or can be connected to an external computer (e.g., using an Internet service provider to connect via the Internet). In some embodiments, an electronic circuit, such as a programmable logic circuit, a field programmable gate array (FPGA), or a programmable logic array (PLA), is personalized by utilizing the state information of the computer readable program instructions, and the electronic circuit can execute the computer readable program instructions, thereby realizing various aspects of the present invention.

[0051] Various aspects of the present invention are described herein with reference to flowcharts and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the present invention. It should be understood that each block of the flowcharts and / or block diagrams, and combinations of blocks in the flowcharts and / or block diagrams, can be implemented by computer-readable program instructions.

[0052] These computer-readable program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing device, thereby producing a machine, so that when these instructions are executed by the processor of the computer or other programmable data processing device, a device is generated that implements the functions / actions specified in one or more blocks in the flowchart and / or block diagram. These computer-readable program instructions can also be stored in a computer-readable storage medium, where these instructions cause the computer, programmable data processing device, and / or other device to operate in a specific manner. Thus, the computer-readable medium storing the instructions comprises an article of manufacture that includes instructions for implementing various aspects of the functions / actions specified in one or more blocks in the flowchart and / or block diagram.

[0053] Computer-readable program instructions may also be loaded onto a computer, other programmable data processing apparatus, or other device, so that a series of operational steps are performed on the computer, other programmable data processing apparatus, or other device to produce a computer-implemented process, thereby causing the instructions executed on the computer, other programmable data processing apparatus, or other device to implement the functions / actions specified in one or more blocks in the flowchart and / or block diagram.

[0054] The flowcharts and block diagrams in the accompanying drawings show the possible implementation architecture, functions and operations of the systems, methods and computer program products according to multiple embodiments of the present invention. In this regard, each box in the flowchart or block diagram can represent a module, program segment or part of an instruction, and the module, program segment or part of the instruction contains one or more executable instructions for implementing the specified logical function. In some alternative implementations, the functions marked in the box can also occur in an order different from that marked in the accompanying drawings. For example, two consecutive boxes can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, depending on the functions involved. It should also be noted that each box in the block diagram and / or flowchart, and the combination of boxes in the block diagram and / or flowchart, can be implemented by a dedicated hardware-based system that performs the specified function or action, or can be implemented by a combination of dedicated hardware and computer instructions. It is well known to those skilled in the art that implementation by hardware, implementation by software, and implementation by a combination of software and hardware are all equivalent.

[0055] While various embodiments of the present invention have been described above, the foregoing description is intended to be illustrative, non-exhaustive, and not limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments. The terminology used herein is selected to best explain the principles of the embodiments, their practical applications, or technological improvements in the marketplace, or to enable others skilled in the art to understand the embodiments disclosed herein. The scope of the present invention is defined by the appended claims.

Claims

1. A method for controlling the pressing force of a robotic arm based on a pulse wave signal, comprising the following steps: Collect the pulse wave signal of the target; Obtain the interaction force between the end of the robotic arm and the target, and determine the desired pressing force according to the mapping relationship between the pressing effect and the pulse wave signal; Establish an admittance control model to convert the desired pressing force into the desired trajectory of the robotic arm; Based on the error between the actual trajectory and the desired trajectory of the robotic arm, use a PID controller to determine the control amount for the subsequent movement of the robotic arm to achieve tracking of the desired trajectory.

2. The method according to claim 1, wherein, The admittance control model is expressed as: Among them, X r is the initial desired trajectory of the robotic arm, X is the new desired trajectory of the robotic arm, F r is the desired pressing force of the robotic arm, F e is the interaction force between the end of the robotic arm and the target, M d is the inertia matrix, B d is the damping matrix, K d is the stiffness matrix.

3. The method according to claim 1, wherein, The PID controller is expressed as: e(t) = x(t) - y(t) where e(t) is the error between the input x(t) and the output y(t), u(t) is the control quantity output to the robotic arm, K p is the proportional parameter, K i is the integral parameter, K d is the differential parameter, and a and b are the lower and upper limits of integration, respectively.

4. The method according to claim 1, wherein, The interaction force between the end of the robotic arm and the target is obtained by using a flexible pressure array sensor provided at the end of the robotic arm.

5. The method according to claim 1, wherein, The pulse wave signal is obtained by using a pulse wave measurement sensor provided at the end of the limb on the same side as the target.

6. The method according to claim 1, wherein, The tracking of the desired trajectory is achieved according to the following steps: Take the trajectory change amount obtained by the admittance control model as the trajectory change amount of the robotic arm in the task space, and use the inverse kinematics model of the robotic arm to convert the new trajectory into the motor joint angle values corresponding to the respective joints of the robotic arm, and obtain the actual joint angles via the encoders on the joints; Use the PID controller to make the robotic arm reach the target position, and the interaction force generated with the environment is also reacted back to the admittance controller to form a double closed-loop control to achieve tracking of the desired trajectory.

7. The method according to claim 1, wherein, The pressing effect is the pressing hemostasis effect, and there is a mapping relationship between the pressing hemostasis effect and the ratio of the amplitude of the pulse wave signal in the pressing state to the amplitude of the normal pulse wave signal.

8. A system for controlling the pressing force of a robotic arm based on a pulse wave signal, comprising a signal acquisition and processing module, an admittance control model, a PID controller, and a robotic arm, wherein: The signal acquisition and processing module is used to collect the pulse wave signal of the target, obtain the interaction force between the end of the robotic arm and the target, and then determine the desired pressing force according to the mapping relationship between the pressing effect and the pulse wave signal; The admittance control model is used to convert the desired pressing force into the desired trajectory of the robotic arm; The PID controller is used to determine the control amount for the subsequent movement of the robotic arm based on the error between the actual trajectory and the desired trajectory of the robotic arm to achieve tracking of the desired trajectory.

9. A computer-readable storage medium, on which a computer program is stored, wherein, When the computer program is executed by a processor, it implements the steps of the method according to any one of claims 1 to 7.

10. A computer device, comprising a memory and a processor, and a computer program capable of running on the processor is stored on the memory, wherein, When the processor executes the computer program, it implements the steps of the method according to any one of claims 1 to 7.

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