Control method and control device for cart of medical mechanical arm system and cart

Abstract

The invention provides a control method and device for a cart of a medical mechanical arm system and the cart. The cart comprises a motor. The control method comprises the steps that the expected displacement of the cart at the current moment is converted into driving force at the current moment; according to the driving force and the speed of the cart at the previous moment, the expected speed of the cart at the current moment is determined; according to the expected speed, a motor of the cart is controlled to output corresponding torque, and the cart is driven to move. According to the control method, the cart of the medical mechanical arm system can be controlled more smoothly, vibration of the cart is reduced in the control process, the response speed is increased, and better somatosensory control experience is provided for a user.

Description

Technical Field

[0001] The present application relates to the technical field of electromechanical control, and particularly to a control method, a control device and a trolley for a trolley of a medical robotic arm system. Background Art

[0002] In a remote surgery system, there are usually two main devices: a patient-side robot trolley and a doctor-side trolley. In an actual application scenario, if it is necessary to move the patient-side trolley to a specific position, the operator holds the handle of the patient-side trolley and directly applies an operating force to the handle. The force sensor installed on the handle of the patient-side trolley detects the magnitude and direction of the force applied by the operator, and then the control system processor generates a speed command according to the conversion algorithm between force and speed, and further controls the servo motor of the drive wheel of the patient-side trolley to output torque and speed, driving the forward and backward movement or turning of the patient-side trolley. This speed closed-loop control system does not have a direct position closed-loop control, and it is difficult for the operator to accurately stop at the target position. Moreover, when the force sensor drifts, speed will be generated without actual thrust. When the operator tightly holds the handle, the vehicle body will drive the handle to vibrate under the action of noise, and the vibration will generate additional force sensing information input to the controller, resulting in divergent vibration and causing the trolley to vibrate violently and get out of control. Similarly, the trolley is also prone to violent vibration when passing over ditches and bumps. In addition, the force-velocity linear control lacks flexibility, making the operator feel that the operation process is relatively "stiff". When the trolley is pushed by an impact force, the trolley has no compliance, which is not conducive to the comfortable feeling of the human body. Summary of the Invention

[0003] The present application provides a control method, a control device and a trolley for a trolley of a medical robotic arm system, with compliant control and fast response.

[0004] The present application provides a control method for a trolley of a medical robotic arm system, the trolley including a motor, and the control method includes:

[0005] Converting the desired displacement of the trolley at the current moment into a driving force at the current moment;

[0006] Determining the desired speed of the trolley at the current moment according to the driving force and the speed of the trolley at the previous moment;

[0007] Controlling the motor of the trolley to output a corresponding torque according to the desired speed to drive the trolley to move.

[0008] Optionally, after determining the desired speed of the trolley at the current moment, the method includes:

[0009] Determining the actual displacement of the trolley according to the desired speed;

[0010] Determine the desired displacement of the trolley at the next moment according to the desired displacement and the actual displacement at the current moment.

[0011] Optionally, the determining the desired displacement of the trolley at the next moment according to the desired displacement and the actual displacement at the current moment includes:

[0012] Calculate the difference between the desired displacement at the current moment and the actual displacement, and control the magnitude of the driving force in real time according to the difference, so as to determine the desired displacement of the trolley at the next moment.

[0013] Optionally, the determining the actual displacement of the trolley according to the desired speed includes:

[0014] Determine the actual displacement of the trolley through an integration link.

[0015] Optionally, the converting the desired displacement of the trolley at the current moment into the driving force at the current moment includes:

[0016] The desired displacement of the trolley at the current moment is converted into the driving force at the current moment through conversion and transfer function calculation.

[0017] Optionally, the determining the desired speed of the trolley at the current moment according to the driving force and the speed of the trolley at the previous moment includes:

[0018] Substitute the driving force and the speed of the trolley at the previous moment into the admittance control model of the trolley to obtain the desired speed of the trolley at the current moment.

[0019] Optionally, the admittance control model is obtained in the following manner:

[0020] Determine the admittance system model of the driving force and speed of the trolley;

[0021] Perform Laplace transform on the admittance system model to obtain the transfer function of the driving force and speed of the trolley;

[0022] Convert the transfer function into a difference equation to obtain the admittance control model.

[0023] Optionally, the parameters of the admittance system model include inertia parameters and damping parameters, and the determining the admittance system model of the driving force and speed of the trolley includes:

[0024] Determine the admittance system model of the driving force and speed of the trolley according to the inertia parameters and the damping parameters.

[0025] Optionally, the parameters of the admittance system model include a stiffness parameter, and the value of the stiffness parameter is determined according to the inertia parameter and the damping parameter.

[0026] The present application provides a control device for a cart of a medical robotic arm system. The cart includes a motor, and the control device includes:

[0027] A displacement conversion force module, configured to convert the desired displacement of the cart at the current moment into a driving force at the current moment;

[0028] A speed calculation module, configured to determine the desired speed of the cart at the current moment according to the driving force and the speed of the cart at the previous moment;

[0029] A torque control module, configured to control the motor of the cart to output a corresponding torque according to the desired speed, so as to drive the cart to move.

[0030] The present application further provides a cart of a medical robotic arm system, including:

[0031] A motor; and

[0032] The control device of the cart as described above, connected to the motor.

[0033] The present application further provides a computer-readable storage medium, on which a program is stored. When the program is executed by a processor, it implements the control method for the cart of the medical robotic arm system described in any one of the above.

[0034] In some embodiments, converting the desired displacement of the cart at the current moment into a driving force at the current moment; determining the desired speed of the cart at the current moment according to the driving force and the speed of the cart at the previous moment; controlling the motor of the cart to output a corresponding torque according to the desired speed, and driving the cart to move, so that the cart can be more compliant in controlling the cart of the medical robotic arm system, reducing the vibration of the cart during the control process, improving the response speed, and providing a better somatosensory control experience for the user.

[0035] It should be understood that the above general description and the following detailed description are only exemplary and explanatory, and cannot limit the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] The drawings herein are incorporated into the specification and form a part of the specification, showing embodiments consistent with the present application, and are used together with the specification to explain the principles of the present application.

[0037] Figure 1 The structural schematic diagram of an embodiment of the medical robot of the present application is shown.

[0038] Figure 2Shown as Figure 1 The structural schematic diagram of another embodiment of the medical robotic arm system shown in

[0039] Figure 3 The flowchart of an embodiment of the control method of the cart of the medical robotic arm system of the present application is shown.

[0040] Figure 4 The control block diagram of an embodiment of the control device of the present application is shown.

[0041] Figure 5 The control block diagram of another embodiment of the control device of the present application is shown.

[0042] Figure 6 The module block diagram of an embodiment of the control device of the cart of the medical robotic arm system of the present application is shown.

[0043] Figure 7 The module block diagram of another embodiment of the control device of the present application is shown.

[0044] Figure 8 The structural schematic diagram of the simulation cart system of the embodiment of the present application is shown.

[0045] Figure 9 Shown as Figure 8 Another structural schematic diagram of the simulation cart system shown in

[0046] Figure 10 Shown as Figure 8 The control block diagram of the simulation cart system shown in

[0047] Figure 11 The displacement schematic diagram of the cart and the human hand under the conditions of stiffness parameter 2000N / m and damping parameter 400.

[0048] Figure 12 For Figure 11 The displacement error schematic diagram of the cart and the human hand.

[0049] Figure 13 The displacement schematic diagram of the cart and the human hand under the conditions of stiffness parameter 1000N / m and damping parameter 400.

[0050] Figure 14 For Figure 13 The displacement error schematic diagram of the cart and the human hand. Specific embodiments

[0051] Exemplary embodiments will be described in detail herein, and examples thereof are shown in the accompanying drawings. When the following description refers to the accompanying drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present application. On the contrary, they are merely examples of devices and methods consistent with some aspects of the present application as detailed in the appended claims.

[0052] The terms used in the present application are for the purpose of describing specific embodiments only and are not intended to limit the present application. Unless otherwise defined, the technical terms or scientific terms used in the present application should have the ordinary meanings understood by those of ordinary skill in the art to which the present application pertains. The terms "first", "second" and similar terms used in the specification and claims of the present application do not denote any order, quantity or importance, but are only used to distinguish different components. Similarly, the terms such as "a" or "an" do not denote a limitation of quantity, but mean that there is at least one. "Plurality" or "several" means two or more. Unless otherwise specified, terms such as "front", "rear", "lower" and / or "upper" are for convenience of description only and are not limited to a position or a spatial orientation. The terms such as "comprising" or "including" mean that the elements or items appearing before "comprising" or "including" cover the elements or items listed after "comprising" or "including" and their equivalents, and do not exclude other elements or items. The terms such as "connected" or "coupled" are not limited to physical or mechanical connections, and may include electrical connections, whether direct or indirect.

[0053] The terms used in the present application are for the purpose of describing specific embodiments only and are not intended to limit the present application. The singular forms "a", "the" and "said" used in the present application and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the term "and / or" as used herein refers to and includes any and all possible combinations of one or more of the associated listed items.

[0054] The trolley of the embodiment of the present application includes a motor. The control method includes: converting the desired displacement of the trolley at the current moment into the driving force at the current moment; determining the desired speed of the trolley at the current moment according to the driving force and the speed of the trolley at the previous moment; and controlling the motor of the trolley to output a corresponding torque according to the desired speed to drive the trolley to move. The present application can control the trolley of the medical robotic arm system more smoothly, reduce the vibration of the trolley during the control process, improve the response speed, and provide a better somatosensory control experience for the user.

[0055] The present application provides a control method, a control device and a trolley for a trolley of a medical robotic arm system. The control method, the control device and the trolley for the trolley of the medical robotic arm system of the present application will be described in detail below with reference to the accompanying drawings. Without conflict, the features in the following embodiments and implementation manners can be combined with each other.

[0056] Figure 1 The following shows a schematic structural diagram of an embodiment of a medical robot 10 of the present application. As Figure 1 shown, the medical robot 10 includes a control system 11, an imaging system 12 and a medical robotic arm system 13.

[0057] The control system 11 has a display unit for displaying the surgical instrument environment, a doctor operation control mechanism, an armrest, etc. Among them, an observation window is opened on the display unit for the doctor to observe. The operation control mechanism is configured such that its movement can correspond to the movement of the surgical instrument. The armrest is used to place the doctor's arm. In addition, on the doctor's console, there are also other control switches that are convenient for the hands or feet to touch or press, used for various function operations to complete human-machine interaction.

[0058] The imaging system 12 has a display screen, an endoscope controller, system electronic equipment, an image processor, etc.

[0059] The medical robotic arm system 13 may include at least one robotic arm 131. The robotic arm 131 has a plurality of connecting arms. Adjacent two connecting arms move relative to each other with a specific degree of freedom, so that the end of the robotic arm 131 can achieve multi-degree-of-freedom movement (such as 7 degrees of freedom, which varies according to different surgical instruments).

[0060] Figure 2 The following shows Figure 1 a schematic structural diagram of another embodiment of the medical robotic arm system 13 shown.

[0061] The medical robotic arm system 13 includes a trolley 20. The trolley 20 includes a base 21. A column 22 is provided on the base 21, and at least one robotic arm 131 that can move up and down relative to the base 21 is provided on the column 22. A handle 23 may also be provided on the base 21, and an operator can assist in moving the base 21 through the handle 23.

[0062] Refer to Figures 1 to 2, the robotic arm 131 generally may include an adjustment arm 132 and an operating arm 133. The end of the operating arm 133 is used to install an instrument support frame 134, and the instrument support frame 134 is used to install surgical instruments or endoscopes. An instrument driving device may also be provided on the instrument support frame 134 to drive the surgical instruments to perform actions such as insertion and clamping. Before operating the robot for surgery, it is necessary to first operate the adjustment arm 132 so that the surgical instrument installed at the end of the operating arm 133 reaches the designated position, and then lock the rotating joints of the adjustment arm 132. During the surgery, the surgical operation is completed by remotely controlling the operating arm 133, while keeping the rotating joints of the adjustment arm 132 locked to prevent relative rotation between the connecting rods (i.e., connecting arms) of the adjustment arm 132 during the surgery.

[0063] The cart 20 of the medical robotic arm system includes a motor 25 and the control device 24 of the cart provided in this application. The control device 24 of the cart is connected to the motor 25 and is used to control the motor 25 to drive the cart 20 to move.

[0064] Figure 3 The flowchart of an embodiment of the control method 30 of the cart of the medical robotic arm system provided in this application is shown. The control device 24 is used to execute the control method 30 of this application. Figure 4 The control block diagram of an embodiment of the control device 24 provided in this application is shown.

[0065] The control method 30 includes: step 31 to step 33.

[0066] Step 31, convert the desired displacement of the cart 20 at the current moment into the driving force at the current moment.

[0067] The desired displacement of the cart 20 at the current moment may be equal to the displacement of the operator's hand relative to the ground at the current moment. Converting the desired displacement into the driving force can eliminate the need to measure the driving force applied by the operator's hand.

[0068] In some embodiments, step 31 includes: the desired displacement of the cart 20 at the current moment is converted into the driving force received by the cart 20 at the current moment through conversion and transfer function conversion.

[0069] Reference Figure 4 , X d is the desired displacement of the cart 20 at the current moment. X d After passing through the conversion coefficient K and the transfer function conversion, it is converted into the driving force F(t) received by the cart 20 at the current moment.

[0070] Step 32, determine the desired speed of the cart 20 at the current moment according to the driving force and the speed of the cart 20 at the previous moment.

[0071] According to the driving force F(t) and the speed V(t - 1) of the trolley 20 at the previous moment, determine the expected speed V(t) of the trolley 20 at the current moment. The expected speed of the trolley 20 at the current moment is obtained based on the speed of the trolley 20 at the previous moment and the driving force, and the driving force is obtained from the expected displacement at the current moment. In this way, the trolley 20 can be controlled only based on the expected displacement and speed, converting the dynamic problem into a position control problem, so that the trolley 20 is not affected by external forces.

[0072] Step 33: Control the motor 25 of the trolley 20 to output a corresponding torque according to the expected speed to drive the trolley 20 to move.

[0073] In some embodiments, convert the expected displacement of the trolley 20 at the current moment into the driving force at the current moment; according to the driving force and the speed of the trolley 20 at the previous moment, determine the expected speed of the trolley 20 at the current moment; according to the expected speed, control the motor 25 of the trolley 20 to output a corresponding torque to drive the trolley 20 to move. By position control, the trolley 20 can be made to be in the expected position, and the trolley 20 of the medical robotic arm system can be controlled more smoothly, reducing the vibration of the trolley 20 during the control process, improving the response speed, and providing a better somatosensory control experience for the user.

[0074] In some embodiments, step 32 includes: substituting the driving force and the speed of the trolley 20 at the previous moment into the admittance control model of the trolley 20 to obtain the expected speed of the trolley 20 at the current moment.

[0075] In some embodiments, the admittance control model is obtained in the following manner: determine the admittance system model of the driving force and speed of the trolley 20; perform a Laplace transform on the admittance system model to obtain the transfer function of the driving force and speed of the trolley 20; convert the transfer function into a difference equation to obtain the admittance control model.

[0076] In some embodiments, the parameters of the admittance system model include inertia parameters and damping parameters, and the control method 30 includes: determining the admittance system model of the driving force and speed of the trolley 20 according to the inertia parameters and damping parameters.

[0077] In some embodiments, the parameters of the admittance system model include stiffness parameters, and the value of the stiffness parameter is determined according to the inertia parameters and damping parameters.

[0078] In this application, through position control, the movement trajectory of the trolley follows the movement trajectory of the operator's hand relative to the ground. The admittance control model of the driving force and speed of the trolley 20 is set as:

[0079]

[0080] where F is the driving force, M is the inertia parameter, and B is the damping parameter. is the acceleration; is the velocity.

[0081] Taking the Laplace transform of Equation (1), we get:

[0082]

[0083] Reconstructing the above admittance control model with the velocity variable, we get:

[0084]

[0085] where v is the velocity of the cart 20.

[0086] Taking the Laplace transform of Equation (3), we get:

[0087]

[0088] Regarding Equation (4) as a first-order inertia link, we get

[0089]

[0090]

[0091] where k is the proportionality coefficient and τ is the time constant. By adjusting the inertia parameter M and the damping parameter B, the performance of this first-order inertia link can be changed, and thus the compliance of this model can be adjusted.

[0092] Figure 5 The control block diagram of another embodiment of the control device 24 of the present application is shown. In Figure 5 the embodiment shown, the transfer function is Equation (6),

[0093]

[0094] where X is the actual displacement of the cart 20, X d is the desired displacement of the cart 20, K is the stiffness parameter, M is the inertia parameter, B is the damping parameter, and T is the time constant.

[0095] The characteristic equation is Equation (7),

[0096] D(s) = MTs 3 +(M + BT)s 2 + Bs + K (7)

[0097] To make the admittance system stable, according to the algebraic stability criterion, Equation (7) needs to have a negative real part. By restricting the coefficients of the characteristic equation and the coefficients of the Routh table, we get Equation (8),

[0098] TB 2 + MB - MTK > 0 (8)

[0099] It can be obtained therefrom that, in order to stabilize the admittance system, the stiffness parameter K needs to satisfy Equation (9).

[0100]

[0101] Taking the inverse Laplace transform of Equation (4) and using a difference equation to replace the differential equation, Equation (10) is obtained:

[0102]

[0103] Equation (10) is the admittance control model.

[0104] In some embodiments, after step 32, the control method 30 includes: determining the actual displacement of the cart 20 according to the desired speed; determining the desired displacement of the cart 20 at the next moment according to the desired displacement and the actual displacement at the current moment.

[0105] In some embodiments, the control method 30 further includes: determining the actual displacement of the cart 20 through an integral link.

[0106] Referring to Figure 4 , the driving force F(t) passes through the admittance control link, is converted into the speed V(t) of the cart 20, and then passes through the integral link to be converted into the actual displacement X(t) of the cart 20.

[0107] In some embodiments, the control method 30 further includes: calculating the difference between the desired displacement and the actual displacement at the current moment, and controlling the magnitude of the driving force in real time according to the difference, so as to determine the desired displacement of the cart 20 at the next moment.

[0108] The actual displacement X(t) of the cart 20 serves as the system negative feedback, calculates the difference with the desired displacement X d , and then controls the driving force F(t) to control the desired displacement of the cart 20 at the next moment, forming a closed-loop admittance control system.

[0109] Figure 6 The block diagram of an embodiment of the control device 24 of the cart of the medical robotic arm system provided by the present application is shown. The control device 24 includes: a displacement conversion force module 241, a speed calculation module 242, and a torque control module 243.

[0110] The displacement conversion force module 241 is used to convert the desired displacement of the cart 20 at the current moment into the driving force at the current moment.

[0111] The speed calculation module 242 is used to determine the desired speed of the cart 20 at the current moment according to the driving force and the speed of the cart 20 at the previous moment.

[0112] The torque control module 243 is configured to control the motor 25 of the trolley 20 to output a corresponding torque according to the desired speed, so as to drive the trolley 20 to move.

[0113] Figure 7 The block diagram of another embodiment of the control device 24 provided by the present application is shown.

[0114] As Figure 7 shown, the control device 24 includes one or more processors 41, which are configured to implement the control method 30 as described above.

[0115] In some embodiments, the control device 24 may include a computer-readable storage medium 42. The computer-readable storage medium 42 may store a program that can be called by the processor 41, and may include a non-volatile storage medium. In some embodiments, the control device 24 may include a memory 43 and an interface 44. In some embodiments, the control device 24 may further include other hardware according to actual applications.

[0116] The present application also provides a computer-readable storage medium, on which a computer program is stored. When the program is executed by a processor, it implements the control method 30 as described above. The computer-readable medium includes permanent and non-permanent, removable and non-removable media, and information storage can be implemented by any method or technology. The information may be computer-readable instructions, data structures, program modules, or other data. Examples of computer storage media include, but are not limited to, phase change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technologies, compact disc read-only memory (CD-ROM), digital versatile disc (DVD) or other optical storage, magnetic cassette tapes, magnetic disk storage or other magnetic storage devices, or any other non-transmission medium that can be used to store information accessible by a computing device.

[0117] Next, the present application will be further described through simulation.

[0118] Figure 8 The structural schematic diagram of the simulation trolley system according to the embodiment of the present application is shown.

[0119] Among them, the self-weight of the trolley M = 800 kg. The outer ring of the large wheels of the trolley is made of rubber material, and the density is 1.1 kg / m 3 The passive wheels of the trolley are made of steel material, and the density is 7.8×10 3 kg / m 3 .

[0120] Based on the above boundary conditions, a simplified model of the trolley movement simulation was established in the simulation software, including the vehicle body 51, large wheels 52, passive wheels 53, sliders 54, handles 55, the ground 56, and the human hand model 57.

[0121] In the dynamic simulation environment, contact forces were added to the large wheels 52, passive wheels 53 of the trolley and the ground 56, with a stiffness of 2.566×10 8 N / m, a damping coefficient of 570, and a penetration depth of 0.1 mm. Contact forces were added between the slider 54, the handle 55 and the vehicle body 51, with a stiffness of 1.0×10 8 N / m and a damping coefficient of 1.0×10 4 . A contact force was added between the human hand model 57 and the handle 55, with a stiffness of 1.0×10 8 N / m and a damping coefficient of 1.0×10 4 .

[0122] In terms of kinematic pairs, there are rotational pairs around the wheel axis between the vehicle body 51 and the large wheels 52, passive wheels 53. There are translational pairs between the slider 54 and the vehicle body 51, the slider 54 and the handle 55, and the human hand model 57 and the ground 56, with the directions as shown in the figure. Springs 58 and 59 were added between the sensor position of the vehicle body 51 and the slider 54, and between the slider 54 and the handle 55 respectively, and their variables are the stiffness coefficient and damping coefficient, as Figure 9 shown.

[0123] A control model was built in the simulation environment. A world coordinate system for the trolley movement was established with the forward direction of the trolley as the Y-axis and the direction of the vertical ground as the X-axis. In terms of driving, the translational pair between the human hand model 57 and the ground 56 was set as a mobile drive, and at the same time, a torque was added to the large wheel 52 along the axis direction of the large wheel 52 of the trolley, which together served as the input of the simulation system. Taking the measured values of the velocity and acceleration of the center of mass of the vehicle body 51 in the Y-axis direction in the world coordinate system and the amplitude measurement value of the spring 58 along its translational pair direction as the output, a motion system of the trolley movement input and output was established. The control system block diagram is as Figure 10 shown.

[0124] In a control system such as Figure 10 , Input 1 and Input 2 are the displacement amounts of the human hand model 57 relative to the ground 56, and Input 3 and Input 4 are the torque values received by the driving wheels of the base trolley in the admittance control link. Output 1 is the velocity of the trolley in the forward direction, which is fed back as a negative feedback to the displacement control adjustment (PID adjustment) in the admittance control link. Output 2 is the relative displacement amount detected by the tension and compression sensor between the vehicle body 51 and the handle 55, which is fed back as a negative feedback to the admittance control link to realize the adjustment of the torque magnitude received by the driving wheels of the trolley.

[0125] Figure 11 It is a schematic diagram of the displacements of the trolley and the human hand under the conditions of a stiffness parameter of 2000 N / m and a damping parameter of 400. Figure 12 For Figure 11 It is a schematic diagram of the displacement error of the trolley and the human hand.

[0126] Figure 13 It is a schematic diagram of the displacements of the trolley and the human hand under the conditions of a stiffness parameter of 1000 N / m and a damping parameter of 400. Figure 14 For Figure 13 It is a schematic diagram of the displacement error of the trolley and the human hand.

[0127] In the control system, a sine wave with an input amplitude of 10 cm and a period T = 2 s is input. The sensor stiffness K of the control system is changed to 2000 N / m and 10000 N / m respectively, and the damping parameters B of the system are 300, 400, and 500 respectively. From Figures 10 to 13 it can be seen that when the stiffness is 10000 N / m and the damping parameter is 400 (i.e., when K = 10000 and 1 / (Ts + 1) = 1 / (3s + 400)), the trajectory following effect of the human hand displacement and the trolley displacement is smoother than that when the stiffness is 2000 N / m and the damping parameter is 400, and its average error is 1.7 mm.

[0128] After considering the specification and practicing the application disclosed herein, those skilled in the art will readily conceive of other embodiments of the present application. The present application is intended to cover any variations, uses, or adaptations of the present application, which follow the general principles of the present application and include the common general knowledge or conventional technical means in the technical field not disclosed in the present application. The specification and examples are only regarded as exemplary, and the true scope and spirit of the present application are pointed out by the following claims.

[0129] It should be understood that the present application is not limited to the exact structures described above and shown in the drawings, and various modifications and changes can be made without departing from its scope. The scope of the present application is only limited by the appended claims.

Claims

1. A control method for a cart of a medical robotic arm system, characterized in that, The trolley includes a motor, and the control method includes: Converting the expected displacement of the trolley at the current moment into the driving force at the current moment; Determining the expected speed of the trolley at the current moment according to the driving force and the speed of the trolley at the previous moment; Controlling the motor of the trolley to output a corresponding torque according to the expected speed to drive the trolley to move.

2. The control method of the cart of the medical robotic arm system according to claim 1, wherein After determining the expected speed of the trolley at the current moment, the method includes: Determining the actual displacement of the trolley according to the expected speed; Determining the expected displacement of the trolley at the next moment according to the expected displacement at the current moment and the actual displacement.

3. The control method of the cart of the medical robotic arm system according to claim 2, wherein, The determining the expected displacement of the trolley at the next moment according to the expected displacement at the current moment and the actual displacement includes: Calculating the difference between the expected displacement at the current moment and the actual displacement, and controlling the magnitude of the driving force in real time according to the difference, so as to determine the expected displacement of the trolley at the next moment.

4. The control method of the cart of the medical robotic arm system according to claim 2, wherein The determining the actual displacement of the trolley according to the expected speed includes: Determining the actual displacement of the trolley through an integral link.

5. The control method of the cart of the medical robotic arm system according to claim 1, characterized in that, The converting the expected displacement of the trolley at the current moment into the driving force at the current moment includes: The expected displacement of the trolley at the current moment is converted into the driving force at the current moment through conversion and transfer function conversion.

6. The control method of the cart of the medical robotic arm system according to claim 1, characterized in that, The determining the expected speed of the trolley at the current moment according to the driving force and the speed of the trolley at the previous moment includes: Substituting the driving force and the speed of the trolley at the previous moment into the admittance control model of the trolley to obtain the expected speed of the trolley at the current moment.

7. The control method of the trolley of the medical robotic arm system according to claim 6, wherein, The admittance control model is obtained through the following method: Determining the admittance system model of the driving force and speed of the trolley; Performing Laplace transform on the admittance system model to obtain the transfer function of the driving force and speed of the trolley; Converting the transfer function into a difference equation to obtain the admittance control model.

8. The control method of the cart of the medical robotic arm system according to claim 7, characterized in that, The parameters of the admittance system model include inertia parameters and damping parameters, and the determining the admittance system model of the driving force and speed of the trolley includes: Determining the admittance system model of the driving force and speed of the trolley according to the inertia parameters and the damping parameters.

9. The control method of the cart of the medical robotic arm system according to claim 8, characterized in that, The parameters of the admittance system model include stiffness parameters, and the value of the stiffness parameter is determined according to the inertia parameters and the damping parameters.

10. A control device for a cart of a medical robotic arm system, characterized in that, The trolley includes a motor, and the control device includes: A displacement conversion force module for converting the expected displacement of the trolley at the current moment into the driving force at the current moment; A speed calculation module for determining the expected speed of the trolley at the current moment according to the driving force and the speed of the trolley at the previous moment; A torque control module for controlling the motor of the trolley to output a corresponding torque according to the expected speed to drive the trolley to move.

11. A trolley of a medical robotic arm system, characterized in that, Including: A motor; And The control device of the trolley as described in claim 10 is connected to the motor.

12. A computer-readable storage medium, characterized in that, A program is stored thereon, and when the program is executed by a processor, it implements the control method of the trolley of the medical robotic arm system as described in any one of claims 1-9.

Images