A sensorless force sensing method and system for an incision continuum manipulator

Abstract

The present invention relates to the technical field of surgical operating arms, and specifically discloses a sensorless force sensing method and system for an incision continuum operating arm, the method comprising: analyzing the cable tension transmission relationship to obtain the cable tension distribution inside each deformation unit; performing static analysis on the incision continuum operating arm, and establishing a static model of the incision continuum operating arm using a beam constraint model; introducing the relationship between the cable variation and the deformation parameter of the incision continuum operating arm into the static model as a constraint equation; obtaining the cable variation and cable tension during the movement of the incision continuum operating arm, and obtaining the interaction force at the end of the continuum operating arm through iterative calculation based on the cable tension distribution, static model and constraint equation. The present invention can realize the accurate perception of the interaction force between the continuum operating arm and the external environment, and realizes the accurate perception of the interaction force between the incision continuum operating arm and the external environment.

Description

Technical Field

[0001] This invention relates to the field of surgical operating arm technology, and in particular to a sensorless force sensing method and system for an incision continuum operating arm. Background Technology

[0002] The statements in this section are merely background information related to the present invention and do not necessarily constitute prior art.

[0003] The incision continuous manipulator is manufactured by machining a series of notches inside a hollow nickel-titanium alloy cylindrical tube. The incision continuous manipulator is cable-driven; typically, axial holes are drilled in the wall of the hollow nickel-titanium alloy cylindrical tube to form wire guide holes, through which the cables pass and are fixed to the incision continuous manipulator. Pulling multiple cables deforms the incision continuous manipulator, thus achieving its movement. Due to its compact size and excellent mechanical properties, the incision continuous manipulator is widely used in the design of minimally invasive surgical manipulators. In the application of surgical manipulators, accurately sensing the interaction force between the continuous manipulator and the external environment is crucial. For example, when the continuous manipulator and clamps dissect soft tissue in the lesion area, excessive interaction force may tear soft tissue outside the lesion area, causing unnecessary damage to the patient. Sensing the interaction force provides effective feedback to limit its magnitude and improve surgical safety.

[0004] Traditional force sensing methods typically require sensors integrated into a continuous manipulator to acquire relevant data. However, in the limited surgical environment, integrating sensors into the incision continuous manipulator not only increases the cost and complexity of the continuous manipulator, but may also be affected by the sensor performance, leading to a decrease in the accuracy of force sensing. Summary of the Invention

[0005] To address the aforementioned issues, this invention proposes a sensorless force sensing method and system for a cut continuum manipulator. An accurate static model of the cut continuum manipulator is established, and cable variation is introduced as a constraint into the static model, thereby achieving sensorless force sensing.

[0006] In some implementations, the following technical solutions are adopted:

[0007] A sensorless force sensing method for a slit continuum manipulator includes:

[0008] By analyzing the cable tension transmission relationship, the cable tension distribution inside each deformation unit is obtained;

[0009] Static analysis was performed on the cut continuum manipulator, and a static model of the cut continuum manipulator was established using a beam constraint model.

[0010] The relationship between cable variation and the deformation parameters of the cut continuum manipulator is introduced into the static model as a constraint equation;

[0011] The cable variation and cable tension during the movement of the continuous manipulator are obtained. Based on the cable tension distribution, static model and constraint equations, the interaction force at the end of the continuous manipulator is obtained through iterative calculation.

[0012] As an optional solution, the tension transmission relationship of the cables within each deformation unit is as follows:

[0013] ;

[0014] in, This represents the tension on the i-th cable in part a of the (n+1)-th segment of the slit continuum. This represents the tension on the i-th cable in part b of the n-th segment of the cut continuum. This represents the tension on the i-th cable in part a of the n-th segment of the cut continuum; , , These are all tension transmission coefficients. The deflection angle of the beam in section b of the nth segment of the continuous cutting manipulator. The deflection angle of the beam in section a of segment n of the continuous cutting manipulator arm. Let be the deflection angle of the (n+1)th segment a of the beam of the cut continuum manipulator.

[0015] As an optional approach, a static analysis is performed on the cutting continuum manipulator to establish a force analysis model for the ends of each beam of the cutting continuum manipulator, specifically:

[0016] ;

[0017] ;

[0018] ;

[0019] ;

[0020] in, and These are the force and moment applied to the end of beam section a, respectively. and This represents the force and moment applied to the end of beam section b; In the local coordinate system The tension on part a of the cable in the nth segment of the lower cut continuum. In the local coordinate system The tension on the cable in section b of the nth segment of the lower cut continuum; Indicates the end load force of the cut continuum manipulator. In the local coordinate system The expression below, Indicates the end load force of the cut continuum manipulator. In the local coordinate system The expression below; In the local coordinate system The position vector from the end of the beam in section a of the nth segment of the lower cut continuum manipulator to the hole of the i-th cable conductor. In the local coordinate system The position vector from the end of the beam of the nth segment b of the lower cut continuum manipulator to the hole of the i-th cable conductor.

[0021] As an optional solution, the constraint model for the nth compliant mechanism beam is:

[0022] ; ;

[0023] ;

[0024] ;

[0025] in, In the local coordinate system The x-axis component of the dimensionless coordinates of the end of the nth segment (a) of the lower cut continuum manipulator. In the local coordinate system The dimensionless y-axis component of the beam end of the nth segment a part of the lower cut continuum manipulator; In the local coordinate system The x-axis component of the dimensionless coordinates of the end of the beam in section b of the nth segment of the lower cut continuum manipulator. In the local coordinate system The z-axis component of the dimensionless coordinate of the end of the beam in the nth segment b of the lower cut continuum manipulator; The deflection angle of the beam in section b of the nth segment of the continuous cutting manipulator. Let be the deflection angle of the beam in the nth segment a of the cut continuum manipulator; L is the length of the beam, t is the thickness of the beam, and A, B, C, and D are coefficient matrices; , , These are the x and y components of the force and the torque in the z direction that affect the bending of part a, respectively. These are the x and y components of the force and the z-direction torque experienced by part b during bending, respectively.

[0026] As an optional approach, the tension transmission relationship of the cables inside each deformation unit, the force analysis model of the ends of each beam of the cut continuum manipulator, and the constraint model of each compliant mechanism beam are combined to form a static model of the cut continuum manipulator.

[0027] As an optional solution, the relationship between cable variation and deformation parameters of the cutting continuum manipulator is as follows:

[0028] ;

[0029] in, For cable variation, In the local coordinate system The position vector of the guide hole in part a is represented in the figure. The position vector of the guide hole on the guide plate plane where the beam end is located; In the local coordinate system The position vector of the guide hole in part b is represented in the figure. The position vector of the guide hole on the guide plate plane where the beam end is located. Indicates the number of deformable elements.

[0030] As an optional approach, it also includes: considering the interaction force information between the end of the cut continuum manipulator arm and the environment, and adding an equation for the distribution plane at the end of the cut continuum manipulator arm, specifically:

[0031] ;

[0032] in, The direction vector of the load at the end of the manipulator arm of the cut continuum. For the magnitude of the interaction force, The load at the end of the manipulator arm of the cut continuum.

[0033] In other embodiments, the following technical solutions are adopted:

[0034] A sensorless force sensing system for a slit continuum manipulator includes:

[0035] The cable tension analysis module is used to analyze the cable tension transmission relationship and obtain the cable tension distribution inside each deformation unit;

[0036] The static model building module is used to perform static analysis on the cut continuum manipulator, and to build a static model of the cut continuum manipulator using a beam constraint model.

[0037] The constraint equation construction module is used to introduce the relationship between cable variation and the deformation parameters of the cut continuum manipulator into the static model as constraint equations;

[0038] The end-effector interaction force calculation module is used to obtain the cable variation and cable tension during the movement of the continuous manipulator. Based on the cable tension distribution, static model and constraint equations, the interaction force at the end of the continuous manipulator is obtained through iterative calculation.

[0039] In other embodiments, the following technical solutions are adopted:

[0040] A terminal device includes a processor and a memory, the processor being used to implement instructions; the memory being used to store multiple instructions adapted to be loaded by the processor and executed by the sensorless force sensing method of the above-described slit continuum manipulator.

[0041] In other embodiments, the following technical solutions are adopted:

[0042] A computer-readable storage medium storing a plurality of instructions adapted for loading and execution by a processor of a terminal device of the sensorless force sensing method for a cut continuum manipulator described above.

[0043] Compared with the prior art, the beneficial effects of the present invention are:

[0044] (1) The present invention establishes an accurate static model of the cut continuum manipulator, and then introduces the constraint equations of the cable variation and the deformation parameters of the cut continuum manipulator into the static model; based on the cable tension distribution, the static model and the constraint equations, the interaction force at the end of the continuum manipulator can be obtained by iterative calculation; there is no need to integrate sensors on the body of the cut continuum manipulator, only the cable variation and cable tension need to be input, so as to realize the accurate perception of the interaction force between the continuum manipulator and the external environment, and realize the accurate perception of the interaction force between the cut continuum manipulator and the external environment.

[0045] (2) This invention considers the friction model between the wire and the guide hole, and takes into account the influence of external loads. A beam constraint model is used to describe the actual deformation of the flexible beam. Based on the beam constraint model, the actual deformation of the cut continuum manipulator beam is described. Compared with the traditional assumption of constant curvature, that is, assuming that the beam of the cut continuum manipulator bends into a standard arc, the model of this invention is more realistic, improves the accuracy of the model, and thus improves the accuracy of force sensing.

[0046] Other features and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0047] Figure 1 This is a schematic diagram of the overall structure of the slit continuum manipulator in an embodiment of the present invention;

[0048] Figure 2This is a schematic diagram of the deformation unit of the cut continuum manipulator in an embodiment of the present invention;

[0049] Figure 3(a) is a schematic diagram of the cable passing through the wire hole in an embodiment of the present invention;

[0050] Figure 3(b) is a schematic diagram of the force analysis of tension transmission in a single cable in an embodiment of the present invention;

[0051] Figure 4 Force analysis of the entire slit continuum manipulator in this embodiment of the invention;

[0052] Figure 5 Force analysis of the deformation unit of the cut continuum manipulator in this embodiment of the invention;

[0053] Figure 6 This is a dimensional diagram of the deformation unit of the cut continuum manipulator in an embodiment of the present invention;

[0054] Figure 7 This is a schematic diagram of the force on a dimensionless beam in an embodiment of the present invention;

[0055] Figure 8 This is a flowchart of the sensorless force sensing calculation in an embodiment of the present invention;

[0056] Among them, 1-1. Cable, 1-2. Wire reel, 1-3. Beam, 2-1. Wire hole, 2-2. Z-axis bending unit, 2-3. Y-axis bending unit. Detailed Implementation

[0057] It should be noted that the following detailed descriptions are illustrative and intended to provide further explanation of this application. Unless otherwise specified, all technical and scientific terms used in this invention have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains.

[0058] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0059] Example 1

[0060] In one or more embodiments, a sensorless force sensing method for a cut continuum manipulator is disclosed, establishing a static model capable of accurately predicting the deformation of the cut continuum manipulator. This static model considers the deformation of the manipulator in various directions; the deformation shape of the continuum manipulator can be deduced by calculating cable tension. The cable variation is introduced into the static model as a constraint equation, thus obtaining a sensorless force sensing method; this method can calculate the force, i.e., the end effector interaction force, on the cut continuum manipulator by calculating the cable variation and cable tension.

[0061] First, a typical slit continuum manipulator is explained, combined with... Figure 1 The continuous-body cutting manipulator includes cable 1-1, guide reel 1-2, and beam unit 1-3. Beam units are formed at the cut of the continuous-body cutting manipulator, and these beam units are staggered at 90° along the axial direction of the manipulator. The guide reel is fixed to the end of each beam unit and to the beginning of the next beam unit. Cables are installed in guide holes in the continuous-body cutting manipulator, with each cable corresponding to one guide hole.

[0062] Figure 2 This is a schematic diagram of the deformation unit of the cut continuum manipulator, including the wire hole 2-1; in this embodiment, the z-axis bending unit 2-2 of the cut continuum manipulator is part a, and the y-axis bending unit 2-3 of the cut continuum manipulator is part b.

[0063] Combination Figure 8 The method in this embodiment specifically includes the following processes:

[0064] S101: Analyze the cable tension transmission relationship to obtain the cable tension distribution inside each deformation unit.

[0065] This embodiment analyzes the friction between the cable and the conductor reel. For example, Figures 3(a) and 3(b) show the tension transmission when the cable passes through the conductor hole. Figure 3(a) shows a schematic diagram of the cable passing through the conductor hole, and Figure 3(b) shows the force analysis of the tension transmission of a single cable. It is the position of the i-th cable guide hole on the lower surface of the guide plate of the nth segment a part of the cut continuum manipulator; It is the position of the i-th cable wire hole on the upper surface of the wire reel of the nth segment b of the cut continuum manipulator; It is the position of the i-th cable wire hole on the lower surface of the wire reel of the nth segment b of the cut continuum manipulator; It is the position of the i-th cable wire hole on the upper surface of the wire tray of the (n+1)-th segment a of the cut continuum manipulator; It is the supporting force of the cable on the cable at the i-th cable guide hole on the lower surface of the guide plate of the nth segment a part of the cut continuum manipulator; It is the supporting force of the cable on the cable by the i-th cable guide hole on the upper surface of the guide plate of the nth segment b part of the cut continuum manipulator; It is the supporting force of the cable on the cable at the i-th cable guide hole on the lower surface of the guide plate of the nth segment b of the cut continuum manipulator; It is the supporting force of the cable on the cable by the i-th cable guide hole on the upper surface of the guide plate of the (n+1)-th segment a of the cut continuum manipulator. It is the frictional force between the i-th cable wire hole on the upper surface of the wire reel of the nth segment b of the cut continuum manipulator and the cable; It is the supporting force of the cable on the cable at the i-th cable guide hole on the lower surface of the guide plate of the nth segment b part of the cut continuum manipulator; It is the frictional force of the cable on the cable at the i-th cable guide hole on the upper surface of the guide plate of the (n+1)-th segment a of the cut continuum manipulator. It is the tension of the cable outside the cable guide hole of the i-th cable guide plate in the n-th segment a part of the cut continuum manipulator arm; It is the tension of the cable inside the cable guide hole of the guide plate in the nth segment a part of the cut continuum manipulator; It is the tension of the cable outside the cable guide hole of the i-th cable guide plate in the n-th segment b of the cut continuum manipulator; It is the tension of the cable inside the i-th cable guide hole of the guide plate in the n-th segment b of the cut continuum manipulator; It is the tension of the cable outside the cable guide hole of the i-th cable guide hole in the (n+1)-th segment a of the cut continuum manipulator arm.

[0066] In this embodiment, the tension of each part of the cable can be calculated using the following formula:

[0067] (1)

[0068] Combining equation (1), the tension transmission coefficient k is defined as:

[0069] (2)

[0070] By performing the same analysis on other contact points, the tension transmission relationship of the cable can be obtained, as shown in equation (3):

[0071] (3)

[0072] in, It is the coefficient of friction between the cable and the conductor hole. When calculating tension, and It is a known quantity. The tension can be detected by the tension sensor on the drive unit of the cutting continuum manipulator. It needs to be measured in advance, as it is an inherent property of the material. The tension on each segment of the cable of the cut continuum manipulator can be obtained recursively using equation (3).

[0073] S102: Perform static analysis on the cut continuum manipulator and establish a static model of the cut continuum manipulator using a beam constraint model.

[0074] In this embodiment, certain assumptions are made for clearer modeling:

[0075] (1) The cut of the cut continuum manipulator bends only in the plane of symmetry of the two beams;

[0076] (2) Compression and elongation along the axial direction are ignored because the stiffness in this direction is much greater than the stiffness in the bending direction;

[0077] (3) The gravity of the cable and conductor reel is ignored in the cut continuum manipulator, which is much smaller than the tension on the upper cable.

[0078] First, we need to analyze the force distribution within the beam element. Let's take the beam element in section a of segment n as an example. Figure 4 As shown, where, It is the tension of the cable outside the cable guide hole of the i-th cable guide hole in the n-th segment a part of the guide plate of the cut continuum manipulator; It is the local coordinate system of the nth segment a of the incision continuum manipulator. origin of coordinates The center of the circle is located on the upper surface of the disk of the nth segment a of the cut continuum manipulator. The x-axis of the coordinate system is along the axis of the cut continuum manipulator, the y-axis is perpendicular to the plane of symmetry of the flexible beam of segment a, and the z-axis conforms to the direction of the right-hand coordinate system. is the center of the lower surface of the disk in section a of segment n of the cut continuum manipulator; is the local coordinate system of section b of segment n of the cut continuum manipulator. origin of coordinates The center of the circle is located on the upper surface of the disk of the nth segment b of the cut continuum manipulator. The x-axis of the coordinate system is along the axis of the cut continuum manipulator, the z-axis is perpendicular to the plane of symmetry of the flexible beam of segment b, and the y-axis conforms to the direction of the right-hand coordinate system. In the local coordinate system The position vector from the end of the beam of the nth segment a part of the lower cut continuum manipulator to the load application point at the end of the lower cut continuum manipulator; It is the tension on the i-th cable of the n-th segment a part of the cut continuum manipulator; It is the end load of the cut continuum manipulator.

[0079] The cut-and-continue manipulator arm reaches a state of equilibrium under the influence of cable tension and load at its end. In this equilibrium state, the section of the cut-and-continue manipulator arm behind the end of this portion of the beam is considered an isolator. In this equilibrium state, this isolator is subjected to cable tension... End load The beam is in equilibrium under the action of the forces exerted on its ends. Therefore, the forces at the beam ends can be solved from the equilibrium equations involving these three forces.

[0080] Several basic coordinate transformation matrices and translation matrices are predefined as follows: The two rotation transformation matrices are: and ;in, Used for rotation around the Z-axis, Used for rotation around the Y-axis.

[0081] (4)

[0082] (5)

[0083] (6)

[0084] in, It is a 3x1 position vector. The deflection angle of the beam in section a of the manipulator arm of the cut continuum. The deflection angle of the beam in section b of the cut continuum manipulator.

[0085] like Figure 5 As shown, This represents the position vector at the end of the beam; the superscript indicates that the vector is in the local coordinate system. The text indicates that part a can only bend in the xy plane, therefore... It can be written as = .

[0086] With local coordinate system The cable tension is calculated as follows:

[0087] (7)

[0088] in, It is the position vector of the guide hole of part a, represented in the local coordinate system, and it lies in the plane of the guide plate below part a;

[0089] (8)

[0090] This represents the position vector of the guide hole in section a on the guide plate plane at the end of the beam. Parameter This indicates the deflection angle of the beam in section a.

[0091] Similarly, in the local coordinate system In part b, the cable tension can be expressed as follows:

[0092] (9)

[0093] (10)

[0094] Part b can only bend in the xz plane, therefore It can be written as = .

[0095] It is the position vector of the guide hole in part b, represented in the local coordinate system. This represents the position vector of the guide hole in part b on the guide plate plane at the end of the beam.

[0096] To transfer the tension in each cable to the end of the beam, the position vector from the end of the beam to the wire hole needs to be calculated, as shown below:

[0097] (11)

[0098] (12)

[0099] in, In the local coordinate system The position vector from the end of the beam in section a of the nth segment of the lower cut continuum manipulator to the hole of the i-th cable conductor. In the local coordinate system The position vector from the end of the beam of the nth segment b of the lower cut continuum manipulator to the hole of the i-th cable conductor.

[0100] In this implementation, we focus on the force load acting on the end of the manipulator arm of the cut continuum, while neglecting the end moment. End load of the cut continuum manipulator arm. Defined in the global coordinate system. Transforming to a local coordinate system is necessary. To illustrate this, consider part a of the nth segment.

[0101] force In the local coordinate system The expression is as follows:

[0102] (13)

[0103] The deformation units of the slit continuum manipulator are numbered starting from 1, and there are no... and Definition of global framework. Defined as with Consistent, therefore The expression for the end load in the [framework name] is the same as that in the global frame. Therefore, the definition is... and It is an identity matrix.

[0104] Following the same principle, Local coordinate system The expression in the text is as follows:

[0105] (14)

[0106] like Figure 4 As shown, Load from the end of the beam to the end of the cut continuum manipulator The position vector of the applied point is shown below:

[0107] (15)

[0108] in Indicates the number of deformable elements.

[0109] like Figure 6 As shown, The vector representing the thickness direction of the conductor disk can be expressed as: , L is the thickness of the conductor plate, t is the length of the beam, and w is the width of the beam. It is the inner diameter of the incision continuous manipulator arm. It is the outer diameter of the manipulator arm of the cut continuum. (In the local coordinate system) , It is the origin of the coordinate system.

[0110] Similarly, the position vector from the end of beam b to the point where the end load is applied can be represented as:

[0111] (16)

[0112] Therefore, the forces and moments applied at the ends of the beam can be calculated, as shown below:

[0113] (17)

[0114] (18)

[0115] (19)

[0116] (20)

[0117] in, and These are the forces and moments applied to the ends of beam section a. Similarly, and This represents the force and moment applied to the end of the beam at part b. The superscripts on these vectors indicate that the vectors are located in their respective local coordinate systems.

[0118] The following compatibility equations are established based on the elastic deformation of the beam:

[0119] First, force and torque were made dimensionless, such as Figure 7 As shown:

[0120] (twenty one)

[0121] The bending in part a is caused by the components of force in the x and y directions. and and the torque component in the z-direction Caused by. In the above equation, This represents the force vector in the local coordinate system. The x-axis component. Similarly... The force vector in the local coordinate system Lower y direction component, express The moment component in the z-direction. E is the Young's modulus of the material, and I represents the second moment of inertia of the cross section.

[0122] Part B is in It bends around the y-axis. Similarly, the dimensionless forces and moments are as follows:

[0123] (twenty two)

[0124] These are the x and y components of the force and the z-direction torque experienced by part b during bending, respectively.

[0125] Then, the constraint model of the nth compliant mechanism beam can be written as:

[0126] (twenty three)

[0127] (twenty four)

[0128] (25)

[0129] (26)

[0130] in, In the local coordinate system The x-axis component of the dimensionless coordinates of the end of the nth segment (a) of the lower cut continuum manipulator. In the local coordinate system The dimensionless y-axis component of the beam end of the nth segment a of the lower cut continuum manipulator. In the local coordinate system The x-axis component of the dimensionless coordinates of the end of the beam in section b of the nth segment of the lower cut continuum manipulator. In the local coordinate system The z-axis component of the dimensionless coordinate of the end of the beam in the nth segment b of the lower cut continuum manipulator. It is the deflection angle of the beam in section a of segment n of the continuous cutting manipulator. It is the deflection angle of the beam in section b of the nth segment of the cut continuum manipulator. L is the length of the beam.

[0131] The thickness of the beam is represented by t. A, B, C, and D are coefficient matrices, specifically defined as follows:

[0132] (27)

[0133] Expanding the equations for the forces applied to the ends of the beam and combining them with the equations above, we can derive a set of static equilibrium equations.

[0134] S103: The relationship between cable variation and the deformation parameters of the cutting continuum manipulator is introduced into the static model as a constraint equation, and the perception of three-dimensional interactive force is realized through the constraint equation.

[0135] Based on the established static model of the cut-out continuous manipulator, the deformation parameters of the cut-out continuous manipulator can be determined by solving the static model under given cable tension and external end load.

[0136] Cable variation is expressed as The relationship between it and the deformation parameters is shown below:

[0137] (28)

[0138] Consider the interaction force information between the end of the cut continuum manipulator arm and the environment; add the equation for the distribution plane at the end of the cut continuum manipulator arm, as follows:

[0139] (29)

[0140] in It is the direction vector of the load at the end of the manipulator arm of the cut continuum. It refers to the magnitude of the interaction force.

[0141] S104: Obtain the cable variation and cable tension during the movement of the continuous manipulator. Based on the cable tension distribution, static model and constraint equations, calculate the force on the continuous manipulator through iterative calculation.

[0142] Specifically, the cable variation can be obtained by reading the encoder of the motor driving the cable, and the cable tension can be obtained by recursion using equation (3).

[0143] By combining the above 29 equations, the magnitude of the interaction force at the end of the manipulator of the cut continuum can be calculated using a numerical iteration method.

[0144] Example 2

[0145] In one or more embodiments, a sensorless force sensing system for a slit continuum manipulator is disclosed, comprising:

[0146] The cable tension analysis module is used to analyze the cable tension transmission relationship and obtain the cable tension distribution inside each deformation unit;

[0147] The static model building module is used to perform static analysis on the cut continuum manipulator, and to build a static model of the cut continuum manipulator using a beam constraint model.

[0148] The constraint equation construction module is used to introduce the relationship between cable variation and the deformation parameters of the cut continuum manipulator into the static model as constraint equations;

[0149] The end-effector interaction force calculation module is used to obtain the cable variation and cable tension during the movement of the continuous manipulator. Based on the cable tension distribution, static model and constraint equations, the interaction force at the end of the continuous manipulator is obtained through iterative calculation.

[0150] The specific implementation methods of the above modules are the same as those in Example 1, and will not be described in detail again.

[0151] Example 3

[0152] In one or more embodiments, a terminal device is disclosed, including a server. The server includes a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the program, it implements the sensorless force sensing method for the slit continuum manipulator in Embodiment 1. For simplicity, further details are omitted here.

[0153] It should be understood that in this embodiment, the processor can be a central processing unit (CPU), or it can be other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor can be a microprocessor or any conventional processor, etc.

[0154] Memory may include read-only memory and random access memory, and provides instructions and data to the processor. A portion of memory may also include non-volatile random access memory. For example, memory may also store information about the device type.

[0155] In the implementation process, each step of the above method can be completed by the integrated logic circuits in the processor hardware or by software instructions.

[0156] Example 4

[0157] In one or more embodiments, a computer-readable storage medium is disclosed, wherein a plurality of instructions are stored, the instructions being adapted to be loaded by a processor of a terminal device and executed by the sensorless force sensing method of the cut continuum manipulator in Embodiment 1.

[0158] While the specific embodiments of the present invention have been described above in conjunction with the accompanying drawings, this is not intended to limit the scope of protection of the present invention. Those skilled in the art should understand that various modifications or variations that can be made by those skilled in the art without creative effort based on the technical solutions of the present invention are still within the scope of protection of the present invention.

Claims

1. A sensorless force sensing method for a cut continuum manipulator, characterized in that: include: Analyze the cable tension transmission relationship and obtain the cable tension distribution inside each deformation unit; The static analysis of the notch continuum manipulator is carried out, and the static model of the notch continuum manipulator is established using the beam constraint model; The relationship between the cable variation and the deformation parameters of the cut continuum manipulator is introduced into the static model as a constraint equation. The cable variation and cable tension during the movement of the incision continuum manipulator are obtained, and the interaction force at the end of the continuum manipulator is obtained through iterative calculation based on the cable tension distribution, static model and constraint equation. The specific tension transmission relationship of the cables inside each deformation unit is: Among them, T a,i,n+1 represents the tension on the i-th cable in the a-th section of the n+1-th segment of the cut continuum, T b,i,n represents the tension on the i-th cable in the b-th section of the n-th segment of the cut continuum, T a,i,n represents the tension on the i-th cable in the a-th section of the n-th segment of the cut continuum; k(β n ), k(θ n ), k(θ n+1 ) are the tension transfer coefficients, β n is the deflection angle of the beam of the nth section b of the notched continuum manipulator, θ n is the deflection angle of the beam of the nth segment a of the notch continuum manipulator, θ n+1 It is the deflection angle of the beam of section a of the n+1th section of the notched continuum operating arm.

2. A sensorless force sensing method for a continuous incision manipulator according to claim 1, characterized in that: The static analysis of the notch continuum operating arm is carried out, and the force analysis model of the ends of each beam of the notch continuum operating arm is established, specifically: in, and are the force and moment applied to the end of the beam in part a, and represents the forces and moments applied to the ends of the beam in part b; In the local coordinate system R a,n The tension on the cable in section a of the nth segment of the lower cut continuum, In the local coordinate system R b,n The tension on the cable in part b of the nth segment of the lower cut continuum; Indicates the load force at the end of the cut continuum operating arm t F in the local coordinate system R a,n The following expression, Indicates the load force at the end of the cut continuum operating arm t F in the local coordinate system R b,n The following expression; In the local coordinate system R a,n The position vector from the end of the beam of the nth segment a of the lower cut continuum manipulator to the wire hole of the i-th cable, In the local coordinate system R b,n The position vector from the end of the beam of the nth segment b of the lower cut continuum manipulator to the wire hole of the i-th cable; In the local coordinate system R a,n Load from the end of the beam of the nth section a of the lower cut continuum operating arm to the end of the cut continuum operating arm t The position vector of the point where F is applied, In the local coordinate system R b,n Load from the end of the beam of the nth section b of the lower cut continuum operating arm to the end of the cut continuum operating arm t Position vector of the point at which F is applied.

3. A sensorless force sensing method for a continuous incision manipulator according to claim 2, characterized in that: The constraint model of the nth compliant mechanism beam is: in, In the local coordinate system R a,n The x-axis component of the dimensionless coordinate of the end of the beam of the nth segment a of the lower cut continuum manipulator, In the local coordinate system R a,n The y-axis component of the dimensionless coordinate of the end of the beam of the nth segment a of the lower cut continuum manipulator; In the local coordinate system R b,n The x-axis component of the dimensionless coordinate of the end of the beam of the nth section b of the lower cut continuum manipulator, In the local coordinate system R b,n The z-axis component of the dimensionless coordinate of the end of the beam of the nth section b of the lower cut continuum manipulator; β n is the deflection angle of the beam of the nth section b of the notch continuum manipulator, θ n is the deflection angle of the beam of the nth segment a of the incision continuum manipulator; L is the length of the beam, t is the thickness of the beam, A, B, C and D are the coefficient matrices; f a,n,x 、f a,n,y 、m a,n,z are the components of force in the x and y directions and the moment in the z direction for the bending of part a; f b,n,x f b,n,z m b,n,y They are the components of force in the x and y directions and the moment in the z direction acting on the bending of part b.

4. A sensorless force sensing method for a continuous incision manipulator according to claim 3, characterized in that: The static model of the notch continuum manipulator is constructed by combining the tension transmission relationship of the cables inside each deformation unit, the force analysis model at the end of each beam of the notch continuum manipulator, and the constraint model of each compliant mechanism beam.

5. The sensorless force sensing method of the incision continuum manipulator according to claim 1, characterized in that: The relationship between the cable variation and the deformation parameters of the cut continuum manipulator is as follows: Among them, Δl i is the cable variation, In the local coordinate system R a,n The position vector of the guide hole in part a is represented by is the position vector of the guide hole on the plane of the guide plate where the end of the beam is located; In the local coordinate system R b,n The position vector of the guide hole in part b is represented by is the position vector of the guide hole on the guide plate plane where the end of the beam is located, n t Indicates the number of deformation units.

6. The sensorless force sensing method of the incision continuum manipulator according to claim 5, characterized in that: Also includes: Considering the interaction force information between the end of the incision continuum manipulator and the environment, the equation of the distribution plane of the end of the incision continuum manipulator is added, specifically: t F= t Fη; Where η is the direction vector of the load at the end of the notched continuum manipulator, t F is the magnitude of the interaction force, t F is the load at the end of the notched continuum operating arm.

7. A sensorless force sensing system for an incision continuum manipulator, characterized in that: The sensorless force sensing method of the incision continuum manipulator according to any one of claims 1 to 6 comprises: Cable tension analysis module, used to analyze the cable tension transmission relationship and obtain the cable tension distribution inside each deformation unit; Static model building module, used to perform static analysis on the notch continuum manipulator, and to establish a static model of the notch continuum manipulator using a beam constraint model; A constraint equation building module is used to introduce the relationship between the cable variation and the deformation parameters of the cut continuum manipulator into the static model as a constraint equation; The end interaction force calculation module is used to obtain the cable variation and cable tension during the movement of the incision continuum manipulator, and obtain the interaction force at the end of the continuum manipulator through iterative calculation based on the cable tension distribution, static model and constraint equation.

8. A terminal device, comprising a processor and a memory, wherein the processor is used to implement instructions; and the memory is used to store multiple instructions, characterized in that: The instructions are suitable for being loaded by a processor and executing the sensorless force sensing method of the incision continuum manipulator arm as described in any one of claims 1-6.

9. A computer-readable storage medium storing a plurality of instructions, characterized in that: The instructions are suitable for being loaded by a processor of a terminal device and executing the sensorless force sensing method of an incision continuum manipulator arm as described in any one of claims 1-6.

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