Continuum robot detection apparatus and method based on fiber bragg grating sensing

Abstract

A continuum robot (1) detection apparatus based on fiber Bragg grating sensing. The apparatus is characterized by being used for force sensing in a confined space. The apparatus comprises a continuum robot (1), a fiber Bragg grating array and a syringe, wherein the fiber Bragg grating array comprises a plurality of fiber optic sensors (2), and each fiber optic sensor (2) is provided with a plurality of groups of Bragg gratings (FBG-1, FBG-2, FBG-3); the plurality of optical fiber optic sensors (2) are arranged in the circumferential direction of the continuum robot (1) in through holes provided on a tube wall of the continuum robot (1), and are used for measuring an external contact force during traveling of the continuum robot (1), and the plurality of optical fiber optic sensors (2) are all arranged parallel to a longitudinal axis of the continuum robot (1); and the syringe is arranged in an inner hole of the continuum robot (1), and comprises an injection needle (4) and an injection needle catheter (3) coaxially sleeved outside the injection needle (4), the injection needle (4) is used for injecting a drug, and the injection needle (4) and the injection needle catheter (3) are both arranged parallel to the longitudinal axis of the continuum robot (1).

Description

Fiber bragg grating sensing based continuum robot detection device and method TECHNICAL FIELD

[0001] The present application relates to the technical field of medical instrument sensing, in particular to a fiber bragg grating sensing based continuum robot detection device and method, in particular to a fiber bragg grating sensing based narrow space ear canal continuum robot detection method and detection device. BACKGROUND

[0002] The ear canal is a narrow and fragile structure in the human body, and medical diagnosis and treatment in the ear canal has certain risks, while a highly flexible and highly maneuverable continuum robot can provide reliable and safe assistance to medical personnel. The key technology of the ear canal continuum robot is the force sensing method and small size creation design. The fiber bragg grating sensor has the advantages of small size, high sensitivity, no electromagnetic interference, good biocompatibility, etc., and can provide real-time information of the continuum, which has good adaptability with the continuum robot, so as to be applied to minimally invasive surgery.

[0003] The fiber bragg grating array is usually engraved in the fiber core as a sensing unit, and its characteristic is that it has a strong reflection effect only on a certain specific narrow bandwidth of wavelength, and the reflection center wavelength has a good linear mathematical relationship with external strain, temperature and other physical quantities. When the optical fiber is twisted, stretched, bent and temperature changes, the reflection spectrum center wavelength will shift, and the key characteristic parameters are the changes of strain and temperature. Such characteristics enable the fiber bragg grating to measure the deformation and force in a narrow space, which has guiding significance for the operator in ear canal minimally invasive surgery.

[0004] The fiber bragg grating mainly relies on the linear relationship between strain and reflection spectrum center wavelength for force sensing in the interventional continuum robot. The fiber bragg grating sensing is suitable for small size real-time medical diagnosis and treatment, and has good biocompatibility, but the force sensing of the continuum with complex and variable shape is still a problem, especially when the continuum robot realizes multi-functional operation while maintaining the overall small size.

[0005] The patent document with publication number CN114667104A discloses an optical force sensor with a catheter / sheath, which combines fiber bragg grating with a medical device for intracardiac surgery and proposes a scheme to quantify the contact force of the medical device pressed against the tissue. Although the fiber bragg grating sensing is combined with a medical flexible instrument, it only detects the axial force information applied to the tip of the instrument, and the size of the instrument is not suitable for the narrow space in the ear canal.

[0006] SUMMARY

[0007] In view of the defects in the prior art, the present application aims to provide a continuum robot detection device and method based on fiber Bragg grating sensing.

[0008] The continuum robot detection device based on fiber Bragg grating sensing provided by the present application is used for force sensing in a narrow space and comprises a continuum robot, a fiber Bragg grating array and a syringe.

[0009] The plurality of fiber sensors are arranged in the through holes of the tube wall of the continuum robot along the circumference of the continuum robot and are used for detecting external contact force during the travel of the continuum robot, and the plurality of fiber sensors are arranged in parallel to the longitudinal axis of the continuum robot.

[0010] The syringe is arranged in the inner hole of the continuum robot and comprises a syringe needle and a syringe needle guide tube coaxially sleeved outside the syringe needle, the syringe needle is used for injecting medicine, and the syringe needle and the syringe needle guide tube are arranged in parallel to the longitudinal axis of the continuum robot.

[0011] Preferably, among the plurality of Bragg gratings on each fiber sensor, a spacing area is arranged between adjacent Bragg gratings.

[0012] Preferably, the fiber Bragg grating array comprises three fiber sensors, the three fiber sensors are equidistantly arranged along the radial direction of the longitudinal axis of the continuum robot and are spaced apart by 120° from each other, and three groups of Bragg gratings are arranged in sequence and equidistantly along the longitudinal direction on each fiber sensor, which are FBG-1, FBG-2 and FBG-3 respectively.

[0013] Preferably, the camera and the light source are arranged in the inner hole of the continuum robot (1) and are used for shooting images and providing visual image information in front of the travel path during the travel of the continuum robot.

[0014] The camera and the light source are arranged in parallel to the longitudinal axis of the continuum robot.

[0015] Preferably, the light source is two, and the two light sources are arranged on the two sides of the camera respectively.

[0016] Preferably, assembly gaps exist between the syringe, the camera, the light source and the tube wall of the continuum robot.

[0017] The continuum robot detection method based on fiber Bragg grating sensing provided by the present application adopts the continuum robot detection device based on fiber Bragg grating sensing and comprises the following steps.

[0018] Step 1: Real-time calculation of the curvature and torsion angle of each fiber sensor based on the data of multiple fiber sensors in the fiber Bragg grating array during the movement of the continuum robot detection device in a narrow space;

[0019] Step 2: Real-time determination of the Bragg center wavelength change by the fiber Bragg grating array, and calculation of the strain information of each Bragg grating according to the curvature and torsion angle information of each fiber sensor;

[0020] Step 3: Based on the equilibrium equation and constitutive equation of the Cosserat rod model, the size, direction and position information of the contact force on the continuum robot are perceived according to the strain information, curvature and torsion angle information of each Bragg grating.

[0021] Preferably, the fiber Bragg grating array includes three fiber sensors arranged at 120° to each other, and FBG-1, FBG-2 and FBG-3 are arranged longitudinally on each fiber sensor;

[0022] In step 2, the strain information ε of each Bragg grating is calculated according to the curvature and torsion angle information of each fiber sensor. ij (i,j = 1,2,3), wherein j represents the fiber sensor at different positions, and i represents different Bragg gratings on each fiber sensor;

[0023] The strain on each Bragg grating of each fiber sensor is expressed as curvature and torsion angle:

[0024] In the formula, r is the distance between the center of the Bragg grating and the center of the continuum robot, κ j is the curvature at the jth fiber sensor, θ bj is the torsion angle at the jth fiber sensor, θ 1j is the angle between the line connecting the center of the top fiber sensor and the center of the continuum robot and the bending direction of the continuum robot, ε tj is the influence of the ambient temperature on the strain measurement;

[0025] The curvature and torsion angle at each Bragg grating of each fiber sensor are calculated by Formula One, and the curvature vector is defined as follows:

[0026] At the jth fiber sensor, the following geometric parameters are obtained: curvature Torsion angle θ bj = ∠κ appj , and the shear rate

[0027] Preferably, in step 3, the angular strain vector of each fiber sensor is defined according to the curvature and twist angle information of each Bragg grating:

[0028] The internal force moment vector m is calculated by the constitutive equation of the Cosserat rod model: j = K u (u j -u0) Equation Four

[0029] In Equation Three and Equation Four, u j and m j are the [3x1] internal force and internal force moment vectors at each fiber sensor, K u is the [3x3] bending and torsion stiffness matrix, and u0 is the [3x1] reference angular strain vector, which is defined as u0 = [0] 3×1 .

[0030] The contact force vector at each fiber sensor is calculated by the equilibrium equation of the Cosserat rod model using the internal force vector u j and the internal force moment vector m j obtained from Equation Three and Equation Four:

[0031] In Equation Five, Equation Six, and Equation Seven, f j is the contact force vector at each fiber sensor, is the anti-symmetric form of the angular strain matrix, is the anti-symmetric form of the linear strain matrix, l j is the contact force moment vector at each fiber sensor, and l j is defined as [0] 3×1 .

[0032] Compared with the prior art, the present application has the following beneficial effects:

[0033] 1、The present application has a simple structure and is easy to operate, and by adopting a small-scale fiber Bragg grating and continuum robot generative design, including a syringe for completing ear canal injection of drugs and the like, a camera for providing real-time continuum end visual information, and a fiber Bragg grating (FBG) for providing real-time continuum contact force information, the problem of multifunctional integration of a continuum robot for diagnosis and treatment in a narrow ear canal space is solved, and the overall size of the continuum robot is greatly reduced.

[0034] 2、The application solves the force sensing problem of small-scale continuum robots in the narrow space of the ear canal by combining the fiber Bragg grating sensor with the Cosserat rod model, and provides real-time contact force information, including the size and direction of the contact force and the position of the contact. BRIEF DESCRIPTION OF DRAWINGS

[0035] Other features, objects, and advantages of the application will become more apparent from the following detailed description of non-limiting embodiments, when read in conjunction with the accompanying drawings:

[0036] Fig. 1 is a structural schematic diagram of a continuum robot detection device in the application;

[0037] Fig. 2 is a cross-sectional schematic diagram of the continuum robot detection device in the application;

[0038] Fig. 3 is a distribution schematic diagram of a fiber Bragg grating array of the continuum robot detection device in the application;

[0039] Fig. 4 is a longitudinal distribution schematic diagram of a Bragg grating on an optical fiber of the continuum robot detection device in the application;

[0040] Fig. 5 is a flow chart of a continuum robot detection method in the application.

[0041] The figures show:

[0042] Continuum robot 1 Injection needle 4

[0043] Optical fiber sensor 2 Camera 5

[0044] Injection needle catheter 3 Light source 6 DETAILED DESCRIPTION

[0045] The application will be described in detail below in conjunction with specific embodiments. The following embodiments will help those skilled in the art to further understand the application, but do not limit the application in any form. It should be noted that those skilled in the art can make several changes and improvements without departing from the concept of the application. These are within the scope of protection of the application.

[0046] The application discloses a continuum robot detection device and method based on fiber Bragg grating sensing suitable for narrow spaces, which is aimed at the operation of injecting drugs in the narrow space of the ear canal. The continuum robot can realize force sensing while maintaining the small size of the continuum robot, ensuring accurate and safe operation of the ear canal injection process.

[0047] The application provides a continuum robot detection device based on fiber Bragg grating sensing, which is used for force sensing in a narrow space and comprises a continuum robot 1, a fiber Bragg grating array and a syringe. The fiber Bragg grating array comprises a plurality of fiber sensors 2, each of which is provided with a plurality of groups of Bragg gratings. The plurality of fiber sensors 2 are arranged in the through holes of the tube wall of the continuum robot 1 along the circumference of the continuum robot 1, and are used for detecting the contact external force during the movement of the continuum robot 1. The plurality of fiber sensors 2 are arranged in parallel to the longitudinal axis of the continuum robot 1. The syringe is arranged in the inner hole of the continuum robot 1 and comprises a syringe needle 4 and a syringe needle guide pipe 3 coaxially arranged outside the syringe needle 4. The syringe needle 4 is used for injecting medicine, and the syringe needle 4 and the syringe needle guide pipe 3 are arranged in parallel to the longitudinal axis of the continuum robot 1. In each group of Bragg gratings on each fiber sensor 2, a spacing area is arranged between adjacent Bragg gratings. The application further comprises a camera 5 and a light source 6, which are arranged in the inner hole of the continuum robot 1 and move with the continuum robot 1, and are used for shooting images and providing visual image information in front of the movement path. The camera 5 and the light source 6 are arranged in parallel to the longitudinal axis of the continuum robot 1. Preferably, the light source 6 is two, and the two light sources 6 are arranged on the two sides of the camera 5.

[0048] The application further provides a continuum robot detection method based on fiber Bragg grating sensing, which adopts the continuum robot detection device based on fiber Bragg grating sensing and comprises the following steps.

[0049] Step 1: during the movement of the continuum robot detection device in the narrow space, the curvature and the torsion angle of each fiber sensor 2 are calculated in real time based on the data of the plurality of fiber sensors 2 in the fiber Bragg grating array.

[0050] Step 2: the fiber Bragg grating array determines the Bragg center wavelength change in real time, and the strain information of each Bragg grating is calculated according to the curvature and the torsion angle information of each fiber sensor 2.

[0051] Step 3: the size, direction and position information of the contact force on the continuum robot 1 are perceived based on the equilibrium equation and the constitutive equation of the Cosserat rod model according to the strain information, the curvature and the torsion angle information of each Bragg grating.

[0052] The above is the basic embodiment of the application, and the scheme of the application will be further described through the following preferred embodiments.

[0053] Embodiment 1

[0054] The embodiment provides a kind of based on fiber bragg grating sensing in narrow space inside continuum robot detection device, including: continuum robot 1, fiber bragg grating array, injector, camera 5 and light source 6.The fiber bragg grating (FGB) array includes three optical fiber sensors 2, and three groups of bragg grating FBG-1, FBG-2, FBG-3 are contained on the optical fiber sensor 2, the optical fiber sensor 2 is arranged in the through hole of the wall of the continuum robot 1, detects the contact external force in the travel process of continuum robot 1.

[0055] The injector includes injection needle catheter 3 and injection needle 4, and is arranged in parallel in the hole of continuum robot 1, and after continuum robot 1 passes through middle ear path and enters inner ear to reach target injection round window, injection medicine is injected into target injection round window.The camera 5 and light source 6 are arranged in the hole of continuum robot 1, and travel along with continuum robot 1 and take image, provide visual image information in front of travel path.

[0056] The fiber bragg grating (FBG) sensing array 2 follows continuum robot 1 along ear canal and enters inner ear from middle ear through tympanic membrane hole, and injection needle 4 is aligned with target round window of inner ear to complete the injection of medicine.During this process, optical fiber sensor 2 is combined with camera 5 to provide travel path information, to assist operator to avoid important structure, such as tympanic membrane membrane hole, auditory ossicles, to avoid causing irreversible damage to patient hearing.

[0057] Further, three optical fiber sensors 2 (FBG) are evenly distributed in the through hole of the continuum robot 1 pipe wall, and are coaxially embedded with a 120° angle between each other and the continuum longitudinal axis to sense the contact force of the continuum. The cross section is shown in FIG. 3, and the grating regions are longitudinally distributed, and each grating region is engraved with three fiber Bragg gratings: FBG-1, FBG-2, and FBG-3. The grating region length is 1 mm, the grating region interval is 1 mm, and the effective grating region sensing total length is 5 mm, which is used to cover the path of about 5 mm from the middle ear to the inner ear target round window, and is arranged within the 6.45 mm length of the continuum flexible deformable body to ensure that the effective sensing length can deform with the continuum. The Bragg grating on the optical fiber sensor 2 is engraved by ultraviolet laser mask, and the diameter of the single optical fiber sensor 2 is controlled to be Φ0.195 mm after the coating layer, as shown in FIG. 4. The fiber Bragg grating 2, the continuum robot 1, the camera 5, and the syringe are integrated as shown in FIGS. 4-5. The movable continuum has an outer diameter of Φ2 mm and an inner diameter of Φ1.3 mm. The three optical fiber sensors 2, the camera 5, the light source 6, and the injection needle catheter 3 are arranged in parallel, wherein the camera 5, the light source 6, and the injection needle catheter 3 are built into the inner hole of the continuum, and the three optical fiber sensors 2 are arranged in the through hole on the pipe wall of the continuum robot 1, and are integrated into a detection instrument. The detection instrument can not only obtain visual information of the current environment image during the movement of the continuum, but also can simultaneously obtain the contact force information of the continuum. The gap between the internal components of the continuum robot 1 and the continuum is kept, and the components can be inserted through the gap. The syringe catheter 3 has an outer diameter of Φ0.25 mm and an inner diameter of Φ0.15 mm, and the end effector injection needle 4 coaxial with the syringe catheter 3 has a diameter of Φ0.10 mm, which can pass through the syringe catheter 3 to perform injection operation. The fiber Bragg grating detection instrument enters the detected ear canal with the control of the continuum robot 1, and during the process of the continuum robot 1 entering the inner ear from the middle ear, the optical fiber sensor 2 will generate strain, and through the force sensing model, the contact force information of the current continuum is output.

[0058] Embodiment 2

[0059] The embodiment provides a force sensing method based on the above-mentioned continuum robot detection device. The optical fiber sensor 2 determines the Bragg center wavelength change and strain calculation in real time, and obtains the strain information ε of each Bragg grating point ij (i,j = 1,2,3), wherein j represents the optical fiber sensor 2 at different positions, and i represents different fiber Bragg gratings on each optical fiber sensor 2.

[0060] Further, the curvature and torsion angle based on the data of the three optical fiber sensors 2 with an interval of 120° are calculated. The strain of each optical fiber grating can be expressed as the curvature and torsion angle:

[0061] where r is the distance between the center of the fiber sensor 2 and the center of the continuum, κ j is the curvature of the multi-core fiber sensor 2 at the jth fiber sensor 2, θ bj is the twist angle of the multi-core fiber sensor 2 at the jth fiber sensor 2, θ 1j is the angle between the line connecting the center of the tip fiber sensor 2 and the center of the continuum robot 1 and the bending direction of the continuum, ε tj is the influence of the ambient temperature on the strain measurement. Then the curvature and twist angle at each fiber sensor 2 can be calculated by equation (1), and the curvature vector is defined as follows:

[0062] Then, at the jth fiber sensor 2, the following geometric parameters can be obtained: curvature κ twist angle θ bj = ∠κ appj , and the shear strain ε

[0063] Further, based on the geometric parameters obtained by the fiber sensor 2, the equilibrium equation and the constitutive equation of the Cosserat rod model are used to complete the perception of the size, direction and position information of the contact force on the continuum robot 1. The curvature and twist angle at each fiber sensor 2 obtained from the above can define the angular strain vector at each fiber sensor 2:

[0064] The internal force moment vector m j can be calculated from the constitutive equation of the Cosserat rod model: u (u j -u0) (4)

[0065] In equations (3) and (4), u j and m j are the [3x1] internal force and internal force moment vectors at each fiber sensor 2, K u is the [3x3] bending and torsional stiffness matrix, and u0 is the [3x1] reference angular strain vector, which is defined as u0 = [0] 3×1 .

[0066] The contact force vector at each fiber sensor 2 can be further calculated from the internal force vector u j and the internal force moment vector m j obtained by the equilibrium equation of the Cosserat rod model:

[0067] In equations (5), (6) and (7), fj is the contact force vector at each fiber sensor 2, is the anti-symmetric form of the angular strain matrix, is the anti-symmetric form of the linear strain matrix, l j is the contact moment vector at each fiber grating, since the continuum is not subjected to contact moments, thus l j is defined as [0] 3×1 .

[0068] The three sets of curvature and torsion angle values are obtained by Cosserat modeling to get the continuum force perception results. Since the fiber sensor 2 is a short length distributed sensor, the curvature and torsion information needs to be interpolated to obtain more complete information on the length of the continuum robot 1. The present application solves the problem of force perception of small-scale continuum robots in the narrow space of the ear canal by combining fiber Bragg grating sensors with the Cosserat rod model, and provides real-time contact force information, including the size and direction of the contact force and the position of the contact.

[0069] Those skilled in the art know that, in addition to implementing the system provided by the present application and each device, module and unit thereof in the form of pure computer readable program code, the same functions can also be achieved by logically programming the method steps to make the system provided by the present application and each device, module and unit thereof in the form of logic gates, switches, application specific integrated circuits, programmable logic controllers and embedded microcontrollers. Therefore, the system provided by the present application and each device, module and unit thereof can be considered as a hardware component, and the devices, modules and units included therein for achieving various functions can also be considered as structures within the hardware component; the devices, modules and units for achieving various functions can also be considered as both software modules for implementing methods and structures within hardware components.

[0070] In the description of the present application, it should be understood that the terms "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application.

[0071] The specific embodiments of the present application are described above. It should be understood that the present application is not limited to the above specific embodiments, and those skilled in the art can make various changes or modifications within the scope of the claims, which does not affect the essential content of the present application. The embodiments of the present application and the features in the embodiments can be arbitrarily combined with each other without conflict.

Claims

1. A continuum robot sensing device based on fiber Bragg grating sensing, characterized by, The application relates to force sensing in a narrow space, comprising a continuum robot (1), a fiber Bragg grating array and a syringe, the fiber Bragg grating array comprising a plurality of fiber sensors (2), each of which is provided with a plurality of Bragg gratings; The plurality of fiber sensors (2) are arranged in the through holes of the tube wall of the continuum robot (1) along the circumference of the continuum robot (1) and are used for detecting external contact force during the movement of the continuum robot (1), and the plurality of fiber sensors (2) are arranged in parallel to the longitudinal axis of the continuum robot (1). The syringe is arranged in the inner hole of the continuum robot (1) and comprises a syringe needle (4) and a syringe needle guide tube (3) coaxially sleeved outside the syringe needle (4), the syringe needle (4) is used for injecting medicine, and the syringe needle (4) and the syringe needle guide tube (3) are arranged in parallel to the longitudinal axis of the continuum robot (1).

2. The fiber Bragg grating sensor based continuum robot detection apparatus of claim 1, wherein, The plurality of Bragg gratings on each fiber sensor (2) are provided with interval regions between adjacent Bragg gratings.

3. A continuum robot sensing device based on Fiber Bragg Grating sensing according to claim 2, characterized in that, The fiber Bragg grating array comprises three fiber sensors (2), the three fiber sensors (2) are equidistantly arranged along the radial direction of the longitudinal axis of the continuum robot (1) and are spaced apart by 120 degrees, and each fiber sensor (2) is provided with three groups of Bragg gratings which are equidistantly arranged in sequence along the longitudinal direction, namely FBG-1, FBG-2 and FBG-3.

4. The fiber Bragg grating sensor based continuum robot detection apparatus of claim 1, wherein, The camera (5) and the light source (6) are arranged in the inner hole of the continuum robot (1) and move with the continuum robot (1) and are used for shooting images and providing visual image information in front of the moving path. The camera (5) and the light source (6) are arranged in parallel to the longitudinal axis of the continuum robot (1).

5. A continuum robot sensing device based on Fiber Bragg Grating sensing according to claim 4, characterized in that, The light source (6) is two, and the two light sources (6) are arranged on the two sides of the camera (5).

6. The fiber Bragg grating sensor based continuum robot detection apparatus of claim 4, wherein, There are assembly gaps between the syringe, the camera (5), the light source (6) and the tube wall of the continuum robot (1).

7. A continuum robot sensing method based on fiber Bragg grating sensing, characterized by, The continuum robot detection device based on the fiber Bragg grating sensing in any one of claims 1-6 comprises the following steps: Step 1: during the movement of the continuum robot detection device in a narrow space, the curvature and the torsion angle of each fiber sensor (2) are calculated in real time based on the data of the plurality of fiber sensors (2) in the fiber Bragg grating array; Step 2: the fiber Bragg grating array determines the Bragg center wavelength change in real time, and the strain information of each Bragg grating is calculated according to the curvature and the torsion angle information of each fiber sensor (2); Step 3: according to the strain information, the curvature and the torsion angle information of each Bragg grating, the size, the direction and the position information of the contact force on the continuum robot (1) are sensed based on the equilibrium equation and the constitutive equation of the Cosserat rod model.

8. The fiber Bragg grating sensor based continuum robot detection method of claim 7, wherein, The fiber Bragg grating array comprises three fiber sensors (2) arranged at 120° to each other, and FBG-1, FBG-2 and FBG-3 are longitudinally arranged on each fiber sensor (2); In step 2, the strain information ε of each Bragg grating is calculated according to the curvature and torsion angle information of each optical fiber sensor (2) ij (i,j = 1,2,3), where j represents the optical fiber sensor (2) at different positions, and i represents different Bragg gratings on each optical fiber sensor (2); The strain on each Bragg grating of each fiber optic sensor (2) is expressed in terms of curvature and twist angle as: where r is the distance between the center of the Bragg grating and the center of the continuum robot (1), κ j is the curvature at the jth fiber optic sensor (2), θ bj is the twist angle at the jth fiber optic sensor (2), θ 1j is the angle between the line connecting the center of the tip fiber optic sensor (2) and the center of the continuum robot (1) and the bending direction of the continuum robot (1), ε tj is the influence of the ambient temperature on the strain measurement; The curvature and torsion angle at each Bragg grating of each fiber sensor (2) is calculated by Equation One, and the curvature vector is defined as follows: At the jth optical fiber sensor (2), the following geometrical parameters are obtained: curvature twist angle θ bj = ∠κ appj , torsion 9. The fiber Bragg grating sensor based continuum robot detection method of claim 8, wherein, In step 3, the angular strain vector of each fiber sensor (2) is defined from the curvature and twist angle information of each Bragg grating: The internal force moment vector is calculated through the constitutive equation of the Cosserat rod model: m j = K u (u j - u0) Equation Four In equation three and equation four, u j and m j are the [3x1] internal force and internal moment vectors at each fiber optic sensor (2), K u is the [3x3] bending and torsional stiffness matrix, u0 is the [3x1] reference angular strain vector, which is defined as u0 = [0] 3×1 ; By the equilibrium equations of the Cosserat rod model, the internal force vector u j and the internal moment vector m j are calculated at each fiber-optic sensor (2) using the formulas three and four: In formulas five, six, and seven, f j for each fiber optic sensor (2) at the contact force vector, is the anti-symmetric form of the angular strain matrix, is the linear strain matrix in anti-symmetric form, l j is the contact moment vector at each fiber sensor (2), l j is defined as [0] 3×1 .

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