Tendon-like and driving-sensing integrated rope driving device based on composite woven structure

Abstract

The invention discloses a tendon-like and driving sensing integrated rope driving device based on a composite woven structure, and belongs to the technical field of high and new technology drivers. The tendon-like sensor takes a fiber bragg grating as a sensing layer and comprises an optical fiber and an external braided layer, a grating section with a set period is engraved on a fiber core of the optical fiber, the surface of the optical fiber is coated with a polymer coating layer, the braided layer and the optical fiber are subjected to multi-strand cross braiding according to a preset braiding angle, and by controlling the braiding angle, the fiber bragg grating can be sensed. And the axial tension can be linearly transmitted to the fiber bragg grating in proportion. The tendon-like assembly which is simple in structure and can stably work for a long time is designed, then the driving and sensing integrated rope driving device is achieved, and the control performance of a rope driving exoskeleton or a flexible driving system is improved.

Description

Technical Field

[0001] This invention relates to the field of high-tech actuator technology, and more specifically, to a tendon-like device based on a composite braided structure and an integrated drive and sensing rope drive device. Background Technology

[0002] In rope-driven systems, flexible ropes typically use high-strength fibers (such as aramid fibers and ultra-high molecular weight polyethylene fibers) or metals (such as carbon steel wire, stainless steel wire, and galvanized steel wire) as the tension transmission medium, and are dragged by a drive mechanism. To achieve force control and safe human-machine interaction in rope-driven systems, such as exoskeletons or bionic drive systems, the control system needs to acquire tension information in real time.

[0003] See Figure 1 As shown, the existing mainstream solutions include Figure 1 (a) Measurement of driving force Figure 1 (b) Indirect measurement of tension and Figure 1 (c) Three methods for measuring end contact force. In the driving force measurement method, the drag force measurement of the driving mechanism relies on estimating the output torque using the motor drive current. However, this method only calculates the equivalent force on the driving side and cannot reflect the true tension on the load side, meaning there is a calculation error. Indirect tension measurement generally uses an idler mechanism to convert the tension change of the ropes on both sides into force or displacement of the idler shaft. However, this method inevitably increases the complexity of the structure, which is extremely challenging for rope-driven dexterity systems with limited internal controls. End contact force measurement relies on force / tactile sensors on the contact surface. However, this method only measures the result of the final operation and cannot obtain the true tension of a single segment of the driving rope, which is crucial for multi-rope drive systems.

[0004] Existing direct tension measurement is based on rigid body deformation measurement using a resistance strain gauge. The principle involves attaching resistance strain gauges to the surface of a stressed structural component (such as aluminum alloy or steel). When the structure is subjected to stress, the component experiences minute strain, causing the strain gauges to deform due to the bonded connection. This deformation results in a change in resistance, which is then converted into a voltage signal by an external Wheatstone bridge circuit (full bridge, half bridge, or quarter bridge). The limitations of this resistance strain gauge approach are that strain gauges are generally unsuitable for flexible objects like tendon ropes (where bonding is impossible). Even when made to a small size, the adhesive layer between the strain gauge and the substrate is prone to detachment and creep under long-term cyclic loading, affecting measurement accuracy. Furthermore, strain gauges typically only measure single-point stress, and the signal transmission lines are complex, making them unsuitable for long-distance, multi-node flexible rope drive systems.

[0005] Analysis reveals that existing methods typically rely on driving current estimation or external force / tactile sensors, which suffer from the following problems: inability to acquire the true internal force transmitted along the rope path; susceptibility to contact effects caused by friction, guide wheels, and coverings; and separation of driving and sensing, resulting in large size and low integration. In existing rope-driven exoskeletons or flexible driving devices / systems, the true tension inside the tendons (ropes) is difficult to acquire directly, stably, and accurately, hindering efficient force control and safe human-machine interaction applications.

[0006] In summary, the prominent drawbacks of existing technologies lie in the separation of tension measurement from the actual force-bearing path and the low degree of integration between the sensing structure and the tendon. Therefore, there is an urgent need for a body-based actuated sensing tendon material / component that can bear force (achieving actuation), is sensitive to axial force (achieving sensing), and is suitable for closed-loop tension control. Summary of the Invention

[0007] The purpose of this invention is to overcome the shortcomings of the prior art and provide a tendon-like device and a drive sensing integrated rope drive device based on a composite braided structure.

[0008] According to a first aspect of the present invention, a tendon-like structure based on a composite braided structure is provided. The tendon-like structure uses a fiber Bragg grating as a sensing layer and includes an optical fiber and an outer braided layer. The fiber core is engraved with grating segments of a set period, and the surface of the optical fiber is coated with a polymer coating layer. The braided layer and the optical fiber are cross-braided in multiple strands according to a preset braiding angle. By controlling the braiding angle, the axial tension can be linearly transmitted to the fiber Bragg grating in a proportional manner.

[0009] According to a second aspect of the present invention, a drive-sensing integrated rope-driven device is provided. The device includes: the aforementioned tendon-like structure based on a composite braiding structure, an optical demodulation unit, a drive execution unit, and a controller, wherein: One end of the tendon-like structure is connected to the drive source, and the other end is connected to the load side. The optical demodulation unit is used to emit a light beam toward the tendon-like structure and detect the wavelength offset reflected back by the fiber Bragg grating. The drive execution unit serves as the drive source, including a servo motor and a rope winding wheel; The controller calculates the actual tension inside the tendon-like structure based on the wavelength offset using a preset wavelength-tension mapping model, and uses this actual tension as a feedback signal to determine and adjust the output of the servo motor to drive the rope wheel to rotate in order to compensate for the tension deviation.

[0010] In one embodiment, the tension deviation is obtained according to the following steps: The controller receives instructions from the host computer and sets the target tension value. ; The optical demodulation unit acquires the wavelength signal of the fiber Bragg grating inside the tendon-like structure in real time, and converts it into the current real tension according to the preset wavelength-tension mapping model. and real-time deviation value ; Calculate the PID control parameters, including the proportional parameter P, integral parameter I, and derivative parameter D; Based on the calculated PID control parameters, the control quantity is output to the servo motor to drive the rope wheel to rotate and compensate for tension deviation.

[0011] In one embodiment, the wavelength-tension mapping model is calibrated according to the following steps: Establish the mapping relationship between optical signals and physical quantities:

[0012]

[0013] in, It is axial tension. It is the wavelength offset. It is the center wavelength of the fiber Bragg grating. For the strain of tendon-like materials, For the effective photosensitivity coefficient, B is the linear proportionality coefficient, and B is the intercept. Experiments were conducted to determine the tendon-like structure under different tensions. Center wavelength offset The linear proportionality coefficient was obtained by fitting. .

[0014] In one embodiment, the optical demodulation unit is an optical demodulator, which connects multiple tendon-like fiber optic lines to different channels of the same optical demodulator. By etching gratings with different center wavelengths on a single fiber, it is applied to the synchronous monitoring of tension in multiple finger joints of a dexterous hand or multiple degrees of freedom of an exoskeleton.

[0015] In one embodiment, in a dexterous hand application, each finger uses an independent tendon-like structure to drive the distal, mid, and proximal phalanges, enabling real-time acquisition of the actual internal forces of the distal, mid, and proximal phalangeal tendons to sense cross-joint tension.

[0016] In one embodiment, after obtaining the tension information of a single tendon-like muscle, the controller calculates and allocates the target torque of each servo motor based on the feedback of each degree of freedom and in combination with the kinematic model, thereby realizing multi-axis torque distribution, impedance control or admittance control.

[0017] Compared with existing technologies, the advantages of this invention are that it provides a tendon-like material / component that is sensitive to axial tension, integrated with load-bearing components, has a simple structure, and can operate stably for a long time. Furthermore, based on this tendon-like material / component, a rope-driven method and device integrating actuation and sensing are realized. Using this invention, the control performance of rope-driven exoskeletons or flexible drive systems can be directly improved.

[0018] Other features and advantages of the invention will become clear from the following detailed description of exemplary embodiments of the invention with reference to the accompanying drawings. Attached Figure Description

[0019] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments of the invention and, together with their description, serve to explain the principles of the invention.

[0020] Figure 1 This is a schematic diagram of the mainstream rope tension measurement scheme in the existing technology; Figure 2 This is a schematic diagram of the structure of a composite braided tendon material according to an embodiment of the present invention; Figure 3 This is a schematic diagram of the operation of a drive-sensing integrated tendon-like component according to an embodiment of the present invention; Figure 4 This is a schematic diagram of multi-component distributed multi-dimensional sensing operation according to an embodiment of the present invention. Detailed Implementation

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

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

[0023] Techniques, methods, and equipment known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and equipment should be considered part of the specification.

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

[0025] It should be noted that similar labels and letters in the following figures indicate similar items; therefore, once an item is defined in one figure, it does not need to be discussed further in subsequent figures.

[0026] This invention discloses a tendon-like material based on a composite braided structure using a fiber Bragg grating (FBG). The core of its structure is a fiber Bragg grating used as the sensing layer, woven together with high-strength load-bearing fibers. Utilizing the center wavelength of the FBG (… With axial tension The linear offset characteristic enables sensing. When the tendon-like structure is stretched, the embedded FBG generates strain, and the center wavelength of its reflection spectrum shifts, as shown below: (1) in, It is the shift in the center wavelength of the reflection spectrum. For the strain of tendon-like materials, The effective photosensitivity coefficient.

[0027] In summary, this invention designs a composite braided tendon-like material structure, using a fiber Bragg grating (FBG) as the sensing layer. This sensing layer enables a wavelength modulation-based sensing mechanism. Furthermore, the designed composite braided tendon-like material structure can be used to construct an integrated drive and sensing component or device, and the wavelength multiplexing technology of FBG can be utilized to achieve distributed composite sensing capabilities.

[0028] (1) Composite braided tendon material structure.

[0029] The fiber is centered on a single-mode optical fiber containing at least one fiber Bragg grating (FBG). The fiber surface is coated with a sensitizing and protective layer to ensure its mechanical strength during the braiding process. Multiple high-strength fibers are symmetrically cross-braided around the fiber core. By controlling the braiding angle, the axial tension on the rope is proportionally and linearly transmitted to the internal fiber Bragg grating. While maintaining high load transmission capacity, the material possesses an extremely small bending radius and excellent flexibility, appearing identical to a conventional power rope, but exhibiting full-line strain sensing capability.

[0030] (2) Sensing mechanism based on wavelength modulation.

[0031] Shifting the center wavelength of reflected light generated by FBG To sense tension, the wavelength signal is unaffected by transmission distance, changes in cable resistance, or strong electromagnetic interference from surrounding motors. Because the FBG is etched inside the optical fiber, it does not alter the continuity of the rope.

[0032] (3) Drive sensing integrated components and devices.

[0033] The optical demodulation unit includes a broadband light source, a coupler, and a demodulation module, responsible for emitting a light beam to the composite tendon and detecting the wavelength shift of the reflected light in real time; the drive execution unit consists of a servo motor and a rope wheel, with the composite tendon serving as the power transmission medium; the controller calculates the actual tension inside the tendon based on the demodulated wavelength shift using a preset "wavelength-tension" mapping model. This serves as a feedback signal, allowing for real-time adjustment of the motor's output based on control requirements.

[0034] (4) Distributed composite sensing capability.

[0035] By utilizing the wavelength multiplexing technology of FBG, multiple grating points with different center wavelengths can be engraved in a single compound tendon, enabling simultaneous acquisition of the stress state of the rope at different locations (such as at the joint, drive end, and end), thus achieving quasi-distributed tension monitoring.

[0036] This invention constructs a tendon-like component with proprioceptive sensing capabilities by deeply integrating a fiber Bragg grating (FBG) sensor into a high-strength braided rope. The following sections will sequentially describe the construction process of the composite braided tendon-like material, the integrated drive and sensing tendon-like component, the rope-driven closed-loop tension control method, and the integrated drive and sensing rope-driven device.

[0037] 1. Construction process of composite braided tendon materials The core of this invention lies in achieving coaxial or parallel composite bonding of optical fiber and load-bearing fiber. For the grating core material, a single-mode optical fiber can be selected, and grating segments with a specific period can be etched on its core. The surface of the optical fiber is coated with a high-modulus polymer coating layer (such as polyimide) to enhance the interfacial shear force transmission with the external braided layer. Depending on the tension requirements, the load-bearing fiber can also be arranged coaxially with the optical fiber. Subsequently, with the axis of the grating core material as the center, aramid or ultra-high molecular weight polyethylene fibers are braided at a preset angle (e.g., ...). The fibers are cross-woven in multiple strands. By optimizing the angles, it is ensured that stable radial compressive force and axial strain can be generated under axial tension and linearly transmitted to the internal FBG. Figure 2 This is a schematic diagram of a novel tendon-like structure with a multi-layer braided structure, including FBG optical fiber 1, polymer coating layer 2 and protective layer 3, and optionally, load-bearing fiber 4.

[0038] 2. Integrated Drive and Sensing Tendon-like Component Based on the aforementioned composite braided tendon material, this invention constructs a compact and highly interference-resistant integrated drive and sensing component by introducing an optical modulation and demodulation circuit and a traction drive module. This component breaks through the limitation of separation between drive and sensing in traditional rope-driven systems, achieving deep integration of "rope as sensor." The integrated component mainly includes core units such as the composite tendon, the optical modulation and demodulation module, and the traction drive module, as follows: Figure 3 As shown. The composite tendon uses a composite braided rope containing an FBG core as the power transmission medium. One end is connected to the drive source, and the other end is connected to the load side (such as an exoskeleton joint or dexterous hand end). The optical modulation and demodulation module includes a broadband light source and a fiber optic demodulator. The light source injects a continuous spectrum into the fiber optic cable inside the tendon, and the fiber optic demodulator captures and analyzes the wavelength drift signal reflected back from the FBG in real time. The traction drive module includes a high-precision servo motor, a reducer, and a rope wheel, responsible for providing axial tension to drive the mechanical structure's movement.

[0039] 3. Rope-driven closed-loop tension control method This invention employs the following integrated drive and sensing process to achieve rope-driven closed-loop tension control, including preprocessing and calibration models, designing tension feedback closed-loop control algorithms, and safety limit and self-diagnosis processes.

[0040] (1) Preprocessing and model calibration.

[0041] Before implementing control, it is necessary to establish a mapping relationship between optical signals and physical quantities: (2) Experiments were conducted to determine the tendon-like structure under different tensile forces. Center wavelength offset The linear proportionality coefficient was obtained by fitting. This refers to measurement sensitivity. Using a reference grating (which needs to be additionally placed within the target device) or a dual-wavelength difference method, the drift effect of ambient temperature changes on wavelength is eliminated, ensuring the purity of the tension calculation.

[0042] (2) Design a tension feedback closed-loop control algorithm.

[0043] The control system executes the following cycle using high-frequency sampling: The controller receives instructions from the host computer and sets the target tension value. The optical demodulation module acquires the wavelength signal of the FBG inside the composite tendon in real time and converts it into the current real tension according to the calibration model. and real-time deviation value Calculate the PID control parameters, including proportional (P), integral (I), and derivative (D). The proportional (P) can quickly respond to tension fluctuations, the integral (I) can eliminate steady-state errors caused by rope viscoelasticity and guide friction, and the derivative (D) can suppress oscillations caused by the hysteresis effect of the flexible rope. Execute motor drive control. The control algorithm outputs control quantities (such as PWM duty cycle or torque commands, which are determined according to the motor controller mode) to the servo motor, driving the rope wheel to rotate to compensate for tension deviations.

[0044] It should be noted that, in this embodiment of the invention, since the FBG sensor is located directly inside the rope, it senses the actual internal force in the middle or end section after passing through the guide mechanism. The control algorithm no longer estimates friction through complex physical models, but directly uses the force sensed by the sensor as feedback. This WYSIWYG mechanism greatly simplifies the control algorithm and improves system sensitivity, making it particularly suitable for dexterous hand grasping or exoskeleton compliance assistance requiring precise force feedback.

[0045] (3) Safety limit and self-diagnosis.

[0046] Real-time monitoring of wavelength offset, once If the set elastic limit threshold is exceeded, an emergency stop is immediately triggered to prevent damage to tendon-like or mechanical structures. Furthermore, if the demodulator detects an interruption in the optical signal or an abnormal reflection spectrum, the system automatically determines that the tendon is damaged, ensuring the safety of human-computer interaction.

[0047] 4. Integrated rope-driven sensing device Based on the aforementioned integrated drive and sensing tendon-like component, this invention can construct a rope-driven dexterous hand or exoskeleton system / device capable of complex motion coordination through the modular integration of multiple components.

[0048] (1) Quasi-distributed topology architecture with multiple components Because FBG supports wavelength multiplexing, fiber optic lines of multiple tendon-like components can be connected to different channels of the same high-frequency optical demodulator. By etching gratings with different center wavelengths on a single fiber, synchronous monitoring of the tension of multiple finger joints of a dexterous hand or multiple degrees of freedom of an exoskeleton can be achieved.

[0049] At the same time, because tendon-like materials have a very small bending radius, multiple components can pass through the narrow conduits / wiring frames in parallel through the palm of a dexterous hand or the back plate of an exoskeleton, without the need for independent configuration for each degree of freedom. This can greatly improve the integration density of the system, especially for dexterous hands in confined spaces.

[0050] (2) Multidimensional perception and coordination of dexterous hand / exoskeleton system Based on the above distributed architecture, such as Figure 4 As shown, the red lines represent schematic fiber optic segments. In dexterous hand applications, each finger utilizes an independent composite tendon-like component to drive the distal, mid, and proximal phalanges. This invention can etch gratings with different center wavelengths onto the fiber optics of the composite tendon-like component, enabling real-time acquisition of the actual internal forces of the distal, mid, and proximal phalangeal tendons, achieving cross-joint tension sensing. Addressing the nonlinear friction caused by conduit bending in long-path exoskeleton transmission, the system utilizes real tension data from multiple segments within the component to achieve decoupling and friction compensation, thereby enabling dynamic compensation at the control layer to ensure that the wearer's intentions are accurately translated into end-effector assistance.

[0051] (3) Multi-axis torque distribution and collaborative interactive control After acquiring tension information from a single tendon-like component, the central controller calculates and distributes the target torque of each drive motor based on feedback from each degree of freedom and in conjunction with the kinematic model. This enables multi-axis torque distribution, impedance control, or admittance control, giving the dexterous hand extremely high flexibility and interactive safety when grasping fragile objects or when the exoskeleton assists in human movement.

[0052] It should be noted that the core of this invention lies in realizing a tendon (rope) that integrates "drive-sensing," which solves the problem of difficulty in tension sensing without changing the existing rope-driven system. Those skilled in the art can make appropriate changes or modifications to the above embodiments without departing from the spirit and scope of this invention. For example, the sensing core material can be multimode fiber, micro / nano fiber, or polymer fiber (POF), combined with the principle of long-period grating (LPG) or fiber interferometer for sensing. Besides single-mode fiber, any material that can be integrated with a flexible rope to achieve integrated drive and sensing is acceptable. Furthermore, the optical fiber is not limited to an axial arrangement; multiple fibers can be asymmetrically woven into the load-bearing layer, simultaneously measuring the rope's bending direction and torque through differential signals. Moreover, the load-bearing fiber can be replaced with carbon fiber, liquid crystal polymer (LCP) fiber, or fine metal wire bundles to adapt to ultra-high loads or extreme high-temperature environments. For the coating layer, magnetic or thermally conductive particles can be doped into the polyimide coating layer to give the tendon-like structure magnetic field sensing or faster temperature response capabilities. In addition, the application scenarios of this invention can be extended to multiple industries. For example, in medical robots: ultra-fine drive ropes for minimally invasive surgical robots provide precise tactile feedback without electromagnetic interference within narrow body cavities; in major equipment monitoring: they serve as monitoring core materials for large cranes, cable-stayed bridges, and parachute rigging, enabling real-time monitoring of structural stress and fatigue damage; in flexible electronics and smart fabrics: these tendons are woven into smart clothing for motion capture of human joints and intelligent sensing for assistive exoskeletons; and in deep-sea / polar actuation: utilizing the low transmission loss and corrosion resistance of optical fibers, they provide tension feedback actuation for deep-sea remotely operated vehicles (ROVs) in extreme environments.

[0053] To further verify the effectiveness of this invention, the designed tendon-like component based on an FBG composite braided structure was experimentally tested, demonstrating its superior performance in both actuation and sensing compared to traditional methods. Specifically, a quasi-static tensile test was conducted on the composite tendon-like component using a universal testing machine to verify linearity and sensitivity. The results showed that the center wavelength offset exhibited extremely high linear correlation within a range of 0-500N. Furthermore, an anti-interference comparison experiment was performed, comparing the signal quality of a resistance strain gauge bridge and the component of this invention in an environment adjacent to a high-frequency driver of a servo motor. The experiment showed that the strain gauge bridge signal exhibited significant power frequency noise interference, while the FBG signal waveform of this invention was smooth.

[0054] In summary, compared with existing technologies such as tension measurement schemes and integrated "drive-sensing" schemes based on strain bridge deformation measurement, the present invention has the following main advantages; (1) The present invention designs an FBG-fiber composite braided structure, with the FBG sensor as the core axis, and integrates it with high-strength fiber (aramid or ultra-high molecular weight polyethylene) through a specific braiding process to achieve the integration of sensing and load-bearing / driving physical properties.

[0055] (2) This invention designs a wavelength modulation multiplexing sensing mechanism, which uses optical wavelength offset rather than resistance strain signal to measure the true tension inside the rope, solving the electromagnetic interference problem of the rope drive system in complex environments. Furthermore, by using wavelength multiplexing, gratings with different center wavelengths are etched on a single optical fiber, resulting in a tendon-like material with multidimensional sensing and coordination. This invention utilizes the wavelength modulation principle to completely shield the spatial electromagnetic noise generated by the high-power motor of the exoskeleton, improving the signal-to-noise ratio and sensing accuracy.

[0056] (3) The present invention designs a body-based sensing and friction self-compensation mechanism. By using multi-segment tension sensing units embedded inside the rope, the internal force of the transmission path is directly obtained, thereby achieving decoupling and friction compensation.

[0057] (4) This invention designs a multi-component integrated system, which consists of multiple composite tendon-like components to form a dexterous hand or exoskeleton rope-driven device and its control method with integrated quasi-distributed sensing capabilities. This invention eliminates all external sensors, and preliminary estimates indicate that the structural complexity of the palm and joint parts of the dexterous hand is reduced by more than 50%, and the cost is relatively low, making it easy to industrialize.

[0058] (5) Traditional tension measurement is either the tension at the motor end or requires an additional force measuring mechanism. This invention measures the real effective force in the rope acting on the actuator after the rope passes through a complex path. In theory, it can measure the entire length and the measurement position is real.

[0059] (6) This invention utilizes the high sampling frequency of optical demodulation combined with hysteresis-free braided stress transmission to enable the closed-loop control frequency to overcome the bottleneck of traditional flexible actuators and improve the dynamic response speed.

[0060] This invention can be an apparatus, method, and / or computer program product. A computer program product may include a computer-readable storage medium having computer-readable program instructions loaded thereon for causing a processor to implement various aspects of the invention.

[0061] The various embodiments of the present invention have been described above. These descriptions are exemplary and not exhaustive, and are not limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments. The terminology used herein is chosen to best explain the principles, practical application, or technical improvements to the embodiments in the market, or to enable others skilled in the art to understand the embodiments disclosed herein. The scope of the invention is defined by the appended claims.

Claims

1. A tendon-like structure based on a composite braided structure, characterized in that, This type of tendon uses a fiber Bragg grating as the sensing layer, which includes an optical fiber and an outer braided layer. The fiber core is engraved with grating segments of a set period, and the surface of the fiber is covered with a polymer coating. The braided layer and the optical fiber are cross-braided in multiple strands according to a preset braiding angle. By controlling the braiding angle, the axial tension can be transmitted linearly to the fiber Bragg grating in a proportional manner.

2. The tendon-like structure according to claim 1, characterized in that, It also includes load-bearing fibers arranged coaxially with the optical fiber and a protective layer for protecting the tendon-like structure.

3. The tendon-like structure according to claim 1, characterized in that, The weaving method is as follows: using aramid or ultra-high molecular weight polyethylene fibers as the axis of the grating core material, multiple strands are cross-woven according to a preset weaving angle.

4. A drive-sensing integrated rope-driven device, comprising: According to any one of claims 1 to 3, the tendon-like structure, optical demodulation unit, drive execution unit, and controller, wherein: One end of the tendon-like structure is connected to the drive source, and the other end is connected to the load side. The optical demodulation unit is used to emit a light beam toward the tendon-like structure and detect the wavelength offset reflected back by the fiber Bragg grating. The drive execution unit serves as the drive source, including a servo motor and a rope winding wheel; The controller calculates the actual tension inside the tendon-like structure based on the wavelength offset using a preset wavelength-tension mapping model, and uses this actual tension as a feedback signal to determine and adjust the output of the servo motor to drive the rope wheel to rotate in order to compensate for the tension deviation.

5. The apparatus according to claim 4, characterized in that, The tension deviation is obtained according to the following steps: The controller receives instructions from the host computer and sets the target tension value. ; The optical demodulation unit acquires the wavelength signal of the fiber Bragg grating inside the tendon-like structure in real time, and converts it into the current real tension according to the preset wavelength-tension mapping model. and real-time deviation value ; Calculate the PID control parameters, including the proportional parameter P, integral parameter I, and derivative parameter D; Based on the calculated PID control parameters, the control quantity is output to the servo motor to drive the rope wheel to rotate and compensate for tension deviation.

6. The apparatus according to claim 4, characterized in that, The wavelength-tension mapping model is calibrated according to the following steps: Establish the mapping relationship between optical signals and physical quantities: in, It is axial tension. It is the wavelength offset. It is the center wavelength of the fiber Bragg grating. For the strain of tendon-like materials, For the effective photosensitivity coefficient, B is the linear proportionality coefficient, and B is the intercept. Experiments were conducted to determine the tendon-like structure under different tensions. Center wavelength offset The linear proportionality coefficient was obtained by fitting. .

7. The apparatus according to claim 4, characterized in that, The optical demodulation unit is an optical demodulator. Multiple tendon-like fiber optic lines are connected to different channels of the same optical demodulator. By etching gratings with different center wavelengths on a single fiber, it is applied to the synchronous monitoring of tension in multiple finger joints of a dexterous hand or multiple degrees of freedom of an exoskeleton.

8. The apparatus according to claim 7, characterized in that, In dexterous hand applications, each finger uses an independent tendon-like structure to drive the distal, mid, and proximal phalanges, enabling real-time acquisition of the actual internal force of the distal, mid, and proximal phalangeal tendons to sense cross-joint tension.

9. The apparatus according to claim 7, characterized in that, After obtaining the tension information of a single tendon-like muscle, the controller calculates and allocates the target torque of each servo motor based on the feedback of each degree of freedom and in combination with the kinematic model, thereby realizing multi-axis torque distribution, impedance control or admittance control.

10. The apparatus according to claim 4, characterized in that, Also includes: When the wavelength offset is detected to exceed the set threshold or the reflection spectrum is abnormal, the drive execution unit is controlled to trigger an emergency stop.

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