Space truss module of integrated embedded optical fiber self-sensing composite material

Abstract

The invention provides a space truss module of an integrated embedded optical fiber self-sensing composite material. The space truss module is composed of a modular truss, an intelligent sensing layer, an optical fiber grating sensor, an optical fiber grating demodulation instrument and a data processing system. The intelligent sensing layer is formed by embedding a fiber grating sensor into a fiber reinforced composite material at a specific angle and is tightly attached to the surface of the modular truss, so that the strain, temperature and form and position state of the truss structure are monitored in real time. In the truss module, sensor wavelength change data is read through a fiber grating demodulation instrument, temperature compensation and strain conversion are carried out in combination with a data processing system, and the structural state and the health state of the space truss are evaluated. The device has the characteristics of high sensitivity, high temperature resistance, electromagnetic interference resistance and the like, is simple in structure, light in weight and high in reliability, can provide real-time monitoring and early warning support for on-orbit assembly and maintenance of a large space structure, and has remarkable engineering application value.

Description

Technical Field

[0001] The present invention relates to the field of satellite mechanical structure and status monitoring technology, and in particular to a space truss module integrating an embedded optical fiber self-sensing composite material. The embedded optical fiber self-sensing composite material can realize real-time monitoring of the space truss structure, has the advantages of high sensitivity, high precision, lightweight, and strong environmental resistance. It is integrated with the space truss structure and is suitable for on-orbit assembly and status monitoring of large space structures. Background Art

[0002] With the increasing complexity and scale of space missions, the design and monitoring technology of space structures are facing severe challenges. Traditional truss structure monitoring methods mostly rely on mechanical electronic sensors or optical detection equipment, which have problems such as high cost, high complexity, and poor applicability. Especially for large truss structures, traditional monitoring methods are difficult to meet the needs of real-time and accurate monitoring. Therefore, the present invention proposes a truss module based on embedded optical fiber self-sensing composite materials, which uses optical fiber Bragg grating sensors to bury the composite materials to form an intelligent sensing layer to monitor the structural status of the truss in real time, providing reliable technical support for on-orbit assembly and maintenance. Summary of the Invention

[0003] 1. Purpose: The purpose of the embodiments of the present invention is to provide a method for real-time, high-precision monitoring of the state of a spatial truss structure, which solves the problems of high cost, high complexity, and poor applicability of traditional truss structure monitoring systems.

[0004] 2. Technical solution: An embodiment of the present invention provides a space truss module integrating embedded optical fiber self-sensing composite materials, which is composed of a modular truss, a composite material intelligent sensing layer of embedded optical fiber Bragg grating sensors, an optical fiber Bragg grating demodulation instrument and a data processing system.

[0005] Furthermore, the modular truss is constructed from lightweight, high-rigidity materials, typically aluminum alloy or carbon fiber composites, to meet the stringent structural strength and weight requirements of aerospace applications. The intelligent sensing layer is constructed from a fiber-reinforced composite material (such as carbon fiber, glass fiber, or aramid fiber) and a polymer matrix (such as epoxy resin or polyimide). Fiber Bragg grating (FBG) sensors are embedded within the layer through a fiber implantation and protection process, forming a highly sensitive, high-temperature-resistant, and electromagnetically resistant intelligent sensing layer suitable for space environments.

[0006] Furthermore, the intelligent sensing layer is tightly bonded to the surface of the modular truss using high-strength adhesives or mechanical connections, ensuring a tight bond between the sensor and the composite material. This allows for real-time monitoring of the truss structure's strain, temperature, and shape and position changes, ensuring its health and stability in extreme environments. A fiber Bragg grating (FBG) demodulator reads wavelength variations from the FBG sensor. The data processing system analyzes these wavelength variations and eliminates temperature effects, enabling precise monitoring of the truss structure's status.

[0007] Furthermore, an intelligent sensing layer is placed along the axial and transverse directions of the truss members, covering high-stress areas and critical nodes, capturing the strain changes during the truss's unfolding, folding, and load-bearing processes. To maintain weight control and adapt to the size and scale of the spatial truss, the thickness of the intelligent sensing layer ranges from 0.5mm to 2mm.

[0008] Furthermore, a fiber Bragg grating demodulation instrument is used to read the wavelength change data of the FBG sensor in real time, and a data processing system is used to perform temperature compensation and strain conversion to evaluate the structural state and health status of the space truss.

[0009] 3. Beneficial effects: In summary, the present invention realizes a space truss structure with integrated intelligent sensing composite materials, which can achieve real-time monitoring of the space truss structure without significantly increasing the structural mass. The intelligent sensing composite materials are low in cost, simple in structure, highly reliable, durable, can be reused, and are suitable for space service environments. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 This is a schematic diagram of the truss module in the unfolded state.

[0011] Figure 2 This is a schematic diagram of the truss module in the folded state.

[0012] Figure 3 It is a brief schematic diagram of the intelligent sensing layer embedded with fiber grating sensors.

[0013] Figure 4 This is a schematic diagram of the layout of the intelligent sensing layer embedded with fiber grating sensors.

[0014] Figure 1 Chinese: 1. Modular truss.

[0015] Figure 1 Chinese: 2. Intelligent perception layer.

[0016] Figure 3 Chinese: 3. Fiber Bragg grating sensor.

[0017] Figure 3 Chinese: 4. Fiber-reinforced composite materials. DETAILED DESCRIPTION

[0018] The present invention will be further described below with reference to the accompanying drawings and implementation examples.

[0019] The present invention provides a truss module based on an embedded optical fiber self-sensing composite material. The truss module consists of a modular truss 1, an embedded optical fiber Bragg grating sensor intelligent sensing layer 2, an optical fiber Bragg grating demodulation instrument and a data processing system.

[0020] Please refer to Figure 3 During the production process of the intelligent sensing layer 2, the fiber Bragg grating sensor 3 is embedded in the fiber reinforced composite material 4 at a specific angle, and corresponding protection is performed at the port, and the layer is cured and formed using a vacuum bag, autoclave or other curing method.

[0021] The intelligent sensing layer 2 is composed of a fiber-reinforced composite material 4 and a fiber Bragg grating sensor 3. The fiber-reinforced composite material can include carbon fibers, glass fibers, or aramid fibers, while the polymer matrix is ​​a high-strength, high-temperature-resistant material such as epoxy resin, polyimide, or cyanate ester. Micron- or nanometer-sized carbon powder, carbon nanoparticles, and carbon nanotubes can also be used as reinforcements to further enhance the composite's mechanical properties and sensing capabilities.

[0022] After the intelligent sensing layer 2 is fabricated, the fiber Bragg grating sensor 3 needs to be calibrated on the ground to determine the relationship between the fiber Bragg grating wavelength variation and applied strain and temperature changes. This process involves calculating the photoelastic coefficient and thermal expansion coefficient, effectively eliminating the influence of ambient temperature changes on the measurement results.

[0023] Please refer to Figure 1 and Figure 2 , the change in optical fiber wavelength in the folded and fully unfolded states of the truss module is measured on the ground to provide baseline data for subsequent real-time monitoring.

[0024] Please refer to Figure 1 After the intelligent sensing layer 2 is calibrated, it is tightly attached to the surface of the modular truss 1 through high-strength adhesive or mechanical connection to ensure efficient transmission of strain between the sensor and the spatial truss structure.

[0025] When the truss module enters the space, the fiber Bragg grating demodulation instrument reads the wavelength change data in the optical fiber in real time, and imports the obtained data into the data processing system to eliminate the wavelength change caused by the ambient temperature change, so as to accurately obtain the expansion state of the truss module (such as Figure 1 By comparing this with ground-based measurement data, the deployment status of the space truss module can be determined.

[0026] Through the above embodiments, the truss module of the application can realize real-time and high-precision monitoring of the truss structure state, and provides reliable technical support for on-orbit assembly and maintenance of large space structures.

Claims

1. A space truss module with integrated embedded optical fiber self-sensing composite material, characterized in that include: A modular truss (1); an intelligent sensing layer (2), the intelligent sensing layer (2) being integrated or closely attached to the modular truss (1) and being composed of a fiber-reinforced composite material (4) having a built-in fiber Bragg grating sensor (3); and a fiber Bragg grating demodulation instrument, the instrument being connected to the fiber Bragg grating sensor (3) to demodulate its wavelength change in real time. and a data processing system connected to the fiber Bragg grating demodulation instrument for analyzing the demodulated wavelength change data and monitoring the structural state of the space truss module.

2. The module according to claim 1, characterized in that: The modular truss (1) is made of a lightweight, high-rigidity material, which is an aluminum alloy or a carbon fiber composite material.

3. The module according to claim 1, characterized in that: The fiber-reinforced composite material (4) of the intelligent sensing layer (2) comprises a reinforcement selected from carbon fiber, glass fiber or aramid fiber, and a polymer matrix selected from epoxy resin, polyimide or cyanate resin.

4. The module according to claim 3, characterized in that: The fiber-reinforced composite material (4) further comprises micron-scale or nano-scale carbon powder, carbon nanoparticles or carbon nanotubes as reinforcing supplementary materials to enhance the mechanical properties and sensory capabilities of the composite material.

5. The module according to claim 1, characterized in that: The intelligent sensing layer (2) is tightly adhered to the surface of the modular truss (1) by means of a high-strength adhesive or a mechanical connection, so as to ensure efficient transmission of strain between the sensor and the modular truss (1) structure.

6. The module according to claim 1, characterized in that: The intelligent sensing layer (2) is arranged along the axial direction and / or transverse direction of the modular truss (1) rods to cover high stress areas and key nodes, thereby capturing the strain changes of the truss during the unfolding, folding and load-bearing processes.

7. The module according to claim 1 or 6, characterized in that: The thickness of the intelligent sensing layer (2) is 0.5 mm to 2 mm.

8. The module according to claim 1, characterized in that: The data processing system performs temperature compensation and strain conversion calculations, and accurately monitors the state of the truss structure by analyzing wavelength changes and eliminating temperature effects, thereby evaluating the structure and health status of the spatial truss module.

9. The module according to claim 1, characterized in that: The fiber Bragg grating sensor (3) is calibrated before being integrated into the intelligent sensing layer (2). The calibration is used to determine the relationship between the wavelength change of the fiber Bragg grating and the applied strain and temperature change. This process involves the calculation of the photoelastic coefficient and the thermal expansion coefficient.

10. The module according to claim 1, characterized in that: The variation of the optical fiber wavelength of the modular truss (1) in the folded state and the fully unfolded state is measured in advance on the ground, and the variation provides baseline data for subsequent on-orbit real-time monitoring, which is used to judge the unfolding state of the space truss module.

11. A method for state monitoring using a space truss module of an integrated embedded optical fiber self-sensing composite material according to any one of claims 1 to 10, characterized in that The following steps are involved: After the space truss module is deployed, the wavelength change data of the fiber Bragg grating sensor (3) on the module is read in real time by its fiber Bragg grating demodulation instrument; the acquired wavelength change data is transmitted to its data processing system; the data processing system analyzes and processes the received wavelength change data, and the processing includes temperature compensation and strain conversion to calculate the wavelength drift caused by the change of the structural state of the truss module; the calculated wavelength drift is compared with the preset baseline data; and the current deployment state or structural health status of the space truss module is judged based on the comparison result.

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