An on-line detection method and system for fiber optic slack length

Abstract

The present invention discloses an on-line detection method and system for the surplus length of an optical fiber, which obtains a first image set at the pay-off end of the optical fiber, and obtains first image information and a corresponding first clock from the first image set; the first image set corresponds to the field of view of the area where the optical fiber enters the extruder; obtains a second image set at the take-up end of the sleeve, and obtains second image information and third image information from the second image set; the second image set corresponds to the field of view of the area where the colored optical fiber is taken up; obtains the speed of the pay-off end of the optical fiber, calculates the length of the optical fiber according to the first time delay, and obtains the length of the sleeve according to the first image information and the second image information; calculates and obtains the surplus length of the optical fiber from the length of the optical fiber and the length of the sleeve. The present invention utilizes vision system technology to perform the surplus length analysis of the optical fiber, can realize the image state information in the overall production process, and can provide the analysis and utilization of more characteristic information for the optical fiber sheathing production system.

Description

Technical Field

[0001] The present invention belongs to the technical field of optical cable production, and particularly relates to an on-line detection method and system for fiber surplus length. Background Art

[0002] The generation of fiber surplus length enables the optical cable to have superior mechanical and physical properties. During the transportation or construction and laying of the optical cable, when the environmental temperature changes or there is an external force, the optical cable has a certain amount of telescopic redundancy. The generation of fiber surplus length enables the optical fiber itself to be free from external forces or reduces the external force to an acceptable level when the optical cable undergoes telescopic changes. The size of the fiber surplus length is an important indicator for measuring the production process of the optical cable, and the most important control parameter in the sheathing process is the surplus length of the optical fiber in the sleeve. Accurately obtaining the result of the fiber surplus length becomes the key. The detection and measurement of the fiber surplus length usually include means such as manual intercept measurement and on-line measurement.

[0003] On-line measurement uses a non-contact on-line fiber surplus length measurement system to synchronously measure the fiber surplus length during the production of fiber sheathing. Its basic measurement principle is based on the laser Doppler velocity measurement principle: when an object passes through a laser beam at a certain speed, the beam will undergo a scattering phenomenon to generate scattered light, and the scattered light will produce a Doppler frequency shift, and the magnitude of the frequency shift is proportional to the speed of the object passing through the laser beam. Calculate the forward speed of the optical fiber (or tube) from the detected Doppler frequency data, and further convert it into the length ΔLf and ΔLT passed through per unit time, and the fiber surplus length can be obtained. One is installed between the fiber pay-off reel and the extruder to measure the length Lf of the optical fiber or the fiber ribbon, and the other is installed after the main traction to measure the length of the loose tube. After processing the two measurement data, the on-line fiber surplus length can be obtained. In fact, the sleeve after passing through the main traction will further contract due to the temperature drop, and there is a large gap from the surplus length value of the final product.

[0004] Currently, in the prior art, there are various technologies for the detection of fiber surplus length. In fact, the production process of fiber sheathing is a dynamically changing process, and the final surplus length is jointly determined by multiple factors. Obtaining the surplus length by acquiring the speed at a certain stage in the production process is a method that is separated from manual measurement, but it cannot comprehensively reflect the situation of the fiber surplus length in each stage of the secondary sheathing production line, nor can it finely analyze the key adjustment parameters in the surplus length adjustment: the relationship between the temperature, speed difference, and traction tension and the fiber surplus length.

[0005] With the development of image-based vision technology, there is currently no application of image vision technology for detecting the surplus length under the overall production state, nor has it achieved fine image analysis and parameter analysis to establish the relationship between the surplus length detection result and the surplus length control factors, so as to realize the detection of the fiber surplus length and assist in improving the measurement accuracy of the fiber surplus length. Summary of the Invention

[0006] Therefore, in view of at least one of the above defects or improvement requirements of the prior art, the present invention provides an on-line optical fiber surplus length detection method and system, which adopts a processing method of a vision measurement system plus a controller, enabling automatic detection of the optical fiber surplus length in the production of optical fiber sheathing and capable of collecting more image information including factors affecting the surplus length for feature analysis.

[0007] The present invention discloses an on-line optical fiber surplus length detection method, characterized in that the method comprises the following steps:

[0008] Obtain a first image set at the optical fiber pay-off end, and obtain first image information and a corresponding first clock from the first image set; the first image set corresponds to the field of view of the area where the optical fiber enters the extrusion machine.

[0009] Obtain a second image set at the sheathed optical fiber take-up end, and obtain second image information and third image information from the second image set; the second image set corresponds to the field of view of the sheathed optical fiber take-up area.

[0010] The second image information is the information obtained in response to the first clock, and the third image information is the information obtained in response to the first clock plus a first time delay.

[0011] Obtain the speed of the optical fiber pay-off end, calculate the optical fiber length according to the first time delay, and obtain the sheathed tube length according to the second image information and the third image information; calculate and obtain the optical fiber surplus length from the optical fiber length and the sheathed tube length.

[0012] Further, the second image information and the third image information are image information of the sheathed optical fiber after winding with a winding state.

[0013] Further, the method further comprises: collecting the second image information and the third image information at a plurality of first time delays, establishing an image feature sample, and analyzing and obtaining a correction value of the optical fiber surplus length due to further stable shrinkage of the sheathed tube over time.

[0014] Further, the method further comprises: obtaining the state information of the optical fiber entering the extrusion machine from the first image set, and generating control information for a guide wheel arranged at the front end of the extrusion machine according to the state information.

[0015] Further, the control information is the jitter information of the guide wheel, which controls the jitter of the optical fiber caused by the optical fiber pay-off speed.

[0016] The present invention also discloses an on-line optical fiber surplus length detection system, characterized in that the system comprises:

[0017] The first vision acquisition system is arranged at the optical fiber pay-off end to obtain the first image set of the area where the optical fiber enters the extruder; obtain the first image information and the corresponding first clock from the first image set and send them to the controller;

[0018] The second vision acquisition system is arranged at the sheathing take-up end to obtain the second image set of the area where the colored optical fiber is taken up; obtain the second image set of the sheathing take-up end, and obtain the second image information from the second image set according to the first control instruction; obtain the third image information from the second image set according to the second control instruction; send the second image information and the third image information to the controller;

[0019] The controller controls the first vision acquisition system and the second vision acquisition system and interacts with the control system of the colored optical fiber production equipment; the controller generates the first control instruction according to the first clock, generates the second control instruction according to the first clock and the first time delay, and sends it to the second vision acquisition system; obtain the speed of the optical fiber pay-off end from the control system of the colored optical fiber production equipment, calculate the optical fiber length according to the first time delay, and obtain the sheathing length according to the second image information and the third image information; calculate and obtain the surplus optical fiber length from the optical fiber length and the sheathing length.

[0020] Further, the second image information and the third image information are the image information of the colored optical fiber in the wound state after winding.

[0021] Further, the controller generates a third control instruction and sends it to the second vision acquisition system to collect the second image information and the third image information at multiple first time delays, establish an image feature sample, and analyze and obtain the surplus optical fiber length correction value due to the further stable shrinkage of the plastic sheathing over time.

[0022] Further, the first vision acquisition system obtains the state information of the optical fiber entering the extruder from the first image set, generates the control information of the guide wheel arranged at the front end of the extruder according to the state information, and sends it to the controller.

[0023] Further, the control information is the jitter information of the guide wheel, which controls the jitter of the optical fiber caused by the optical fiber pay-off speed.

[0024] Generally speaking, compared with the prior art through the above technical solutions of the inventive concept of the present invention, the following beneficial effects can be achieved:

[0025] (1) The present invention proposes a method for collecting image information in the production of colored optical fibers using a visual acquisition system, and analyzing and calculating the optical fiber surplus length information using the image information, which can intelligently collect information in the production process, can generate an image acquisition instruction through the controller of the visual system using the image and the corresponding clock, and can collect multiple image data to extract sufficient image information for optical fiber surplus length analysis.

[0026] (2) The present invention obtains the information after the sleeve is wound through image analysis. During the overall production process of the sheathing process, the sleeve undergoes alternating hot and cold water in multiple stages. In fact, after winding, it will further shrink due to temperature cooling, which affects the final result of the optical fiber surplus length. The present invention further extracts the image of the sleeve after winding for further analysis, analyzes the number of turns and the winding thickness information therein, and further calculates and obtains the sleeve length information, so as to reflect the optical fiber surplus length information closer to the production result.

[0027] (3) In the present invention, by setting a visual acquisition system in the secondary colored optical fiber production equipment, it is further possible to perform image acquisition on the state of the optical fiber incorporated into the extruder, monitor the optical fiber jitter caused by the excessive speed of the pay-off end, so that the visual acquisition system can monitor the state in advance, and can make the guide wheel jitter to maintain the consistency of the optical fiber incorporated into the extruder, thereby helping to maintain the stability of the surplus length.

[0028] (4) In the present invention, the collected image information is further used to establish a feature information library, collect the influence of associated water temperature, etc. on the optical fiber sheathing tube, and establish a feature library related to the influencing factors of the optical fiber surplus length to help perform surplus length adjustment analysis in the process. Brief Description of the Drawings

[0029] Figure 1 is a schematic flow chart of an on-line optical fiber surplus length detection method implemented according to the present invention;

[0030] Figure 2 is a schematic structural diagram of an on-line optical fiber surplus length detection system implemented according to the present invention. Detailed Embodiments

[0031] In order to make the objectives, technical solutions and advantages of the present invention clearer and more understandable, the present invention will be further described in detail below with reference to the drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0032] Such as Figure 1As shown, according to one embodiment of the present invention, an on-line detection method for the surplus length of an optical fiber is disclosed, characterized in that the method comprises the following steps:

[0033] Obtain a first image set at the fiber pay-off end, and obtain first image information and the corresponding first clock from the first image set; the first image set corresponds to the field of view of the area where the optical fiber enters the extruder.

[0034] The above-mentioned first image information is specifically the state information of the optical fiber entering the extruder. Collecting the image of the pay-off end, and the image using vision can help to save the multi-dimensional information in the secondary sheathing production process. First, the collected image includes the state information of the optical fiber, that is, before entering the extruder. Especially when the optical fibers are banded or stranded into the extruder, whether there is large jitter or bending of the optical fibers, and whether the state information between multiple optical fibers is normal. Generate a banding correction signal for the guide wheel based on the collected information to ensure the consistency of the surplus length of multiple optical fibers in production. As one implementation manner of the present invention, the banding correction signal is the jitter information of the guide wheel, which helps the jittering optical fiber to return to normal and controls the uneven surplus length caused by the jitter of the optical fiber due to the pay-off speed of the optical fiber.

[0035] Among them, when each image information is obtained, the corresponding clock information is also saved. Saving and recording the clock information helps to select the corresponding time period for periodic image comparison and analysis, obtain the calculation information of the surplus length of multiple optical fibers, and help analyze the fluctuation information of the overall surplus length uniformity in the production stage.

[0036] Among them, obtain the first clock, that is, select the corresponding time from the image information to facilitate synchronously obtaining the information at the sleeve end, and calculate the surplus length of the optical fiber by conveniently measuring the sleeve information after the corresponding time delay.

[0037] Obtain a second image set at the sleeve take-up end, and obtain second image information and third image information from the second image set; the second image set corresponds to the field of view of the colored optical fiber take-up area; the second image information is the information obtained in response to the first clock, and the third image information is the information obtained in response to the first clock plus the first time delay.

[0038] The above-mentioned second image information and third image information are specifically the state information of the colored optical fiber take-up area. By collecting images of the take-up end, visual images can help preserve multi-dimensional information during the secondary sheathing production process. First, the collected images include the state information of the sheathing, that is, the state information of the sheathing before entering the winding take-up end device and after winding, so that the collected image information can reflect the state information of the colored optical fiber after winding. For example, the winding state and the number of winding turns extracted from the second image information to the winding state and the number of winding turns extracted from the third image information can be used to obtain the winding length of the sheathing in the clock cycle of the first time delay to record the actual winding length. Compared with other methods of calculating the sheathing length by calculating the sheathing speed, the actual information of thermal expansion and contraction of the sheathing in multiple different states is not considered, making it impossible to accurately obtain the length information of the sheathing further.

[0039] Furthermore, obtain the speed of the optical fiber pay-off end, calculate the optical fiber length according to the first time delay, and obtain the sheathing length according to the second image information and the third image information; calculate and obtain the optical fiber surplus length from the optical fiber length and the sheathing length.

[0040] As one of the preferred embodiments of the present invention, the second image information and the third image information are image information of the colored optical fiber with a winding state after winding. In the state of the colored optical fiber after winding, in other embodiments, the sheathing tube can be marked, and the mark is identified in the time delay information of the collected image.

[0041] As one of the preferred embodiments of the present invention, collect multiple image information at multiple time delays, establish an image feature sample, and analyze and obtain the optical fiber surplus length correction value due to the further stable contraction of the sheathing tube over time.

[0042] Multiple groups of images can be taken of the number of turns state of the sheathing tube after winding, an image feature sample is established, and the image feature values in the image sample are analyzed, mainly for the state of the sheathing tube after stable contraction under further cooling. For example, call a specific calculation length of the sheathing tube, obtain multiple calculation lengths after accumulating a calculation interval, add them up to obtain the current theoretical value, and then compare it with the length information calculated from the actual image information collected after multiple calculation lengths of time to obtain the surplus length correction value after the cooling and stable contraction state. In short, through the analysis of the specific image information of the sheathing tube, multi-dimensional information of the optical fiber surplus length in the production process is obtained.

[0043] As Figure 2 shown in

[0044] A visual acquisition system disposed at least at the optical fiber pay-off end and the sleeve take-up end. Among them, the above visual acquisition system includes at least one set of cameras, which are arranged around the field of view area to acquire multiple image information of the field of view area, and each set of visual acquisition systems includes a visual processor.

[0045] Among them, the first visual acquisition system is disposed at the optical fiber pay-off end to obtain a first image set of the area where the optical fiber enters the extruder; in combination with the residual length detection method, the visual processor of the first visual acquisition system obtains the first image information and the corresponding first clock from the first image set and sends them to the controller.

[0046] Among them, the second visual acquisition system is disposed at the sleeve take-up end to obtain a second image set of the area where the colored optical fiber is taken up; obtain the second image set of the sleeve take-up end.

[0047] In combination with the residual length detection method, obtain the second image information from the second image set according to the first control instruction; obtain the third image information from the second image set according to the second control instruction; send the second image information and the third image information to the controller.

[0048] The controller controls the first visual acquisition system and the second visual acquisition system and interacts with the control system of the colored optical fiber production equipment; the controller generates a first control instruction according to the first clock, generates a second control instruction according to the first clock and the first time delay, and sends it to the second visual acquisition system; obtains the speed of the optical fiber pay-off end from the control system of the colored optical fiber production equipment, calculates the optical fiber length according to the first time delay, and obtains the sleeve length according to the second image information and the third image information; calculates and obtains the optical fiber residual length from the optical fiber length and the sleeve length.

[0049] Among them, as a preferred embodiment of the present invention, the cameras are arranged at multiple points around the field of view to acquire information in multiple dimensions.

[0050] Among them, the control program of the above detection system is implemented by a separate controller and is not incorporated into the control system of the production equipment to reduce the burden on the control system of the production equipment, and a large amount of data image information analysis can be executed in the separate controller.

[0051] In several embodiments provided by the present invention, it should be understood that the disclosed system can be implemented in other ways. For example, the system embodiments described above are merely illustrative. For example, the division of the above modules is only a logical function division, and there may be other division methods in actual implementation. For example, multiple modules or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point, the displayed or discussed coupling or direct coupling or communication connection to each other can be through some service interfaces, and the indirect coupling or communication connection of the system or module can be in an electrical or other form.

[0052] The module described as a separation component may or may not be physically separated. The component shown as a module may or may not be a physical module, that is, it may be located in one place or distributed across multiple network modules. Some or all of the modules can be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0053] In addition, each functional module in various embodiments of the present invention can be integrated into one processing module, or each module can exist physically alone, or two or more modules can be integrated into one module. The above-mentioned integrated module can be implemented in the form of hardware or in the form of a software functional module.

[0054] If the integrated module is implemented in the form of a software functional module and sold or used as an independent product, it can be stored in a computer-readable memory. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or all or part of this technical solution, can be embodied in the form of a software product. This computer software product is stored in a memory and includes several instructions to enable a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods described in various embodiments of the present invention. And the aforementioned memory includes: USB flash drive, read-only memory (ROM), random access memory (RAM), mobile hard disk, magnetic disk, or optical disc and other various media that can store program codes.

[0055] The above are only exemplary embodiments of the present disclosure and should not be used to limit the scope of the present disclosure. That is, any equivalent changes and modifications made in accordance with the teachings of the present disclosure still fall within the scope covered by the present disclosure. Those skilled in the art will readily think of other embodiments of the present disclosure after considering the specification and practicing the present disclosure herein. The present invention aims to cover any variations, uses, or adaptations of the present disclosure that follow the general principles of the present disclosure and include common general knowledge or conventional technical means in the technical field not described in the present disclosure. The specification and embodiments are only regarded as exemplary, and the scope and spirit of the present disclosure are defined by the claims.

[0056] The technical features of the above embodiments can be combined arbitrarily. For the sake of brevity of description, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered as within the scope described in this specification.

[0057] The content described in this specification is only an illustration of the present invention. Those skilled in the technical field to which the present invention pertains can make various modifications or supplements to the specific embodiments described, or use similar ways for substitution, as long as they do not deviate from the content of this specification of the present invention or exceed the scope defined by this claims, and shall fall within the protection scope of the present invention.

Claims

1. An on-line detection method for the surplus length of an optical fiber, characterized in that, the method comprises the following steps: Obtain a first image set at the pay-off end of the optical fiber, and obtain first image information and a corresponding first clock from the first image set; the first image set corresponds to the field of view of the area where the optical fiber enters the extrusion machine; Obtain a second image set at the take-up end of the sleeve, and obtain second image information and third image information from the second image set; the second image set corresponds to the field of view of the area where the colored optical fiber is taken up; The second image information is the information obtained in response to the first clock, and the third image information is the information obtained in response to the first clock plus a first time delay; Obtain the speed of the pay-off end of the optical fiber, calculate the length of the optical fiber according to the first time delay, and obtain the length of the sleeve according to the second image information and the third image information; calculate and obtain the surplus length of the optical fiber from the length of the optical fiber and the length of the sleeve.

2. The on-line detection method for the surplus length of an optical fiber according to claim 1, characterized in that, The second image information and the third image information are image information of the colored optical fiber in a wound state after winding.

3. The on-line detection method for the surplus length of an optical fiber according to claim 2, characterized in that, The method further comprises: collecting second image information and third image information at multiple first time delays, establishing an image feature sample, and analyzing and obtaining a correction value for the surplus length of the optical fiber due to further stable shrinkage of the plastic sleeve over time.

4. The on-line detection method for the surplus length of an optical fiber according to claim 3, characterized in that, The method further comprises: obtaining the state information of the optical fiber entering the extrusion machine from the first image set, and generating control information for a guide wheel arranged at the front end of the extrusion machine according to the state information.

5. The on-line detection method for the surplus length of an optical fiber according to claim 4, characterized in that, The control information is the jitter information of the guide wheel, and controls the jitter of the optical fiber caused by the pay-off speed of the optical fiber.

6. An on-line detection system for the surplus length of an optical fiber, characterized in that, the system comprises: A first vision acquisition system, arranged at the pay-off end of the optical fiber, to obtain a first image set of the area where the optical fiber enters the extrusion machine; obtain first image information and a corresponding first clock from the first image set, and send them to the controller; A second vision acquisition system, arranged at the take-up end of the sleeve, to obtain a second image set of the area where the colored optical fiber is taken up; obtain the second image set of the take-up end of the sleeve, obtain second image information from the second image set according to a first control instruction; obtain third image information from the second image set according to a second control instruction; send the second image information and the third image information to the controller; A controller that controls the first vision acquisition system and the second vision acquisition system and interacts with the control system of the colored optical fiber production equipment; the controller generates the first control instruction according to the first clock, generates the second control instruction according to the first clock and the first time delay, and sends it to the second vision acquisition system; obtains the speed of the fiber pay-off end from the control system of the colored optical fiber production equipment, calculates the fiber length according to the first time delay, and obtains the sleeve length according to the second image information and the third image information; calculates and obtains the fiber surplus length from the fiber length and the sleeve length.

7. The on-line fiber surplus length detection system according to claim 6, wherein, the second image information and the third image information are image information of the colored optical fiber after winding with a winding state.

8. The on-line fiber surplus length detection system according to claim 7, wherein, the controller generates a third control instruction and sends it to the second vision acquisition system, acquires the second image information and the third image information at multiple first time delays, establishes an image feature sample, and analyzes and obtains a fiber surplus length correction value due to further stable shrinkage of the plastic sleeve over time.

9. The on-line fiber surplus length detection system according to claim 8, wherein, the first vision acquisition system obtains the state information of the optical fiber entering the extruder from the first image set, generates control information for the guide pulley arranged at the front end of the extruder according to the state information, and sends it to the controller.

10. The on-line fiber surplus length detection system according to claim 9, wherein, the control information is the jitter information of the guide pulley, and controls the jitter of the optical fiber caused by the fiber pay-off speed.

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