Industrial camera optical system stability control method based on temperature compensation

Abstract

The invention relates to the field of industrial camera control, and discloses an industrial camera optical system stability control method based on temperature compensation, which comprises the following steps of: arranging temperature sensors to construct a temperature field distribution matrix so as to judge temperature data of different positions in an industrial camera, and constructing a thermal deformation compensation model; the deformation compensation module is used for outputting deformation compensation parameters and compensating optical system stability caused by temperature abnormity of the industrial camera, and finally a long-term temperature drift database is built to conduct model self-adaptive updating on the thermal deformation compensation model. Clear output images in the operation process of the industrial camera can be achieved in a temperature compensation mode, namely stability control is carried out on an optical system of the industrial camera, and the working efficiency and accuracy of the industrial camera are ensured.

Description

Technical Field

[0001] The present invention relates to the field of industrial camera control, and in particular to a method for controlling the stability of an industrial camera optical system based on temperature compensation. Background Art

[0002] Industrial cameras are image capture devices designed specifically for industrial applications. Compared to consumer-grade cameras (such as mobile phone cameras and digital cameras), they emphasize stability, reliability, accuracy, high speed, long life, and robust environmental adaptability. They are widely used in automated production lines, quality inspection, machine vision guidance, scientific research, medical imaging, security monitoring, and other fields. The core characteristics of industrial cameras are durability, high reliability, and stability, enabling continuous, stable operation over long periods of time with a low failure rate. Furthermore, precise image control and high-speed image acquisition and transmission are key features of industrial cameras.

[0003] Any slight change in an industrial camera's optical system can affect the performance of the program. For example, temperature fluctuations or mechanical stress can cause minute shifts in lens position, curvature, or refractive index, altering the effective focal length. In 3D vision, focal length changes directly affect triangulation accuracy. Micron-level translation or tilt of the camera's internal image sensor (CMOS / CCD) relative to the lens' optical axis can cause image distortion, field of view angle shifts, and principal point offsets. Even when repeatedly measuring the same object at the same location, if the optical system is unstable (e.g., internal state changes each time the camera is turned on or after a period of operation), the resulting image feature positions or 3D coordinates will be inconsistent. In industrial environments, temperature fluctuations are the most common, significant, and difficult-to-avoid factor affecting optical system stability. For example, thermal expansion and contraction of materials can affect focal length, while thermal effects, environmental heat generation, and self-heating of optical components can also contribute. Therefore, it is necessary to incorporate temperature compensation into the optical system stability control process for industrial cameras. A temperature-compensated optical system stability control method for industrial cameras is proposed. Summary of the Invention

[0004] The present invention overcomes the deficiencies of the prior art and provides a method for controlling the stability of an industrial camera optical system based on temperature compensation.

[0005] In order to achieve the above object, the technical solution adopted by the present invention is: A first aspect of the present invention provides a method for controlling the stability of an industrial camera optical system based on temperature compensation, comprising the following steps: Embed temperature sensors in industrial cameras and synchronously collect temperature data from different nodes in the industrial cameras through the temperature sensors to establish a temperature field distribution matrix; Combined with the temperature field distribution matrix, a thermal deformation compensation model is constructed in the target industrial camera; Based on the thermal deformation compensation model, the deformation compensation parameters required by the target industrial camera are output, and temperature compensation is performed on the target industrial camera according to the output image of the target industrial camera; A long-term temperature drift database is constructed, and the thermal deformation compensation model is adaptively updated based on the long-term temperature drift database.

[0006] Furthermore, in a preferred embodiment of the present invention, a temperature sensor is embedded in the industrial camera, and the temperature data of different nodes in the industrial camera are synchronously collected by the temperature sensor to establish a temperature field distribution matrix, specifically: An industrial camera requiring optical system stability control is calibrated as a target industrial camera, and a temperature sensor is obtained, wherein the temperature sensor is installed in the target industrial camera; Obtain the specifications of the target industrial camera and, based on the specifications, determine all locations in the target industrial camera where temperature sensors can be installed. Calibrate these locations as temperature sensor installation locations and simultaneously determine the heat conduction paths and mechanical deformation-sensitive locations of the target industrial camera. Determine, within all possible temperature sensor installation locations, a location that coincides with a heat conduction path and a mechanical deformation sensitive location of a target industrial camera, calibrate the location as a target installation location, and install a temperature sensor at each of the target installation locations; Control the operation of the industrial camera, and during the operation of the industrial camera, collect temperature data at the target installation location in real time through all installed temperature sensors, and calibrate it to collect temperature data in real time; Import all real-time collected temperature data into the control terminal for analysis, construct a timestamp, mark the target installation location as a node, align the real-time collected temperature data of different nodes based on the timestamp in the control terminal, and establish a temperature field distribution matrix based on the node position in the control terminal; The temperature field distribution matrix describes the real-time distribution status of the operating temperature at different positions of the target industrial camera.

[0007] Furthermore, in a preferred embodiment of the present invention, the thermal deformation compensation model is constructed in the target industrial camera in combination with the temperature field distribution matrix, specifically as follows: Based on the specifications of the target industrial camera, determine the controllable deformation compensation parameter range of different positions of the target industrial camera; The controllable deformation compensation parameter range includes the controllable deformation compensation parameter range of the target industrial camera internal parameters and external parameters; Based on the temperature field distribution matrix, the thermal strain tensor at different positions of the target industrial camera is calculated. Then, through finite element analysis, a mapping matrix between the thermal strain tensor and the controllable deformation compensation parameter range is established and calibrated as the thermal deformation mapping matrix. Based on the thermal deformation mapping matrix, an intrinsic parameter compensation model and an extrinsic parameter compensation model of the target industrial camera are constructed, wherein the intrinsic parameter compensation model is used to compensate for the stability of the optical system of the target industrial camera when working with a single camera, and the extrinsic parameter compensation model is used to compensate for the stability of the optical system of the target industrial camera when working with a binocular camera; The internal parameter compensation model and the external parameter compensation model are collectively referred to as the thermal deformation compensation model. The method for constructing the thermal deformation compensation model is to perform multivariate linear regression on the thermal deformation mapping matrix to output the coupling effect coefficients corresponding to different positions of the target industrial camera. The coupling effect coefficients are then combined to construct the heat transfer-structure coupling equations corresponding to different positions on the target industrial camera. By combining all the heat transfer-structure coupling equations, the thermal deformation compensation model can be constructed. Among them, the thermal deformation compensation model calculates the thermal strain tensor of the corresponding position according to the real-time temperature of different positions of the target industrial camera in the temperature field distribution matrix, thereby calculating the deformation compensation parameters corresponding to different thermal strain tensors, wherein the deformation compensation parameters are temperature parameters.

[0008] Furthermore, in a preferred embodiment of the present invention, the thermal deformation compensation model is used to output the deformation compensation parameters required by the target industrial camera, and temperature compensation is performed on the target industrial camera according to the output image of the target industrial camera, specifically: Run the target industrial camera, and during the operation of the target industrial camera, analyze the thermal deformation mapping matrix in combination with the real-time temperature data collected by the temperature sensor; Based on the thermal deformation mapping matrix, positions where the thermal strain tensor is greater than a preset value are determined and calibrated as a type of industrial camera compensation position. Based on the thermal deformation mapping matrix, a controllable deformation compensation parameter range corresponding to the type of industrial camera compensation position is output to obtain a type of industrial camera compensation position-controllable deformation compensation parameter range combination; Based on different combinations of the compensation position of a class of industrial cameras and the range of controllable deformation compensation parameters, the deformation compensation parameters of the compensation position of a class of industrial cameras are output through the thermal deformation compensation model and calibrated as a class of deformation compensation parameters; If there is a type of industrial camera compensation position, the image output by the target industrial camera is analyzed, and temperature compensation is performed on the target industrial camera based on the analysis result.

[0009] Furthermore, in a preferred embodiment of the present invention, the image output by the target industrial camera is analyzed, and temperature compensation is performed on the target industrial camera based on the analysis result, specifically: Determine whether the image output by the target industrial camera during operation is a 2D image or a 3D image; If the output image is a 2D image, the output image is calibrated as a 2D output image; if the output image is a 3D image, the output image is calibrated as a 3D output image; When there is a 2D output image, a type of deformation compensation parameter is called to perform temperature compensation on the target industrial camera, and the 2D output image is subjected to real-time dedistortion remapping processing in combination with the type of deformation compensation parameter; Generating a 2D output image after distortion correction in real time, and presetting a standard image of the 2D output image after distortion correction; The system calculates the similarity between the distortion-corrected 2D output image and the standard image in real time. When the similarity is greater than a preset value, it stops performing temperature compensation on the target industrial camera using a type of deformation compensation parameter. If a 3D output image exists, calling a type of deformation compensation parameter to perform temperature compensation on the target industrial camera, and combining the type of deformation compensation parameter to perform stereo reconstruction processing on the 3D output image; The 3D output image after stereo reconstruction is analyzed and a standard 3D output image is obtained. When the overlap between the 3D output image after stereo reconstruction and the standard 3D output image is greater than a preset value, temperature compensation of the target industrial camera using a type of deformation compensation parameter is stopped.

[0010] Furthermore, in a preferred embodiment of the present invention, the long-term temperature drift database is constructed, and the thermal deformation compensation model is adaptively updated in combination with the long-term temperature drift database, specifically: Obtain a reference object inside the target industrial camera, measure the actual values ​​of optical parameters in the industrial camera in real time based on the reference object, and calculate the temperature drift at different positions in the target industrial camera in combination with the temperature field distribution matrix; Obtain the operating time of the target industrial camera, and build a long-term temperature drift database based on the operating time of the target industrial camera and the temperature drift at different locations within the target industrial camera. Connecting the long-term temperature drift database with the thermal deformation compensation model, and presetting the update state of the thermal deformation compensation model, wherein the update state of the thermal deformation compensation model includes a regular update state and an emergency update state; The conventional update state is to update the temperature drift amount of the long-term temperature drift database in real time and preset a standard update number. If the real-time update number of the temperature drift amount in the long-term temperature drift database is greater than the standard update number, the data update of the thermal deformation compensation model is triggered; The data update of the thermal deformation compensation model is to dynamically adjust the learning rate of the thermal deformation compensation model in combination with the least squares method to achieve the update of the deformation compensation parameters output by the thermal deformation compensation model; The emergency update state is that if the deformation compensation parameters output by the thermal deformation compensation model exceed the corresponding controllable deformation compensation parameter range, it is equivalent to the conventional update state. Combined with the least squares method, the learning rate of the thermal deformation compensation model is dynamically adjusted to achieve the update of the deformation compensation parameters output by the thermal deformation compensation model.

[0011] A second aspect of the present invention further provides an industrial camera optical system stability control system based on temperature compensation, the industrial camera optical system stability control system comprising a memory and a processor, the memory storing an industrial camera optical system stability control method, and the industrial camera optical system stability control method, when executed by the processor, implementing the following steps: Embed temperature sensors in industrial cameras and synchronously collect temperature data from different nodes in the industrial cameras through the temperature sensors to establish a temperature field distribution matrix; Combined with the temperature field distribution matrix, a thermal deformation compensation model is constructed in the target industrial camera; Based on the thermal deformation compensation model, the deformation compensation parameters required by the target industrial camera are output, and temperature compensation is performed on the target industrial camera according to the output image of the target industrial camera; A long-term temperature drift database is constructed, and the thermal deformation compensation model is adaptively updated based on the long-term temperature drift database.

[0012] The present invention addresses the technical deficiencies in the background art and has the following beneficial effects: by deploying temperature sensors to construct a temperature field distribution matrix, which is used to determine temperature data at different locations within an industrial camera, a thermal deformation compensation model is constructed to output deformation compensation parameters to compensate for the stability of the optical system of the industrial camera caused by temperature anomalies. Finally, a long-term temperature drift database is constructed to adaptively update the thermal deformation compensation model. The present invention can achieve clear output images during the operation of the industrial camera through temperature compensation, thereby controlling the stability of its optical system and ensuring the efficiency and accuracy of the industrial camera. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, without paying any creative work, they can also obtain drawings of other embodiments based on these drawings.

[0014] Figure 1 A flow chart of a method for controlling the stability of an industrial camera optical system based on temperature compensation is shown; Figure 2A flow chart of a method for temperature compensation of a target industrial camera is shown; Figure 3 Shows the program view of the industrial camera optical system stability control system based on temperature compensation. DETAILED DESCRIPTION

[0015] In order to more clearly understand the above-mentioned objects, features and advantages of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be noted that, in the absence of conflict, the embodiments of the present application and the features therein can be combined with each other.

[0016] In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Therefore, the scope of protection of the present invention is not limited to the specific embodiments disclosed below.

[0017] Figure 1 A flow chart of a method for controlling the stability of an industrial camera optical system based on temperature compensation is shown, comprising the following steps: S102: embedding and distributing temperature sensors in the industrial camera, and synchronously collecting temperature data of different nodes in the industrial camera through the temperature sensors to establish a temperature field distribution matrix; S104: Based on the temperature field distribution matrix, a thermal deformation compensation model is constructed in the target industrial camera; S106: Outputting deformation compensation parameters required by the target industrial camera based on the thermal deformation compensation model, and performing temperature compensation on the target industrial camera according to the output image of the target industrial camera; S108: Constructing a long-term temperature drift database, and performing a model adaptive update on the thermal deformation compensation model in combination with the long-term temperature drift database.

[0018] Furthermore, in a preferred embodiment of the present invention, a temperature sensor is embedded in the industrial camera, and the temperature data of different nodes in the industrial camera are synchronously collected by the temperature sensor to establish a temperature field distribution matrix, specifically: An industrial camera requiring optical system stability control is calibrated as a target industrial camera, and a temperature sensor is obtained, wherein the temperature sensor is installed in the target industrial camera; Obtain the specifications of the target industrial camera, and based on the specifications of the target industrial camera, determine all locations in the target industrial camera where temperature sensors can be installed, calibrate them as temperature sensor installation locations, and simultaneously determine the heat conduction paths and mechanical deformation sensitive locations of the target industrial camera; Determine, within all possible temperature sensor installation locations, a location that coincides with a heat conduction path and a mechanical deformation sensitive location of a target industrial camera, calibrate the location as a target installation location, and install a temperature sensor at each of the target installation locations; Control the operation of the industrial camera, and during the operation of the industrial camera, collect temperature data at the target installation location in real time through all installed temperature sensors, and calibrate it to collect temperature data in real time; Import all real-time collected temperature data into the control terminal for analysis, construct a timestamp, mark the target installation location as a node, align the real-time collected temperature data of different nodes based on the timestamp in the control terminal, and establish a temperature field distribution matrix based on the node position in the control terminal; The temperature field distribution matrix describes the real-time distribution status of the operating temperature at different positions of the target industrial camera.

[0019] It should be noted that temperature sensors are used to collect operating temperatures at various locations within an industrial camera. This operating temperature can affect the stability of the camera's optical system, so after collecting the temperatures, a temperature field distribution matrix must be constructed to monitor the temperatures at various locations in real time. Not all locations can accommodate temperature sensors, so it is necessary to determine suitable locations for temperature sensors and identify the target industrial camera's heat conduction paths and mechanical deformation-sensitive locations. These locations require temperature sensors to be installed, as these locations are particularly temperature-sensitive within the camera. The temperature field distribution matrix describes the real-time distribution of operating temperatures at various locations within the target industrial camera, including the temperature distribution locations and values.

[0020] Furthermore, in a preferred embodiment of the present invention, the thermal deformation compensation model is constructed in the target industrial camera in combination with the temperature field distribution matrix, specifically as follows: Based on the specifications of the target industrial camera, determine the controllable deformation compensation parameter range of different positions of the target industrial camera; The controllable deformation compensation parameter range includes the controllable deformation compensation parameter range of the target industrial camera internal parameters and external parameters; Based on the temperature field distribution matrix, the thermal strain tensor at different positions of the target industrial camera is calculated. Then, through finite element analysis, a mapping matrix between the thermal strain tensor and the controllable deformation compensation parameter range is established and calibrated as the thermal deformation mapping matrix. Based on the thermal deformation mapping matrix, an intrinsic parameter compensation model and an extrinsic parameter compensation model of the target industrial camera are constructed, wherein the intrinsic parameter compensation model is used to compensate for the stability of the optical system of the target industrial camera when working with a single camera, and the extrinsic parameter compensation model is used to compensate for the stability of the optical system of the target industrial camera when working with a binocular camera; The internal parameter compensation model and the external parameter compensation model are collectively referred to as the thermal deformation compensation model. The method for constructing the thermal deformation compensation model is to perform multivariate linear regression on the thermal deformation mapping matrix to output the coupling effect coefficients corresponding to different positions of the target industrial camera. The coupling effect coefficients are then combined to construct the heat transfer-structure coupling equations corresponding to different positions on the target industrial camera. By combining all the heat transfer-structure coupling equations, the thermal deformation compensation model can be constructed. Among them, the thermal deformation compensation model calculates the thermal strain tensor of the corresponding position according to the real-time temperature of different positions of the target industrial camera in the temperature field distribution matrix, thereby calculating the deformation compensation parameters corresponding to different thermal strain tensors, wherein the deformation compensation parameters are temperature parameters.

[0021] It should be noted that if a temperature anomaly occurs within an industrial camera, thermal deformation may occur. The principle of temperature compensation in this case is to adjust for this thermal deformation and restore it to normal. The controllable deformation compensation parameter range is the temperature variation range, which is adjusted based on the different thermal deformations. The controllable deformation compensation parameter range includes the controllable deformation compensation parameter ranges for the target industrial camera's internal and external parameters. Compensating for internal parameters refers to deformation compensation for industrial cameras that capture 2D images, while compensating for external parameters refers to deformation compensation for industrial cameras that capture 3D stereo images. The thermal strain tensor is calculated at different locations on the target industrial camera and a thermal deformation mapping matrix is ​​constructed. This allows for convenient and rapid data integration and the construction of a thermal deformation compensation model. Based on the coupling coefficient, the target industrial camera selects deformation compensation parameters based on the thermal strain within the corresponding controllable deformation compensation parameter range to compensate for internal device deformation. Because optical systems are composed of multiple devices, devices within the system may deform when subjected to temperature anomalies. Temperature compensation can maintain stability and eliminate these deformations.

[0022] Furthermore, in a preferred embodiment of the present invention, the long-term temperature drift database is constructed, and the thermal deformation compensation model is adaptively updated in combination with the long-term temperature drift database, specifically: Obtain a reference object inside the target industrial camera, measure the actual values ​​of optical parameters in the industrial camera in real time based on the reference object, and calculate the temperature drift at different positions in the target industrial camera in combination with the temperature field distribution matrix; Obtain the operating time of the target industrial camera, and build a long-term temperature drift database based on the operating time of the target industrial camera and the temperature drift at different locations within the target industrial camera. Connecting the long-term temperature drift database with the thermal deformation compensation model, and presetting the update state of the thermal deformation compensation model, wherein the update state of the thermal deformation compensation model includes a regular update state and an emergency update state; The conventional update state is to update the temperature drift amount of the long-term temperature drift database in real time and preset a standard update number. If the real-time update number of the temperature drift amount in the long-term temperature drift database is greater than the standard update number, the data update of the thermal deformation compensation model is triggered; The data update of the thermal deformation compensation model is to dynamically adjust the learning rate of the thermal deformation compensation model in combination with the least squares method to achieve the update of the deformation compensation parameters output by the thermal deformation compensation model; The emergency update state is that if the deformation compensation parameters output by the thermal deformation compensation model exceed the corresponding controllable deformation compensation parameter range, it is equivalent to the conventional update state. Combined with the least squares method, the learning rate of the thermal deformation compensation model is dynamically adjusted to achieve the update of the deformation compensation parameters output by the thermal deformation compensation model.

[0023] It should be noted that through the deep coupling of the temperature drift database and the physical constraint incremental learning, the adaptive evolution capability of the thermal compensation model of the industrial camera is realized for the first time, which can solve the problem of accuracy degradation caused by material aging in traditional methods. In this application, the purpose of constructing a temperature drift database is to improve the output accuracy of the thermal deformation compensation model. Because after the industrial camera material ages, the previous temperature compensation value may not be applicable. Combined with the working time of the target industrial camera and the temperature drift at different positions in the target industrial camera, after constructing a long-term temperature drift database, the data update of the thermal deformation compensation model is realized, including regular update status and emergency update status. The benchmark reference objects inside the target industrial camera include but are not limited to zero-expansion ceramic targets or built-in calibration plates, and the measured optical parameters include but are not limited to focal length, baseline length, etc.

[0024] Figure 2 A flow chart of a method for temperature compensation of a target industrial camera is shown, comprising the following steps: S202: Outputting deformation compensation parameters required by the target industrial camera based on the thermal deformation compensation model, and performing temperature compensation on the target industrial camera according to an output image of the target industrial camera; S204: Analyze the image output by the target industrial camera, and perform temperature compensation on the target industrial camera based on the analysis result.

[0025] Furthermore, in a preferred embodiment of the present invention, the thermal deformation compensation model is used to output the deformation compensation parameters required by the target industrial camera, and temperature compensation is performed on the target industrial camera according to the output image of the target industrial camera, specifically: Run the target industrial camera, and during the operation of the target industrial camera, analyze the thermal deformation mapping matrix in combination with the real-time temperature data collected by the temperature sensor; Based on the thermal deformation mapping matrix, positions where the thermal strain tensor is greater than a preset value are determined and calibrated as a type of industrial camera compensation position. Based on the thermal deformation mapping matrix, a controllable deformation compensation parameter range corresponding to the type of industrial camera compensation position is output to obtain a type of industrial camera compensation position-controllable deformation compensation parameter range combination; Based on different combinations of the compensation position of a class of industrial cameras and the range of controllable deformation compensation parameters, the deformation compensation parameters of the compensation position of a class of industrial cameras are output through the thermal deformation compensation model and calibrated as a class of deformation compensation parameters; If there is a type of industrial camera compensation position, the image output by the target industrial camera is analyzed, and temperature compensation is performed on the target industrial camera based on the analysis result.

[0026] It should be noted that the thermal deformation mapping matrix is ​​analyzed. Since the thermal deformation compensation model calculates the thermal strain tensor at each target industrial camera location based on the real-time temperature at each location in the temperature field distribution matrix, and thus calculates the deformation compensation parameters corresponding to each thermal strain tensor, after obtaining the thermal strain tensor at the corresponding location from the thermal deformation mapping matrix, the deformation compensation parameters are output and used to perform temperature compensation for a specific industrial camera location. A specific industrial camera location is only output for locations where the thermal strain tensor exceeds a preset value. If the thermal strain tensor is less than the preset value, the deformation does not affect the stability of the industrial camera's optical system. In this case, temperature compensation is no longer necessary, and the target industrial camera is in good working condition.

[0027] Furthermore, in a preferred embodiment of the present invention, the image output by the target industrial camera is analyzed, and temperature compensation is performed on the target industrial camera based on the analysis result, specifically: Determine whether the image output by the target industrial camera during operation is a 2D image or a 3D image; If the output image is a 2D image, the output image is calibrated as a 2D output image; if the output image is a 3D image, the output image is calibrated as a 3D output image; When there is a 2D output image, a type of deformation compensation parameter is called to perform temperature compensation on the target industrial camera, and the 2D output image is subjected to real-time dedistortion remapping processing in combination with the type of deformation compensation parameter; Generating a 2D output image after distortion correction in real time, and presetting a standard image of the 2D output image after distortion correction; The system calculates the similarity between the distortion-corrected 2D output image and the standard image in real time. When the similarity is greater than a preset value, it stops performing temperature compensation on the target industrial camera using a type of deformation compensation parameter. If a 3D output image exists, calling a type of deformation compensation parameter to perform temperature compensation on the target industrial camera, and combining the type of deformation compensation parameter to perform stereo reconstruction processing on the 3D output image; The 3D output image after stereo reconstruction is analyzed and a standard 3D output image is obtained. When the overlap between the 3D output image after stereo reconstruction and the standard 3D output image is greater than a preset value, temperature compensation of the target industrial camera using a type of deformation compensation parameter is stopped.

[0028] It should be noted that the methods and verification approaches for temperature compensation of industrial cameras differ when outputting 2D or 3D output images. For 2D images, the effectiveness of a type of deformation compensation parameter must be determined in conjunction with real-time dedistortion and remapping. Temperature anomalies within industrial cameras can cause distortion in the output image due to optical system deformation. After temperature compensation, temperature compensation for the target industrial camera using the type of deformation compensation parameter is discontinued until the output image is free of distortion, meaning the image similarity exceeds a preset value. This similarity can be calculated by comparing image pixel values ​​and image overlap. Similarly, for stereo reconstruction of 3D output images, temperature compensation using the type of deformation compensation parameter is discontinued when the overlap between the reconstructed 3D output image and the standard 3D output image exceeds a preset value. This indicates that the target industrial camera has reached a stable optical system state after temperature compensation.

[0029] A second aspect of the present invention further provides an industrial camera optical system stability control system based on temperature compensation, the industrial camera optical system stability control system comprising a memory 31 and a processor 32. The memory 31 stores an industrial camera optical system stability control method. When the industrial camera optical system stability control method is executed by the processor 32, the following steps are implemented: Embed temperature sensors in industrial cameras and synchronously collect temperature data from different nodes in the industrial cameras through the temperature sensors to establish a temperature field distribution matrix; Combined with the temperature field distribution matrix, a thermal deformation compensation model is constructed in the target industrial camera; Based on the thermal deformation compensation model, the deformation compensation parameters required by the target industrial camera are output, and temperature compensation is performed on the target industrial camera according to the output image of the target industrial camera; A long-term temperature drift database is constructed, and the thermal deformation compensation model is adaptively updated based on the long-term temperature drift database.

[0030] The above are merely specific embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any modifications or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be based on the scope of protection of the claims.

Claims

1. A method for controlling the stability of an industrial camera optical system based on temperature compensation, characterized in that: The following steps are involved: Embed temperature sensors in industrial cameras and synchronously collect temperature data from different nodes in the industrial cameras through the temperature sensors to establish a temperature field distribution matrix; Combined with the temperature field distribution matrix, a thermal deformation compensation model is constructed in the target industrial camera; Based on the thermal deformation compensation model, the deformation compensation parameters required by the target industrial camera are output, and temperature compensation is performed on the target industrial camera according to the output image of the target industrial camera; A long-term temperature drift database is constructed, and the thermal deformation compensation model is adaptively updated based on the long-term temperature drift database.

2. The method for controlling the stability of an industrial camera optical system based on temperature compensation according to claim 1, wherein: The temperature sensor is embedded in the industrial camera and the temperature data of different nodes in the industrial camera are synchronously collected by the temperature sensor to establish a temperature field distribution matrix. Specifically, An industrial camera requiring optical system stability control is calibrated as a target industrial camera, and a temperature sensor is obtained, wherein the temperature sensor is installed in the target industrial camera; Obtain the specifications of the target industrial camera, and based on the specifications of the target industrial camera, determine all locations in the target industrial camera where temperature sensors can be installed, calibrate them as temperature sensor installation locations, and simultaneously determine the heat conduction paths and mechanical deformation sensitive locations of the target industrial camera; Determine, within all possible temperature sensor installation locations, a location that coincides with a heat conduction path and a mechanical deformation sensitive location of a target industrial camera, calibrate the location as a target installation location, and install a temperature sensor at each of the target installation locations; Control the operation of the industrial camera, and during the operation of the industrial camera, collect temperature data at the target installation location in real time through all installed temperature sensors, and calibrate it to collect temperature data in real time; Import all real-time collected temperature data into the control terminal for analysis, construct a timestamp, mark the target installation location as a node, align the real-time collected temperature data of different nodes based on the timestamp in the control terminal, and establish a temperature field distribution matrix based on the node position in the control terminal; The temperature field distribution matrix describes the real-time distribution status of the operating temperature at different positions of the target industrial camera.

3. The method for controlling the stability of an industrial camera optical system based on temperature compensation according to claim 1, wherein: The thermal deformation compensation model is constructed in the target industrial camera in combination with the temperature field distribution matrix, specifically: Based on the specifications of the target industrial camera, determine the controllable deformation compensation parameter range of different positions of the target industrial camera; The controllable deformation compensation parameter range includes the controllable deformation compensation parameter range of the target industrial camera internal parameters and external parameters; Based on the temperature field distribution matrix, the thermal strain tensor at different positions of the target industrial camera is calculated. Then, through finite element analysis, a mapping matrix between the thermal strain tensor and the controllable deformation compensation parameter range is established and calibrated as the thermal deformation mapping matrix. Based on the thermal deformation mapping matrix, an intrinsic parameter compensation model and an extrinsic parameter compensation model of the target industrial camera are constructed, wherein the intrinsic parameter compensation model is used to compensate for the stability of the optical system of the target industrial camera when working with a single camera, and the extrinsic parameter compensation model is used to compensate for the stability of the optical system of the target industrial camera when working with a binocular camera; The internal parameter compensation model and the external parameter compensation model are collectively referred to as the thermal deformation compensation model. The method for constructing the thermal deformation compensation model is to perform multivariate linear regression on the thermal deformation mapping matrix to output the coupling effect coefficients corresponding to different positions of the target industrial camera. The coupling effect coefficients are then combined to construct the heat transfer-structure coupling equations corresponding to different positions on the target industrial camera. By combining all the heat transfer-structure coupling equations, the thermal deformation compensation model can be constructed. Among them, the thermal deformation compensation model calculates the thermal strain tensor of the corresponding position according to the real-time temperature of different positions of the target industrial camera in the temperature field distribution matrix, thereby calculating the deformation compensation parameters corresponding to different thermal strain tensors, wherein the deformation compensation parameters are temperature parameters.

4. The method for controlling the stability of an industrial camera optical system based on temperature compensation according to claim 1, wherein: Based on the thermal deformation compensation model, the deformation compensation parameters required by the target industrial camera are output, and the temperature compensation of the target industrial camera is performed according to the output image of the target industrial camera. Specifically, Run the target industrial camera, and during the operation of the target industrial camera, analyze the thermal deformation mapping matrix in combination with the real-time temperature data collected by the temperature sensor; Based on the thermal deformation mapping matrix, positions where the thermal strain tensor is greater than a preset value are determined and calibrated as a type of industrial camera compensation position. Based on the thermal deformation mapping matrix, a controllable deformation compensation parameter range corresponding to the type of industrial camera compensation position is output to obtain a type of industrial camera compensation position-controllable deformation compensation parameter range combination; Based on different combinations of the compensation position of a class of industrial cameras and the range of controllable deformation compensation parameters, the deformation compensation parameters of the compensation position of a class of industrial cameras are output through the thermal deformation compensation model and calibrated as a class of deformation compensation parameters; If there is a type of industrial camera compensation position, the image output by the target industrial camera is analyzed, and temperature compensation is performed on the target industrial camera based on the analysis result.

5. The method for controlling the stability of an industrial camera optical system based on temperature compensation according to claim 4, wherein: The image output by the target industrial camera is analyzed, and temperature compensation is performed on the target industrial camera based on the analysis result, specifically: Determine whether the image output by the target industrial camera during operation is a 2D image or a 3D image; If the output image is a 2D image, the output image is calibrated as a 2D output image; if the output image is a 3D image, the output image is calibrated as a 3D output image; When there is a 2D output image, a type of deformation compensation parameter is called to perform temperature compensation on the target industrial camera, and the 2D output image is subjected to real-time dedistortion remapping processing in combination with the type of deformation compensation parameter; Generating a 2D output image after distortion correction in real time, and presetting a standard image of the 2D output image after distortion correction; The system calculates the similarity between the distortion-corrected 2D output image and the standard image in real time. When the similarity is greater than a preset value, it stops performing temperature compensation on the target industrial camera using a type of deformation compensation parameter. If a 3D output image exists, calling a type of deformation compensation parameter to perform temperature compensation on the target industrial camera, and combining the type of deformation compensation parameter to perform stereo reconstruction processing on the 3D output image; The 3D output image after stereo reconstruction is analyzed and a standard 3D output image is obtained. When the overlap between the 3D output image after stereo reconstruction and the standard 3D output image is greater than a preset value, temperature compensation of the target industrial camera using a type of deformation compensation parameter is stopped.

6. The method for controlling the stability of an industrial camera optical system based on temperature compensation according to claim 1, wherein: The long-term temperature drift database is constructed, and the thermal deformation compensation model is adaptively updated based on the long-term temperature drift database, specifically: Obtain a reference object inside the target industrial camera, measure the actual values ​​of optical parameters in the industrial camera in real time based on the reference object, and calculate the temperature drift at different positions in the target industrial camera in combination with the temperature field distribution matrix; Obtain the operating time of the target industrial camera, and build a long-term temperature drift database based on the operating time of the target industrial camera and the temperature drift at different locations within the target industrial camera. Connecting the long-term temperature drift database with the thermal deformation compensation model, and presetting the update state of the thermal deformation compensation model, wherein the update state of the thermal deformation compensation model includes a regular update state and an emergency update state; The conventional update state is to update the temperature drift amount of the long-term temperature drift database in real time and preset a standard update number. If the real-time update number of the temperature drift amount in the long-term temperature drift database is greater than the standard update number, the data update of the thermal deformation compensation model is triggered; The data update of the thermal deformation compensation model is to dynamically adjust the learning rate of the thermal deformation compensation model in combination with the least squares method to achieve the update of the deformation compensation parameters output by the thermal deformation compensation model; The emergency update state is that if the deformation compensation parameters output by the thermal deformation compensation model exceed the corresponding controllable deformation compensation parameter range, it is equivalent to the conventional update state. Combined with the least squares method, the learning rate of the thermal deformation compensation model is dynamically adjusted to achieve the update of the deformation compensation parameters output by the thermal deformation compensation model.

7. An industrial camera optical system stability control system based on temperature compensation, characterized in that: The industrial camera optical system stability control system includes a memory and a processor, wherein the memory stores an industrial camera optical system stability control method program. When the industrial camera optical system stability control method program is executed by the processor, the industrial camera optical system stability control method steps as described in any one of claims 1 to 6 are implemented.

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