Temperature field information acquisition method, device and system based on point cloud correction

Abstract

The application provides a temperature field information acquisition method, device and system based on point cloud correction. The application provides a temperature field information acquisition method, device and system based on point cloud correction. The method comprises the following steps: measuring laser point cloud data of a measured object to obtain direction information, distance information and reflected light intensity information of the measured object; obtaining a preliminary emissivity of the measured object according to the reflected light intensity information; determining a surface angle of the measured object according to the direction information and the distance information; correcting the preliminary emissivity through the surface angle of the measured object; and obtaining temperature field information of the measured object according to the emissivity of each point on the surface of the measured object, radiation intensity data and distance information. Since the emissivity and distance are both considered when calculating the temperature field information, and the emissivity and distance are both calculated based on the laser point cloud data, the obtained emissivity and distance are more accurate, and the accuracy of the finally obtained temperature field information is higher.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of temperature measurement, and in particular to a temperature field information acquisition method, device and system based on point cloud correction. BACKGROUND

[0002] The existing temperature measurement methods mainly include contact type temperature measurement and non-contact type temperature measurement. The contact type temperature measurement is accurate, but is time-consuming and labor-consuming, and is only suitable for continuous temperature monitoring of key positions, and cannot realize large-scale temperature measurement. The non-contact type temperature measurement mainly uses a single-point thermocouple and a regional infrared thermal imaging technology to realize temperature measurement, and is more convenient and efficient than the contact type temperature measurement.

[0003] The infrared thermal imaging temperature measurement mainly realizes temperature detection by measuring the thermal radiation intensity released by an object to the surrounding environment. The thermal radiation intensity is closely related to several factors in addition to the temperature of the object, such as the surface emissivity of the object and the distance of the object. The current thermal infrared imaging temperature measurement does not consider all factors, resulting in low accuracy of the temperature measurement results. SUMMARY

[0004] The present application provides a temperature field information acquisition method, device and system based on point cloud correction, to solve the defect that the current thermal infrared imaging temperature measurement does not consider all factors, resulting in low accuracy of the temperature measurement results.

[0005] In a first aspect, the present application provides a temperature field information acquisition method based on point cloud correction, which comprises:

[0006] acquiring laser point cloud data of a measured object collected by a point cloud sensor; wherein the laser point cloud data comprises direction information, distance information and reflected light intensity information of each point on the surface of the measured object;

[0007] obtaining a preliminary emissivity of each point on the surface of the measured object according to the reflected light intensity information of each point on the surface of the measured object;

[0008] determining a surface angle of the measured object according to the direction information and the distance information of each point on the surface of the measured object; wherein the surface angle is an included angle between a normal direction of the measured object and a preset shooting direction of the point cloud sensor, and the point cloud sensor is used to collect the laser point cloud data of the measured object;

[0009] correcting the preliminary emissivity of each point on the surface of the measured object according to the surface angle of the measured object, to obtain an emissivity result of each point on the surface of the measured object;

[0010] acquiring radiation intensity data of each point on the surface of the measured object;

[0011] According to the emissivity result, the radiation intensity data and the distance information of each point on the surface of the measured object, the temperature field information of the measured object is calculated.

[0012] According to the temperature field information acquisition method based on point cloud correction provided by the application, the laser point cloud data of the measured object is acquired, comprising:

[0013] The laser signal is respectively emitted to each point on the surface of the measured object, and the measurement signal returned from each point on the surface of the measured object is received.

[0014] For each point on the surface of the measured object, the direction information, the distance information and the reflected light intensity information of the point are acquired according to the measurement signal of the point.

[0015] According to the temperature field information acquisition method based on point cloud correction provided by the application, the preliminary emissivity of each point on the surface of the measured object is obtained according to the reflected light intensity information of each point on the surface of the measured object, comprising:

[0016] According to the reflected light intensity information of each point on the surface of the measured object, the reflectivity of each point on the surface of the measured object is calculated.

[0017] It is determined whether the measured object is a non-transparent object, and after it is determined that the measured object is a non-transparent object, the preliminary emissivity of each point on the surface of the measured object is calculated according to the corresponding relationship between the reflectivity and the emissivity of the non-transparent object.

[0018] According to the temperature field information acquisition method based on point cloud correction provided by the application, the surface angle of the measured object is determined according to the direction information and the distance information of each point on the surface of the measured object, comprising:

[0019] According to the direction information and the distance information of each point on the surface of the measured object, the surface contour information of the measured object is acquired.

[0020] According to the surface contour information of the measured object, the normal direction of the measured object is determined.

[0021] The included angle between the normal direction of the measured object and the preset shooting direction of the point cloud sensor is taken as the surface angle of the measured object.

[0022] According to the temperature field information acquisition method based on point cloud correction provided by the application, the preliminary emissivity of each point on the surface of the measured object is corrected according to the surface angle of the measured object, comprising:

[0023] If the surface angle of the measured object is within a preset angle threshold range, the preliminary emissivity is taken as the first emissivity;

[0024] If the surface angle of the measured object is outside the preset angle threshold range, an emissivity corresponding to the surface angle of the current measured object is determined from a pre-constructed surface angle-emissivity relationship curve, and taken as the first emissivity.

[0025] The first emissivity is taken as the emissivity result.

[0026] According to the present application, a temperature field information acquisition method based on point cloud correction is provided, and the preliminary emissivity of each point on the surface of the measured object is corrected according to the surface angle of the measured object, including:

[0027] If the surface angle of the measured object is within a preset angle threshold range, the preliminary emissivity is taken as the first emissivity;

[0028] If the surface angle of the measured object is outside the preset angle threshold range, an emissivity corresponding to the surface angle of the current measured object is determined from a pre-constructed surface angle-emissivity relationship curve, and taken as the first emissivity.

[0029] An optical image of the measured object is acquired.

[0030] According to the optical image, texture and material information of the measured object is determined.

[0031] According to a preset corresponding relationship between texture and material information and emissivity, an emissivity corresponding to the texture and material information of the current measured object is determined, and taken as the second emissivity.

[0032] The first emissivity is verified by using the second emissivity, and an emissivity result is determined according to a verification result.

[0033] In a second aspect, the present application further provides a temperature field information acquisition device based on point cloud correction, and the device includes:

[0034] A first acquisition module is configured to acquire laser point cloud data of a measured object collected by a point cloud sensor, wherein the laser point cloud data includes direction information, distance information and reflected light intensity information of each point on the surface of the measured object.

[0035] A first processing module is configured to obtain a preliminary emissivity of each point on the surface of the measured object according to the reflected light intensity information of each point on the surface of the measured object.

[0036] The second processing module is configured to determine a surface angle of the measured object according to the direction information and the distance information of each point on the surface of the measured object, wherein the surface angle is an included angle between a normal direction of the measured object and a preset shooting direction of the point cloud sensor.

[0037] The third processing module is configured to correct the preliminary emissivity of each point on the surface of the measured object according to the surface angle of the measured object, so as to obtain the emissivity result of each point on the surface of the measured object.

[0038] The second acquisition module is configured to acquire the radiation intensity data of each point on the surface of the measured object.

[0039] The fourth processing module is configured to calculate the temperature field information of the measured object according to the emissivity result, the radiation intensity data and the distance information of each point on the surface of the measured object.

[0040] In a third aspect, the present application further provides a temperature field information acquisition system based on point cloud correction, which comprises a point cloud sensor, a thermal imaging sensor and a data processing device, wherein the point cloud sensor and the thermal imaging sensor are connected with the data processing device.

[0041] The point cloud sensor is configured to collect laser point cloud data of a measured object.

[0042] The thermal imaging sensor is configured to collect radiation intensity data of each point on the surface of the measured object.

[0043] The data processing device is configured to acquire the laser point cloud data of the measured object collected by the point cloud sensor, wherein the laser point cloud data comprises direction information, distance information and reflected light intensity information of each point on the surface of the measured object; to obtain a preliminary emissivity of each point on the surface of the measured object according to the reflected light intensity information of each point on the surface of the measured object; to determine a surface angle of the measured object according to the direction information and the distance information of each point on the surface of the measured object, wherein the surface angle is an included angle between a normal direction of the measured object and a preset shooting direction of the point cloud sensor; to correct the preliminary emissivity of each point on the surface of the measured object according to the surface angle of the measured object, so as to obtain an emissivity result of each point on the surface of the measured object; to acquire radiation intensity data of each point on the surface of the measured object; and to calculate temperature field information of the measured object according to the emissivity result, the radiation intensity data and the distance information of each point on the surface of the measured object.

[0044] According to the temperature field information acquisition system based on point cloud correction provided by the present application, the system further comprises a visible light sensor, and the visible light sensor is configured to collect a visible light image of the measured object.

[0045] The data processing device is further configured to determine whether the surface angle of the measured object is within a preset angle threshold range, and if the surface angle of the measured object is within the preset angle threshold range, take the preliminary emissivity as the first emissivity; if the surface angle of the measured object is outside the preset angle threshold range, determine the emissivity corresponding to the surface angle of the current measured object from a pre-constructed surface angle-emissivity relationship curve, and take the emissivity as the first emissivity; acquire a visible light image of the measured object; determine the texture and material information of the measured object according to the visible light image; determine the emissivity corresponding to the texture and material information of the current measured object according to a preset texture and material information-emissivity correspondence relationship, and take the emissivity as the second emissivity; verify the first emissivity by using the second emissivity, and determine the emissivity result according to the verification result.

[0046] In a fourth aspect, the present application further provides an electronic device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the steps of the temperature field information acquisition method based on point cloud correction according to any one of the above aspects when executing the program.

[0047] The temperature field information acquisition method, device and system based on point cloud correction provided by the present application can obtain the direction information, distance information and reflected light intensity information of the measured object by measuring the laser point cloud data of the measured object, obtain the preliminary emissivity of the measured object according to the reflected light intensity information, determine the surface angle of the measured object according to the direction information and distance information, and correct the preliminary emissivity by the surface angle of the measured object. Finally, the temperature field information of the measured object is calculated according to the emissivity result, radiation intensity data and distance information of each point on the surface of the measured object. Since the emissivity and distance are considered when calculating the temperature field information, the factors considered are more comprehensive, and the emissivity and distance are both calculated in real time based on the laser point cloud data, so that the obtained emissivity and distance are more accurate, and the finally obtained temperature field information is more accurate. BRIEF DESCRIPTION OF DRAWINGS

[0048] In order to more clearly illustrate the technical solutions in the present application or prior art, the following will briefly introduce the drawings needed in the embodiments or prior art description. Obviously, the drawings in the following description are some embodiments of the present application, and those skilled in the art can also obtain other drawings according to these drawings without creative labor.

[0049] Figure 1 is a flowchart of the temperature field information acquisition method based on point cloud correction provided by the present application;

[0050] Figure 2is a schematic diagram of the collection principle of laser point cloud data and radiation intensity data of the measured object;

[0051] Figure 3 is a schematic diagram of the surface angle of the measured object;

[0052] Figure 4 is a schematic diagram of the relationship curve between the surface angle and the emissivity;

[0053] Figure 5 is a schematic diagram of the collection principle of laser point cloud data, radiation intensity data and visible light image of the measured object;

[0054] Figure 6 is a schematic diagram of the principle of obtaining temperature field information based on a point cloud sensor and a thermal imaging sensor;

[0055] Figure 7 is a schematic diagram of the principle of obtaining temperature field information based on a point cloud sensor, a thermal imaging sensor and a visible light sensor;

[0056] Figure 8 is a schematic diagram of the structure of the temperature field information acquisition device based on point cloud correction provided by the application;

[0057] Figure 9 is a schematic diagram of the structure of the electronic device provided by the application. DETAILED DESCRIPTION

[0058] To make the objectives, technical solutions and advantages of the present application clearer, the technical solutions in the present application will be described clearly and completely below with reference to the drawings in the present application. Obviously, the described embodiments are some embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0059] Figure 1 The temperature field information acquisition method based on point cloud correction provided by the embodiments of the present application is shown, and the method comprises the following steps:

[0060] Step 110: acquiring laser point cloud data of a measured object collected by a laser point cloud sensor; wherein the laser point cloud data comprises direction information, distance information and reflected light intensity information of each point on the surface of the measured object.

[0061] Specifically, the laser point cloud data of the measured object is acquired, comprising:

[0062] First, a laser signal is respectively emitted to each point on the surface of the measured object, and a measurement signal returned from each point on the surface of the measured object is received; in this embodiment, the laser point cloud data of the measured object is acquired by a point cloud sensor, specifically by a laser radar, as shown inFigure 2 As shown, at a certain moment, the laser radar 210 emits a laser signal to the measured object 2, and obtains a measurement signal returned by the measured object 2.

[0063] Then, according to the measurement signal, the direction information, the distance information and the reflected light intensity information of each point on the surface of the measured object 2 are obtained.

[0064] In view of the way of distance measurement of the traditional laser range finder, when the distance changes, it needs to be re-measured and set, and is only suitable for distance measurement of individual points, and when facing area measurement, it is very time-consuming and laborious. The distance between the measured object and the sensor obtained by the laser radar is more convenient and flexible.

[0065] Step 120: obtaining the preliminary emissivity of each point on the surface of the measured object according to the reflected light intensity information of each point on the surface of the measured object.

[0066] Specifically, the preliminary emissivity of each point on the surface of the measured object is obtained according to the reflected light intensity information of each point on the surface of the measured object, including:

[0067] Firstly, according to the reflected light intensity information of each point on the surface of the measured object, the reflectivity of each point on the surface of the measured object can be calculated.

[0068] Then, it is determined whether the measured object is a non-transparent object. After it is determined that the measured object is a non-transparent object, the preliminary emissivity of each point on the surface of the measured object is calculated according to the corresponding relationship between the reflectivity and the emissivity of the non-transparent object.

[0069] In view of the fact that when the laser signal is emitted to the measured object, part of the energy is absorbed by the object, part of the energy is transmitted out of the object, and part of the energy is reflected back. For non-transparent objects, the reflectivity and the emissivity are almost normalized, i.e. the sum of the reflectivity and the emissivity is equal to 1, so the emissivity of the measured object can be preliminarily evaluated by the reflectivity.

[0070] Step 130: determining the surface angle of the measured object according to the direction information and the distance information of each point on the surface of the measured object; wherein the surface angle is the included angle between the normal direction of the measured object and the preset shooting direction of the point cloud sensor.

[0071] Specifically, the surface angle of the measured object is determined according to the direction information and the distance information of each point on the surface of the measured object, including:

[0072] Firstly, according to the direction information and the distance information of each point on the surface of the measured object, the point cloud data of the region can be formed, and then the surface contour information of the measured object is obtained.

[0073] Then, according to the surface profile information of the measured object, the normal direction of the measured object is determined, that is, the direction perpendicular to the surface of the measured object, as shown by the dashed arrow in FIG. 2. Figure 2

[0074] The angle between the normal direction of the measured object and the shooting direction of the point cloud sensor is obtained to obtain the surface angle of the measured object. The surface angle of the object can be seen in FIG. 3. Figure 3 Figure 3 The angle a in FIG. 3 is the corresponding surface angle at the current shooting angle.

[0075] Step 140: According to the surface angle of the measured object, the preliminary emissivity of each point on the surface of the measured object is corrected to obtain the emissivity result of each point on the surface of the measured object.

[0076] Specifically, according to the surface angle of the measured object, the preliminary emissivity of each point on the surface of the measured object is corrected, including:

[0077] If the surface angle of the measured object is within the preset angle threshold range, the preliminary emissivity is taken as the first emissivity;

[0078] If the surface angle of the measured object is outside the preset angle threshold range, the emissivity corresponding to the current surface angle of the measured object is determined from the pre-constructed relationship curve between the surface angle and the emissivity, and is taken as the first emissivity.

[0079] The first emissivity is taken as the emissivity result.

[0080] For example, for the measured object 1 whose surface is perpendicular to the lidar 210, the reflectivity can be directly used for the calculation of the emissivity, but for the measured object 2 with a certain angle, the reflection intensity information obtained by the lidar 210 may be underestimated, and the preliminary emissivity calculated by the reflectivity needs to be corrected.

[0081] In actual application process, an angle threshold range can be set, such as -10° to 10°. Within this angle range, since the shooting inclination angle of the measured object and the lidar is small, the reflectivity can be directly used for the calculation of the preliminary emissivity. When the surface angle is not within the above-mentioned angle threshold range, it indicates that the shooting inclination angle of the measured object and the lidar is large, and at this time, the preliminary emissivity calculated by the reflectivity has a large error, and the preliminary emissivity needs to be corrected.

[0082] ​​Of course, in the scene with high precision requirement, the angle threshold can also be set as 0°, the surface angle is 0°, which indicates that the surface of the measured object is perpendicular to the shooting direction, at this time, the emissivity can be directly calculated through the reflectivity, that is, the preliminary emissivity can be directly used, and for the case that the surface angle is not 0°, it indicates that the surface of the measured object is not perpendicular to the shooting direction, at this time, the preliminary emissivity needs to be corrected according to the surface angle information.

[0083] When correcting the preliminary emissivity, the embodiment is realized through the pre-constructed relationship curve between the surface angle and the emissivity, as shown in the curve Figure 4 , there are multiple corresponding relationships between the surface angle and the emissivity in the curve, the corresponding emissivity can be found from the above relationship curve according to the current surface angle, and the emissivity is taken as the first emissivity, that is, the corrected emissivity result.

[0084] It is considered that the emissivity of the object surface and the distance have a very significant influence on the temperature measurement result. Therefore, the embodiment determines the emissivity of the object surface and the distance to improve the accuracy of the temperature measurement result.

[0085] For the distance measurement, the existing technology usually uses a laser range finder to obtain the distance between the object and the measurement device, but when the distance between the object and the measurement device changes, the laser range finder position needs to be re-arranged and the distance needs to be re-determined, and this method is only suitable for distance measurement of individual points and cannot realize distance measurement of a region, which has the problems of complicated ranging process and small application range. For this, the embodiment uses a point cloud sensor to measure the distance, scans the measured object through the point cloud sensor, obtains the laser point cloud data of the measured object, and then obtains the distance information of the measured object, which is more convenient, and the scanning process of the point cloud sensor can realize distance measurement of a region.

[0086] For the determination of the emissivity of the object surface, the existing technology generally measures specific samples in the laboratory through special equipment, which cannot be normally applied in actual temperature measurement scenes, and has the problem of small application range. For this, the embodiment uses the reflection light intensity information in the above obtained laser point cloud data to obtain the preliminary emissivity, and uses the direction information and distance information in the laser point cloud data to determine the surface angle of the measured object, and corrects the preliminary emissivity through the surface angle, so as to obtain a more accurate emissivity result, and realizes the emissivity correction in the actual temperature measurement scene.

[0087] Step 150: Obtain the radiation intensity data of each point on the surface of the measured object.

[0088] Referring to FIG. 1, Figure 2The radiation intensity data of the measured object is acquired by the thermal imaging sensor 220. In use, the view angles of the point cloud sensor and the thermal imaging sensor need to overlap as much as possible, and the correspondence between the pixels of the two sensors needs to be obtained through calibration to ensure the reliability of data acquisition.

[0089] Step 160: According to the emissivity result of each point on the surface of the measured object, the radiation intensity data and the distance information, the temperature field information of the measured object is calculated.

[0090] Since the calculation formula of the radiation intensity is as follows:

[0091]

[0092] Wherein, ε is the emissivity of the measured object, c is the speed of light, h is the Planck constant, k is the Boltzmann constant, λ is the wavelength, λ1 is the upper limit value of the wavelength, λ2 is the lower limit value of the wavelength, L is the thermal radiation intensity of the measured object, ω is the distance between the measured object and the sensor, k m is the atmospheric absorption coefficient, and T is the temperature of the measured object.

[0093] In the case where the emissivity, distance and thermal radiation intensity are determined, the temperature data of the measured object can be obtained. Since the present embodiment measures each point on the measured object, the temperature information of each point on the measured object, i.e. the temperature field information of the measured object, can be obtained.

[0094] More preferably, in order to ensure that the emissivity result of the measured object is accurate and reliable during temperature measurement, the present embodiment further adds a verification link for the first emissivity. Specifically, according to the surface angle of the measured object, the preliminary emissivity of each point on the surface of the measured object is corrected, including:

[0095] Firstly, it is judged whether the surface angle of the measured object is within a preset angle threshold range. If the surface angle of the measured object is within the preset angle threshold range, the preliminary emissivity is taken as the first emissivity.

[0096] If the surface angle of the measured object is outside the preset angle threshold range, the emissivity corresponding to the surface angle of the current measured object is determined from the pre-constructed relationship curve between the surface angle and the emissivity, and is taken as the first emissivity.

[0097] Then, the visible light image of the measured object is acquired; as shown in the figure, the visible light image can be obtained by the visible light sensor 510. Figure 5 The visible light image can be obtained by the visible light sensor 510.

[0098] Then, according to the visible light image, the texture and material information of the measured object is determined; in fact, through the visible light image, two parts of information can be obtained, one part is the color information of the measured region, which can assist in the segmentation of the point cloud data, and the measured object can be accurately segmented from the background environment; the other part is the texture and material information of the measured object, which is used to assist in analyzing the material of the measured object.

[0099] Then, according to the preset correspondence between the texture and material information and the emissivity, the emissivity corresponding to the texture and material information of the measured object is determined as the second emissivity; here, the visible light image containing the texture and material information of the measured object is mainly compared with the picture of common materials, and whether the texture and material information of the measured object in the visible light image is consistent with the known texture and material information in the picture of common materials is judged through the similarity information of the two, and then the material type of the measured object is determined, and the second emissivity corresponding to the material is obtained based on the correspondence between the known material and the emissivity.

[0100] Finally, the first emissivity is verified using the second emissivity, and the emissivity result is determined according to the verification result. Specifically, the second emissivity is compared with the above-mentioned first emissivity, and the deviation of the first emissivity is determined according to the difference value information, for example, a difference threshold value can be preset, and the obtained difference value information is compared with the difference threshold value to determine whether the first emissivity has a large deviation, and then the first emissivity can be verified.

[0101] If the first emissivity deviation is small, the first emissivity can be used as the emissivity result; if the first emissivity deviation is too large, the second emissivity can be used as the emissivity result if necessary, to further correct the first emissivity, thereby further improving the accuracy of the emissivity result.

[0102] At the same time, the visible light image photographed in the process of obtaining the second emissivity can also be synchronously displayed with the thermal radiation image on the user interface, so that the display result of the user interface is more clear and intuitive.

[0103] Of course, the point cloud data acquisition link can also not be set, and the above-mentioned second emissivity can be directly used as the emissivity result of the measured object, and the obtained thermal imaging intensity data can be combined to construct the temperature field information.

[0104] The implementation process of the above method will be described in detail through two specific application scenarios.

[0105] Referring to the accompanying drawings Figure 6 In this embodiment, the laser point cloud data of the measured object is obtained by a point cloud sensor, and the thermal imaging intensity data of the measured object is obtained by a thermal imaging sensor.

[0106] When using the point cloud sensor and the thermal imaging sensor, the two visual angles are as much as possible to overlap, and the correspondence of the pixels of the two is obtained through calibration. In actual application, the laser radar which is currently commonly used can be used as the point cloud sensor. At a certain moment, the laser radar emits a laser beam to a certain point on the measured object, and obtains the measurement signal returned by the object.

[0107] Through the measurement signal, the direction information and distance information of the certain point on the measured object can be obtained, and the intensity of the reflected light of the measured object can be obtained, and then the reflectivity of the surface of the object can be obtained. For the opaque object, the reflectivity and the emissivity are almost normalized, so the reflectivity can be used to preliminarily evaluate the emissivity of the measured object.

[0108] After scanning a plurality of points, the point cloud data of the measured region can be formed. According to the point cloud data of the measured region, the surface profile of the measured object can be obtained, so that the normal direction of the measured object can be obtained, and then the included angle between the normal direction of the object and the shooting direction, i.e. the surface angle, can be obtained.

[0109] After obtaining the surface angle information of the object, the emissivity obtained through the reflection intensity can be partially corrected. For example, for the measured object whose surface is perpendicular to the sensor, the reflectivity can be directly used, i.e. the preliminary emissivity can be directly used as the emissivity result.

[0110] For the measured object with a certain angle, the reflection intensity obtained by the point cloud sensor can be underestimated, so the preliminary emissivity needs to be corrected according to the surface angle of the measured object. According to the pre-established emissivity curve of different directions of the surface, i.e. the relationship curve between the surface angle and the emissivity, the actual emissivity value corresponding to the surface angle can be obtained. The actual emissivity value is used as the first emissivity, and the first emissivity is used as the emissivity result of the measured object, so as to realize the correction of the preliminary emissivity. Finally, the emissivity result (i.e. the emissivity of the surface of the object) is used to calculate the accurate temperature data of the corresponding point cloud of the measured object in combination with the radiation intensity data obtained by the thermal imaging sensor, so that the temperature field information of the measured object can be obtained.

[0111] More preferably, referring to the accompanying drawings Figure 7Further, a visible light sensor can be further added, and a visible light image of the measured region containing the measured object is synchronously acquired through the visible light sensor, which can further provide two parts of information, one is the color of the measured region, which assists in segmenting the point cloud and determining the range of the measured region, and then distinguishing the background region and the measured object in the measured region; the other is to provide the texture and material information of the measured object, and by comparing the visible light image with the picture of common materials, the material type to which the measured object belongs is determined, which can assist in analyzing the material, according to the material of the measured object, the corresponding second emissivity of the material of the measured object can be determined by using the corresponding relationship between the known material and the emissivity, so as to further improve the accuracy of the emissivity result obtained based on the point cloud sensor, and the accurate temperature data of the measured region can be obtained by combining the radiation intensity data obtained by the thermal imaging sensor, so as to obtain the temperature field information of the measured object.

[0112] Therefore, through the comprehensive application of the above different types of sensors, multiple information of the measured region can be acquired, the distance, direction and reflectivity information of the measured object can be obtained, which can be used for emissivity calculation of the measured object, and more accurate temperature measurement can be realized by combining the radiation intensity data obtained by the thermal imaging sensor, and the temperature measurement method is suitable for large-scale temperature measurement, and the obtained temperature data is more accurate and reliable.

[0113] The point cloud correction-based temperature field information acquisition device provided by the present application is described below, and the point cloud correction-based temperature field information acquisition device described below can be correspondingly referred to the point cloud correction-based temperature field information acquisition method described above.

[0114] Figure 8 The point cloud correction-based temperature field information acquisition device provided by the present application is described below, and the point cloud correction-based temperature field information acquisition device described below can be correspondingly referred to the point cloud correction-based temperature field information acquisition method described above.

[0115] The first acquisition module 810 is configured to acquire laser point cloud data of the measured object collected by the laser sensor, wherein the laser point cloud data includes direction information, distance information and reflected light intensity information of each point on the surface of the measured object.

[0116] The first processing module 820 is configured to obtain the preliminary emissivity of each point on the surface of the measured object according to the reflected light intensity information of each point on the surface of the measured object.

[0117] The second processing module 830 is configured to determine the surface angle of the measured object according to the direction information and the distance information of each point on the surface of the measured object, wherein the surface angle is the included angle between the normal direction of the measured object and the preset shooting direction of the point cloud sensor.

[0118] The third processing module 840 is configured to correct the preliminary emissivity of each point on the surface of the measured object according to the surface angle of the measured object, to obtain the emissivity result of each point on the surface of the measured object.

[0119] The second acquisition module 850 is configured to acquire the radiation intensity data of each point on the surface of the measured object.

[0120] The fourth processing module 860 is configured to calculate the temperature field information of the measured object according to the emissivity result of each point on the surface of the measured object, the radiation intensity data, and the distance information.

[0121] Specifically, the first acquisition module 810 includes:

[0122] The signal transceiver unit is configured to respectively emit laser signals to each point on the surface of the measured object, and receive measurement signals returned from each point on the surface of the measured object.

[0123] The information extraction unit is configured to, for each point on the surface of the measured object, acquire the direction information, the distance information, and the reflected light intensity information of each point on the surface of the measured object according to the measurement signal of the point.

[0124] Specifically, the first processing module 820 includes:

[0125] The reflectivity calculation unit is configured to calculate the reflectivity of each point on the surface of the measured object according to the reflected light intensity information of each point on the surface of the measured object.

[0126] The preliminary emissivity calculation unit is configured to determine whether the measured object is a non-transparent object, and calculate the preliminary emissivity of each point on the surface of the measured object according to a normalized correspondence relationship between the reflectivity and the emissivity of the non-transparent object after determining that the measured object is a non-transparent object.

[0127] Specifically, the second processing module 830 includes:

[0128] The contour information acquisition unit is configured to acquire the surface contour information of the measured object according to the direction information and the distance information of each point on the surface of the measured object.

[0129] The normal direction acquisition unit is configured to determine the normal direction of the measured object according to the surface contour information of the measured object.

[0130] The surface angle acquisition unit is configured to take an included angle between the normal direction of the measured object and a preset shooting direction of a point cloud sensor of the laser point cloud collection device as the surface angle of the measured object.

[0131] In one specific embodiment, the third processing module 840 includes:

[0132] The first discrimination module is configured to take the preliminary emissivity as the first emissivity when the surface angle of the measured object is within the preset angle threshold range.

[0133] The second discrimination module is configured to determine the emissivity corresponding to the surface angle of the current measured object from the pre-constructed relationship curve between the surface angle and the emissivity, and take the emissivity as the first emissivity when the surface angle of the measured object is outside the preset angle threshold range.

[0134] The first result determination module is configured to take the first emissivity as the emissivity result.

[0135] In another specific embodiment, the third processing module 840 includes:

[0136] The first discrimination unit is configured to take the preliminary emissivity as the first emissivity when the surface angle of the measured object is within the preset angle threshold range.

[0137] The second discrimination unit is configured to determine the emissivity corresponding to the surface angle of the current measured object from the pre-constructed relationship curve between the surface angle and the emissivity, and take the emissivity as the first emissivity when the surface angle of the measured object is outside the preset angle threshold range.

[0138] The image acquisition unit is configured to acquire a visible light image of the measured object.

[0139] The first processing unit is configured to determine the texture and material information of the measured object according to the visible light image.

[0140] The second processing unit is configured to determine the emissivity corresponding to the texture and material information of the current measured object according to the pre-set corresponding relationship between the texture and material information and the emissivity, and take the emissivity as the second emissivity.

[0141] The verification unit is configured to verify the first emissivity by the second emissivity, and determine the emissivity result according to the verification result.

[0142] In addition, the embodiment of the present application also provides a temperature field information acquisition system based on point cloud correction, which comprises a point cloud sensor, a thermal imaging sensor and a data processing device, and the point cloud sensor and the thermal imaging sensor are connected with the data processing device.

[0143] The point cloud sensor is configured to collect laser point cloud data of the measured object.

[0144] The thermal imaging sensor is configured to collect radiation intensity data of each point on the surface of the measured object.

[0145] The data processing device is configured to acquire laser point cloud data of a measured object collected by a point cloud sensor, wherein the laser point cloud data comprises direction information, distance information and reflected light intensity information of each point on the surface of the measured object; obtain a preliminary emissivity of each point on the surface of the measured object according to the reflected light intensity information of each point on the surface of the measured object; determine a surface angle of the measured object according to the direction information and the distance information of each point on the surface of the measured object, wherein the surface angle is an included angle between a normal direction of the measured object and a preset shooting direction of the point cloud sensor; correct the preliminary emissivity of each point on the surface of the measured object according to the surface angle of the measured object to obtain an emissivity result of each point on the surface of the measured object; acquire radiation intensity data of each point on the surface of the measured object; and calculate temperature field information of the measured object according to the emissivity result, the radiation intensity data and the distance information of each point on the surface of the measured object.

[0146] More preferably, the temperature field information acquisition system based on point cloud correction further comprises a visible light sensor configured to collect a visible light image of the measured object.

[0147] The data processing device is further configured to determine whether the surface angle of the measured object is within a preset angle threshold range, and if the surface angle of the measured object is within the preset angle threshold range, the preliminary emissivity is taken as a first emissivity; if the surface angle of the measured object is outside the preset angle threshold range, an emissivity corresponding to the surface angle of the current measured object is determined from a pre-constructed relationship curve between surface angle and emissivity, and taken as the first emissivity; a visible light image of the measured object is acquired; texture and material information of the measured object is determined according to the visible light image; an emissivity corresponding to the texture and material information of the current measured object is determined according to a preset corresponding relationship between texture and material information and emissivity, and taken as a second emissivity; the first emissivity is verified by using the second emissivity, and an emissivity result is determined according to a verification result.

[0148] Figure 9 An example of a schematic diagram of a physical structure of an electronic device is shown in FIG. 1. Figure 9As shown, the electronic device can include a processor 910, a communications interface 920, a memory 930, and a communications bus 940, wherein the processor 910, the communications interface 920, and the memory 930 complete mutual communication through the communications bus 940. The processor 910 can invoke the logical instructions in the memory 930 to execute the temperature field information acquisition method based on point cloud correction, which includes: acquiring laser point cloud data of a measured object collected by a point cloud sensor; wherein the laser point cloud data includes direction information, distance information, and reflected light intensity information of each point on the surface of the measured object; obtaining a preliminary emissivity of each point on the surface of the measured object according to the reflected light intensity information of each point on the surface of the measured object; determining a surface angle of the measured object according to the direction information and the distance information of each point on the surface of the measured object; wherein the surface angle is an included angle between a normal direction of the measured object and a preset shooting direction of the point cloud sensor; correcting the preliminary emissivity of each point on the surface of the measured object according to the surface angle of the measured object to obtain an emissivity result of each point on the surface of the measured object; acquiring radiation intensity data of each point on the surface of the measured object; and calculating the temperature field information of the measured object according to the emissivity result, the radiation intensity data, and the distance information of each point on the surface of the measured object.

[0149] In addition, the logical instructions in the memory 930 described above can be implemented in the form of a software function unit and sold or used as an independent product, which can be stored in a computer-readable storage medium. Based on such understanding, the technical solutions of the present application essentially or the part that contributes to the prior art or part of the technical solutions can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including a plurality of instructions to make a computer device (which can be a personal computer, a server, or a network device, etc.) execute all or part of the steps of the methods described in various embodiments of the present application. The aforementioned storage medium includes: a U disk, a mobile hard disk, a read-only memory (ROM, Read-Only Memory), a random access memory (RAM, Random Access Memory), a magnetic disk or an optical disk, and various media that can store program codes.

[0150] In another aspect, the present application also provides a computer program product, which comprises a computer program stored in a non-transitory computer readable storage medium, and the computer program can be executed by a processor to enable a computer to perform the temperature field information acquisition method based on point cloud correction provided by the above method, and the method comprises: acquiring laser point cloud data of a measured object collected by a point cloud sensor; wherein the laser point cloud data comprises direction information, distance information and reflected light intensity information of each point on the surface of the measured object; obtaining a preliminary emissivity of each point on the surface of the measured object according to the reflected light intensity information of each point on the surface of the measured object; determining a surface angle of the measured object according to the direction information and the distance information of each point on the surface of the measured object; wherein the surface angle is an included angle between a normal direction of the measured object and a preset shooting direction of the point cloud sensor; correcting the preliminary emissivity of each point on the surface of the measured object according to the surface angle of the measured object to obtain an emissivity result of each point on the surface of the measured object; acquiring radiation intensity data of each point on the surface of the measured object; and calculating the temperature field information of the measured object according to the emissivity result, the radiation intensity data and the distance information of each point on the surface of the measured object.

[0151] In another aspect, the present application also provides a non-transitory computer readable storage medium, which stores a computer program, and the computer program is executed by a processor to implement the temperature field information acquisition method based on point cloud correction provided by the above method, and the method comprises: acquiring laser point cloud data of a measured object collected by a point cloud sensor; wherein the laser point cloud data comprises direction information, distance information and reflected light intensity information of each point on the surface of the measured object; obtaining a preliminary emissivity of each point on the surface of the measured object according to the reflected light intensity information of each point on the surface of the measured object; determining a surface angle of the measured object according to the direction information and the distance information of each point on the surface of the measured object; wherein the surface angle is an included angle between a normal direction of the measured object and a preset shooting direction of the point cloud sensor; correcting the preliminary emissivity of each point on the surface of the measured object according to the surface angle of the measured object to obtain an emissivity result of each point on the surface of the measured object; acquiring radiation intensity data of each point on the surface of the measured object; and calculating the temperature field information of the measured object according to the emissivity result, the radiation intensity data and the distance information of each point on the surface of the measured object.

[0152] The device embodiments described above are only schematic, wherein the units shown as separate components can or can not be physically separate, and the components shown as units can or can not be physical units, i.e., can be located in one place or distributed on a plurality of network units. Part or all of the modules can be selected according to actual needs to achieve the purpose of the present embodiment scheme. Those skilled in the art can understand and implement without creative labor.

[0153] Those skilled in the art can clearly understand the implementation of the embodiments by the description of the above embodiments, and the embodiments can be implemented by means of software and necessary universal hardware platforms, and of course, can also be implemented by hardware. Based on such understanding, the above technical solutions can be embodied in the form of a software product, and the computer software product can be stored in a computer readable storage medium, such as a ROM / RAM, a magnetic disk, an optical disk, etc., and includes a plurality of instructions to make a computer device (which can be a personal computer, a server, or a network device, etc.) execute the method described in each embodiment or some parts of the embodiment.

[0154] Finally, it should be noted that: the above examples are only used to illustrate the technical solutions of the present application, and not to limit them; although the present application has been described in detail with reference to the foregoing examples, those skilled in the art should understand that: it can still modify the technical solutions recorded in the foregoing examples, or make equivalent replacement for some technical features thereof; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A method for acquiring temperature field information based on point cloud correction, characterized in that, The method comprises the following steps: acquiring laser point cloud data of a measured object collected by a point cloud sensor; wherein the laser point cloud data comprises direction information, distance information and reflected light intensity information of each point on the surface of the measured object; obtaining a preliminary emissivity of each point on the surface of the measured object according to the reflected light intensity information of each point on the surface of the measured object; determining a surface angle of the measured object according to the direction information and the distance information of each point on the surface of the measured object; wherein the surface angle is an included angle between a normal direction of the measured object and a preset shooting direction of the point cloud sensor; correcting the preliminary emissivity of each point on the surface of the measured object according to the surface angle of the measured object to obtain an emissivity result of each point on the surface of the measured object; acquiring radiation intensity data of each point on the surface of the measured object; calculating a temperature field information of the measured object according to the emissivity result, the radiation intensity data and the distance information of each point on the surface of the measured object; wherein the temperature field information of the measured object comprises temperature information of each point on the measured object.

2. The temperature field information acquisition method based on point cloud correction according to claim 1, characterized in that, The method for acquiring laser point cloud data of a measured object comprises the following steps: emitting laser signals to each point on the surface of the measured object respectively and receiving measurement signals returned from each point on the surface of the measured object; for each point on the surface of the measured object, acquiring direction information, distance information and reflected light intensity information of the point according to the measurement signal of the point.

3. The temperature field information acquisition method based on point cloud correction according to claim 1, characterized in that, The method for obtaining a preliminary emissivity of each point on the surface of the measured object according to the reflected light intensity information of each point on the surface of the measured object comprises the following steps: calculating a reflectivity of each point on the surface of the measured object according to the reflected light intensity information of each point on the surface of the measured object; determining whether the measured object is a non-transparent object; and calculating the preliminary emissivity of each point on the surface of the measured object according to a corresponding relationship between the reflectivity and the emissivity of the non-transparent object after determining that the measured object is a non-transparent object.

4. The temperature field information acquisition method based on point cloud correction according to claim 1, characterized in that, The method for determining a surface angle of the measured object according to the direction information and the distance information of each point on the surface of the measured object comprises the following steps: acquiring surface profile information of the measured object according to the direction information and the distance information of each point on the surface of the measured object; determining a normal direction of the measured object according to the surface profile information of the measured object; taking an included angle between the normal direction of the measured object and a preset shooting direction of the point cloud sensor as the surface angle of the measured object.

5. The temperature field information acquisition method based on point cloud correction according to claim 1, characterized in that, The method for correcting the preliminary emissivity of each point on the surface of the measured object according to the surface angle of the measured object comprises the following steps: if the surface angle of the measured object is within a preset angle threshold range, taking the preliminary emissivity as a first emissivity; if the surface angle of the measured object is outside the preset angle threshold range, determining an emissivity corresponding to the surface angle of the current measured object from a relationship curve between surface angles and emissivities constructed in advance to serve as the first emissivity; taking the first emissivity as the emissivity result.

6. The temperature field information acquisition method based on point cloud correction according to claim 1, characterized in that, The method for correcting the preliminary emissivity of each point on the surface of the measured object according to the surface angle of the measured object comprises the following steps: If the surface angle of the measured object is within a preset angle threshold range, the preliminary emissivity is taken as the first emissivity; If the surface angle of the measured object is outside the preset angle threshold range, an emissivity corresponding to the surface angle of the current measured object is determined from a pre-constructed surface angle-emissivity relationship curve, and taken as the first emissivity; An optical image of the measured object is acquired; Texture and material information of the measured object is determined according to the optical image; An emissivity corresponding to the texture and material information of the current measured object is determined according to a preset texture and material information-emissivity correspondence, and taken as a second emissivity; The first emissivity is verified by using the second emissivity, and an emissivity result is determined according to a verification result.

7. A temperature field information acquisition device based on point cloud correction, characterized by, Comprise: A first acquisition module is configured to acquire laser point cloud data of a measured object collected by a point cloud sensor, wherein the laser point cloud data comprises direction information, distance information and reflected light intensity information of each point on the surface of the measured object; A first processing module is configured to obtain a preliminary emissivity of each point on the surface of the measured object according to the reflected light intensity information of each point on the surface of the measured object; A second processing module is configured to determine a surface angle of the measured object according to the direction information and the distance information of each point on the surface of the measured object, wherein the surface angle is an included angle between a normal direction of the measured object and a preset shooting direction of the point cloud sensor; A third processing module is configured to correct the preliminary emissivity of each point on the surface of the measured object according to the surface angle of the measured object, and obtain an emissivity result of each point on the surface of the measured object; A second acquisition module is configured to acquire radiation intensity data of each point on the surface of the measured object; A fourth processing module is configured to calculate temperature field information of the measured object according to the emissivity result, the radiation intensity data and the distance information of each point on the surface of the measured object, wherein the temperature field information of the measured object comprises temperature information of each point on the measured object.

8. A temperature field information acquisition system based on point cloud correction, characterized by, Comprise a point cloud sensor, a thermal imaging sensor and a data processing device, wherein the point cloud sensor and the thermal imaging sensor are connected to the data processing device; The point cloud sensor is configured to collect laser point cloud data of a measured object; The thermal imaging sensor is configured to collect radiation intensity data of each point on the surface of the measured object; The data processing device is configured to acquire laser point cloud data of a measured object collected by a point cloud sensor, wherein the laser point cloud data comprises direction information, distance information and reflected light intensity information of each point on the surface of the measured object; obtain a preliminary emissivity of each point on the surface of the measured object according to the reflected light intensity information of each point on the surface of the measured object; determine a surface angle of the measured object according to the direction information and the distance information of each point on the surface of the measured object, wherein the surface angle is an included angle between a normal direction of the measured object and a preset shooting direction of the point cloud sensor; correct the preliminary emissivity of each point on the surface of the measured object according to the surface angle of the measured object to obtain an emissivity result of each point on the surface of the measured object; acquire radiation intensity data of each point on the surface of the measured object; and calculate temperature field information of the measured object according to the emissivity result, the radiation intensity data and the distance information of each point on the surface of the measured object.

9. The temperature field information acquisition system based on point cloud correction according to claim 8, characterized in that, The data processing device further comprises a visible light sensor configured to acquire a visible light image of the measured object. The data processing device is further configured to determine whether the surface angle of the measured object is within a preset angle threshold range, and if the surface angle of the measured object is within the preset angle threshold range, the preliminary emissivity is taken as a first emissivity. If the surface angle of the measured object is outside the preset angle threshold range, an emissivity corresponding to the surface angle of the current measured object is determined from a pre-constructed relationship curve between surface angles and emissivities, and taken as the first emissivity; a visible light image of the measured object is acquired; texture and material information of the measured object is determined according to the visible light image; an emissivity corresponding to the texture and material information of the current measured object is determined according to a preset corresponding relationship between texture and material information and emissivities, and taken as a second emissivity; the first emissivity is verified by using the second emissivity, and an emissivity result is determined according to a verification result.

10. An electronic device comprising a memory, a processor, and a computer program stored on the memory and executable on the processor, characterized in that, The processor executes the program to implement the steps of the temperature field information acquisition method based on point cloud correction according to any one of claims 1 to 6.

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