Scanning device

Abstract

Scanning device (100) for spatial surveying of an environment (200), comprising a LiDAR sensor unit (10) with a light source for emitting transmitting light (20) into the environment (200), a receiving unit (12) for receiving transmitted light (20) remitted and / or reflected in the environment (200) as received light (22), and an evaluation unit (14), wherein the evaluation unit (14) is configured for evaluating the LiDAR data (70) acquired by the receiving unit (12) for spatial surveying of the environment (200), characterized in that the LiDAR sensor unit (10) comprises an optical sensor arrangement (30) rotatably mounted about a rotational axis (48) with two sensor sections (40, 44), wherein the sensor sections (40, 44) are spaced apart from each other and arranged at different positions with respect to the rotational axis (48). are,wherein a first of the sensor sections (40) is formed by optically sensitive elements of the receiving unit (12) and determines the LiDAR data (70), wherein furthermore a second of the sensor sections (44) determines optical environmental data (72), and wherein the evaluation unit (14) is configured for evaluating the environmental data (72), and further configured, based on the LiDAR data (70) and the environmental data (72), for determining stereo 3D data (74) to improve the spatial surveying of the environment (200).

Description

The invention relates to a scanning device for spatial measurement of an environment, comprising a LiDAR sensor unit with a light source for emitting transmitted light into the environment, a receiving unit for receiving transmitted light remitted and / or reflected in the environment as received light, and an evaluation unit, wherein the evaluation unit is configured to evaluate the LiDAR data determined by the receiving unit for spatial measurement of the environment. Monitoring an environment, for example for obstacle detection by autonomous vehicles, usually relies on a spatial survey of at least a section of the environment. LiDAR (Light Detection and Ranging) sensor units are often used as scanning devices for this purpose. Objects in the environment, especially obstacles, are detected by means of an emitted light signal, usually laser light, and the corresponding reception of remitted and / or reflected portions of this light signal in the surrounding area. Distances to the individual points of remission or reflection in the environment are then determined by evaluating the received light signals, particularly their travel times. The transmitted light, especially if it is laser light, is usually a light beam with a small cross-sectional area. However, in the near range, which extends, for example, to a distance of up to 2 meters from the scanning device, the problem arises that the travel time of the light signals is on the order of the pulse widths used in the transmitted light signals, thus making precise distance measurement difficult. Based on the known scanning devices described above, it is therefore an object of the present invention to improve scanning devices of the prior art. In particular, it is an object of the present invention to provide a scanning device that enables improved measurement of a close-range environment. The problem is solved according to the invention by a scanning device according to independent claim 1. Further developments of the scanning device according to the invention are described in the dependent claims, the description and the drawings. According to the invention, the problem is solved by a scanning device for a spatial measurement of an environment, comprising a LiDAR sensor unit with a light source for emitting transmitted light into the environment, a receiving unit for receiving transmitted light remitted and / or reflected in the environment as received light, and an evaluation unit, wherein the evaluation unit is designed to evaluate the data determined by the receiving unit for the spatial measurement of the environment.The scanning device according to the invention is characterized in that the LiDAR sensor unit has an optical sensor arrangement rotatably mounted about an axis of rotation, with two sensor sections, wherein the sensor sections are spaced apart from each other and arranged at different positions with respect to the axis of rotation, wherein a first of the sensor sections is formed by optically sensitive elements of the receiving unit and determines the LiDAR data, wherein furthermore a second of the sensor sections (44) determines optical environmental data, and wherein the evaluation unit is designed for evaluating the environmental data, and furthermore is designed based on the LiDAR data and the environmental data for determining stereo 3D data to improve the spatial measurement of the environment. The invention is based on the understanding that by capturing the environment using the two sensor sections, it is possible to capture the environment from two different perspectives, from which distance and depth information can be obtained using stereoscopic methods. The distance and depth information obtained by stereoscopy can then be used to improve, for example, correct, validate, and / or replace the distance and depth information of the LiDAR sensor unit. The distance and depth information obtained by stereoscopy is referred to herein as stereo 3D data, wherein the LiDAR data acquired by the receiving unit or the first sensor section and the environmental data acquired by the second sensor section are preferably incorporated, at least partially, into the stereo 3D data. The scanning device according to the invention preferably comprises the usual components of a LiDAR sensor unit. A light source, in particular a laser source, provides transmitted light, especially in the form of a laser beam, which is emitted into the environment to be measured. This is preferably done by scanning the environment to be measured with the transmitted light, for example by rotating the entire light source or elements of the light source, such as a deflecting mirror. Since the rotational position of the light source is known for any given time, the transmitted light can be emitted continuously and / or discretely into the environment with a known angular correlation. The rotation can be continuous with the same direction of rotation, or oscillatory with a constantly changing direction of rotation. The emitted light encounters objects in the surrounding area that may be located at varying distances from the scanning device according to the invention. The light is remitted or reflected by these objects. This remission and / or reflection of the transmitted light can occur at least partially in the direction of the scanning device according to the invention, and can then be registered therein by the receiving unit as received light. The information determined by the receiving unit, for example, the transit time of the received light, is referred to as LiDAR data within the meaning of the invention and is evaluated by the evaluation unit. Since, as described above, the transmitted light is emitted into the environment with a known angular correlation, the received light can also exhibit a correspondingly known angular correlation with respect to the environment. This can be taken into account during evaluation by the evaluation unit, and a measurement of the environment, and in particular a determination of the distances of objects in the environment to the scanning device, can thereby be carried out. The scanning device according to the invention is characterized in that the evaluation performed by the evaluation unit for measuring the environment is improved by incorporating further information. To provide this information, the LiDAR sensor unit of the scanning device according to the invention has an optical sensor arrangement rotatably mounted about a rotational axis, comprising two sensor sections. A sensor section within the meaning of the invention is, in particular, a component that is optically sensitive and thus designed to detect optical information, for example, a CMOS sensor or a CCD sensor, but also even a simple (avalanche) photodiode, a photomultiplier, or a photoresistor. Furthermore, the first of the two sensor sections is formed by optically sensitive elements of the receiver unit. In other words, the first sensor section is part of the LiDAR sensor unit already described above, which is used for basic environmental mapping. In particular, the first sensor section determines the LiDAR data on which the measurement of the environment made possible by the LiDAR sensor unit is based. In addition to the first sensor section, the sensor arrangement of the scanning device according to the invention has a further, second sensor section. This section is also designed to determine information based on optical signals from the environment, referred to as environmental data in the context of the invention. The two sensor sections can be constructed identically or differently in their technical implementation. In particular, it is preferable that the two sensor sections can be read out separately. Furthermore, the two sensor sections can be read out simultaneously or with a time delay. The two sensor sections are arranged within the sensor assembly such that they are spaced apart from each other. In particular, the two sensor sections, also due to their spaced-apart arrangement as described above, are positioned at different locations, especially at different distances, with respect to the axis of rotation of the sensor assembly. In other words, this spacing between the sensors and their different positions relative to the axis of rotation ensures that the two sensor sections observe different areas in the environment, particularly different angular ranges, and are sensitive to optical signals from different parts of the environment. This results in the LiDAR data and the environmental data, each acquired by one of the two sensor sections, being distinct. In particular, each of the two sensor sections has its own detection range. In other words, the detection ranges differ and are not congruent. Preferably, the respective detection range can extend along a viewing direction or sensor axis of the corresponding sensor section, i.e., be arranged and aligned along this viewing direction. As already explained, the sensor arrangement is rotatably mounted about an axis of rotation in the LiDAR sensor unit and / or the entire scanning device according to the invention. During operation of the scanning device according to the invention, the two sensor sections also rotate about the axis of rotation. This ensures that the two detection areas of the sensor sections also rotate and thus cover different areas of the environment during the rotation. Preferably, the rotation of the sensor arrangement can be adapted to the scanning process of the light source described above, and in particular, synchronized. Since, as described above, the first sensor section is part of the LiDAR sensor unit, this ensures that the first sensor section can fulfill its function as an optically sensitive element of the receiving unit. Preferably, the first sensor section is positioned in the sensor arrangement, and its rotation is adapted to the scanning process of the light source, such that the angular range of the surroundings illuminated by the light source can be observed at least partially, and in particular completely, by the first sensor section. Simultaneously, by rotating the sensor array, it can be achieved that the same area in the environment can be measured by each of the two sensor sections: by the first sensor section at a first rotation angle and by the second sensor section at a second rotation angle. In other words, an area in the environment that is measured by the first sensor section at a first point in time during the rotation, or at a first rotational position of the sensor array, can be measured by the second sensor section at a second point in time during the rotation, or at a second rotational position of the sensor array, if the sensor array has rotated further accordingly. In this way, it can be achieved that both LiDAR data acquired by the first sensor section and environmental data acquired by the second sensor section are available for the area of ​​the environment to be measured. Since the two sensor sections, as described above, have different and, in particular, differently oriented reception areas, and are sensitive to different rotation angles of the sensor array for a given section of the area to be measured, the corresponding LiDAR and environmental data are acquired from different perspectives for each section of the area to be measured. LiDAR and environmental data originating from the same object in the environment will differ, for example, due to at least a slightly different viewing angle of the respective object from the two sensor sections.In this way, methods of stereographic projection can be applied in the evaluation carried out by the evaluation unit to determine stereo 3D data. Depending on the distance of an object in the environment, the LiDAR and environmental data corresponding to that object, as determined by the two sensor sections, are offset. From this offset and the known properties of the scanning device according to the invention, in particular the position and orientation of the sensor sections and their respective reception areas, stereo 3D data can be generated, which, for example, indicate and / or include the distance of the respective object from the scanning device according to the invention. In particular, the evaluation unit is designed to improve the spatial measurement of the environment, which is only possible with the conventional elements of the LiDAR sensor unit, by means of this additional information provided by the stereo 3D data. The stereo 3D data acquired in this way can include, in particular, distances between objects or independently identifiable sections of objects, such as corners, edges, or the like. These stereo distances derived from the stereo 3D data are also available in addition to the LiDAR distances determined solely by the LiDAR sensor unit. An improvement in environmental mapping can thus be achieved, in particular, by determining, for objects or sections of objects for which values ​​from both distance measurements are available, an actual distance output as a measurement result based on both raw distance values ​​obtained—that is, the respective values ​​of the LiDAR distance and the stereo distance. To improve the measurement, a weighted average can be calculated from the corresponding LiDAR and stereo distances. The LiDAR distances can then be corrected using the appropriate stereo distances. A plausibility check can also be performed during the calculation process, for example, to verify that a determined LiDAR distance agrees with the corresponding stereo distance within a defined margin of error. Improving spatial surveying can also include replacing determined LiDAR distance values ​​with correspondingly determined stereo distance values. The improvement can be applied to individual distance values, to distance values ​​for an entire object, or to all distance values. The evaluation unit can also be configured to perform the enhancement, in particular only if the signal strength (of the received light) and / or the signal-to-noise ratio (SNR) (of the received light) in the receiving unit of the LiDAR sensor unit falls below a predetermined threshold. Alternatively or additionally, the evaluation unit can also be configured to perform the enhancement, in particular only if the signal strength (of the received light) in the receiving unit of the LiDAR sensor unit exceeds a predetermined threshold. In particular, exceeding a certain signal strength and falling below a certain SNR indicate that the LiDAR sensor unit is performing a close-range measurement, which can be significantly improved by the stereo 3D data. Alternatively or additionally, the evaluation unit can also be configured to perform the improvement, specifically only when a LiDAR distance determined by the LiDAR sensor unit and / or a stereo distance contained in the stereo 3D data falls below a predetermined distance threshold. The distance threshold can be, for example, 5m, 3m, 2m, or 1m. This also allows the system to detect when a measurement is being taken at close range, at which point the improvement is initiated. The offset described above between the LiDAR data and the environmental data acquired by the two sensor sections is particularly greater the closer the detected object is to the scanning device according to the invention. Accordingly, the stereo 3D data acquired by the evaluation unit are more accurate and informative for objects close to the scanning device, i.e., in the so-called near field, than for objects further away. However, as explained above, spatial measurement using LiDAR alone is less accurate precisely in the near field. In other words, the additional acquisition and consideration of stereo 3D data enables, in the scanning device according to the invention, a near-field correction, i.e., an improvement in the spatial measurement in an area close to the scanning device, for example, within a distance range of 0 m to 1-2 m from the scanning device. The scanning device according to the invention, comprising a sensor arrangement with two sensor sections, has been described above. However, the scanning device according to the invention is not limited to this number of sensor sections. The corresponding sensor arrangement can also have three or more sensor sections, provided that at least one pair of these three or more sensor sections exhibits the properties of the first and second sensor sections described above. Furthermore, the scanning device according to the invention can be characterized in that the respective viewing directions of the two sensor sections, along which the respective sensor section is sensitive, enclose an angle Δα, preferably an angle Δα between 15° and 45°. This ensures that the reception areas of the two sensor sections, which, as described above, can extend along the viewing direction, are sufficiently different. An angle Δα between these viewing directions makes it particularly easy to ensure that the two reception areas are distinct. An angle Δα between 15° and 45° has proven to be a particularly good compromise, both to provide sufficiently distinct reception areas and to avoid requiring excessively large rotation angles of the sensor arrangement to capture the same area in the environment to be measured with both sensor sections. Since the viewing directions enclose an angle Δα, the two viewing directions intersect. It is preferred that the two viewing directions are arranged together in a common viewing plane. Alternatively or additionally, it is preferred that the two viewing directions intersect in front of the sensor sections, i.e., in the direction of the environment to be measured. This allows, for example, a particularly compact design of the scanning device. According to a further development of the scanning device according to the invention, it can also be provided that the viewing direction of at least one of the sensor sections is oriented transversely to the axis of rotation; preferably, the viewing directions of both sensor sections are oriented transversely to the axis of rotation. By orienting the viewing direction of one or both sensor sections transversely to the axis of rotation, a particularly unambiguous and simple geometric determination of the reception area of ​​the corresponding sensor section in the environment to be measured can be achieved. This facilitates the reconstruction of this reception area during the evaluation of the measurement data acquired by the respective sensor section by the evaluation unit. The scanning device according to the invention can also be further developed in that, during the rotation of the sensor arrangement, the two viewing directions each sweep over a sensor area, with the two sensor areas overlapping to form a scan area of ​​the scanning device of 60°, in particular 180°, preferably 360°. Each of the two sensor sections sweeps over a sensor area in the environment with its viewing direction, and data, i.e., LiDAR data or environmental data, can be determined within this sensor area by the respective sensor section. The scan area, as the area of ​​overlap of the two sensor areas, thus represents that part of the environment for which both LiDAR data and environmental data are available. For this scan area, the survey of the environment based on the LiDAR data obtained by the first sensor section can thus be improved by the stereo 3D data obtained using the additional environmental data from the second sensor section. A 60° scan range is particularly useful for improving the measurement of the area in front of the scanner, for example, to detect objects in the direction of travel of a vehicle. Larger scan ranges, such as 180°, provide a better overview of the surroundings, while a 360° scan range offers a 360° view. Furthermore, the scanning device according to the invention can be configured such that, during the rotation of the sensor arrangement, the two sensor sections each acquire a plurality of individual images as LiDAR data and environmental data, wherein the evaluation unit is configured to generate a first input image from the individual images of the first sensor section and to generate a second input image from the individual images of the second sensor section, and wherein the evaluation unit is configured to generate an output image from the first input image and the second input image. In other words, during the rotation of the sensor arrangement, data is acquired for different angular positions, in particular, an individual image is acquired for each of these angular positions.Preferably, the respective reception areas of the sensor sections and an angle increment between the individual angular positions can be coordinated in such a way that the areas of the environment that are photographed in the individual images do not overlap. By combining the individual images, which is generated by the evaluation unit, an input image of the entire sensor area of ​​the respective sensor section is obtained. This input image can be provided by the individual images, in particular without having to generate an image of the entire sensor area for every rotational position of the sensor arrangement. In particular, the input image of the first sensor section can represent or include LiDAR data, especially the determined LiDAR distances. Depending on the design of the second sensor section, the input image of the second sensor section can, for example, include a one- or two-dimensional image of the environment. Subsequently, the evaluation unit generates an output image from the two input images of the two sensor sections. For this purpose, the information from these two input images is used to generate the output image within the rotation angle range in which both input images are present. The output image can thus preferably be generated for the scan range of the scanning device according to the invention as described above. There are several ways to generate the output image. For example, an existing representation of the environment from the input image of the second sensor section can be supplemented by additionally displaying LiDAR distances based on the LiDAR data from the first sensor section. Furthermore, a display of stereo distances, determined as described above by an evaluation based on both the LiDAR data from the first sensor section and the environmental data from the second sensor section, is also conceivable as the output image in the input image of the second sensor section. In particular, the output image can also include the previously described improvement in environmental measurement, where distances to objects in the environment are improved by combining LiDAR distances and stereo distances. The examples described above do not constitute a complete description of the possible variations of the initial image. Both the input and output images can be in a purely computer-readable format. Additionally, a human-readable display of the input and / or output images can also be generated, for example, for display on a monitor or smart glasses. The scanning device according to the invention can be further developed such that the output image includes the improved survey of the environment resulting from the acquired stereo 3D data, preferably corresponding to the improved survey of the environment resulting from the acquired stereo 3D data. According to this further development, the output image thus contains the improved spatial survey by taking both sensor sections into account; preferably, it contains only this survey. Again, the output image can preferably be generated for the scan area of ​​the scanning device according to the invention described above. In other words, the output images obtained as a result of operating the scanning device according to the invention depict a spatial survey of the environment improved by stereo 3D data. Furthermore, the scanning device according to the invention can be further developed such that it has an output interface that communicates with the evaluation unit for outputting the first input image and / or the second input image and / or the output image. Such an output interface enables the input images or the output image to be forwarded and / or reproduced. An output interface within the meaning of the invention can already be a connector for a correspondingly provided data line. Preferably, however, an output interface can also include an actual optical representation of the respective image, for example, by designing the output interface as a display or smart glasses. Furthermore, the scanning device according to the invention can be characterized in that an optically sensitive area of ​​each of the two sensor sections corresponds to a single image point. Such an image point can also be referred to as a pixel. Preferably, a limited area of ​​the environment is observed by the corresponding sensor section, in particular an area directly around the viewing direction of the sensor section. In the embodiment described above, in which a multitude of individual images are captured during the rotation of the sensor arrangement, a line image of the environment results for both the input images of the two sensor sections and for the output image. Alternatively, in the scanning device according to the invention, an optically sensitive area of ​​each of the two sensor sections can correspond to a column of pixels, wherein the pixels in the column are arranged along a longitudinal extent, and wherein the longitudinal extent of the respective column is preferably aligned parallel to the axis of rotation of the sensor arrangement. In the embodiment described above, in which a plurality of individual images are captured during the rotation of the sensor arrangement, a two-dimensional image of the surroundings is obtained for both the input images of the two sensor sections and for the output image. Furthermore, the scanning device according to the invention can also be configured such that the second sensor section is designed as a component of one of the following sensor units: - component of a LiDAR sensor unit - component of a background light measurement unit This list is not exhaustive, and other sensor units are also conceivable as a basis for the second sensor section. The LiDAR sensor unit, of which the second sensor section is a component, can be the same LiDAR sensor unit that already includes the first sensor section, or it can be a completely independent LiDAR sensor unit. In this embodiment of the scanning device according to the invention, the environmental data of the second sensor section are therefore also available as LiDAR data. Thus, using LiDAR data from both sensor sections, distances to objects in the environment can be determined, which together then enable an improvement in the measurement of the environment, for example, through the methods of averaging or plausibility checks already described above. A background light measuring unit, in turn, can, for example, comprise a camera chip of an electronic camera. In this embodiment of the scanning device according to the invention, LiDAR distances to objects in the environment can be determined via the first sensor section as part of the LiDAR sensor unit. The second sensor section enables the acquisition of the environment as a 2D image, whereby, due to the different viewing angles of the two sensor sections, as already explained above, stereo distances can be determined by stereography. In this embodiment as well, an overall improvement in the measurement of the environment is made possible, for example, by the methods of averaging or plausibility check already described above. The scanning device according to the invention can also be characterized in that the sensor sections are arranged vertically spaced apart parallel to the axis of rotation of the sensor arrangement. In other words, if the two sensor sections measure the same area in the environment, the height difference resulting from the vertical spacing of the two sensor sections parallel to the axis of rotation creates an additional difference in the viewing angle from which each sensor section measures the environment. This additional difference in viewing angle can be taken into account during evaluation by the evaluation unit in order to further improve the spatial measurement of the environment. Furthermore, the scanning device according to the invention can be configured such that the sensor arrangement has an optical sensor element, wherein the sensor sections are configured as geometrically spaced sections of the sensor element, or that the sensor arrangement has two geometrically separate optical sensor elements, wherein each sensor element comprises one of the sensor sections. In this embodiment of the scanning device according to the invention, it is possible, on the one hand, to use only a single optical sensor element to provide both sensor sections. In this way, for example, a dual readout electronics can be dispensed with. This can be particularly advantageous for embodiments in which the two sensor sections are technically identical or designed in the same way. Alternatively, a separate sensor element can be provided for each of the two sensor sections. In particular, this makes it possible to use a separate, technically different sensor element for each of the two sensor sections. This allows for a particularly variable design of the sensor arrangement for the scanning device according to the invention, adaptable to a wide variety of requirements. In both configurations, the sensor elements used can be provided as discrete components or integrated components, in particular fully integrated components. The scanning device according to the invention can also be characterized in that the sensor arrangement has a common sensor optic for the sensor sections, or that the sensor arrangement has a separate sensor optic for each of the sensor sections. The sensor optic maps the environment to be measured, in particular the area of ​​the environment that can be measured by the receiving area of ​​the respective sensor section, onto the corresponding sensor section. A single, common sensor optic allows, in particular, the entire sensor arrangement to be built in a particularly compact manner. Two separate sensor optics, on the other hand, can be used to enable a customized and needs-based mapping of the environment for each of the two sensor sections. Furthermore, the scanning device according to the invention can be characterized in that the sensor sections are positioned on different sides of the axis of rotation, preferably that the sensor sections are positioned symmetrically with respect to the axis of rotation. As already explained above, the determination of the stereo 3D data is based in particular on a difference in the viewing angle of the two sensor sections to the environment to be measured. By arranging the two sensor sections on different sides with respect to the axis of rotation, a particularly large distance between the sensor sections can be achieved while maintaining the same external dimensions of the scanning device according to the invention. A symmetrical arrangement of the two sensor sections, in turn, simplifies the evaluation of the acquired LiDAR and environmental data. The disclosure further comprises a method for spatially surveying an environment, wherein the method is carried out by a scanning device according to the invention. The method is characterized in that the LiDAR sensor unit of the scanning device acquires LiDAR data and performs a spatial survey of the environment based on this LiDAR data, wherein, in addition, optical environmental data of the environment are acquired by the second sensor section of the scanning device, and stereo 3D data are determined by the evaluation unit of the scanning device based on the LiDAR data and this additional environmental data from the second sensor section, and wherein the evaluation unit improves the survey of the environment by taking this stereo 3D data into account. The method is carried out by the scanning device according to the invention. All features and advantages described above with reference to the scanning device according to the invention can therefore also be achieved by the method. In the following, embodiments of the scanning device according to the invention are described by way of example with reference to schematic figures. Specifically, Fig. 1 shows a scanning device according to the invention scanning an environment, and Fig. 2 shows a representation of the LiDAR or environmental data acquired by the scanning device according to the invention in Fig. 1. Figures 1 and 2 schematically illustrate a scanning device 100 according to the invention and its operation. The scanning device 100 according to the invention is specifically designed to perform a method for spatially surveying an environment. Therefore, Figures 1 and 2 are described together below. The scanning device 100 according to the invention is shown spatially surveying an environment 200 in which three objects 210, 212, and 214 are present. The scanning device 100 according to the invention comprises, in particular, a LiDAR sensor unit 10 capable of performing a basic spatial survey of the environment 200. For this purpose, the LiDAR sensor unit 10 has a light source (not shown) for emitting transmitted light 20, which is reflected or re-emitted in the environment 200, in particular by objects 210, 212, 214 present in the environment 200, and is then detected as received light 22 by a receiving unit 12, in particular the first sensor section 40, of the LiDAR sensor unit 10. An evaluation unit 14, which is also part of the LiDAR sensor unit 10, evaluates the LiDAR data 70 (see Fig. 2) acquired by the receiving unit 12 and provides the spatial survey of the environment 200 as a result. However, particularly in the immediate vicinity of the scanning device 100 according to the invention, for example at a distance of up to 2 m around the scanning device 100, the resolution of the LiDAR sensor unit 10 used reaches its limits. Therefore, according to the invention, it is provided that further measurements are taken to improve the spatial surveying of the environment 200. In particular, the LiDAR sensor unit 10 has a sensor assembly 30 which is rotatably mounted about a rotational axis 48 in the LiDAR sensor unit 10 or the scanning device 100. This sensor assembly 30 has, in addition to the first sensor section 40 already mentioned above, a further optically sensitive second sensor section 44, wherein, as already described, the first sensor section 40 is formed by optically sensitive elements of the receiver unit 12. The second sensor section 44 can, for example, also be part of another LiDAR sensor unit or alternatively part of a background light measurement unit. As shown, the sensor arrangement 30 can have a single sensor element 32, wherein the two sensor sections 40, 44 are formed by spatially separated sections of the sensor element 32. Alternatively, but not shown, it is also possible that the sensor arrangement 30 has two sensor elements 32, wherein each of the sensor elements 32 then forms one of the two sensor sections 40, 44. A sensor optic 34 ensures that the incoming received light 22 is focused accordingly for both sensor sections 40, 44. As shown, a common sensor optic 34 can be provided for both sensor sections 40, 44. Alternatively, a separate sensor optic 34 can be installed for each of the two sensor sections 40, 44. During the rotation of the sensor arrangement 30 (see the two sub-figures A, B in Fig. 1), the first sensor section 40 acquires LiDAR data 70, and the second sensor section 44 acquires environmental data 72, which are then processed by the evaluation unit 14 into corresponding input images 60, 62 (see Fig. 2). Both sensor sections 40, 44 can have an optically sensitive area corresponding to a single pixel. In this case, the input images 60, 62 correspond to a line in the environment 200. Alternatively, the optically sensitive areas can also be configured as a column of pixels. In this case, a two-dimensional image of the environment 200 is generated as the respective input image 60, 62. In the latter configuration, the column of pixels can preferably be aligned parallel to the axis of rotation 48. The two sensor sections 40, 44 are arranged at a distance from each other in the sensor assembly 30 and are preferably readable separately. In addition to a horizontal distance, the two sensor sections 40, 44 can also be positioned vertically parallel to the axis of rotation 48 in the sensor assembly 30. The sensor sections 40, 44 can be read simultaneously or sequentially. In particular, as shown in Fig. 1, the two sensor sections 40, 44 are arranged at different positions with respect to the axis of rotation 48. The arrangement shown is on one side of the axis of rotation 48; however, it is also conceivable to arrange the first sensor section 40 on one side and the second sensor section 44 on the other side of the axis of rotation 48. Due to the spaced-apart arrangement, the two sensor sections 40, 44 also have different viewing directions 50, 52, along which a reception area of ​​the respective sensor section 40, 44 extends in the vicinity 200. Preferably, an angle Δα between the viewing directions can be between 15° and 45°. As described above, the sensor arrangement 30 is rotatably mounted about the axis of rotation 48. This allows the viewing directions 50, 52 of the two sensor sections 40, 44 to cover 200 different sensor areas 42, 46 in the surrounding environment. Preferably, the viewing directions 50, 52 of the two sensor sections 40, 44 are oriented transversely to the axis of rotation 48. In Fig. 1, sub-figures A and B show the sensor arrangement 30 in two different rotational positions. In an overlap area (not shown) of the two sensor areas 42, 46, both LiDAR data 70 of the first sensor section 40 and environmental data 72 of the second sensor section 44 are present.This overlap area represents a scan area of ​​the scanning device 100 according to the invention, in which the spatial measurement of the environment 200, made possible solely on the basis of the LiDAR data of the LiDAR sensor unit 10, can be improved by taking into account the environmental data 72 determined by the second sensor section 44. Preferably, the scan area can comprise at least 60°, but more preferably a larger area, for example 180° or even 360°, can also be covered by the scan area. The improvement in the measurement of the environment 200 made possible by the invention is based in particular on the different viewing directions 50, 52 of the two sensor sections 40, 44 as described above, or on the different positions of the sensor sections 40, 44. A possible procedure for the corresponding evaluation is shown in Fig. 2. The evaluation is carried out by the evaluation unit 14, which is designed accordingly. Figure 2 schematically shows input images 60 and 62, where the first input image 60 is formed from the LiDAR data 70 of the first sensor section 40 and thus depicts the sensor area 42 monitored by the first sensor section 40. Similarly, the second input image 62 is formed from the environmental data 72 of the second sensor section 44 and depicts the sensor area 46 monitored by the second sensor section 44. It is clearly evident that both sensor sections 40 and 44 detect the objects 210, 212, and 214 present in the environment 200, but due to their different positioning within the sensor arrangement 30, they detect objects at different rotational positions φ of the sensor arrangement 30. The difference is essentially determined by the angle Δα between the respective viewing directions 50 and 52 of the sensor sections 40 and 44.However, depending particularly on the distance of the respective object 210, 212, 214 to the scanning device 100, an additional offset 56 occurs. This offset 56 is greater the closer the respective object 210, 212, 214 is positioned in the vicinity 200 to the scanning device 100 (see Fig. 1). In particular, stereo 3D data 74, such as stereo distances of objects 210, 212, 214, can now be determined from this offset 56. This data can be used to improve the spatial measurement of the environment 200, as enabled solely by the LiDAR sensor unit 10. For example, LiDAR distance values ​​of objects 210, 212, 214, which are determined solely based on the LiDAR data 70 acquired by the LiDAR sensor unit 10, can be verified using the additionally available stereo distances. Verification could involve, for example, a plausibility check or the calculation of an average value, possibly weighted.An output image 64 generated by the evaluation unit 14, which corresponds to the overlap of the two input images 60, 62 and thus to a corresponding overlap of the sensor areas 42, 46 of the two sensor sections 40, 44, can in this way represent an improved measurement of the environment 200 by the determined stereo 3D data 74, for example in an output image 64 that includes a two-dimensional image of the environment 200 based on the input image 62, which is formed from the environment data 72 determined by the second sensor section 44, which is supplemented by additional, for example numerical, display of the stereo distances of objects 210, 212, 214, thus containing depth information which can be more accurate than the depth information of the LiDAR data 70. Reference sign 10 LiDAR sensor unit 12 Receiver unit 14 Evaluation unit 20 Transmitting light 22 Received light 30 Sensor arrangement 32 Sensor element 34 Sensor optics 40 First sensor section 42 Sensor area (first sensor section) 44 Second sensor section 46 Sensor area (second sensor section) 48 Rotation axis 50 Viewing direction (first sensor section) 52 Viewing direction (second sensor section) 54 Angle Δα 56 Offset 60 First input image 62 Second input image 64 Output image 70 LiDAR data 72 Environment data 74 Stereo 3D data 100 Scanning device 200 Environment 210 Object A 212 Object B 214 Object C

Claims

Scanning device (100) for spatial surveying of an environment (200), comprising a LiDAR sensor unit (10) with a light source for emitting transmitting light (20) into the environment (200), a receiving unit (12) for receiving transmitted light (20) remitted and / or reflected in the environment (200) as received light (22), and an evaluation unit (14), wherein the evaluation unit (14) is configured for evaluating the LiDAR data (70) acquired by the receiving unit (12) for spatial surveying of the environment (200), characterized in that the LiDAR sensor unit (10) comprises an optical sensor arrangement (30) rotatably mounted about a rotational axis (48) with two sensor sections (40, 44), wherein the sensor sections (40, 44) are spaced apart from each other and arranged at different positions with respect to the rotational axis (48). are,wherein a first of the sensor sections (40) is formed by optically sensitive elements of the receiving unit (12) and determines the LiDAR data (70), wherein furthermore a second of the sensor sections (44) determines optical environmental data (72), and wherein the evaluation unit (14) is configured for evaluating the environmental data (72), and further configured, based on the LiDAR data (70) and the environmental data (72), for determining stereo 3D data (74) to improve the spatial measurement of the environment (200). Scanning device (100) according to claim 1, characterized in that the evaluation unit (14) is configured to perform the improvement, in particular only if a signal strength of the received light (22) and / or a ratio of a measurement signal to the noise of the received light (22) in the receiving unit (12) of the LiDAR sensor unit (10) falls below a predetermined threshold value, and / or if a signal strength of the received light (22) in the receiving unit (12) of the LiDAR sensor unit (10) exceeds a predetermined threshold value, and / or if a LiDAR distance determined by the LiDAR sensor unit (10) and / or a stereo distance contained in the stereo 3D data (74) falls below a predetermined distance threshold value. Scanning device (100) according to claim 1 or 2, characterized in that the respective viewing directions (50, 52) of the two sensor sections (40, 44), along which the respective sensor section is sensitive, include an angle Δα (56), preferably an angle Δα (56) between 15° and 45°. Scanning device (100) according to claim 3, characterized in that the viewing direction (50, 52) of at least one of the sensor sections (40, 44) is aligned transversely to the axis of rotation (48), preferably the viewing directions (50, 52) of both sensor sections (40, 44) are aligned transversely to the axis of rotation (48). Scanning device (100) according to one of the preceding claims 1 to 4, characterized in that during the rotational movement of the sensor arrangement (30) the two sensor sections (40, 44) each acquire a plurality of individual images as LiDAR data (70) and environmental data (72), wherein the evaluation unit (14) is configured to generate a first input image (60) from the individual images of the first sensor section (40) and to generate a second input image (62) from the individual images of the second sensor section (44), and wherein the evaluation unit (14) is configured to generate an output image (64) from the first input image (60) and the second input image (62). Scanning device (100) according to claim 5, characterized in that the output image (64) comprises the improved measurement of the environment (200) by the determined stereo 3D data (74), preferably that the output image (64) corresponds to the improved measurement of the environment (200) by the determined stereo 3D data (74). Scanning device (100) according to claim 5 or 6, characterized in that the scanning device (100) has an output interface that communicates with the evaluation unit (14) for outputting the first input image (60) and / or the second input image (62) and / or the output image (64). Scanning device (100) according to one of the preceding claims 1 to 7, characterized in that an optically sensitive area of ​​the two sensor sections (40, 44) each corresponds to a single pixel. Scanning device (100) according to one of the preceding claims 1 to 7, characterized in that an optically sensitive area of ​​the two sensor sections (40, 44) each corresponds to a column of pixels, wherein the pixels in the column are arranged along a longitudinal extent, and wherein preferably the longitudinal extent of the respective column is aligned parallel to the axis of rotation (48) of the sensor arrangement (30). Scanning device (100) according to one of the preceding claims 1 to 9, characterized in that the second sensor section (44) is designed as a component of one of the following sensor units: - component of a LiDAR sensor unit - component of a background light measurement unit Scanning device (100) according to one of the preceding claims 1 to 10, characterized in that the sensor sections (40, 44) are arranged vertically spaced apart parallel to the axis of rotation (48) of the sensor arrangement (30). Scanning device (100) according to one of the preceding claims 1 to 11, characterized in that the sensor arrangement (30) has an optical sensor element (32), wherein the sensor sections (40, 44) are designed as geometrically spaced sections of the sensor element (32), or that the sensor arrangement (30) has two geometrically separate optical sensor elements (32), wherein each sensor element (32) comprises one of the sensor sections (40, 44). Scanning device (100) according to one of the preceding claims 1 to 12, characterized in that the sensor arrangement (30) has a common sensor optic (34) for the sensor sections (40, 44), or that the sensor arrangement (30) has a separate sensor optic (34) for each of the sensor sections (40, 44). Scanning device (100) according to one of the preceding claims 1 to 13, characterized in that the sensor sections (40, 44) are positioned on different sides of the axis of rotation (48), preferably that the sensor sections (40, 44) are positioned symmetrically with respect to the axis of rotation (48).

Images