Lidar sensor system for a vehicle, vehicle, and method for operating a lidar sensor system

Abstract

A lidar sensor system (2) has a transmission device (6), a detector array (7), a light deflection device (8), and an evaluation unit (10). For each of a plurality of vertical positions on the detector array (7), an associated horizontal read-out region (13, 17a, 17b, 17c) is specified on the detector array (7). The evaluation unit (10) is configured to read out, for each vertical position for a current position of the light deflection device (8), those optical detectors which lie in the horizontal read-out region (13, 17a, 17b, 17c) of the respective vertical position, and to determine an intensity value on the basis thereof. For each of the plurality of vertical positions, a horizontal reference position (14) at which a maximum incident light intensity is expected is specified on the detector array (7). For a first vertical region of the detector array (7), the horizontal read-out region (13, 17a, 17b, 17c) contains the horizontal reference position (14), and, for a second vertical region, the horizontal read-out region (13, 17a, 17b, 17c) does not contain the horizontal reference position (14).

Description

[0001] 2023PF01547

[0002] 1

[0003] Lidar sensor system for a vehicle, vehicle and method for operating a lidar sensor system

[0004] The present invention relates to a lidar sensor system for a vehicle comprising a transmitter, a detector array, a light deflection device, and an evaluation unit. The invention further relates to a vehicle with such a lidar sensor system and a corresponding method for operating a lidar sensor system.

[0005] The arrangement of the transmitter and detector array plays a crucial role in lidar sensor systems, particularly laser scanners. The goal is typically to align the detector array with the maximum intensity of the incident laser beam to achieve the lowest possible signal-to-noise ratio and thus the greatest possible range. However, it has been shown that such an arrangement can also lead to high intensity in areas of the field of view with highly reflective objects, such as road markings at close range, and on surfaces with lower reflectivity, such as asphalt. This results in a reduction of contrast in the corresponding area. Consequently, for example, road markings can be difficult to distinguish from asphalt surfaces.

[0006] It is an object of the present invention to increase the intensity difference detected by a lidar sensor system between highly reflective and less reflective objects, in particular without having to accept a reduced range in other areas of the field of view.

[0007] This problem is solved by the respective subject matter of the independent claims. Advantageous further developments and preferred embodiments are the subject matter of the dependent claims.

[0008] The invention is based on the idea of ​​positioning the horizontal readout area on the detector array differently for different vertical areas on the detector array relative to a predetermined reference position that corresponds to an expected maximum light intensity on the detector array. 2023PF01547

[0009] 2

[0010] According to one aspect of the invention, a lidar sensor system for a vehicle, in particular a motor vehicle, is provided. The lidar sensor system comprises a transmitter, a detector array, a light deflection device, and an evaluation unit. The transmitter is configured to emit light into the environment of the lidar sensor system, in particular the external environment of the vehicle. The light deflection device is configured to assume different positions and, depending on its position in the environment, to direct reflected portions of the emitted light onto the detector array at different horizontal angles of incidence. Different vertical positions on the detector array correspond to different vertical angles of incidence of the reflected portions of the light.

[0011] For a multitude of vertical positions on the detector array, a corresponding horizontal readout area is defined on the detector array. The evaluation unit is configured to read out, for each vertical position of the multitude of vertical positions and for a current position of the light deflection device, those optical detectors that lie within the horizontal readout area of ​​the respective vertical position, and, depending on the result of the readout, to determine an intensity value for the horizontal angle of incidence corresponding to the current position and the vertical angle of incidence corresponding to the respective vertical position.

[0012] For each of the multiple vertical positions, a horizontal reference position is defined on the detector array where maximum incident light intensity is expected. For a first subset of the multiple vertical positions, where the first subset corresponds to a first vertical region, in particular a contiguous first vertical region, of the detector array, the respective horizontal readout region includes the respective horizontal reference position. For a second subset of the multiple vertical positions, which corresponds to a second vertical region, in particular a contiguous second vertical region, of the detector array, the respective horizontal readout region does not include the respective horizontal reference position.

[0013] A known design of lidar systems are so-called laser scanners, in which a laser beam is deflected by means of a light deflection device, so that different deflection angles of the laser beam can be achieved. In particular, the lidar sensor system according to the invention is designed as a laser scanner. The light deflection device can be 2023PF01547

[0014] 3. For example, the light deflection device may contain a rotatably mounted mirror. Alternatively, the light deflection device may have a mirror element with a tiltable and / or pivotable surface. The mirror element may, for example, be designed as a microelectromechanical system (MEMS). In the environment, the emitted laser beams may be partially reflected, and the reflected components may again strike the laser scanner, in particular the light deflection device, which can direct them onto the detector array. Each optical detector of the detector array generates, in particular, a corresponding detector signal based on the components detected by the respective optical detector.Based on the spatial arrangement of the respective detector, together with the current position of the light deflection device, in particular its rotational or tilting and / or swiveling position, the direction of incidence of the detected reflected components can be determined. The evaluation unit can also, for example, perform a time-of-flight measurement to determine the radial distance of the reflecting object. Alternatively or additionally, a method can be used to determine the distance by evaluating the phase difference between emitted and detected light.

[0015] Here and in the following, the term "light" can be understood to encompass electromagnetic waves in the visible, infrared, and / or ultraviolet ranges. Accordingly, the term "optical" can also be understood to refer to light as defined in this way. The light emitted by the transmitting device, for example, is infrared light.

[0016] The evaluation unit is, in particular, a data processing device which can be part of a data processing system.

[0017] A data processing device may, in particular, comprise one or more computers, one or more microcontrollers, and / or one or more integrated circuits, for example, one or more application-specific integrated circuits (ASICs), one or more field-programmable gate arrays (FPGAs), and / or one or more systems-on-a-chip (SoCs). A data processing device may also include one or more processors, for example, one or more microprocessors, one or more central processing units (CPUs), one or more graphics processing units (GPUs), and / or one or more signal processors, in particular one or more digital signal processors (DSPs). The data processing device may also include a 2023PF01547

[0018] 4 physical or virtual clusters of computers or other devices mentioned.

[0019] A data processing device may also include one or more hardware and / or software interfaces, for example for receiving and / or providing data.

[0020] A data processing device may also include one or more storage devices. A storage device may be implemented as volatile memory, such as dynamic random access memory (DRAM) or static random access memory (SRAM), or as non-volatile data storage, such as read-only memory (ROM), programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), flash memory or flash EEPROM, ferroelectric random access memory (FRAM), magnetoresistive random access memory (MRAM), or phase-change random access memory (PCRAM).

[0021] The different positions of the light deflection device correspond to different horizontal angles of incidence at which the emitted and reflected light enters the lidar sensor system and is directed onto the detector array. The position of the light deflection device is changed, in particular, successively or continuously, so that a horizontal angular range in the environment is sampled or scanned. Scanning in the vertical direction is not required; rather, for a given horizontal angle of incidence, the detector array receives light from vertical angles of incidence across the entire field of view.

[0022] The detector array is, in particular, a rectangular array with a plurality of rows and columns, wherein the detector array comprises a plurality of optical detectors, each defined by a combination of row and column. It should be noted that an optical detector need not necessarily consist of a single diode or the like, but may also contain multiple diodes, in particular single-photon avalanche diodes (SPADs). In other words, a pixel of the detector array defined by a row and a column may have a subpixel structure. However, this is not the case in every embodiment; rather, it may also be the case that each pixel comprises exactly one photodiode, in particular an avalanche photodiode (APD).

[0023] 5 corresponds. Depending on the embodiment, the detector array can have several tens or several hundred rows and / or several tens or several hundred columns.

[0024] Different horizontal positions on the detector array correspond to different columns, and different vertical positions correspond to different rows. The terms "vertical" and "horizontal" refer here and in the following to the intended mounting of the lidar sensor system on the vehicle. Specifically, the horizontal direction, i.e., the rows of the detector array, is perpendicular to the vehicle's vertical axis. The vertical direction, and consequently the columns of the detector array, are parallel to the vehicle's vertical axis. The vehicle's vertical axis can be understood here and in the following as pointing away from the surface on which the vehicle is standing. Based on this understanding, the terms "top" and "bottom" can also be understood here and in the following as referring to the detector array.

[0025] The intensity value is, in particular, a measure of the intensity or energy of the light detected by the optical detectors in the corresponding horizontal readout range. The intensity value can be determined, for example, by averaging the individual intensity values ​​of the individual optical detectors or by some other method of calculating these individual intensity values.

[0026] The horizontal readout area for a given vertical position on the detector array can, in principle, consist of a single pixel of the detector array or an entire row of the detector array. Preferably, however, the horizontal readout area includes a number of pixels in a row of the detector array that are related and include several pixels of said row, but not all pixels of said row. This is because, typically, the reflected laser beam illuminates the area of ​​the detector array relatively inhomogeneously, or not completely, particularly in the horizontal direction.With regard to the signal-to-noise ratio, it is therefore advantageous to exclude pixels with low expected light intensity from the horizontal readout area and, conversely, to include the horizontal reference position, where the maximum incident light intensity of the reflected laser beam is expected, in the horizontal readout area. This is particularly the case for the first vertical region of the detector array. 2023PF01547.

[0027] 6

[0028] However, it has been found that this seemingly optimal positioning of the horizontal readout area can be disadvantageous, particularly in the near field of view of the lidar sensor system, for example, when detecting lane markings on the road ahead of the vehicle. These lane markings are highly reflective objects. If, however, the intensity of reflected light is generally very high in such areas, as is the case in the near field, then a relatively large amount of light may also be reflected by less reflective objects, such as the road surface. Consequently, the contrast between highly reflective objects like lane markings and surrounding less reflective objects like the road surface decreases.This means that downstream algorithms for object detection or object tracking, or the like, are less able to reliably distinguish the aforementioned highly reflective objects from other objects.

[0029] According to the invention, this disadvantage is overcome by shifting the horizontal readout area relative to the horizontal reference position in the second area of ​​the detector array in such a way as to achieve the seemingly optimal positioning, such that it no longer includes the horizontal reference position. In other words, the intensity level of the detected light is intentionally reduced to achieve a higher contrast between highly reflective and weakly reflective areas or objects. However, this is not done in the first area of ​​the detector array in order to avoid a reduction in range in less critical areas of the field of view.

[0030] The detector array can generate a corresponding detector signal for each optical detector or pixel. The reading of a specific pixel or area can be understood here and in the following as meaning that the detector signals of the read-out pixels or area, and in particular only these, are considered by the evaluation unit to determine the intensity value. In other words, the horizontal readout areas define those pixels of the detector array that are, in effect, activated, whereas the other pixels of the detector array are not considered or are deactivated. The readout can be implemented, for example, via registers or other storage devices assigned to the individual pixels, and / or by electronic shutter mechanisms. 2023PF01547

[0031] 7

[0032] The horizontal reference position and its path across the various rows of the detector array result from the geometric arrangement of the detector array relative to the transmitting device, in particular the one or more light sources of the transmitting device and, if applicable, optical components for beam shaping, beam guidance, or the like. The geometry or arrangement of the light deflection device, especially the mirror, may also influence the horizontal reference position. In some lidar sensor systems, the detector array and the light source(s) are arranged one above the other. In such embodiments, the horizontal reference position for all rows of the detector array lies, for example, in the same column.In embodiments in which the detector array and the one or more light sources are separate from each other, in particular side by side and spaced apart from each other, a more or less strongly curved curve results, on which the horizontal reference positions lie across the different lines.

[0033] According to at least one embodiment, the light deflection device has a rotatably mounted mirror, and the different positions of the light deflection device correspond to different rotational positions of the mirror.

[0034] According to at least one embodiment, the lidar sensor system has a control unit configured to control the light deflection device, so that the light deflection device is successively moved into a multitude of different positions.

[0035] The control unit can be another data processing device, for example, part of the data processing system. In some embodiments, the control unit and the evaluation unit can also be combined in a single data processing device.

[0036] If the light deflection device has a rotatably mounted mirror, the control unit is specifically designed to control the mirror for rotation, so that it is successively moved into a multitude of different rotational positions.

[0037] The different positions of the light deflection device or rotation positions of the mirror can be interpreted as different successive frames. For example, it is possible that the positions of the 2023PF01547

[0038] 8

[0039] The light deflection device is continuously changed, but the corresponding readouts take place at discrete times or over defined periods of time.

[0040] The evaluation unit is designed to read out, for each vertical position of the multitude of vertical positions of the light deflection device, those optical detectors that lie in the horizontal readout range of the respective vertical position, and to determine, depending on this, an intensity value for the horizontal angle of incidence corresponding to the respective position and the vertical angle of incidence corresponding to the respective vertical position.

[0041] In other words, this allows the horizontal field of view of the lidar sensor system to be scanned. The horizontal readout areas, in particular, remain unchanged.

[0042] According to at least one embodiment, the evaluation unit is designed to detect an object on the road surface, depending on the progression of the determined intensity values ​​for the second vertical area across the multitude of different positions, i.e., across the various horizontal angles of incidence.

[0043] The evaluation unit can employ known algorithms for edge detection or similar methods. The increased contrast between different objects on the road surface, particularly road markings and asphalt or other road surfaces, as described in the invention, enhances the reliability and accuracy of object detection.

[0044] According to at least one embodiment, the horizontal selection areas are identical for all vertical positions of the second part of the plurality of vertical positions.

[0045] This simplifies the selection logic.

[0046] According to at least one embodiment, the respective horizontal readout area for a third part of the plurality of vertical positions includes a third vertical area, in particular a contiguous third vertical area of ​​the detector array, which does not include the respective horizontal reference position.

[0047] The statements regarding the second part of the plurality of vertical positions, or the second vertical area, can be applied analogously to the third part of the plurality of vertical positions and the third vertical area. 2023PF01547

[0048] 9

[0049] In such embodiments, the trade-off between maximum range and increased contrast can be made in a more targeted or individual manner for different areas of the vertical field of view of the lidar sensor system.

[0050] According to at least one embodiment, the horizontal selection areas are identical for all vertical positions of the third part of the plurality of vertical positions.

[0051] This also allows the evaluation logic to be simplified here.

[0052] According to at least one embodiment, the horizontal readout areas for all vertical positions of the third part of the plurality of vertical positions are horizontally shifted relative to the horizontal readout areas of the vertical positions of the second part of the plurality of vertical positions.

[0053] This is particularly advantageous if the horizontal reference positions do not lie in the same column across all rows of the detector array, but, for example, as described above, on the curved line. This makes it possible, in particular, to achieve a less significant difference between the horizontal readout positions and the horizontal reference positions for the second and third vertical regions on the detector array.

[0054] According to another aspect of the invention, a vehicle is specified which has a lidar sensor system according to the invention.

[0055] The vehicle is, in particular, a motor vehicle, for example, a car, especially a passenger car or truck, or a motorcycle. The lidar sensor system is, in particular, mounted on the vehicle as intended. Specifically, the lidar sensor system is mounted at a front end of the vehicle, for example, integrated into or attached to a bumper or radiator grille or a corresponding area at the front end of the vehicle. Accordingly, the vertical field of view of the lidar sensor system includes at least part of a roadway on which the vehicle is located and, for example, an area above the horizon. 2023PF01547

[0056] 10

[0057] For example, the first vertical area on the detector array can correspond to the area of ​​the vertical field of view above the horizon, and the second vertical area of ​​the detector array can correspond to an area of ​​the roadway in front of the vehicle.

[0058] For example, the lidar sensor system is mounted on the vehicle such that the columns of the detector array are oriented perpendicular to the vehicle's vertical axis. Alternatively, the lidar sensor system can be mounted on the vehicle such that the rows of the detector array are oriented parallel to the vehicle's vertical axis.

[0059] Further embodiments of the vehicle according to the invention follow directly from the various configurations of the lidar sensor system according to the invention, and vice versa. In particular, individual features and corresponding explanations as well as advantages relating to the various embodiments of the lidar sensor system according to the invention can be transferred analogously to corresponding embodiments of the vehicle according to the invention.

[0060] According to a further aspect of the invention, a method for operating a lidar sensor system for a vehicle is described. In this method, light is emitted into the environment of the lidar sensor system, particularly the vehicle, by means of a transmitter device of the lidar sensor system. A light deflection device of the lidar sensor system is successively moved into a multitude of different positions, whereby, depending on the position of the light deflection device in the environment, reflected components of the emitted light with different horizontal angles of incidence are directed onto a detector array of the lidar sensor system. Different vertical positions on the detector array correspond to different vertical angles of incidence of the reflected components.

[0061] For a multitude of vertical positions on the detector array, a corresponding horizontal readout area is defined. For each vertical position within the multitude of vertical positions for a given position of the light deflection device, those optical detectors located within the horizontal readout area of ​​the respective vertical position are read out, and an intensity value is determined for the horizontal angle of incidence corresponding to the current position and the vertical angle of incidence corresponding to the respective vertical position. 2023PF01547

[0062] 11

[0063] For each of the multiple vertical positions, a horizontal reference position is defined on the detector array where maximum incident light intensity is expected. For the first part of the multiple vertical positions, corresponding to a first vertical region of the detector array, the respective horizontal readout region includes the respective horizontal reference position. For the second part of the multiple vertical positions, corresponding to a second vertical region of the detector array, the respective horizontal readout region does not include the respective horizontal reference position.

[0064] According to at least one embodiment of the method, for each vertical position of the plurality of vertical positions, for each of the plurality of positions of the light deflection device, those optical detectors are read out which lie in the horizontal readout range of the respective vertical position, and depending on this, an intensity value is determined for the horizontal angle of incidence corresponding to the respective position and the vertical angle of incidence corresponding to the respective vertical position.

[0065] According to at least one embodiment, the horizontal reference positions for the multitude of vertical positions are determined depending on a spatial arrangement of the detector array and the transmitting device relative to each other.

[0066] Further embodiments of the method according to the invention follow directly from the various configurations of the lidar sensor system according to the invention, and vice versa. In particular, individual features and corresponding explanations as well as advantages relating to the various configurations of the lidar sensor system according to the invention can be transferred analogously to corresponding configurations of the method according to the invention. In particular, the lidar sensor system according to the invention is configured or programmed to carry out a method according to the invention. In particular, the lidar sensor system according to the invention carries out the method according to the invention.

[0067] Further features of the invention are apparent from the claims, the figures, and the description of the figures. The features and combinations of features mentioned above in the description, as well as the features and combinations of features mentioned below in the description of the figures and / or illustrated in the figures, may be encompassed by the invention not only in the combinations specified, but also in other combinations. In particular, embodiments and 2023PF01547

[0068] 12

[0069] Combinations of features that do not include all features of an originally formulated claim may be encompassed by the invention. Furthermore, embodiments and combinations of features that go beyond or deviate from the combinations of features specified in the claims may also include the invention.

[0070] The invention is explained in more detail below with reference to specific exemplary embodiments and corresponding schematic drawings. Identical or functionally equivalent elements in the drawings may be provided with the same reference numerals. The description of identical or functionally equivalent elements is not necessarily repeated with respect to the different figures.

[0071] The figures show:

[0072] Fig. 1 shows a schematic representation of a vehicle with an exemplary embodiment of a lidar sensor system according to the invention;

[0073] Fig. 2 shows a schematic representation of a detector array of a lidar sensor system with a conventional definition of horizontal readout areas;

[0074] Fig. 3 shows a schematic progression of an intensity value over different horizontal angles of incidence for the definition of the horizontal readout ranges according to Fig. 2;

[0075] Fig. 4 shows a schematic representation of a detector array of a lidar sensor system with a definition of horizontal readout areas according to an exemplary embodiment of a lidar sensor system according to the invention;

[0076] Fig. 5 shows a schematic curve of an intensity value over different horizontal angles of incidence for the definition of the horizontal readout ranges according to Fig. 4; and 2023PF01547

[0077] 13

[0078] Fig. 6 shows a schematic representation of a detector array of a lidar sensor system with a definition of horizontal readout areas according to a further exemplary embodiment of a lidar sensor system according to the invention.

[0079] Figure 1 schematically depicts a vehicle 1, which has an exemplary embodiment of a lidar sensor system 2 according to the invention. x denotes a longitudinal axis of the vehicle 1 and y a transverse axis of the vehicle 1. A vertical axis z of the vehicle 1 is perpendicular to the longitudinal axis x and the transverse axis y and points, for example, out of the plane of the image. The vehicle 1 is located, in particular, on a roadway 3 with a road surface 5, for example asphalt, and road markings 4. Block 11 schematically represents an area of ​​interest in the field of view of the lidar sensor system 2 for detecting one of the road markings 4. The lidar sensor system 2 has a transmitter 6 with one or more laser diodes and a detector array 7, which has a plurality of rows and a plurality of columns that define the corresponding pixels of the detector array 7.

[0080] The lidar sensor system 2 is mounted on the vehicle 1 such that the lines of the detector array 7 are oriented perpendicular to the vehicle's vertical axis z, for example parallel or substantially parallel to the vehicle's transverse axis y. The lines of the detector array are accordingly oriented, for example, parallel to the vehicle's vertical axis z.

[0081] For example, the transmitter 6 and the detector array 7 can be arranged one above the other along the vehicle's vertical axis z, but other arrangements are also possible.

[0082] The transmitting device 6 is configured to emit light into the vicinity of the lidar sensor system 2 and, consequently, the vicinity of the vehicle 1. According to the vertical field of view of the lidar sensor system 2, a portion of the emitted light strikes the roadway 3, in particular the road surface 5 and the lane markings 4, and can be reflected by them. The corresponding area of ​​the vertical field of view can also be referred to as the near field or ground field. Furthermore, another portion of the emitted light is directed into a 2023PF01547

[0083] 14

[0084] emitted in the far range of the vertical field of vision, which lies particularly above lane 3 or above a horizon or horizon line, and can be reflected by other objects, for example other vehicles, traffic signs, buildings and so on.

[0085] The lidar sensor system 2 also includes, for example, a control unit 9 configured to actuate the light deflection device 8 in order to position it differently. The light deflection device 8 can, for example, have a rotatably mounted mirror, and the control unit 9 can actuate the rotatably mounted mirror so that it rotates around the axis of rotation and thus assumes different positions. Depending on the position of the light deflection device 8, reflected light with different horizontal angles of incidence is directed onto the detector array 7. Different vertical positions on the detector array 7, on the other hand, correspond to different vertical angles of incidence of the reflected components of the light.

[0086] For a plurality of vertical positions on the detector array 7, in particular for all rows of the detector array 7, a corresponding horizontal readout area 13, 17a, 17b, 17c is defined on the detector array 7. The lidar sensor system 2 also has an evaluation unit 10, which is configured to read out, for each vertical position of the plurality of vertical positions for a current position of the light deflection device 8, those optical detectors that lie within the horizontal readout area 13, 17a, 17b, 17c of the respective vertical position. Depending on the correspondingly readout detector values ​​or detector signals, the evaluation unit 10 can determine an intensity value for the horizontal angle of incidence corresponding to the current position and the vertical angle of incidence corresponding to the respective vertical position.By changing the positions of the light deflection devices 8, such an intensity value can also be determined accordingly for different horizontal angles of incidence.

[0087] Fig. 2 schematically shows the position of the horizontal readout areas 13 for a lidar sensor system 2 not designed according to the invention. For each vertical position of the plurality of vertical positions, a horizontal reference position 14 is specified on the detector array 7, at which, according to the geometric arrangement of the transmitter 6 and the detector array 7 relative to each other, a maximum incident light intensity of the reflected components of the emitted light 2023PF01547

[0088] 15 is expected. In the example of Fig. 2, this is in particular a straight line that corresponds to a column of the detector array 7. This can be the case, for example, if the transmitter 6 and the detector array 7 are arranged one above the other along the vehicle's vertical axis z.

[0089] The region 12 shown in Fig. 2 corresponds to a region where a light intensity is expected to exceed a certain threshold. In simpler terms, region 12 corresponds to the area where the reflected components of the emitted light occur, whereas outside region 12 the incident light can be neglected.

[0090] As shown in Fig. 2, the horizontal readout areas 13 do not cover the entire area 12. In the example of Fig. 2, the horizontal readout areas 13 lie within a rectangle centered around the horizontal reference positions. In other words, the horizontal readout area is identical for all vertical positions, or all rows of the detector array 7, and includes the horizontal reference position 14. This ensures that the signal-to-noise ratio is as high as possible, especially in the far range, resulting in a particularly long range for the lidar sensor system 2.

[0091] A disadvantage, however, is the potentially low contrast between highly reflective objects such as the road marking 4 and less reflective objects such as the road surface 5 in the immediate vicinity. This is shown schematically in Fig. 3. In Fig. 3, the intensity value is plotted against the horizontal angle of incidence on the vertical axis. Area 15 corresponds to the road marking 4, and areas 16 correspond to the road surface 5. A difference in intensity can be seen between areas 15 and 16, but the difference is not very pronounced, which makes the detection of the road marking 4 more difficult.

[0092] Figure 4 schematically illustrates a situation in which the horizontal readout areas 17a, 17b are defined according to the invention. In a first vertical area of ​​the detector array 7, the horizontal readout areas 17a are defined in the same way as in the conventional case of Figure 2. The first area corresponds in particular to the far area above the roadway 3. In a second area, which in particular 2023PF01547

[0093] While the horizontal readout areas 16 lie below the first area, the horizontal readout areas 17 are shifted with respect to the horizontal reference position 14 in such a way that the horizontal readout areas 17b do not include the horizontal reference position 14. Furthermore, the horizontal readout areas 17b in the second area can be the same for all lines and can also have the same width as the horizontal readout areas 17a in the first area of ​​the detector array 7.

[0094] This reduces the overall intensity level in the horizontal readout areas 17b in the second vertical region of the detector array, resulting in a higher contrast in intensity value between highly reflective objects such as the road marking 4 and less strongly reflective objects such as the road surface 5, as shown schematically in Fig. 5 for the inventive definition of the horizontal readout areas 17a, 17b from Fig. 4, analogous to Fig. 3.

[0095] Figure 6 shows a situation in which the geometric arrangement of the transmitter 6 and the detector array 7 differs from that described in Figures 2 to 5. In particular, the transmitter 6 and the detector array 7 can be arranged separately from each other, i.e., not one above the other, but at different positions in the xy-plane. An advantage of such an arrangement is the reduced height of the lidar sensor system 2.

[0096] This results in the area 12, on which the reflected light is incident, no longer being a rectangle, but rather horizontally shifted or curved in the near field. Accordingly, the horizontal reference position 14 is also no longer a straight line, but a curved line. In this case as well, the horizontal readout areas 17a for the first vertical area of ​​the detector array 7 are defined such that they include the horizontal reference position 14, and the horizontal readout areas 17b of the second vertical area of ​​the detector array 7 are defined such that they do not include the horizontal reference position 14. However, due to the curved line on which the horizontal reference positions 14 lie, the shift of the horizontal readout areas 17b of the second vertical area relative to the horizontal readout areas 17a of the first vertical area can be smaller than shown in Fig. 4. 2023PF01547

[0097] 17

[0098] It is also possible that the near range on the detector array 7 is not only defined by the second vertical range, but by several vertical ranges, in which a different definition of the horizontal readout ranges may be provided. In the example of Fig. 6, horizontal readout ranges 17c are shown for a third vertical range of the detector array 7, which lies below the second vertical range. The horizontal readout ranges 17c of the third vertical range also do not include the respective horizontal reference position 14. However, the displacement of the horizontal readout ranges 17c in the third vertical range relative to the horizontal readout ranges 17a of the first vertical range may differ from that for the second vertical range.In particular, this makes it possible to ensure that the distances between the horizontal readout areas 17b, 17c and the horizontal reference positions 14 differ less significantly.

[0099] As described, particularly with regard to the figures, the invention makes it possible to increase the intensity difference detected by a lidar sensor system between highly reflective and less reflective objects, in particular without having to accept a reduced range in other areas of the field of view.

[0100] In various embodiments, the optimal definition of the horizontal readout areas with respect to the signal-to-noise ratio can be determined, and for a part of the detector array 7, which corresponds to the near range below the horizon, deviations can be made to increase the contrast accordingly.

Claims

2023PF01547 18 Patentansprüche 1. Lidar sensor system (2) for a vehicle (1) comprising a transmitter (6), a detector array (7), a light deflection device (8), and an evaluation unit (10), wherein the transmitter (6) is configured to emit light into the vicinity of the lidar sensor system (2); the light deflection device (8) is configured to assume different positions and, depending on the position, to direct reflected components of the emitted light at different horizontal angles of incidence onto the detector array (7); different vertical positions on the detector array (7) correspond to different vertical angles of incidence of the reflected components; for a plurality of vertical positions on the detector array (7), a corresponding horizontal readout area (13, 17a, 17b, 17c) is defined on the detector array (7);the evaluation unit (10) is configured to read out, for each vertical position of the plurality of vertical positions for a current position of the light deflection device (8), those optical detectors which lie in the horizontal readout area (13, 17a, 17b, 17c) of the respective vertical position, and, depending on this, to determine an intensity value for the horizontal angle of incidence corresponding to the current position and the vertical angle of incidence corresponding to the respective vertical position; for each plurality of vertical positions, a horizontal reference position (14) is specified on the detector array (7) at which a maximum incident light intensity is expected; for a first part of the plurality of vertical positions, corresponding to a first vertical area of ​​the detector array (7), the respective horizontal readout area (13, 17a, 17b, 17c) contains the respective horizontal reference position (14); and; 2023PF01547 19 for a second part of the multitude of vertical positions corresponding to a second vertical area of ​​the detector array (7) the respective horizontal readout area (13, 17a, 17b, 17c) does not include the respective horizontal reference position (14).

2. Lidar sensor system (2) according to claim 1, wherein different vertical positions on the detector array (7) correspond to different rows of the detector array (7); and different horizontal positions on the detector array (7) correspond to different columns of the detector array (7).

3. Lidar sensor system (2) according to one of the preceding claims, wherein the lidar sensor system (2) has a predetermined mounting orientation for mounting on the vehicle (1 ), such that the columns of the detector array (7) are oriented perpendicular to a vehicle vertical axis of the vehicle (1 ); and the first vertical region is located above the second vertical region with respect to the vehicle vertical axis.

4. Lidar sensor system (2) according to one of the preceding claims, wherein the horizontal reference positions (14) are located in a common column of the detector array (7); or the horizontal reference positions (14) are located on a common curve.

5. Lidar sensor system (2) according to one of the preceding claims, wherein the light deflection device (8) has a rotatably mounted mirror (8) and different positions of the light deflection device (8) correspond to different rotational positions of the mirror (8).

6. Lidar sensor system (2) according to one of the preceding claims, wherein the lidar sensor system (2) comprises a control unit (9) configured to control the light deflection device (8) in order to successively move the light deflection device (8) into a plurality of different positions; the evaluation unit (10) configured to read out, for each vertical position of the plurality of vertical positions of the light deflection device (8), those optical detectors which are located in the 2023PF01547 20 horizontal selection range (13, 17a, 17b, 17c) of the respective vertical position, and depending on this, an intensity value for the horizontal angle of incidence corresponding to the respective position and the vertical angle of incidence corresponding to the respective vertical position is to be determined.

7. Lidar sensor system (2) according to claim 6, wherein the evaluation unit (10) is configured to detect an object (4) on a road surface (5) depending on a progression of the determined intensity values ​​for the second vertical area over the multitude of different positions.

8. Lidar sensor system (2) according to claim 7, wherein the object (4) is a road marking (4).

9. Lidar sensor system (2) according to one of the preceding claims, wherein the horizontal readout areas (13, 17a, 17b, 17c) are identical for all vertical positions of the second part of the plurality of vertical positions.

10. Lidar sensor system (2) according to claim 9, wherein for a third part of the plurality of vertical positions corresponding to a third vertical area of ​​the detector array (7) the respective horizontal readout area (13, 17a, 17b, 17c) does not include the respective horizontal reference position (14); and the horizontal readout areas (13, 17a, 17b, 17c) are identical for all vertical positions of the third part of the plurality of vertical positions and are horizontally shifted with respect to the horizontal readout areas (13, 17a, 17b, 17c) of the vertical positions of the second part of the plurality of vertical positions.

11. Vehicle (1) with a lidar sensor system (2) according to one of the preceding claims.

12. Vehicle (1) according to claim 1, wherein different vertical positions on the detector array (7) correspond to different rows of the detector array (7); and 2023PF01547 21 different horizontal positions on the detector array (7) correspond to different columns of the detector array (7) the lidar sensor system (2) is mounted on the vehicle (1) such that the columns of the detector array (7) are oriented perpendicular to a vertical axis of the vehicle (1).

13. Method for operating a lidar sensor system (2) for a vehicle (1), wherein light is emitted into the environment of the lidar sensor system (2) by means of a transmitter device (6) of the lidar sensor system (2); a light deflection device (8) of the lidar sensor system (2) is successively moved into a plurality of different positions, wherein, depending on the position in the environment, reflected components of the emitted light are directed at different horizontal angles of incidence onto a detector array (7) of the lidar sensor system (2); different vertical positions on the detector array (7) correspond to different vertical angles of incidence of the reflected components; for a plurality of vertical positions on the detector array (7), a corresponding horizontal readout area (13, 17a, 17b, 17c) is specified on the detector array (7);For each vertical position of the plurality of vertical positions for a current position of the light deflection device (8), those optical detectors are read out which lie in the horizontal readout area (13, 17a, 17b, 17c) of the respective vertical position, and depending on this, an intensity value is determined for the horizontal angle of incidence corresponding to the current position and the vertical angle of incidence corresponding to the respective vertical position; for each plurality of vertical positions, a horizontal reference position (14) is specified on the detector array (7) at which a maximum incident light intensity is expected; for a first part of the plurality of vertical positions corresponding to a first vertical area of ​​the detector array (7), the respective horizontal readout area (13, 17a, 17b, 17c) contains the respective horizontal reference position (14);and for a second part of the plurality of vertical positions corresponding to a second vertical area of ​​the detector array (7) the respective horizontal; 2023PF01547 22 The selection area (13, 17a, 17b, 17c) does not include the respective horizontal reference position (14).

14. Method according to claim 13, wherein for each vertical position of the plurality of vertical positions for each of the plurality of positions of the light deflection device (8) those optical detectors are read out which lie in the horizontal readout area (13, 17a, 17b, 17c) of the respective vertical position, and depending thereon an intensity value is determined for the horizontal angle of incidence corresponding to the respective position and the vertical angle of incidence corresponding to the respective vertical position.

15. Method according to one of claims 13 or 14, wherein the horizontal reference positions (14) for the plurality of vertical positions are determined depending on a spatial arrangement of the detector array (7) and the transmitting device (6) relative to each other.

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