All-round LiDAR and vehicle

Abstract

The invention relates to a omnidirectional LiDAR (1) comprising at least one emitter for emitting a laser beam (2), a receiver for detecting scattered laser light, and a reflective surface (3) arranged in the beam path of the laser beam (2) during operation, wherein the laser beam (2) can be projected into the environment with a horizontal scanning angle of 360° about a vertical axis (4) by a relative movement between the emitter and the reflective surface (3), and wherein the emitter and the receiver are integrated into a common emitter-receiver arrangement (5). The omnidirectional LiDAR according to the invention is characterized in that the emitter-receiver arrangement (5) is arranged on a rotating arm (7) extending radially outwards from the vertical axis (4) in a plane of rotation (6), wherein the rotating arm (7) is rotatable about the vertical axis (4) by means of an actuator (8). a mirror arrangement (9) encompassing the reflective surface (3) and arranged coaxially to the vertical axis (4) with an axial distance (a) to the plane of rotation (6) that is fixed during operation; and the mirror arrangement (9) is rigidly connected to a support rod (10) running on the vertical axis (4), wherein the rotation arm (7) is rotatably mounted relative to the support rod (10).

Description

[0001] The invention relates to a surround-view LiDAR of the type defined in more detail in the preamble of claim 1 and to a vehicle with such a surround-view LiDAR.

[0002] The use of LiDAR sensors on vehicles for environmental monitoring has proven effective. A LiDAR sensor emits light, typically laser light, into the surroundings, which is scattered by objects in the environment. This scattered light is then detected by a detector. The distance of the object to the LiDAR sensor can be calculated based on the time-of-flight difference. A corresponding laser beam is typically moved through the environment in a line, a process also known as scanning. The beam can also be moved perpendicular to the main scanning direction to scan the environment not just along a line, but across an area. Thus, a LiDAR sensor captures the environment with a vertical and horizontal field of view. Line-like scanning can also be performed on multiple planes. The result of this scanning process is a point cloud.Taking into account the known installation position of the LiDAR sensor on the vehicle, it is then possible to locate corresponding environmental objects relative to the vehicle.

[0003] Several LiDAR sensor designs are known. One type involves relatively compact sensors that can be discreetly integrated into the vehicle's appearance, but have a comparatively small detection range. Such LiDAR sensors are usually integrated into the radiator grille, bumper, or similar components. However, LiDAR sensors that provide a 360-degree view around the vehicle are used, particularly for test vehicles in the development of automated and autonomous driving. Such a LiDAR sensor is designed as a kind of tower and mounted more or less centrally on the vehicle's roof. This type of LiDAR sensor emits its laser beam into the surrounding area, scanning it like a lighthouse.As mentioned above, the laser beam can not only be moved 360° around the vehicle's vertical axis, but it can also be moved vertically to create a scan line, or multiple scanning lasers can be used. This provides a particularly large detection field.

[0004] However, such LiDAR sensors, described in the application as omnidirectional LiDAR, have several disadvantages. To capture the largest possible range, it is advantageous for the LiDAR sensor to be mounted at a high point above the vehicle. To move the laser beam, it is typically directed into different regions of the surrounding area by a movable mirror. The actuator for moving the mirror is integrated into the LiDAR sensor. This results in a comparatively large component being located at a considerable distance from the mounting point of the LiDAR sensor on the vehicle. This necessitates a robust bracket to support the LiDAR sensor. Consequently, the overall mass of the vehicle increases, and the LiDAR sensor itself is relatively large. This increases the vehicle's frontal area, which negatively impacts air resistance.Furthermore, the wiring harness for power supply and data communication must be routed from the vehicle interior to the laser emitters and detectors, as well as to the actuator, via the aforementioned bracket. Due to their robust design, such all-around LiDARe systems are difficult to integrate into the vehicle's body design. While this is of minor importance for prototype vehicles, vehicle design is crucial for production vehicles.

[0005] German patent application DE 10 2022 206 076 A1 discloses a LiDAR device for a vehicle and a method for optically capturing a vehicle's field of view. The document describes a LiDAR sensor in which a rotatable polygon mirror is arranged in the light beam path between an emitter and a receiver of the LiDAR. The light emitted into the environment and the light scattered towards the receiver are reflected by different mirror surfaces of the polygon mirror. The LiDAR sensor disclosed in the document allows for a flat design. Furthermore, the LiDAR sensor can include multiple emitters for emitting laser light. The separate arrangement of the emitter and receiver improves heat dissipation, which allows for increased detection performance. Due to the separate optical paths for transmitting and receiving laser light, there is less interference, which further improves detection accuracy.

[0006] Another LiDAR sensor is known from DE 10 2019 218 005 A1. An optical transmitter and an optical receiver of the LiDAR sensor are arranged on the same side with respect to a scan unit. The scan unit comprises a rotatable mirror that can have two different mirrored surfaces. The mirror can be rotated to guide the laser beam projected into the environment by the LiDAR sensor. The design disclosed in the publication allows for a particularly compact construction while simultaneously providing a large horizontal field of view. The maximum detection range can be achieved almost independently of the scanned solid angle.

[0007] Furthermore, CN 111381219 A discloses a laser-emitting and receiving assembly, a laser radar, and a scanning system and method for the laser radar. The laser emitter-receiver assembly moves in a concentric circular path around a vertical axis and is directed towards a mirror arranged axially spaced from the laser emitter-receiver assembly along the vertical axis. The mirror is inclined relative to the vertical axis so that the laser beams are reflected radially away from the vertical axis. Several optical lenses are arranged between the laser emitter-receiver assembly and the mirror.

[0008] Furthermore, WO 2023 / 048691 A1 discloses a fast and high-resolution LiDAR with a multi-axis and multi-surface polygon scanner. A laser emitter-receiver array is directed at a rod which carries several stacked ring-shaped faceted mirrors. The rod can be rotated and moved translationally in the axial direction.

[0009] Furthermore, DE 199 54 362 A1 discloses a car radar for detecting lane markings and obstacles ahead. The car radar uses a light source that emits a beam to scan the surroundings. The car radar comprises a first scanning mechanism for detecting a first scanning area and a second scanning mechanism for detecting a second scanning area. The car radar includes an annular faceted mirror.

[0010] Furthermore, DE 10 2014 005 350 A1 discloses an optical obstacle detection sensor for a vehicle. A light source and an annular mirror are arranged at a distance from each other on a housing, with the light source directed at the mirror to generate a measuring beam that can be projected into the surroundings. The point of incidence of the measuring beam on the mirror is adjustable. The housing can be extended translationally relative to a mounting frame.

[0011] The present invention is based on the objective of providing an improved all-round LiDAR for vehicles.

[0012] This problem is solved according to the invention by a surround-view LiDAR with the features of claim 1. Advantageous embodiments and further developments, as well as a vehicle with such a surround-view LiDAR, are described in the dependent claims.

[0013] A generic omnidirectional LiDAR comprising at least one emitter for emitting a laser beam, a receiver for detecting scattered laser light, and a reflective surface arranged in the beam path of the laser beam during operation, wherein the laser beam can be projected into the environment by a relative movement between the emitter and the reflective surface with a horizontal scanning angle of 360° about a vertical axis, and wherein the emitter and the receiver are integrated into a common emitter-receiver arrangement, wherein the emitter-receiver arrangement is arranged on a rotating arm extending radially outwards from the vertical axis in a plane of rotation, wherein the rotating arm is rotatable about the vertical axis by means of an actuator; a mirror arrangement comprising the reflective surface and arranged coaxially to the vertical axis with an axial distance to the plane of rotation that is fixed during operation; wherein according to the invention the mirror arrangement is rigidly connected to a support rod extending on the vertical axis, wherein the rotating arm is rotatably mounted relative to the support rod, and wherein the mirror arrangement is divided in the axial direction into two or more mirror ring segments extending around the entire circumference of the mirror arrangement, wherein each mirror ring segment is inclined with an individual tilt angle relative to the vertical axis in a plane spanned by the axial direction and a radial direction perpendicular to the axial direction, and wherein for each mirror ring segment at least one emitter-receiver arrangement directed towards the respective mirror ring segment is provided on the rotating arm.

[0014] In contrast to known omnidirectional LiDARs, the omnidirectional LiDAR according to the invention is characterized by the fact that the mirror assembly is rigidly mounted and the emitter-receiver assembly moves around the mirror assembly. In contrast, prior art solutions use a rigid emitter-receiver assembly and a movable mirror. This allows all complex, heavy, and movable components to be relocated from the head or turret of the omnidirectional LiDAR to its base. Consequently, all components that will be spaced away from the vehicle during operation can be designed to be simple, compact, and lightweight, resulting in a comparatively small and lightweight support structure for the mirror assembly. This simplifies the design of the omnidirectional LiDAR and reduces the frontal area oriented in the direction of travel.The all-around LiDAR according to the invention can thus be designed to be compact and lightweight, which has a positive effect on the vehicle's drag coefficient and therefore on fuel consumption. Furthermore, the weight can be reduced, which also has a beneficial effect on the vehicle's fuel consumption. Positioning the aforementioned components at the base of the support rod not only facilitates a simple design but also an advantageous center of gravity.

[0015] The mirror assembly can be designed to be particularly compact, for example, with a volume of approximately 50 x 20 mm. The weight of the mirror assembly is on the order of a few grams. The frontal area can be reduced by up to 90%. The support rod can be made correspondingly narrower, thus resembling an antenna. This allows the all-around LiDAR according to the invention to integrate more seamlessly into the vehicle's visual appearance. The design is improved, which increases the acceptance of using a vehicle incorporating the all-around LiDAR according to the invention. Since the mirror assembly is a passive component, there is no need to route a wiring harness inside or outside the support rod. Therefore, the support rod can also be made transparent, for example, from glass, polymethyl methacrylate, or similar materials.The all-round LiDAR according to the invention is therefore particularly suitable for integration into production vehicles and not only into test vehicles.

[0016] By using mirror ring segments inclined at different angles relative to the surroundings and by providing an individual emitter-receiver arrangement for each mirror ring segment, different vertical sections of the environment can be captured simultaneously. This makes it possible to capture the environment with a vertical detection or scanning angle. The detection range of the omnidirectional LiDAR can thus be increased by providing a vertical field of view.

[0017] The individual mirror ring segments can be designed as truncated cones. This means that the mirror ring segments can be rotationally symmetrical about the vertical axis. Manufacturing such truncated cone-shaped mirror ring segments is comparatively complex; however, no special measures are required for evaluating the scattered laser light registered by the receiver in a subsequent control and evaluation routine.

[0018] To enable the largest possible vertical detection angle, three or more mirror ring segments are preferably provided. More than one individual emitter-receiver arrangement can also be assigned to the same mirror ring segment to allow for a higher scanning resolution.

[0019] Preferably, at least two emitter-receiver assemblies are arranged on the rotating arm at different radial distances. This simplifies the integration of the emitter-receiver assemblies on the rotating arm, as a larger area can be used for their arrangement. By tilting the emitter-receiver assemblies to varying degrees, i.e., aligning them with the mirror arrangement, the laser light can be directed into different regions of space. Preferably, all emitter-receiver assemblies on the rotating arm are arranged at the same position in the circumferential direction, i.e., aligned radially. However, it is also conceivable that the rotating arm can have any horizontal extent in the plane of rotation in the circumferential direction. In this case, individual emitter-receiver assemblies could also be offset from each other in the circumferential direction.

[0020] Particularly preferred are at least two emitter-receiver arrangements with different radial spacings aligned on the same mirror ring segment. Due to the different radial spacings on the rotating arm, it is thus possible to project laser beams for scanning the environment into different regions of space, despite being projected onto the same mirror ring segment. This makes it possible to easily achieve different vertical emission angles for the laser light.

[0021] According to a further advantageous embodiment of the circumferential LiDAR according to the invention, the mirror arrangement is further divided in the circumferential direction into at least three mirror facets, wherein the mirror facets are designed as flat mirror surfaces. This simplifies the manufacturing of the mirror arrangement, since no curved mirror surfaces need to be produced. However, the mirror arrangement preferably comprises more than three mirror facets, which facilitates the guidance of the laser beam in the circumferential direction along the surroundings. If the mirror arrangement is axially divided into several mirror ring segments, each of these mirror ring segments can have corresponding mirror facets or be formed by mirror facets. The individual mirror facets of the mirror ring segments can be arranged at the same circumferential position when viewed in the circumferential direction or can be offset from one another.

[0022] If the mirror arrangement, or rather the mirror ring segments, include corresponding mirror facets, the laser beam is projected into different regions of the surrounding area when passing over a particular mirror facet than when passing over a conical mirror. This also means that, viewed circumferentially, the same surrounding area is scanned again when the laser beam jumps from one mirror facet to the adjacent one. Furthermore, undesirable scattering effects can occur at the mirror facet boundaries. This must be taken into account when controlling the omnidirectional LiDAR and evaluating the sensor data generated by the receivers. In particular, sensor data generated in the immediate vicinity of the mirror facets is ignored.No evaluation is performed directly at the aforementioned mirror edges between the mirror facets to prevent interference from undefined light refractions. This has no negative impact on the horizontal resolution, as the reflections of adjacent mirror facets intersect after a short distance, ensuring a seamless scan of the surroundings.

[0023] The relationship between the circumferential angle of the rotating arm and the horizontally viewed exit angle of the laser beam can be unambiguously defined and stored in a suitable control unit, for example, in the form of a lookup table. The horizontal exit angle of the laser beam is thus a function of the circumferential angle of the rotating arm, even when a mirror arrangement with faceted mirrors is used.

[0024] A further advantageous embodiment of the omnidirectional LiDAR according to the invention provides for at least three mirror ring segments and at least 16 mirror facets per mirror ring segment. This has proven to be a particularly favorable embodiment for the omnidirectional LiDAR according to the invention during development. The design of the mirror arrangement is thus not overly complex, yet allows for sufficiently fine scanning of the surroundings.

[0025] According to a further advantageous embodiment of the omnidirectional LiDAR according to the invention, the support rod is designed as a telescopic rod, and in particular, an actuator is provided for extending and retracting the support rod. As already mentioned, it is not necessary to route power supply cables, data cables, or mechanical components through or along the support rod. Thus, the support rod can simply be designed as a telescopic rod. This allows the support rod to be extended and retracted as needed. For example, the support rod can be retracted when the vehicle is parked or when visiting a car wash. This prevents damage to the omnidirectional LiDAR, for example, from the ceiling of an underground parking garage or the washing process in a car wash. The support rod can be extended and retracted manually. However, for increased convenience, the support rod can also be extended and retracted using a dedicated actuator.

[0026] A further advantageous embodiment of the omnidirectional LiDAR according to the invention provides a housing ring extending coaxially to the vertical axis in the plane of rotation, wherein the rotating arm is supported at its outer end on the housing ring, and wherein at least one radially extending support web connecting the housing ring to the support rod is provided. By providing the housing ring, the rotating arm can be supported at its outer end when viewed radially, which improves its smooth operation. In addition, an external housing is provided, which facilitates the integration of the omnidirectional LiDAR into a suitable vehicle. Thus, a recess geometrically adapted to the shape of the housing ring can be provided in the vehicle's outer skin, into which the housing ring is inserted.

[0027] Preferably, the housing ring is provided with a cover, transparent to laser light and parallel to the plane of rotation, across its opening facing the mirror assembly. This cover protects the sensitive components of the omnidirectional LiDAR, such as the rotating arm, the actuator for moving the rotating arm, the emitter-receiver assemblies, and power supply and data lines, from environmental influences. This prevents dirt, rain, snow, hail, moisture, and similar elements from penetrating the space enclosed by the housing ring. Because the cover is transparent to laser light, the emitters are still able to project the laser light onto the mirror assembly, allowing the receivers to detect the scattered laser light reflected by the mirrors.

[0028] A further advantageous embodiment of the omnidirectional LiDAR according to the invention provides that the mirror assembly is hermetically sealed off from the environment by a protective cap that is transparent to laser light. This protects not only the components located at the base of the support rod from environmental influences, but also the mirror assembly itself. In particular, the protective cap and the cover for the housing ring can be made at least partially of the same material or comprise it.

[0029] According to the invention, a vehicle comprises a surround-view LiDAR as described above. The vehicle can be any road vehicle such as a car, truck, van, bus, or the like. Generally, it is also conceivable that it could be a rail vehicle, watercraft, or aircraft. With the aid of the surround-view LiDAR according to the invention, sensor data is generated, in particular, from which control commands for the vehicle are derived. In particular, the vehicle can be controlled at least partially automatically or even autonomously.

[0030] The vehicle further comprises a computing unit, for example, a control unit, a central on-board computer, or the like, for controlling the omnidirectional LiDAR and processing the sensor data generated by the omnidirectional LiDAR. A program executed on the computing unit takes into account the specific characteristics of the omnidirectional LiDAR according to the invention. To map a reflection point in the coordinate system of the point cloud, the vertical emission angle of the laser light is first determined. This emission angle depends in particular on the emitter-receiver arrangement used and the mirror ring segment illuminated by the emitter-receiver arrangement. For example, the vertical emission angle can be stored in a corresponding lookup table. The vertical emission angle is independent of the circumferential position of the rotating arm for each emitter-receiver arrangement.To determine the horizontal exit angle, the current circumferential angle of the rotating arm is recorded. Based on the circumferential angle, the horizontal exit angle can be deduced. If the mirror arrangement or the relevant mirror ring segment is conical, the horizontal exit angle corresponds to the circumferential angle of the rotating arm. However, if the laser beam is projected onto a mirror facet, the orientation of the corresponding planar mirror facet relative to its surroundings must also be considered. Depending on the circumferential angle of the rotating arm, it is possible to determine which mirror facet is currently being illuminated. For each mirror facet, a corresponding lookup table contains a mapping indicating which circumferential angle of the rotating arm corresponds to which horizontal exit angle. A further lookup table contains the distance of the mirror facet from the vertical axis.Using this distance, the measured path length of the laser beam, and the vertical and horizontal exit angles, the reflection point relative to the vertical axis and thus to the vehicle coordinate system can be determined. The inventive all-around LiDAR is therefore operated by a corresponding inventive method based on such control software.

[0031] An advantageous embodiment of the vehicle according to the invention provides that the plane of rotation is embedded in an opening in the vehicle's outer skin, particularly in the vehicle roof. This allows for a quick, simple, and reliable arrangement of the all-around LiDAR. Especially when the all-around LiDAR is mounted on the vehicle roof, reliable scanning of the surroundings is possible. The vertical axis of the all-around LiDAR is preferably aligned parallel to the vehicle's vertical axis; in particular, the vertical axis and the vehicle's vertical axis are coaxial to each other.

[0032] Further advantageous embodiments of the all-round LiDAR according to the invention and of the vehicle according to the invention also result from the exemplary embodiments, which are described in more detail below with reference to the figures.

[0033] This shows: Fig. 1 a schematic front view of a known vehicle and a vehicle according to the invention, each comprising a round-the-round LiDAR; Fig. 2 a perspective view of a 360° LiDAR according to the invention; Fig. 3 a schematic top view of the all-round LiDAR according to the invention; Fig. 4 a schematic top view of an alternative embodiment of the all-round LiDAR according to the invention; Fig. 5 a schematic top view of a further alternative embodiment of the all-round LiDAR according to the invention; Fig. 6 a schematic side view of the all-round LiDAR according to the invention; Fig. 7 a detailed view of the in Fig. 6 details shown A; Fig. 8 a schematic detail view of a mirror arrangement encompassed by the all-round LiDAR according to a first embodiment; Fig. 9 a schematic representation of the beam path of the laser light emitted by the omnidirectional LiDAR according to the invention; Fig. 10 a detailed view of the in Fig. 9 shown details B; and Fig. 11 A schematic top view of the beam path of the laser light for a mirror arrangement comprising mirror facets in two different states.

[0034] Fig. Figure 1 shows in subfigure a) the front view of a generic vehicle with a known all-round LiDAR mounted on the roof. Subfigure b) shows, in contrast, the front view of a vehicle 17 according to the invention, which includes an all-round LiDAR 1 according to the invention. The all-round LiDAR 1 is also mounted on the vehicle roof.

[0035] How Fig. As shown in Figure 1 a), the generic all-around LiDAR is much larger than the all-around LiDAR 1 according to the invention, resulting in a correspondingly large frontal area. This has a detrimental effect on the vehicle's drag coefficient. Furthermore, in known all-around LiDARs, a wide variety of components such as emitters, receivers, mirrors, actuators, cables, and the like are integrated into a head 19 of the corresponding LiDAR tower, located away from the base 18. This necessitates a rigid and therefore massive design for the LiDAR tower. According to the invention, however, only a passive mirror arrangement 9 is arranged in the area of ​​the head 19, which can be made comparatively compact and lightweight. Consequently, the support rod 10 carrying the mirror arrangement 9 can also be designed to be compact. The all-around LiDAR 1 according to the invention thus resembles an antenna and therefore blends harmoniously into the visual appearance of the vehicle 17.

[0036] Fig. Figure 2 shows a perspective view of the omnidirectional LiDAR 1 according to the invention. The support rod 10 extends along a vertical axis 4. The geometric relationships are best described using a cylindrical coordinate system, having an axial direction Ax, a radial direction R, and a circumferential direction U. According to the invention, an emitter-receiver arrangement 5, comprising an emitter for emitting a laser beam and a receiver for detecting scattered laser light, is arranged on a rotating arm 7 extending radially outward from the vertical axis 4 in a plane of rotation 6. Ten emitter-receiver arrangements 5 are shown here. The rotating arm 7 can be rotated about the vertical axis 4 or the support rod 10 by means of an actuator 8. For example, the actuator 8 can be an electric motor. The actuator 8 can be controlled in a targeted manner to project the laser light into the environment according to instructions stored in a control routine.Laser light emitted by the emitter-receiver arrangement 5 is directed via a [missing information] in . Fig. The reflection is directed into the surroundings by the reflective surface 3 shown in detail in section 8. The reflective surface 3 is part of a mirror arrangement 9 that is coaxial to the vertical axis 4 at a distance a that is fixed during operation, see [reference]. Fig. 6, is arranged in relation to the plane of rotation 6.

[0037] Preferably, the support rod 10 can be designed as a telescopic rod, so that when the omnidirectional LiDAR 1 is not in operation, the mirror assembly 9 can be retracted in the direction of the plane of rotation 6. The mirror assembly 9 is rigidly connected to the support rod 10, with the rotating arm 7 being rotatably mounted relative to the support rod 10. According to the invention, the respective emitters and receivers are thus moved around rigidly arranged mirrors, in contrast to solutions known from the prior art. This is the fundamental prerequisite for providing a mirror assembly 9 designed as a passive component in the area of ​​the head 19, which is what enables the compact and lightweight design of the omnidirectional LiDAR 1 according to the invention. The sensitive electrical and electronic components, as well as the movable components, are located at the base 18 and can be mounted, in particular, on the vehicle 17.

[0038] Advantageously, a housing ring 13 is provided which supports the support rod 10 via at least one radially extending support web 14. The rotating arm 7 can rest on the housing ring 13 at its free end as viewed in the radial direction R, which improves smooth running. The rotating arm 7 can slide on the housing ring 13 or roll along it by providing suitable rolling elements. Magnetic bearings are also a possibility.

[0039] A cover 15, shown here as transparent, is particularly preferred and is provided at an opening in the housing ring 13 facing the mirror arrangement 9. The cover 15 is transparent to the laser light used. The rotating arm 7, the emitter-receiver arrangements 5, the actuator 8, and the power and data lines (not shown in detail) can be protected from environmental influences.

[0040] Furthermore, the mirror arrangement 9 can also be protected from environmental influences by a protective cap 16. Here too, the protective cap 16 is made of, or encloses, a material transparent to laser light.

[0041] Fig. Figure 3 shows a top view of the all-round LiDAR 1 according to the invention. In the Fig. In the embodiment shown in Figure 3, the rotating arm 7 is rod-shaped.

[0042] As the Fig. 4 and Fig. As shown in Figure 5, the rotating arm 7 can also be disk-shaped. Particularly preferred are several emitter-receiver arrangements 5 distributed along the rotating arm 7 in the radial direction R. As Fig. 3 and Fig. As shown in Figure 5, these emitter-receiver arrangements can advantageously be arranged at the same circumferential position, i.e., lying on a line when viewed in the radial direction R.

[0043] How Fig. As shown in Figure 4, it is also conceivable that one or more emitter-receiver arrangements 5 may be offset from each other in the circumferential direction U. The embodiments can be combined with each other as desired.

[0044] Fig. Figure 6 shows a schematic side view or sectional view of the all-around LiDAR 1 according to the invention. Detail A is highlighted. Detail A is shown in an enlarged view in Figure 6. Fig. 7 shown. Fig. Figure 7 illustrates the geometry of a possible embodiment of the mirror arrangement 9. The protective cap 16 is also visible.

[0045] The possible embodiments of the mirror arrangement 9 are described based on the Fig. 7 and Fig. 8 described. Fig. Figure 8 shows a perspective view of the mirror arrangement 9 from below. The mirror arrangement 9 can be designed as a truncated cone. Thus, the reflection surface 3 is curved and ring-shaped. According to the invention, the mirror arrangement 9 is divided in the axial direction Ax into several mirror ring segments 11, for example, three mirror ring segments 11, as shown. These mirror ring segments 11 can also be designed as truncated cones, and thus be rotationally symmetrical. In this case, each mirror ring segment 11 represents its own reflection surface 3.

[0046] According to an advantageous embodiment, the mirror arrangement 9, in particular a mirror arrangement 9 subdivided into mirror ring segments 11, is further subdivided in the circumferential direction U into several mirror facets 12. Mirror facets 12 are formed by planar mirror surfaces. Each mirror facet 12 forms a reflective surface 3. The use of mirror facets 12 allows for simple and cost-effective manufacturing of the mirror arrangement 9, although some special considerations must be taken into account in the control of the omnidirectional LiDAR 1 and the processing of the correspondingly generated sensor data. The mirror facets 12 provided on different mirror ring segments 11 are inclined relative to the vertical axis 4. All mirror facets 12 of the same mirror ring segment 11 have the same tilt angle relative to the vertical axis 4 in a plane defined by the axial direction Ax and the radial direction R.In such an embodiment, the mirror arrangement 9 can be referred to as a faceted mirror.

[0047] This allows the in Fig. Figure 9 shows the light beam path of the laser beams 2 emitted and received by the emitter-receiver assemblies 5. It is particularly advantageous to have several emitter-receiver assemblies 5 arranged at different radial positions on the rotating arm 7 and aligned with the same mirror ring segment 11. This makes it possible to provide an enlarged vertical detection range for the omnidirectional LiDAR 1, as shown.

[0048] At the in Fig. In the embodiment shown in Figure 9, the vertical field of view is 40° at a resolution of 5° using three mirror ring segments 11 with inclinations of 35°, 45° and 55° respectively. Ten emitter-receiver arrangements 5 are distributed along the rotating arm 7. Each mirror ring segment 11 has 16 mirror facets 12 viewed in the circumferential direction U.

[0049] Fig. 10 shows the in Fig. 9 Detail B shown in an enlarged view.

[0050] In the simplest case, which is not covered by the scope of protection, the mirror arrangement 9 thus comprises a single mirror ring segment 11, which is shaped as a conical ring or truncated cone. According to the invention, however, the mirror arrangement 9, viewed in the axial direction Ax, comprises two or more mirror ring segments 11, each inclined to a different degree relative to the vertical axis 4. In this case, the mirror arrangement 9 is continuously curved in the circumferential direction U, such that the circumferential angle at which the rotation arm 7 is located also corresponds to the horizontal exit angle of the laser light.

[0051] If, however, the mirror arrangement 9 includes mirror facets 12, then there are no curvatures whatsoever. This leads to the result shown in Fig. 11. The facts shown.

[0052] In Fig. Figure 11 shows the path of the light rays when passing over the same mirror facet 12 at two different times. This shows Fig. 11a) a position of the rotating arm 7 in which the laser beam 2, viewed in the circumferential direction U, is located at the beginning of the mirror facet 12. In Fig. 11b) the rotation arm 7 has moved further, so that the laser beam 2 is located in the center of the mirror facet 12 when viewed in the circumferential direction U. Fig. Figure 11 illustrates the relationship between the circumferential position of the rotating arm 7, the irradiated mirror facet 12 and the resulting horizontal exit angle of the laser beam 2.

[0053] An inventive method for operating the omnidirectional LiDAR 1 takes this into account by providing a lookup table in which the respective circumferential positions for the rotating arm 7 and the resulting horizontal exit angles, taking into account the orientation of the mirror facets 12, are stored. Vertical exit angles can be stored in the same or a separate lookup table. It is particularly preferred that the sampling rate of the inventive omnidirectional LiDAR 1 is adjusted to the circumferential angle in such a way as to ensure that no evaluation is carried out directly at the mirror edges 20 between two mirror facets 12 adjacent to each other in the circumferential direction U, in order to prevent interference effects caused by undefined light refractions.

[0054] The inventive method for operating the all-round LiDAR 1 can comprise the following process steps: 1. Emitting laser beams 2; 2. Receiving reflected or scattered laser light; 3. Determining the time interval between the emission and reception of the laser light; 4. Normalization of the time duration by correcting the individual travel distances from the emitter to the mirror arrangement 9 and the distance of the mirror surfaces to the vertical axis 4; 5. Mapping of the reflection points in the coordinate system of the point cloud.

[0055] The omnidirectional LiDAR 1 according to the invention is characterized by a reduced frontal area. Its performance compared to known omnidirectional LiDARs is maintained.

[0056] In particular, the same range, as well as vertical and horizontal resolution and sampling rate, are ensured. The vehicle design of a vehicle 17 incorporating the all-around LiDAR 1 is less drastically affected. Likewise, the shadowing caused by the LiDAR sensor is reduced, which has a beneficial effect on the quality of the environmental perception of other vehicles equipped with LiDAR sensors.

[0057] In addition to the optimized drag coefficient, the smaller frontal area also results in less and quieter wind noise. The weight savings also allow for a reduction in the vehicle's overall weight, thereby achieving efficiency gains. This enables a greater range. Furthermore, the inventive all-around LiDAR 1 can be manufactured more cost-effectively due to the reduced number of parts and materials. Complex and expensive components can be arranged inside the vehicle and thus better protected against damage. The usable roof area is increased by the narrower mounting, which still allows for the transport of roof-mounted accessories such as a roof box. The support rod 10 can also be retracted for low clearances or when using a car wash.

Claims

[1] A surround-view LiDAR (1) comprising at least one emitter for emitting a laser beam (2), a receiver for detecting scattered laser light and a reflective surface (3) arranged in the beam path of the laser beam (2) during operation, wherein the laser beam (2) can be projected into the environment by a relative movement between the emitter and the reflective surface (3) with a horizontal scanning angle of 360° about a vertical axis (4), and wherein the emitter and the receiver are integrated into a common emitter-receiver arrangement (5), wherein the emitter-receiver arrangement (5) is arranged on a rotating arm (7) extending radially outwards from the vertical axis (4) in a plane of rotation (6), wherein the rotating arm (7) is rotatable about the vertical axis (4) by means of an actuator (8); a mirror arrangement (9) encompassing the reflective surface (3) and arranged coaxially to the vertical axis (4) with an axial distance (a) to the plane of rotation (6) that is fixed during operation, characterized by , that the mirror arrangement (9) is rigidly connected to a support rod (10) extending on the vertical axis (4), wherein the rotation arm (7) is rotatably mounted relative to the support rod (10), and wherein the mirror arrangement (9) is divided in the axial direction (Ax) into two or more mirror ring segments (11) extending around the entire circumference of the mirror arrangement (9), each mirror ring segment (11) being inclined with an individual tilt angle relative to the vertical axis (4) in a plane spanned by the axial direction (Ax) and a radial direction (R) perpendicular to the axial direction (Ax), and wherein for each mirror ring segment (11) at least one emitter-receiver arrangement (5) directed towards the respective mirror ring segment (11) is provided on the rotating arm (7). [2] Surround-view LiDAR (1) according to claim 1, characterized by , that at least two emitter-receiver arrangements (5) are arranged at different radial distances on the rotating arm (7). [3] Surround-view LiDAR (1) according to claim 1 and 2, characterized by, that at least two emitter-receiver arrangements (5) having different radial spacings are aligned on the same mirror ring segment (11). [4] Surround-view LiDAR (1) according to any one of claims 1 to 3, characterized by , that the mirror arrangement (9) is subdivided in the circumferential direction (U) into at least three mirror facets (12), wherein mirror facets (12) are designed as planar mirror surfaces. [5] Surround-view LiDAR (1) according to any one of claims 1 to 4, characterized by , that the support rod (10) is designed as a telescopic rod, in particular an actuator is provided for extending and retracting the support rod (10). [6] Surround-view LiDAR (1) according to any one of claims 1 to 5, characterized by, that a housing ring (13) extending coaxially to the vertical axis (4) in the plane of rotation (6) is present, wherein the rotation arm (7) is supported on the housing ring (13) at its outer end, and wherein at least one support web (14) extending in the radial direction (R) connecting the housing ring (13) to the support rod (10) is present. [7] Surround-view LiDAR (1) according to claim 6, characterized by , that the housing ring (13) is provided with a cover (15) that is transparent to the laser light and parallel to the plane of rotation (6) over its entire surface at its opening facing the mirror arrangement (9). [8] Surround-view LiDAR (1) according to any one of claims 1 to 7, characterized by , that the mirror arrangement (9) is hermetically sealed off from the environment by a protective cap (16) that is transparent to the laser light. [9] Vehicle (17), characterized by a surround-view LiDAR (1) according to any one of claims 1 to 8.

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