DE102016201057A1 - LIDAR DEVICE, VEHICLE AND METHOD FOR DETECTING AN OBJECT - Google Patents

Abstract

The invention relates to a lidar device (100) for detecting an object, having an optical device (6) which can be rotated around a rotation axis (14) and which has a plurality of first optical elements (12) and a multiplicity of second optical elements (11) ; a transmitting device (10) for emitting laser light beams; and a receiving device (9) for receiving reflected laser light beams; wherein the optical device (6) is designed such that upon rotation of the optical device (6) about the axis of rotation (14) laser light beams by means of the transmitting device (10) by a respective optical element (12) of the plurality of first optical elements (12) are transmitted, and the laser light beams reflected on the object are received by the receiving means (9) after passing through an optical element (11) of the plurality of second optical elements (11).

Description

The invention relates to a lidar device for detecting an object, a vehicle and a method for detecting an object.

Lidar (light detection and ranging) systems have laser diodes that emit laser pulses. The laser pulses reflected on objects are detected by receivers of the Lidar system and the recorded data is evaluated. Lidar systems can be used, for example, for distance measurement, speed control or obstacle detection.

Particularly in driver assistance systems, lidar systems are used to detect other vehicles or road boundaries and can thus enable semi-autonomous or autonomous driving.

The emitted laser beam has to be deflected accordingly in order to be able to scan a desired surrounding area around the vehicle. For scanning, for example, mirrors or prisms can be used, which are rotated or deflected in corresponding directions.

From the EP 2 657 686 A1 For example, a device for detecting scattered light is known, wherein light is deflected by a rotatably mounted prism, whereby the detection range of the lidar system can be adjusted.

Often, however, it is desirable to divert the laser light differently for different detection areas or to optically break. For example, it may be advantageous to scan a surrounding region located centrally in front of a vehicle within a large distance range with laser beams with small opening angles, while lateral areas of the vehicle are to be scanned in a smaller distance range with a correspondingly larger opening angle.

It is therefore an object of the present invention to enable a more accurate and more adjustable detection of objects.

This object is achieved by a lidar device for detecting an object with the features of claim 1, a vehicle having the features of claim 12, and a method for detecting an object having the features of claim 13.

Accordingly, the present invention provides a lidar apparatus for detecting an object having an optical device rotatable about an axis of rotation and having a plurality of first optical elements and a plurality of second optical elements. The lidar device further comprises a transmitting device for emitting laser light beams, and a receiving device for receiving reflected laser light beams, wherein the optical device is designed such that upon rotation of the optical device about the axis of rotation laser light beams by means of the transmitting device by one optical element of the plurality of first can be transmitted through optical elements, and the laser light beam reflected on the object can be received by the receiving device after passing through an optical element of the plurality of second optical elements.

The invention accordingly further provides a vehicle with a lidar device.

Finally, the invention provides a method for detecting an object. In this case, laser light beams are emitted by means of a transmitting device through a first optical element of a multiplicity of first optical elements of an optical device which is rotatable about an axis of rotation. The laser light beams reflected on the object are received by a receiving means after passing through an optical element of a plurality of second optical elements of the optical device.

By rotating the optical device, laser light beams can be emitted successively through the first optical elements. By suitable choice and alignment of the optical elements, an arbitrary detection area can thus be scanned through the lidar device. In this case, alignment is in particular the orientation of the optical elements with respect to the light path of the emitted laser light beam. In particular, different areas with different optical elements can be scanned and thus the accuracy of the lidar device can be optimized. Particularly preferred areas can be scanned, for example, by a larger number of optical elements with small opening angles, while edge areas which are to be monitored with a lower accuracy can be scanned with a smaller number of optical elements and correspondingly larger opening angles. In the case of a complete revolution of the optical device, precisely one laser light beam is emitted by each of the first optical elements.

According to a development of the lidar device, the first optical elements are annular at a first radial distance from the axis of rotation arranged around the axis of rotation of the optical device and the second optical elements are arranged in a different from the first radial distance second radial distance from the axis of rotation annularly about the axis of rotation of the optical device.

According to a development of the lidar device, the transmitting device is arranged at the first radial distance from the axis of rotation and the receiving device is arranged at the second radial distance from the axis of rotation.

According to a development, the lidar device comprises a drive motor, which is designed to rotate the optical device at a predetermined frequency about the axis of rotation. The lidar device can thus uniformly monitor an area and detect objects.

According to a development of the lidar device, the transmitting device is designed to emit the laser light beams substantially parallel to the axis of rotation.

According to a development of the lidar device, the first optical elements and / or second optical elements differ at least partially from each other in their focal lengths and / or orientations relative to the axis of rotation of the optical device. By appropriate choice of orientation, the laser light beams can be deflected accordingly. By selecting the focal length or the alignment of the optical elements, the lidar device can be finely adjusted, since thus both different ranges and different deflections and aperture angles of the laser light beam are possible.

According to a development of the lidar device, the number of first optical elements corresponds to the number of second optical elements. Thus, each of the first optical elements corresponds to a second optical element. After emitting the laser light beam through the first optical element, the reflected laser light beam transmitted through the second optical element associated with the first optical element is received by the receiving device. By suitable choice of the first and second optical elements, these can be matched to one another. In this case, the focal length and / or the orientation of each first optical element may preferably coincide with the focal length or the orientation of the associated second optical element.

According to a development of the lidar device, the transmitting device and the receiving device are arranged on opposite sides to the axis of rotation. By this arrangement, transmitting means and receiving means are removed from each other, whereby crosstalk, that is, unwanted interference between the emitted laser light beam and the reflected laser light beam can be reduced.

According to a development of the lidar device, the first optical elements and / or second optical elements comprise at least one of: micro-optics, Fresnel lenses and diffractive elements.

According to a further development, the lidar device comprises a measuring device which is designed to measure an angular position of the optical device, and a control device which is designed to control the transmitting device by means of the angular position of the optical device measured by the measuring device such that the transmitting device controls the Laser light beams then emits when one of the first optical elements in the beam path of the laser light beam emitted by the transmitting device is located. Thus, in one complete revolution, the optical device is transmitted through each optical element exactly one laser light beam. It is prevented that a laser light beam is emitted in areas between two optical elements on the optical device. Rather, by measuring the angular position, only laser light beams are emitted through the optical elements of the plurality of first optical elements.

According to a development of the lidar device, a multiplicity of blades is arranged on the optical device, which are designed to cool the lidar device as a result of air turbulence during rotation of the optical device. The optical device serves as a cooling element at the same time and can thus help to reduce the temperature of the lidar device. Overheating during operation is prevented.

According to a development of the method, the optical device is rotated around the axis of rotation at a predetermined frequency.

According to a development of the method, the laser light beams are emitted when one of the first optical elements is located in the beam path of the laser light beam emitted by the transmitting device.

The present invention will be explained in more detail with reference to the exemplary embodiments indicated in the schematic figures of the drawings.

Show it:

1 an exploded view of a lidar device according to an embodiment of the present invention;

2 an oblique view of a lidar device according to an embodiment of the present invention;

3 a cross-sectional view of a lidar device according to an embodiment of the present invention;

4 a plan view of a front side of an optical device according to an embodiment of the present invention;

5 a plan view of a back side of an optical device according to an embodiment of the present invention;

6 and 7 Detection regions of laser light cones emitted with a lidar device according to the present invention;

8th a block diagram of a vehicle according to an embodiment of the present invention; and

9 a flowchart for explaining a method for detecting an object according to an embodiment of the invention.

1 shows an exploded view of a lidar device 100 according to an embodiment of the present invention. The lidar device 100 is further in 2 in an oblique view and in 3 illustrated in more detail in a cross-sectional view. The lidar device 100 comprises a housing consisting of a lower housing plate 2 and an upper housing cover 1 , which by means of screws 4 screwed together. At the lower housing plate 2 is a circuit board 3 attached.

Furthermore, the lidar device comprises a motor 5 which is used to drive an optical device 6 is trained.

The optical device 6 is hereby rotatable about an axis of rotation 14 stored around. The optical device 6 is disc-shaped and comprises an annular inner first portion 16 and an annular outer second region 17 , which has a flange 15 connected to each other. The first area 16 is thus opposite the second area 17 in a direction parallel to the axis of rotation 14 added.

In the first area 16 is a variety of first optical elements 12 symmetrical to the axis of rotation 14 ring around the axis of rotation 14 arranged around. Next is in the second area 17 the optical device 6 a plurality of second optical elements in turn symmetrical to the axis of rotation 14 ring around the axis of rotation 14 arranged around. The first optical elements 12 and the second optical elements 11 can in corresponding recesses in the optical device 6 be attached. The first optical elements 12 and the second optical elements 11 however, may also be a component of the optical device 6 be.

According to a further embodiment, the first optical elements 12 and the second optical elements 11 also by gluing or depositing on the optical device 6 be attached, which in this case preferably consists of a transparent substrate.

4 shows a plan view of a front side of the optical device 6 and 5 shows a plan view of a rear side of the optical device 6 , At the back of the optical device 6 are in addition to the flange 15 radially extending blades or paddle wheels 13 attached, which are formed, upon rotation of the optical device 6 the lidar device 100 to cool.

The optical elements 12 may include optical lenses or mirrors. According to embodiments, the optical elements 11 . 12 especially micro-optics and / or Fresnel lenses and / or diffractive elements. In particular, the optical elements may comprise computer-generated holograms, wherein the precise beam shape of laser light beams transmitted through the corresponding optical element may be arbitrarily set by suitable choice of the computer-generated holograms.

According to embodiments, the optical elements may also comprise combinations of lenses and / or micro-optics and / or Fresnel lenses and / or diffractive elements.

Preferably, the first optical elements differ 12 and / or the second optical elements 11 at least partially with each other in at least one of their optical properties. The optical properties include in particular the focal length and the orientation, that is the orientation with respect to the optical device 6 or the axis of rotation 14 , Laser light beams, which by different first optical elements 12 can be sent out, so can be deflected differently.

Preferably, the number of first optical elements 12 equal to the number of second optical elements 11 so that every first optical element 12 exactly a second optical element 11 assigned.

On the circuit board 3 are a transmitting device 10 and a reception device 9 appropriate. Preferably, the transmitting device is located 10 here with respect to the axis of rotation 14 on one of the receiving device 9 opposite side. transmitting device 10 and reception device 9 are thus as far away from each other as possible in order to keep the mutual influence low.

The transmitting device 10 includes at least one laser diode and is formed such, laser light beams in a direction parallel to the optical axis 14 from the circuit board 3 to send away. The first area 16 the optical device 6 is located vertically above the transmitting device 10 , Is one of the first optical elements 12 thus directly above the transmitter 10 so is the transmitting device 10 thus formed, a laser light beam through this optical element 12 through. The one from the transmitting device 10 emitted laser light beam then passes through a on the upper case cover 1 arranged transparent first window 8th through from the lidar device 100 out. The laser light beam can then be reflected by an object and hit by a on the top of the housing 1 arranged transparent second window 7 back into the lidar device 100 one. The second window 7 is located above the second area 17 the optical device 6 and the underlying receiving device 9 , The first optical elements 12 and the second optical elements 11 are here arranged such that in an angular position of the optical device 6 in which a light beam passes through one of the first optical elements 12 can pass through, a corresponding second optical element 11 directly above the receiving device 9 is located so that the reflected laser light beam through this second optical element 11 through to the receiving device 9 can meet.

Preferably, therefore, each first optical element 12 exactly a second optical element 11 assigned.

The drive motor 5 is formed, the optical device 6 with a given frequency around the axis of rotation 14 to turn around. The optical device 6 thus turns over the transmitting device 10 such that the first optical elements are successively perpendicular above the transmitting device 10 are located.

The transmitting device is designed in such a way during the rotation of the optical device 6 around the axis of rotation 14 successive laser light beams by one optical element each 12 the plurality of first optical elements 12 send out. The reception device 9 is further formed such, the laser light beam reflected on the object after passing through a corresponding optical element 11 the plurality of second optical elements 11 to recieve.

According to a preferred embodiment, the lidar device 100 a measuring device, which is designed in such a way, an angular position of the optical device 6 to eat. In particular, in this case, a pin on the optical device 6 be arranged and a photocell, the measuring device can be a position of the optical device 6 determine arranged pin. Further, the lidar device comprises 100 Preferably, a control device, which is designed in such a way, based on the measured angular position of the optical device 6 the transmitting device 10 to control such that the transmitting device 10 emits the laser light beam exactly when one of the first optical elements 12 in the beam path of the transmitting device 10 located. The transmitting device 10 thus emits laser light beams if and only if one of the first optical elements 12 directly above, that is parallel to the optical axis 14 above the transmitting device 10 located.

The flange 15 can continue crosstalk, that is unwanted interference between that of the receiving device 9 received laser light beam and possibly already in the lidar device 100 occurring reflections of the of the transmitting device 10 prevent or reduce emitted laser light beam.

In 6 is the scanning of a region with the Lidar device according to the invention 100 illustrated in more detail. In 6 in this case, light cones are shown, which each correspond to a laser light beam passing through one of the first optical elements 12 was sent through. The illustrated light cone in this case have a rectangular cross-sectional area, which is particularly when using diffractive elements as the first optical elements 12 can be enabled. However, the invention is not limited thereto. So also cone-shaped light cone can be emitted and reflected light can be received accordingly. The lidar device 100 is designed to monitor an area in front of a vehicle. In a central area here have first light cone 18 a smaller opening angle than second light cone 20 and third light cone 19 in peripheral areas. Upon rotation of the optical Facility 6 around the axis of rotation 14 becomes successively each of the pictured light cone 18 . 19 . 20 sent out exactly once. The number of light cones per solid angle here is greater in the central area than in the edge area. The corresponding opening angle and the corresponding deflection are set by suitable choice of the first optical elements, that is to say in particular the focal lengths and orientations. The second optical element respectively corresponding to the first optical element preferably has the same aperture angle and the same orientation.

In 7 are illustrated light cone according to another embodiment. The light cone differ here additionally in their range. While central light cone 21 have a long range, are more light cone 22 . 23 . 24 aligned in an edge region down to the road and thus have a shorter range.

8th shows a block diagram of a vehicle 800 with a lidar device 100 to capture an object. The lidar device 100 is here preferably formed according to one of the previous embodiments.

9 shows a flowchart for explaining a method for detecting an object. In a first method step S1, laser light beams are hereby transmitted by means of a transmitting device 10 by a first optical element 12 a plurality of first optical elements 12 one around a rotation axis 14 around rotatable optical device 6 sent out.

In a second method step S2, the laser light beams reflected on the object are transmitted after passing through an optical element 11 a plurality of second optical elements 11 the optical device 6 by means of a receiving device 9 receive. Preferably, in this case, a lidar device according to one of the above embodiments may be used.

Preferably, in this case, the optical device 6 with a given frequency around the axis of rotation 14 is turned around.

According to a preferred embodiment, the laser light beams are emitted when one of the first optical elements 12 in the beam path of the transmitter 10 emitted laser light beam is located.

On the basis of the received signals further information about the detected object can be generated. Such information may in particular comprise a distance, a speed or a shape of the object.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• EP 2657686 A1 [0005]

Claims (15)

Lidar device ( 100 ) for capturing an object, comprising: a rotation axis ( 14 ) rotatable optical device ( 6 ) comprising a multiplicity of first optical elements ( 12 ) and a plurality of second optical elements ( 11 ) having; a transmitting device ( 10 ) for emitting laser light beams; and a reception device ( 9 ) for receiving reflected laser light beams; wherein the optical device ( 6 ) is formed such that upon rotation of the optical device ( 6 ) about the axis of rotation ( 14 ) Laser light beams by means of the transmitting device ( 10 ) by an optical element ( 12 ) of the plurality of first optical elements ( 12 ) and the laser light beams reflected on the object after passing through an optical element (FIG. 11 ) of the plurality of second optical elements ( 11 ) from the receiving device ( 9 ) are received. Lidar device ( 100 ) according to claim 1, wherein the first optical elements ( 12 ) at a first radial distance from the axis of rotation ( 14 ) annularly about the axis of rotation ( 14 ) of the optical device ( 6 ) are arranged and the second optical elements ( 11 ) in a second radial distance from the axis of rotation different from the first radial distance (FIG. 14 ) annularly about the axis of rotation ( 14 ) of the optical device ( 6 ) are arranged. Lidar device ( 100 ) according to claim 2, wherein the transmitting device ( 10 ) at the first radial distance from the axis of rotation ( 14 ) and the receiving device ( 9 ) at the second radial distance from the axis of rotation ( 14 ) is arranged. Lidar device ( 100 ) according to one of the preceding claims, with a drive motor ( 5 ), which is designed such, the optical device ( 6 ) at a predetermined frequency about the axis of rotation ( 14 ) to turn around. Lidar device ( 100 ) according to one of the preceding claims, wherein the transmitting device ( 10 ) is formed such that the laser light beams substantially parallel to the axis of rotation ( 14 ). Lidar device ( 100 ) according to one of the preceding claims, wherein the first optical elements ( 12 ) and / or second optical elements ( 11 ) at least partially with each other in their focal lengths and / or orientations relative to the axis of rotation of the optical device ( 7 ). Lidar device ( 100 ) according to one of the preceding claims, wherein the number of first optical elements ( 12 ) the number of second optical elements ( 11 ) corresponds. Lidar device ( 100 ) according to one of the preceding claims, wherein the transmitting device ( 10 ) and the receiving device ( 9 ) on opposite sides to the axis of rotation ( 14 ) are arranged. Lidar device ( 100 ) according to one of the preceding claims, wherein the first optical elements ( 12 ) and / or second optical elements ( 11 ) at least one of: micro-optics, Fresnel lenses and diffractive elements. Lidar device ( 100 ) according to one of the preceding claims, with a measuring device, which is designed such, an angular position of the optical device ( 6 ) to eat; and a control device, which is designed in this way, based on the angular position of the optical device measured by the measuring device ( 6 ) the transmitting device ( 10 ) in such a way that the transmitting device ( 10 ) emits the laser light beams when one of the first optical elements ( 12 ) in the beam path of the transmitter ( 10 ) emitted laser light beam is located. Lidar device ( 100 ) according to one of the preceding claims, wherein on the optical device ( 6 ) a plurality of blades ( 13 ) is arranged, which are formed such, the lidar device ( 100 ) upon rotation of the optical device ( 6 ) to cool by air turbulence. Vehicle ( 800 ) with a lidar device ( 100 ) according to one of claims 1 to 11. Method for detecting an object, comprising the steps of: emitting (S1) laser light beams by means of a transmitting device ( 10 ) by a first optical element ( 12 ) a plurality of first optical elements ( 12 ) one about a rotation axis ( 14 ) rotatable optical device ( 6 ); and receiving (S2) laser light beams reflected on the object after passing through an optical element ( 11 ) a plurality of second optical elements ( 11 ) of the optical device ( 6 ) by means of a receiving device ( 9 ). Method according to claim 13, wherein the optical device ( 6 ) at a predetermined frequency about the axis of rotation ( 14 ) is turned around. The method of claim 13 or 14, wherein the laser light beams are emitted when one of the first optical elements ( 12 ) in the beam path of the transmitter ( 10 ) emitted laser light beam is located.

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