WO2013171069A1

WO2013171069A1 - Method for locating vehicles

Info

Publication number: WO2013171069A1
Application number: PCT/EP2013/058983
Authority: WO
Inventors: Frank Gensler
Original assignee: Bayerische Motoren Werke Aktiengesellschaft
Priority date: 2012-05-15
Filing date: 2013-04-30
Publication date: 2013-11-21
Also published as: DE102012208132A1

Abstract

The invention concerns a method for determining the position of a device, in particular a vehicle, with a recording device and a processing device, comprising; detecting a marking; determining the relative position with respect to the marking; detecting an information device which comprises information associated with the marking; detecting the information, the information allowing conclusions to be drawn about the position of the marking in a reference coordinate system; determining the position of the device in the reference coordinate system by means of the relative position and the information detected.

Description

Method for vehicle localization

The present invention relates to a method for determining the position of a device and to a device adapted for this purpose. The invention finds application, for example, in the automatic parking of motor vehicles.

The localization of devices, and particularly vehicles, using the Global Positioning System (GPS) is now widespread. In this system, by means of a receiver, electromagnetic waves are received at the device, which are emitted by satellites. By means of the reception of the electromagnetic waves, the principle of triangulation can be used to determine the position of the receiver in the geographic coordinate system.

A position determined by GPS is used for various applications, for example for route guidance or navigation in vehicles. The accuracy of positioning by GPS is variable and generally can not be considered sufficient to serve as the basis for motor vehicle parking. Furthermore, the localization by GPS in buildings such as car parks is limited, since the reception of electromagnetic waves is severely limited there. From the document WO 2006/087002 a device for moving a motor vehicle into a target position is known. The device uses a sensor device with a first part in the motor vehicle and a second part in a stationarily defined position. With the aid of the sensor device according to document WO 2006/087002, the position of the first part of the sensor device with respect to the second part of the sensor device can be determined.

From the document WO 2009/024129 a method for photog rammetric measurement of objects is known. In this procedure, signal marks on the attached object to be measured. Subsequently, the surface with the signal marks is photographed several times and overlapping. The signal marks are recognized, their position is evaluated and the signal marks are positioned to each other. In the method, the signal marks may be provided with two-dimensional codes which also indicate the size of the signal mark.

The positioning of the signal marks according to WO 2009/024129 is based on the complex evaluation of several photographs of the same signal marks in different photographs. By the method according to the publication WO 2009/024129, the position of the signal marks to each other and in space to be determined. The signal marks themselves do not contain any information about their position in space or their position relative to each other.

The object of the invention is thus to provide a method by means of which the position of a device with respect to a reference coordinate system, for example, the geographic coordinate system, can be determined. Of the wether ren it is the object of the invention to provide a corresponding device for this purpose.

SUMMARY

The object of the invention is achieved by a method for determining the position of a device according to claim 1 and a device for determining its position according to claim 12.

Further advantageous embodiments are defined in the dependent claims.

A device according to the invention is set up to determine its position. The device, in particular a passenger car (PKW), comprises a recording device, in particular a video camera, and a processing device, in particular a computer. The device detects a marker, which may be a lenticular reflector, and determines its relative position with respect on this mark. Furthermore, the device detects an identification device, in particular a sign or tablet, and information associated with the marking, which information is included in the information device and which permits a conclusion about the position of the marking in a reference coordinate system. Each detection step, or all detection steps in common, may comprise taking a picture by the recording device and processing the picture in the processing device. Preferably, the reference coordinate system is the latitude and longitude geographical coordinate system. The marker and the information device may be attached to a wall or generally to an immovable object. Finally, the device determines its position in the reference coordinate system using the relative position and the acquired information.

The system can be advantageously used for automatic or semi-automatic parking on a vacant floor space in a parking lot with multiple shelves. In this use, when entering the parking lot, a car is given a trajectory, i. a sequence of positions in geographical coordinates or in another reference coordinate system, communicated to a free parking space. Distributed in the parking lot are markers and information devices which are used together to determine the position of the vehicle. Advantageously, the markings and information devices are spatially assigned to the parking spaces. Based on the determined position and the predetermined trajectory, the car can take measures by means of the control device to maintain the predetermined trajectory, for example by issuing instructions for automatic steering and possibly accelerating or braking. Finally, the car can be spent in the free parking space.

Compared with other sensors that could be used for (semi-) automatic parking, such as 3D cameras or laser scanners, the present invention allows the use of nowadays often present in motor vehicles video cameras in combination with relatively inexpensive reflectors and signs. This avoids the use of more expensive 3D cameras or laser scanners. The invention thus relies on already existing or inexpensive systems and thus provides an economically advantageous solution.

The accuracy of the positioning by means of the present invention is sufficient, in particular in comparison to the conventional positioning by means of GPS, at least insofar as a safe parking process for passenger cars can be ensured. For example, a positional accuracy of about 5cm can be achieved.

In a preferred embodiment, the device determines the angle between a direction associated with the marker and a direction defined by the device and the marker. Furthermore, the device determines the distance between the device and the marker. The relative position of the device for marking is determined by means of the determined angle and the determined distance, and the position of the device in the reference coordinate system is then determined by means of the detected information. The directions can be represented by vectors, in particular unit vectors.

In a typical case, the direction defined by the mark is perpendicular to the extent of the mark, which in turn is itself oriented in a vertical plane.

The direction defined by the device and the marker is based on a combination of a point of the marker, such as the centroid of the marker, and a point of the capture device, such as the lens center of a camera. The center of area of the mark can be determined from the center of gravity of the mark in the picture.

According to a preferred refinement, to record the angle between a direction associated with the marking and a direction defined by the device and the marking, a recording of the marking is made and processed. In this further development, it is possible to use a marking which has a different appearance in the receptacle of the receiving device. appearance for different viewing angles (with otherwise identical conditions, in particular lighting conditions). This difference in appearance may also be perceptible to the naked eye when viewing the mark at different viewing angles. As a marker, a lenticular image, also referred to as Wackelbitd, a lenticular reflector or a reflector with lamellae, in particular with lamellae with variable angle of attack can be used. The different appearance of the marking can be realized by a well detectable, essentially vertical bar, which is located at different lateral positions of the marking as a function of the viewing angle (with otherwise identical light conditions). In a further development, it can be concluded from the lateral position of the beam in the recording of the mark in a unique manner on the angle between a direction associated with the marking and a direction defined by the device and the marking. The bar may have a different brightness than the rest of the mark.

The distance between the device and the label is preferably determined from the reduction factor of the image of the label in the image. In this case, the actual size of the marking, which can be included in the detected information, is taken into account. The marking may be at a level whose non-consideration will only marginally affect the positioning for the purpose of parking a car (for example at a height that results in positioning errors less than 1cm or less than 5cm). For example, the marking is at the same or substantially the same height as the receiving device of the device. The device may disregard the height of the mark when determining the position.

On the other hand, the mark may be at a level whose disregard significantly affects the positioning for the purpose of parking a car. In this case, the device may take into account the height of the mark when determining its position. This can be either already known or indicated by the information associated with the marking, for example in Reference to the ground on which the device or the vehicle is located or with respect to the reference coordinate system.

Instead of or in addition to the explicit indication of the height in the detected information, the device can determine the height difference between it and the mark by means of an additional angle measurement. For this purpose, a marker is used, which allows the determination of the angle of the direction defined by the marking and the device to a horizontal plane and a vertical plane. This can be realized, for example, by a marking which is formed from two adjacently arranged lenticular reflectors whose angular dependence of the appearance is oriented perpendicular to one another. The appearance of the marker would thus be, for example, a vertical bar in one part of the marker and a horizontal bar in the other part of the marker.

The direction associated with the marker may be based on the horizontal and / or vertical orientation of the angular dependence of the appearance of the marker discussed above. The horizontal orientation can be indicated for example by an angle to the north direction.

Furthermore, in an embodiment of the embodiment, the angle between a direction associated with the device and the direction defined by the device and the marking can also be determined (possibly with separate consideration of sign and magnitude). This is done by the position of the center of gravity of the mark in the recording. The device associated with the direction of the longitudinal axis of the device, in particular the vehicle correspond. The direction associated with the device, in particular if it corresponds to the longitudinal axis of a vehicle, can be taken into account when maintaining the predetermined trajectory and during the automatic movement of the vehicle into a parking space.

The information device is, for example, a sign, a sticker, a poster or the like. It serves essentially as a carrier for the information associated with the marking. The information device can be spatially related to Marking is arranged, in particular in the vicinity of the marking or adjacent to the marking or even included in the mark.

The information associated with the marking allows a conclusion about the position of the marker. The information may be the position of the marker in the reference coordinate system. If the horizontal orientation of the marker or the orientation of its angular dependence of the appearance is not known, this may also be included in the information, for example as an angle with respect to the north direction.

Furthermore, the information may indicate the size or dimensions of the marking, the height of the arrangement of the marker, the sensitivity of the angular dependence of the appearance, the vertical orientation of the angular dependence of the appearance of the marker, the vertical orientation of the marker and / or the horizontal and / or or vertical orientation of the direction associated with the marker. This information may be used alone or in combination in determining the positioning of the device.

The information may be coded by a two-dimensional code with, for example, black and white fields. In particular, the information can be reproduced by a Quick Response (QR) code.

In another embodiment, the device may include a light source and / or be capable of activating a vehicle headlamp to provide illumination of the marker allowing for robust and accurate positioning.

The device may also be an airplane or a ship. The marking is then to be attached, for example, to the terminal or to the quay wall, while the receiving device is to be attached to the aircraft or ship. The recording device may be a camera for taking still or moving pictures that can work with infrared or visible light, or both.

In the following detailed description of an embodiment of the invention, reference is made to the following figures:

FIG. 1 shows a device 1 according to an exemplary embodiment of the invention, which is set up to determine its position in an environment arranged for determining the position according to the invention in a view from above.

FIGS. 2 a to 2 c and 3 a to 3 c show various markings formed as reflectors at different viewing angles according to an exemplary embodiment of the invention.

FIG. 4 shows an exemplary information device according to the invention, here a poster 9, with covered information which is reproduced as two-dimensional code. DESCRIPTION OF A PREFERRED EMBODIMENT

Figure 1 shows, in a view from above, a passenger car (PKW) 1 according to a preferred embodiment, which is adapted to determine its position in an environment established for determining the position of the invention. The car 1 comprises a video camera 2 and a computing unit 5. The car 1 receives a lenticular reflector 3 and a shield 4 mithiife the video camera 2 and determines its relative position with respect to this reflector 3 mithiife the arithmetic unit 5. In the recording by the Video camera 2, the shield 4 and the reflector 3 associated information mithiife the arithmetic unit 5 is determined and evaluated. The information encompassed by the shield indicates for the reflector 3 its latitude and longitude, the altitude in the geographic coordinate system, and the angular orientation with respect to the north direction. The reflector 3 and the shield 4 are in this embodiment on a wall 7 attached. The car 1 finally determined using the arithmetic unit 5 its position in the coordinate system using the relative position and the information to the reflector. 3

For relative positioning, the car 1 determines the angle β between the direction R1 assigned to the reflector 3 and the direction R2 defined by the car 1 and the marking 3. Further, the car 1 determines the distance D between the car 1 and the reflector 3. Using the specific angle ß and the specific distance D, the relative position of the car 1 to the reflector 3 is determined and using the detected latitude and longitude, altitude and the angular orientation of the reflector 3 is then determined the position of the car 1 in the geographic coordinate system.

The direction R2 defined by the car 1 and the shield 3 is based on a connection of the center of area of the reflector 3 in the captured image and the lens center of the video camera. The centroid of the reflector 3 is determined based on the center of gravity of the surface of the reflector 3 in the recording.

To determine the angle β, a recording of the reflector 3 is made and processed by means of the video camera. As a reflector 3, a lenticular image, also referred to as Wacke image used. This has a different appearance for different viewing angles. The different appearance of the reflector is realized by a well detectable, substantially vertical bar, which is located at different lateral positions of the reflector 3 as a function of the viewing angle (with otherwise the same lighting conditions). The lateral positions of the beam in the receptacle are uniquely associated with an angle β between the directions R1 and R2. Figures 2a to 2c and 3a to 3c show photographs of an exemplary reflector 3 at different viewing angles (but identical, substantially uniform incidence of light). FIG. 2a shows a photograph of the reflector 3 when viewed from the right. FIGS. 2 b and 2 c each show a receptacle of the reflector 3 in the middle viewing or viewing from the left. Depending on the viewing angle, a bar of increased brightness appears at different lateral positions in the reflector 3. Figures 3a to 3c show photographs of the reflector 3 when viewed from the right, from the center and from the left. Here, a bar of reduced brightness appears at different lateral positions of the reflector 3.

The distance D is determined from the reduction factor of the image of the reflector 3 in the image taken by the video camera 2. If the actual size of the reflector 3 is not known or deviates from the usual size, the size in the information from the plate 4 is indicated.

The car 1 also determines the angle α between the longitudinal direction R3 of the car 1 and the direction R1 defined by the reflector 3. This is done by the position of the center of gravity of the surface of the reflector 3 in the captured image. The direction R3 is taken into account when maintaining the predetermined trajectory and the automatic movement of the vehicle in a parking space.

FIG. 4 shows an exemplary shield 4 which, in the form of a QR code, indicates exemplary GPS coordinates, an exemplary height, angular orientation and size of the reflector 3. The shield 4 is located next to the mark 3.

Claims

Method for determining the position of a device (1), in particular of a vehicle, having a receiving device (2) and a processing device (5), comprising:

Detecting a mark (3);

Determining the relative position with respect to the marker (3);

Detecting an information device (4) comprising information associated with the tag (3);

Acquiring the information, wherein the information allows a conclusion about the position of the marker (3) in a reference coordinate system;

Determining the position of the device (1) in the reference coordinate system using the relative position and the detected information.

The method of claim 1, wherein determining the relative position with respect to the marker (3) comprises:

Determining the angle (β) between a direction (R1) associated with the marker (3) and a direction (R2) defined by the device (1) and the marker (3);

Determining a distance (D) defined by the device (1) and the marker (3). Method according to one of claims 1 to 2, wherein the detection of the mark (3), the detection of the information device (4) and / or the detection of the information by means of a camera are performed.

Method according to one of claims 1 to 3, wherein the marking (3) comprises an artificial landmark, in particular a passive optical artificial landmark, a reflector, a reflector which has a different appearance depending on the observation, a reflector with fins and / or or a lenticular reflector.

Method according to one of claims 1 to 4, wherein the reference coordinate system in particular comprises a geographical coordinate system with latitude and longitude.

Method according to one of claims 1 to 5, wherein the information also includes one or more characteristics of the marking (3), in particular its size, the height of the attachment of the marking (3), a measure for the angular dependence of the appearance of the marking (3). and the horizontal and / or vertical orientation of the marker (3), for example, an angle with respect to the north direction comprises.

Method according to one of claims 1 to 6, wherein the information device (4) is arranged in spatial relation to the marking (3), in particular in the vicinity of the marking (3) or adjacent to the marking (3).

Method according to one of claims 1 to 7, wherein the information is reproduced in a code, in particular in a two-dimensional code, in particular a QR code.

Method according to one of claims 1 to 8, further comprising:

Determining a direction (R3) determined by the device (1), in particular the longitudinal direction of the device (1).

10. The method according to any one of claims 1 to 9, further comprising:

Determining a difference between the determined position and a predetermined position; and

Determining measures for moving the device (1) to the predetermined position.

11. The method according to any one of claims 1 to 10, further comprising:

Determining a difference between the direction (R3) determined by the device (1) and a predetermined direction; and

Determining measures for moving the device (1) in the predetermined direction.

12. A device for determining its position, comprising a receiving device (2) and a processing device (5), wherein the device is adapted to carry out a method according to one of claims 1 to 11.