DE102008020839A1 - Method and device for determining a position and / or an orientation of a camera - Google Patents

Abstract

The invention relates to a method and a device for determining a position and / or an orientation of a camera (8) arranged on a second vehicle member (3) of an articulated vehicle (1) relative to a first vehicle member (2). In this case, the instantaneous position and / or an orientation of the camera (8) is determined from a currently determined distance of a first antenna (5) arranged on the second vehicle member (3) from a second antenna (6) arranged on the first vehicle member (2). a currently determined inclination angle (Theta1) of a longitudinal axis (11) and a currently determined inclination angle (Theta2) of a transverse axis (12) of the first and / or second vehicle member (3), the positions of the first antenna (5) and the camera (8 ) on the second vehicle link (3) and the second antenna (6) on the first vehicle link (2) and a currently determined distance of a third antenna (7) arranged on one of the vehicle links (2, 3) from the first antenna (5) or the second antenna (6) and / or by an evaluation of the camera (8) and / or another arranged on the articulated vehicle (1) optical sensor image data and / or a time course of the distance of he Most antenna (5) from the second antenna (6) and / or a time course of a steering angle of the articulated vehicle (1).

Description

The The invention relates to a method and a device for detection a position and / or orientation of a camera.

commercial vehicles to goods or passenger transport often have two or more articulated vehicle links on. Examples are articulated vehicles with a tractor and a semi-trailer and articulated buses with two or three against each other movable car parts. Such vehicles are in this document referred to as articulated vehicles.

There the teachings of this writing equally for vehicle team apply, consisting of a towing vehicle and one or more vehicle trailers Vehicle combinations are also among the numbered articulated vehicles.

Under Vehicle members of a structured vehicle, the individual over Joints connected and mutually movable units of the articulated vehicle understood. The vehicle links of a semitrailer vehicle with a tractor and a semi-trailer are therefore the tractor and the semi-trailer, the vehicle links of a vehicle combination are the towing vehicle and the vehicle trailer (s).

Especially To facilitate maneuvering of an articulated vehicle is it is advantageous to the articulated vehicle and an environment thereof, especially an environment behind him, from a bird's eye view to represent on a screen that for a driver the articulated vehicle is visible.

A Such representation of the articulated vehicle and an environment the same can for example by means of a in a front vehicle link the articulated vehicle arranged control unit be determined by using images from one a rear vehicle member of the articulated vehicle arranged Camera to be captured. This requires a precise knowledge of the position and alignment of the camera relative to the front vehicle link.

From the US 5,913,078 is a camera with an integrated antenna, an integrated tilt sensor and an integrated direction sensor known. By means of the antenna, electromagnetic waves, in particular GPS signals (GPS = Global Positioning System) for position determination, can be received. From the signals received from the antenna, a position of the camera can be determined. By means of the directional and inclination sensors, an orientation of the camera and therefrom a direction in which the photograph is taken can be determined.

From the DE 10 2006 059 804 A1 a device for determining the position and measurement of vehicle components is known. The device comprises a movable probe, by means of which pseudo-noise-coded signals are transmitted via at least one antenna, a number of stationary receiving devices, by means of which signals emitted by the probe are received, and evaluation elements, by means of which runtime differences of the signals received by the receiving devices the position of a location defined by the probe is determined.

Of the Invention is based on the object, an apparatus and a method to determine a position and / or an orientation Camera arranged on an articulated vehicle relative to a Specify vehicle member of the articulated vehicle.

The Object is achieved by an arrangement having the features specified in claim 1 and a method with solved the specified in claim 9 or 11 features.

advantageous Embodiments of the invention are the subject of the dependent claims.

at one of the methods of the invention are a Position and / or an orientation of a on a second vehicle member an articulated vehicle arranged camera relative to a first vehicle member determined from intervals one at the second vehicle member arranged first antenna of two at the first vehicle member arranged further antennas, a tilt angle a longitudinal axis and a tilt angle of a transverse axis the first and / or second vehicle member and the positions of the first antenna and the camera on the second vehicle member and the two other antennas on the first vehicle member.

In an alternative method according to the invention, a position and an orientation of a camera arranged on a second vehicle member of an articulated vehicle relative to a first vehicle member are determined from a distance of a first antenna arranged on the second vehicle member from a second antenna arranged on the first vehicle member, an inclination angle a longitudinal axis and an inclination angle of a transverse axis of the first and / or second vehicle member, the positions of the first antenna and the camera on the second vehicle member and the second antenna on the first driving generator member and by means of an evaluation of the camera or other arranged on the articulated vehicle optical sensor detected image data and / or a time profile of the distance of the first antenna from the second antenna and / or a time course of a steering angle of the articulated vehicle.

there In both methods, the distance between two antennas is one Runtime measurement and / or angle measurement and / or level measurement of Radio signals of one of the two antennas determines which of the other of the two antennas are received, and the tilt angle be by at least one of the first and / or second vehicle member arranged tilt sensor determined.

The Inventive device for determining a Position and an orientation of a at a second vehicle member an articulated vehicle arranged camera relative to a first Vehicle member is characterized by a on the second vehicle member arranged first antenna, one arranged on the first vehicle member second antenna having a frequency range corresponding to the first antenna, at least one arranged on the first and / or second vehicle member Tilt sensor and a control unit, by the antennas and the at least one tilt sensor and the camera and / or a steering angle sensor of the articulated vehicle detected data can be fed, which make up a position and orientation the camera relative to a first vehicle member can be determined.

there is advantageously at least one of the tilt sensors and or the first antenna integrated into the camera. This reduces the number of components and facilitates their assembly.

Further At least one of the tilt sensors is preferably a so-called thermodynamic inclination sensor. This has the advantage that by means of of such a tilt sensor simultaneously and with a high Accuracy the tilt angle can be detected.

Prefers the first antenna has a range that's bigger as the maximum distance between the first antenna and the second one Antenna is so that emitted from the first antenna radio signals can be received by the second antenna.

alternative or in addition, the second antenna has a range, which is greater than the maximum distance between the first antenna and the second antenna is, so from the second Antenna emitted radio signals by means of the first antenna receivable are.

A Embodiment of the device according to the invention further sees a arranged on the first vehicle member third Antenna with a frequency range corresponding to the first antenna within the range of the first antenna before, with the control unit can be fed from the third antenna received radio signals are. This can advantageously by means of the first antenna emitted radio signals the distances of the second and third antenna are determined by the first antenna. This facilitates the positioning of the camera and increases their accuracy.

alternative may be a third antenna with a corresponding to the second antenna Frequency range within the range of the second antenna be arranged the second vehicle member. Thereby can by radio signals emitted by the second antenna, the distances the first and third are determined by the second antenna.

Further Advantages, features and details of the invention are described below based on embodiments with reference to drawings described. The drawings are schematic representations and demonstrate:

1 an articulated vehicle with three antennas in a plan view,

2 an inclination angle of a longitudinal and a transverse axis of a vehicle member, and

3 an articulated vehicle with two antennas in a plan view.

each other corresponding parts are in all figures with the same reference numerals Mistake.

1 shows a plan view of an articulated vehicle 1 with a front, first vehicle member 2 and a rear, second vehicle member 3 , The two vehicle links 2 . 3 are connected by a joint, so they face each other around a coupling point 4 are mobile.

At the second vehicle member 3 are a first antenna 5 , a camera 8th and a tilt sensor 9 firmly arranged. At the first vehicle member 2 are a second antenna 6 and a third antenna 7 firmly arranged. For example, the second antenna 6 on a passenger-side exterior mirror and the third antenna 7 arranged on a driver's side mirror. The first antenna 5 , the camera 8th and the tilt sensor 9 For example, at a rear end of the second vehicle member 3 arranged. Alternatively, the components may each be on the other vehicle be arranged member or in any other combination on the vehicle members.

A bending angle α between the two vehicle links 2 . 3 is defined as the angle between a longitudinal axis 10 of the first vehicle member 2 through the coupling point 4 and a longitudinal axis 11 of the second vehicle member 3 through the coupling point 4 ,

The frequency ranges of the antennas 5 . 6 . 7 correspond to each other and lie for example in the gigahertz range. The range of the first antenna 5 is sized such that from the first antenna 5 emitted radio signals from the second antenna 6 and the third antenna 7 can be received at any kink angle α.

To a current position of the camera 8th relative to the first vehicle member 2 to be determined, according to the invention instantaneous distances of the first antenna 5 from the second antenna 6 and the third antenna 7 certainly. These distances are determined by a transit time measurement and / or level measurement and / or angle measurement by means of the first antenna 5 emitted radio signals determined which of the second antenna 6 and the third antenna 7 be received.

From the determined instantaneous distances of the first antenna 5 from the second antenna 6 and the third antenna 7 and the known fixed positions of the first antenna 5 and the camera 8th on the second vehicle member 3 and the second antenna 6 and the third antenna 7 on the first vehicle member 2 becomes a current position of the camera 8th relative to the first vehicle member 2 certainly.

By means of the inclination sensor 9 become an inclination angle θ _{1 of} the longitudinal axis 11 and an inclination angle θ _{2 of} a transverse axis 12 of the second vehicle member 3 certainly.

It is according to 2 the inclination angle θ _{1 of} the longitudinal axis 11 for example, defined as the angle between a vector 13 pointing in the direction of gravity, and a vector 14 that is along the longitudinal axis 11 from the coupling point 4 to the rear end of the second vehicle member 3 is directed. Accordingly, the inclination angle θ ₂ becomes the transverse axis 12 Are defined.

A suitable tilt sensor 9 for the determination of the inclination angle θ ₁ , θ ₂ is for example a so-called thermodynamic inclination sensor.

From the angles of inclination θ ₁ , θ ₂ and the known fixed arrangement of the camera 8th on the second vehicle member 3 becomes the orientation of the camera 8th certainly.

The above-described determination of the position and orientation of the camera 8th is carried out by means of a control unit, not shown, preferably in the first vehicle member 2 is arranged. These are the controller from the second antenna 6 and the third antenna 7 received radio signals and measuring signals of the inclination sensor 9 supplied and stored in the control unit data showing the geometry of the articulated vehicle 1 and the arrangement of the antennas 5 . 6 . 7 , the camera 8th and the tilt sensor 9 at the vehicle links 2 . 3 describe.

A development of this embodiment provides a further inclination sensor, which on the first vehicle member 2 is arranged and whose measuring signals are supplied to the control unit. As a result, advantageously also an inclination of the first vehicle member 2 and a tilt of the two vehicle links 2 . 3 be determined against each other.

3 shows an apparatus for an alternative method for determining the position and orientation of the camera 8th on the second vehicle member 3 , Unlike the in 1 shown device has the articulated vehicle 1 only two antennas 5 . 6 on, with a first antenna 5 on the second vehicle member 3 and a second antenna 6 on the first vehicle member 2 is arranged.

For determining the position of the camera 8th relative to the first vehicle member 2 As described above, a current distance of the first antenna 5 to the second antenna 6 by means of radio signals of the first antenna 5 determined.

From the determined distance and the known positions of the antennas 5 . 6 and the camera 8th at the vehicle links 2 . 3 In general, there are two possible positions of the camera 8th relative to the first vehicle member 2 ,

The geometric situation becomes clear in a fixed with the first vehicle member 2 related reference system, ie a reference system in which the first vehicle member 2 rests. The following is assumed to be the articulated vehicle 1 located on a level surface and the two antennas 5 . 6 have the same distance to the ground. Otherwise, the following remarks apply in a form adapted to a changed situation.

In the chosen frame of reference, the first antenna moves 5 with changing kink Angle α on a circular arc K around a circle center M, which is perpendicular to the coupling point 4 the vehicle links 2 . 3 lies.

A straight line G through the location of the second antenna 6 and the circle center M has with the arc K a first intersection A and a second intersection B, wherein the first intersection point A of the second antenna 6 farther away than the second intersection B is.

The first intersection A has the greatest distance D _max from the second antenna of all locations on the arc K. 6 , The second intersection B has the smallest distance D _min from the second antenna of all locations on the arc K. 6 ,

Starting from the second point of intersection B takes on the arc K, the distance to the second antenna 6 monotonically up to the first intersection point A. Therefore, each two lying symmetrically to the line G locations on the arc K have the same distance from the second antenna 6 ,

For a determined distance of the first antenna 5 to the second antenna 6 the location of the first antenna 5 Therefore, the current position of the first antenna must be clearly determined on the arc K 5 relative to the straight line G are determined. It is under the location of the first antenna 5 relative to the straight line G understood the side of the line G, on which the first antenna 5 located.

For this purpose, an embodiment of the method provides an evaluation of by means of the camera 8th captured images on which the first vehicle member is at least partially visible. This sets a suitably trained camera 8th for example, an omnidirectional camera 8th , and a corresponding arrangement of the camera 8th ahead.

To determine the position of the first antenna 5 relative to the straight line G, the images captured by the camera are supplied to the control unit and evaluated by the control unit accordingly. By way of example, the location of a location or object on the first vehicle element can be determined by object recognition 2 in one of the first camera 5 captured image and therefrom the location of the first antenna 5 be determined relative to the straight line G by means of a stored in the control unit map. The map maps the location of the location or object to the first vehicle link 2 in the picture a position of the first antenna 5 relative to the straight line G too.

Alternatively or additionally, another camera for capturing images of the first vehicle member 2 on the second vehicle member 3 can be arranged and captured by this additional camera images can be evaluated accordingly.

Another embodiment provides an evaluation of the time course of the determined distance of the antennas 5 . 6 in front. It exploits that a position of the first antenna 5 relative to the straight line G can only change if the first antenna 5 traverses the first intersection A or the second intersection B. Therefore, with known initial position of the first antenna 5 relative to the straight line G, the time course of the determined distance of the second antenna 6 to the first antenna 5 evaluated.

As long as the determined distance does not assume the greatest distance D _max or the smallest distance D _min , the position of the first antenna remains 5 relative to the straight line G unchanged from the initial position.

If the greatest distance D _max or smallest distance D _{min is} reached, a time derivative of the distance is evaluated, which is determined by subtraction of temporally successive distance values. If the time derivative is significantly different from zero, then a change in the location of the first antenna 5 relative to the straight line G found.

Otherwise, for example, by evaluating a time course of a steering angle of the articulated vehicle and / or an evaluation of means of the camera 8th captured images decided if the location of the first antenna 5 relative to the straight line G changes.

In this case, for example, to a change in the position of the first antenna 5 closed relative to the straight line G, when the steering angle does not change significantly when reaching the maximum distance D _max or the smallest distance D _min .

Alternatively or additionally, the time course of by means of the camera 8th evaluated images evaluated. For example, the course of the position of an object in an image can then be evaluated as to whether this position changes its direction of movement within the image when the greatest distance D _max or the smallest distance D _{min is reached} . If it does not do so, it will change the position of the first antenna 5 closed relative to the straight line G.

1

structured vehicle

2

first vehicle link

3

second vehicle link

4

coupling point

5

first antenna

6

second antenna

7

third antenna

8th

camera

9

tilt sensor

10

longitudinal axis of the first vehicle member

11

longitudinal axis of the second vehicle member

12

transverse axis of the second vehicle member

13

vector in the direction of Earth's gravity

14

vector along a longitudinal axis

α

bending angle

θ ₁

tilt angle a longitudinal axis

θ ₂

tilt angle a transverse axis

K

arc

M

Circle center

G

Just

A

first intersection

B

second intersection

D _max

largest Distance of the first from the second antenna

D _min

smallest Distance of the first from the second antenna

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• US 5913078 [0007]
• - DE 102006059804 A1 [0008]

Claims (13)

Device for determining a position and / or an orientation on a second vehicle member ( 3 ) of an articulated vehicle ( 1 ) arranged camera ( 8th ) relative to a first vehicle member ( 2 ), characterized by a on the second vehicle member ( 3 ) arranged first antenna ( 5 ), one on the first vehicle member ( 2 ) arranged second antenna ( 6 ) with one to the first antenna ( 5 ) corresponding frequency range, at least one at the first and / or second vehicle member ( 3 ) arranged tilt sensor ( 9 ) and a control unit to which the antennas ( 5 . 6 ) and the at least one inclination sensor ( 9 ) as well as the camera ( 8th ) and / or a steering angle sensor of the articulated vehicle ( 1 ) can be supplied, from which a position and orientation of the camera ( 8th ) relative to a first vehicle member ( 2 ) can be determined. Device according to claim 1, characterized in that at least one of the inclination sensors ( 9 ) into the camera ( 8th ) is integrated. Device according to claim 1 or 2, characterized in that at least one of the tilt sensors ( 9 ) is a thermodynamic tilt sensor. Device according to one of claims 1 to 3, characterized in that the first antenna ( 5 ) into the camera ( 8th ) is integrated. Device according to one of claims 1 to 4, characterized in that the first antenna ( 5 ) has a range greater than a _maximum distance (D _max ) between the first antenna ( 5 ) and the second antenna ( 6 ), so that from the first antenna ( 5 ) emitted by the second antenna ( 6 ) are receivable. Device according to one of claims 1 to 5, characterized in that the second antenna ( 6 ) has a range greater than the maximum distance (D _max ) between the first antenna ( 5 ) and the second antenna ( 6 ), so that from the second antenna ( 6 ) emitted radio signals by means of the first antenna ( 5 ) are receivable. Apparatus according to claim 5, characterized in that on the first vehicle member ( 2 ) a third antenna ( 7 ) with one to the first antenna ( 5 ) corresponding frequency range within the range of the first antenna ( 5 ) and the control unit of the third antenna ( 7 ) received radio signals can be fed. Apparatus according to claim 6, characterized in that on the second vehicle member ( 3 ) a third antenna ( 7 ) with one to the second antenna ( 6 ) corresponding frequency range within the range of the second antenna ( 6 ) and the control unit of the third antenna ( 7 ) received radio signals can be fed. Method for determining a position and / or an orientation of a vehicle member ( 3 ) of an articulated vehicle ( 1 ) arranged camera ( 8th ) relative to a first vehicle member ( 2 ), characterized in that on the basis of currently determined distances one at the second vehicle member ( 3 ) arranged first antenna ( 5 ) of two on the first vehicle member ( 2 ) arranged further antennas ( 6 . 7 ), a currently determined inclination angle (θ ₁ ) of a longitudinal axis ( 11 ) and a currently determined inclination angle (θ ₂ ) of a transverse axis ( 12 ) of the first and / or second vehicle member ( 3 ) and the positions of the first antenna ( 5 ) and the camera ( 8th ) on the second vehicle member ( 3 ) and the two other antennas ( 6 . 7 ) on the first vehicle member ( 2 ) the current position and / or the current orientation of the camera ( 8th ) is determined. Method according to claim 9, characterized in that the distance between two antennas ( 5 . 6 . 7 ) by a transit time measurement and / or angle measurement and / or level measurement of radio signals of one of the two antennas ( 5 . 6 . 7 ), which of the other of the two antennas ( 5 . 6 . 7 ) are received. Method for determining a position and / or an orientation of a vehicle member ( 3 ) of an articulated vehicle ( 1 ) arranged camera ( 8th ) relative to a first vehicle member ( 2 ), characterized in that on the basis of a currently determined distance one at the second vehicle member ( 3 ) arranged first antenna ( 5 ) of one on the first vehicle member ( 2 ) arranged second antenna ( 6 ), a currently determined inclination angle (θ ₁ ) of a longitudinal axis ( 11 ) and a currently determined inclination angle (θ ₂ ) of a transverse axis ( 12 ) of the first and / or second vehicle member ( 3 ), the positions of the first antenna ( 5 ) and the camera ( 8th ) on the second vehicle member ( 3 ) and the second antenna ( 6 ) on the first vehicle member ( 2 ) as well as by an evaluation of the camera ( 8th ) and / or another on the articulated vehicle ( 1 ) arranged optical sensor detected image data and / or a time course of the distance of the first antenna ( 5 ) from the second antenna ( 6 ) and / or a time course of a steering angle of the articulated vehicle ( 1 ) the current position and / or orientation of the camera ( 8th ) is determined. Method according to one of claims 10 or 11, characterized in that the distance of first antenna ( 5 ) from the second antenna ( 6 ) by a transit time measurement and / or angle measurement and / or level measurement of radio signals of one of the two antennas ( 5 . 6 ), which of the other of the two antennas ( 5 . 6 ) are received. Method according to one of claims 9 to 12, characterized in that the inclination angles (θ ₁ , θ ₂ ) by means of at least one of the first and / or second vehicle member ( 3 ) arranged inclination sensor ( 9 ) be determined.