METHOD AND DEVICE FOR ASCERTAINING A RELATIVE ANGLE BETWEEN TWO VEHICLES

Abstract

A method for ascertaining a relative angle between a first longitudinal axis of a towing vehicle and a second longitudinal axis of a vehicle that is mechanically coupled to the towing vehicle, including: detecting a light unit situated at the vehicle using a camera unit situated at the towing vehicle to obtain image information of the light unit; recognizing the light unit in the obtained image information, using an optical signal that is emitted by the detected light unit to obtain position information of the light unit, the position information representing a spatial position of the light unit in the image information relative to a defined reference point; ascertaining the relative angle between the first longitudinal axis of the towing vehicle and the second longitudinal axis of the vehicle, using the position information of the detected light unit; and emitting a signal as a function of the ascertained relative angle.

Claims

1-13. (canceled)

14. A method for ascertaining a relative angle between a first longitudinal axis of a towing vehicle and a second longitudinal axis of a vehicle that is mechanically coupled to the towing vehicle, the method comprising the following steps: detecting a light unit situated at the vehicle using a camera unit situated at the towing vehicle to obtain image information of the light unit; recognizing the light unit in the obtained image information using an optical signal that is emitted by the detected light unit to obtain a piece of position information of the light unit, the position information representing a spatial position of the light unit in the image information relative to a defined reference point; ascertaining the relative angle between the first longitudinal axis of the towing vehicle and the second longitudinal axis of the vehicle, using the position information of the detected light unit; and emitting a signal as a function of the ascertained relative angle.

15. The method as recited in claim 14, further comprising the following step: comparing the position information of the light unit to pieces of position information of the light unit stored in a characteristic map, to ascertain the relative angle.

16. The method as recited in claim 14, wherein the relative angle is ascertained using a piece of distance information that represents a spatial distance between the two vehicles.

17. The method as recited in claim 14, wherein the optical signal emitted by the light unit has a defined pattern with an intensity that is variable over time and/or a frequency that is variable over time.

18. The method as recited in claim 14, further comprising the following step: emitting a control signal using a control unit situated at the towing vehicle to control the emission of the optical signal using the light unit situated at the vehicle.

19. The method as recited in claim 18, wherein the control signal is emitted when reverse travel of the towing vehicle is initiated when a reverse gear is engaged at the towing vehicle.

20. The method as recited in claim 14, further comprising the following step: emitting the optical signal using the light unit situated at the vehicle.

21. The method as recited in claim 14, wherein the detection of the light unit includes a detection of a first light unit situated at the vehicle and a detection of a second light unit situated at the vehicle to obtain a first piece of image information of the first light unit and a second piece of image information of the second light unit, the first light unit in the first piece of image information being recognized based on a first optical signal that is emitted by the first detected light unit, and the second light unit in the second piece of image information being recognized based on a second optical signal that is emitted by the second detected light unit.

22. The method as recited in claim 21, wherein: the second light unit is different from the first light unit, and/or the second optical signal is different from the first optical signal, and/or the second piece of image information is different from the first piece of image information.

23. The method as recited in claim 14, wherein the camera unit is a camera unit that is already present at the towing vehicle, and/or the light unit is a light unit that is already present on the vehicle.

24. A non-transitory machine-readable memory medium on which is stored a computer program, the compute program, when executed by a computer, causing the computer to perform the following: recognize a light unit, situated at a vehicle, in image information, using an optical signal that is emitted by the light unit, to obtain position information of the light unit, the light unit having been detected using a camera unit situated at a towing vehicle that is mechanically coupled to the vehicle, the position information representing a spatial position of the light unit in the image information relative to a defined reference point; and ascertain a relative angle between a first longitudinal axis of the towing vehicle and a second longitudinal axis f the vehicle, using the position information of the detected light unit.

25. A control unit that is configured to: recognize a light unit, situated at a vehicle, in image information, using an optical signal that is emitted by the light unit to obtain position information of the light unit, the light unit having been detected using a camera unit situated at a towing vehicle that is mechanically coupled to the vehicle, the position information representing a spatial position of the light unit in the image information relative to a defined reference point; ascertain a relative angle between a first longitudinal axis of the towing vehicle and a second longitudinal axis of the vehicle, using the position information of the detected light unit; and emit a control signal as a function of the ascertained relative angle.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0042] The present invention is explained in greater detail below by way of example, with reference to the figures.

[0043] FIGS. 1A through 1F show a schematic illustration of a maneuvering tractor-trailer.

[0044] FIG. 2 shows a schematic illustration of a communication protocol according to one exemplary embodiment.

[0045] FIG. 3 shows a flow chart of a method according to one exemplary embodiment.

DETAILED DESCRIPTION OF EXAMPLE EMBODIMENTS

[0046] FIGS. 1A and 1D illustrate a top view onto a maneuvering tractor-trailer in accordance with an example embodiment of the present invention, which is provided overall with reference numeral 10.

[0047] Tractor-trailer 10 includes a towing machine 12 and a semitrailer 14. Semitrailer 14 is mechanically coupled to towing machine 12 with the aid of a fifth wheel coupling 16.

[0048] Towing machine 12 includes a driving cab 18, a control unit 20, and two video cameras 22, 24 that are part of a mirror replacement system of towing machine 12. Semitrailer 14 includes four marker lights 26, 28, 30, 32.

[0049] Video cameras 22, 24 are situated on the right and left sides of driving cab 18 of towing machine 12. Video cameras 22, 24 are oriented with their detection ranges 34, 36 opposite a preferred or prevailing travel direction 38 of tractor-trailer 10 in order to detect marker lights 26, 28, 30, 32 of semitrailer 14.

[0050] Two marker lights 26, 28 are situated on the right and left sides of a front area of semitrailer 14 along preferred travel direction 38. The further two marker lights 30, 32 are situated on the right and left sides of a rear area of semitrailer 14 along preferred travel direction 38. Marker lights 26, 28, 30, 32 are oriented along preferred travel direction 38 in order to emit or radiate an optical signal 40, 42, 44, 46 in the direction of towing machine 12.

[0051] Control unit 20 of towing machine 12 is designed to emit a control signal to marker lights 26, 28, 30, 32 with the aid of a hard-wired connection when reverse travel of tractor-trailer 10 opposite preferred travel direction 38 is initiated, in order to control the emission of optical signals 40, 42, 44, 46.

[0052] FIGS. 1B and 1C show image information 48, 50, obtained from left video camera 22 and right video camera 24, respectively, in the form of detected camera recordings 48, 50 at a relative position between towing machine 12 and semitrailer 14 as illustrated in FIG. 1A.

[0053] Left camera recording 48 shows left front marker light 26 and left rear marker light 30. Spatial positions 52, 54 of the two left marker lights 26, 30 are identical to respective reference points 60, 62 at the present relative position.

[0054] Analogously, right camera recording 50 shows right front marker light 28 and right rear marker light 32. Spatial positions 56, 58 of the two right marker lights 28, 32 are likewise identical to respective reference points 64, 66 at the present relative position.

[0055] Control unit 20 is designed to recognize marker lights 26, 28, 30, 32 in camera recordings 48, 50, using optical signals 40, 42, 44, 46 that are emitted by detected marker lights 26, 28, 30, 32, in order to obtain position information concerning marker lights 26, 28, 30, 32.

[0056] In addition, control unit 20 is designed to ascertain a relative angle of zero degrees between a first longitudinal axis 70 of towing machine 12 and a second longitudinal axis 72 of semitrailer 14, based on agreement of spatial positions 52, 54, 56, 58 with respective reference points 60, 62, 64, 68.

[0057] FIG. 1D illustrates tractor-trailer 10 with a relative position between towing machine 12 and semitrailer 14 which is different from the relative position shown in FIG. 1A.

[0058] FIGS. 1E and 1F once again show camera recordings 48′, 50′ detected by left video camera 22 and right video camera 24, respectively, at a relative position between towing machine 12 and semitrailer 14 as illustrated in FIG. 1D.

[0059] In this case, left camera recording 48′ shows only left front marker light 26 of semitrailer 14 due to the maneuvering of tractor-trailer 10. At the present relative position, spatial position 52′ of left front marker light 26 is different from corresponding reference point 60.

[0060] Right camera recording 50′ shows only right rear marker light 32. At the present relative position, spatial position 58′ of right rear marker light 32 is different from corresponding reference point 66.

[0061] Control unit 20 is designed to ascertain a relative angle w between first longitudinal axis 70 of towing machine 12 and second longitudinal axis 72 of semitrailer 14, based on the deviation of spatial positions 52′, 58′ from respective reference points 60, 66. Relative angle w is different from zero.

[0062] FIG. 2 shows a flow chart of one possible exemplary embodiment of a method according to the present invention for ascertaining the relative angle between first longitudinal axis 70 of towing machine 12 and second longitudinal axis 72 of semitrailer 14 which is mechanically coupled to towing machine 12.

[0063] The method is provided overall with reference numeral 100.

[0064] A control signal is emitted in step 110 with the aid of control unit 20 of towing machine 12, when a reverse gear is engaged at towing machine 12 to initiate reverse travel of tractor-trailer 10, in order to control or activate the emission of optical signals 40, 42, 44, 46 with the aid of marker lights 26, 28, 30, 32 situated at semitrailer 14.

[0065] Optical signals 40, 42, 44, 46 are emitted in step 120 with the aid of marker lights 26, 28, 30, 32 situated at semitrailer 14, optical signals 40, 42, 44, 46 emitted by marker lights 26, 28, 30, 32 each having a defined pattern, a so-called “blinking pattern,” with an intensity that is variable over time.

[0066] Marker lights 26, 28, 30, 32 situated at semitrailer 14 are detected in step 130 with the aid of video cameras 22, 24 situated at towing machine 12 in order to obtain camera recordings 48, 48′, 50, 50′ of marker lights 26, 28, 30, 32.

[0067] Marker lights 26, 28, 30, 32 in obtained camera recordings 48, 48′, 50, 50′ are recognized in step 140, using optical signals 40, 42, 44, 46 that are emitted by detected marker lights 26, 28, 30, 32, in order to obtain the position information of marker lights 26, 28, 30, 32. The position information represents spatial positions 52, 52′, 54, 56, 58, 58′ of marker lights 26, 28, 30, 32 in camera recordings 48, 48′, 50, 50′ relative to defined reference points 60, 62, 64, 66.

[0068] Relative angle w between first longitudinal axis 70 of towing machine 12 and second longitudinal axis 72 of semitrailer 14 is ascertained in step 150, using position information 52, 52′, 54, 56, 58, 58′of detected marker lights 26, 28, 30, 32.

[0069] Lastly, a signal is emitted as a function of the ascertained relative angle in step 160.

[0070] FIG. 3 schematically illustrates by way of example a communication protocol between control unit 20 of towing machine 12 and one of marker lights 26 or a control unit of marker light 26.

[0071] A control signal S1 is emitted by hard-wire from control unit 20 to the control unit of marker light 26 in step 210 when a reverse gear is engaged at towing vehicle 12, in order to activate the emission of optical signal 40 having a defined temporal pattern in step 220.

[0072] An acknowledgement signal C1 is emitted by hard-wire from the control unit of marker light 26 to control unit 20 of towing machine 12 in step 230 in order to acknowledge the emission of optical signal 40 having the defined temporal pattern.

[0073] After marker light 26 is recognized, using optical signal 40 emitted by marker light 26, an acknowledgement signal C2 is emitted by hard-wire from control unit 20 of towing machine 12 to the control unit of marker light 26 in step 240 in order to acknowledge the recognition of marker light 26.

[0074] A further control signal S2 that is different from first control signal S1 is emitted by hard-wire from control unit 20 of towing machine 12 to the control unit of marker light 26 in step 250 in order to end the emission of temporal pattern in step 260 and to activate the emission of a further optical signal 40′, having a further defined temporal pattern that is different from the defined temporal pattern, in step 270.

[0075] An acknowledgement signal C3 is emitted by hard-wire from the control unit of marker light 26 to control unit 20 of towing machine 12 in step 280 in order to acknowledge the emission of further optical signal 40′ having the further defined temporal pattern.

[0076] If an exemplary embodiment includes an “and/or” linkage between a first feature and a second feature, this is to be construed in such a way that according to one specific embodiment, the exemplary embodiment includes the first feature as well as the second feature, and according to another specific embodiment includes only the first feature or only the second feature.