Method for preventing critical situations involving a vehicle combination, wherein a distance between points is determined from the vehicle combination, driver assistance system and motor vehicle

Abstract

Method for preventing a critical situation involving a vehicle combination (3) consisting of a motor vehicle (1) and a trailer (2) attached to it, comprising the following steps: - Capturing a shape of an area (6) of the motor vehicle (1) facing the trailer (2); - Capturing a shape of an area (7) of the trailer (2) facing the motor vehicle (1); characterized by the steps: - Determining at least one first characteristic point (8) in the area (6) of the motor vehicle (1) at which, in the critical situation, the motor vehicle (1) would touch the trailer (2); - Determine at least one second characteristic point (9) in the area (7) of the trailer (2) at which, in the critical situation, the trailer (2) would touch the motor vehicle (1); - Determining a distance (D L) between the first characteristic point (8) and the second characteristic point (9) in a driving operation of the motor vehicle (1); - Generating a control signal for a functional unit (13, 14) of the motor vehicle (1) and / or the trailer (2) when a predetermined distance threshold is undershot by the specified distance (D L ) between the first characteristic position (8) and the second characteristic position (9); and - Sending the control signal to the functional unit (13, 14) and setting an operating state of the functional unit (13, 14) to prevent the critical situation, whereby a rate of change of distance between at least the first characteristic point (8) and the second characteristic point (9) is determined and a control signal for the functional unit (13, 14) is generated depending on the rate of change of distance.

Description

[0001] The invention relates to a method for preventing a critical situation involving a combination comprising a motor vehicle and a trailer attached to it. A detection device detects the shape of an area of ​​the motor vehicle facing the trailer. A detection direction detects the shape of an area of ​​the trailer facing the motor vehicle. Furthermore, the invention relates to a driver assistance system and a motor vehicle.

[0002] Methods are already known from the prior art that prevent a critical situation between a motor vehicle and a trailer attached to the motor vehicle. In particular, an angle between the motor vehicle and the trailer is detected, and depending on the angle, a functional unit of the motor vehicle can be controlled accordingly to prevent the critical situation.

[0003] For example, DE 10 2010 033 381 A1 discloses a method for controlling a vehicle and a trailer. The motor vehicle has a front and a rear end, and the trailer is coupled to the rear end. The method comprises detecting a plurality of vehicle characteristics, detecting a distance between the vehicle and the trailer with at least one sensor positioned at the rear end of the vehicle, determining a vibration of the trailer based on the detected distance, and applying a braking force to at least one wheel of the motor vehicle in response to the vibration. The method known from the prior art serves in particular to detect and prevent a so-called skidding situation when the motor vehicle is traveling forward with the trailer attached.However, such vibration would not occur, particularly when driving slowly, especially when reversing into a parking space, so that a critical situation would not be reliably detected when driving slowly.

[0004] DE 10 2005 027 846 A1 discloses a vehicle combination comprising a towing vehicle and at least one trailer, wherein the towing vehicle and / or the trailer comprises a means by means of which a value representing the angle between the towing vehicle and the trailer can be determined, further comprising a control unit for controlling a braking device which is protected from mutual damage when turning in that the braking device of the vehicle and / or the trailer is actuated by the control unit independently of the driver when a maximum value of the angle between the towing vehicle and the trailer is exceeded.

[0005] DE 10 2013 107 710 A1 discloses an agricultural tractor-trailer combination, comprising a towing vehicle and a trailer towed by the towing vehicle, wherein during operation when cornering a distance is established between the trailer and the towing vehicle depending on a curve radius of the tractor-trailer combination, with a sensor with the aid of which an actual value which is dependent on the current distance between the trailer and the towing vehicle or corresponds to this current distance can be measured, with an evaluation device with the aid of which the measured actual value can be evaluated in such a way that when the actual value reaches a first limit value, a warning signal can be generated which changes with increasing change in the actual value starting from the first limit value towards a second limit value, and with a signaling device with the aid of which the warning signal can be reproduced in a way that is perceptible to a driver.

[0006] FR 2 965 513 A1 discloses a device comprising a reflection unit arranged relative to a rod-shaped drawbar of a towed vehicle for reflecting a pair of telemetry signals toward a telemetry unit. The reflection unit is arranged symmetrically on two sides of a longitudinal center plane of a towing vehicle. To support the reflection unit, a support unit is arranged and fastened to the drawbar. The support unit comprises a central section fastened to the drawbar and end sections located on two sides of the central section. Also disclosed is an arrangement for determining the angular position of a towed vehicle relative to a towing vehicle, which arrangement comprises a telemetry unit.

[0007] DE 10 2012 006 206 A1 discloses that to detect an impending collision between a towing vehicle and its trailer, the position of the trailer relative to the towing vehicle is recorded. The impending collision is detected based on this recorded position.

[0008] The object of the following invention is to provide a method, a driver assistance system and a motor vehicle by means of which a critical situation between the motor vehicle and a trailer attached to the motor vehicle can be reliably prevented.

[0009] This object is achieved by a method, a driver assistance system and a motor vehicle according to the independent claims.

[0010] One aspect of the invention relates to a method for preventing a critical situation involving a combination comprising a motor vehicle and a trailer attached to it. The shape of an area of ​​the motor vehicle facing the trailer is detected. The shape of an area of ​​the trailer facing the motor vehicle is detected.

[0011] According to the invention, at least one first characteristic point in the area of ​​the motor vehicle is determined at which point the motor vehicle would contact the trailer in the critical situation. At least one second characteristic point in the area of ​​the trailer is determined at which point the trailer would contact the motor vehicle in the critical situation. A distance between the first characteristic point and the second characteristic point while the motor vehicle is driving is determined. A speed of a change in distance between at least the first characteristic point (8) and the second characteristic point (9) is determined.Depending on the speed of the distance change, a control signal is generated for a functional unit of the motor vehicle and / or trailer when the determined distance between the first characteristic point and the second characteristic point falls below a predetermined distance threshold. A control signal is sent to the functional unit, and an operating state of the functional unit is set to prevent the critical situation.

[0012] This makes it possible to predict the critical situation based on the distance between the respective characteristic points and to generate the control signal depending on whether the detected distance falls below a distance threshold. This means that the critical situation can be detected and reliably prevented regardless of vibrations, even when the vehicle / trailer combination is traveling slowly. In particular, this makes it possible to determine not only the absolute distance but also the change in distance per unit of time, thus creating a further option for predicting and preventing critical situations between the motor vehicle and the trailer. In particular, if a predetermined speed threshold is exceeded, the critical situation can be detected at an early stage and appropriate countermeasures can be initiated automatically or manually by a driver of the vehicle / trailer combination.The speed of the respective distance changes can be determined in particular using the formulas:. D'L=DL+AvdDLdt D'R=DR+AvdDRdt be determined, where D' L and D' R the speeds between the respective characteristic points, D L and D R the distance thresholds for the left and right sides, viewed in the forward movement of the vehicle, and A v correspond to a freely selectable parameter.

[0013] Particularly when reversing, a so-called jackknife effect can occur, in which the trailer then touches the motor vehicle. This causes the trailer and the vehicle to buckle. In other words, the trailer buckles relative to the motor vehicle and could touch the motor vehicle with the second characteristic point at the first characteristic point.

[0014] By determining the distance, for example, if the predetermined distance threshold is undershot, the operating state of the vehicle during the jackknife can be adjusted or modified accordingly to prevent the critical situation. Continuous monitoring of the distance between the two characteristic points of the trailer and the vehicle can be carried out, so that the critical situation can be reliably prevented during driving, especially when reversing.

[0015] In particular, the shape of the area of ​​the motor vehicle can be detected using a detection device. Furthermore, the shape of the area of ​​the trailer can be detected using the same detection device. In other words, the one detection device can detect both the shape of the area on the motor vehicle and the shape of the area on the trailer. For example, a camera can function as the detection device, which then determines the characteristic point in the area of ​​the motor vehicle and in the area of ​​the trailer using an image processing program. The characteristic points can then also be determined by the detection device and, in particular, by the image processing program.

[0016] It is also possible for additional detection devices to determine the distance and / or the shape of the trailer area and the shape of the motor vehicle area. A combination of multiple detection devices is also possible. For example, one detection device can be arranged on the motor vehicle, a second can be arranged on the trailer. The detection devices can also be designed using different types of sensors. For example, one detection device can have a camera as a sensor and the additional detection device can have an ultrasonic sensor as a sensor. Other combinations of lidar sensors or radar sensors are also possible. In particular, the method can also be carried out while driving ahead, especially when the vehicle-trailer combination is maneuvering at low speed.

[0017] Preferably, the shape of the areas is determined anew each time, so that different trailer variants, in particular concerning the shape of the trailer, for example a cargo trailer, or a horse trailer or a boat trailer, can be detected and in particular the second characteristic point on the trailer can be newly determined in each case, so that for a large number of different trailers only one detection device is currently necessary in each case in order to prevent the critical situation between the motor vehicle and the trailer.

[0018] According to an advantageous embodiment, the control signal is sent to a braking system, which is a functional unit, of the motor vehicle and / or the trailer, and the vehicle combination is braked. In particular when reversing, the motor vehicle can be braked so that the critical situation, in particular the jackknife effect, can be prevented even more reliably because the motor vehicle cannot drive into the trailer due to the inertia of the trailer and the braking of the motor vehicle. It is also possible for the braking system of the trailer to be controlled; this has proven advantageous, particularly when driving ahead. It is also possible, if, for example, the motor vehicle and the trailer have a braking system, for the control signal to be sent to both braking systems, thus braking the vehicle combination.In particular, it is possible to send different control signals, so that, for example, the braking force is different for the motor vehicle than for the trailer. In particular, it is possible to distribute the braking forces in proportion to the respective weights of the motor vehicle and the trailer. This can also lead to a more reliable and improved prevention of the critical situation.

[0019] It has also proven advantageous if the method is carried out while the vehicle combination is moving backwards. The jackknife effect can occur particularly during reverse movement of the vehicle combination. This jackknife effect can lead to the motor vehicle and trailer getting into a critical situation. In particular, when reversing the vehicle combination into a parking space, this can cause a critical situation to arise between the vehicle and trailer. By applying the method while the vehicle combination is moving backwards, the critical situation can also be advantageously avoided, for example, when reversing the vehicle with the trailer into a parking space.

[0020] It has further proven advantageous to detect a third characteristic point on the motor vehicle and a fourth characteristic point on the trailer, and to generate the control signal depending on a distance between the first characteristic point and the second characteristic point and / or depending on the distance between the third characteristic point and the fourth characteristic point. In particular, this makes it possible to redundantly check whether a critical situation would arise between the motor vehicle and the trailer. In particular, the two distances between the four characteristic points can then be used, for example, to check whether a critical situation would actually arise. In particular, this makes it possible to redundantly predict the critical situation reliably and safely.

[0021] It is also advantageous if the third characteristic point and the fourth characteristic point are detected on a second side, wherein the second side lies opposite a first side which has the first characteristic point and the second characteristic point, and wherein the first side and the second side are separated by a longitudinal axis of the motor vehicle. In particular, the characteristic points at which the trailer and the motor vehicle would touch on the respective side when moving backwards can be determined both on a left side of the motor vehicle and on a right side of the motor vehicle, as viewed from the motor vehicle in front, or of the trailer.In particular, this makes it possible to determine the corresponding characteristic points for both sides, in other words when the trailer bends to the left or when the trailer bends to the right during reversing, and by determining the distances between the two contact points, the distances can be determined for both buckling options during reversing and it can be concluded whether or not a critical situation could arise between the motor vehicle and the trailer.

[0022] According to a further advantageous embodiment, the control signal for the functional unit can be generated when a difference between a larger of the two distances and a smaller of the two distances exceeds a threshold value. In particular, this can create a further possibility for checking whether a critical situation could arise between the motor vehicle and the trailer. This can provide a differential method by means of which the distance between the first characteristic point and the second characteristic point can be determined with a higher resolution. This makes it possible to predict the occurrence of the critical situation even more reliably and to control the functional unit, in particular a braking system, accordingly.

[0023] It has also proven advantageous if the control signal is sent to a warning device as a functional unit, and the warning device generates a warning signal for the driver of the vehicle / trailer combination. In particular, this allows the driver to be warned in advance of an automatically initiated braking of the vehicle or, if, for example, no automatic braking system is available, the driver can initiate the braking process manually when the warning signal is generated. For example, an acoustic, haptic, and / or visual warning signal can be generated for the driver to perceive.

[0024] A further aspect of the invention relates to a driver assistance system which is designed to carry out a previously described method or an advantageous embodiment thereof.

[0025] Yet another aspect of the invention relates to a motor vehicle with a driver assistance system. The motor vehicle is designed, in particular, as a passenger car.

[0026] Advantageous embodiments of the method are to be regarded as advantageous embodiments of the driver assistance system and the motor vehicle. The driver assistance system and the motor vehicle have specific features that enable implementation of the method or an advantageous embodiment thereof.

[0027] Further features of the invention emerge from the claims, the figures and the description of the figures. The features and combinations of features mentioned above in the description as well as the features and combinations of features mentioned below in the description of the figures and / or shown alone in the figures can be used not only in the respective combination specified, but also in other combinations and on their own, without departing from the scope of the invention. Thus, embodiments are to be regarded as encompassed and disclosed by the invention that are not explicitly shown and explained in the figures, but which arise from separate combinations of features from the explained embodiments and can be produced. Embodiments and combinations of features are also to be regarded as disclosed that therefore do not have all the features of an originally formulated claim.Furthermore, embodiments and combinations of features, in particular by the embodiments set out above, are to be regarded as disclosed which go beyond or deviate from the combinations of features set out in the claims.

[0028] Examples of embodiments are explained below using schematic drawings.

[0029] Showing: Fig. 1 a schematic plan view of a vehicle combination with an embodiment of a driver assistance system according to the invention; and Fig. 2 a further schematic plan view of a plurality of different combinations, each of which has an embodiment of a driver assistance system according to the invention.

[0030] In the figures, identical or functionally identical elements are provided with the same reference numerals.

[0031] Fig. Figure 1 shows a schematic plan view of a motor vehicle 1 with a trailer 2 attached, which, when coupled together, form a combination 3. Motor vehicle 1 is designed, in particular, as a passenger car. Motor vehicle 1 functions as the tractor unit of the combination 3. It is also possible for motor vehicle 1 to be designed, for example, as a truck or mobile home.

[0032] The motor vehicle 1 has a longitudinal axis L. The trailer 2 is coupled to the motor vehicle 1 via a trailer coupling 4. The motor vehicle 1 further has a detection device 5, by means of which a shape of an area 6 of the motor vehicle 1 that faces the trailer 2 is detected. By means of the detection device 5, a shape of an area 7 of the trailer 2 that faces the motor vehicle 1 can also be detected. It is possible for both the area 6 and the area 7 to be detected with the detection direction 5. It is also possible, for example, for at least one further detection device to be provided on the motor vehicle 1 and / or on the trailer 2, which can detect the areas 6, 7. The detection direction 5 can in particular be designed as a camera and can detect the corresponding areas 6, 7, for example, using an image processing program.It is also possible for the detection device 5 to be designed as a lidar sensor, radar sensor, or ultrasonic sensor and to detect areas 6, 7 accordingly. Any combination of the different sensor types is also possible to detect areas 6, 7. It is also possible for the detection device 5 or the additional detection device to be arranged on the trailer 2.

[0033] By means of the detection device 5, a first characteristic point 8 in the area 6 of the motor vehicle 1 can be determined, at which point the motor vehicle 1 would touch the trailer 2 in the critical situation. Furthermore, by means of the detection device 5, a second characteristic point 9 can be detected in the area 7, at which point the trailer 2 would touch the motor vehicle 1 in the critical situation. Furthermore, it can be provided that by means of the detection device 5, a third characteristic point 10 is determined in the area 6 of the motor vehicle 1, at which point the motor vehicle 1 would touch the trailer 2 in a further critical situation. It is also possible for the detection device 5 to detect a fourth characteristic point 11, which is in the area 7 of the trailer 2 and which the trailer 2 would touch the motor vehicle 1 in the critical situation.In particular, the critical situation can be a so-called jackknife effect, in which a critical situation could occur on both sides, viewed from the longitudinal axis L. In the jackknife effect, the trailer combination 3 collapses. In other words, the trailer 2 moves relative to the motor vehicle 1, so that the motor vehicle 1 and the trailer 2 can come into contact. In particular, it is provided that the third characteristic point 10 and the fourth characteristic point 11 are formed on a second side, wherein the second side is opposite a first side, and wherein the first side and the second side are separated from one another by the longitudinal axis L. By means of the detection device 5, a distance D L between the first characteristic point 8 and the second characteristic point 9. By means of the detection direction 5, a further distance D Rbetween the further first characteristic point 10 and the further second characteristic point 11.

[0034] The recording of distances D L , D R occurs, in particular, when the motor vehicle 1 is being driven with the attached trailer 2. In particular, the vehicle combination 3 is moving backward. In particular, during this backward movement, the jackknife effect can occur due to buckling, in which the motor vehicle 1 would touch the trailer 2.

[0035] The detection device 5 is coupled in particular to a driver assistance system 12 of the motor vehicle 1. A control signal for a functional unit 13 of the motor vehicle 1 is generated, for example by the driver assistance system 12, as soon as one of the distances D L , D Rfalls below a predetermined distance threshold. It is also possible for the control signal to be sent to a functional unit 14 of the trailer. In particular, it is provided that the respective functional unit 13, 14 is designed to adjust the operating state of the trailer combination 3 so that the critical situation between the motor vehicle 1 and the trailer 2 can be prevented. The functional unit 13 and / or the functional unit 14 can, for example, be a braking system, so that the trailer combination 3 is braked as soon as one or both functional units 13, 14 receive the control signal.

[0036] It is also possible that a control signal is sent to a warning device as a functional device 13, 14, and that the warning device generates a warning signal for a driver of the trailer 3.

[0037] It can further be provided that a speed of a change in distance between the first characteristic point 8 and the second characteristic point 9 as well as the third characteristic point 10 and the fourth characteristic point 11 is determined and a control signal for the functional unit 13, 14 is generated depending on the speed of the change in distance.

[0038] It is also possible that a difference between a larger of the two distances D L , D R and a smaller of the two distances D L , D R exceeds a threshold value and after the threshold value has been exceeded, the control signal is sent to the functional unit 13, 14. In particular, this can be used to achieve a differential change in the distances D L , D Rcan be determined and thus the critical situation between the motor vehicle 1 and the trailer 2 can be predicted with a higher resolution.

[0039] Fig. 2 shows a further schematic plan view of several teams 3. In the Fig.2, in particular, different variants of trailers 2 are attached to the motor vehicle 1. In particular, the different design of the shapes of the trailer 2 results in different first and second characteristic points 8, 9, 10, 11, at which the motor vehicle 1 would come into contact with the respective trailer 2 and the critical situation would occur. This makes it possible for the detection device 5, in particular in the area 7, to individually determine the shape of the trailer 2 and thereby individually determine the characteristic points 8, 9, 10, 11 for both the trailer 2 and the motor vehicle 1 in the individual attachment situation. This makes it possible to reliably predict the critical situation for the individual combination 3 and prevent it accordingly. In particular, this makes it possible to individually determine the distances D L , D Rthe characteristic points 8, 9, 10, 11 can be determined and thus a critical situation between the motor vehicle 1 and the trailer 2 can be prevented in the case of different combination variations.

Claims

[1] Method for preventing a critical situation of a combination (3) comprising a motor vehicle (1) and a trailer (2) attached thereto, comprising the steps: - detecting a shape of an area (6) of the motor vehicle (1) facing the trailer (2); - detecting a shape of an area (7) of the trailer (2) facing the motor vehicle (1); characterized by the steps: - determining at least one first characteristic point (8) in the area (6) of the motor vehicle (1) at which the motor vehicle (1) would touch the trailer (2) in the critical situation; - determining at least one second characteristic point (9) in the area (7) of the trailer (2) at which, in the critical situation, the trailer (2) would touch the motor vehicle (1); - Determine a distance (D L) between the first characteristic point (8) and the second characteristic point (9) during driving of the motor vehicle (1); - generating a control signal for a functional unit (13, 14) of the motor vehicle (1) and / or the trailer (2) when the determined distance (D L ) between the first characteristic point (8) and the second characteristic point (9); and - Sending the control signal to the functional unit (13, 14) and setting an operating state of the functional unit (13, 14) to prevent the critical situation, wherein a speed of a change in distance between at least the first characteristic point (8) and the second characteristic point (9) is determined and a control signal for the functional unit (13, 14) is generated depending on the speed of the change in distance. [2] Method according to claim 1, characterized by that the control signal is sent to a braking system, which is a functional unit (13, 14), of the motor vehicle (1) and / or the trailer (2) and the combination (3) is braked. [3] Method according to one of the preceding claims, characterized by that the procedure is carried out when the trailer (3) moves backwards. [4] Method according to one of the preceding claims, characterized by that a third characteristic point (10) on the motor vehicle (2) and a fourth characteristic point (11) on the trailer (2) are detected, and depending on a distance (D L ) between the first characteristic point (8) and the second characteristic point (9) and / or depending on the distance (D R ) between the third characteristic point (10) and the fourth characteristic point (11) the control signal is generated. [5] Method according to claim 4, characterized byin that the third characteristic point (10) and the fourth characteristic point (11) are detected on a second side, wherein the second side is opposite a first side which has the first characteristic point (8) and the second characteristic point (9), and wherein the first side and the second side are separated by a longitudinal axis (L) of the motor vehicle (1). [6] Method according to claim 4 or 5, characterized by that if there is a difference between a larger of the two distances (D L , D R ) and a smaller of the two distances (D L , D R ) exceeds a threshold value, the control signal for the functional unit (13, 14) is generated. [7] Method according to one of the preceding claims, characterized bythat the control signal is sent to a warning device as a functional device (13, 14), and a warning signal for a driver of the trailer (3) is generated by the warning device. [8] Driver assistance system (12) which is designed to carry out a method according to one of claims 1 to 7. [9] Motor vehicle (1) with a driver assistance system (12) according to claim 8.

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