DE102017201838A1 - Detection of road bumps using a situation analysis - Google Patents

Abstract

The invention relates to a speed adjustment device (100) for a vehicle. This has a detector arrangement (110), which is designed to detect a vertical position change of a preceding vehicle, and a control device (120), wherein the vertical position change of the preceding vehicle is caused by a ridden road surface unevenness. The controller (120) is implemented when the vertical position change of the preceding vehicle exceeds a predefined threshold and occurs within a predefined period of time to infer significant roadway fuzziness and for this reason reduce the speed of the vehicle.

Description

The invention relates to a speed adjustment device for a vehicle, a vehicle having a speed adjustment device, a method, a program element and a computer-readable medium.

Since the beginning of the development of motor vehicles, the comfort for the passengers is an important criterion. Some important milestones here are air suspension, parking assistant and cruise control. Especially in the last 10 years, numerous other active comfort features for vehicles have been developed. Road bumps can be present in the form of potholes, as well as in the form of a deliberately mounted speed threshold. Due to the bumps in the road, the comfort of the passengers can be impaired and the resulting mechanical stresses can lead to a reduced service life of the vehicle. The effect of roadway unevenness on the vehicle structure and comfort can be influenced inter alia by the speed with which the road bumpiness is run over.

It is the object of the invention to increase the longevity of vehicles and the comfort of their occupants.

This object is solved by the features of the independent claims. Further developments of the invention will become apparent from the dependent claims and the following description of embodiments.

A first aspect of the invention relates to a speed adaptation device for a vehicle, which is integrated, for example, in a driver assistance system. This has a detector arrangement, which is designed to detect a vertical position change of a preceding vehicle, and a control unit. The vertical position change of the preceding vehicle is caused by a ridden road surface unevenness. The controller is implemented when the vertical position change of the preceding vehicle exceeds a predefined threshold value and occurs within a predefined period of time, to conclude a significant roadway unevenness and for this reason to reduce the speed of the vehicle.

Accordingly, the detector arrangement can be used for the detection of road bumps. This can search the road directly in front of the vehicle for bumps in the road. However, this can be particularly in poor visibility conditions such. Dark or wet conditions lead to detection problems. Furthermore, it is advantageous to estimate the effects of uneven road surface on one's own vehicle.

Another possibility of uneven road surfaces is to detect the unevenness of the road surface indirectly by the movement of a vehicle in front. The preceding vehicle can be continuously observed by the detector arrangement of the speed adjustment device. The individual images of the detector arrangement can be compared with each other.

A roadway unevenness typically leads to a vertical change in position of the vehicle body. These effects on the preceding vehicle can be detected by the detector arrangement. When comparing the images, attention can be paid to a vertical change in position of the preceding vehicle within a predefined period of time. When the speed adjustment device detects that a predefined threshold, such as 10cm, 15cm or 20cm, a vertical change in position of the preceding vehicle within a predefined time interval, e.g. 200ms or 300ms, can be concluded on a significant road bump. Also, the detector arrangement can better estimate the effect of the road bump on the own vehicle since the effect of the single road bump on the preceding vehicle can be observed. As a countermeasure to the road unevenness to increase the comfort for the passengers and the durability of the vehicle, the speed adjusting device can reduce the speed upon detection of a significant road surface unevenness.

The speed reduction may be triggered by an indication to the driver of the vehicle. Alternatively it can be provided that the speed reduction takes place automatically by the speed adjustment device. Also, the reduction in speed may be dependent on the nature of the roadway bumpiness, i. the stronger the expected effects of roadway roughness on the vehicle, the more the speed of the vehicle can be reduced.

As another embodiment, the speed adjusting device may provide that after passing the roadway unevenness, the original speed is restored. This can be particularly advantageous if the vehicle is provided with a cruise control device (cruise control). Ie the vehicle reduces the speed, because a significant Road bumpiness was detected and after passing this road bumps can be accelerated back to the speed set in cruise control.

An embodiment of the invention provides that the speed adjustment device is designed to determine the distance to the vehicle in front and to calculate therefrom the time at which the road surface unevenness is reached.

For the determination of the time of occurrence of the roadway unevenness or for the determination of the remaining distance up to the roadway unevenness it may be necessary to determine the distance between the own vehicle and the preceding vehicle. By determining the point in time or the distance, the speed adjustment device can reduce the speed to the required level by this point in time, so that the final speed is reached only when reaching the roadway unevenness.

As a further advantage of determining the distance between the own vehicle and the vehicle ahead, it can be mentioned that the evaluation of the individual images of the detector arrangement can be simplified by the distance data. In other words, the individual images can be corrected more easily by the distance data so as to more easily detect a vertical position change of the preceding vehicle. Furthermore, the speed of the preceding vehicle can be determined as a result of this, since the own speed is known and the change of the distance indicates a speed difference between the own vehicle and the preceding vehicle. Also, by determining the timing of the road bump, the speed adjusting device can raise the speed to the original speed after passing the road bump. Outliers in the detector data can be compensated by the controller by comparing the history of the individual images. Thus, only existing road bumps lead to a reduction in speed.

A further embodiment of the invention provides that the detector arrangement has a camera, preferably with an image processing, wherein the distance to the vehicle in front takes place by means of a radar or a lidar sensor.

As a cost-effective and reliable embodiment of the detector arrangement, a camera can be provided with a corresponding image processing. It is also possible to use several cameras together. For the determination of the distance between the own vehicle and the preceding vehicle a radar and / or a lidar sensor can be used. As a further embodiment, ultrasonic sensors and / or laser scanners for the distance detection can be used. A combination of several different sensor technologies is also provided. The speed adjustment device can also rely on existing sensors in the vehicle, so that the speed adjustment device can be integrated cost and with little space in a vehicle concept.

An embodiment of the invention provides that the speed adaptation device is designed to determine the distance to the vehicle in front by means of a stereo camera and image processing.

The distance to the vehicle ahead can also be measured by a stereo camera with appropriate image processing. That Two cameras are used with a defined distance from each other, which essentially have the same field of view. Due to the different perspectives of the two cameras, the depth can be determined by means of image analysis. As a result, space and costs can be saved. In addition, the flexibility is increased in a subsequent integration into a vehicle concept, since not every vehicle concept, a radar or a lidar sensor is provided.

An embodiment of the invention provides that the speed adjustment device is designed to adjust the settings of the springs and the dampers of the vehicle on detection of a significant road bump to compensate for the road surface unevenness.

In addition to reducing vehicle speed, the speed adjustment device can also adjust the vehicle's springs and dampers for roadway unevenness, thereby minimizing the effects of roadway roughness on passengers. If the springs and dampers can be adjusted according to the situation, the vehicle can be adapted to the specific road surface roughness. Among other things, this can lead to a gain in comfort or the speed does not have to be reduced so far.

An embodiment of the invention provides that the speed adjustment device is designed to reduce the speed of the Vehicle as soon as the road surface unevenness has passed.

Knowing when the road bumpiness reaches the vehicle, the vehicle can be accelerated back to the initial speed after passing this road bump. Above all, if the vehicle by a speed control device (cruise control) holds the speed, after the road bump again the driver's request can be met and continued at a higher speed.

Another aspect of the invention relates to a method for adjusting the speed of a vehicle. In a first step, the preceding vehicle can be detected, so that vertical position changes of the preceding vehicle can be detected. In a second step, the vertical position changes caused by road bumps can now be detected. In a subsequent step, the method may reduce the speed of the vehicle when the vertical position change of the preceding vehicle exceeds a predefined threshold and occurs within a predefined period of time such that the effect of roadway unevenness on the vehicle and its occupants is minimized. The individual steps of the method can also be carried out in different order or can also be carried out simultaneously.

Another aspect of this invention relates to a vehicle having a speed adjusting device described above and hereinafter.

The vehicle may be, for example, a motor vehicle, such as a car, bus or truck.

Another aspect of the present invention relates to a program element that, when executed by a controller of a vehicle, instructs the vehicle to perform the method described in the context of the present invention.

Another aspect of the present invention relates to a computer readable medium having stored thereon a computer program which, when executed by a controller, directs the controller to perform the method described in the context of the present invention.

• 1 zeigt eine schematische Darstellung einer Geschwindigkeitsanpassungsvorrichtung gemäß einer Ausführungsform der Erfindung.
• 2 zeigt eine schematische Darstellung einer vertikalen Positionsänderung eines Fahrzeugs in einzelnen Bildern.
• 3 zeigt eine schematische Darstellung eines Fahrzeugs mit einer Geschwindigkeitsanpassungsvorrichtung und einer Fahrbahnunebenheit.
• 4 zeigt eine schematische Darstellung eines Fahrzeugs mit einer Geschwindigkeitsanpassungsvorrichtung und eines vorausfahrenden Fahrzeugs, welches durch eine Fahrbahnunebenheit eine vertikale Positionsänderung erfährt.
• 5 zeigt ein Flussdiagramm für ein Verfahren zur Reduzierung der Geschwindigkeit bei Detektion von Fahrbahnunebenheiten.

Other features, advantages and applications of the invention will become apparent from the following description of the embodiments and figures. The figures are schematic and not to scale. If the same reference numerals are given in the following description in different figures, these designate the same or similar elements.

• 1 shows a schematic representation of a speed adjustment device according to an embodiment of the invention.
• 2 shows a schematic representation of a vertical change in position of a vehicle in individual images.
• 3 shows a schematic representation of a vehicle with a speed adjustment device and a road surface unevenness.
• 4 shows a schematic representation of a vehicle with a speed adjustment device and a preceding vehicle, which undergoes a vertical position change by a road surface unevenness.
• 5 shows a flowchart for a method for reducing the speed in detection of road bumps.

1 shows a vehicle 200 with a speed adjustment device 100 , The speed adjustment device 100 has a detector arrangement 110 , a control unit 120 and a distance measuring arrangement 130 on. Here is the detector arrangement 110 executed to recognize a preceding vehicle and record its vertical position changes (movements). Typically, the detector assembly 110 consist of one or more cameras. The control unit 120 is executed from the data of the detector array 110 to extract and evaluate the vertical position changes of the preceding vehicle. For the evaluation, the control unit can compare the images of the vehicle ahead with each other and thus detect the vertical position changes of the vehicle ahead. As soon as the control unit detects a vertical change in position of the vehicle in front which exceeds a predefined threshold value in the position change, for example 10 cm, 15 cm or 20 cm and within a predefined time interval, eg 200 ms or 300 ms, the control unit can 120 indicate a significant road surface roughness. These significant road bumps may be, for example, potholes or speed bumps. If such a significant roadway unevenness is detected by the control device, the control device can control the driver of the vehicle 200 instruct the speed of the vehicle 200 reduce the road surface unevenness to a lesser extent the vehicle 200 and his inmates. On the one hand, this reduces the mechanical load on the vehicle parts, thus reducing wear and, on the other hand, the comfort for the passengers of the vehicle 200 increase. According to one embodiment of the invention, the control device 120 also directly the vehicle 200 to reduce the speed, especially when the vehicle 200 has semi-automated or fully automated driving functions. By the distance measuring arrangement 130 can the distance between the vehicle 200 and the preceding vehicle. By determining the distance, the control unit 120 determine when the vehicle 200 reaches the road surface unevenness. Thus, a targeted reduction of the speed can be done until reaching the position of the road bump. Also, after passing the road bump, the vehicle 200 be accelerated back to its original speed. The distance measuring arrangement 130 Furthermore, it is also helpful for the detection of the vertical position changes of the preceding vehicle, since so the control unit 120 the images of the detector array 110 easier to change the distance between the vehicle 200 and correct the preceding vehicle. Also, with the help of the rangefinder 130 be closed to the speed of the vehicle ahead. On the one hand, one's own speed is known and, on the other hand, it is possible to deduce the speed of the vehicle ahead by means of the distance and the temporal change of the distance. The distance measuring arrangement 130 may for example consist of a radar, an ultrasonic or a lidar sensor. It is also conceivable, the distance measuring arrangement 130 to realize by a stereo camera with a corresponding image processing or a laser scanner. Furthermore, the control unit 120 based on the data of the detector array 110 the impact of road bumps on the vehicle 200 determine. Thus, the controller depending on the expected effects of the road bump on the vehicle 200 the speed of the vehicle 200 to reduce. According to a further embodiment of the invention, the control device 120 in addition to reducing the vehicle speed, also the settings of the springs and the dampers of the vehicle 200 adjust the impact of road bumps on the vehicle 200 lower. The speed adjustment device 100 can also be operated, for example, in the dark and / or wet, as the vehicle ahead is recognizable even in the dark by its lighting equipment. Also, the effects of roadway roughness on the own vehicle can be better estimated since the effects of roadway roughness on the preceding vehicle have been observed and thus known.

2 shows a schematic representation of a vehicle which undergoes a vertical position change by a road surface unevenness. For this purpose, the individual images of the detector arrangement are compared. In picture 1 the vehicle is at a starting position, which is symbolized by the upper dashed line. In picture 2 the vehicle is already below the starting position from picture 1 , Image n stands for an image larger than two and is intended to represent the time course of the vertical change in position of the vehicle. It can be seen that the vehicle continues to move down until image n is reached. This vertical position change of image 1 over picture 2 up to picture n suggests a roadway unevenness in the form of, for example, a pothole. Due to the temporal course of the change in position over the individual images of the detector arrangement can also be concluded on the duration of this change in position. In other words, in which time interval the vertical position change takes place and how big the position change is. The time interval in which the images are recorded is known and the resulting vertical position change can be determined by means of image evaluation. Thus, it can also be concluded that the road surface is uneven. The greater the vertical position change in a shorter time interval, the stronger the impact of the road surface roughness on the vehicle and its occupants.

3 shows a vehicle 200 with the speed adjustment device 100 on a road with a road surface unevenness. The road surface unevenness is indicated by the gray area in front of the vehicle. The road surface unevenness is difficult to detect by a camera system of the vehicle, especially in the dark or when wet. If the vehicle drives over the roadway unevenness, here a pothole, the roadway unevenness induces a vertical change in position into the vehicle.

4 shows a schematic representation of a vehicle 200 with the speed adjustment device 100 and a preceding vehicle. In 4 Two possibilities of a road bump are shown. On the one hand a pothole (upper part) and on the other a speed threshold (lower part). Due to the roadway unevenness, the rear of the vehicle in front is subjected to a vertical change in position. This will be in 4 represented by the little black arrows. This vertical change in position of the rear of the vehicle in front can be detected by the detector arrangement 110 the speed adjustment device 100 be taken and by the control unit 120 be evaluated. The distance measuring arrangement 130 can the distance between your own vehicle 200 and the preceding vehicle. Thus, it can be calculated when the road surface unevenness will reach or reach the own vehicle. In addition, based on the distance, the time or the Stecke can be determined, in which the speed of the vehicle 200 should be reduced. It is also possible to calculate how much retardation has to be made in order to maintain adequate speed until the road is uneven. As another aspect, after passing the roadway unevenness, the vehicle may 200 be accelerated back to its original speed.

5 shows a flowchart for a method for adjusting the speed of a vehicle. In step 501 a preceding vehicle is detected and observed by a detector arrangement. step 502 is used to detect a vertical position change of the preceding vehicle, wherein the vertical position change is caused by a road surface unevenness. In step 503 the speed of the vehicle is reduced when the vertical position change of the preceding vehicle exceeds a predefined threshold and occurs within a predefined period of time.

Claims (10)

A speed adjustment device (100) for a vehicle, comprising: a detector assembly (110) configured to detect a vertical position change of a preceding vehicle; and a controller (120); wherein the vertical position change of the preceding vehicle is caused by a ridden road surface unevenness; wherein the control unit (120) is executed when the vertical position change of the preceding vehicle exceeds a predefined threshold value and occurs within a predefined period of time, to conclude a significant roadway unevenness and for this reason to reduce the speed of the vehicle. Speed adjusting device (100) according to Claim 1 wherein the speed adjusting device (100) is adapted to determine the distance to the preceding vehicle and to calculate therefrom the time when the road surface unevenness is reached. Speed adjusting device (100) according to Claim 2 wherein the detector assembly (110) comprises a camera. Speed adjusting device (100) according to Claim 2 or 3 wherein the determination of the distance to the vehicle ahead by means of a radar or a lidar sensor (130) and / or by means of a stereo camera (110). A speed adjustment device (100) according to any one of the preceding claims, wherein the speed adjustment device (100) is adapted to adjust the settings of the springs and the dampers of the vehicle upon detection of significant roadway unevenness. A speed adjustment device (100) according to any one of the preceding claims, wherein the speed adjustment device (100) is adapted to increase the speed of the vehicle once the roadway unevenness has passed. Vehicle (200) with a speed adjustment device (100) according to one of the preceding claims. A method of adjusting the speed of a vehicle, comprising the steps of: - detecting (501) a preceding vehicle by a detector arrangement; - detecting (502) a vertical position change of the preceding vehicle, wherein the vertical position change is caused by a road surface unevenness; - Reducing (503) the speed of the vehicle when the vertical position change of the preceding vehicle exceeds a predefined threshold and occurs within a predefined period of time. A computer program element that, when executed on a control device of a vehicle, guides the vehicle, the method according to Claim 8 perform. Computer-readable storage medium on which the computer program element according to Claim 9 is stored.

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