Method for operating a control unit for a motor vehicle, corresponding control unit and computer program product

Abstract

The invention relates to a method for operating a control unit for a motor vehicle, wherein an obstacle parameter of an obstacle described by the environmental data is determined on the basis of environmental data detected by an environmental detection device of the motor vehicle.It is provided that the obstacle parameter is determined based on an obstacle contour of the obstacle by selecting geometry parameter data of a comparison geometry describing the obstacle contour in such a way that an image (3) of the obstacle described by the environmental data lies at least partially in the comparison geometry (5), and at least one geometry parameter contained in the geometry parameter data is adapted so that a comparison geometry value calculated from the geometry parameter data lies within a tolerance range determined on the basis of the environmental data and / or a distance between a point on the comparison geometry (5) and a point on the image (3) of the obstacle corresponds at most to a defined distance and / or a defined portion of the image (3) of the obstacle is included in the comparison geometry (5). The invention further relates to a control unit for a motor vehicle and to a computer program product.

Description

[0001] The invention relates to a method for operating a control unit for a motor vehicle, wherein an obstacle parameter of an obstacle described by the environmental data is determined based on environmental data acquired by an environmental detection device of the motor vehicle. The invention further relates to a control unit for a motor vehicle and a computer program product.

[0002] For example, the prior art document DE 10 2014 006 547 A1 is known. This describes a method for issuing a warning to a driver of a motor vehicle to avoid a collision of a wheel with an object, comprising the following steps: detecting an object by evaluating sensor data; performing object tracking during a movement of the motor vehicle; issuing a warning in the event of an impending collision with the object; wherein the warning is issued in the event of an impending collision of the inside of a wheel with the object.

[0003] Furthermore, DE 10 2021 209 136 A1 discloses a method for determining and characterizing road surface irregularities. For this purpose, sensor data is generated by at least one wheel speed sensor and / or at least one wheel-specific acceleration sensor of a motor vehicle traveling on the road. The road surface irregularities are determined and characterized by a computing device using the generated sensor data. In this process, an edge shape of the road surface irregularities is determined.

[0004] Finally, WO 2018 / 022409 A1 discloses a method for maneuvering a vehicle, comprising: receiving, by one or more processors of a perception system of the vehicle, sensor information identifying a set of objects and a set of features for each object in the set of objects; filtering, by the one or more processors, the set of objects to remove objects corresponding to vehicles, bicycles, and pedestrians; and selecting, by the one or more processors, an object from the identified set of objects within an expected future path of the vehicle.

[0005] Furthermore, according to the method, the following steps are provided: classifying the object as traversable or non-traversable based on the set of features by the one or more processors, wherein the classification as traversable indicates that the vehicle can drive over the object without causing damage to the vehicle; and maneuvering the vehicle based on the classification by the one or more processors such that maneuvering the vehicle includes driving the vehicle over the object by not changing the expected future path of the vehicle if the object is classified as traversable.

[0006] It is an object of the invention to propose a method for operating a control device for a motor vehicle, which has advantages over known methods, in particular enables a particularly reliable classification of the obstacle, preferably in order to provide effective overrun protection.

[0007] This is achieved according to the invention with a method for operating a control unit for a motor vehicle having the features of claim 1.It is provided that the obstacle parameter is determined on the basis of an obstacle contour of the obstacle by selecting geometry parameter data of a comparison geometry describing the obstacle contour in such a way that an image of the obstacle described by the environmental data lies at least partially in the comparison geometry, and at least one geometry parameter contained in the geometry parameter data is adapted so that a comparison geometry value calculated from the geometry parameter data lies in a tolerance range determined on the basis of the environmental data and / or a distance between a point on the comparison geometry and a point on the image of the obstacle corresponds at most to a defined distance and / or a defined portion of the image of the obstacle is included in the comparison geometry.

[0008] Advantageous embodiments with useful further developments of the invention are specified in the dependent claims. It should be noted that the exemplary embodiments explained in the description are not limiting; rather, any variations of the features disclosed in the description, the claims, and the figures are feasible.

[0009] The method serves to operate the control unit, which is preferably a component of the motor vehicle. Of course, the control unit can also be separate from the motor vehicle, in particular up to the point where the control unit is mounted on or in the motor vehicle. The control unit is supplied with the environmental data that is acquired using the environmental detection device of the motor vehicle. The environmental detection device serves to acquire an environment or surroundings of the motor vehicle using at least one sensor, preferably using a plurality of sensors. In particular, one or more of the following sensors are used as the sensor or sensors: radar sensor, ultrasonic sensor, laser sensor or laser scanner, lidar sensor, infrared sensor and image sensor or camera.

[0010] With the help of the environment detection device, the environment of the motor vehicle is reliably monitored so that one or more obstacles present in the environment are reflected in the environment data, i.e. are described or mapped by the environment data. Based on the environment data, the obstacle parameter that describes the obstacle is determined. The obstacle parameter is, for example, a collision risk. In this case, it is preferably provided to use the obstacle parameter, i.e. ultimately based on the environment data, to determine a collision risk, i.e. a probability with which the motor vehicle will collide with the obstacle if the current driving operation continues, in particular if the current direction of travel and / or the current lane and / or the current travel speed is maintained.

[0011] If there are multiple obstacles in the environment or if multiple obstacles are described or mapped by the environment data, the obstacle parameter is preferably determined for each of these obstacles. Where reference is made to the obstacle in this description, the explanations always represent at least one obstacle, i.e., precisely one obstacle or multiple obstacles. The explanations for the obstacle are transferable to the at least one obstacle or each of the multiple obstacles. Conversely, explanations given for multiple obstacles are also applicable to the obstacle, for example, a single obstacle.

[0012] For example, the motor vehicle has a driver assistance system that at least temporarily assumes longitudinal and / or lateral guidance of the motor vehicle. The driver assistance system preferably decelerates or brakes the motor vehicle when the obstacle is present, in particular when the determined collision risk exceeds a collision risk threshold, for example by appropriately controlling a braking system of the motor vehicle, in particular a service brake of the motor vehicle, and / or by controlling a drive system of the motor vehicle. Additionally or alternatively, the driver assistance system at least temporarily assumes lateral guidance, i.e., steering, of the motor vehicle.In this case, it can be provided that the driver assistant adjusts a steering angle of the motor vehicle depending on the obstacle parameter in such a way that a collision of the motor vehicle with the obstacle is avoided, in particular by steering the motor vehicle around the obstacle.

[0013] To implement such functionality in the driver assistance system, it is necessary to determine the obstacle parameter with high accuracy. It is advantageous to first determine the obstacle contour and then determine the obstacle parameter using the obstacle contour. This achieves a high degree of obstacle parameter accuracy. To determine the obstacle contour, the reference geometry for the obstacle is first defined by determining the geometry parameter data of the reference contour. The reference geometry forms the obstacle contour using the geometry parameter data, so that the obstacle parameter is ultimately determined from the geometry parameter data.

[0014] To determine the geometry parameter data, these are first defined such that the obstacle or its image contained in the surroundings data lies at least partially or completely in the comparison geometry, i.e. is recorded by the comparison geometry using the selected geometry parameter data. This means that the geometry parameter data are selected such that the comparison geometry is at least as large as the image of the obstacle, preferably in different directions, in particular in directions perpendicular to one another, so that it completely encloses it. For example, the geometry parameter data are selected such that the comparison geometry is larger than the image. The image is understood to mean, in particular, a two-dimensional image of the obstacle as it appears from the perspective of the motor vehicle and as recorded by the surroundings detection device.

[0015] The at least one geometry parameter is then adjusted in order to better adapt the comparison geometry to the representation of the obstacle. The geometry parameter is at least one parameter contained in the geometry parameter data. It can be provided that the geometry parameter data only comprises the geometry parameter, but preferably the geometry parameter is one of several geometry parameters contained in the geometry parameter data. Insofar as reference is made to the at least one geometry parameter or the geometry parameter within the scope of this description, the explanations are equivalent. Explanations regarding the at least one geometry parameter therefore apply to the geometry parameter and explanations regarding the geometry parameter apply to the at least one geometry parameter. Preferably, only a single geometry parameter is adjusted.However, it may also be provided that several geometry parameters are adjusted in the manner described in order to adapt the comparison geometry to the image of the obstacle with high accuracy.

[0016] The geometry parameter can be adjusted in different ways. In a first variant, the reference geometry value is determined from the geometry parameter data, and the tolerance range is determined from the surrounding data. The geometry parameter is then adjusted in such a way that the reference geometry value changes toward the tolerance range, at least if it lies outside the tolerance range. This occurs, in particular, until the reference geometry value lies within the tolerance range. It is then assumed that the reference geometry describes the obstacle with sufficient accuracy, i.e., represents the obstacle contour.

[0017] In a second variant, the distance between the location of the reference geometry and the location of the obstacle image is determined. If the distance is greater than the defined distance, the geometry parameter is adjusted, again in such a way that the distance changes in the direction of the defined distance. This preferably occurs until the distance equals or is smaller than the defined distance. In particular, the adjustment is terminated as soon as this condition is met.

[0018] In other words, the geometry parameter should be adjusted such that the distance between the location of the reference geometry and the location of the mapping corresponds at most to the defined distance, and is preferably smaller than this. For example, a location of the reference geometry is used as the location of the reference geometry for which a sum of absolute coordinate values ​​in mutually perpendicular directions is maximum—at least at the beginning of the adjustment or before the adjustment. In particular, the location closest to the location of the reference geometry is used as the location of the mapping.

[0019] According to a third variant, the portion of the obstacle or its image that lies within the reference geometry is determined. If this portion is less than or equal to the defined portion, it is assumed that the reference geometry represents the obstacle or its image sufficiently accurately. If the portion is greater than the defined portion, the geometry parameter is adjusted so that the portion changes in the direction of the defined portion. For example, the geometry parameter is adjusted until a certain point in the obstacle image lies outside the reference geometry.

[0020] Regardless of the type of geometry parameter adjustment, the obstacle parameter provides an accurate description of the obstacle. This is especially true because the obstacle parameter is determined based on a precisely defined obstacle contour, which describes the contour of the obstacle with a good approximation.

[0021] A further development of the invention provides that the comparison geometry is determined based on the geometry parameter data from two circular arcs, in particular symmetrically arranged circular arcs, and / or that at least one of the following geometry parameters is used as a component of the geometry parameter data: width, height, and radius. The comparison geometry describes the obstacle only approximately, but nevertheless in such a way that the obstacle parameter can be determined with high accuracy. Surprisingly, it has been found that this is the case if the comparison geometry is defined based on two circular arcs, which are preferably arranged symmetrically to one another, in particular axially symmetrically.

[0022] Preferably, the two circular arcs have at least the same radius. The circular arcs lie entirely on imaginary circles, a first of the circular arcs on a first of the circles and a second of the circular arcs on a second of the circles. If their radius is greater than or equal to the distance between their centers, the circular arcs touch at one point or intersect at two points. At least two tangents are drawn to the circles or the circular arcs, namely on opposite sides of the circular arcs. A first of the tangents lies tangentially to a first of the circular arcs and a second of the tangents lies tangentially to a second of the circular arcs. The tangents are perpendicular to a straight zero line which runs on a first axis of the coordinate system, in particular corresponding to the transverse axis of the motor vehicle.

[0023] If the radius of the circular arcs is smaller than the distance between their centers, or if twice the radius is less than or equal to a width of the reference geometry, the tangents lie on opposite sides of the circular arcs. The first tangent lies on the side opposite the second arc, and the second tangent lies on the side opposite the first arc, and the second tangent lies on the side opposite the first arc. The tangents each run outside the imaginary circles that define the circular arcs. In other words, the tangents lie on the circular arcs at a distance from an intersection formed by the imaginary circles.

[0024] However, if the radius of the arcs is greater than the distance between their centers, or if twice the radius is greater than the width of the reference geometry, the tangents each lie within one of the imaginary circles. Thus, the first tangent lies within the second circle, and the second tangent lies within the first circle. In other words, the tangents each directly border the intersection formed by the circles.

[0025] The two circular arcs intersect at a point of intersection. If this point of intersection lies below a highest point of the reference geometry, i.e. a corresponding coordinate value of the point of intersection is smaller than the height of the reference geometry, then another tangent exists that runs parallel to the zero line. This additional tangent lies on the side of the circular arcs facing away from the zero line and is only connected to the tangents described above via the circular arcs. This is particularly the case if twice the radius is less than or equal to the width of the reference geometry. The reference geometry is bounded by the zero line, the two tangents, the two circular arcs, and the additional tangent. The intersection point of the circles lies in the reference geometry.

[0026] If, on the other hand, twice the radius is larger than the width of the comparison geometry, the further tangent is omitted. In this case, the comparison geometry is bounded by the zero line, the two tangents, and the two circular arcs that converge at the point of intersection. The point of intersection therefore lies on an edge of the comparison geometry or forms it. In any case, a central axis of the comparison geometry runs through the point of intersection and is perpendicular to the zero line or an axis of the coordinate system. The comparison geometry is preferably designed to be axially symmetrical with respect to the central axis. The central axis preferably passes through a zero point of the first axis, so x = 0 applies to it. For example, the image of the obstacle or the comparison geometry is shifted in such a way that this condition is met, i.e. the image and / or the comparison geometry is centered with respect to the zero point of the first axis.

[0027] The comparison geometry is defined by a plurality of geometry parameters, of which at least one geometry parameter is adapted in the manner described. Preferably, the comparison geometry is defined by all three of the aforementioned parameters, i.e., the width, the height, and the radius. Preferably, the width and height are specified, and then the radius is adjusted according to the procedure explained. For the comparison geometry determined from the two circular arcs, the centers of the circular arcs, for example, result from the width, height, and radius. In a first direction of a coordinate system, in particular in the transverse direction of the motor vehicle, the centers of the circular arcs, for example, result from the relationships x1 = - b / 2 + R and x2 = b / 2 - R, where b is the width of the comparison geometry and R is the radii of the circular arcs.In a second direction of the coordinate system, specifically in the vertical direction of the vehicle, the coordinates of the center points are determined based on the relationship y1 = y2 = h - R, where h is the height of the reference geometry. The center of the first circular arc is therefore located at (x1, y1), and the center of the second circular arc is located at (x2, y2). Using the described procedure, a good approximation of the obstacle representation using the reference geometry is achieved.

[0028] A further development of the invention provides that a data point cloud describing the obstacle and containing a plurality of data points is used as environmental data, wherein the data points contain first coordinate values ​​for a first direction of a coordinate system and second coordinate values ​​for a second direction of the coordinate system, and a first geometric parameter is determined from the first coordinate values ​​and a second geometric parameter from the second coordinate values. The environmental data is therefore present in the form of a data point cloud, which in turn contains a plurality of data points. Each data point is defined by two coordinate values, namely the first coordinate value for the first direction of the coordinate system and the second coordinate value for the second direction of the coordinate system. The first direction runs on a first axis and the second direction on a second axis of the coordinate system.

[0029] The coordinate system can in principle be defined arbitrarily; a Cartesian coordinate system is preferably used, so that the two directions or axes are perpendicular to one another. Preferably, the first direction corresponds to a transverse direction of the motor vehicle and the second direction to a vertical direction of the motor vehicle. The transverse direction and the vertical direction are perpendicular to one another and also each perpendicular to a longitudinal axis of the motor vehicle. A first of the geometric parameters, for example the width, is determined from the first coordinate values, and the second geometric parameter, for example the height, is determined from the second coordinate values. This achieves a high degree of agreement between the comparison geometry and the obstacle or its representation.

[0030] A further development of the invention provides that for different coordinate values ​​in the first direction the data points with the respective largest second coordinate values ​​are determined, a minimum value for the second coordinate values ​​is determined from these data points and the first geometry parameter is inferred from a maximum difference between the first coordinate values ​​of those data points whose second coordinate values ​​exceed the minimum value, and / or that the second geometry parameter is determined from a maximum value of the second coordinate values ​​of the data points.

[0031] First, a type of envelope of the data points is determined by retaining only the data point with the largest first coordinate value for data points that have identical second coordinate values. The smallest second coordinate value for the envelope is then searched for, in particular after filtering the data points in order to filter out data points caused by measurement errors. Next, all data points are evaluated that have a second coordinate value that is greater than the minimum value. For these data points, the smallest first coordinate value and the largest first coordinate value are determined. The difference between these two values ​​results in the first geometry parameter, in particular the width. Additionally or alternatively, the maximum value of the second coordinate values ​​of all data points or of the data points lying on the envelope is determined.The second geometric parameter is determined based on the maximum value, in particular, it is set equal to it. The second geometric parameter, in particular, is the height.

[0032] A further development of the invention provides that a third geometry parameter different from the first geometry parameter and the second geometry parameter is used as the geometry parameter. This ultimately means that the third geometry parameter different from the first geometry parameter and the second geometry parameter is used to adapt the comparison geometry to the representation of the obstacle. Preferably, the first geometry parameter and the second geometry parameter are kept constant during the adaptation of the third geometry parameter. This results in a fast and efficient determination of the obstacle contour and ultimately of the obstacle parameter.

[0033] A further development of the invention provides that an area of ​​the comparison geometry calculated from the geometry parameter data is used as the comparison geometry value, and / or that the geometry parameter is iteratively adjusted until the comparison geometry value lies within the tolerance range and / or the distance between the location of the comparison geometry and the location of the obstacle image corresponds at most to the defined distance and / or the defined portion of the obstacle image is included in the comparison geometry. In a first variant, the adjustment of the geometry parameter, in particular the third geometry parameter, is carried out based on the area. This is calculated for the geometry parameter, in particular for the geometry parameter defining the comparison geometry, and compared with the area determined based on the environmental data.

[0034] If the two surface areas differ sufficiently, the geometry parameter is adjusted. The geometry parameter is preferably adjusted iteratively, i.e., step by step. For example, the geometry parameter is changed by a defined value until at least one of the specified conditions is met. It may also be possible, for example, to calculate the distance between the reference geometry value and the tolerance range and to select the defined value applied to the reference geometry value based on this distance. In any case, a rapid adjustment of the reference geometry to the obstacle or the representation of the obstacle is achieved.

[0035] In a second variant, the adjustment is based on the distance. For this purpose, the location of the comparison geometry is used, which is selected to be identical for various geometry parameters. For example, the location is the location of the comparison geometry for which the sum of absolute coordinate values ​​across the comparison geometry is maximum. This is particularly the case at corners of the comparison geometry. For example, the location used for the mapping is the location that is closest to the location of the comparison geometry or has the shortest distance to it. The geometry parameter is adjusted in such a way that the distance between the locations decreases, in particular until the distance corresponds at most to the defined distance, in particular is smaller. As soon as the aforementioned condition is met, the adjustment is terminated.

[0036] According to a third variant, the geometry parameter is adjusted such that the portion of the image captured by the comparison geometry becomes smaller. For example, the geometry parameter is adjusted such that at least one of the data points of the image lies outside the comparison geometry. Alternatively, the adjustment is carried out until a defined number or a defined portion of the data points, and consequently the defined portion of the image, is located outside the comparison geometry. As soon as the condition is met, the adjustment is terminated. In any case, the described procedure achieves a comparison geometry that is sufficiently similar to the image of the obstacle for the purposes of driver assistance, in particular overrun protection.

[0037] A further development of the invention provides that the obstacle parameter is used as part of a plurality of obstacle parameters describing the obstacle, wherein a portion of the environmental data is used to determine each of the obstacle parameters. Ultimately, the obstacle is divided into a plurality of partial obstacles, wherein a respective obstacle parameter is determined for each of the partial obstacles according to the procedure explained. For each partial obstacle, a partial obstacle contour is thus determined by selecting geometry parameter data of a comparison geometry describing the partial obstacle contour in such a way that an image of the partial obstacle described by the environmental data lies at least partially in the comparison geometry, and at least one geometry parameter contained in the geometry parameter data is adapted so that one or more of the aforementioned conditions are met, preferably until this is the case.

[0038] For example, the number of partial obstacles is determined based on the second coordinate values ​​of the data points. In particular, if local maxima of the second coordinate values ​​are present that are at least a certain distance apart, i.e., between which there is at least a certain difference in the first coordinate values, the obstacle is divided into several partial obstacles. Preferably, a partial obstacle is evaluated for each local maximum, and the respective partial obstacle contour and the corresponding obstacle parameter for the partial obstacle are determined accordingly. By using the multiple partial obstacles, the obstacle is mapped with high accuracy.

[0039] A further development of the invention provides that the obstacle parameter is used to determine a collision risk of a collision between the motor vehicle and the obstacle and / or a collision effect of the collision between the motor vehicle and the obstacle, in particular verified using at least one sensor measurement value. The collision risk is determined even before the collision between the motor vehicle and the obstacle occurs, namely using the obstacle parameter. For example, the obstacle parameter is used to implement overrun protection for the motor vehicle, so that the obstacle parameter or the collision risk is greater the larger the comparison geometry, in particular in the direction of the vertical axis of the motor vehicle.

[0040] If a height of the comparison geometry reaches or exceeds a certain threshold, it is assumed that the obstacle will come into contact with a substructure of the motor vehicle, for example an underbody of the motor vehicle, provided the motor vehicle drives over the obstacle. If the collision risk reaches or exceeds the threshold, it can be provided to warn the driver of the impending collision, in particular by means of a visual, acoustic and / or haptic signal, or to automatically carry out longitudinal and / or lateral guidance of the motor vehicle, i.e. with the help of a driver assistance device. The longitudinal and / or lateral guidance of the motor vehicle is preferably carried out in such a way that the collision of the motor vehicle with the obstacle is avoided.

[0041] Additionally or alternatively, it may be provided to determine the collision impact of the collision with the obstacle. The collision impact is determined, for example, only after a collision between the motor vehicle and the obstacle has occurred or is assumed. The collision impact describes, for example, the extent of damage to the motor vehicle due to the collision. The determined collision impact is preferably verified using the at least one sensor measurement value. The sensor measurement value is, for example, a measurement value from an acceleration sensor, a deformation sensor, or the like. In particular, the sensor is located on an underbody of the motor vehicle. If the collision is detected using the sensor, the previously determined collision impact is verified using the sensor measurement value.Additionally or alternatively, the sensor measurement value is included in the collision impact, i.e. it is taken into account in addition to the obstacle parameter when determining it.

[0042] The determined collision impact is preferably displayed to the driver of the motor vehicle, particularly in the form of a request to visit a workshop. However, it can also be provided that the driving operation of the motor vehicle is adjusted based on the collision impact. For example, if the collision impact exceeds a threshold, the motor vehicle's drive power is restricted or the motor vehicle is shut down to prevent consequential damage, particularly if the collision occurred in the area of ​​an electrical energy storage device of the motor vehicle.

[0043] The invention further relates to a control unit for a motor vehicle, in particular for carrying out the method according to the explanations in the context of this description, wherein the control unit is provided and designed to determine an obstacle parameter of an obstacle described by the environmental data on the basis of environmental data recorded by means of an environmental detection device of the motor vehicle.The control unit is further provided and designed to determine the obstacle parameter based on an obstacle contour of the obstacle by selecting geometry parameter data of a comparison geometry describing the obstacle contour in such a way that an image of the obstacle described by the environmental data lies at least partially in the comparison geometry, and at least one geometry parameter contained in the geometry parameter data is adapted so that a comparison geometry value calculated from the geometry parameter data lies in a tolerance range determined on the basis of the environmental data and / or a distance between a point on the comparison geometry and a point on the image of the obstacle corresponds at most to a defined distance and / or a defined portion of the image of the obstacle is included in the comparison geometry.

[0044] The advantages of such a control unit design and such a procedure have already been pointed out. Both the control unit and the method for its operation can be further developed according to the explanations in this description, so reference is made to these in this regard.

[0045] The invention also relates to a computer program product comprising instructions that cause the control unit to execute the described method according to the embodiments of this description. Regarding the advantages and possible advantageous developments, reference is made to the entire description.

[0046] The features and feature combinations described in the description, in particular the features and feature combinations described in the following description of the figures and / or shown in the figures, can be used not only in the respective combination specified, but also in other combinations or on their own, without departing from the scope of the invention. Thus, embodiments are also considered to be encompassed by the invention that are not explicitly shown or explained in the description and / or the figures, but which follow from or can be derived from the explained embodiments.

[0047] The invention will be explained in more detail below with reference to the exemplary embodiments shown in the drawings, without limiting the invention. In the drawings: Fig. 1 a schematic representation of environmental data which were recorded by means of an environmental detection device of a motor vehicle and describe an obstacle present in the environment of the motor vehicle, Fig. 2 a schematic representation of a process for determining a comparison geometry describing a contour of the obstacle, Fig. 3 a schematic representation of the comparison geometry with first geometry parameter data, as well as Fig. 4 a schematic representation of the comparison geometry for second geometry parameter data different from the first geometry parameter data.

[0048] The Fig. Figure 1 shows a schematic representation of environmental data 1 that was recorded by an environmental detection device of a motor vehicle. The environmental data 1 comprises a data point cloud with several data points 2, of which only a very small portion is marked as an example. The data points 2 contain a Fig. of an obstacle in the surroundings of the motor vehicle. The figure represents a two-dimensional representation of the obstacle as detected by the surroundings detection device. The data points 2 are in a Cartesian coordinate system, with a first direction x corresponding to a transverse direction of the motor vehicle and a second direction y corresponding to a vertical direction of the motor vehicle.

[0049] In the example shown here, data points 2 are located on both sides of a zero point in the first direction x; thus, the first coordinate values ​​of data points 2 for the first direction x have different signs. In particular, the first coordinate values ​​of the data points are adjusted, in particular shifted, such that they are centered relative to x = 0. Second coordinate values ​​of data points 2, which describe the second direction y, are consistently greater than or equal to 0. The envelope curve 4 plots the largest second coordinate value for each of the first coordinate values ​​occurring in data points 2.

[0050] Thus, for different coordinate values ​​in the first direction x, the data points 2 with the largest second coordinate values ​​for the second direction y are determined and plotted in the form of the envelope curve 4. From these data points, a minimum value for the second coordinate values ​​is determined. Subsequently, those data points 2 are selected for which the respective second coordinate value is greater than this minimum value. The maximum difference between the first coordinate values ​​of the second data points 2 results in a width b of the obstacle or its Fig. . A height h of the obstacle or the Fig. is determined from a maximum value of the second coordinate values. The width b and the height h are geometric parameters of a comparison geometry 5 (not shown here), with which the obstacle or the Fig. should be described in a simplified manner.

[0051] The Fig. 2 shows a schematic representation of a procedure for determining the comparison geometry 5. Shown is purely an example of the Fig. of the obstacle and the reference geometry 5 for different geometry parameters. The width b and height h of the reference geometry 5 are always chosen to be identical. A third geometry parameter, namely a radius R, is adjusted starting from an initial value, for example, this is equal to 0 mm or at least infinitesimally small. The adjustment of the geometry parameter is performed iteratively, resulting in numerous different reference geometries 5.

[0052] The adjustment of the geometry parameter is carried out until a distance between a point 6 of the comparison geometry 5, in this case two points 6, to a respective specific point of the Fig. is smaller than a defined distance. The specific location 6 is, for example, a location on a circular arc 7 of the comparison geometry 5 at a specific angle. Due to the adjustment of the geometry parameter, the comparison geometry 5 changes according to the arrow 16 until a shape is obtained which is as close as possible to the Fig. of the obstacle.

[0053] The Fig. Figure 3 shows a schematic representation of the comparison geometry 5 for first geometry parameter data, which contains the aforementioned geometry parameters, i.e., the width b, the height h, and the radius R. It can be seen that the comparison geometry 5 is composed of at least two circular arcs 7, which lie on congruent circles, i.e., have the same radius. A first of the circular arcs 7 has a first center point 8, and a second of the circular arcs 7 has a second center point 9.

[0054] For the geometry parameter data shown, the distance between the centers 8 and 9 is less than half the width b, which is ultimately determined by the distance between the centers 8 and 9 plus twice the radius R. This means that the circles on which the circular arcs 7 lie intersect at two intersection points 10 and 11.

[0055] In order to obtain a continuously closed comparison geometry 5, tangents 12 and 13 are applied to the circular arcs 7, which are perpendicular to a zero line 14 of the coordinate system. In addition, a tangent 15 is applied to the circular arcs 7, which runs parallel to the zero line 14 and rests against the circular arcs 7 on the side of the circular arcs 7 facing away from the zero line 14. The comparison geometry 5 is bounded by the zero line 14, the tangents 12 and 13, each starting from the zero line 14 up to the respective circular arcs 7, the circular arcs 7 between the respective tangent 12 or 13 on the one hand and the tangent 15 on the other, and the tangent 15 in its area lying between the circular arcs 7.

[0056] The Fig. Figure 4 shows the comparison geometry 5 for the second geometry parameter data, where the width b and the height h are identical to the first geometry parameter data. In contrast to the first geometry parameter data, the radius R is larger, in particular, it is larger than half the width b. In comparison to the comparison geometry 5 for the first geometry parameter data, the tangent 15 is omitted, since the circular arcs 7 intersect at a second coordinate value, which corresponds to the height H of the Fig. As already described, the comparison geometry 5 consists of the zero line 14, the tangents 12 and 13, and the circular arcs 7, whereas the tangent 15 is omitted.

[0057] With such a definition of the comparison geometry 5, different obstacles can be reliably approximated, allowing an obstacle contour to be easily determined from the data points 2 or the data point cloud. From this, an obstacle parameter describing the obstacle can be reliably determined, and based on this obstacle parameter, for example, an effective underrun protection system for the vehicle can be implemented. LIST OF REFERENCE SYMBOLS: 1 Environmental data 2 data points 3 Figure 4 Envelope 5 Comparison geometry 6 positions 7 circular arcs 8 Center 9 Center 10 Intersection 11 Intersection 12 Tangent 13 Tangent 14 Zero line 15 Tangent 16 Arrow QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] DE 10 2014 006 547 A1

[0002] DE 10 2021 209 136 A1

[0003] WO 2018 / 022409 A1

[0004]

Claims

[1] Method for operating a control device for a motor vehicle, wherein an obstacle parameter of an obstacle described by the environmental data is determined on the basis of environmental data recorded by an environmental detection device of the motor vehicle, characterized bythat the obstacle parameter is determined on the basis of an obstacle contour of the obstacle, in that geometry parameter data of a comparison geometry describing the obstacle contour are selected in such a way that an image (3) of the obstacle described by the environmental data lies at least partially in the comparison geometry (5), and at least one geometry parameter contained in the geometry parameter data is adapted so that a comparison geometry value calculated from the geometry parameter data lies in a tolerance range determined on the basis of the environmental data and / or a distance between a point on the comparison geometry (5) and a point on the image (3) of the obstacle corresponds at most to a defined distance and / or a defined portion of the image (3) of the obstacle is included in the comparison geometry (5). [2] Method according to claim 1, characterized bythat the comparison geometry (5) is determined on the basis of the geometry parameter data from two circular arcs (7), and / or that at least one of the following geometry parameters is used as a component of the geometry parameter data: width, height and radius. [3] Method according to one of the preceding claims, characterized by that a data point cloud describing the obstacle and containing a plurality of data points (2) is used as environmental data, wherein the data points (2) contain first coordinate values ​​for a first direction of a coordinate system and second coordinate values ​​for a second direction of the coordinate system and a first geometry parameter is determined from the first coordinate values ​​and a second geometry parameter is determined from the second coordinate values. [4] Method according to one of the preceding claims, characterized bythat for different coordinate values ​​in the first direction the data points (2) with the respective largest second coordinate values ​​are determined, a minimum value for the second coordinate values ​​is determined from these data points (2) and the first geometry parameter is inferred from a maximum difference between the first coordinate values ​​of those data points (2) whose second coordinate values ​​exceed the minimum value, and / or that the second geometry parameter is determined from a maximum value of the second coordinate values ​​of the data points (2). [5] Method according to one of the preceding claims, characterized by that a third geometry parameter different from the first geometry parameter and the second geometry parameter is used as the geometry parameter. [6] Method according to one of the preceding claims, characterized bythat an area of ​​the comparison geometry (5) calculated from the geometry parameter data is used as the comparison geometry value, and / or that the geometry parameter is adjusted iteratively until the comparison geometry value lies within the tolerance range and / or the distance between the location of the comparison geometry (5) and the location of the image (3) of the obstacle corresponds at most to the defined distance and / or the defined portion of the image (3) of the obstacle is included in the comparison geometry (5). [7] Method according to one of the preceding claims, characterized by that the obstacle parameter is used as part of several obstacle parameters describing the obstacle, whereby a part of the environmental data is used to determine each of the obstacle parameters. [8] Method according to one of the preceding claims, characterized bythat a collision risk of a collision between the motor vehicle and the obstacle and / or a collision effect of the collision between the motor vehicle and the obstacle are determined from the obstacle parameter. [9] Control unit for a motor vehicle, in particular for carrying out the method according to one or more of the preceding claims, wherein the control unit is provided and designed to determine an obstacle parameter of an obstacle described by the environmental data on the basis of environmental data recorded by an environmental detection device of the motor vehicle, characterized bythat the control unit is further provided and designed to determine the obstacle parameter based on an obstacle contour of the obstacle, in that geometry parameter data of a comparison geometry (5) describing the obstacle contour are selected in such a way that an image (3) of the obstacle described by the environmental data lies at least partially in the comparison geometry (5), and at least one geometry parameter contained in the geometry parameter data is adapted so that a comparison geometry value calculated from the geometry parameter data lies in a tolerance range determined on the basis of the environmental data and / or a distance between a point on the comparison geometry (5) and a point on the image (3) of the obstacle corresponds at most to a defined distance and / or a defined portion of the image (3) of the obstacle is included in the comparison geometry (5). [10] Computer program product comprising instructions which cause the control device according to claim 9 to carry out the method according to one or more of claims 1 to 8.

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