Determining a discrete representation of a roadway segment in front of a vehicle

Abstract

Device (16) for determining a discrete representation (30) of a roadway section in front of a vehicle (12), comprising: an input interface (22) for receiving sensor data (20) from a sensor (14) with information about the road section in front of the vehicle; a setting unit (24) for determining a control distance at which a property of the road section in front of the vehicle relevant for controlling the vehicle changes, based on the sensor data, and for setting a control point in a discrete representation of the road section corresponding to the control distance, wherein the setting unit is configured to set a smaller predefined second number (n2) of control points based on a predefined first number (n1) of control points; and an output interface (26) for outputting the smaller predefined second number (n2) of support points to an optimizer (52) for determining a profile of at least one control parameter for controlling a vehicle function based on the second number (n2) of support points, characterized by the fact that the setting unit (24) is configured to set another support point in the discrete representation (30) before and / or after a control distance at which the property relevant for controlling the vehicle (12) includes a discrete event, if further support points from the second number (n2) of support points can be set.

Description

[0001] The present invention relates to a device for determining a discrete representation of a road section in front of a vehicle. The present invention further relates to a corresponding method and system.

[0002] Modern vehicles (cars, vans, trucks, motorcycles, etc.) incorporate a multitude of systems that provide the driver with information and control individual vehicle functions partially or fully automatically. Sensors record the vehicle's surroundings and other road users. Based on the recorded data, a model of the vehicle's environment can be created, and changes in this environment can be responded to. Due to the ongoing development of autonomous and semi-autonomous vehicles, the influence and scope of such advanced driver assistance systems (ADAS) are becoming ever larger. The development of increasingly precise sensors makes it possible to record the environment and traffic and to control individual vehicle functions completely or partially without driver intervention.Driver assistance systems can particularly contribute to increasing road safety and improving driving comfort.

[0003] In addition to detecting and recognizing static objects in the vehicle's surroundings using environmental sensors such as cameras, radar, lidar, or ultrasonic sensors, moving objects and other road users can also be detected. Based on this, the behavior of an autonomous or semi-autonomous vehicle can be adapted to the current situation.

[0004] To control an autonomous and / or semi-autonomous vehicle, it is necessary to know several control parameters for a section of road ahead of the vehicle. This requires the evaluation of a large amount of data, which leads to a high computational effort, particularly due to the short time in which the control parameter must be determined. For example, it is known from DE 10 2015 116 877 A1, DE 10 2006 028 277 A1 or DE 101 14 412 C1 to model or scan and process the section of road ahead of a vehicle in discrete steps with a constant distance. With the number of steps, on the one hand, the time or length in front of the vehicle in which the future is looked into, i.e. in which the control parameter for future autonomous driving is known, increases. On the other hand, with each of these recorded distance points, the computational effort required to determine the control parameter curve also increases.

[0005] Against this background, a person skilled in the art faces the task of enabling a more efficient modeling of a road section in front of a vehicle. In particular, all relevant properties of the road section that are required to model a control parameter for controlling a vehicle, preferably an autonomous vehicle, are to be captured.

[0006] This object is achieved by a device for determining a discrete representation of a road section in front of a vehicle, comprising: an input interface for receiving sensor data from a sensor with information about the road section in front of the vehicle; a setting unit for determining a control distance at which a property of the road section in front of the vehicle relevant for controlling the vehicle changes, based on the sensor data, and for setting a reference point in a discrete representation of the road section that corresponds to the control distance, wherein the setting unit is designed to set a smaller predefined second number of reference points based on a predefined first number of reference points; and an output interface for outputting the smaller predefined second number of support points to an optimizer for determining a course of at least one control parameter for controlling a vehicle function based on the second number of support points.

[0007] The above object is further achieved by a system for determining a discrete representation of a road section in front of a vehicle, comprising: a sensor for generating sensor data with information about a section of road in front of the vehicle; a device as defined above; an optimizer for determining a course of at least one control parameter for controlling a vehicle function based on the support points in the discrete representation; and a vehicle control unit for controlling at least one vehicle function based on a control parameter curve determined by the optimizer.

[0008] The above object is further achieved by a method for determining a discrete representation of a road section in front of a vehicle, comprising the steps: Receiving sensor data from a sensor with information about the road section in front of the vehicle; Determining a control distance at which a property of the road section in front of the vehicle relevant for controlling the vehicle changes, based on the sensor data; Setting a vertex in a discrete representation of the roadway section corresponding to the control distance, wherein a vertex is set based on a predefined first number of vertexes and a smaller predefined second number of vertexes; and Outputting the smaller predefined second number of support points to an optimizer for determining a course of at least one control parameter for controlling a vehicle function based on the second number of support points.

[0009] Further aspects of the invention relate to a corresponding computer program product with program code for carrying out the steps of the method when the program code is executed on a computer, as well as a storage medium on which a computer program is stored which, when executed on a computer, effects execution of the method described herein.

[0010] Preferred embodiments of the invention are described in the dependent claims. It is understood that the features mentioned above and those to be explained below can be used not only in the respective combinations specified, but also in other combinations or alone, without departing from the scope of the present invention. In particular, the system, the method, and the computer program product can be implemented according to the embodiments described for the device and the system in the dependent claims.

[0011] The input interface for receiving sensor data allows the device to be easily integrated into an existing sensor system of a preferably autonomously driving vehicle. It is understood that sensor data can include both raw data from a sensor and already processed data from a sensor. In particular, the sensor data can already comprise a discrete representation with reference points at constant intervals. Using the setting unit, it is easy to ensure that all properties of the road section in front of the vehicle relevant for controlling the vehicle are recorded and processed in a reduced set of reference points.Because the setting unit is designed to set a smaller, predefined second number of support points based on a predefined first number of support points, a reduced set of support points can be created for an optimizer. In this way, it can be reliably ensured that the determination of a profile of at least one control parameter can be carried out with less computational effort. The smaller second number of support points can be output to an optimizer via the output interface. This makes it technically simple to use the device to create a discrete representation of a road section in front of the vehicle with a smaller number of support points and transmit this representation for further processing.

[0012] In a preferred embodiment, the setting unit is designed to set a reference point in the representation for a control distance at which the property relevant for controlling the vehicle comprises a discrete event.

[0013] Additionally or alternatively, the setting unit is designed to set a plurality of support points with a predefined maximum point spacing in the discrete representation for control intervals at which the property relevant for controlling the vehicle comprises a continuous event. Examples of a discrete event are changes in speed limits, traffic control signs such as traffic lights, other road users and / or a change in the permitted maximum speed, preferably indicated by traffic signs. By setting at least one support point in the discrete representation, it can be easily ensured in a technical manner that the relevant property for controlling the vehicle is captured in the discrete representation. Furthermore, by setting only one support point, the number of support points in the discrete representation can be kept low. Examples of a continuous event are inclines in the roadway and curves.By setting multiple control points with a predefined maximum point spacing, the continuous course of the continuous event can be modeled with sufficient accuracy. The predefined maximum point spacing can vary depending on the complexity of the continuous event. In particular, the predefined maximum point spacing should be chosen such that an optimizer can model the course of a control parameter with at least sufficient accuracy.

[0014] In an advantageous embodiment, the input interface is configured to receive map data from an on-board computer and / or an external system, wherein the map data includes information regarding curves, gradients, speed limits, environmental zones, tunnels, and / or stops on the road section. This allows the device to reach a result more efficiently and quickly, since only a comparison with the stored map material is necessary. Furthermore, it is conceivable to use a simpler and more cost-effective setting unit for the comparison.

[0015] In an advantageous embodiment, the setting unit is configured to set support points that are closer to the vehicle in the discrete representation with a smaller point spacing than more distant support points. This can, in particular, ensure that the discrete representation corresponds to a sufficiently wide section of roadway in front of the vehicle, allowing a profile of a control parameter for controlling the vehicle to be formed more precisely in the near future. This is especially true since more support points have been set to form the profile of a control parameter.

[0016] In an advantageous embodiment, the setting unit is configured to set a first reference point at the location of an origin of the discrete representation and to set another reference point at an end point of the discrete representation. The origin of the discrete representation corresponds to the current vehicle position. By setting a reference point at the origin, which corresponds to the current vehicle position, and at an end point, which corresponds to an end of the road section in front of the vehicle, it is technically easy to ensure that the control parameter is formed for the relevant area.

[0017] In an advantageous embodiment, the setting unit is designed to set a reference point at each control distance at which the property relevant for controlling the vehicle comprises a change in the speed limit. A reference point can also be set at a control distance at which the property comprises a static traffic element, preferably a traffic light, a traffic sign, an intersection and / or a preceding object. Furthermore, a reference point can be set at a control distance at which the property comprises a pedestrian crossing, a tunnel, an underpass and / or a stop. By setting additional reference points at the above-mentioned locations, it can be technically easily ensured that information relevant to control and road safety is taken into account when shaping or modeling a course of a control parameter for a preferably autonomously driving vehicle.Road safety is increased.

[0018] In a further advantageous embodiment, the setting unit is designed to determine a predefined maximum cornering speed. In addition, the setting unit is designed to determine from a set of support points of the discrete representation those support points whose maximum cornering speed, due to a curve curvature, is lower than the maximum permitted speed based on traffic regulations. Furthermore, the setting unit is designed to reject all support points from the set of support points except for one support point whose maximum cornering speed is minimal. The maximum cornering speed is preferably predefined by a limit based on the maximum lateral acceleration in curves. In particular, further information, such as the weather and / or the road surface, can also be taken into account here.The above-described design of the setting unit makes it technically easy to ensure that a safe cornering speed is maintained when modeling the course of at least one control parameter for controlling a preferably autonomously driving vehicle. Another advantage is that the number of required reference points is kept to a minimum.

[0019] In a further advantageous embodiment, the setting unit is configured to perform a further pass for setting support points and, based on the predefined second number of support points, to set additional support points and / or to discard support points. This makes it technically easy to ensure that a predetermined discrete number of support points is set in the discrete representation. This allows, in particular, the shaping of the at least one control parameter relevant for controlling the vehicle to take place quickly and reliably. Furthermore, the discrete representation can be improved during a second pass.

[0020] In a further advantageous embodiment, the setting unit is configured to determine both the gradient and the height at each support point from the first number of support points. The setting unit is configured to examine each support point from the first number of support points step by step in ascending order. Additionally, the setting unit is configured to store the gradient and height at a support point if this support point from the second number of support points has already been set in the discrete representation.Furthermore, the setting unit is designed to set a reference point from the second number of reference points in the discrete representation and to store a height and gradient at this reference point if a deviation between the last stored gradient at a reference point from the first number of reference points is greater than a predefined threshold or if a deviation between the last stored height and the current height at a reference point from the first number of reference points is greater than a further predefined threshold. This makes it technically easy to shape the at least one control parameter required for controlling an autonomously driving vehicle with regard to a continuous progression of properties. In particular, it can be ensured that there are no jumps in the discrete representation that are in particular greater than a predefined threshold.The formation of a control parameter curve can be done quickly and efficiently.

[0021] In a further advantageous embodiment, the setting unit is designed to set the support points at a predefined maximum point spacing, which is preferably defined depending on the distance of the support points from the vehicle. The setting unit is further designed to set a new support point midway between an existing first and second support point or, starting from a first support point, to set a new support point with the predefined maximum point spacing. This ensures that the individual support points are sufficiently close together to enable optimal shaping of the at least one control parameter based on the support points.

[0022] In a further advantageous embodiment, the setting unit is designed, once all of the second number of support points have been set, to compare a distance of the support point currently to be set from the vehicle with a distance of the support point furthest from the vehicle and to set the support point with the shorter distance from the vehicle of the two support points. This makes it technically simple and reliable to ensure that the predefined second number of support points is not exceeded. Furthermore, it is ensured that all of the information necessary for modeling at least one control parameter is present in the discrete representation. It is understood that this can shorten the road section represented by the discrete representation.

[0023] According to the invention, the setting unit is designed to set a further support point in the discrete representation before and / or after a control interval at which the property relevant for controlling the vehicle comprises a discrete event, if further support points can be assigned from the second number of support points. This makes it technically easy to ensure that the predefined second number of support points is adhered to. By setting them before or after a discrete event, the course of the at least one control parameter can be shaped more precisely. The additional support points preferably do not represent any additional information. For example, a reduction in a maximum speed can occur, preferably announced by a traffic sign.By providing at least one additional reference point in the discrete representation before the speed reduction, the optimizer can select a speed at this reference point and thus shape the reduction process more precisely. This can, in particular, increase safety and driving comfort, since no abrupt changes to a control parameter, such as the speed in this example, occur.

[0024] Possible control parameters for controlling a vehicle may include, in particular, a steering angle, a speed, and / or an acceleration. Furthermore, a battery charge level may be taken into account, particularly for a hybrid and / or a purely electric vehicle. Furthermore, a control parameter may also include a gear ratio of a vehicle's transmission.

[0025] A discrete representation is a digital model, or a digital image, of a real road section in front of a vehicle. A reference point in the discrete representation corresponds to a control distance on the real road section. Additional parameters, such as the gradient of the road at the reference point / control distance, a permitted and / or calculated speed, a traffic regulation, etc., can be stored for a reference point. In this way, an image of the road section can be created that preferably contains all relevant information about the road section.

[0026] An optimizer determines the course of a control parameter for a vehicle function based on the reference points and predefined or definable optimization criteria. Optimization criteria can include, in particular, energy consumption, occupant comfort, and safety. For example, a continuous course of a control parameter can be determined based on the discrete reference points by interpolating between the reference points.

[0027] A vehicle function is, in particular, an executable control of the vehicle, which is preferably carried out based on a control parameter. Vehicle functions can include, for example, a steering angle, acceleration, and / or braking. It is understood that a vehicle function can include a control loop for regulating a vehicle control system based on a control parameter, wherein the control parameter preferably includes variables such as a speed, a trajectory, and the like.

[0028] A continuous event describes a road property that changes monotonously, such as the curvature of a curve or the gradient of the road. A discrete event describes a road property that changes abruptly from one state to another, such as a speed limit or the change of a traffic light.

[0029] The invention is described and explained in more detail below using selected embodiments in conjunction with the accompanying drawings. They show: Fig. 1 a schematic representation of a situation in road traffic with a vehicle with a device according to the invention; Fig. 2 a schematic representation of a device according to the invention; Fig. 3 schematically shows a flow diagram of individual steps that can be carried out by means of a device according to the invention; Fig. 4 schematically shows a method for setting or discarding support points; Fig. 5 is a schematic representation of a method for setting a support point; Fig. 6 a schematic representation of a system according to the invention; and Fig. 7 a schematic representation of the individual steps of a method according to the invention.

[0030] Fig. 1 schematically shows a system 10 for determining a discrete representation of a road section in front of a vehicle 12. The system 10 detects a road section in front of the vehicle 12 by means of a sensor 14. The system 10 comprises a device 16 for determining a discrete representation of a road section in front of the vehicle 12 and the sensor 14. In the illustrated embodiment, the device 16 and the sensor 14 are integrated into the vehicle 12. It is understood that it is also conceivable for the device 16 and / or the sensor 14 to be implemented separately.

[0031] As in Fig. As shown in Figure 1, various objects 18, such as other road users, in particular vehicles, or even static objects such as trees, houses, traffic signs, traffic lights, or the like, can be detected. The sensor 14 can, in particular, be a radar or lidar sensor and / or a camera.

[0032] The approach of the invention is based on creating a discrete representation of a road section in front of the vehicle 12 based on the sensor data. For this purpose, automatic sign recognition and traffic sign recognition can be performed, for example. Furthermore, the course of the road can be determined. In particular, a parameter can be recorded in the sensor data that is specified on an absolute and / or relative scale. Furthermore, the parameter can be multidimensional.

[0033] A setting unit of device 16 can determine from the sensor data a control distance at which at least one property of the road section in front of vehicle 12 relevant for controlling vehicle 12 changes, and based on this, set a reference point in the discrete representation. It is understood that sensor 14 can be configured to preprocess the sensor data. In particular, it can be provided that the sensor already creates a digital representation in which, for example, reference points are provided at a uniformly discrete distance.

[0034] Using system 10, a discrete representation can be created that has a predefined, fixed number of reference points. This allows an optimizer to improve the shape of a control parameter for controlling at least one vehicle function. In particular, a substantially homogeneous shape, i.e., without abrupt changes, can be created. This can, on the one hand, improve ride comfort. On the other hand, it can lead to energy-efficient driving, since, in particular, unnecessarily fast and energy-inefficient acceleration processes can be avoided.

[0035] In Fig. 2 schematically illustrates a device 16 according to the invention. The device 16 receives sensor data 20 from a sensor 14 and comprises an input interface 22, a setting unit 24, and an output interface 26. The device 16 according to the invention can, for example, be integrated into a vehicle control unit or be designed as part of a driver assistance system or be implemented as a separate module. It is possible for the device 16 according to the invention to be partially or completely implemented in software and / or hardware. The various units and interfaces can be designed individually or in combination as a processor, processor module, or software for a processor.

[0036] Sensor data 20 from a sensor 14 is received via the input interface 22. In particular, data from a radar or lidar sensor and / or a camera can be received. For example, the input interface 22 can be connected to a vehicle bus system to receive the sensor data. Furthermore, it is conceivable that the input interface 22 can receive map data provided by an on-board computer and / or by means of an external system. The map data can, in particular, include information regarding curves, gradients, speed limits, environmental zones, tunnels, and / or bus stops.

[0037] In the setting unit 24, based on the sensor data 20, a control distance is determined at which at least one property of the road section in front of the vehicle 12 relevant for controlling the vehicle 12 changes. Such properties can be, for example, a gradient, a curve radius, a traffic rule, and / or objects 18 on the road section in front of the vehicle 12. The setting unit 24 can set a reference point in a discrete representation of the road section in front of the vehicle 12, wherein the reference point corresponds to the control distance. The setting unit 24 is further configured to set a smaller, predefined second number n2 of reference points based on a predefined first number n1 of reference points. This can be done in a first pass. It is understood that the setting unit 24 can also be configured to perform multiple passes to set the predefined second number n2 of reference points.The term “traversal” preferably means scanning and analyzing the individual support points step by step.

[0038] A discrete representation 30 is output to an optimizer via the output interface 26 when the setting unit 24 has set the predefined second number n2 of support points. The discrete representation 30 can be output to an optimizer via a vehicle bus system. A vehicle control unit is preferably also connected to the bus system. The optimizer is designed to determine a profile of at least one control parameter for controlling a vehicle function based on the second number n2 of support points. The optimizer can output the profile of the at least one control parameter in the form of a control command to a vehicle control unit of the vehicle 12 via the vehicle bus system, wherein the vehicle control unit then controls the vehicle functions according to the control command.

[0039] In Fig. 3 schematically shows individual steps of a flow chart which represents a possible setting of a predefined second number n2 of support points by means of the setting unit 24.

[0040] In step A, for example, a reference point is placed at the origin, i.e., at the current position of vehicle 12. Furthermore, another reference point is placed at the end of the road section under consideration, in front of vehicle 12.

[0041] In step B, the speed limit is taken into account, with the setting unit 24 setting a reference point at each point where the speed limit changes. A changing speed limit can be detected, for example, by automated sign recognition. Furthermore, it is conceivable that map material with a stored maximum permitted speed is stored, and the setting unit determines a speed limit by comparing the current vehicle position with the stored map material.

[0042] In step C, a control point is set for each static traffic element that must be visible for optimizing a control parameter. For example, a control point is set at the positions of traffic lights, intersections, pedestrian crossings, tunnels, underpasses, and / or stops.

[0043] In a step D, preceding objects 18, preferably motor vehicles, cyclists and / or other road users are taken into account and a reference point is set at each control distance at which a preceding object 18 is located.

[0044] In a step E, a maximum speed in curves in the road section ahead of the vehicle 12 is taken into account. A maximum speed in curves results, for example, from a limitation of the maximum permitted lateral acceleration. In this step, point ranges of the digital representation 30 are analyzed. The size of these point ranges is preferably dependent on a distance from the vehicle 12. In particular, nearby areas comprise a smaller section than more distant areas. Within an area, the reference points are determined at which the maximum speed due to the curvature of the curve is lower than a maximum permitted speed based on traffic regulations. If no such reference point is found, no reference point is set in the discrete representation 30. If a reference point with such properties is determined, it is set in the discrete representation 30.If multiple points have this property, the one with the smallest maximum allowed curve speed is selected. Preferably, all other points are discarded.

[0045] In a step F, the elevation profile of the roadway section (route section) in front of the vehicle 12 is considered. For each reference point in the digital representation 30, both the gradient and the elevation at this reference point are considered. The elevation can, for example, be determined relative to the current elevation of the vehicle 12. Preferably, each reference point is traversed in ascending order, i.e., with increasing distance from the vehicle 12, with the following logic being mapped. If a point has already been set in the discrete representation 30, the gradient and elevation at this point are saved.If no support point has been set and if a deviation between a last saved gradient and a gradient at a support point currently being examined is greater than a first threshold, or if a deviation between the last saved height and the height at the currently examined support point is greater than a second predefined threshold, then a support point is set in the discrete representation 30 and the gradient and height at this set support point are saved. In all other cases, no new support point is set in the discrete representation 30. In other words, this step ensures that a change in gradient or height in the considered road section in front of the vehicle 12 is taken into account and that sufficient support points are available in the digital representation 30.Furthermore, if there are not enough support points in the digital representation 30, at least one new support point is set in the digital representation 30.

[0046] In a step G, it is ensured that a maximum permitted interpolation point distance is not exceeded. Preferably, a maximum permitted interpolation point distance is defined as a function of the distance of the interpolation point to be set from the vehicle 12. For example, it can be provided that in an area up to 100 m in front of the vehicle 12, a new interpolation point must be present at least after 10 m. Furthermore, it can be provided, for example, that for distances of >100 m to the vehicle 12, a new interpolation point must be present at least after 50 m. If the requirement defined above is not yet met, a new interpolation point is inserted between already existing interpolation points in the discrete representation 30. This insertion can be carried out several times if necessary until the criterion defined above is met. This method results in point distances that lie between half the maximum point distance and the maximum point distance.

[0047] It is understood that a new support point cannot necessarily be inserted midway between two existing support points; rather, starting from a first support point, another support point can be set with the maximum point spacing. This results in a larger point spacing closer to the vehicle than at the end of the considered road section in front of the vehicle 12.

[0048] If, after completing step G, further support points can be assigned from the predefined second number n2 of support points, they are preferably inserted between two points with the largest point distance.

[0049] In a step H, the curve of at least one parameter relevant to controlling the vehicle is then calculated based on the previously set reference points. Such a parameter can be, for example, a speed, an acceleration, a steering angle, or the like. These values ​​are preferably stored together with the corresponding reference points so that an optimizer can interpolate between the values ​​to generate a control command for a vehicle control unit, which enables the vehicle control unit to implement the control parameter curve.

[0050] When running the routine described above, it may happen that all of the reduced, predefined second number n2 of interpolation points have already been assigned. In this case, for a interpolation point currently to be set, a check is carried out to determine whether the interpolation point to be set lies before or after an already set interpolation point that is furthest away from vehicle 12. If the interpolation point currently to be set lies before the furthest away interpolation point, the furthest away interpolation point is overwritten. If the interpolation point currently to be set lies after the furthest away interpolation point, the interpolation point currently to be set is discarded. This shortens the considered road section in front of vehicle 12, which is represented by the discrete representation 30.

[0051] If points can still be awarded from the predefined reduced second number n2 of points, steps B, C and D can be extended as follows. Not only can a reference point be set at a location of the event under consideration, but one or more reference points can be set before or after it. Preferably, the additional points do not represent any additional information. These additional reference points serve as reference points for the optimizer, which can better shape a control parameter curve using the additional reference points. An example of this would be a reduction in the maximum permitted speed, for example in the case of a traffic sign. By providing an additional reference point in the digital representation 30 before the reduction, the optimizer can select a speed at this point and thereby shape the curve of the speed reduction more precisely.

[0052] In Fig. 4 schematically shows a graph 32 showing the curve of a determined vehicle speed 34 and the curve of a permitted speed 36. A speed is plotted on the Y-axis 38, and a distance is plotted on the X-axis 40. The curve of the vehicle speed 34 and the permitted speed 36 is observed in a section 42, which is represented by a curly bracket. The curve of the vehicle speed 34 is modeled using a first reference point 44 and a second reference point 46. For example, the graph can represent a curve speed curve.

[0053] The first point 44 is determined based on the maximum permissible cornering speed and has a speed that is higher than the permitted speed 36. This can be seen in the diagram because point 44 lies above the permitted speed 36. Driving at the speed represented by point 44 is therefore not in compliance with traffic regulations. Therefore, in the subsection 42 under consideration, of the two reference points 44 and 46, reference point 44 is discarded. Reference point 46 also represents a determined cornering speed, whereby the determined cornering speed according to reference point 46 is below the permitted maximum speed 36. Consequently, reference point 46 is retained.

[0054] It is understood that points 44 and 46 are chosen only as examples. In particular, there may be multiple points available to model the speed curve 34. For clarity, however, this example is limited to two points. Point 46 thus represents the minimum vehicle speed 34 within the permitted speed range 36.

[0055] In Fig. 5 shows another diagram 48. As in Fig. 4, the speed is plotted on the Y-axis 38 and the distance on the X-axis 40. The setting of additional support points is explained in diagram 48. For this purpose, a maximum point distance 50 is represented by a curly bracket. The distance between a first support point 44 and a second support point 46 is greater than the permitted maximum point distance 50. Therefore, a further support point must be set between the two support points 44, 46. This can be done by setting a further support point 51a, which is set at the maximum point distance 50 from the first support point 44. It goes without saying that a further support point 51b can also be set midway between the two support points 44, 46.

[0056] In Fig. Figure 6 schematically shows a system 10 according to the invention in a motor vehicle 12. The system 10 according to the invention comprises a sensor 14, a device 16 according to the invention, an optimizer 52, and a vehicle control unit 54. The individual components of the system 10 are interconnected, whereby both a wireless and a wired connection, preferably via a bus system of the vehicle 12, can be provided.

[0057] As already described above, the device 16 receives sensor data from the sensor 14 and processes it to create a discrete representation 30 with a predefined second number n2 of support points. This discrete representation 30 is transmitted to the optimizer 52, which, based on the support points, forms the curve of a control parameter for at least one vehicle function of the vehicle 12 and generates a control command corresponding to the curve and transmits it to the vehicle control unit 54. The vehicle control unit 54 then controls at least one vehicle function according to the control command from the optimizer 52.

[0058] In Fig.Figure 7 schematically shows the individual steps of a method according to the invention for determining a discrete representation 30 of a road section in front of a vehicle 12. In a step S10, sensor data 20 from a sensor 14 containing information about the road section in front of the vehicle 12 is received. In a step S12, a control distance at which a property of the road section in front of the vehicle 12 relevant for controlling the vehicle changes is determined based on the sensor data. In a step S14, a reference point is set in a discrete representation 30 of the road section that corresponds to the control distance. The reference point is set based on a predefined first number n1 of reference points and a smaller predefined second number n2 of reference points.In a step S16, the smaller predefined second number n2 of support points is output to an optimizer 52, wherein the optimizer 52 determines a profile of at least one control parameter for controlling a vehicle function based on the second number n2 of support points.

[0059] The invention has been comprehensively described and explained with reference to the drawings and the description. The description and explanation are to be understood as exemplary and not restrictive. The invention is not limited to the disclosed embodiments. Other embodiments or variations will become apparent to those skilled in the art upon use of the present invention and upon careful analysis of the drawings, the disclosure, and the following claims.

[0060] In the claims, the words "comprising" and "having" do not exclude the presence of further elements or steps. The undefined article "a" or "an" does not exclude the presence of a plurality. A single element or unit may perform the functions of several of the units recited in the claims. An element, unit, interface, device, and system may be partially or completely implemented in hardware and / or software. The mere mention of some measures in several different dependent claims should not be understood to mean that a combination of these measures cannot also be advantageously used. A computer program may be stored / distributed on a non-volatile data carrier, for example, on an optical memory or on a solid-state drive (SSD).A computer program may be distributed together with hardware and / or as part of hardware, for example, via the Internet or via wired or wireless communication systems. Reference signs in the patent claims are not to be construed as limiting. Reference symbol 10 systems 12 vehicles 14 Sensor 16 Device 18 objects 20 sensor data 22 Input interface 24 setting unit 26 Output interface 30 discrete representation 32 Diagram 34 Vehicle speed 36 Course of the permitted speed 38 Y-axis 40 X-axis 42 subsection 44 first base 46 second base 48 further diagram 50 maximum point spacing 52 optimizers 54 Vehicle control unit AH Steps of a flowchart S10-S16 Method steps of a method according to the invention n1 first number n2 second number

Claims

[1] Device (16) for determining a discrete representation (30) of a road section in front of a vehicle (12), comprising: an input interface (22) for receiving sensor data (20) from a sensor (14) with information about the road section in front of the vehicle; a setting unit (24) for determining a control distance at which a property of the road section in front of the vehicle relevant for controlling the vehicle changes, based on the sensor data, and for setting a reference point in a discrete representation of the road section that corresponds to the control distance, wherein the setting unit is designed to set a smaller predefined second number (n2) of reference points based on a predefined first number (n1) of reference points; and an output interface (26) for outputting the smaller predefined second number (n2) of support points to an optimizer (52) for determining a course of at least one control parameter for controlling a vehicle function based on the second number (n2) of support points, characterized by , that the setting unit (24) is designed, when further support points from the second number (n2) of support points can be set, to set a further support point in the discrete representation (30) before and / or after a control distance at which the property relevant for controlling the vehicle (12) comprises a discrete event. [2] Device (16) according to claim 1, wherein the setting unit (24) is designed to to set a reference point in the discrete representation (30) for a control distance at which the property relevant for controlling the vehicle (12) comprises a discrete event and / or for control distances at which the property relevant for controlling the vehicle (12) comprises a continuous event, to set a plurality of support points with a predefined maximum point distance (50) in the discrete representation (30). [3] Device (16) according to one of claims 1 or 2, wherein the input interface (22) is designed to receive map data from an on-board computer and / or an external system, wherein the map data comprises information regarding curves, gradients, speed limits, environmental zones, tunnels and / or stops on the road section. [4] Device (16) according to one of claims 1 to 3, wherein the setting unit (24) is designed to set support points that are closer to the vehicle (12) in the discrete representation (30) with a smaller point spacing than support points that are further away. [5] Device (16) according to one of claims 1 to 4, wherein the setting unit (24) is designed to set a first support point at an origin of the discrete representation (30) and to set a further support point at an end of the discrete representation (30). [6] Device (16) according to one of claims 1 to 5, wherein the setting unit (24) is designed to set a support point at each control distance at which the property relevant for controlling the vehicle (12) includes a change in the speed limit; comprises a static traffic element, preferably a traffic light, a traffic sign and / or an intersection; comprises a preceding object (18); and / or a pedestrian crossing, a tunnel, an underpass and / or a stop. [7] Device (16) according to one of claims 1 to 6, wherein the setting unit (24) is designed to to determine a predefined maximum cornering speed; to determine from a set of support points of the discrete representation (30) the support points whose maximum curve speed due to a curve curvature is lower than the maximum permitted speed due to traffic regulations; and to discard all support points from the set of support points except for one support point whose maximum curve speed is minimal. [8] Device (16) according to one of claims 1 to 7, wherein the setting unit (24) is designed to carry out a further pass for setting support points and to set further support points and / or to discard support points based on the second number (n2) of support points. [9] Device (16) according to one of claims 1 to 8, wherein the setting unit (24) is designed to to determine for each support point from the first number (n1) of support points both the gradient and the height at that support point; to examine step by step each vertex from the first number (n1) of vertices in ascending order; if a support point from the second number (n2) of support points is already set in the discrete representation (30), to store the gradient and height at this support point; and if a deviation between the last saved gradient and the current gradient at a support point from the first number (n1) of support points is greater than a predefined threshold or a deviation between the last saved height and the current height at a support point from the first number (n1) of support points is greater than a further predefined threshold, to set a support point from the second number (n2) of support points in the discrete representation and to store a gradient and height at this support point. [10] Device (16) according to one of claims 1 to 9, wherein the setting unit (24) is designed to to set the support points at a predefined maximum point distance (50), which is preferably defined as a function of a distance of the support points from the vehicle (12); and to set a new support point between an already existing first support point and a second support point in the middle between the first and second support point or starting from the first support point with the predefined maximum point distance. [11] Device (16) according to one of claims 1 to 10, wherein the setting unit (24) is designed, when all the support points from the second number (n2) of support points have been set, to compare a distance of the support point currently to be set from the vehicle (12) with a distance of the support point furthest away from the vehicle and to set the support point with the smaller distance from the vehicle of the two support points. [12] System (10) for determining a discrete representation (30) of a road section in front of a vehicle (12), comprising: a sensor (14) for generating sensor data (20) with information about a road section in front of the vehicle; a device (16) according to one of claims 1 to 11; an optimizer (52) for determining a course of at least one control parameter for controlling a vehicle function based on the support points in the discrete representation; and a vehicle control unit (54) for controlling at least one vehicle function based on a control parameter profile determined by the optimizer. [13] Method for determining a discrete representation (30) of a road section in front of a vehicle (12), comprising the steps: Receiving (S10) sensor data (20) of a sensor (14) with information about the road section in front of the vehicle; Determining (S12) a control distance at which a property of the road section in front of the vehicle relevant for controlling the vehicle changes, based on the sensor data; Setting (S14) a support point in a discrete representation of the roadway section corresponding to the control distance, wherein a support point is set based on a predefined first number (n1) of support points and a smaller predefined second number (n2) of support points; and Outputting (S16) the smaller predefined second number (n2) of support points to an optimizer (52) for determining a profile of at least one control parameter for controlling a vehicle function based on the second number (n2) of support points. [14] A computer program product comprising program code for performing the steps of the method according to claim 13 when the program code is executed on a computer.

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