Method and device for determining object trajectories of objects in a vehicle environment of a vehicle and corresponding vehicle

Abstract

Method for determining object trajectories (z) of objects (DO, SO) in a vehicle environment of a vehicle (F), comprising the steps: Determine (S1) the respective distances (x0, x1, y0, y1) and relative velocities (v0, v1, w0, w1) of the objects (DO, SO) in relation to the vehicle (F); Classifying (S2) the objects (DO, SO) into static objects (SO) and dynamic objects (DO) based on the determined distances (x0, x1, y0, y1) and / or the determined relative velocities; and Calculating (S3) object trajectories (z) of the dynamic objects (DO) relative to the static objects (SO) based on the determined distances (x0, x1, y0, y1) of the objects (DO, SO) and / or based on the determined relative velocities (v0, v1, w0, w1) of the objects (DO, SO), whereby a change in position (D) of the vehicle (F) is determined based on the calculated object trajectories (z) of the dynamic objects (DO) and based on the determined relative velocities (v0, v1) of the dynamic objects (DO).

Description

[0001] The invention relates to a method and a device for determining object trajectories of objects in a vehicle environment of a vehicle, as well as a vehicle.

[0002] In many applications in the field of automotive engineering, such as parking assistants, lane keeping assistants, or autonomous driving, precise knowledge of the distances between the vehicle and other objects, the movements of other objects, or the movements of the vehicle itself is crucial. For example, German patent application DE 102 37 331 A1 discloses a method for measuring distances in which microwaves are emitted by a vehicle and reflected by other objects. By measuring the reflected microwaves, the distance to these objects can be determined.

[0003] If your own vehicle is in motion, accurately determining the movement of other objects in the vehicle's environment or the movement of your own vehicle is often difficult.

[0004] Furthermore, DE 10 2014 221 763 A1 discloses a method for the automatic control of one or more objects within a spatially defined area intended or designed for the manufacture, maintenance, or parking of a vehicle. The vehicle includes vehicle sensors with at least one sensor for detecting part of the environment of the spatially defined area and provides data representing the object(s) in the vehicle's environment.

[0005] It is therefore an object of the invention to precisely determine the movements of objects in the vehicle environment or the movements of the vehicle.

[0006] This problem is solved by a method for determining object trajectories of objects in the vicinity of a vehicle, comprising the features of claim 1, a device for determining object trajectories of objects in the vicinity of a vehicle, comprising the features of claim 9, and a vehicle comprising the features of claim 13. Further preferred embodiments are the subject of the dependent claims. According to a first aspect, the present invention thus provides a method for determining object trajectories of objects in the vicinity of a vehicle, wherein the respective distances and relative velocities of the objects with respect to the vehicle are determined. The objects are classified into static objects and dynamic objects based on the determined distances and / or the determined relative velocities.Object trajectories of the dynamic objects are calculated relative to the static objects based on the determined distances of the objects and / or the determined relative velocities of the objects.

[0007] The term "vehicle" refers in particular to motor vehicles, such as passenger cars, trucks, motorcycles, e-bikes, airplanes or ships.

[0008] Dynamic objects are those that are in motion, while static objects are stationary. Other road users, such as vehicles, bicycles, or pedestrians, can therefore be both static and moving objects. Examples of other static objects include lane boundaries, lane markings, trees, bushes, or obstacles.

[0009] The distances and / or relative velocities of the objects are preferably determined as two- or three-dimensional vector quantities, that is, they have an absolute value and a direction.

[0010] An object trajectory is understood to be a path of movement of the object, along which the object moves.

[0011] According to a further aspect, the invention relates to a device for determining the trajectories of objects in the vicinity of a vehicle. The device comprises a detection unit configured to determine the respective distances and relative velocities of the objects with respect to the vehicle. The device further comprises an evaluation unit configured to classify the objects into static and dynamic objects based on the determined distances and / or relative velocities. The evaluation unit is further configured to calculate the trajectories of the dynamic objects relative to the static objects based on the determined distances and / or relative velocities of the objects.

[0012] According to another aspect, the invention relates to a vehicle with a device for determining object trajectories of objects in a vehicle environment of the vehicle.

[0013] The invention makes it possible to distinguish between static and dynamic objects. By knowing the precise trajectories of dynamic objects, the driver can better assess the vehicle's surroundings. The calculated object trajectories can also be made available to other road users or devices outside the vehicle and evaluated by them.

[0014] According to the invention, a change in the vehicle's position is determined based on the calculated object trajectories of the dynamic objects and using the determined relative velocities of these objects. A change in position is understood as a change in the vehicle's motion over time relative to an initial position at a given time. The method is particularly advantageous in situations where a large number of dynamic objects are present in the vehicle's environment, such as in stop-and-go traffic or on busy roads. This provides a large number of possible reference points for determining the vehicle's change in position, thereby improving the accuracy of the position change calculation.

[0015] According to a further embodiment of the method, for each dynamic object, at least one change in the vehicle's position is calculated based on the calculated object trajectory of the dynamic object and using the determined relative velocity of the dynamic object. Furthermore, an average change in the vehicle's position is calculated by averaging or weighted averaging the calculated changes in position. The greater the number of dynamic objects, the more accurate the determination of the vehicle's change in position becomes.

[0016] According to a further embodiment of the method, at least one change in position is calculated for each static object. This change is determined based on the calculated distances between the static objects, and these changes are then weighted to calculate the average change in position. The precise change in position is thus determined both relative to the dynamic objects and relative to the static objects.

[0017] According to a preferred embodiment of the method, at least one vehicle driving parameter is determined, and at least one change in position is calculated based on this parameter. The averaged change in position is then calculated using a weighted average. A driving parameter can be, in particular, a wheel diameter, wheel slip, wheel angle, wheel rotation speed, steering angle, speed, or acceleration. Preferably, the change in position is determined from the vehicle driving parameters using a kinematic model. Thus, the method combines various methods for determining the change in position and can therefore improve the accuracy of the averaged change in position.

[0018] According to a preferred further development of the method, determining the relative velocities of the objects includes determining the magnitudes of the velocities and the directions of motion of the objects.

[0019] According to another embodiment of the method, the speed and direction of motion of the vehicle are determined. An object is classified as static if and only if its speed is substantially equal to the speed of the vehicle and its direction of motion is substantially opposite to the direction of motion of the vehicle. For example, the magnitude of the difference between the speed of the object and the speed of the vehicle must be less than a first predetermined threshold, and the magnitude of the vector sum of the direction of motion of the object and the direction of motion of the vehicle must be less than a second predetermined threshold.Conversely, if the magnitude of the difference between the speed of the object and the speed of the vehicle is greater than or equal to the first predetermined threshold, or if the magnitude of the vector addition of the direction of motion of the object and the direction of motion of the vehicle is greater than or equal to the second predetermined threshold, then the object is classified as a dynamic object.

[0020] According to a preferred embodiment of the method, information about at least one calculated object trajectory and / or change in the vehicle's position is wirelessly transmitted and / or received. In particular, the information can be wirelessly transmitted to or received from another road user via car-to-car communication. Even if the other road user does not have its own sensors that would allow it to determine its trajectory, it still receives information about its movement based on the transmitted object trajectory.

[0021] According to a preferred refinement of the method, for each of the dynamic objects, a separate object trajectory of the dynamic object relative to each static object is calculated. This generates a larger number of measured values. By weighted averaging these measured values, the actual object trajectory of the dynamic object can be determined even more accurately.

[0022] According to the invention, the evaluation device of the apparatus is further designed to determine a change in the position of the vehicle based on the calculated object trajectories of the dynamic objects and using the averaged relative velocities of the dynamic objects.

[0023] According to a preferred embodiment of the device, it has a sensor device which is configured to measure at least one driving parameter of the vehicle, wherein the evaluation device is further configured to additionally determine the changes in position of the vehicle on the basis of the at least one driving parameter of the vehicle measured by the sensor device.

[0024] According to a further preferred embodiment, the device has a wireless communication device which is configured to wirelessly transmit and / or receive information about at least one object trajectory and / or change in position of the vehicle calculated by the evaluation device.

[0025] According to a further preferred embodiment, the device includes a driver assistance system configured to control a driving function of the vehicle based on the calculated object trajectories. The driver assistance system can, for example, initiate an evasive maneuver or a braking maneuver. A vehicle function can, for example, include accelerating, decelerating, or steering the vehicle, as well as controlling actuators such as a turn signal or a windshield wiper.

[0026] The present invention will be explained in more detail below with reference to the exemplary embodiments shown in the schematic figures of the drawings.

[0027] They show: Fig. 1 a flowchart for determining object trajectories of objects in a vehicle environment of a vehicle according to an embodiment of the invention; Fig. 2 a schematic top view of a traffic scenario to illustrate the procedure in a vehicle-fixed coordinate system; Fig. 3 that in Fig. 2 illustrated exemplary traffic scenarios in a space-fixed coordinate system; Fig. 4 a schematic block diagram of a device for determining object trajectories of objects in a vehicle environment according to one embodiment; and Fig. 5 a schematic block diagram of a vehicle according to an embodiment of the invention.

[0028] Where appropriate, the described embodiments and further developments can be combined with one another as desired. Further possible embodiments, further developments, and implementations of the invention also include combinations of features of the invention described previously or subsequently with regard to the exemplary embodiments, even if not explicitly mentioned.

[0029] The accompanying drawings are intended to provide a further understanding of the embodiments of the invention. They illustrate embodiments and, in conjunction with the description, serve to explain the principles and concepts of the invention. Other embodiments and many of the aforementioned advantages become apparent with reference to the drawings. The elements of the drawings are not necessarily shown to scale. Identical reference numerals denote identical or similarly functioning components. The numbering of process steps is for clarity and is generally not intended to imply a specific chronological sequence.

[0030] Fig. Figure 1 shows a flowchart for determining object trajectories of objects in the vehicle environment of a vehicle according to an embodiment of the invention. The method is illustrated by the diagram in Figure 1. Fig. Two illustrated traffic scenarios are explained in more detail. Fig. Figure 2 shows a schematic top view of a vehicle F and objects SO and DO in the vicinity of vehicle F, which are moving relative to vehicle F. The traffic scenario is illustrated in a vehicle-fixed two-dimensional coordinate system in which vehicle F is located at a predetermined fixed point. The positions of objects SO and DO are illustrated at an initial time t0 of a detection segment and at an end time t1 of the detection segment.

[0031] In process step S1, the respective distances and relative velocities of objects SO and DO relative to the vehicle F are measured. The distances and relative velocities are preferably represented as two-dimensional vectors, with the vectors pointing from the vehicle F to the respective objects SO and DO. According to further embodiments, the distances and relative velocities can also be represented as three-dimensional vectors.

[0032] Preferably, both the distances x0 and y0 and relative velocities v0 and w0 of objects DO and SO at the initial time t0, as well as the distances x1 and y1 and relative velocities v1 and w1 at the final time t1, are determined. The distances and relative velocities can be determined continuously or at predetermined time intervals. The vehicle F has a sensor device for determining the distances and relative velocities, which may include a radar sensor, a lidar sensor, a laser sensor, or a stereo camera.

[0033] In a further process step S2, the objects SO, DO are classified into static objects SO and dynamic objects DO. For this purpose, the vehicle F's sensor system determines a vector velocity at the initial time t0. The velocities of the vehicle F and the objects SO, DO are each characterized by a velocity magnitude of the vehicle F or object SO, DO and a direction of motion normalized to a unit length. For each object SO, DO, it is checked whether the determined relative velocity of the object SO, DO, as a vector quantity, is essentially opposite to the vector velocity of the vehicle F.Preferably, it is checked whether the magnitude of the difference between the velocity of object SO, DO and the velocity of vehicle F is less than a first predefined threshold, and whether the magnitude of the vector addition of the direction of motion of vehicle F and the direction of motion of object SO, DO is less than a second predefined threshold, i.e., whether the direction of motion of vehicle F is substantially opposite to the direction of motion of object SO, DO. If this is the case, the object is recognized or classified as a static object SO. If either condition is not met, the object is recognized or classified as a dynamic object DO. Fig. In the two illustrated traffic scenarios, a dynamic object DO, for example another vehicle, and a static object SO, for example a tree, are detected.

[0034] The classification of objects into static objects SO and dynamic objects DO is preferably performed only at the start time t0. However, according to further embodiments, the classification can also be performed at the end time t1, where the end time t1 simultaneously represents the start time of a new detection segment. According to further embodiments, the detection process is only repeated after a predetermined number of detection segments. For example, the duration of a detection segment can be 0.1 seconds, and the detection process can be repeated after every 10 detection segments.

[0035] In an alternative embodiment, the objects can transmit signals about their state of motion via wireless communication, in particular whether they are static or dynamic. The vehicle F can have a communication device configured to receive the transmitted signals. The objects are classified as static or dynamic based on the received signals.

[0036] In a further process step S3, a Fig. 3. Illustrated object trajectory z of the dynamic object DO relative to the static object SO calculated. Fig. 3 shows the in Fig. Figure 2 illustrates a traffic scenario in a fixed coordinate system, where the static object SO is located at a fixed, predetermined point. First, a vector initial distance z0 and a vector final distance z1 of the dynamic object DO from the static object SO are determined, which point from the static object SO to the dynamic object DO at the initial time t0 and the final time t1, respectively. The initial distance z0 and the final distance z1 are calculated by vector subtracting the determined distance x0 and x1 of the dynamic object DO with respect to the vehicle F from the determined distance y0 and y1 of the static object from the vehicle F at the initial time t0 and the final time t1, respectively, using the following formulas: z0=x0−y0, z1=x1−y1.

[0037] The object trajectory z of the dynamic object DO is determined as the vector difference between the final distance z1 and the initial distance z0, that is, according to the following formula: z=z1−z0.

[0038] Preferably, the calculation of the object trajectory z is continued iteratively for any number of further acquisition sections. The entire object trajectory z of the dynamic object DO is calculated by concatenating the object trajectories determined in the respective acquisition sections, thus forming a polygonal path.

[0039] In a possible further embodiment, the object trajectory z is transmitted from the dynamic object DO or another object in the environment to the vehicle F via wireless communication.

[0040] Preferably, a change in position D of the vehicle F is further determined. For this purpose, a relative motion of the dynamic object DO relative to the vehicle F is subtracted from the object trajectory z of the dynamic object DO. The motion of the dynamic object DO relative to the vehicle F is determined using a time integral of the relative velocities over the interval [t0, t1] or using an approximation of this integral, e.g., using the trapezoidal formula. In the case of the trapezoidal formula, an average relative velocity is determined by averaging the relative velocities v0 and v1 of the dynamic object DO at the initial time t0 and at the final time t1, and the average relative velocity is multiplied by a duration t1-t0 of the detection period. The relative motion thus obtained is subtracted from the object trajectory z to obtain the change in position D of the vehicle F.The change in position D is therefore calculated according to the following formula: D=z−(t1−t0)⋅(v0+v1) / 2.

[0041] For a large number of acquisition sections, the position change D is determined individually for each acquisition section, and then an overall position change D is determined by chaining the individual position changes D.

[0042] For a large number of static objects SO, the position change D can preferably be determined separately for each dynamic object DO, and then an averaged position change D can be determined by weighted averaging over the calculated position changes D. The averaging is preferably performed separately for each acquisition section.

[0043] For a large number of dynamic objects DO, a position change D of the vehicle F can preferably be calculated for each dynamic object DO according to the method described above, and the average position change D of the vehicle F can be calculated by weighted averaging over the calculated position changes D. The averaging is preferably performed separately for each acquisition segment.

[0044] According to a further embodiment, the object trajectory z of the dynamic objects DO relative to the static objects SO is determined based on a known distance between two static objects. For example, if the distance between two lane markings representing static objects is known, the object trajectory z of the dynamic object DO relative to the static objects SO can be determined by evaluating a camera image.

[0045] Furthermore, the change in position D of the vehicle F for each static object SO can be calculated by taking the difference between the determined distance y0 of the static object SO from the vehicle F at the start time t0 and the determined distance y1 of the static object SO from the vehicle F at the end time t1, that is, according to the following formula: D=y0−y1.

[0046] Furthermore, the change in position D of vehicle F can be calculated by determining a driving parameter of vehicle F and calculating the change in position D of vehicle F based on at least one determined driving parameter of vehicle F. Thus, the change in position of any vehicle F can be measured using a kinematic model based on the vehicle's acceleration, steering angle of vehicle F, and wheel rotation speeds of vehicle F.

[0047] An averaged position change D of the vehicle F can be performed by weighted averaging over any selection of the position changes D described above, and the averaged position change D of the vehicle F can be output.

[0048] According to one embodiment, the calculated object trajectory z and / or the determined change in position D of the vehicle F are transmitted wirelessly.

[0049] Fig. Figure 4 shows a schematic block diagram of a device 1 for determining object trajectories z of objects DO, SO in the vicinity of a vehicle F. The device 1 includes a detection unit 2, which is configured to determine the respective distances and relative velocities of objects DO, SO with respect to the vehicle F. The detection unit 2 can include sensor devices for distance determination, in particular radar sensors, camera sensors, lidar sensors, or laser sensors.

[0050] The device 1 further comprises an evaluation unit 3, which is configured to classify the objects DO, SO into static objects SO and dynamic objects DO based on the determined distances and / or relative velocities. The evaluation unit 3 is configured to calculate object trajectories z of the dynamic objects DO relative to the static objects SO based on the determined distances and / or relative velocities of the objects DO, SO.

[0051] Furthermore, the evaluation device 3 is preferably designed to determine a change in position D of the vehicle F based on the calculated object trajectories z of the dynamic objects DO and using the determined relative velocities of the dynamic objects DO.

[0052] The evaluation unit 3 can be configured to perform each of the above-described process steps of the various embodiments.

[0053] The device 1 further comprises a sensor device 4, which is configured to measure at least one driving parameter of the vehicle F. The evaluation device 3 is further configured to additionally determine the change in position D of the vehicle F based on the at least one driving parameter of the vehicle F measured by the sensor device 4. The sensor device 4 may include a wheel sensor for determining a wheel rotation rate or a wheel angle. The sensor device 4 may be configured to measure an acceleration or speed of the vehicle F or to determine a steering angle of the vehicle F.

[0054] Furthermore, the device includes a wireless communication device 5, which is configured to wirelessly transmit and / or receive information about at least one object trajectory z of the dynamic objects and / or the position change D of the vehicle F, calculated by the evaluation unit 3. The wireless communication device 5 can, for example, transmit this information to another vehicle or a central evaluation unit. Furthermore, the communication device 5 can be configured to wirelessly receive object trajectories z and / or the position change D of the vehicle F that were calculated and wirelessly transmitted by a corresponding device of another vehicle.

[0055] The device 1 preferably has a driver assistance system 6 which is designed to control a driving function of the vehicle F on the basis of the calculated object trajectories z and / or on the basis of the determined change in position D of the vehicle F. Fig. Figure 5 shows a schematic block diagram of a vehicle F according to an embodiment of the invention. The vehicle F has a device 1 for determining object trajectories z of objects SO, DO in a vehicle environment of the vehicle F, which corresponds in particular to one of the embodiments described above.

Claims

[1] Method for determining object trajectories (z) of objects (DO, SO) in a vehicle environment of a vehicle (F), comprising the steps: Determine (S1) the respective distances (x0, x1, y0, y1) and relative velocities (v0, v1, w0, w1) of the objects (DO, SO) in relation to the vehicle (F); Classifying (S2) the objects (DO, SO) into static objects (SO) and dynamic objects (DO) based on the determined distances (x0, x1, y0, y1) and / or the determined relative velocities; and Calculating (S3) object trajectories (z) of the dynamic objects (DO) relative to the static objects (SO) based on the determined distances (x0, x1, y0, y1) of the objects (DO, SO) and / or based on the determined relative velocities (v0, v1, w0, w1) of the objects (DO, SO), whereby a change in position (D) of the vehicle (F) is determined based on the calculated object trajectories (z) of the dynamic objects (DO) and based on the determined relative velocities (v0, v1) of the dynamic objects (DO). [2] Method according to claim 1; wherein for each dynamic object (DO) at least one position change (D) of the vehicle (F) is calculated based on the calculated object trajectory (z) of the dynamic object (DO) and using the determined relative velocity of the dynamic object (DO); and where an average change in the vehicle's position (F) is calculated by weighted averaging over the calculated changes in position (D). [3] Method according to claim 2, wherein for each static object (SO) at least one position change (D) is calculated, which is determined on the basis of the determined distances (y0, y1) of the static objects (SO), and over which the averaged position change is additionally weighted. [4] Method according to claim 2 or 3, wherein at least one driving parameter of the vehicle (F) is determined, and wherein at least one change in position is determined based on the at least one determined driving parameter of the vehicle (F), over which additional weighted averaging is carried out to calculate the average change in position. [5] Method according to any of the preceding claims, wherein determining the relative velocities of the objects (DO, SO) includes determining the magnitudes of the velocities and directions of motion of the objects (DO, SO). [6] Method according to claim 5, wherein an absolute speed of the vehicle (F) and a direction of movement of the vehicle (F) is determined, and an object (DO, SO) is classified as a static object (SO) if the magnitude of the speed of the object (DO, SO) is substantially equal to the absolute speed of the vehicle (F) and the direction of movement of the object (SO) is substantially opposite to the direction of movement of the vehicle (F). [7] Method according to any of the preceding claims, wherein information about at least one calculated object trajectory (z) and / or the change in position (D) of the vehicle (F) is wirelessly transmitted and / or received. [8] Method according to any of the preceding claims, wherein for each of the dynamic objects (DO) with respect to each static object (SO) a separate object trajectory (z) of the dynamic object (DO) relative to that static object (SO) is calculated. [9] Device (1) for determining object trajectories (z) of objects (DO, SO) in a vehicle environment of a vehicle (F), comprising: an investigative device (2) which is designed to determine the respective distances (x0, x1, y0, y1) and relative velocities (v0, v1, w0, w1) of the objects (DO, SO) in relation to the vehicle (F); and an evaluation device (3) which is configured to classify the objects (DO, SO) into static objects (SO) and dynamic objects (DO) based on the determined distances (x0, x1, y0, y1) and / or the determined relative velocities (v0, v1, w0, w1), and to calculate object trajectories (z) of the dynamic objects (DO) relative to the static objects (SO) based on the determined distances (x0, x1, y0, y1) and / or based on the determined relative velocities (v0, v1, w0, w1) of the objects (DO, SO), wherein the evaluation device (3) is configured to determine a change in position (D) of the vehicle (F) based on the calculated object trajectories (z) of the dynamic objects (DO) and based on the determined relative velocities (v0, v1) of the dynamic objects (DO). [10] Device (1) according to claim 9, comprising a sensor device (4) which is configured to measure at least one driving parameter of the vehicle (F), wherein the evaluation device (3) is further configured to determine the change in position (D) of the vehicle (F) additionally on the basis of the at least one driving parameter of the vehicle (F) measured by the sensor device (4). [11] Device (1) according to claim 9 or 10, comprising a wireless communication device (5) which is configured to wirelessly transmit and / or receive information about at least one object trajectory (z) calculated by the evaluation device (3) and / or the change in position (D) of the vehicle (F). [12] Device (1) according to one of claims 9 to 11, comprising a driver assistance system (6) which is configured to control a driving function of the vehicle (F) on the basis of the calculated object trajectories (z). [13] Vehicle (F) with a device (1) for determining object trajectories (z) of objects (DO, SO) in a vehicle environment of the vehicle (F) according to any one of claims 9 to 12.

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