Position determination of a line-like object

Abstract

Proposed is a method (160) for determining a position of a line-like object (170) on the basis of echo information of a vehicle ultrasonic transducer arrangement (140) comprising at least one ultrasonic transducer (130), said method comprising: providing (S3) the echo information, which describes at least three echo signals, wherein transmission and receipt positions of the echo signals are two- or three-dimensionally distributed; and determining (S5, S6, S7) a position of a line-like object (170) on the basis of the echo information and of an echo-based position determination model of a line-like object (170).

Description

[0001] 2022PF01087 1 DETERMINING THE POSITION OF A LINEAR OBJECT The present invention relates to a method for determining the position of a linear object, such as a curb, a handrail, a barrier, and / or a lamppost, based on echo information from a vehicle ultrasonic transducer arrangement containing at least one ultrasonic transducer. Furthermore, the present invention relates to a computer program product, a control device, and a vehicle. Vehicle ultrasonic transducer arrangements are characterized, among other things, by the fact that the individual ultrasonic transducers can receive echo signals in response to transmission pulses from different ultrasonic transducers and make them available for evaluation. However, ultrasonic information describing multiple echo signals typically does not contain any information about a measured angle at which the respective echo signal was received by the respective receiving ultrasonic transducer.This makes it difficult to determine the position of an object in space. For example, JP 2969202 B2 discloses a method for recognizing the shape of a three-dimensional object. For this purpose, those distance signals which do not correspond to a background distance are selected from a set of distance signals from several distance sensors arranged in a plane. The selected distance signals are related to a center of gravity of the selected distance signals and thus fed to a neural network in order to recognize the shape as an outline of a three-dimensional object in a plane. KR 101408089 B1 discloses a method for determining the position of an object in space using an ultrasonic transducer arrangement. For this purpose, an ultrasonic transducer arrangement is proposed which provides a transmitter and at least three receivers. The position of the object is then determined by means of a travel time comparison.This patent apparently assumes that all echoes originate from the same reflection point. This only applies to a point-like object. For extended objects, this greatly simplified assumption generally leads to a significant error in position determination. Furthermore, it is not easy to distinguish between point-like and line-like objects, and consequently, information about the position of a line-like object in space is not explicitly available. DE 102020121064 A1 discloses a method for tracking an object in the environment of a vehicle, wherein a plurality of detection points are recorded as a point cloud, and wherein the point cloud is evaluated using a mathematical model that approximates an object as a polygonal shape.Against this background, one object of the present invention is to provide means for determining a position of a linear object based on echo information. A linear object is to be understood here in particular as a curb, a handrail, a barrier and / or a lamppost. A position of a linear object can, for example, contain or be specified by a position and an orientation or main axis direction of the linear object. A position of a linear object can, for example, contain or be specified by a plurality of positions along the linear object. Accordingly, a method for determining a position of a linear object based on echo information from a vehicle ultrasonic transducer arrangement, which vehicle ultrasonic transducer arrangement contains at least one ultrasonic transducer, is proposed.The proposed method includes: providing echo information describing at least three echo signals, wherein the transmission and reception positions of the echo signals are distributed two- or three-dimensionally. The proposed method also includes: determining a position of a linear object based on the echo information and an echo-based position determination model of a linear object. 2022PF01087 3 It is therefore proposed to use, provide, and apply a special position determination model or a position determination model specifically designed to determine a position of a linear object from echo information. Thus, a position of a linear object can be detected with high accuracy while requiring relatively little computational effort. The proposed method is preferably a computer-implemented method so that the position of the linear object can be determined frequently and quickly.A computer can preferably be understood as a control device for a vehicle. The echo information can, in particular, be in the form of a data set, preferably a digital data set, for easier interchangeability between different devices or methods. The echo information can, for example, contain a time series with multiple echo signals. The echo information can, for example, contain multiple time series, each with an echo signal. The echo information can, for example, contain at least one time series, each with an echo signal, and at least one time series, each with a plurality of echo signals. Preferably, a transmission position is known for each echo signal, which is a position of a transmitting ultrasonic transducer at the time of transmission of an ultrasonic signal, whereupon the echo signal is received.Preferably, a reception position is known for each echo signal, which is the position of a receiving ultrasonic transducer at the time the echo signal is received. A linear object can also be understood, for example, as an object whose ultrasonic reflection points have a main axis, wherein, for example, an extension along the main axis is at least 4 times, preferably at least 8 times, and preferably at least 12 times an extension perpendicular to the main axis. A linear object can also be understood, for example, as an object whose ultrasonic reflection points are distributed approximately along a straight line in space, wherein this straight line can be regarded as a first main axis of a reflection point cloud.A linear object can also be understood, for example, as a reflection point cloud in which vertical distances between reflection points and the first main axis of the reflection point cloud are less than 10 cm, preferably less than 6 cm, and particularly preferably less than 2 cm. One can also speak, for example, of a characteristic distribution of reflection points influenced by the object geometry of a linear object. The proposed method can optionally include: providing position information that describes the relative positions of the transmitting and receiving positions to one another, in particular—if multiple ultrasonic transducers are present—the relative positions of the ultrasonic transducers of the vehicle ultrasonic transducer arrangement to one another. The proposed method can optionally include: determining the position of the linear object, also based on the position information.In other words, the proposed method can optionally include: determining the position of the linear object based on the echo information, the position information, and an echo-based attitude determination model for linear objects. By precisely knowing the relative positions of the transmit and receive positions, it is possible to precisely determine the position of the linear object. This proposed method can be reliably implemented, for example, for a stationary vehicle with three ultrasonic transducers in an at least two-dimensional arrangement. This proposed method can be reliably implemented, for example, for a moving vehicle with two ultrasonic transducers. This proposed method can be reliably implemented, for example, for a stationary vehicle with an at least two-dimensionally moving ultrasonic transducer, such as an ultrasonic transducer in a moving windshield wiper. The list is not exhaustive.This is therefore a method with broad benefits. 2022PF01087 5 The position information, such as a relative position of several ultrasonic transducers of the vehicle or of the vehicle ultrasonic transducer arrangement, can be included, for example, as a parameter in the attitude determination model. The position information, such as information indicative of movement of the vehicle between the transmission and reception positions, can be recorded and provided together with the echo information, for example. Mixed forms are also conceivable, such as a combination of known installation positions and additional movement of the vehicle. Information indicative of movement of the vehicle between the transmission and reception positions can, for example, be a vector by which the vehicle has moved between two transmission and reception positions.Preferably, the method is used for parking operations or the like at correspondingly low speeds, so that the movement of the vehicle between transmitting an ultrasonic wave and receiving its reflection can be negligible. For easier availability, the position information can, in particular, be in the form of a data set, preferably a digital data set.For example, the proposed method may take the form of: a method for determining a position of a linear object based on echo information from a vehicle ultrasonic transducer arrangement, which vehicle ultrasonic transducer arrangement contains at least two ultrasonic transducers, wherein the proposed method includes: providing the echo information describing at least three echo signals, wherein transmission and reception positions of the echo signals are distributed two- or three-dimensionally; and determining a position of a linear object based on the echo information and an echo-based position determination model of a linear object. Thus, a preferred embodiment includes two or more ultrasonic transducers in the ultrasonic transducer arrangement.In this method, the provided echo information preferably describes echo signals received during a journey of a vehicle having the vehicle ultrasonic transducer arrangement. Furthermore, the provided position information preferably contains a relative position of the at least two ultrasonic transducers of the vehicle ultrasonic transducer arrangement to one another, and it is preferably indicative of a relative movement of the journey.According to a preferred embodiment, the proposed method takes the form of: a method for determining a position of a linear object based on echo information from a vehicle ultrasonic transducer arrangement that contains at least three ultrasonic transducers, comprising: providing the echo information that describes at least three echo signals, wherein the transmission and reception positions of the echo signals are distributed two-dimensionally or three-dimensionally; and determining a position of a linear object based on the echo information and an echo-based position determination model of a linear object. The method may include: providing position information that describes relative positions of the ultrasonic transducers to one another; wherein the position of the linear object is also determined based on the position information. This embodiment is also applicable, for example, to a stationary vehicle orcan be carried out reliably with stationary ultrasonic transducers. The proposed method can optionally include: providing at least one initial position for the linear object. The proposed method can optionally include: repeatedly carrying out an approximation step, wherein in each case an end position for the linear object is determined based on a starting position for the linear object and the echo information using the position determination model, wherein the initial position is used first as the starting position and the end position of the previous execution is used for each subsequent execution. It has been found that repeated execution or application of the position determination model results in a significantly more accurate determination of the position of the linear object. Preferably, three to eight, in particular four to six, initial positions are provided.Preferably, one initial position is provided after the other, and then the approximation step is repeatedly executed. This can be terminated after a position of the linear object has been determined with sufficient accuracy according to a termination criterion without attempting to repeat the remaining initial positions. 2022PF01087 7 The attitude determination model is preferably equation-based or formula-based. The attitude determination model preferably contains an equation or a set of equations that describes at least one linear object based on an echo signal. Thus, one or more equations or formulas can be provided as calculation rules to deterministically and / or comprehensibly determine the position of the linear object. The term "transmitter-receiver combination" is used below.This designates a selected combination of a transmitting ultrasonic transducer and a receiving ultrasonic transducer, which can be the same ultrasonic transducer or different ultrasonic transducers. The transmitter-receiver combination can be referred to as a permutation. In other words, a transmitter-receiver combination can define one of the ultrasonic transducers as the transmitting ultrasonic transducer and one of the ultrasonic transducers as the receiving ultrasonic transducer. In other words, the transmitter-receiver combination means, for example, a selection of one ultrasonic transducer of the vehicle ultrasonic transducer arrangement as a transmitting ultrasonic transducer and another or different ultrasonic transducer or the same ultrasonic transducer of the vehicle ultrasonic transducer arrangement as a receiving ultrasonic transducer for subsequent observation or examination.In the proposed method, a reflection position or reflection point may be assigned to several, and preferably all, transmitter-receiver combinations. In particular, a reflection position is assigned to all transmitter-receiver combinations considered in the further course of the method. The reflection position can be understood in particular as a position of an ultrasonic reflection of an ultrasonic signal from the transmitting ultrasonic transducer on the linear object to the receiving ultrasonic transducer of the transmitter-receiver combination. The reflection position is in particular a position in three-dimensional space which is located on and / or at the linear object. The reflection position can mean the point 2022PF01087 8 to which the strongest echo signal of the transmitter-receiver combination corresponds.The reflection position can mean the location to which the strongest echo signal corresponds in a time series of the transmitter-receiver combination. The reflection position can mean the location to which the strongest echo signal corresponds in a time window and / or in a signal strength window of a time series of the transmitter-receiver combination. In the proposed method, the echo information can identify or designate the transmitting ultrasonic transducer and the receiving ultrasonic transducer for each echo signal. For example, the transmitter-receiver combination can be explicitly specified in a data set of the echo information. For example, the transmitter-receiver combination can result from frequency information and / or time information, which can be derived from the echo information for the respective echo signal.In the proposed method, a set of all reflection positions may have a center of gravity and / or a first principal component. The center of gravity is, for example, a position in space that corresponds to an arithmetic mean of all reflection position coordinates. The first principal component is, for example, a vector in space for which the sum of the squared perpendicular distances of all reflection positions to this vector is minimal. In the proposed method, it may optionally be that the attitude determination model contains several equations, formulas, or terms, each of which compares two signal path lengths for a transmitter-receiver combination or specifies a signal path length difference between them.The first of the two signal path lengths is a path length from the transmitting ultrasonic transducer of this transmitter-receiver combination to the reflection position of this transmitter-receiver combination and further to the receiving ultrasonic transducer of this transmitter-receiver combination. The second of the two signal path lengths is a path length based on a travel time of the echo signal of this transmitter-receiver combination. The second signal path length can be determined in particular using an ambient temperature provided to the method. The equations of this option therefore limit the position of the respective reflection position using the signal travel time between the ultrasonic transducers of the respective transmitter-receiver combination. In the proposed method, it can optionally be the case that the attitude determination model contains several equations or formulas orContains terms which, for each transmitter-receiver combination, specify a deviation of a) a vector between the center of gravity and the reflection position of the transmitter-receiver combination from b) the first principal component. The equations of this option are therefore suitable for restricting the positions of the respective reflection positions so that they coincide with the first principal component or are as close as possible to and / or adjacent to a straight line. These equations can be referred to as a collinearity requirement. With the proposed method, it is optional for the attitude determination model to contain several equations, formulas, or terms, each of which specifies an angular difference between two angles.The first of these two angles is an angle between, on the one hand, a vector from the transmitting ultrasonic transducer of the respective transmitter-receiver combination to the reflection position of the respective transmitter-receiver combination and, on the other hand, the first principal component of the set of reflection positions. The second of these two angles is an angle between, on the one hand, a vector from the reflection position of this transmitter-receiver combination to the receiving ultrasonic transducer of this transmitter-receiver combination and, on the other hand, the first principal component of the set of reflection positions. These equations therefore restrict the positions of the respective reflection positions so that they satisfy the reflection law with respect to the respective transmitter-receiver combination.In other words, it may be required that the angle of incidence of an ultrasonic pulse from the transmitting ultrasonic transducer to the linear object be equal to the angle of reflection of an ultrasonic echo from the linear object to the receiving ultrasonic transducer. 2022PF01087 10 The proposed method can optionally provide for the attitude determination model to be a trained attitude determination model. A trained attitude determination model is preferably trained using a plurality of training data sets to determine the position of a linear object. For example, each training data set contains echo information describing multiple echo signals, as well as a training position.An objective function of the training can be to minimize a difference between the training position of a training data set and a position determined by means of the position determination model on the basis of the echo information of the same training data set. According to one aspect of the invention, a computer program product is proposed, comprising instructions which, when the program is executed by a computer, cause the computer to carry out the described method for determining a position of a linear object on the basis of echo information from a vehicle ultrasonic transducer arrangement. A computer program product, such as a computer program means, can be provided or delivered, for example, as a storage medium, such as a memory card, USB stick, CD-ROM, DVD, or in the form of a downloadable file from a server in a network.This can be done, for example, in a wireless communications network by transmitting a corresponding file with the computer program product or the computer program means. According to one aspect of the invention, a control device for a vehicle is proposed, which is configured to carry out the described method for determining a position of a linear object based on echo information from a vehicle ultrasonic transducer arrangement. The embodiments and features described for the proposed method apply accordingly to the proposed control device. According to one aspect of the invention, a vehicle with a proposed control device is proposed. The vehicle preferably carries or contains the vehicle ultrasonic transducer arrangement. The vehicle ultrasonic transducer arrangement and the control device are preferably interconnected for data exchange.2022PF01087 11 Further possible implementations of the invention also include combinations of features or embodiments described previously or below with regard to the exemplary embodiments, which are not explicitly mentioned. In this case, the person skilled in the art will also add individual aspects as improvements or additions to the respective basic form of the invention. Further advantageous embodiments and aspects of the invention are the subject of the dependent claims and the exemplary embodiments of the invention described below. The invention is explained in more detail below using preferred embodiments with reference to the attached figures. Fig. 1 shows a schematic plan view of a vehicle having a control device configured to carry out a method for determining a position of a linear object, specifically according to one embodiment of the invention; Fig.2-4 schematically show a convergence of several exemplary reflection positions to an exemplary linear object in three steps of a method for determining a position of a linear object according to the embodiment of the invention; and Fig. 5 schematically shows a flow chart for the method for determining a position of a linear object according to the embodiment of the invention. In the figures, identical or functionally equivalent elements have been provided with the same reference numerals unless otherwise stated. 2022PF01087 12 Fig. 1 shows a schematic view of a vehicle 100 from a bird's eye view. The vehicle 100 is, for example, a car that is arranged in an environment 150. The car 100 has a control device 110, which can, for example, be part of a parking assistance system.In addition, several environmental sensor devices 120, 130 are arranged on the car 100, which are, for example, optical sensors 120 and ultrasonic transducers 130 or ultrasonic sensors. The optical sensors 120 include, for example, visual cameras, a radar and / or a lidar. The optical sensors 120 can each capture an image of a respective area from the environment 150 of the car 100 and output it as an optical sensor signal. The ultrasonic transducers 130 are configured to detect a distance to objects arranged in the environment 150 and to output a corresponding sensor signal. Using the sensor signals captured by the sensors 120, 130, the control device 110 is able to drive the vehicle 100 semi-autonomously or fully autonomously. In addition to the functions shown in Fig.In addition to the optical sensors 120 and ultrasonic transducers 130 shown in Figure 1, the vehicle 100 can be provided with various additional sensor devices 120, 130. Examples of these are a microphone, an acceleration sensor, an antenna with a coupled receiver for receiving electromagnetically transmittable data signals, and the like. Some of the ultrasonic transducers 130 of the vehicle 100 are combined, for example, to form a vehicle ultrasonic transducer arrangement 140. The ultrasonic transducers 130 of the vehicle ultrasonic transducer arrangement 140 are preferably not all distributed along a single straight line, but are preferably arranged in a two-dimensional plane or, more preferably, spatially distributed in / on the vehicle 100. The vehicle ultrasonic transducer arrangement 140 preferably only has ultrasonic transducers 130 whose detection ranges overlap. The following will be explained with reference to Figure2 to 5 describe an embodiment of a method 160 suitable for determining a position of a linear object 170 on the basis of (i.e., as a function of) echo information from the vehicle ultrasonic transducer arrangement 140, which includes at least one ultrasonic transducer 130. The described method 160 includes optional steps. In a step S1, a check is made as to whether a speed of the vehicle 100 does not exceed a speed threshold. The threshold can be, for example, up to 50 km / h and preferably up to 35 km / h. If the vehicle 100 is traveling too fast, the method 160 is preferably not executed any further. In a next step S2, echo information describing at least part of the surroundings 150 is acquired by means of the ultrasonic transducers 130 of the vehicle ultrasonic transducer arrangement 140. This echo information is provided in a step S3.The echo information takes the form of a digital data set, for example. The echo information describes multiple echo signals. An echo signal can be understood as an ultrasonic echo indicating a reflection. For example, the echo information contains a time series of an ultrasonic level for each of the ultrasonic transducers 130, with individual echo signals being derived from or read out from the time series. For example, the echo information contains multiple echo signals, each identified by time information, such as a timestamp or a propagation time. Each echo signal is uniquely assigned to a transmitting ultrasonic transducer 130 and a receiving ultrasonic transducer 130. The transmitting ultrasonic transducer 130 and the receiving ultrasonic transducer 130 form a transmitter-receiver combination. These can be different ultrasonic transducers 130 or the same ultrasonic transducer 130.In a next step S4, position information is provided. For example, the position information is read from a memory after starting the vehicle 100 or the control device 110 and / or at periodic intervals. The position information can be provided as a data set, in particular as a digital data set. In a next step S5, a position of the linear object 170 is determined based on the echo information and an echo-based position determination model of a linear object 170. A derivation of the exemplary position determination model is described below. The derivation is intended to facilitate understanding. "k" ultrasonic transducers 130 are considered for the position determination model. Preferably, all ultrasonic transducers 130 of the vehicle ultrasonic transducer arrangement 140 are considered.Thus, there are k relative positions Si of the ultrasonic transducers 130 to each other or within a vehicle-specific coordinate system, with each relative position S. i preferably defined by three Cartesian coordinates xi, yi, zi: S ^ ^ = ^x^ y^ z^^ ; i = 1 … k S^ = ^S^ ^ ⋯ All transmitter-receiver combinations of the ultrasonic transducers 130 under consideration are considered. Including the identity, k² transmitter-receiver combinations are thus possible. For each transmitter-receiver combination, a reflection position pi,j or a reflection point is considered, where "i" denotes the transmitter 130 and "j" the receiver 130: p ^ ^,^ = ^x^^,^ y^^,^ z^^,^^ ; i = 1 … k , j = 1 … kp ^ = ^p^,^ ^ p^,^ ^ ⋯ p^,^ ^ p^,^ ^ p^,^ ^ ⋯ p^,^ ^ ⋯ p^,^ ^^^×^^^ 2022PF01087 15 The totality or the set p T the reflection positions p i,jcan be understood as a point cloud or reflection point cloud. From the echo information, a path length w is determined for each echo signal. i,j based on a transit time TOF of the echo signal of this transmitter-receiver combination and preferably an ambient air temperature ϑ can be determined: The set or totality of reflection points p i,j has a center of gravity p): ^ ^ Using the center of gravity p) of the reflection points pi,j, reflection points p centered on the center of gravity can be determined. i,j * and determine a correspondingly centered reflection point cloud p*: p^,^ ∗ = p^,^ − p) ; i = 1 … k , j = 1 … k^ In the following, a principal component analysis is performed using singular value decomposition. The matrix p* is factorized: 2022PF01087 16 From the matrix V one can determine a direction vector d PC1Determine or extract the 1st principal component of the reflection points pi,j and then form it into a normalized direction vector dPC1n: ^ Thus, a principal line pPC1 of the reflection points pi,j can be determined or formed by the corresponding center of gravity p): p:;^ = p) + s ∗ d:;^>This line in parametric form with its position vector p), the direction vector d :;^> and the parameter s represents a potentially detected linear object. In this embodiment, a set of a total of 5k 2System equations are formulated. For example, the attitude determination model contains several equations, each of which specifies, for a transmitter-receiver combination, a difference between a) a path length from the transmitting ultrasonic transducer 130 to the reflection position p of this transmitter-receiver combination and further to the receiving ultrasonic transducer 130 and b) a path length based on a travel time of the echo signal of this transmitter-receiver combination: f^^p ^ = Gp^,^ − S^G + GS^ − p^,^G − w^,^ ⋮ 2022PF01087 17 ⋮ ⋮f^^^p ^ = Gp^,^ − S^G + GS^ − p^,^G − w^,^For example, the attitude determination model contains several equations, each of which determines for a transmitter-receiver combination a deviation a) of a vector between the center of gravity p) and the reflection position p i,j the transmitter-receiver combination to b) the 1st principal component d PC1 specify: f f f f f f f For example, the terms f ^ ^ H^ ^ p ^ , f ^ ^ H^ ^ p ^ and f ^ ^ H^ ^ p ^ a group of terms that together represent a deviation of the vector between the center of gravity p) and the reflection position p 1,1 on the one hand and the 1st principal component d PC1on the other hand. In other words, this group of terms specifies the vector product or cross product 2022PF01087 18 of the vector between the center of gravity p) and the reflection position p1,1 with the first principal component dPC1. For example, the attitude determination model contains several equations, each of which specifies an angular difference between a) an angle between a1) the vector from the transmitting ultrasonic transducer to the reflection position and a2) the first principal component, and b) an angle between b1) a vector from the reflection position to the receiving ultrasonic transducer and b2) the first principal component: ^ ^ f What the above equations have in common is that under ideal conditions they become zero if the calculated reflection positions p correspond to the actual reflection positions p on / at the linear object 170. Under real conditions, they will approximate zero. These equations together therefore form a zero-position problem. Step S5 has substeps S6 and S7. In step S6, at least one initial position for the linear object 170 is provided. In step S7, an end position for the linear object is determined using the position determination model based on a starting position for the linear object 170, the echo information, and the position information. Step S7 is an approximation step and is executed repeatedly. When the approximation step is executed for the first time, the initial position 2022PF01087 19 provided in S6 is used as the starting position.For each subsequent execution of step S7, the end position of the previous execution of step S7 is used. For example, step S7 may include a damped Gauss-Newton method for numerically solving the above equations: J^p>^^J^p>^Δp> = −J^p>^^f^p>^p>H^ = p> + λ>Δp>. A person skilled in the art chooses the value λ> according to a damping strategy such that λS^> <λ> < 1 is satisfied. The Jacobian matrix J(p) is generated, for example, according to the equations described above:. In other words, in step S7, the approximation method is used to calculate for each position value x ^^,^ , y ^^,^ and z ^^,^ each of the reflection positions pi,j a solution is approximated for which the terms f1(p) to f M^ ^ ^p ^ should be as close as possible to zero. In other words, the zeros of the system of equations are approximated, which contains the equations f1(p) to f M^ ^^ p^ After each execution of an approximation step of the Gauss-Newton method, the fulfillment of a termination condition is checked. If a termination condition is fulfilled, the approximation step is not executed again. A termination condition can be fulfilled, for example, if the reflection points p Taccording to the last end position, are no further than a predetermined threshold value from a common main axis. A termination condition 2022PF01087 20 can be met, for example, if the end position has not changed by at least a degree of accuracy between the last two executions. A termination condition can be met, for example, if a computing time threshold is exceeded during step S5. A termination condition can be met, for example, if a maximum number of executions of the approximation step is reached. Many numerical approximation methods can be used in step S7, and these can require further termination conditions that can be applied by a person skilled in the art. Figs. 2 to 4 show an exemplary scenario in which a position of the linear object 170 is determined.All three figures show the positions of four ultrasonic transducers 130 of a vehicle ultrasonic transducer arrangement 140. All four ultrasonic transducers 130 serve alternately as transmitting ultrasonic transducers 130 and as receiving ultrasonic transducers 130, so that the indicated linear object 170, for example, reflects 16 ultrasonic echoes, which thus correspond to 16 reflection points p. Furthermore, the position of the linear object 170 is shown for better clarity. Fig. 2 shows a position of the reflection points after the first execution of step S7, Fig. 3 shows the position after the second execution of step S7, and Fig. 4 shows the position after the third and final execution of step S7. The reflection points p i,j are shown as diamonds. It should be noted that in Figs. 2 to 4, several reflection points overlap in the drawing projection.After the third execution of step S7, the position of the linear object 170 is known with high precision, and therefore step S5 is aborted or ended. Finally, the final position of the linear object 170 determined in the last executed step S7 is output as the position of the linear object 170 in a step S8. For example, the position of the linear object 170 can be output, provided, and / or stored as a digital data set. The position of the linear object 170 to be output can, for example, be the determined reflection points p. T be or contain. The position to be output of the line-like object 2022PF01087 21 170 can, for example, be the 1st principal component p PC1 based on the determined reflection points p Tbe or contain. By deliberately varying the parameter s in the corresponding straight line equation p:;^ = p) + s ∗ d:;^>, additional points lying on the straight line can be calculated if necessary in addition to the already calculated reflection points. Although the present invention has been described using exemplary embodiments, it is susceptible to numerous modifications.

[0002] 2022PF01087 22 LIST OF REFERENCE SYMBOLS 100 Vehicle 110 Control device 120 Optical sensor 130 Ultrasonic transducer 140 Vehicle ultrasonic transducer arrangement 150 Environment 160 Method for determining a position of a linear object on the basis of echo information from a vehicle ultrasonic transducer arrangement that contains at least one ultrasonic transducer 170 Linear object S1 Checking whether a speed of the vehicle does not exceed a speed threshold S2 Detecting echo information that describes at least part of the environment by means of the ultrasonic transducers of the vehicle ultrasonic transducer arrangement S3 Providing the echo information,which contains several echo signals S4 Providing position information S5 Determining a position of a line-like object based on the echo information and an echo-based position determination model of a line-like object S6 Providing at least one initial position for the line-like object S7 Repeatedly executing an approximation step, wherein in each case based on a starting position for the line-like object and the echo information by means of the position determination model, an end position for the line-like object is determined, wherein the initial position is used first as the starting position and the end position of the previous execution is used for each further execution S8 Outputting the position of the line-like object,

Claims

2022PF01087 23 PATENT CLAIMS 1. Method (160) for determining a position of a line-like object (170) based on echo information of a vehicle ultrasonic transducer arrangement (140) containing at least one ultrasonic transducer (130), comprising: providing (S3) the echo information which describes at least three echo signals, wherein transmission and reception positions of the echo signals are distributed two- or three-dimensionally; and determining (S5, S6, S7) a position of a line-like object (170) based on the echo information and an echo-based position determination model of a line-like object (170).

2. Method according to claim 1, characterized in that the method includes: providing (S4) position information which describes relative positions (S i) of the transmitting and receiving positions relative to one another; wherein the position of the linear object (170) is also determined on the basis of the position information.

3. The method according to claim 1 or 2, characterized in that the vehicle ultrasonic transducer arrangement (140) contains at least two ultrasonic transducers (130), wherein the provided (S3) echo information describes echo signals received by the vehicle ultrasonic transducer arrangement (140) during a journey of a vehicle (100); and wherein the provided (S4) position information preferably contains a relative position of the at least two ultrasonic transducers (130) of the vehicle ultrasonic transducer arrangement (140) relative to one another and is indicative of a relative movement of the journey.

4. Method according to one of claims 2 to 3, characterized in that the vehicle ultrasonic transducer arrangement (140) contains at least three ultrasonic transducers (130); 2022PF01087 24 wherein preferably the provided (S4) position information relative positions (S i) of the ultrasonic transducers (130) of the vehicle ultrasonic transducer arrangement (140) to one another.

5. The method according to one of the preceding claims, characterized in that determining (S5) the position includes: providing (S6) at least one initial position for the linear object (170); and repeatedly executing (S7) an approximation step, wherein an end position for the linear object (170) is determined in each case on the basis of a starting position for the linear object (170) and the echo information by means of the position determination model, wherein the initial position is used first as the starting position and the end position of the previous execution is used for each further execution.

6. The method according to one of the preceding claims, characterized in that the position determination model is equation-based. 7.Method according to claim 6, characterized in that a transmitter-receiver combination (130, 130) contains a transmitting ultrasonic transducer (130) and a receiving ultrasonic transducer (130), which can be the same ultrasonic transducer (130) or different ultrasonic transducers (130); several and preferably all transmitter-receiver combinations (130, 130) are each assigned a reflection position (pi,j); the echo information for each echo signal identifies the transmitting ultrasonic transducer (130) and the receiving ultrasonic transducer (130); and the attitude determination model comprises several equations (f1(p) to f. ^ ^^p ^), which contains, for each transmitter-receiver combination (130, 130), a difference between a) a path length from the transmitting ultrasonic transducer (130) to the reflection position (p i,j) of this transmitter-receiver combination (130, 130) and further to the receiving ultrasonic transducer (130) and b) a path length based on a transit time of the echo signal of this transmitter-receiver combination (130, 130). 2022PF01087 25 8. The method according to claim 6 or 7, characterized in that: a transmitter-receiver combination (130, 130) contains a transmitting ultrasonic transducer (130) and a receiving ultrasonic transducer (130), which can be the same ultrasonic transducer (130) or different ultrasonic transducers (130); several and preferably all transmitter-receiver combinations (130, 130) are each assigned a reflection position (p i,j ) is assigned; a set of all reflection positions (pi,j) has a center of gravity (p)) and a first principal component (pPC1); and the attitude determination model has several equations (f ^ ^ H^ ^p ^ to f L^ ^^p ^) or groups of equations, which each contain for a transmitter-receiver combination (130, 130) a deviation a) of a vector between the center of gravity (p)) and the reflection position (pi,j) of the transmitter-receiver combination (130, 130) to b) the 1st principal component (p PC1 ) specify.

9. The method according to one of claims 6 to 8, characterized in that a transmitter-receiver combination (130, 130) contains a transmitting ultrasonic transducer (130) and a receiving ultrasonic transducer (130), which can be the same ultrasonic transducer (130) or different ultrasonic transducers (130); several and preferably all transmitter-receiver combinations (130, 130) are each assigned a reflection position (p i,j ) is assigned; a set of all reflection positions (pi,j) has a 1st principal component (pPC1); and the attitude determination model has several equations (f L^ ^ H^ ^p ^ to f M^ ^^p ^) or groups of equations, each of which contains for a transmitter-receiver combination (130, 130) an angular difference between a) an angle between a1) a vector from the transmitting ultrasonic transducer (130) to the reflection position (p i,j ) and a2) the 1st main component (p PC1 ) and b) an angle between b1) a vector from the reflection position (pi,j) to the receiving ultrasonic transducer (130) and b2) the 1st principal component (pPC1). 2022PF01087 26 10. A computer program product comprising instructions which, when executed by a computer, cause the computer to execute the method (160) for determining a position of a linear object (170) based on echo information from a vehicle ultrasonic transducer arrangement (140) according to one of claims 1-9.

11. A control device (110) for a vehicle (100), which is configured to execute the method (160) for determining a position of a linear object (170) based on echo information from a vehicle ultrasonic transducer arrangement (140) according to one of claims 1-9 and / or the computer program product according to claim 10.

12. A vehicle (100) having a control device (110) according to claim 11.

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