DE102019127859A1 - Determining the position of an object using ultrasound - Google Patents

Abstract

The present invention relates to a method for determining the position of an object (22) relative to a vehicle (10) by means of ultrasonic radiation, comprising the method steps: a) emitting ultrasonic radiation onto an object (22) located in a detection area of an ultrasonic sensor (16) at a point in time t1, when the vehicle (10) is at a first position relative to the object (22); b) detecting ultrasonic radiation emitted in method step a) and reflected by the object (22); c) emitting ultrasonic radiation onto the object ( 22) at a point in time t2, where t2 is after t1, and where the vehicle (10) is at a second position relative to the object (22) that is different from the first position; d) detection of and of emitted in method step c) the object (22) reflected ultrasound radiation; e) recording a time profile of the amplitude of the in method step b) and in method step d) detected ultrasonic radiation; andf) determining the angle and / or the position of the object (22) relative to the vehicle (10) based on a comparison of the angle-dependent amplitude curve of the ultrasonic radiation detected in method step b) and in method step d).

Description

The present invention relates to the determination of the position of an object by means of ultrasound. The present invention relates in particular to a method by which the position of an object relative to a vehicle can be determined by means of ultrasound, and to the use of this method in the context of a parking assistance method or maneuvering assistance method. The present invention also relates to a driving assistance system by means of which such a method can be carried out.

The use of ultrasonic sensors for driving support systems of vehicles is well known. Such sensors are arranged, for example, on the bumpers of the vehicle and are designed to detect the surroundings of the vehicle. The data recorded by the ultrasonic sensors can be made available to a driving support system, for example.

A problem with ultrasonic sensors can be that, due to the so-called time-of-flight measuring principle of such sensors, only the radial distance from objects can be determined in a conventional manner. For many applications, however, a more precise position determination, in particular with regard to the x-y position, would be helpful. According to methods from the prior art, this can be determined, for example, by trilaterating several sensors.

DE 195 41 459 A1 describes a method for determining the direction and distance of a measuring object with an ultrasonic transducer, in which for reference measurement the ultrasonic transducer (USW) is excited with a transmission signal (SS), a reference signal (SROn) reflected by a reference object (RO) at the ultrasonic transducer (USW) is received and stored with the associated location, these steps are repeated for different locations of the reference object (RO), in which the ultrasonic transducer (USW) is excited with the transmission signal (SS), in which the measurement signal (SMO ) is received and stored at the ultrasonic transducer (USW), in which an evaluation of the shape of the measurement signal (SMO) and the shape of the reference signals (SROn) is used to determine the direction and distance.

DE 40 01 493 A1 describes a method for the automatic or supporting control of movable devices with location sensors and environmental sensors for emitting sensor signals which are characteristic of the distance between the device and at least one obstacle, and with a processing unit into which the sensor signals are input and which at least one control signal for drives / braking / steering the device for accelerating / braking / steering the respective movement of the device in order to avoid a collision with the obstacle. Such a method should be characterized in that the processing unit is designed as a neural network, that the device automatically executes a predetermined movement cycle, that the sensor data obtained in the process are repeatedly entered into the neural network in a learning phase and the movement cycle is repeated in each case, and that if the value falls below of a given global error, the learning phase is completed and a transition is made to an optional phase in which the device autonomously executes a learned movement cycle that at least approximates the given movement cycle or corrects partially autonomous faulty and critical driving behavior.

US 2012/0293356 A1 describes that in a method for recognizing objects, at least one sensor emits a transmission pulse as a wave, in particular as an acoustic or electromagnetic wave, the wave being at least partially reflected by objects in the propagation space and the reflected wave being detected by at least one receiver as a received signal. The received signal of the reflected wave is divided into segments, and data is collected from the individual segments, which is used to determine an object hypothesis.

U.S. 5,548,512 A describes an autonomous navigation system for a mobile vehicle which is arranged to move in an environment, which comprises a plurality of sensors which are arranged on the vehicle, and at least one neural network which has an input layer coupled to the sensors, a a hidden layer coupled to the input layer and an output layer connected to the hidden layer. The neural network generates output signals which represent the respective positions of the vehicle, for example the X coordinate, the Y coordinate and the angular orientation of the vehicle. A variety of patch locations in the area are used to train the neural networks to generate the correct outputs depending on the distances detected.

Such solutions known from the prior art can offer further potential for improvement, in particular with regard to a simple and effective determination of the position of objects in a vehicle environment by means of ultrasonic sensors.

It is the object of the present invention to at least partially overcome the disadvantages known from the prior art. In particular, it is the object of the present invention to provide a solution by means of which a simple and effective position determination of objects in a vehicle environment is possible by means of ultrasonic sensors.

The object is achieved according to the invention by a method with the features of claim 1. The object is also achieved according to the invention by a use with the features of claim 9 and by a driving assistance system with the features of claim 10. Preferred embodiments of the invention are in the Subclaims described in the description or the figures, with further features described or shown in the subclaims or in the description or the figures individually or in any combination being able to represent an object of the invention if the context does not clearly indicate the contrary.

1. a) Emittieren von Ultraschallstrahlung auf ein in einem Erfassungsbereich eines Ultraschallsensors befindliches Objekt zu einem Zeitpunkt t1, wenn sich das Fahrzeug an einer ersten Position relativ zu dem Objekt befindet;
2. b) Detektieren von in Verfahrensschritt a) emittierter und von dem Objekt reflektierter Strahlung;
3. c) Emittieren von Ultraschallstrahlung auf das Objekt zu einem Zeitpunkt t2, wobei t2 nach t1 liegt, und wobei sich das Fahrzeug an einer zu der ersten Position verschiedenen zweiten Position relativ zu dem Objekt befindet;
4. d) Detektieren von in Verfahrensschritt c) emittierter und von dem Objekt reflektierter Strahlung;
5. e) Erfassen eines zeitlichen Verlaufs der Amplitude der in Verfahrensschritt b) und in Verfahrensschritt d) detektierten Strahlung; und
6. f) Bestimmen des Winkels und/oder der Position des Objekts relativ zu dem Fahrzeug basierend auf einem Vergleich des zeitlichen Verlaufs der Amplitude der in Verfahrensschritt b) und in Verfahrensschritt d) detektierten Strahlung.

A method is proposed for determining the position of an object relative to a vehicle by means of ultrasonic radiation, comprising the method steps:

1. a) emitting ultrasonic radiation onto an object located in a detection range of an ultrasonic sensor at a point in time t1 when the vehicle is located at a first position relative to the object;
2. b) detecting radiation emitted in method step a) and reflected by the object;
3. c) emitting ultrasonic radiation onto the object at a point in time t2, wherein t2 is after t1, and wherein the vehicle is at a second position relative to the object that is different from the first position;
4. d) detecting radiation emitted in method step c) and reflected by the object;
5. e) recording a time profile of the amplitude of the radiation detected in method step b) and in method step d); and
6. f) Determining the angle and / or the position of the object relative to the vehicle based on a comparison of the time profile of the amplitude of the radiation detected in method step b) and in method step d).

Such a method allows the position of an object in the vehicle environment to be reliably determined in a simple and effective manner.

The method described here is therefore used to determine the position of an object relative to a vehicle by means of ultrasonic radiation. In other words, the relative position of an object is to be determined on the basis of a vehicle, which is basically freely selectable but can, for example, be a motor vehicle. In principle, the object is also not restricted and can, for example, be a static or also a dynamic object. However, the object is particularly preferably a static object.

In order to carry out the method, the vehicle initially comprises an ultrasonic sensor, that is to say precisely one ultrasonic sensor or a plurality of ultrasonic sensors.

An ultrasonic sensor is used in a driving support system of a vehicle. As such, the ultrasonic sensor can be arranged, for example, in a bumper of the vehicle and, for example, with a plurality of further ultrasonic sensors of identical or different configuration, can be used, for example, to allow improved parking or to fundamentally reduce the risk of an accident. In principle, the ultrasonic sensors can thus be used to monitor the surroundings of the vehicle.

In a suitable design, the ultrasonic sensor can, for example, have a housing with a housing base body. A transmitting and receiving membrane for transmitting and receiving ultrasonic waves is arranged on a front side of the housing or the housing base body. This is intended to mean in particular that the transmitting and receiving membrane can be part of the housing, such as in particular the housing base body, or can at least partially be positioned on the housing or the housing base body, for example in such a way that the transmitting and receiving membrane with an active surface at least partially exposed. In this case, the membrane can have a pot area with a bottom area, wherein the bottom area can be excited to vibrate, for example by a piezo element, or can absorb reflected vibrations. The bottom area of the membrane is aligned on the front side or the bottom area defines the front side of the housing or the housing base body and thus the ultrasonic sensor.

Thus, the ultrasonic sensor can be used to send out or to emit ultrasonic waves as well as to receive or to detect ultrasonic waves.

Ultrasonic sensors emit ultrasonic waves over a certain angular range, both in a horizontal plane and in a vertical plane. Correspondingly, the echo radiation is also detected in this angular range. It is true that the detection of the ultrasonic waves does not enable an angle-determined or angle-dependent detection of the amplitude of the echo radiation. However, ultrasonic sensors usually have an angle-dependent amplitude of the emitted radiation and, accordingly, also of the detected radiation. This angle dependency of the amplitude is used to infer the angle from the two amplitude curves recorded at different times and thus at different locations.

If an amplitude is also spoken of, this can in principle relate to a property of the detected ultrasonic radiation. In particular, the amplitude relates to the detection strength, that is to say, for example, the received power or the received sound level of the ultrasonic radiation.

In the description and the claims, a temporal course of the amplitude or a temporal amplitude course is understood to mean the time-resolved amplitude received by the ultrasonic sensor after the ultrasonic radiation has been emitted.

To determine the position of the object relative to the ultrasonic sensor and thus relative to the vehicle, the method described here includes the following steps.

According to method step a), the method initially comprises emitting ultrasonic radiation onto an object located in a detection area of an ultrasonic sensor at a point in time t1 when the vehicle is at a first position relative to the object, in particular by an ultrasonic sensor positioned on the vehicle.

As described above, this method step can be carried out by an ultrasonic sensor. The ultrasonic radiation is emitted into a detection area or the detection area is determined by the emitted radiation. It is provided in particular that the ultrasonic radiation is emitted in a horizontal plane and / or in a vertical plane over a defined angular range. If there is also an object in the detection area, then the ultrasonic radiation is also emitted onto the object.

Furthermore, the ultrasonic radiation is emitted at a point in time t1 and also when the ultrasonic sensor or the vehicle is in a specific position relative to the object and thus at a first position relative to the object.

According to method step b), the method further comprises the detection of radiation emitted in method step a) and reflected by the object, that is to say from the so-called echo radiation. As already indicated above, this step can also be carried out by the ultrasonic sensor.

The further process steps c) and d) of the process described here essentially correspond to process steps a) and b) as described above. However, method step c) takes place at a point in time t2, which is after the point in time t1 of method step a) and also when the vehicle is in a different position compared to method step a). In other words, it is provided that the ultrasonic sensor is located in a moving vehicle which moves relative to the object and thereby carries out two successive measurements that take place at different locations.

According to method step e), the acquisition of a time profile of the amplitude of the radiation detected in method step b) and in method step d) is also provided.

According to method step f), the angle and / or the position of the object relative to the vehicle is determined based on a comparison of the time profiles of the amplitude of the radiation detected in method step b) and in method step d). The change in amplitude is analyzed, the cause of which is the different position of the vehicle or the sensor in relation to the object and thus the different angle of the vehicle or the ultrasonic sensor in relation to the object. With knowledge of the angle dependency of the ultrasonic sensors, conclusions can be drawn about the respective angle of the object to the sensor from this change in the amplitude curves over time. The angle and distance are therefore known, which enables the position of the object to be determined.

As described above, the method described here is based on the effect that it is provided in summary that the ultrasonic sensor is located in a moving vehicle which moves relative to the object and thereby carries out two successive measurements. In other words, successive echoes of the ultrasonic radiation are detected or recorded. This makes it possible for the vehicle to be at a mutually different angle relative to the object in the different measurements or in the successive measurements according to steps a) and b) or c) and d).

Because the time course of the amplitude is recorded at different relative positions of the vehicle to the object and thus at different angles of the ultrasonic sensor to the object, it is possible to compare the obtained time profiles of the amplitudes on the angle and / or the position of the object relative to be closed to the vehicle. In other words, the change in the temporal progression of the amplitude is analyzed, the cause of which is the different position of the vehicle or the sensor to the object and thus the different angle of the vehicle or the ultrasonic sensor to the object, which makes it possible to determine the position of the object.

The method can thus have the further method step, according to which the amplitude profiles obtained in each case on the basis of the radiation detected in method step b) and d) are compared and a change in the amplitude profiles is detected.

The advantage of this method can thus be seen, for example, in the fact that an effective and reliable determination of the position of objects relative to a vehicle is possible by means of ultrasonic sensors. A plurality of ultrasonic sensors is not required, as is the case with trilateration, for example. The necessary peripherals can thus be kept particularly small, which can save costs and effort during implementation.

In addition, the reliability of the measurement can be improved. This is because if, for example, when using a plurality of ultrasonic sensors for a trilateration, one ultrasonic sensor outputs an incorrect measurement result, the overall measurement or the position determination is also incorrect. If, on the other hand, a position determination is carried out with only one ultrasonic sensor or for each or more of the existing ultrasonic sensors separately, an erroneous result can be immediately noticed by a comparison with the other results of the other sensors and be given less attention.

Accordingly, it can be advantageous that method steps a) to f) are carried out for a single ultrasonic sensor. When using several ultrasonic sensors, it can be particularly preferred that method steps a) to f) are carried out separately for a plurality of ultrasonic sensors for each of the ultrasonic sensors. The corresponding positions of the objects obtained, which are obtained based on different sensors, can be compared with one another.

It can furthermore be possible not only to determine the position in an x-y plane, but also to determine a height position. This can be made possible, for example, in that, as indicated above, the amplitude is angularly dependent not only in a vertical plane but also in a horizontal plane.

With regard to the evaluation of the measurement results, it can be particularly preferred to carry this out on the basis of artificial intelligence. Accordingly, it can be preferred that method step f) takes place using a neural network and thus artificial intelligence. In particular, the neural network can be designed as a CNN (convolutional neural network) and in particular as a neural network with monitored learning (DNN with supervised learning).

In the field of machine learning, convolutional neuronal networks are a class of deep “feed-forward” artificial neural networks that have already been used in the analysis of visual images. CNNs use multilayer perceptrons designed to require minimal preprocessing. Convolutional neuronal networks were inspired by biological processes, whereby their interconnection pattern between neurons is based on the organization of the animal visual cortex. Individual cortical neurons respond to stimuli only in a limited region of the visual field known as the receptive field. The receptive fields of different neurons partially overlap so that they cover the entire visual field.

Compared to other algorithms, CNNs use relatively little preprocessing. This means that the network learns the filters that were created by hand in traditional algorithms. This independence from existing knowledge and human work performance in the creation of features is a great advantage in terms of the feasibility of the method.

By using a neural network, a measurement can be particularly adaptive or the results obtained from the time-shifted measurements can be are included particularly reliably in a position determination.

When using a neural network, it can be preferred that this is trained before the actual real measurement, so that the data obtained can be evaluated particularly preferably and used in determining the position of the object.

• g) Trainieren des neuronalen Netzes unter Verwendung der Verfahrensschritte:
  • g1) Emittieren von Ultraschallstrahlung auf ein in einem Erfassungsbereich eines Ultraschallsensors befindliches Objekt zu einem Zeitpunkt t3, wenn sich das Fahrzeug an einer dritten Position relativ zu dem Objekt befindet;
  • g2) Detektieren von in Verfahrensschritt g1) emittierter und von dem Objekt reflektierter Strahlung;
  • g3) Emittieren von Ultraschallwellen auf das Objekt zu einem Zeitpunkt t4, wobei t4 nach t3 liegt, und wobei sich das Fahrzeug an einer zu der drittem Position verschiedenen vierten Position relativ zu dem Objekt befindet;
  • g4) Detektieren von in Verfahrensschritt g3) emittierter und von dem Objekt reflektierter Strahlung;
  • g5) Aufzeichnen der relativen Position des Fahrzeugs zu dem Objekt bei den Verfahrensschritten g1) und g3); und
  • g6) Aufzeichnen jeweils eines zeitlichen Verlaufs der Amplitude basierend auf der in Verfahrensschritt g2) und g4) detektierten Strahlung oder Aufzeichnen einer Veränderung der zeitlichen Verläufe der Amplitude basierend auf der in Verfahrensschritt g2) und g4) detektierten Strahlung.

Thus, with regard to the use of a neural network, it can be preferred that the method has the further method step before method step a):

• g) Training the neural network using the process steps:
  • g1) emitting ultrasonic radiation onto an object located in a detection range of an ultrasonic sensor at a point in time t3 when the vehicle is located at a third position relative to the object;
  • g2) detecting radiation emitted in method step g1) and reflected by the object;
  • g3) emitting ultrasonic waves onto the object at a point in time t4, wherein t4 is after t3, and wherein the vehicle is at a fourth position relative to the object that is different from the third position;
  • g4) detecting radiation emitted in method step g3) and reflected from the object;
  • g5) recording the relative position of the vehicle to the object in method steps g1) and g3); and
  • g6) recording a temporal course of the amplitude based on the radiation detected in method step g2) and g4) or recording a change in the temporal course of the amplitude based on the radiation detected in method step g2) and g4).

The training thus runs essentially in accordance with the above-described real measurement, with method steps g5) and g6) differing in particular. In these method steps, a corresponding time profile of the amplitude is assigned to the corresponding relative positions of the vehicle to the object by determining the amplitude profile for the corresponding position and storing it for the relative position or by changing the time profile of the amplitude based on the radiation detected in method step g2) and g4) is stored or recorded.

Because the amplitude curves over time are used, the neural network can both evaluate the change in amplitude and also take into account the change in the distance between the object and the ultrasonic sensor. On the one hand, this can be used directly to infer the position of the object from the change in distance when the position change of the vehicle is known. On the other hand, this can be used to take into account the influence of the change in distance on the amplitude when determining the angle.

Furthermore, it can be particularly important that steps g1) to g4) are carried out at least twice in succession in order to change at least one of the temporal amplitude curve, the frequency and the spectral content in successive measurements and in different relative positions of the vehicle to the object so that in particular a change in at least one of the amplitude curve over time, the frequency and the spectral content can be advantageous for different measurements. The training of the neural network can thus have the further method step, according to which the temporal amplitude curves, frequencies and / or spectral contents obtained based on the radiation detected in method steps g2) and g4) are compared and a change in the temporal amplitude curves, the frequency and / or of the spectral content is recorded and, if necessary, recorded. In the context of the invention, recording can be understood to mean, for example, storage in a memory.

Then, in a real measurement according to method steps a) to f), the determined temporal amplitude curve, the frequency and / or the spectral content can be assigned to a relative position of the vehicle to the object, in particular taking into account the change in the different temporal amplitude curves, frequencies and / or spectral contents which in turn indicates the position of the vehicle relative to the object or, in other words, can enable the object to be determined relative to the vehicle.

It can thus be provided that method step g) or method steps g1) to g4) are used to train a neural network and that, after training of the neural network, the position of the object relative to the vehicle is determined by method steps a) to d).

After training the neural network, it may be possible for the neural network to have amplitude curves over time immediately or their change is assigned to a relative position, thus determining the position of objects after training the neural network.

However, it cannot be ruled out that after the training of the neural network it is trained again or further and / or that, depending on the circumstances and, for example, in the case of non-trained states, further training sequences may be run through.

It can furthermore be preferred that the vehicle is guided along a guide and moved along the object during method step g). Thus, in this embodiment, training can be carried out at least in part or at least part of the training of the neural network in such a way that the vehicle is guided on a guide during method step g) and thus moves along the object at a defined distance and along a defined trajectory becomes. The object can understandably be a different object than is used in a real measurement according to method steps a) to f). In this refinement, it can be achieved that an exact relative position of the object to the vehicle is known at all times. This means that the training can take place very precisely, which in turn can further improve the real measurements or make the measurement results more reliable. Thus, a driving assistance method based on these data or results can also be particularly reliable.

Furthermore, it can be preferred that method steps a) to d) are carried out according to a predetermined time frequency. This refinement only requires very little computing power, since the corresponding measurements can be carried out independently of the external circumstances and only as a function of time, and the position of objects can thus be determined. The time frequency can be preset and selected based on empirical values, for example. In principle, the time frequency can be freely selected.

As an alternative or in addition, it can be provided that method steps a) to d) are carried out adaptively over time based on at least one driving characteristic of the vehicle. Examples of corresponding driving properties of the vehicle include, for example and not by way of limitation, the speed of the vehicle and the trajectory, such as the distance that exists between the vehicle and the object. This refinement allows a highly adaptive position determination, it being possible to carry out a corresponding position determination in particular in driving sequences in which the exact position of the object relative to the vehicle is important.

For example, at low speeds and / or short distances from the object, it can be assumed that a driving sequence, such as a parking process or a maneuvering process, is carried out in which the vehicle is driven or has to be driven comparatively close to objects. Therefore, in order to avoid accidents, it is very important to determine the exact position of the objects. In contrast, at high speeds, objects are mostly passed at a greater distance, so that a highly accurate knowledge of the position of the objects may not be of great importance.

With regard to further features or advantages of the method, reference is made to the description of the use, the driving assistance system and the vehicle, and vice versa.

A use of a method, as described in detail above, for a parking assistance method or a maneuvering assistance method is also described.

As indicated above, the method described here can be advantageous in particular at low speeds and / or short distances from the object, since it can be assumed here that a driving sequence, such as a parking process or a maneuvering process, is carried out in which the vehicle is relatively close Is driven along objects or has to be driven. Therefore, in order to avoid accidents, it is very important to determine the exact position of the objects.

During a parking process, for example, the method can be used to measure a parking space. In order to precisely determine the length of the space, it is necessary to know the shape of the bumper or a similar object delimiting the parking space.

Following the above, the use described here allows a particularly effective application of the possibility of determining the position of objects adjacent to a vehicle that is equipped with an ultrasonic sensor.

With regard to further features or advantages of the use, reference is made to the description of the method, the driving assistance system and the vehicle, and vice versa.

A driving assistance system for a vehicle is also described, comprising a Ultrasonic sensor and a control unit for processing the data supplied by the ultrasonic sensor, the control unit being designed to carry out a method as described in detail above.

A driving support system can be understood in a manner known per se as an additional electronic device for a vehicle, in particular for a motor vehicle, which can serve to support the driver in certain driving situations. Safety aspects are often in the foreground here. In the present case, the driving assistance system is intended, in particular, to serve to improve collision prevention or a collision warning, which can come into play, for example, when parking or exiting a parking space. In this case, the driving assistance system can enable the surroundings of the vehicle to be observed by means of the ultrasonic sensor or the ultrasonic sensors, and thus warn of a collision with other vehicles, objects or people.

The driving assistance system comprises at least one ultrasonic sensor, that is to say one or a plurality of ultrasonic sensors, and also a control unit. The control unit can receive and evaluate the data supplied by the ultrasonic sensor or the ultrasonic sensors, so that the data can be converted into distances to obstacles, for example. Furthermore, amplitude curves or their changes can be evaluated in order to enable the position of the object to be determined or the relative position of the reflection point at which the ultrasonic radiation is reflected.

The driving assistance system can thus in particular be a parking aid and / or a maneuvering aid.

The data generated there can also be forwarded by the control unit to an information unit, such as a tone generator and / or a visual display. For example, the driving support system can use the ultrasonic sensor or the ultrasonic sensors to forward distance information or other information on the surroundings to a driver of a vehicle and thus prevent collisions or at least significantly reduce the risk of collisions occurring. Furthermore, the driving support system can initiate control interventions, for example through the control unit, in order to be able to allow, for example, autonomous driving, for example autonomous parking.

By providing an ultrasonic sensor as described above, an effective and reliable determination of the position of the object in relation to the vehicle can be made possible.

With regard to further features or advantages of the driving assistance system, reference is made to the description of the method, the use and the vehicle, and vice versa.

• 1 ein Fahrzeug, welches ein Fahrunterstützungssystem, mit mehreren Ultraschallsensoren aufweist; und
• 2 ein Diagramm darstellend eine winkelabhängige Sende und Empfangscharakteristik eine Ultraschallsensors.

Further advantages and advantageous configurations of the subject matter according to the invention are illustrated by the drawings and explained in the following description. It should be noted that the drawings are only of a descriptive nature and are not intended to restrict the invention in any way. Show it:

• 1 a vehicle having a driving assistance system with a plurality of ultrasonic sensors; and
• 2 a diagram showing an angle-dependent transmission and reception characteristic of an ultrasonic sensor.

1 shows a vehicle 10 according to an embodiment of the present invention in a plan view. The vehicle 10 is designed in the present case as a passenger car. The vehicle 10 includes a driving assistance system 12th . The driving support system 12th again comprises a control unit 14th possibly by an electronic control unit (ECU) of the vehicle 10 can be formed. It also includes the driving assistance system 12th at least one ultrasonic sensor 16 .

The present includes the driving support system 12th eight ultrasonic sensors 16 that distributed to the vehicle 10 are arranged. There are four ultrasonic sensors 16 at a front area 18th of the vehicle 10 and four ultrasonic sensors 16 at a stern area 20th of the vehicle 1 arranged. The ultrasonic sensors 16 are designed to do at least one object 22nd in a surrounding area 24 of the vehicle 10 capture. The ultrasonic sensors 16 serve in particular to establish a relative position between the object 22nd and the vehicle 10 to determine. The ultrasonic sensors 16 can, for example, at corresponding openings in the bumpers of the vehicle 10 be arranged. It can also be provided that the ultrasonic sensors 16 are concealed behind the bumpers.

The control unit 14th can thus read the data from the ultrasonic sensors 16 process and convert them into corresponding distance values. A control unit 14th can also issue or initiate control commands based on this data. In addition, it is provided that through the ultrasonic sensors 16 in combination with the control unit 14th the relative position of the object 22nd to the vehicle 10 can be determined. Only one or a plurality of the ultrasonic sensors can be used for this purpose 16 be used, with a position determination of the object 22nd preferred for every ultrasonic sensor 16 is carried out individually.

This possibility is based in particular on the following. With ultrasonic sensors 16 it occurs that ultrasonic waves are emitted over a certain angular range, both in a horizontal plane and in a vertical plane, corresponding to the respective opening angle. There is an angle-dependent amplitude of the radiated power.

This is in the 2 shown.

Shows in detail 2 a diagram in which on the X-axis the angular range in degrees in front of the ultrasonic sensor 16 is shown. In this regard, radiation emitted exactly along the sensor axis lies at an angle range of 0. The sound level is specified in db on the Y axis. Curve A shows an angle-dependent transmission and reception characteristic of the ultrasonic sensor in a vertical plane, and curve B shows an angle-dependent transmission and reception characteristic of the ultrasonic sensor in a horizontal plane. Furthermore, by the reference number 26th the horizontal opening angle of the ultrasonic sensor 16 and is indicated by the reference numeral 28 the vertical opening angle of the ultrasonic sensor 16 The values shown here are only intended to be exemplary and not restrictive.

It is thus shown that ultrasonic sensors 16 usually have an angle-dependent amplitude of the emitted radiation and accordingly also of the detected radiation. This angular dependency of the amplitude can be used in the further method for a position determination.

Such a method takes advantage of the fact that it is provided in summary that the ultrasonic sensor 16 in a moving vehicle 10 which is relative to the object 22nd moves while performing two consecutive measurements. In other words, successive echoes of the ultrasonic radiation are detected or recorded. This makes it possible for the vehicle to 10 relative to the object 22nd are at a different angle to each other.

Because the angle-dependent amplitude is at different relative positions of the vehicle 10 to the object 22nd and thus at different angles of the ultrasonic sensor 16 to the object 22nd is detected, can by comparing the amplitudes or amplitude curves obtained on the position of the object 22nd relative to the vehicle 10 getting closed. In other words, the change in amplitude is analyzed, the cause of which is the different position of the vehicle 10 or the ultrasonic sensor 16 to the object 22nd and thus the different angles of the vehicle 10 or the ultrasonic sensor 16 to the object 22nd is, whereby a position determination of the object 22nd relative to the vehicle 10 becomes possible.

1. a) Emittieren von Ultraschallstrahlung auf ein in einem Erfassungsbereich eines Ultraschallsensors 16 befindliches Objekt 22 zu einem Zeitpunkt t1, wenn sich das Fahrzeug 10 an einer ersten Position relativ zu dem Objekt 22 befindet;
2. b) Detektieren von in Verfahrensschritt a) emittierter und von dem Objekt 22 reflektierter Strahlung;
3. c) Emittieren von Ultraschallstrahlung auf das Objekt 22 zu einem Zeitpunkt t2, wobei t2 nach t1 liegt, und wobei sich das Fahrzeug 10 an einer zu der ersten Position verschiedenen zweiten Position relativ zu dem Objekt 22 befindet;
4. d) Detektieren von in Verfahrensschritt c) emittierter und von dem Objekt 22 reflektierter Strahlung;
5. e) Erfassen eines zeitlichen Verlaufs der Amplitude der in Verfahrensschritt b) und in Verfahrensschritt d) detektierten Strahlung; und
6. f) Bestimmen der Position des Objekts 22 relativ zu dem Fahrzeug 10 basierend auf einem Vergleich des zeitlichen Verlaufs der Amplitude der in Verfahrensschritt b) und in Verfahrensschritt d) detektierten Strahlung.

Such a method has in particular the following method steps:

1. a) emitting ultrasonic radiation onto a detection area of an ultrasonic sensor 16 located object 22nd at a time t1 when the vehicle is 10 at a first position relative to the object 22nd is located;
2. b) detecting emitted in method step a) and from the object 22nd reflected radiation;
3. c) emitting ultrasonic radiation onto the object 22nd at a point in time t2, where t2 is after t1, and where the vehicle is 10 at a second position relative to the object that differs from the first position 22nd is located;
4. d) detecting emitted in method step c) and from the object 22nd reflected radiation;
5. e) recording a time profile of the amplitude of the radiation detected in method step b) and in method step d); and
6. f) determining the position of the object 22nd relative to the vehicle 10 based on a comparison of the time profile of the amplitude of the radiation detected in method step b) and in method step d).

• g1) Emittieren von Ultraschallstrahlung auf ein in einem Erfassungsbereich eines Ultraschallsensors 16 befindliches Objekt 22 zu einem Zeitpunkt t3, wenn sich das Fahrzeug 10 an einer dritten Position relativ zu dem Objekt 22 befindet;
• g2) Detektieren von in Verfahrensschritt g1) emittierter und von dem Objekt 22 reflektierter Strahlung;
• g3) Emittieren von Ultraschallstrahlung auf das Objekt 22 zu einem Zeitpunkt t4, wobei t4 nach t3 liegt, und wobei sich das Fahrzeug 10 an einer zu der drittem Position verschiedenen vierten Position relativ zu dem Objekt befindet;
• g4) Detektieren von in Verfahrensschritt g3) emittierter und von dem Objekt 22 reflektierter Strahlung;
• g5) Aufzeichnen der relativen Position des Fahrzeugs 10 zu dem Objekt 22 bei den Verfahrensschritten g1) und g3); und
• g6) Aufzeichnen jeweils eines zeitlichen Verlaufs der Amplitude basierend auf der in Verfahrensschritt g2) und g4) detektierten Strahlung oder Aufzeichnen einer Veränderung der zeitlichen Verläufe der Amplitude basierend auf der in Verfahrensschritt g2) und g4) detektierten Strahlung.

In particular, the method or, in particular, the evaluation of the data can take place using a neural network. This should be trained before the real measurement in order to obtain a particularly effective measurement, for example by using the vehicle during a training session 10 guided on a guide on the object 22nd is moved along. A corresponding training step can have the following procedural steps:

• g1) emitting ultrasonic radiation onto one in a detection range of an ultrasonic sensor 16 located object 22nd at a time t3 when the vehicle is 10 at a third position relative to the object 22nd is located;
• g2) detecting emitted in method step g1) and from the object 22nd reflected radiation;
• g3) emitting ultrasonic radiation onto the object 22nd at a point in time t4, where t4 is after t3, and where the vehicle is 10 is at a fourth position relative to the object different from the third position;
• g4) detecting emitted in method step g3) and from the object 22nd reflected radiation;
• g5) recording the relative position of the vehicle 10 to the object 22nd in process steps g1) and g3); and
• g6) recording a temporal course of the amplitude based on the radiation detected in method step g2) and g4) or recording a change in the temporal course of the amplitude based on the radiation detected in method step g2) and g4).

List of reference symbols

10

vehicle

12th

Driving assistance system

14th

Control unit

16

Ultrasonic sensor

18th

Front area

20th

Stern area

22nd

object

24

Surrounding area

26th

horizontal opening angle

28

vertical opening angle

QUOTES INCLUDED IN THE DESCRIPTION

This list of the documents listed by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Patent literature cited

• DE 19541459 A1 [0004]
• DE 4001493 A1 [0005]
• US 2012/0293356 A1 [0006]
• US 5548512 A [0007]

Claims (10)

Method for determining the position of an object (22) relative to a vehicle (10) by means of ultrasonic radiation, comprising the method steps: a) emitting ultrasonic radiation onto an object (22) located in a detection range of an ultrasonic sensor (16) at a point in time t1 when the vehicle (10) is at a first position relative to the object (22); b) detecting ultrasonic radiation emitted in method step a) and reflected by the object (22); c) emitting ultrasonic radiation onto the object (22) at a point in time t2, wherein t2 is after t1, and wherein the vehicle (10) is at a second position relative to the object (22) that is different from the first position; d) detecting ultrasonic radiation emitted in method step c) and reflected from the object (22); e) recording a time profile of the amplitude of the ultrasonic radiation detected in method step b) and in method step d); and f) Determining the angle and / or the position of the object (22) relative to the vehicle (10) based on a comparison of the time profile of the amplitude of the ultrasonic radiation detected in method step b) and in method step d). Procedure according to Claim 1 , characterized in that method step f) takes place using a neural network. Procedure according to Claim 2 , characterized in that the method has the further method step before method step a): g) training the neural network using the method steps: g1) emitting ultrasonic radiation onto an object (22) located in a detection area of an ultrasonic sensor (16) to a Time t3 when the vehicle (10) is at a third position relative to the object (22); g2) detecting radiation emitted in method step g1) and reflected from the object (22); g3) emitting ultrasonic radiation onto the object (22) at a point in time t4, wherein t4 is after t3, and wherein the vehicle (10) is at a fourth position relative to the object (22) that is different from the third position; g4) detecting radiation emitted in method step g3) and reflected from the object (22); g5) recording the relative position of the vehicle (10) to the object (22) in method steps g1) and g3); and g6) recording a temporal course of the amplitude based on the radiation detected in method step g2) and g4) or recording a change in the temporal course of the amplitudes based on the radiation detected in method step g2) and g4). Procedure according to Claim 3 , characterized in that the vehicle (10) is guided along a guide and moved along the object (20) during method step g). Method according to one of the Claims 1 to 4th , characterized in that the method steps a) to d) are carried out according to a predetermined time frequency. Method according to one of the Claims 1 to 5 , characterized in that the method steps a) to d) are carried out adaptively in time based on at least one driving characteristic of the vehicle (10). Method according to one of the Claims 1 to 6th , characterized in that method steps a) to f) are carried out for a single ultrasonic sensor (16). Method according to one of the Claims 1 to 7th , characterized in that the method steps a) to f) are carried out for a plurality of ultrasonic sensors (16) and in each case separately for each of the ultrasonic sensors (16). Use of a method according to one of the Claims 1 to 8th for a parking assistance procedure or maneuvering assistance procedure. Driving support system for a vehicle (10), comprising an ultrasonic sensor (16) and a control unit (14) for processing the data supplied by the ultrasonic sensor (16), characterized in that the control unit (14) for performing a method according to one of the Claims 1 to 8th is designed.

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