Method for operating an ultrasonic sensor for a motor vehicle with a first and a second measuring mode, electronic computing device, ultrasonic sensor and driver assistance system

Abstract

Method for operating an ultrasonic sensor (5a) for a motor vehicle (1) with at least the ultrasonic sensor (5a), wherein an ultrasonic signal (8) is emitted into an environment (4) of the motor vehicle (1) by means of a transmitting device (6) of the ultrasonic sensor (5a) depending on an electrical excitation signal of an electronic computing device (10) of the ultrasonic sensor (5a) by means of a transmitting device (6) of the ultrasonic sensor (5a) depending on an electrical excitation signal of an electronic computing device (10) of the ultrasonic sensor (5a) and an echo signal (9) of the ultrasonic signal reflected by an object (3, 15, OB) in the environment (4) is received by a receiving device (7) of the ultrasonic sensor (5a),and wherein the ultrasonic sensor (5a) is operated in a first measurement mode for at least one first assistance function (12) of a driver assistance system (2) of the motor vehicle (1) and the ultrasonic sensor (5a) is operated in a second measurement mode different from the first measurement mode for at least one second assistance function (13) of the driver assistance system (2), characterized in that in the first measurement mode the received echo signal (9) is amplified with a first amplifier curve (V1) for evaluation of the received echo signal (9) and in the second measurement mode the echo signal (9) is amplified with a second amplifier curve (V2) different from the first amplifier curve (V1) for evaluation of the received echo signal (9).

Description

[0001] The invention relates to a method for operating an ultrasonic sensor for a motor vehicle, comprising at least one ultrasonic sensor. By means of a transmitting device of the ultrasonic sensor, an ultrasonic signal is emitted into the surroundings of the motor vehicle as a function of an electrical excitation signal from an electrical computing device of the ultrasonic sensor. An echo signal of the ultrasonic signal reflected by an object in the surroundings is received by a receiving device of the ultrasonic sensor. The ultrasonic sensor is operated in a first measuring mode for at least one first assistance function of a driver assistance system of the motor vehicle, and the ultrasonic sensor is operated in a second measuring mode, different from the first measuring mode, for at least one second assistance function of the driver assistance system that is different from the first assistance function.Furthermore, the invention relates to an electronic computing device, an ultrasonic sensor and a driver assistance system.

[0002] The present interest is particularly directed towards ultrasonic transducer devices, which can also be referred to as ultrasonic sensor devices, for motor vehicles. Such ultrasonic transducer devices can, for example, have multiple ultrasonic transducers or ultrasonic sensors, which can be arranged, for example, on the bumper of the motor vehicle. Such ultrasonic transducer devices are used, for example, in parking assistance systems that assist the driver when parking into a parking space. The ultrasonic transducer can be used to detect objects in the surrounding area and to determine the distance to the objects. The transmission power and reception sensitivity are calibrated during production. With the aim of object detection, they emit a respective ultrasonic signal, which is reflected by objects.The analysis of the received echoes of the ultrasonic signals then allows conclusions to be drawn about the position and type of the object. For example, the echoes or reflected ultrasonic signals can be used to distinguish between a tall and a short object.

[0003] Ultrasonic sensor devices are currently used primarily in parking assistance systems based on ultrasonic technology. In particular, the functions of the individual assistance systems are integrated into additional functions that differ from the classic parking process. For example, the ultrasonic sensors of the ultrasonic sensor device are also used in blind spot detection (BSD) systems. Especially with these ultrasonic blind spot assist systems, which are based on ultrasonic technology, it is difficult to reliably detect collision-relevant objects due to wind noise, for example.

[0004] DE 196 45 339 A1 discloses an ultrasonic parking assistance system. Such systems emit warning signals when an echo signal within a listening window exceeds a certain threshold. Previously, a listening window or the system's sensitivity was adjusted once based on fixed vehicle and / or road surface data. It is proposed to adjust the sensitivity, the listening window, or even the transmission pattern depending on changing dynamic vehicle or road surface data.

[0005] DE 10 2007 026 688 A1 relates to a method for functionally testing a distance measurement system on a vehicle with at least one ultrasonic sensor. During the functional test, the sensitivity of the sensor is temporarily increased to detect ground reflections, and the detected ground reflections are compared.

[0006] DE 10 2005 046 045 A1 discloses a method for controlling at least one object detection sensor on a vehicle to which multiple functions can access, wherein the sensor can be switched between multiple operating modes depending on the accessing function. The operating mode is selected by a coordinator, which selects the most suitable operating mode for the sensor based on an importance density function.

[0007] DE 10 2016 121 565 A1 discloses a sensor device for a vehicle with a sensor and a control device for switching the sensor device between a first and a second operating mode depending on a driving situation, wherein the associated driving situations are detected based on a speed and an acceleration of the vehicle.

[0008] The object of the present invention is to provide a method, an electronic computing device, an ultrasonic sensor and a driver assistance system by means of which the functionality of an ultrasonic sensor can be increased.

[0009] This object is achieved according to a method, an electronic computing device, an ultrasonic sensor and a driver assistance system according to the independent patent claims.

[0010] One aspect of the invention relates to a method for operating an ultrasonic sensor for a motor vehicle having at least one ultrasonic sensor. By means of a transmitting device of the ultrasonic sensor, an ultrasonic signal is emitted into an environment of the motor vehicle as a function of an electrical excitation signal from an electrical computing device of the ultrasonic sensor. An echo signal of the ultrasonic signal reflected by an object in the environment is received by a receiving device of the ultrasonic sensor. The ultrasonic sensor is operated in a first measuring mode for at least one first assistance function of a driver assistance system of the motor vehicle. The ultrasonic sensor is operated in a second measuring mode different from the first measuring mode for at least one second assistance function of the driver assistance system that is different from the first assistance function.

[0011] It is provided that in the first measuring mode, the received echo signal is amplified with a first amplifier curve for evaluating the received echo signal and in the second measuring mode, the echo signal is amplified with a second amplifier curve different from the first amplifier curve for evaluating the received echo signal.

[0012] This creates an amplifier curve adapted to each measuring mode of the ultrasonic sensor, which is particularly dependent on the object, distance, and position. In particular, the respective amplifier curve can be generated statically or at very low speeds, for example less than 10 kilometers per hour. For example, a parking assistance system can then be provided as the first assistance function and the ultrasonic sensor can be operated with an amplifier curve specially adapted for the parking mode. For example, a blind spot assistance function can be provided as the second assistance function, and an amplifier curve specially adapted to the blind spot assistance function can be used to amplify the echo signal. This enables improved detection with a greater range, particularly when the motor vehicle is in motion, for example with the blind spot assistance function.In particular, the corresponding raw data can then be specifically adapted to the range and the respective vehicle. This allows, for example, an ultrasonic sensor range of 8 meters to be achieved. This enables improved operation of the ultrasonic sensor with two measurement modes, increasing the functionality of the ultrasonic sensor, as it can be used for at least two assistance functions.

[0013] Preferably, it can be provided that at least one further assistance function can be carried out by means of the ultrasonic sensor, wherein at least one further amplifier curve is then provided for the further assistance function.

[0014] According to an advantageous embodiment, the first amplifier curve can be provided depending on a predetermined first detection range in the first measuring mode and / or the second amplifier curve can be provided depending on a predetermined second detection range in the second measuring mode. If, for example, the first measuring mode is a parking assistance function, the amplifier curve can be adapted accordingly to the required range of the parking assistance. In particular, for parking assistance functions, for example, the range can be set accordingly low, since a resolution in the range of 0 to 3 meters is particularly relevant. In particular, the corresponding amplifier curve can then be adapted to the range of, for example, 0 to 3 meters.

[0015] If, for example, the blind spot assistant is provided as a second measurement mode, a range of 1 to 8 meters is particularly relevant, as vehicles may be located within this range during blind spot detection. In particular, the second amplifier curve can then be adjusted accordingly to the required range for the blind spot assistant, specifically to 1 to 8 meters. This enables adaptation to the various assistance functions. In particular, the corresponding amplifier curves are then adjusted to the different measurement modes of the assistance functions. This allows the ultrasonic sensor to be improved and operated with high functionality using two measurement modes.

[0016] It has also proven advantageous to filter out ambient noise in the echo signal using the first amplifier curve and / or the second amplifier curve. Noise can occur particularly at high speeds. In particular, this noise depends on the corresponding speed. In particular, with a blind spot assistant, the noise can be expected to be correspondingly high when the vehicle is traveling at high speed. This can be filtered out using appropriate filtering methods to prevent misinterpretation of the echo signal. For example, with a parking assistance function, less noise can be expected since the vehicle is traveling at a low speed, particularly when the vehicle is parked. This can also be taken into account when generating the respective amplifier curves for the respective measurement mode.This enables improved operation of the ultrasonic sensor with two different measuring modes.

[0017] It is also advantageous if the first assistance function is provided as a parking assistance function and / or the second assistance function is provided as a blind spot assistance function. In particular, this allows for different measurement modes with different gain curves to be provided for the different assistance functions. This makes it possible to improve the operation of the two assistance functions, especially the parking assistant and the blind spot assistant, and thus realize highly functional operation of the ultrasonic sensor with two different measurement modes.

[0018] In a further advantageous embodiment, the first amplifier curve is provided by a first control unit of the electronic computing device, and the second amplifier curve is provided by a second control unit of the electronic computing device. This has the advantage that the respective amplifier curves can be generated by different control units. Thus, the respective amplifier curve can be generated independently of the other control unit. In particular, if, for example, the first control unit is provided for evaluation for a parking assistance function and the second control unit is provided for evaluation of the blind spot assistance function, the amplifier curves can be provided on the respective control units specifically provided for the assistance function, and the evaluation can be reliably carried out on the respective control unit.This results in independent evaluation of each echo signal in the ultrasonic sensor. This enables the ultrasonic sensor to operate in two different measurement modes for two different assistance functions.

[0019] It is also advantageous if, depending on a detected environmental condition in the surroundings of the motor vehicle, at least a first parameter value of the first amplifier curve and / or a second parameter value of the second amplifier curve is adapted to the detected environmental condition. In other words, the environmental condition can be determined using an additional sensor of the motor vehicle, for example. For example, a rain sensor or a temperature sensor can detect the wetness or the temperature of the environment. In particular, the propagation of the ultrasonic waves is also dependent on the environmental conditions. For example, in the case of high air humidity, the ultrasonic signal can be attenuated more strongly. In particular, by detecting the respective environmental condition, the amplifier curve can be adapted accordingly to this environmental condition.This allows for improved detection of the environment in both the first and second measurement modes. In particular, an amplitude or frequency of the ultrasonic signal can be adjusted to the environmental conditions as a parameter. Accordingly, an amplitude range or frequency range within the echo signal can be amplified using the amplifier curve depending on the environmental conditions.

[0020] According to a further advantageous embodiment, in the first measuring mode the evaluation can additionally be carried out with a further first amplifier curve which is different from the first amplifier curve and / or in the second measuring mode the evaluation can additionally be carried out with a further second amplifier curve which is different from the second amplifier curve. As a result, the assistance function can be carried out using a redundant amplifier curve. This leads to improved detection of the surroundings, since the echo signal is amplified with two different amplifier curves in the same measuring mode and thus, for example, objects which would not have been shown by the first amplifier curve or the second amplifier curve are shown by the respective additional amplifier curves.This allows for redundant detection within each measurement mode, resulting in improved detection performance in that mode. This results in improved operation of the ultrasonic sensor.

[0021] It has also proven advantageous if the first amplifier curve and / or the second amplifier curve are provided as a function of an expected object type and / or an expected distance to the object and / or an expected relative position of the object to the motor vehicle. In particular, if the first amplifier curve should be provided for a parking assistant, for example, it is important to be able to detect a road edge, for example. This road edge can then be taken into account as the object type, and the amplifier curve can be adapted to the object type accordingly. It is also possible, for example, for a blind spot assistant to detect another motor vehicle as the object type, and the amplifier curve can be adapted to the motor vehicle as the object type. Furthermore, the amplifier curve can be adapted to the corresponding distance.Particularly with the parking assistance function, for example, distances of 0 meters to 3 meters are of greater relevance. In particular, the first amplifier curve can then be adapted to this distance. For the blind spot assistance function, for example, distances of 1 meter to 8 meters are particularly relevant. In particular, the second amplifier curve can then be adapted to the respective distance of 1 to 8 meters. Furthermore, it can be provided that the amplifier curve is provided according to the expected relative positions of the object to the motor vehicle. This allows the object to be reliably detected within the surroundings of the motor vehicle. This leads to improved operation of the ultrasonic sensor with two different measuring modes.

[0022] Furthermore, it has proven advantageous if the first amplifier curve and / or the second amplifier curve are stored on a storage medium of the electronic computing device. In particular, it can be provided, for example, that the respective amplifier curves were determined in laboratory experiments or test experiments and saved on the storage medium. In this way, the respective amplifier curves can be made available on the storage medium for different situations and for different assistance functions. Depending on the corresponding assistance functions and, for example, depending on the environmental conditions, the corresponding amplifier curve on the storage medium can then be accessed. This allows the respective amplifier curve to be read out from the storage medium depending on the situation, and the respective echo signal can be amplified accordingly. This enables improved operation of the ultrasonic sensor.

[0023] A further aspect of the invention relates to an electronic computing device configured to perform the method according to the preceding aspect. It is provided that the method is performed on the electronic computing device.

[0024] Furthermore, the invention relates to a computer program product with program code means stored in a computer-readable medium in order to carry out the method according to one of the preceding aspects when the computer program product is processed on a processor of an electronic control unit.

[0025] Yet another aspect of the invention relates to an ultrasonic sensor with an electronic computing device according to the preceding aspect.

[0026] Yet another aspect of the invention relates to a driver assistance system with at least one ultrasonic sensor according to the preceding aspect. Particularly in the case of fully autonomous driving of the motor vehicle, the driver assistance system can also be referred to as an electronic vehicle guidance system.

[0027] The invention also relates to a motor vehicle with a driver assistance system according to the preceding aspect. The motor vehicle is designed, in particular, as a passenger car.

[0028] Advantageous embodiments of the method are considered to be advantageous embodiments of the electronic computing device, the ultrasonic sensor, and the driver assistance system. The electronic computing device, the ultrasonic sensor, and the driver assistance system have specific features that enable implementation of the method.

[0029] Further features of the invention emerge from the claims, the figures and the description of the figures. The features and combinations of features mentioned above in the description as well as the features and combinations of features mentioned below in the description of the figures and / or shown alone in the figures can be used not only in the respective combination specified, but also in other combinations or on their own, without departing from the scope of the invention. Thus, embodiments are to be regarded as encompassed and disclosed by the invention that are not explicitly shown and explained in the figures, but which arise from separate combinations of features from the explained embodiments and can be produced. Embodiments and combinations of features are also to be regarded as disclosed that therefore do not have all the features of an originally formulated claim.Furthermore, embodiments and combinations of features, in particular by the embodiments set out above, are to be regarded as disclosed which go beyond or deviate from the combinations of features set out in the references to the claims.

[0030] Examples of embodiments are explained below using schematic drawings.

[0031] Showing: Fig. 1 a schematic plan view of an embodiment of a motor vehicle with an embodiment of an ultrasonic sensor when performing a first assistance function; Fig. 2 a schematic plan view of an embodiment of a motor vehicle with an ultrasonic sensor in a second assistance function; and Fig. 3 a schematic diagram with two amplifier curves.

[0032] In the figures, identical or functionally identical elements are provided with the same reference symbols.

[0033] Fig. 1 shows a motor vehicle 1 according to an embodiment of the present invention. In the present exemplary embodiment, the motor vehicle 1 is embodied as a passenger car. The motor vehicle 1 comprises a driver assistance system 2. For example, the driver assistance system 2 can detect an object 3, 15, OB located in the surroundings 4 of the motor vehicle 1. In particular, the driver assistance system 2 can be used to determine a distance between the motor vehicle 1 and the object 3.

[0034] The driver assistance system 2 comprises at least one ultrasonic sensor device 5. The ultrasonic sensor device 5, in turn, has at least one ultrasonic sensor 5a. The ultrasonic sensor 5a comprises a transmitting device 6, by means of which at least one ultrasonic signal 8, in particular a plurality of ultrasonic signals 8, can be emitted. In the present case, purely by way of example, an ultrasonic sensor device 5 with an ultrasonic sensor 5a is configured in a front region of the motor vehicle 1. Furthermore, purely by way of example, a further ultrasonic sensor device 5 is arranged in a rear region of the motor vehicle 1. The ultrasonic sensor device 5 in the rear region has, purely by way of example, four ultrasonic sensors 5a. With the transmitting device 6, the ultrasonic signals 8 can be emitted within a predetermined detection range E or a predetermined angular range, by means of a membrane.The membrane is coupled, in particular, to a sound transducer element 11, by means of which electrical signals can be converted into ultrasonic signals 8 during the transmission process and the echo signals 9 can be converted into electrical signals during the reception process. For example, the sound transducer element 11 can be a piezo element.

[0035] Furthermore, the ultrasonic sensor device 5 comprises a receiving device 7, by means of which reflected ultrasonic signals can be received as echo signals 9, which were reflected by the object 3, 15, OB, in particular via the membrane. The receiving device 7 can therefore receive ultrasonic signals 9 reflected by the object 3, 15, OB as a received signal. Furthermore, the ultrasonic sensor device 5 can have a control device S, which can be formed, for example, by a microcontroller and / or a digital signal processor. The driver assistance system 2 further comprises a control device 10, which can be formed, for example, by an electronic control unit (ECU - electronic control unit) of the motor vehicle 1. The control device 10 is connected to the ultrasonic sensor device 5 for data transmission. The data transmission can take place, for example, via the data bus of the motor vehicle 1.

[0036] In particular, it can be provided that, for example, a parking assistant is provided by means of the first assistance function 12. The Fig. 1 shows the motor vehicle 1 in a traffic situation in which the motor vehicle 1 wishes to park in a parking space 14. The parking space 14 can be delimited, for example, by other motor vehicles as object OB and, for example, by a curb 15. In particular, it is possible for the parking space 14 to be detected or measured accordingly using the ultrasonic sensor device 5.

[0037] It is provided that the ultrasonic signal 8 is emitted into the environment 4 of the motor vehicle 1 by means of the transmitting device 6 of the ultrasonic sensor 5a as a function of the electrical excitation signal of the electrical computing device 10 of the ultrasonic sensor 5a, and the echo signal 9 of the ultrasonic signal reflected by the object 3, 15, OB in the environment 4 is received by the receiving device 7 of the ultrasonic sensor 5a. The ultrasonic sensor 5a is operated in a first measuring mode for the first assistance function 12 of the driver assistance system 2 of the motor vehicle 1, and the ultrasonic sensor 5a is operated in a second measuring mode different from the first measuring mode for the second assistance function 13 of the driver assistance system 2, which is different from the first assistance function 12.

[0038] It is intended that in the first measuring mode the received echo signal 9 is evaluated with a first amplifier curve V1 ( Fig. 3) is amplified and in the second measuring mode the echo signal 9 is amplified for the evaluation of the received echo signal 9 with a second amplifier curve V2 ( Fig. 3) is reinforced.

[0039] In particular, Fig. 1 shows how the first assistance function 12 can be carried out with the ultrasonic sensor 5a. For this purpose, it is provided in particular that the received echo signal 9, in particular of the parking space 14, is amplified with the first amplifier curve V1 for evaluating the received echo signal 9. In particular, it can be provided that the first amplifier curve V1 is provided depending on a predetermined first detection range R1 in the first measuring mode. In particular, the first detection range R1 during the first assistance function, i.e. the parking assistance function, can be, for example, between 0 and 3 meters. In particular, the first amplifier curve V1 is then specifically adapted for this first detection range R1, in particular between 0 and 3 meters. As a result, the ultrasonic sensor 5a can be operated reliably for the first assistance function 12.

[0040] In particular, it can be provided that ambient noise in the echo signal 9 is filtered out by means of the first amplifier curve V1 and / or the second amplifier curve V2. In particular, ambient noise, for example due to wind or the vehicle's own speed, can also be detected by the ultrasonic sensor 5a. In particular, it can be provided that this ambient noise is filtered out. In particular, the ambient noise depends on the vehicle's own speed. In particular, for example, in a parking assistance system as the first assistance function 12, this ambient noise can be filtered out according to the speeds that can be expected during the parking function. The same applies, for example, to the blind spot assistance function as the second assistance function 13.In particular, at higher speeds, which can occur with the blind spot assistance function, other filtering measures are necessary to filter out this ambient noise.

[0041] Furthermore, it can be provided, in particular, that the first amplifier curve V1 is provided by a first control unit 16 of the electronic computing device 10, and the second amplifier curve V2 is provided by a second control unit 17 of the electronic computing device 10. This has the advantage that the respective amplifier curves V1, V2 can be generated by different control units 16, 17. Thus, the respective amplifier curve V1, V2 can be generated independently of the respective control units 16, 17.In particular, if, for example, the first control unit 16 is provided for evaluation for a parking assistance function and the second control unit 17 is provided for evaluation of the blind spot assistance function, the amplifier curves V1, V2 can be provided on the respective control units 16, 17 specifically provided for the respective assistance function 12, 13, and the evaluation can be reliably carried out on the respective control unit 16, 17. This leads to an independent evaluation of the respective echo signal 9 in the ultrasonic sensor 5a. This enables the operation of the ultrasonic sensor 5a with two different measuring modes for at least two different assistance functions 12, 13.

[0042] Furthermore, it can be provided in particular that, depending on a detected environmental condition in the environment 4 of the motor vehicle 1, at least a first parameter value of the first amplifier curve V1 and / or a second parameter value of the second amplifier curve V2 is adapted to the detected environmental condition. In other words, the environmental condition can, for example, be determined using an additional sensor of the motor vehicle 1. For example, a rain sensor or a temperature sensor can detect the wetness or the temperature of the environment 4. In particular, the propagation of the ultrasonic waves is also dependent on the environmental conditions. For example, in the case of high air humidity, the ultrasonic signal 8 can be attenuated more strongly. In particular, by detecting the respective environmental condition, the respective amplifier curve V1, V2 can be adapted accordingly to this environmental condition.This enables improved detection of the environment 4 in both the first measurement mode and the second measurement mode. In particular, an amplitude A (. Fig. 3) or a frequency of the ultrasonic signal 8 can be adapted to the environmental conditions. Accordingly, an amplitude range or a frequency range within the echo signal 9 can be amplified using the amplifier curve V1, V2 depending on the environmental conditions.

[0043] In particular, it can be provided that in the first measuring mode the evaluation is additionally carried out with a further first amplifier curve which is different from the first amplifier curve V1. As a result, the respective assistance function 12, 13 can be carried out by means of a redundant amplifier curve. This leads to improved detection of the environment 4, since the echo signal 9 is amplified within a receive mode with two different amplifier curves and thus, for example, objects 3, 15, OB, which would not have been shown, for example, by the first amplifier curve V1 or the second amplifier curve V2, are shown by the further amplifier curves. In this way, the detection can be carried out redundantly in a simple manner within the respective measuring mode, which leads to an improvement in the detection in the respective measuring mode. This results in improved operation of the ultrasonic sensor 5a.

[0044] Preferably, it can be provided that the first amplifier curve V1 is provided as a function of an expected object type, for example the curb 15 or the object OB, and / or an expected distance A1 to the object OB, 15 and / or an expected relative position of the object OB, 15 to the motor vehicle 1.

[0045] Furthermore, it can be provided that the first amplifier curve V1 and / or the second amplifier curve V2 are stored on a storage medium 18 of the electronic computing device 10. In particular, it can be provided, for example, that the respective amplifier curves V1, V2 were determined in laboratory experiments or test experiments and were stored on the storage medium 18. Thus, the respective amplifier curves V1, V2 can be provided on the storage medium 18 for different situations and for different assistance functions 12, 13. Depending on the corresponding assistance functions 12, 13 and, for example, depending on the environmental conditions, the corresponding amplifier curve V1, V2 on the storage medium 18 can then be accessed. As a result, the respective amplifier curve V1, V2 can be read out from the storage medium 18 depending on the situation, and the respective echo signal 9 can be amplified accordingly.This enables improved operation of the ultrasonic sensor 5a.

[0046] Fig. 2 shows a schematic view of the motor vehicle 1 according to Fig. 1 in another situation. In particular, the Fig. 2 the motor vehicle 1, wherein the driver assistance system 2 in particular carries out the second assistance function 13 by means of the ultrasonic sensor device 5 or with the ultrasonic sensors 5a. In particular, in the Fig. 2, the second assistance function 13 is designed as a blind spot assistance function. In particular, it is provided that the second amplifier curve V2 is provided in the second measuring mode depending on a predetermined second detection range R2. Furthermore, particularly in the second measuring mode, the evaluation can additionally be carried out with a further second amplifier curve, which is different from the second amplifier curve V2.

[0047] In particular, it is provided that the second amplifier curve V2 is implemented depending on the expected object type, which in this example may be another motor vehicle, for example. In particular, the second amplifier curve V2 can also be provided depending on an expected distance A2 from the object OB and / or an expected relative position of the object OB to the motor vehicle 1.

[0048] In other words, according to Fig. 1, the echo signal 9 is amplified by the ultrasonic sensor device 5 or by the ultrasonic sensors 5a with the first amplifier curve V1, so that in particular the parking space 14 can be detected more effectively. According to Fig. 2, the object OB is detected by the ultrasonic sensor device 5 or by the ultrasonic sensors 5a, wherein, in particular, the echo signal 9 is amplified by the second amplifier curve V2. This enables the ultrasonic sensor 5a to be operated with two different measurement modes in a highly functional manner. In particular, the measurement modes are different from one another and are enhanced by the different amplifier curves V1, V2. This enables highly functional operation of the ultrasonic sensors 5a.

[0049] Fig. Figure 3 shows a schematic diagram with the amplifier curves V1, V2. The ordinate shows the amplitude A of the echo signal 9 and the abscissa shows the gain V. In particular, the Fig. 3, that the amplifier curves V1, V2 are different amplifier curves V1, V2. In particular, in the first measurement mode, which can be, for example, the parking assistance function, the first amplifier curve V1 is applied. In particular, in the second measurement mode, which can be, for example, the blind spot assistance function, the second amplifier curve V2 can be applied. Fig. Figure 3 shows that the different amplifier curves V1, V2 are applied, especially when the amplitudes A of the received echo signal 9 differ. This is due to the fact that the ranges R1, R2, in particular, are different for the different assistance functions 12, 13, resulting in different amplitudes A within the echo signal 9.

[0050] In particular, the method according to the invention can reduce true positive and false warnings. Furthermore, it can be used to create better filters for rain, spray, ground reflections, and wind noise. The amplifier curve V1, V2 is specifically adjusted for later system conditions. Specific operating points are selected. The aim is to achieve a defined amplitude level over the distance and degree deviation from the sensor axis using a 75-millimeter tube, particularly during laboratory tests to generate the amplifier curves V1, V2. This could then, for example, also be specifically adapted for the blind spot assistant, since even a vehicle contour, for example of the object OB according to Fig. 2, even at 160 kilometers per hour and, for example, 8 meters away, it would be recognizable as distance A2.

[0051] In particular, during the development of the ultrasonic sensor 5a, a specific amplifier curve V1, V2 is created for each measurement mode, which is highly dependent on the object, distance, and position. This occurs particularly statically or at very low speeds (less than 10 kilometers per hour). A separate amplifier curve V2 is created specifically for the blind spot assist functions in order to better detect vehicles such as cars, trucks, motorcycles, bicycles, or the like while driving and thus achieve a greater distance range R2. In this case, the raw data would be specifically adapted to the range R2 and the vehicles or objects OB. This makes it possible to achieve a range of, for example, 8 meters, particularly with the parking assistance function and the blind spot assist function.

[0052] In particular, the method can then also provide a specific amplifier curve V1, V2 for the parking assistance function. In particular, the main focus can be on the curb 15, which is often located in the parking space 14.

Claims

[1] Method for operating an ultrasonic sensor (5a) for a motor vehicle (1) with at least the ultrasonic sensor (5a), wherein by means of a transmitting device (6) of the ultrasonic sensor (5a) an ultrasonic signal (8) is emitted into an environment (4) of the motor vehicle (1) as a function of an electrical excitation signal of an electronic computing device (10) of the ultrasonic sensor (5a), and an echo signal (9) of the ultrasonic signal reflected by an object (3, 15, OB) in the environment (4) is received by a receiving device (7) of the ultrasonic sensor (5a),and wherein the ultrasonic sensor (5a) is operated in a first measuring mode for at least one first assistance function (12) of a driver assistance system (2) of the motor vehicle (1), and the ultrasonic sensor (5a) is operated in a second measuring mode different from the first measuring mode for at least one second assistance function (13) of the driver assistance system (2) that is different from the first assistance function (12), characterized by that in the first measuring mode the received echo signal (9) is amplified with a first amplifier curve (V1) for evaluating the received echo signal (9) and in the second measuring mode the echo signal (9) is amplified with a second amplifier curve (V2) different from the first amplifier curve (V1) for evaluating the received echo signal (9). [2] Method according to claim 1, characterized bythat the first amplifier curve (V1) is provided depending on a predetermined first detection range (R1) in the first measuring mode and / or the second amplifier curve (V2) is provided depending on a predetermined second detection range (R2) in the second measuring mode. [3] Method according to one of the preceding claims, characterized by that ambient noise in the echo signal (9) is filtered out by means of the first amplifier curve (V1) and / or by means of the second amplifier curve (V2). [4] Method according to one of the preceding claims, characterized by that the first assistance function (12) is provided as a parking assistance function and / or the second assistance function (13) is provided as a blind spot assistance function. [5] Method according to one of the preceding claims, characterized bythat the first amplifier curve (V1) is provided by means of a first control unit (16) of the electronic computing device (10) and the second amplifier curve (V2) is provided by means of a second control unit (17) of the electronic computing device (10). [6] Method according to one of the preceding claims, characterized by that, depending on a detected environmental condition in the surroundings (4) of the motor vehicle (1), at least a first parameter value of the first amplifier curve (V1) and / or a second parameter value of the second amplifier curve (V2) is adapted to the detected environmental condition. [7] Method according to one of the preceding claims, characterized bythat in the first measuring mode the evaluation is additionally carried out with a further first amplifier curve which is different from the first amplifier curve (V1) and / or in the second measuring mode the evaluation is additionally carried out with a further second amplifier curve which is different from the second amplifier curve (V2). [8] Method according to one of the preceding claims, characterized by that the first amplifier curve (V1) and / or second amplifier curve (V2) is provided as a function of an expected object type and / or an expected distance to the object (3, 15, OB) and / or an expected relative position of the object (3, 15, OB) to the motor vehicle (1). [9] Method according to one of the preceding claims, characterized by that the first amplifier curve (V1) and / or second amplifier curve (V2) is stored on a storage medium (18) of the electronic computing device (10). [10] Electronic computing device (10) which is designed to carry out the method according to one of claims 1 to 9. [11] Ultrasonic sensor (5a) with an electronic computing device (10) according to claim 10. [12] Driver assistance system (2) with at least one ultrasonic sensor (5a) according to claim 11.

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