阅读说明：本技术 用于基于回声的环境检测的联网声学传感器单元 (Networked acoustic sensor units for echo-based environment detection ) 是由 C·尤哈斯 于 2019-11-06 设计创作，主要内容包括：本发明涉及一种用于基于回声的环境检测的声学传感器单元(10),所述声学传感器单元包括：发送单元(11),所述发送单元设置用于发射声学信号(100)；通信接口(12)；和控制电子设备(13),所述控制电子设备设置用于,通过所述通信接口(12)输出信号以便将信息发送到另外的声学传感器单元(20,30),以及通过所述通信接口(12)从所述另外的声学传感器单元(20,30)接收信号。在此,所述声学传感器单元(10,20,30)通过总线或网络节点(40)彼此连接或与中央控制单元连接。(The invention relates to an acoustic sensor unit (10) for echo based environment detection, comprising: a transmitting unit (11) arranged for transmitting an acoustic signal (100); a communication interface (12); and control electronics (13) arranged to output signals via the communication interface (12) for transmitting information to a further acoustic sensor unit (20, 30), and to receive signals from the further acoustic sensor unit (20, 30) via the communication interface (12). The acoustic sensor units (10, 20, 30) are connected to each other or to a central control unit via a bus or a network node (40).)

1. An acoustic sensor unit (10) for echo based environment detection, the acoustic sensor unit comprising:

a transmitting unit (11) which is provided for transmitting an acoustic signal (100),

a communication interface (12), and

control electronics (13) provided for,

outputting a signal via the communication interface (12) in order to transmit information to a further acoustic sensor unit (20, 30), and

receiving signals from the further acoustic sensor unit (20, 30) through the communication interface (12).

2. The acoustic sensor unit (1) according to claim 1, characterized in that the control electronics (13) are provided for,

outputting a control signal via the communication interface (12) in order to manipulate the further acoustic sensor unit (20, 30) to provide sensor information describing characteristics of the acoustic signal (100) when the acoustic signal is received by the further acoustic sensor unit (20, 30),

receiving the sensor information through the communication interface (12),

generating object information based on characteristics of the emitted acoustic signal (100) and based on the sensor information, the object information describing characteristics of: the acoustic signal (100) is reflected on the object,

transmitting the object information through the communication interface (12).

3. The acoustic sensor unit (1) according to claim 2, characterized in that it is arranged to, in response to a start signal received via the communication interface (12):

transmitting the acoustic signal (100) by the transmitting unit,

a control signal is output through the communication interface,

receiving the sensor information through the communication interface (12),

generating the object information, an

-sending said object information via said communication interface (12).

4. The acoustic sensor unit (1) according to any one of the preceding claims, characterized in that the communication interface (12) provides a power line communication providing a voltage supply of the acoustic sensor unit (1).

5. The acoustic sensor unit (1) according to any one of the preceding claims, characterized in that the communication interface (12) is an ethernet interface.

6. The acoustic sensor unit (1) according to any one of the preceding claims, characterized in that the control unit (13) is arranged to send such information transmitted via the communication interface together with addressing information, and/or

-receiving, via said communication interface (13), the following information: the information has addressing information related to the acoustic sensor unit (1).

7. The acoustic sensor unit (1) according to any one of the preceding claims, characterized in that the control unit (13) is provided for generating the object information also on the basis of arrangement information, which describes an arrangement of the further acoustic sensor unit (20, 30) with respect to the acoustic sensor unit (1), wherein the arrangement information is preferably received via the communication interface (12).

8. The acoustic sensor unit (1) according to any one of the preceding claims,

the transmitting unit (11) is provided for receiving acoustic signals of the further acoustic sensor units (20, 30), and

the control electronics (13) are provided for receiving a control signal of the further acoustic sensor unit (20, 30) via the communication interface (12) and, in response to the reception of the control signal, for generating sensor information on the basis of the received acoustic signal of the further acoustic sensor unit (20, 30) and for transmitting the sensor information via the communication interface (12), the sensor information describing a property of the received acoustic signal.

9. Sensor system comprising at least two acoustic sensor units (10, 20, 30) according to any of the preceding claims, wherein the sensor system further comprises a central control unit (60) arranged for receiving object information of the acoustic sensor units (10, 20, 30).

10. Sensor system according to claim 8, wherein the acoustic sensor units (10, 20, 30) are connected by a bus or a network node (40).

Technical Field

The present invention relates to an acoustic sensor unit for echo based environment detection and a related system for echo based environment detection.

Background

Current ultrasonic sensors are operated by a central electronic control unit (also referred to as ECU). For this purpose, each of the ultrasonic sensors of the sensor system is connected to the central electronic control unit by a cable harness belonging to the ultrasonic sensor. However, this results in a large overhead for wiring the ultrasonic sensor. In a sensor system in which, for example, 12 ultrasonic sensors are arranged on a vehicle, a wire of 70m is usually required in order to connect the ultrasonic sensors with a central electronic control unit. The resulting long propagation path results in systems comprising ultrasonic sensors generally having slow response times, which are caused on the one hand by the necessary signal propagation times and on the other hand by the response times of the central control unit.

Disclosure of Invention

The acoustic sensor unit for echo based environment detection according to the present invention comprises: a transmitting unit arranged to transmit an acoustic signal; a communication interface; and control electronics arranged to output signals via the communication interface for transmitting information to the further acoustic sensor unit and to receive signals from the further acoustic sensor unit via the communication interface.

The acoustic sensor unit is therefore provided for transmitting signals directly to the further acoustic sensor unit without the signals being transmitted by the central electronic control unit. Thus an acoustic sensor unit is achieved which is capable of communicating directly with other acoustic sensor units. Thereby shortening the signal propagation time and enabling a reduction in wiring overhead. Thus, in particular in sensor systems, it is not necessary: the acoustic sensor unit is connected to the central electronic control unit via its own wiring harness (leitsustrang).

The acoustic sensor unit is in particular an ultrasonic sensor. Therefore, the acoustic signal is preferably an ultrasonic signal. The communication interface is an interface that enables the acoustic sensor unit to send and receive electrical signals. For this purpose, the communication interface is preferably connected to an electrical conductor, via which signals are conducted. The signal is here a communication signal.

The control electronics are preferably application specific integrated circuits, ASIC for short. The communication interface is preferably integrated into the control electronics. The further acoustic sensor unit is a sensor unit which is preferably of the same construction as the acoustic sensor unit.

Thus, communication between two acoustic sensor units is enabled by the acoustic sensor units. It is therefore not necessary: the central electronic control unit controls the synchronization of the individual acoustic sensor units or also combines the signals of the individual acoustic sensor units.

The dependent claims show preferred embodiments of the invention.

Preferably, the control electronics are arranged to: outputting a control signal via the communication interface in order to manipulate the further acoustic sensor unit to provide sensor information describing characteristics of the acoustic signal when received by the further acoustic sensor unit; receiving sensor information through a communication interface; generating object information based on the characteristics of the transmitted acoustic signal and the sensor information, the object information describing characteristics of an object on which the acoustic signal is reflected; and transmitting the object information through the communication interface. Thus, the acoustic sensor unit is adapted to control echo based environment detection. In this way, the control signal is particularly suitable for operating the further acoustic sensor unit to receive the acoustic signal emitted by the transmitting unit. The acoustic signal is typically reflected to the further sensor unit after reflection on the object, whereby echo-based environmental detection may be performed by transmitting the acoustic signal by the acoustic sensor unit and receiving the acoustic signal by the further acoustic sensor unit.

The control signal preferably comprises information relating to the transmission time or modulation of the acoustic signal. The sensor information describes characteristics of the acoustic signal when the acoustic signal is received by the further acoustic sensor unit. The characteristic may be any characteristic of the acoustic signal, in particular a signal propagation time between transmission by the transmitting unit and reception by the further acoustic sensor unit, a frequency or a frequency variation process of the acoustic signal when the acoustic signal is received by the further acoustic sensor unit, or a signal strength of the acoustic signal when the acoustic signal is received by the further acoustic sensor unit.

The sensor information is received by the acoustic sensor unit and processed by the control electronics. This results in object information which describes the properties of the object on which the acoustic signal is reflected before it is received by the further acoustic sensor unit. In this way, for example, the distance between the acoustic sensor unit and the object is calculated by the control electronics and provided as object information. Preferably, the control electronics use more information for this purpose. In this way, information relating to the position of the further acoustic sensor unit is preferably stored in the control electronics, and the object information is preferably calculated on the basis of the saved position of the further acoustic sensor unit.

Further preferably, the acoustic sensor unit is provided for: the control signal is transmitted to a plurality of further acoustic sensor units, the relevant sensor information is received from the plurality of further acoustic sensor units, respectively, and the object information is generated based on the sensor information of the plurality of further acoustic sensor units.

The object information is in particular the position (Lage) of the object relative to the acoustic sensor unit, the distance of the object from the acoustic sensor unit or the relative velocity of the object relative to the acoustic sensor unit. It is further preferred that the object information comprises properties related to the object, describing for example the structure of the object. The object information is transmitted, i.e. provided, via the communication interface. Therefore, not only sensor information is output by the acoustic sensor unit, but also signal processing is performed in the acoustic sensor unit. Unnecessary signal propagation time can be prevented and object information can be provided quickly.

Further preferably, the acoustic sensor unit is provided for: transmitting an acoustic signal through a transmitting unit in response to a start signal received through a communication interface; outputting a control signal through a communication interface; receiving sensor information through a communication interface; generating object information and transmitting the object information through the communication interface. A single measurement cycle can be triggered via the communication interface for generating the object information. Unnecessary measurement processes for generating the object information can thus be avoided, wherein the object information is provided in particular only when required.

It is also advantageous that the communication interface provides power line communication (Powerline-kommunik) providing a voltage supply to the acoustic sensor unit. In this way, the communication interface has in particular only two connection contacts, via which both the voltage supply and the transmission of signals to or from the communication interface can be carried out. Optionally, the communication interface has an additional ground connection. The wiring effort required when using the acoustic sensor unit is thus further reduced.

It is also advantageous if the communication interface is a network interface. The communication interface is in particular an ethernet interface. This means that the communication interface supports network protocols. As such, the communication interface supports, among other things, the 100-Base-T1 or 1000-Base-T1 protocols. Thus providing a communication interface with sufficient speed to communicate with further acoustic sensor units. Also, commercially available components may be used in signal routing.

Preferably, the communication interface is a power line communication interface, wherein the communication interface supports a network protocol. By means of this communication interface, the network signal is preferably converted into a power line communication, wherein the signal transmitted by the power line communication preferably comprises all the information required for the relevant network protocol. Thus, for example, it is possible to: the acoustic sensor unit is connected to the network only by power line communication, wherein in such a system the signal emitted by the acoustic sensor unit by power line communication is preferably converted again at the network node into a network signal supported by the network node at a connection of the network node provided for the network node. The acoustic sensor unit therefore requires a particularly low wiring complexity, wherein at the same time the tested signal routing of the network nodes can be used.

It is also advantageous if the control unit is provided for: such information is transmitted together with addressing information via the communication interface and/or received with addressing information related to the acoustic sensor unit via the communication interface. It is thus possible to realize: the acoustic sensor unit can transmit information to selected further acoustic sensor units in a targeted manner or can receive information addressing the acoustic sensor unit in a targeted manner. Thus, for example, it is possible to realize: by means of the acoustic sensor units, only selected further acoustic sensor units are excited by means of the control signal to transmit sensor information to the acoustic sensor units.

Further preferably, the control unit also generates object information based on arrangement information describing an arrangement of the further acoustic sensor relative to the acoustic sensor unit, wherein the arrangement information is preferably received via the communication interface. In this case, the arrangement information is transmitted to the acoustic sensor units either from the further acoustic sensor units or from the central control unit. In this case, it is preferred that possible arrangements of the further acoustic sensor units with respect to the acoustic sensor units are stored in the control electronics and that a selection is made from the possible arrangements by means of the arrangement information in order to select the actual arrangement of the further acoustic sensor units with respect to the acoustic sensor units. Such arrangement information enables particularly accurate calculation of the object information. In this way, a geometric calculation can be realized, which is carried out based on the arrangement of the further acoustic sensor unit relative to the acoustic sensor unit, in particular based on the position of the acoustic sensor unit and the further acoustic sensor unit on the vehicle.

It is also advantageous if the transmitting unit is provided for receiving acoustic signals of the further acoustic sensor unit, and the control electronics are provided for receiving control signals of the further acoustic sensor unit via the communication interface and, in response to the reception of the control signals, generating sensor information on the basis of the received acoustic signals of the further acoustic sensor unit, the sensor information describing a property of the acoustic signals received by the acoustic sensor unit and previously emitted by the further acoustic sensor unit. The control electronics are preferably also provided for transmitting sensor information via the communication interface. Therefore, the acoustic sensor unit is preferably arranged to provide the following same functions: this same function is also provided by the further acoustic sensor unit. The acoustic sensor unit and the further acoustic sensor unit are therefore preferably embodied identically in construction. Accordingly, the measurement process for generating the object information can also be controlled by a further acoustic sensor unit, wherein the further acoustic sensor unit is provided with the sensor information by the acoustic sensor unit.

The sensor system according to the invention comprises at least two acoustic sensor units according to any of the preceding claims, wherein the sensor system further comprises a central control unit arranged for receiving object information of the acoustic sensor units. In this case, the start signal is particularly preferably provided by the central control unit and transmitted to one of the acoustic sensor units. Thus, a further unit is provided by the central control unit, by which further calculations are performed, for example based on the object information provided by the acoustic sensor unit. Thus, the costly and complex calculations need not be performed by each individual one of the acoustic sensor units, but may be centralized.

Preferably, the acoustic sensor units are connected by a bus or a network node. Here, the network node is preferably a Hub (Hub) or a Switch (Switch). The hub or the switch here also preferably comprises a converter which converts the power line communication used by the acoustic sensor units into communication signals supported by the switch or the hub. Preferably, each of the acoustic sensor units is assigned a network address or a bus address.

Drawings

Embodiments of the present invention are described in detail below with reference to the accompanying drawings. In the drawings:

figure 1 is an acoustic sensor unit according to one embodiment of the invention,

figure 2 is a schematic diagram of a communication interface supporting power line communication,

figure 3 is a diagram of a sensor system according to one embodiment of the present invention,

FIG. 4 is a schematic diagram of a first step of a measurement cycle controlled by an acoustic sensor unit, and

fig. 5 is a second step of the measurement cycle controlled by the acoustic sensor unit.

Detailed Description

Fig. 1 shows an acoustic sensor unit 10 for echo-based environmental detection according to an embodiment of the present invention. The acoustic sensor unit 10 comprises a transmitting unit 11, a communication interface 12 and control electronics 13. The control electronics 13 are here an integrated circuit. The communication interface 12 is integrated into the integrated circuit and thus into the control electronics 13.

The transmitting unit 11 is arranged to emit an acoustic signal 100 when it is excited for this purpose by the control electronics 13. The acoustic signal 100 is, for example, an ultrasonic signal. The transmitting unit 11 is an electroacoustic transducer.

The control electronics 13 are arranged to output signals via the communication interface 12 in order to transmit information to the further acoustic sensor unit 20, 30 and to receive signals from the further acoustic sensor unit 20, 30 via the communication interface. This means that the acoustic sensor unit 10 is arranged for communication with further acoustic sensor units 20, 30.

Power line communication is provided through communication interface 12. In this case, a voltage supply for the acoustic sensor unit 10 is provided via the communication interface 12. An exemplary communication interface 12 is shown in fig. 2. In fig. 2, the communication interface 12 is connected to a further communication interface 50, via which a supply voltage for power line communication is provided. In particular the network node 40 or the central control unit 60 comprises the further communication interface 50. Therefore, optionally, further acoustic sensor units 20, 30 can also be coupled between the further communication interface 50 and the communication interface 12 of the acoustic sensor unit 10.

The communication interface 12 shown in fig. 2 has an input connection 14 with a first pole and a second pole. Optionally, the communication interface 12 has a third connection, through which the communication interface 12 or the acoustic sensor unit 10 is connected to ground. The first and second poles of the input connection are each coupled to the voltage supply unit 16 via an inductance. The voltage supplied via the input connection 14, in particular a direct voltage with a modulated (aufmodulert) signal, is converted by the voltage supply unit 16 into a supply voltage, which is in turn supplied as a supply voltage to the electronic components of the acoustic sensor unit 10. The electronic components of the acoustic sensor unit 10 are shown in fig. 1 as a load 17. The load 17 here comprises, in particular, the control electronics 13 and the transmission unit 11.

In the example described, a direct voltage is output by the further communication interface 50, to which direct voltage the signal is modulated. To decouple the signal from the supply voltage, the communication interface 12 comprises an inductive coupling element 15 in which an input coil is inductively coupled with an output coil. Each connection of the input coil is coupled to a respective pole of the input connection 14 via a respective capacitor. Thus, only the signal modulated onto the direct voltage is transmitted via the inductive coupling element 15 to the transmitting and receiving electronics 19 coupled to the connection of the output coil. The signal component is a signal received via the communication interface 12 for communication with a further acoustic sensor unit 20, 30 or with the control unit 60. Conversely, the signal can also be modulated by the transmitting and receiving electronics 19 onto the direct voltage applied to the input connection 14 in order to transmit the signal to the central control unit 60 or to the further acoustic sensor units 20, 30.

The structure of the further communication interface 50 substantially corresponds to the structure of the communication interface 12. Here, however, the voltage feeding unit 52 is arranged at the position of the voltage supply unit 16. The voltage supply unit 52 is coupled to and supplied by an external voltage supply, for example, with a 12V dc voltage. The supply voltage provided for the acoustic sensor unit 10 is supplied via an output connection 51 of the further communication interface 50 via a voltage supply unit 52, which output connection is coupled to both poles of the input connection 14 of the communication interface 12. Furthermore, the electronics 53 of the central control unit 60 or of the network node 40 are also supplied with an operating voltage by means of the voltage supply unit 52. In correspondence with the transmitting and receiving electronics 19 of the communication interface 12, transmitting and receiving electronics 54 are also arranged in the further communication interface 50, which enable the network node 40 or the central control unit 60 to modulate the desired signal onto the supply voltage. In this way, for example, a direct voltage (for example of 12V) is provided via the poles of the output connection 51, to which direct voltage the signal to be transmitted to the acoustic sensor unit 10 is modulated by means of the transmitting and receiving electronics 54 of the further communication interface 50 and the inductive coupling unit 55 of the further communication interface 50. In a corresponding manner, the transmission and reception electronics 54 of the further communication interface 50 can also receive signals modulated by the acoustic sensor unit 10 on the direct voltage by means of the communication interface 12.

The communication interface 12 is also a network interface in particular. In this case, the communication interface 12 is connected to the central control unit 60 and to the further acoustic sensor units 20, 30, in particular via the network node 40. The network node 40 is in particular a switch or hub coupled to a central control unit 60.

In fig. 3, a sensor system 200 according to an embodiment of the invention is shown. The sensor system 200 here comprises a plurality of acoustic sensor units 10, 20, 30, of which six are shown by way of example in fig. 3. One of the plurality of acoustic sensor units is the acoustic sensor unit 10. In addition to the acoustic sensor unit 10, the sensor system 200 comprises a first further acoustic sensor unit 20 and a second further acoustic sensor unit 30. Each of the acoustic sensor units 10, 20, 30 is connected to a network node 40. The network node 40 is also connected to a central control unit 60. In the exemplary embodiment, network node 40 is a hub. This means that each signal sent from the acoustic sensor unit 10 to the hub via the communication interface 12 is further communicated by the hub 40 to each of the further acoustic sensor units 20, 30 and also further to the central control unit 60.

Thus, a network is realized by the acoustic sensor units 10, 20, 30, the network node 40 and the central control unit 60. In order to be able to implement the addressing of the acoustic sensor units 10, 20, 30 and the central control unit 60 in the network, these information transmitted by the control unit 13 via the communication interface 12 are transmitted together with addressing information. As such, the addressing information is, in particular, a network address. Each of the acoustic sensor units 10, 20, 30 and the central control unit 60 is assigned such a network address. The information emitted by the acoustic sensor unit 10 can thus be transmitted in a targeted manner to one of the further acoustic sensor units 20, 30 or to the central control unit 60. Accordingly, the acoustic sensor unit 10 is also assigned addressing information, which means that the acoustic sensor unit 10 has its own network address. The acoustic sensor unit 10 receives the following information via the communication interface 12: the information has addressing information related to the acoustic sensor unit 10. In this case, protocols known from the ethernet protocol for automation applications are basically used. Exemplary protocols are protocols for 100Base-T1 or 1000 Base-T1. Thus providing sufficient bandwidth. The combination of Power-Over-Data-Line communication (also called Power-Over-Data-Line, pod) with this protocol enables the acoustic sensor units 10, 20, 30 to be supplied with a supply voltage by Twisted-Pair cables (Twisted-Pair-Kabel), respectively, and the acoustic sensor units 10, 20, 30 can likewise communicate with the rest of the network via said cables. Via the power line communication, the acoustic sensor unit 10 is provided in particular with a supply having a direct voltage of 12 volts, wherein the supply is in particular a 5 watt supply.

The acoustic sensor unit 10 is adapted to control the measurement cycle performed by the acoustic sensor unit 10 and the further acoustic sensor units 20, 30. After this measurement period, the object information is transmitted via the communication interface 12, wherein the object information is preferably transmitted to the central control unit 60. The two steps of such a measurement cycle are shown in fig. 4 and 5.

The measurement cycle is started by: a start signal is sent by the central control unit 60 to the acoustic sensor unit 10. If the start signal is received by the acoustic sensor unit 10, the transmitting unit 11 is excited by the control electronics 13 to emit an acoustic signal 100. The acoustic signal 100 is here an ultrasound signal. At the same time, a control signal is output by the control electronics 13 via the communication interface 12 in order to control the first and second further acoustic sensor units 20, 30 to provide sensor information that describes the characteristics of the acoustic signal 100 when it is received by the respective further acoustic sensor unit 20, 30. The steps are shown in fig. 4. Here, the following is not necessary: all acoustic sensor units of the network provide sensor information and communicate it to the acoustic sensor unit 10. Since the addressing of the individual acoustic sensor units of the network and thus of the further acoustic sensor units 20, 30 can be realized, it is possible to specifically select by the acoustic sensor unit 10: which of the acoustic sensor units of the network, and thus of the sensor system 200, provides the sensor information.

In this way, for example, the signal propagation times of the acoustic signal 100 are determined by the further acoustic sensor units 20, 30 and are transmitted as sensor information to the acoustic sensor unit 10. Alternatively, the signal propagation time is found based on the transmission timing of the control signal. The signal propagation time is received by the control electronics 30 as sensor information via the communication interface 12. It is noted that only signal propagation times are chosen here as exemplary sensor information. Alternatively or additionally, further sensor information may also be received from further acoustic sensor units 20, 30 via the communication interface 12. Other exemplary sensor information is the signal strength, direction of reception, and signal frequency of the acoustic signal 100 as it is received.

Based on the characteristics of the emitted acoustic signal 100 and on the sensor information, object information is generated, which describes characteristics of the object 110 on which the acoustic signal 100 is reflected. Thus, the characteristic of the transmitted acoustic signal is, for example, the transmission time instant at which the acoustic signal 100 is transmitted. The sensor information is, for example, the signal propagation time of the acoustic signal 100 or also only the reception time of the acoustic signal 100 at the further acoustic sensor units 20, 30. As such, the sensor information preferably includes characteristics of the transmitted acoustic signal 100. The object information is calculated on the basis of the sensor information provided to the control electronics 13 by the further acoustic sensor units 20, 30 and preferably on the basis of these information provided to the control electronics by the transmitting unit 11. As such, the transmitting unit 11 is preferably also adapted to receive echoes of the acoustic signal 100 previously transmitted by the transmitting unit. The acoustic sensor unit 10 is therefore preferably also suitable for carrying out echo-based environment detection independently, wherein an acoustic signal 100 is emitted by the transmitting unit 11 and an echo of the acoustic signal 100 is received, and a property of the object 110 on which the acoustic signal 100 is reflected is inferred, for example, on the basis of the propagation time of the acoustic signal 100. The object information can be further accurately explained in the following way: sensor information received from the further acoustic sensor units 20, 30 via the communication interface 12 is considered. In this way, the position of the object 110 relative to the acoustic sensor unit 10 can be deduced, for example, on the basis of the signal propagation time proceeding from the acoustic sensor unit 10 to the further acoustic sensor units 20, 30 and the signal propagation time to the acoustic sensor unit 10. Thus, for example, triangulation can be performed based on different signal propagation times. Therefore, the object information is preferably the position of the object 110 with respect to the acoustic sensor unit 10.

For this purpose, the control unit 13 advantageously generates object information on the basis of arrangement information describing the arrangement of the further acoustic sensor units 20, 30 relative to the acoustic sensor unit 1. This means that the control electronics 13 preferably knows the arrangement of the further acoustic sensor units 20, 30. Therefore, the pose of the object 110 with respect to the acoustic sensor unit 10 can be calculated based on geometric calculations. The layout information is stored in the control electronics 13 or is likewise received via the communication interface 12. The arrangement information is preferably provided to the control electronics 13 by the central control unit 60.

It is noted that the object information does not necessarily describe the pose of the object 110. Instead, the object information describes the distance of the object from the acoustic sensor unit 10, the surface properties of the object 110, or the relative speed of the object 110 with respect to the acoustic sensor unit 10.

If the object information has been generated, i.e. calculated, by the control electronics 13, the object information is transmitted via the communication interface 12. This step is shown in fig. 5. The object information is preferably transmitted to the central control unit 60. However, the object information may also be provided to other acoustic sensor units of the sensor system 200, in order to enable the other acoustic sensor units to further advantageously calculate additional object information.

It follows that the acoustic sensor unit 10 emits an acoustic signal 100 through the transmission unit 11 in response to the reception of the start signal, outputs a control signal through the communication interface 12, receives sensor information through the communication interface 12, generates object information, and transmits the object information through the communication interface 12. Thus, only a single signal is received by the acoustic sensor unit 10 and in response thereto object information is provided, which already describes the properties of the object and is not limited to sensor information only. The corresponding signal processing takes place by the acoustic sensor unit 10 and is therefore no longer carried out by the central control unit 60.

The acoustic sensor units 10, 20, 30 of the sensor system are structurally identical acoustic sensor units. This means that the measuring period is controlled by the respective sensor unit 10, 20, 30 depending on which of the acoustic sensor units 10, 20, 30 the start signal is sent to. Thus, the acoustic sensor unit 10 is also provided for receiving acoustic signals of the further acoustic sensor units 20, 30, and the control electronics 13 is also provided for receiving control signals of the further acoustic sensor units 20, 30 via the communication interface 12, and in response to the reception of the control signals, on the basis of the received acoustic signals 100, generating sensor information for the further acoustic sensor units 20, 30, which describes characteristics of the received acoustic signals, and transmitting the sensor information via the communication interface 12. The following is thus made possible by the sensor system according to the invention: only the start signal is required and the relevant measurement cycle is implemented and coordinated by one of the acoustic sensor units 10, 20, 30. Here, coordinates defining the arrangement of the individual acoustic sensor units 10, 20, 30 are preferably taken into account.

In a further preferred embodiment of the invention, information is obtained from the other acoustic sensor units 20, 30 in a targeted manner by the acoustic sensor unit 10 in order to be able to carry out object recognition. In this way, for example, additional acoustic sensor units 20, 30 can be specifically controlled in other measuring cycles or can be specifically controlled to provide sensor information. The object information can thus also be generated on the basis of a plurality of measurement cycles. Object recognition controlled by the acoustic sensor unit 10 can also be performed. Therefore, it is preferable that a request (Anfrage) for object recognition be transmitted to the acoustic sensor unit 10 only by the start signal by the central control unit 60, and an object identified based on object typing or object coordinates be provided as the object information by the acoustic sensor unit 10. However, this does not exclude further processing of the object information by the central control unit 60 on the basis of other sensor information, which is provided, for example, by other sensor systems (e.g. environmental cameras). Optionally, such other sensor systems are also coupled to the central control unit 60 via the network node 40.

In general, the acoustic sensor unit 10 emitting the acoustic signal 100 is therefore preferably responsible for object detection. The acoustic sensor unit 10 can recognize, based on the arrangement information, which of the further acoustic sensor units 20, 30 can provide the sensor information required for the scanning of the object 110. Accordingly, these sensor information are requested by the further acoustic sensor unit 20, 30, and echoes received by the further acoustic sensor unit 20, 30 are provided to the acoustic sensor unit 10. The object information is provided as soon as all information of the acoustic sensor unit 10 and the further acoustic sensor units 20, 30 has entered (eingeflossen) the object information to be generated.

In an alternative embodiment, the acoustic sensor units 10, 20, 30 are connected to each other by a bus system. In this case, the network node 40 is no longer required. A particularly simple design of the sensor system can thus be achieved.

In addition to the above disclosure, explicit reference is also made to the disclosure of fig. 1 to 5.