Sensor assembly for a vehicle

Abstract

The invention relates to a sensor assembly (1) of a vehicle, comprising a control device (2), a plurality of sensors (3), a data bus (4) and a supply line (5), wherein each sensor (3) has an individual sensor identifier, the data bus connects each sensor (3) with the control device (2), the supply line connects each sensor (3) with the control device (2) for voltage supply, wherein each sensor (3) has a shunt resistor (31), wherein all shunt resistors (31) are integrated in series into the supply line (5), wherein each sensor (3) is configured to detect a voltage drop at its respective shunt resistor (31), and wherein the control device (2) is configured to manipulate each sensor (3) by means of the individual sensor identifier and to assign each sensor (3) an individual geographical address based on the detected voltage drop along the supply line (5).

Description

TECHNICAL FIELD

[0001] The application relates to a sensor assembly for a vehicle and to a method for addressing sensors of the sensor assembly. BACKGROUND

[0002] Sensor assemblies for assistance systems, for example parking assistance systems, for vehicles are known, which sensor assemblies comprise a plurality of usually identical ultrasonic sensors. Before the assistance system is first put into operation or when individual sensors are replaced, correct addressing of the sensors is necessary in order to be able to assign sensor data of each sensor to the correct physical position relative to the other sensors. For this purpose, usually expensive hardware and / or complex calibration processes are required. SUMMARY

[0003] In contrast thereto, the sensor assembly according to the application having the features of claim 1 is characterized in that the addressing of the sensors can be realized in a particularly simple manner and with simple and cost-advantageous hardware. This is achieved by a sensor assembly comprising a control device, a plurality of sensors, a data bus connecting each sensor with the control device for data transmission and a supply line connecting each sensor with the control device for voltage supply. Preferably, the voltage supply to the sensors is understood here as the integration of an electrical energy source for providing the voltage supply of the sensors into the control device. Preferably, instead, an electrical energy source separate from the control device can also be provided for providing the voltage supply of the sensors, such as a vehicle battery. For example, in the case of such a separate energy source, the control device can supply the sensors with voltage, wherein the control device is in particular configured for interrupting the voltage supply and switching it to the sensors. Preferably, all sensors are connected to the control device here in parallel by means of the data bus. Here, each of the sensors has an individual sensor identifier, for example an individual serial number, which can be read in particular by the control device.

[0004] Each sensor has a shunt resistor. All shunt resistors of the sensors are integrated into the supply line in series, i.e. are connected to one another in series. Each sensor is configured to detect a voltage drop at its respective shunt resistor. Here, the control device is configured to individually, in particular separately, actuate each sensor of the plurality of sensors by means of an individual sensor identifier. Preferably, the control device here actuates all sensors in turn or simultaneously instead. Furthermore, the control device is configured to assign an individual geographical address to each sensor on the basis of the voltage drop along the supply line detected by the sensor. Here, the geographical address is to be understood as an address by means of which the control device can identify the order of the sensors on the data bus. Preferably, the control device is here configured to determine the timing and / or the number of the detected voltage drops over the shunt resistors and to assign a geographical address to the sensors on the basis thereof. Here, the voltage drop is in particular to be understood as an increase or change in voltage over the shunt resistor caused by a predetermined actuation of at least one sensor. In other words, a constant voltage caused, for example, by a static current and / or a voltage offset in the shunt resistor is not to be understood as such a voltage drop.

[0005] In other words, each of the sensors has a shunt resistor by means of which it can be identified when current flows through the respective sensor. Since the shunt resistors are arranged in series, the current flows through all sensors and their shunt resistors arranged on the data bus in advance, i.e. closer to the control device, when a certain sensor is actuated. Thus, a voltage drop can be recorded at each of these shunt resistors arranged between the actuated sensor and the control device. Preferably, a voltage drop can also be recorded at the actuated sensor itself, depending on its configuration, or alternatively no longer be recorded there.

[0006] Thus, the position of the actuated sensor on the data bus can be inferred in a simple manner by the number of voltage drops. Thereby, the different sensors can be distinguished from one another on the basis of the detection of the voltage drop over the shunt resistor. In particular, the order of the sensors can thereby be determined. On the basis of this information, an individual geographical address can be assigned to each of the sensors, so that the sensor data generated by the sensors can be uniquely and unambiguously assigned to a location. The geographical address of the sensors can here be distributed centrally by means of the control device. Alternatively or additionally, each sensor can assign the geographical address to itself or to all sensors.

[0007] Therefore, the sensor device can uniquely and definitively assign sensor data transmitted by a specific sensor via the data bus to a predefined location on the data bus. Preferably, the control device can—for example, in the case where the sensor assembly is part of a parking guidance system—thereby identifying which of the sensors is located in which part of the vehicle's bumper cover, thereby determining, for example, the orientation of an obstacle detected in the vehicle's environment. For example, this allows the control device to manipulate a display screen with lateral resolution to visually display the location of the obstacle.

[0008] It is specifically assumed here that the topology of the data bus is known. In other words, the sensor assembly has multiple sensor receivers, on which sensors are arranged, particularly along the direction of the data bus, wherein the sensor receivers are arranged relative to each other at predefined / pre-known positions.

[0009] Preferably, within the sensor, for example on the circuit board of each sensor, the voltage supply to the sensor components of all sensors is substantially parallel with respect to the voltage supply to the control device. That is, the voltage supply to the sensor components can be branched off, for example, within the sensor from the supply lines circulating via shunt resistors. The sensor assembly here offers the advantage that, when a geographic address is uniquely and explicitly assigned geographically to a sensor, the voltage supply to the sensor components of all sensors is substantially parallel with respect to the supply voltage. With this design, all sensor components can obtain an optimal voltage supply. In particular, the internal resistance of the sensor or its components thus has little or no effect on the voltage supply to the sensor components. This enables the linking of virtually any number of sensors on the data bus.

[0010] Preferably, the supply line and data bus can be configured as separate cables. Alternatively, the supply line and data bus may be combined in a common cable, which is preferably routed to the sensor at a single pin.

[0011] The data bus preferably has a single data line, to which each of the sensors is connected. Alternatively, the data bus can also have two or more data lines, with each sensor connected to each data line.

[0012] The sensors are preferably constructed in a consistent manner, i.e., identically constructed, wherein, however, each sensor has an individual sensor identifier, such as an individual serial number.

[0013] Thus, by virtue of the connection of the sensors to the control device via the data bus, each sensor can be addressed individually to the control device with particularly low hardware outlay, in particular without the need for individual wiring of each sensor to the control device via a separate line. A further advantage resulting therefrom is that it is possible to replace sensors of identical construction simply, wherein the replaced sensor can be addressed automatically and in a simple manner.

[0014] The content of the dependent claims is a preferred extension of the application.

[0015] Preferably, the sensors generate a current signal on the supply line after being manipulated by the control device, said current signal having a defined frequency signature. That is to say, by virtue of the manipulation of the sensors by means of the control device, each sensor generates a current signal in the supply line having a defined, preferably individual, frequency signature, so that the sensors can be distinguished from one another in particular.

[0016] Preferably, the voltage taps are implemented on the supply line before or after the respective shunt resistor for the voltage supply to the sensor components of each sensor. The voltage tap before the shunt resistor is implemented here such that the self-supply of the sensor components does not influence the voltage drop on the shunt resistor, so that the voltage drop on the shunt resistor can be detected or estimated in a particularly simple manner. Alternatively, the supply of the sensor components can also be branched off after the shunt resistor.

[0017] Preferably, the shunt resistor is a metal film resistor or a copper track. Preferably, the copper track can be part of a sensor printed circuit board of the sensor. Thereby, the shunt resistor can be provided in a particularly simple and cost-advantageous manner. Alternatively, the shunt resistor can also be configured as at least one bond wire or comprise a bond wire. Here, in this configuration there are in particular the following two possibilities to realize the shunt resistor by means of a corresponding bond of the ASIC of the respective sensor component. A first option is that the supply line is bonded by means of a bond wire from a contact point (so-called "pin") on the lead frame of the ASIC to a pad in the silicon, from which the ASIC supply can extend accordingly in the case of an ultrasonic sensor. Furthermore, a low-ohmic connection is established from this pad to an adjacent pad, which can also be configured as a bond wire, wherein from this adjacent pad the lead frame is again bonded by means of a corresponding bond wire. The sum of the resistance values of the bond wires and possibly the resistance value of the connection between the pads in the silicon represents the actual shunt resistor. A second option is that the supply line is bonded by means of a bond wire from the lead frame to a pad in the silicon. Furthermore, a bond is made from the contact point ("pin") 1 of the lead frame to the contact point of the lead frame for the adjacent pin, wherein this bond connection represents the shunt resistor in this second option. Depending on the required resistance value and current-carrying capacity, one embodiment of the shunt resistor can also contain a double bond or a triple bond. Furthermore, the material and thickness of the respective bond wire can be distributed as required.

[0018] Here, the advantage of the respective embodiment of the shunt resistor by means of at least one bond wire is that the costs of such a shunt resistor are significantly lower than those of a conventional shunt resistor. The reason for using a shunt resistor of the respective configuration in general is that the requirements of up to 50% resistance tolerance and a maximum current-carrying capacity of less than 2 A, which are particularly relevant for ultrasonic applications, can continue to be adhered to by means of such a bond wire shunt resistor.

[0019] It is particularly preferred that the shunt resistor has a resistance of at most 0.1 Ω, in particular at most 0.01 Ω and in particular at least 0.001 Ω. Preferably, a low-ohmic resistor is thus involved. Thereby, it is ensured that as little electrical power as possible is consumed by the shunt resistor, i.e. in order to determine the position of the sensor on the data bus.

[0020] Preferably, each sensor has a differential amplifier by means of which the voltage drop over the respective shunt resistor is determined. Preferably, the differential amplifier is designed to amplify the voltage drop over the shunt resistor, so that a particularly precise and reliable detection of the voltage drop can be achieved.

[0021] It is particularly preferred that each sensor comprises a filter which is configured to filter the output signal generated by the respective differential amplifier. The filter is in particular a bandpass filter or an optimal filter. Preferably, the filter can be configured to filter the output signal of the differential amplifier by means of a direct voltage coupling and / or by means of an alternating voltage coupling. The detection of all components of the input signal of the differential amplifier is considered to be a direct voltage coupling. This results in a particularly simple and cost-advantageous configuration of the sensor assembly. The unambiguous detection of the current in the respective shunt resistor can preferably be detected by means of a comparison of the respective voltage drop with a predefined voltage threshold. The detection of only one alternating voltage component of the input signal of the differential amplifier is considered to be an alternating voltage coupling. Thereby, the particularly robust determination of the voltage drop can be realized in a form which is less susceptible to interference, so that a manipulation of a certain sensor can be unambiguously determined. In particular, if a current pulse is generated when a certain sensor with a certain frequency signature is manipulated, this frequency signature in the detected voltage drop can be determined by means of a filter with alternating voltage coupling. Thereby, it can be precisely recognized whether there is a targeted manipulation of the sensor, since, for example, static current consumption or voltage offsets in the supply line are filtered out.

[0022] Preferably, the ground line and / or the data bus is guided through each sensor, in particular by means of the input pin and the output pin of each sensor, respectively. The ground line and / or the data bus is in particular thereby divided into a plurality of individual partial sections. Preferably, the data bus is guided through the sensors in such a way that the data exchange continues to take place as in the case of a parallel connection of the sensors. That is to say, within the sensors, for example on the circuit board of each sensor, the data exchange takes place in parallel with respect to the control device. Thereby, all interfaces of the sensors can be connected by means of the pins, so that the sensors do not have to be connected to the ground line and / or the data bus by means of additional connection lines and splices. Depending on the design of the sensor assembly, a cost advantage can thereby be achieved.

[0023] It is particularly preferred that the control device has a non-volatile memory. Alternatively or additionally, each sensor has a non-volatile memory. By means of such a non-volatile memory, the assigned geographical address can be stored, so that the assignment program only has to be executed once, since the geographical address can then be read from the non-volatile memory. Alternatively, the control device and / or all sensors can be designed without memory, i.e. without a memory. Thereby, a particularly cost-advantageous sensor assembly can be provided. In this case, an addressing has to be carried out before each operation of the sensor assembly. Due to the special design of the sensor assembly, an especially fast and resource-saving addressing can still be carried out here.

[0024] Preferably, the sensors are ultrasonic sensors. The sensor assembly is thus in particular an ultrasonic system, which can be used for distance detection. For example, the sensor assembly can be used for distance detection for a parking guidance system or other driver assistance systems. Preferably, the ultrasonic sensors are fastened in fixed positions on a panel part of the vehicle. The ultrasonic sensors are here in particular fastened in the bumpers of the vehicle, wherein preferably at least 2 and at most 12 ultrasonic sensors are provided on each bumper.

[0025] Furthermore, the application leads to a method for addressing sensors of a sensor assembly. Preferably, the sensor assembly is the above-described sensor assembly.

[0026] The sensor assembly has a control device, a plurality of sensors, a data bus and a supply line, wherein each sensor has an individual sensor identifier, the data bus connects each sensor with the control device and the supply line connects each sensor with the control device for voltage supply. Each sensor has a shunt resistor. All shunt resistors of the plurality of sensors are integrated in series into the supply line, that is to say, arranged in the supply line in series. Here, the method comprises the following steps for each sensor:

[0027] - recognizing the sensor identifier of the sensor,

[0028] - manipulating the sensor on the basis of the sensor identifier,

[0029] - determining the voltage drop at the shunt resistor of all sensors, and

[0030] - assigning the manipulated sensor an individual geographical address on the basis of the determined position.

[0031] Here, the position of the manipulated sensor is determined on the basis of the detected voltage drop along the supply line. Preferably, the position of the manipulated sensor is determined on the basis of the timing and / or the amount of the detected voltage drop along the supply line. By detecting the voltage drop over the shunt resistor, it can be determined in a very simple manner how the sensors are arranged relative to one another, that is to say, in which order these sensors are. Since the shunt resistors are arranged in series, the current flows through all shunt resistors arranged on the data bus in advance, that is to say, arranged closer to the control device, when a certain sensor is manipulated. A voltage drop can thus be recorded at each of these shunt resistors. The position of the manipulated sensor on the data bus can thus be inferred in a simple manner by the amount of the voltage drop. The method thus allows a particularly simple possibility for addressing sensors, which can be carried out automatically in the case of a structure of the sensor assembly that is particularly advantageous in terms of costs and optimized in terms of low electrical losses.

[0032] Preferably, the method for addressing the sensors is performed exactly once, in particular in the case of a first commissioning of the sensor assembly. Alternatively, the method can be performed each time the sensor assembly is operated.

[0033] Preferably, all sensors are manipulated in turn, and wherein, after manipulation of all sensors, the order of the sensors on the data bus is determined on the basis of the decreasing number of voltage drops detected at each sensor. On the basis of the order of the sensors on the data bus, individual geometrical addresses can subsequently be assigned to all sensors. Preferably, each sensor is here manipulated individually exactly once. Alternatively, all sensors can also be manipulated several times, wherein, in particular, all sensors are manipulated at the same frequency. In other words, the sensors are sorted from the control device starting according to the decreasing number of voltage drops detected at each sensor. That is to say, the sensor having the most voltage drop determined at its shunt resistor is located in the first position on the data bus from the direction of the control device. Correspondingly, the sensor having the least voltage drop recorded is at the end of the data bus. Thus, the order of the sensors on the data bus can be determined particularly simply and with minimal computational outlay, according to which the geographical addresses can also be assigned uniquely unambiguously.

[0034] Preferably, each sensor is manipulated individually, wherein the total number of voltage drops at all sensors is determined during each manipulation of an individual sensor. The position of each individually manipulated sensor is here determined relative to the other sensors on the basis of the total number of voltage drops detected at all sensors. That is to say, according to the total number of voltage drops detected when manipulating an individual sensor, the number of sensors on the data bus between the manipulated sensor and the control device can be determined. For example, if the voltage supply of the sensor component of the manipulated sensor is branched before its shunt resistor, the number of voltage drops detected corresponds to the number of sensors arranged in front. Thus, the position of each sensor on the data bus can also be determined in a particularly simple manner and with little computational outlay. Here, the assignment of the geographical addresses can take place respectively immediately after the position of the manipulated sensor has been determined, or alternatively after all positions of the sensors have been determined.

[0035] Alternatively, preferably each sensor is manipulated simultaneously, in particular synchronously. After simultaneous manipulation of each sensor, the size of the voltage drop determined at each sensor is determined The respective measured total voltage drop at the respective sensor in the chain is thus determined how high it is. The position of the manipulated sensor relative to the other sensors is determined on the basis of the magnitude of the voltage drop determined at each sensor as follows. The sensor that is closest in the direction towards the data bus determines the greatest total voltage drop accordingly, since this sensor detects the voltage drop of all sensors that follow it in the sequence. In contrast, the sensor that is farthest in the direction towards the data bus determines the smallest total voltage drop. The sequence of the sensors on the data bus is determined accordingly on the basis of the decreasing magnitude of the voltage drop at the respective sensor. The advantage of the synchronous method is a faster completion of the operation compared to the sequential method and a duration that is independent of the number of sensors on the bus. In this synchronous method, each sensor is preferably configured to measure the magnitude of the voltage drop with sufficient accuracy and subsequently to transmit it to the control device.

[0036] Preferably, the voltage drop over the shunt resistor is amplified by means of a differential amplifier of each sensor, respectively. The output signal generated by the differential amplifier is filtered by means of a filter of each sensor, respectively. The magnitude of the voltage drop over the shunt resistor is determined on the basis of the filtered output signal. Preferably, the filter filters the output signal of the differential amplifier by means of a bandpass filter or an optimal filter. On the basis of the determined magnitude of the voltage signal, it is possible to verify the detected manipulation of the respective sensor, preferably. Preferably, the selection of the filter parameters by means of a frequency signature corresponding to the manipulation signal provided by the control device by means of which the sensor is manipulated enables a unique determination of whether there is an actual, targeted manipulation or whether an interference signal has been detected, etc. Thereby, a particularly high robustness in the method for addressing the sensors can be achieved.

[0037] It is particularly preferred that each sensor is assigned a logical address on the basis of the sensor identifier prior to the manipulation. The manipulation of the sensor is effected here by means of the logical address. By means of the assignment of the logical address to the sensor, the control device can particularly easily distinguish the sensors from one another and directly manipulate the sensors individually.

[0038] Preferably, each assigned geographical address is stored in a non-volatile memory of the respective sensor and / or in a non-volatile memory of the control device. For example. Thereby, only one addressing of the sensors is necessary. Upon a restart of the sensor assembly, the geographical addresses can be simply read out of the one or more non-volatile memories by means of the control device, so that a readdressing of the sensors is not necessary.

[0039] Preferably, on the basis of the unknown and / or changed individual sensor identifier, it is possible to recognize when one of the sensors has been replaced, for example in the case of a repair. In response to such a recognition, a reassignment of the geographical addresses can be initiated, preferably. Attached Figure Description

[0040] The present invention will now be described with reference to the accompanying drawings and embodiments. In the drawings, components with the same function are indicated by the same reference numerals.

[0041] This is shown here:

[0042] Figure 1 A simplified schematic view of a sensor assembly according to a first embodiment of the present invention.

[0043] Figure 2 Figure 1 A simplified schematic view of the sensor assembly in its mounted state on a vehicle panel.

[0044] Figure 3 A simplified schematic view of a sensor assembly according to a second embodiment of the present invention. Detailed Implementation

[0045] Figure 1 A simplified schematic view of a sensor assembly 1 for a vehicle according to a first embodiment of the present invention is shown. The sensor assembly 1 includes a control device 2 and a plurality of sensors 3. For example, the sensor assembly 1 may include three sensors, as shown in the figures. Alternatively, any number of sensors 3 is possible, preferably two, four, or six sensors 3. The sensors 3 are identical in design, i.e., constructed identically, but have different individual serial numbers. The sensors 3 are ultrasonic sensors, which identify objects in the vicinity of the vehicle by transmitting and receiving ultrasonic signals.

[0046] As in Figure 2 As schematically simplified, sensor assembly 1 can be mounted in a (not shown) vehicle panel 100. Sensors 3 are arranged in predefined positions on panel 100. In order to spatially distribute the sensor data generated by the sensors 3, i.e., to distinguish, for example, whether determined sensor data has been generated by the sensor 3 on the left or right side along the direction of travel A, each sensor 3 needs to be geographically addressed before initiating environmental detection using sensor assembly 1.

[0047] The design structure of sensor component 1 and the addressing of sensor 3 are described below.

[0048] The sensor assembly 1 includes a supply line 5, a grounding line 50, and a data bus 4, wherein the data bus has two parallel data lines 41 and 42.

[0049] The ground line 50 and the two data lines 41, 42 are each configured as a single piece line which connects the sensors 3 to the control device 2. For the connection to the sensors 3, a connection element 45, 57 in the form of a short line piece is provided for each line. Furthermore, each sensor 3 has an output pin 43, 56 for connection to these connection elements 45, 57.

[0050] The supply line 5 is divided into a plurality of supply line pieces 59 which each connect the control device 2 to the first sensor 3 to one another and the sensors 3 arranged in series to one another. The supply line pieces 59 are here connected to each sensor 3 by means of an input pin 52 or an output pin 53.

[0051] By means of the individual sensor identifiers, the control device 2 is able to distinguish the sensors 3 from one another individually. Here, the control device 2 is able to assign each sensor 3 a logical address on the basis of its individual sensor identifier in order to be able to individually control and distinguish the sensors 3.

[0052] Each sensor 3 has a shunt resistor 31. The shunt resistors 31 of all sensors 3 are integrated in series into the supply line 5. Thus, the wiring with regard to the shunt resistors 31 can be regarded as a "Daisy Chain".

[0053] The shunt resistors 31 are configured as low-ohmic, in particular with a resistance of a maximum of 0.1 Ω, such that only a small amount of electrical power falls across the shunt resistors 31.

[0054] Furthermore, each sensor 3 has a sensor component 35, which is configured, for example, as a transducer for generating and receiving ultrasound signals. The voltage supply of the sensor component 35 is here carried out by means of a voltage tap before the respective shunt resistor 31 of the sensor 3. Since the shunt resistor 31 is low-ohmic, the sensor component 35 can essentially be regarded as being connected in parallel with regard to the voltage supply by means of the control device 2.

[0055] Each sensor 3 is here provided for detecting a voltage drop at its shunt resistor 31. Such a voltage drop can be detected when a current flows through the respective shunt resistor 31. This is the case if one of the subsequent sensors 3 is controlled in the sequence of the sensors 3 along the data bus 4.

[0056] The voltage drop over the shunt resistor 31 is detected and analyzed here by means of a differential amplifier and filter. The differential amplifier and filter are part of the sensor component 35 here and are not shown individually in the drawing. The differential amplifier is designed to amplify the voltage drop over the shunt resistor 31. The filter is also designed to filter the output signal of the differential amplifier by means of a bandpass filter or optimal filter. As a result, the frequency in the voltage signal falling over the shunt resistor 31 can be determined in order to achieve a reliable identification of the current by means of a corresponding sensor 3 with high immunity to interference.

[0057] The geographical addressing of the sensors 3 here can be based on the detection of the voltage drop along the supply line 5, as described below.

[0058] Initially, all sensors 3 are activated by the control device 2. Each sensor 3 is activated individually, i.e. in succession. The activation is carried out here in such a way that each sensor 3 emits an ultrasonic signal. To this end, each sensor is activated with a current pulse having a predetermined frequency signature. At the same time, all sensors 3 detect during the activation of any sensor 3 whether there is a voltage drop at their shunt resistor 31. By analyzing the voltage drop over the shunt resistor 31, which is optimized by means of a differential amplifier and filter, it can be uniquely determined here whether the respective sensor 3 has been deliberately activated by the control device 2 or, for example, whether there is an interfering signal or a constant voltage offset. After each sensor 3 has been activated exactly once, the number of detected voltage drops of each sensor 3 is determined. Subsequently, the order of the sensors 3 on the data bus is determined on the basis of the decreasing number of detected voltage drops of each sensor 3. That is to say, the sensor 3 with the most voltage drops is in the first position on the data bus 4 from the control device 2.

[0059] Subsequently, the respective geographical address is assigned to the sensors 3 by the control device 2 in accordance with the determined order.

[0060] The sensor assembly 1 and the method for addressing are characterized here by a particularly cost-effective design and simple executability. A particular advantage is that, while all sensors 3 are supplied with voltage almost in parallel, there is still a series connection of the sensors 3 by means of the shunt resistor 31, which allows the relative position of all sensors 3 relative to one another to be determined by counting the voltage drop along the data bus 4.

[0061] Since the voltage supply takes place almost in parallel, all sensors 3 can be supplied with the same operating voltage. Thus, the sensor assembly 1 can be expanded by any number of sensors 3, wherein all sensors 3 can always be supplied with the same voltage in the case of a simple and cost-effective device design of the sensor assembly 1.

[0062] The following describes alternative execution schemes for the addressing.

[0063] Instead of the above-described sequencing, it is also possible to individually determine the position of each sensor 3 on the data bus 4 in a simple manner. For this purpose, each sensor 3 is individually manipulated exactly once.

[0064] After the manipulation of the individual sensor 3, the total amount of the voltage drop over all sensors 3 of the sensor assembly 1 is determined. Subsequently, the position of the manipulated individual sensor 3 relative to the other sensors 3 is determined on the basis of the total amount of the voltage drop in the sensor assembly 1. Here, the control device 2 can identify on the basis of the total amount of the voltage drop how many sensors 3 are arranged on the data bus 4 before the just manipulated sensor 3 and thus identify the position of the manipulated sensor 3.

[0065] Since the current flows through all sensors 3 arranged before in the data bus 4 when a certain sensor 3 is manipulated, a voltage drop is detected on each of these sensors 3. For example, if the middle sensor 3 is manipulated in the sensor assembly 1 shown in Figure 1 , there is a current in the shunt resistor 31 only at the left, i.e. the first sensor 3 on the data bus 4. On the basis of this, the control device 2 can identify that only one sensor 3 is arranged before the manipulated sensor 3 and that this sensor is thus located in the second position on the data bus 4.

[0066] Subsequently, the assigned geographical address can be stored in the non-volatile memory of the control device 2 and / or in the non-volatile memory of the manipulated sensor 3. Alternatively, it is also possible to provide a sensor 3 without memory and a control device 2 without memory, wherein the addressing is performed each time the sensor assembly 1 is started.

[0067] In another alternative, all sensors 3 generate a current pulse simultaneously, i.e. synchronously. After the manipulation of each sensor 3 at the same time, the size of the voltage drop determined on each sensor is determined. Thus, it is determined how high the total voltage drop measured at the respective sensor 3 in the chain is. The position of the manipulated sensor 3 relative to the other sensors 3 is determined on the basis of the size of the voltage drop determined at each sensor 3 as follows. The left sensor 3 closest in the direction towards the data bus 4 determines the largest total voltage drop, since this sensor detects the voltage drop of all sensors 3 located after it in the sequence. In contrast, the right sensor 3 farthest in the direction towards the data bus 4 determines the smallest total voltage drop. The order of the sensors 3 on the data bus 4 is determined accordingly on the basis of the decreasing size of the voltage drop on the respective sensor 3.

[0068] Figure 3A simplified schematic view of a sensor assembly 1 according to a second embodiment of the present invention is shown. The second embodiment substantially corresponds to... Figure 1 In the first embodiment, alternative wiring for sensor 3 is provided. Figure 3 In the second embodiment, the supply line 5, the ground line 50, and the data bus 4 are respectively routed through each sensor 3. Here, each sensor 3 has input pins 52, 43, 56 and output pins 53, 44, 57 for each line 5, 4, 50. Here, within each sensor 3, for example on the circuit board of each sensor 3, voltage taps are made as previously described, such that the sensor components 35 of all sensors 3 to be supplied with voltage are connected substantially in parallel with the control device 2. Similarly, data exchange can be further performed in parallel with respect to the control device 2. This design saves on connection points on the lines, i.e., so-called "joints".

Claims

1. A sensor assembly for a vehicle, the sensor assembly comprising: - Control device (2) - Multiple sensors (3), wherein each sensor (3) has an individual sensor identifier, - A data bus (4) that connects each sensor (3) to the control device (2), and - Supply line (5), which connects each sensor (3) to the control device (2) for voltage supply. Each sensor (3) has a shunt resistor (31). All shunt resistors (31) are integrated in series into the supply line (5). Each sensor (3) is configured to detect the voltage drop at its corresponding shunt resistor (31), and The control device (2) is configured to: - Manipulate each sensor (3) using the sensor identifier of the individual, and - Assign an individual geographic address to each sensor (3) based on the detected voltage drop along the supply line (5).

2. The sensor assembly of claim 1, wherein, After the sensor (3) is manipulated, the sensor generates a current signal on the supply line (5), the current signal having a defined frequency signature.

3. The sensor assembly of claim 1 or 2, wherein, In order to supply voltage to the sensor component (35) of the sensor (3), the voltage tap of each sensor (3) is constructed on the supply line (5) before or after the corresponding shunt resistor (31).

4. The sensor assembly of claim 1 or 2, wherein, The shunt resistor (31) is a metal film resistor or a copper printed wire or includes at least one bonding wire.

5. The sensor assembly of claim 1 or 2, wherein, The shunt resistor (31) has a maximum resistance of 0.1Ω.

6. The sensor assembly of claim 1 or 2, wherein, The shunt resistor (31) has a maximum resistance of 0.01Ω.

7. The sensor assembly of claim 1 or 2, wherein, The shunt resistor (31) has a resistance of at least 0.001Ω.

8. The sensor assembly of claim 1 or 2, wherein, Each sensor (3) has a differential amplifier, which is used to determine the voltage drop across the corresponding shunt resistor (31).

9. The sensor assembly of claim 8, wherein, Each sensor (3) includes a filter, wherein the filter is configured to filter the output signal generated by the differential amplifier.

10. The sensor assembly of claim 9, wherein, The filter is a bandpass filter or an optimal filter.

11. The sensor assembly according to claim 1 or 2, wherein, The grounding line (50) of the sensor assembly and / or the data bus (4) are guided through each sensor (3).

12. The sensor assembly of claim 11, wherein, The grounding line (50) and / or the data bus (4) are guided through each sensor (3) via the input pin (43, 56) and output pin (44, 57) of each sensor (3), respectively.

13. The sensor assembly according to claim 1 or 2, wherein, The control device (2) and / or each sensor (3) has a non-volatile memory, or wherein the control device (2) and / or each sensor (3) is configured to be memoryless.

14. The sensor assembly according to claim 1 or 2, wherein, The sensor (3) is an ultrasonic sensor.

15. A method for addressing a sensor (3) of a sensor assembly (1), wherein, The sensor assembly (1) includes a control device (2), multiple sensors (3), a data bus, and a supply line (5), wherein each sensor (3) has an individual sensor identifier, the data bus (4) connects each sensor (3) to the control device (2), the supply line connects each sensor (3) to the control device (2) for voltage supply, and each sensor (3) has a shunt resistor (31), wherein all shunt resistors (31) are integrated in series into the supply line (5), and The method includes the following steps for each sensor (3): - Identify the sensor identifier of the sensor (3), - Manipulate the sensor based on the sensor identifier (3). - Calculate the voltage drop at the shunt resistor (31) of all sensors (3). - Determine the position of the manipulated sensor (3) relative to the other sensors (3), and - Assign an individual geographic address to the sensor (3) based on the obtained location. The position of the manipulated sensor (3) is determined based on the detected voltage drop along the supply line (5).

16. The method according to claim 15, wherein, All sensors (3) are manipulated sequentially, wherein, after all sensors (3) are manipulated, the order of the sensors (3) on the data bus (4) is determined based on the decreasing number of voltage drops detected by each sensor (3).

17. The method according to claim 15, wherein, Each sensor (3) is manipulated individually, wherein after each manipulation of a single sensor (3), the total amount of voltage drop at all sensors (3) is determined, wherein the position of the manipulated sensor (3) relative to the other sensors (3) is determined based on the total amount of voltage drop.

18. The method according to claim 15, wherein, Each sensor (3) is manipulated simultaneously, wherein, after each sensor (3) is manipulated simultaneously, the magnitude of the voltage drop at each sensor is determined, wherein the position of the manipulated sensor (3) relative to the other sensors (3) is determined based on the magnitude of the voltage drop at each sensor.

19. The method according to claim 18, wherein, Each sensor is manipulated synchronously (3).

20. The method according to any one of claims 15 to 19, wherein, The voltage drop across the shunt resistor (31) is amplified by a differential amplifier, wherein the output signal generated by the differential amplifier is filtered by a filter matched to the frequency signature, wherein the magnitude of the voltage drop across the shunt resistor (31) is determined based on the output signal of the filter.

21. The method according to any one of claims 15 to 19, wherein, Each sensor (3) is assigned a logical address based on a sensor identifier before manipulation, wherein the sensor (3) is manipulated by means of the logical address.

22. The method according to any one of claims 15 to 19, wherein, Each geographic address is stored in the non-volatile memory of each sensor (3) and / or the non-volatile memory of the control device (2).

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