Communication control device, communication control procedure and communication control program

Abstract

A communication control device (50) configured to control communication between a central unit and a sensor unit in a sensor system (1) comprising the central unit (2) as a master device and the sensor unit (3) as a slave device, comprises: a sensitivity acquisition unit (51) that ascertains whether the set sensitivity status during the detection operation of the sensor unit is a predetermined high sensitivity status or a low sensitivity status lower than the high sensitivity status, and a communication control unit (52) that communicates a special communication signal, which is a noise source in the detection operation, in the low sensitivity status and not in the high sensitivity status.

Description

Reference to related applications

[0001] This application claims priority to Japanese Patent Application No. 2022-079069, filed on May 12, 2022. The contents of this application are incorporated herein by reference in their entirety. Technical area

[0002] The present disclosure provides a communication control apparatus, a communication control method, and a communication control program for controlling communication between a central unit and a sensor unit in a sensor system having a central unit as a master device and a sensor unit as a slave device. State of the art

[0003] Patent Document 1 discloses a method for operating a sensor device in a vehicle based on the DSI protocol. DSI stands for Distributed System Interface. A sensor device includes a central unit, which is a master device, and a plurality of sensor units, each of which is a slave device controlled by the master device. The central unit and each of the plurality of sensor units are connected by a bus cable. Communication between the central unit and each of the sensor units is performed via the bus cable. Prior art referencesPatent document

[0004] Patent Document 1: JP6894043B Summary of the invention

[0005] Noise may occur during communication between the central unit and each sensor unit. This noise may cause false detection in the sensor units. On the other hand, if communication between the central unit and the sensor units is not performed at all during detection operations in the sensor units, the detection performance will be limited due to the longer detection operation cycle. The present disclosure has been made in view of the above-mentioned problems. For example, the present disclosure provides a technology that enables communication, which becomes a source of noise, to be performed during detection operations in a sensor unit, and enables effective prevention of false detections in the sensor unit.

[0006] The communication control device is configured to control communication between a central unit and a sensor unit in a sensor system having the central unit as a master device and the sensor unit as a slave device.According to one aspect of the present disclosure, the communication control device includes: a sensitivity acquiring unit that acquires a sensitivity status of the sensor unit during a detection operation in the sensor unit, wherein the sensitivity status is defined as either a high sensitivity status or a low sensitivity status lower than the high sensitivity status; and a communication control unit that communicates special communication signals when the sensitivity acquiring unit acquires the low sensitivity status, wherein the special communication signals are communication signals that are noise sources in the detection operation.

[0007] According to another aspect of the present disclosure, the communication control method is for controlling communication between a central unit and a sensor unit in a sensor system, the sensor system having the central unit as a master device and the sensor unit as a slave device. The communication control method includes: acquiring a sensitivity status of the sensor unit during a detection operation in the sensor unit, wherein the sensitivity status is defined as either a high sensitivity status or a low sensitivity status lower than the high sensitivity status; and communicating special communication signals when the low sensitivity status is acquired, the special communication signals being communication signals that are noise sources in the detection operation.

[0008] According to yet another aspect of the present disclosure, the communication control program is to be executed by a communication control device that controls communication between a central unit and a sensor unit in a sensor system, the sensor system having the central unit as a master device and the sensor unit as a slave device.The communication control program causes the communication control device to perform the following: acquiring a sensitivity status of the sensor unit during a detection operation in the sensor unit, wherein the sensitivity status is defined as either a high sensitivity status or a low sensitivity status lower than the high sensitivity status, and communicating special communication signals when the low sensitivity status is acquired, wherein the special communication signals are communication signals that are noise sources in the detection operation.

[0009] In the various parts of these application documents, each element may be marked with a reference code or reference symbol enclosed in parentheses. However, such reference codes merely indicate an example of the correspondence between the element and the specific means described in the embodiments described later. Therefore, the present disclosure is not limited in any way by the description of the above reference codes. Short description of the characters Fig. 1 is a schematic diagram of a vehicle equipped with a sensor system including the communication control device of the embodiment. Fig. 2 is a block diagram showing the schematic functional configuration of the Fig. 1 shows the sensor system. Fig. 3 is a block diagram showing the schematic functional configuration of the communication control device in the Fig. 2 shows the sensor system. Fig. 4 is a timing diagram showing an example of signal communication in the Fig. 2 shows the sensor system. Fig. 5 is a flowchart showing a specific example of an operation in the Fig. 2 shows the sensor system. Description of the embodiments

[0010] The following is a description of one embodiment of the present disclosure based on the drawings. The descriptions in each drawing and the corresponding descriptions of device configurations and their functions or operations described below are simplified for the purpose of briefly explaining the content of this disclosure and do not limit the content of this disclosure in any way. Therefore, it should be understood that the exemplary configurations shown in the figures do not necessarily correspond to the specific configurations that are manufactured and sold.In other words, it goes without saying that the present disclosure should not be construed as limited by the descriptions in each drawing or the descriptions of the device configuration and its functions or operations described below in response thereto, unless the applicant explicitly limits them through the course of filing this application or otherwise. Therefore, various variations may be applied to the embodiments described below. However, if variations are inserted in the middle of a series of explanations of the embodiments, understanding of the embodiments may be hindered. For this reason, the variant examples will be described together after the explanation of the embodiment. Overall configuration of the sensor system

[0011] With reference to Fig. 1, the sensor system 1 of this embodiment is an in-vehicle system that performs various functions when installed in a vehicle C, which is a mobile object. The vehicle C is a so-called four-wheeled vehicle that runs on the ground, that is, on the road. The vehicle C has a box-like body C1 that is rectangular in a plan view. The shape of each part of the vehicle C in a plan view refers to the shape of the vehicle C when the vehicle C is stably placed on a horizontal surface for running and the part is viewed with a line of sight in the same direction as the direction of gravity. The vehicle C in which the sensor system 1 is mounted is hereinafter referred to as "own vehicle."

[0012] Hereinafter, the virtual straight line passing through the center of the vehicle in the vehicle width direction and parallel to the overall longitudinal direction of the vehicle in a plan view is referred to as the vehicle width center line LC. The vehicle center line LC is also referred to as the vehicle center line. The vehicle longitudinal direction is perpendicular to the vehicle width direction and perpendicular to the vehicle height direction and is also referred to as the vehicle longitudinal direction. The vehicle height direction defines the height of the vehicle and is parallel to the direction of gravity when the vehicle is stably placed on a horizontal surface for driving. In addition, "front", "rear", "left", "right", and "top" are defined as indicated by arrows in Fig. 1. In other words, the overall vehicle longitudinal direction is synonymous with the front-to-rear direction. The vehicle width direction is synonymous with the left-to-right direction.

[0013] The sensor system 1 has a central unit 2 as a master device and a sensor unit 3 as a slave device. A plurality of sensor units 3 can be provided for one sensor system 1. In this embodiment, the sensor system 1 is a communication system conforming to the DSI3 standard. The central unit 2 and the sensor unit 3 send and receive information or signals to and from each other via a communication line 4. The central unit 2 and a plurality of sensor units 3 are connected in any connection configuration, such as a bus, a daisy chain, a star, etc. The sensor system 1 can switch between a command-response mode and a periodic data collection mode. CRM mode stands for "Command and Response Mode," and PDCM mode stands for "Periodic Data Collection Mode."The PDCM mode is an example of a second communication mode that provides one-way communication from the sensor unit 3 to the central unit 2. When a trigger signal is received, the system switches from the first communication mode to the second communication mode.

[0014] In this embodiment, the central unit 2 is an object detection ECU that detects an object B present around the host vehicle using the sensor unit 3, which is an object detection sensor. ECU stands for Electronic Control Unit. The sensor unit 3 is mounted on the host vehicle and receives a wave reflected from the object B of the probe wave transmitted to the outside of the host vehicle. The sensor unit 3 is a so-called distance measuring sensor and acquires distance information. The distance information may be the propagation time between the transmission of the probe wave and the reception of the reflected wave, or the measured distance calculated based on the propagation time. The distance is an estimated distance between the sensor unit 3 and the object B.

[0015] The sensor unit 3 may be, for example, an ultrasonic sensor. The sensor unit 3 detects the presence or absence of object B and the distance to object B by receiving the probe wave reflected from object B, which is an ultrasonic wave transmitted to the outside. In this embodiment, the sensor unit 3 has an integrated transmitter / receiver configuration. In other words, the sensor unit 3 functions as a transmitter that transmits a probe wave to the outside of the vehicle and a receiver that receives a received wave including the probe wave reflected from object B.

[0016] A first front sensor 3A, a second front sensor 3B, a third front sensor 3C, and a fourth front sensor 3D are mounted on the front bumper C2 at the front portion of the vehicle body C1 of the host vehicle. Similarly, a first rear sensor 3E, a second rear sensor 3F, a third rear sensor 3G, and a fourth rear sensor 3H are mounted on the rear bumper C3 at the rear of the vehicle body C1 of the host vehicle. Each of these configurations corresponds to the sensor unit 3.

[0017] The first front sensor 3A is mounted near the left end in the front bumper C2 and transmits a transmission wave to the left front of the vehicle. The second front sensor 3B is mounted between the first front sensor 3A and the vehicle width center line LC in the vehicle width direction and transmits a transmission wave to the front of the vehicle. The third front sensor 3C is mounted symmetrically with the second front sensor 3B above the vehicle width center line LC. The third front sensor 3C is mounted between the vehicle width center line LC and the fourth front sensor 3D with respect to the vehicle width direction. The fourth front sensor 3D, which transmits a transmission wave briefly to the front of the vehicle, is mounted symmetrically with the first front sensor 3A above the vehicle width center line LC.The fourth front sensor 3D is mounted near the right end in the front bumper C2 and sends a transmission wave to the right front of the vehicle.

[0018] The first rear sensor 3E is mounted near the left end of the rear bumper C3 and transmits a transmission wave to the left rear of the vehicle. The second rear sensor 3F is mounted between the first rear sensor 3E and the vehicle width center line LC in the vehicle width direction and transmits a transmission wave to the short rear of the vehicle. The third rear sensor 3G is mounted symmetrically with the second rear sensor 3F across the vehicle width center line LC. The third rear sensor 3G is mounted between the vehicle width center line LC and the fourth rear sensor 3H in the vehicle width direction and transmits a transmission wave to the rear of the vehicle. The fourth rear sensor 3H is mounted symmetrically with the first rear sensor 3E across the vehicle width center line LC.The fourth rear sensor 3H is mounted near the right end in the rear bumper C3 and sends a transmission wave to the right rear of the vehicle. Central Unit

[0019] The central unit 2 is an in-vehicle microcomputer with a processor and a memory. With reference to Fig. 2, the central unit 2 has a master-side processor 21, a master-side memory 22 and a master-side communication unit 23.

[0020] The master-side processor 21 performs various control operations by reading and executing programs stored in the master-side memory 22. The master-side memory 22 includes at least one ROM or a non-volatile rewritable memory among various non-volatile tangible storage media, such as ROM, RAM, non-volatile rewritable memory, etc. The non-volatile rewritable memory allows information to be rewritten while the power is on, while the non-volatile rewritable memory holds information that cannot be rewritten while the power is off. The non-volatile rewritable memory is, for example, a flash memory. In addition to the program described above, the master-side memory 22 stores various parameters, such as initial values ​​and / orInitial values ​​required for program execution. The master-side communication unit 23 is a communication interface connected to the communication line 4. The master-side communication unit 23 performs communication based on the DSI3 protocol with the sensor unit 3 under the control of the master-side processor 21. Sensor unit

[0021] With reference to Fig. 2, the sensor unit 3 has a sensor-side processor 31, a sensor-side memory 32, and a sensor-side communication unit 33. The sensor-side processor 31 reads and executes the program stored in the sensor-side memory 32 to control the overall operation of the sensor unit 3. The sensor-side memory 32 includes at least one ROM or a non-volatile rewritable memory among various non-volatile tangible storage media, such as ROM, RAM, non-volatile rewritable memory, and the like. In addition to the program described above, the sensor-side memory 32 stores various parameters, such as initial values, required for program execution.The sensor-side communication unit 33 is a communication interface connected to the communication line 4 and performs communication based on the DSI3 protocol with the central unit 2 under the control of the sensor-side processor 31.

[0022] The sensor unit 3 also includes a transmitter circuit 34, a receiver circuit 35, and a transceiver 36. The transmitter circuit 34 applies a drive signal to the transmitter / receiver 36 to generate a probe wave at the transmitter / receiver 36 in a transmission mode to transmit probe waves to the outside. The receiver circuit 35 performs various signal processing, such as amplification, filtering, etc., on the received signal generated by the transmitter / receiver 36 according to the reception status of the reflected wave in the reception mode to receive the reflected wave. The transmitter / receiver 36 generates a probe wave by applying the drive signal from the transmitter circuit 34 in the transmission mode. The transmitter / receiver 36 generates a reception signal in response to receiving the reflected wave in the reception mode.In this embodiment, the transmitter / receiver 36 is a so-called resonant ultrasonic microphone with a built-in electro-mechanical energy conversion element, such as a piezoelectric element.

[0023] The sensitivity of the sensor unit 3 is adjusted to change with the passage of time during the detection operation. For example, the sensor unit 3 may perform STC, in which the sensitivity of the transmission of the probe wave from the transmitter / receiver 36 changes with the passage of time. STC stands for Sensitivity Time Control. For example, the sensor-side processor 31 may adjust the gain in the amplifier provided in the receiver circuit 35 according to the method described in (i) in Fig. 4, which is stored in the sensor-side memory 32, change over time. Communication control device

[0024] Fig. 3 shows the functional configuration of the communication control device 50, which is realized by executing a program in at least one of the processors, master-side processor 21 and sensor-side processor 31, shown in Fig. 2. The communication control device 50 controls communication between the central unit 2 and the sensor unit 3. The communication control device 50 has a sensitivity acquisition unit 51 and a communication control unit 52.

[0025] The sensitivity acquisition unit 51 acquires the sensitivity status of the sensor unit 3 during a sensing operation. The sensitivity status can be defined as either a predetermined high sensitivity status or a low sensitivity status lower than the high sensitivity status. For example, the sensitivity acquisition unit 51 detects a low sensitivity interval, which is a period of time during which the sensitivity is in the low sensitivity status. The high sensitivity status and the low sensitivity status are described below. The communication control unit 52 controls the communication timing of communication signals between the central unit 2 and the sensor unit 3.The communication control unit 52 communicates special communication signals, which are communication signals that are a noise source in the detection operation by the sensor unit 3 when the sensitivity status is in the low sensitivity status. The communication control unit 52 communicates non-special communication signals that are different from the special communication signals when the sensitivity status is either the high communication status or the low communication status.

[0026] The special communication signals include a command signal sent from the central unit 2 to the sensor unit 3, and a response signal sent from the sensor unit 3 to the central unit 2 in response to the command signal. Non-special communication signals include detection result signals corresponding to the results of detection operations by the sensor unit 3. In other words, the special communication signals are communication signals transmitted and received in the CRM mode, which is an example of the first communication mode (i.e., CRM signals). On the other hand, the non-special communication signals are communication signals transmitted and received in the PDCM mode, which is an example of the second communication mode (i.e., PDCM signals). Overview of the operation

[0027] The following is an overview of an operation of the device configuration, method and program of this embodiment using the Fig. 4 shown time diagram. In Fig. 4 shows (i) the time variation of the gain sensitivity status in the sensor unit 3, (ii) shows an example of signal communications in a comparative example, and (iii) shows an example of signal communications in this embodiment. In the figure, G on the vertical axis in (i) represents gain, and t on the horizontal axis represents time. In (ii) and (iii), "M.EXE" represents Measurement Execute. A Measurement Execute command is a detection start signal to start the detection operation in the sensor unit 3. "MODE" represents the communication mode. Since the timing on the horizontal axis in (i) corresponds to the communication timing and communication mode of each signal in (ii) and (iii), (i) to (iii) are arranged side by side in Fig. 4 can be seen.

[0028] The detection operation in the sensor unit 3 starts when the central unit 2 transmits a detection start signal, which is a CRM signal, and the sensor unit 3 receives the detection start signal. In the detection operation, the sensor unit 3 causes the transmitter / receiver 36 to transmit the probe wave and performs the reception operation of the wave reflected from the object B of the probe wave. First, the sensor unit 3 performs the measurement of electrical noise and acoustic noise in the sensor unit 3 during the period from the start time t0 of the detection operation to the time t1 when the predetermined time elapses. During the noise measurement from time t0 to t1, the sensitivity or gain is set to the highest value Gmax. Next, after time t1, when the noise measurement is completed, the sensor unit 3 performs the object detection operation.From time t1 to t2, the probe wave transmission operation is performed, and the waiting time from the end of the transmission operation to the reverberation convergence is included in this period. During this period, the sensitivity or gain is set to the minimum value Gmin. After time t2, the reception operation is performed. Here, during the period from time t2 to t3, the sensitivity or gain gradually increases from the minimum value Gmin to the maximum value Gmax and is maintained at the maximum value Gmax for a predetermined period after time t3. This increases the sensitivity to the wave reflected from the object B. The sensor unit 3 then transmits the PDCM signal corresponding to the reception result of the reflected wave, i.e., the detection result of the object B, to the central unit 2.

[0029] The one in (ii) in Fig. The comparative example shown in Figure 4 shows the case where this embodiment is not applied. Here, the Measurement Execute command or the detection start signal is the CRM signal. Therefore, as shown in the timing chart in (ii), Fig. 4, in the comparative example, the communication mode has already been switched from the PDCM mode to the CRM mode by the time the detection start signal is transmitted and received. On the other hand, in order to receive the PDCM signal from the sensor unit 3, the communication mode must have been switched to the PDCM mode. Therefore, the central unit 2 sends a mode change signal to the sensor unit 3 to change the communication mode from the CRM mode to the PDCM mode, which is indicated as "CRM1" in the figure. This causes the communication mode to be switched from the CRM mode to the PDCM mode.

[0030] In the PDCM mode, the PDCM signals transmitted from the sensor unit 3 to the central unit 2 and received by the central unit 2 are assigned sequential codes in the chronological order of transmission and reception, such as PDCM1 signal, PDCM2 signal, PDCM3 signal, etc. A BRC trigger signal, which is the trigger signal transmitted from the central unit 2 to the sensor unit 3 for transmitting the PDCM signal, is omitted from the figure to avoid complicating the figure. BRC stands for Broadcast Read Command. To change the detection operation conditions in the sensor unit 3 (e.g., probe wave frequency, transmission / reception period, etc.), it is necessary to transmit a detection condition setting signal from the central unit 2 to the sensor unit 3. The detection condition setting signal is the CRM signal to set the detection operation conditions in the sensor unit 3.Therefore, the central unit 2 sends the CRM signal, shown as "CRM2" in the figure, to the sensor unit 3. The CRM2 signal includes a mode change signal for changing the communication mode from the PDCM mode to the CRM mode, and the detection condition setting signal that takes effect after the mode change signal is sent and received.

[0031] During communication between the central unit 2 as the master device and the sensor unit 3 as the slave device, noise may occur. Here, the communication that may be a source of noise is primarily the communication of signals in the CRM mode, including the transmission of commands from the central unit 2 to the sensor unit 3 and their responses from the sensor unit 3 to the central unit 2. Noise may generate false detections in the sensor unit 3. In particular, as in (ii) in Fig. As shown in Figure 4, when the CRM2 signal, which is a communication signal that is a noise source, is transmitted and received in a high sensitivity state with high gain, there is a concern about the occurrence of false detection due to noise. On the other hand, if communication between the central unit 2 and the sensor unit 3 is not performed at all during the detection operation of the sensor unit 3, the detection performance will be limited due to the longer detection operation cycle.

[0032] Therefore, as in (iii) in Fig. As shown in Figure 4, this embodiment detects the CRM signal, which is a communication signal that is a noise source in the detection operation by the sensor unit 3, only when it is in a low sensitivity state. Here, for example, the "high sensitivity state" may be a state where the gain is set above a predetermined gain threshold, and the "low sensitivity state" may be a state where the gain is set below the gain threshold. Or, for example, the "high sensitivity state" may be a state where the gain is at the highest value Gmax, and the "low sensitivity state" may be a state where the gain is below the highest value Gmax.In this regard, the sensitivity acquisition unit 51 may, for example, detect the timing of the occurrence of the low sensitivity section based on the transmission / reception time of the Measurement Execute command. The communication control unit 52 then sets the timing of transmission and reception of CRM signals within the low sensitivity section. Specifically, for example, the communication control unit 52 may acquire the CRM signal containing the detection condition setting signal, such as the CRM2 signal in the comparative example in (ii) in FIG. Fig. 4 communicate between time t1 and t2, that is, during the low sensitivity period when the gain is set to the lowest value Gmin. This makes it possible to avoid false detection in the sensor unit 3 even if the CRM signal, which is a noise source, is communicated during the detection operation in the sensor unit 3, and to improve the short-range detection performance by shortening the detection operation cycle.

[0033] In this embodiment, the PDCM signal, which is a communication signal that is hardly a noise source in the detection operation, is transmitted and received regardless of the sensitivity state. Therefore, the PDCM signals can be transmitted and received not only in the low sensitivity state but also in the high sensitivity state. This makes it possible to further improve the short-range detection performance by shortening the detection operation cycle.

[0034] When the CRM signal is received during the PDCM mode, this embodiment performs the processing corresponding to the received CRM signal. As in (iii) in Fig. 4, this makes it possible to transmit and receive the detection start signals regardless of the communication mode. Accordingly, it is not necessary for the communication mode to be switched from the PDCM mode to the CRM mode at the time of transmitting and receiving the detection start signal. Furthermore, the communication mode does not need to be switched from the PDCM mode to the CRM mode when the CRM signals including the detection condition setting signals are transmitted and received in the low sensitivity state during the detection operation of the sensor unit 3. Thus, according to this embodiment, it is possible to suppress the communication volume by reducing the number of times the mode change signal is transmitted and received to switch the communication mode from the PDCM mode to the CRM mode.and it is also possible to further improve the short-range detection performance by shortening the detection duty cycle.

[0035] The PDCM signals are assigned sequential codes in the chronological order of transmission and reception during a series of detection operations, i.e., from the time of transmission and reception of the Measurement Execute command to the time of transmission and reception of the Measurement Stop command. The Measurement Stop command is a detection end signal to terminate the detection operation in the sensor unit 3. This system resets the code to be assigned next to the initial value by transmitting and receiving a reset signal, which is the CRM signal, and does not reset the code to the initial value even if the CRM signal, which is different from the reset signal, is transmitted and received. The "reset signal" is either the detection start signal or the detection end signal. As shown in (iii) in Fig. As can be seen in Fig. 4, when the CRM signal is transmitted or received immediately after the PDCM2 signal, but the CRM signal is not the reset signal, the PDCM signal immediately afterward is the PDCM3 signal. Consequently, even if the CRM signal is transmitted and received in a low sensitivity state during a series of detection operations, the sign of the sequential number assigned to the PDCM signal is prevented from being accidentally reset in the process. Therefore, according to this embodiment, it is possible for the central unit 2 to obtain data from the plurality of sensor units 3 in a proper manner.

[0036] This embodiment switches from the CRM mode to the PDCM mode not only when a mode change signal is transmitted or received, but also when the detection start signal or the detection condition setting signal is transmitted or received. This makes it possible to suppress or inhibit the communication volume by reducing the number of times the mode change signals are transmitted and received, and it also makes it possible to further improve the short-range detection performance by shortening the detection operation cycle.

[0037] Fig. Figure 5 is a flowchart showing the process of switching the communication mode. "S" stands for step. Fig. The flowchart shown in Figure 5 is used to explain the process related to switching communication modes. First, at step 501, the communication control unit 52 determines whether the current communication mode is the CRM mode.

[0038] If the current communication mode is the CRM mode (i.e., step 501 = Yes), the communication control unit 52 executes the processing of step 502. At step 502, the communication control unit 52 determines whether the mode change command, i.e., the mode change signal, has been transmitted and received. If the mode change signal has been transmitted and received (i.e., step 502 = Yes), the communication control unit 52 executes the processing of step 503 to temporarily terminate the processing related to switching the communication mode. At step 503, the communication control unit 52 switches the communication mode from the CRM mode to the PDCM mode. If the mode change signal has not been transmitted and received (i.e., step 502 = No), the communication control unit 52 executes the process of step 504.At step 504, the communication control unit 52 determines whether the Measurement Execute command, ie, the detection start signal, has been transmitted and received. If the detection start signal has been transmitted and received (ie, step 504 = Yes), the communication control unit 52 executes the processing of step 503 to temporarily terminate the processing related to switching the communication mode. If the detection start signal has not been transmitted and received (ie, step 504 = No), the communication control unit 52 executes the processing of step 505. At step 505, the communication control unit 52 determines whether the Measurement Set command, ie, a detection condition setting signal, has been transmitted and received. If the detection condition setting signal has been transmitted and received (ie,If the detection condition setting signal is not transmitted and received (i.e., step 505 = Yes), the communication control unit 52 executes the processing of step 503 to temporarily terminate the communication mode switching processing. On the other hand, if the detection condition setting signal has not been transmitted and received (i.e., step 505 = No), the communication control unit 52 skips the processing of step 503 and terminates the communication mode switching processing once and for all.

[0039] If the current communication mode is the PDCM mode (ie, step 501 = No), the communication control unit 52 executes the processing of step 506. In step 506, the communication control unit 52 determines whether the mode change command, ie, the mode change signal, has been transmitted and received. If the mode change signal has been transmitted and received (ie, step 506 = Yes), the communication control unit 52 executes the processing of step 507 to temporarily terminate the processing related to switching the communication mode. In step 507, the communication control unit 52 switches the communication mode from the PDCM mode to the CRM mode. If the mode change signal has not been transmitted and received (ie,Step 506 = No), the communication control unit 52 skips the processing of step 507 and terminates the processing related to switching the communication mode once and for all.

[0040] The present disclosure is not limited to the above embodiment. Therefore, any modifications to the above embodiment are possible. Representative variations are described below. In the following description of variations, differences from the above embodiment will be primarily explained. In the above embodiments and variations, the same symbols are assigned to the parts that are identical or the same to each other. Therefore, in the following description of variations, the description in the above embodiment can be appropriately applied to the components having the same symbols as those in the above embodiment unless there is technical inconsistency or special additional explanation.

[0041] The present disclosure is not limited to the specific device configuration seen in the above embodiments. The disclosure is not limited to the specific device configurations seen in the above embodiments.

[0042] All or part of the functional configuration implemented by the master-side processor 21 and the master-side memory 22 in the central unit 2 can be replaced by digital circuits such as ASICs and FPGAs. FPGA stands for Field Programmable Gate Array. In other words, the in-vehicle microcomputer section and the digital circuit section can coexist in the central unit 2. The same applies to the sensor unit 3.

[0043] Alternatively, the program can be downloaded or updated via V2X communication. V2X stands for Vehicle to X. Alternatively, the program can be downloaded or updated via a terminal device at a manufacturing facility, maintenance depot, dealer, etc. of vehicle C. The program can be stored on a memory card, optical disk, magnetic disk, or the like.

[0044] Each of the above functional configurations and processes may be implemented by a dedicated computer provided by configuring a processor and a memory programmed to perform one or more functions embodied by the computer program. Alternatively, each of the above functional configurations and processing may be implemented by a dedicated computer provided by configuring the processor with one or more dedicated hardware logic circuits. Alternatively, each of the above functional configurations and processing may be implemented by one or more dedicated computers provided by a combination of a processor and a memory programmed to perform one or more functions, and a processor configured by one or more dedicated hardware logic circuits.The computer program may also be stored on a computer-readable, non-transitory, tangible storage medium as instructions to be executed by a computer. In other words, each of the above functional configurations and processes may be expressed as a computer program containing procedures for implementing them, or as a non-transitory, tangible storage medium storing the program.

[0045] Therefore, the sensitivity acquisition unit 51 and the communication control unit 52, which are Fig. 3, only functional configuration blocks are shown, which are arranged for convenience to contribute to the understanding of the content of this disclosure. Therefore, even if these functional configuration blocks are not actually implemented in the central unit 2 and / or the sensor unit 3 as routines or hardware, it is sufficient if the functions or processing prescribed in this disclosure are implemented.

[0046] The connection method between the central unit 2 as the master device and the sensor unit 3 as the slave device is not limited to DSI, but may also be PSI. PSI stands for Peripheral Sensor Interface. There is no limitation on the version of DSI or PSI, however, it is appropriate to use the latest version at the time of implementation, such as DSI3 or PSI5 at the time of filing this application. Thus, the present disclosure is widely applicable to time-division multiple access, or TDMA.

[0047] For example, three sensor units 3 may be mounted on each of the front bumper C2 and rear bumper C3. Or, for example, five or more sensor units 3 may be mounted on the front bumper C2 and / or rear bumper C3. Or, for example, the sensor units 3 may be mounted on the side of the vehicle body C1.

[0048] There are no restrictions on the specific configuration or use of the sensor unit 3. For example, the sensor unit 3 is not limited to an integrated transmitter / receiver type in which a single transmitter / receiver 36 performs the transmission / reception operation, but may be configured with a transmitter / receiver 36 for transmission and a receiver 36 for reception installed separately in a single housing. Additionally, one of the multiple sensor units 3 may be used for transmission and the other for reception. In this case, the sensor unit 3 for transmission and the sensor unit 3 for reception can be exchanged or replaced as needed over time.

[0049] Sensor unit 3 is not limited to so-called ultrasonic sensors. For example, sensor unit 3 can be a radar sensor. Sensor unit 3 is not limited to so-called distance measuring sensors. In particular, sensor unit 3 can be, for example, a collision detection sensor in an airbag system.

[0050] The present disclosure is not limited to the specific operating modes seen in the above embodiments. That is, for example, the manner in which the gain or sensitivity changes over time is not limited to the specific example shown in (i) in Fig.4. In particular, for example, the manner in which the gain increases between time t2 and t3 is not limited to the step-like manner seen in the figure, but may be linear or curved. The sensitivity acquisition unit 51 may also be capable of determining whether the sensitivity status is in a high sensitivity status or a low sensitivity status at a given processing timing by the processor. In this case, the sensitivity acquisition unit 51 may be referred to as the "sensitivity determination unit."

[0051] The terms "more than" and "greater than" are interchangeable. Similarly, "less than" and "fewer than" are interchangeable. Similar concepts such as "acquire," "compute," "detect," and "capture" are also interchangeable, as long as they are not technically inconsistent or inappropriate.

[0052] It should be understood that the elements comprising the above embodiments are not necessarily indispensable unless they are expressly stated to be indispensable or unless they are clearly indispensable in principle. In addition, when numerical values ​​of the number, amount, range, etc. of components are mentioned, this disclosure is not limited to such specific values ​​unless they are expressly stated to be particularly essential or unless they are clearly limited to specific values ​​in principle. Similarly, when the shape, direction, positional relationship, etc. of a component is mentioned, the disclosure is not limited to that shape, direction, positional relationship, etc., except in cases where it is expressly stated to be particularly essential in principle or limited to a specific shape, direction, positional relationship, etc.

[0053] Variations are also not limited to the above examples. For example, multiple variations may be combined with each other as long as they are not technically inconsistent. Furthermore, all or part of the above embodiments and all or part of the variations may be combined with each other as long as they are not technically inconsistent.

[0054] As can be seen from the above description, the present disclosure includes at least the following aspects. <Aspekt 1-1>

[0055] A communication control device (50) configured to control communication between a central unit (2) and a sensor unit (3) in a sensor system (1), the sensor system comprising the central unit as a master device and the sensor unit as a slave device, the communication control device (50) comprising: a sensitivity acquisition unit (51) that acquires a sensitivity status of the sensor unit during a detection operation in the sensor unit, wherein the sensitivity status is defined as either a high sensitivity status or a low sensitivity status lower than the high sensitivity status; and a communication control unit (52) that communicates special communication signals when the sensitivity obtaining unit obtains the low sensitivity status, wherein the special communication signals are communication signals that are noise sources in the detection operation. <Aspekt 1-2>

[0056] In the case of aspect 1-1, the sensitivity status changes with the passage or progression of time during the sensing operation. <Aspekt 1-3>

[0057] In aspect 1-1 or 1-2, the special communication signals include a command signal sent from the central unit to the sensor unit and a response signal sent from the sensor unit to the central unit in response to the command signal. <Aspekt 1-4>

[0058] In any one of aspects 1-1 to 1-3, the communication control unit communicates non-special communication signals different from the special communication signals when the sensitivity obtaining unit obtains the high sensitivity status. <Aspekt 1-5>

[0059] In the aspect 1-4, the special communication signals include a reset signal and a non-reset signal, and the sensor system assigns a sequential number code to the non-special communication signals in the chronological order of sending and receiving, In response to the sending and receiving of the reset signal among the special communication signals, the sensor system resets the sequential number code to its initial value, and In response to the transmission and reception of the non-reset signal among the special communication signals, the sensor system does not reset the sequential number code to its initial value. <Aspekt 1-6>

[0060] In aspect 1-4 or 1-5, the non-special communication signals include a detection result signal indicating the result of the detection operation by the sensor unit. <Aspekt 1-7>

[0061] In any of aspects 1-4 to 1-6, the sensor system is switchable between a first communication mode enabling bidirectional communication between the central unit and the sensor unit and a second communication mode enabling one-way communication from the sensor unit to the central unit, the sensor system switches from the first communication mode to the second communication mode when the sensor unit receives a trigger signal from the central unit, the special communication signals are sent and received in the first communication mode, and the non-special communication signals are sent and received in the second communication mode. <Aspekte 1-8>

[0062] In aspect 1-7, the first communication mode is a command response mode in the DSI protocol, and The second communication mode is a periodic data collection mode in the DSI protocol. <Aspekt 1-9>

[0063] In aspect 1-7 or 1-8, the sensor system switches from the first communication mode to the second communication mode when a mode change signal to change the communication mode from the first communication mode to the second communication mode, a detection start signal to start the detection operation in the sensor unit, or a detection condition setting signal to set conditions for the detection operation in the sensor unit, each of which is one of the specific communication signals, is transmitted and received. <Aspekt 1-10>

[0064] In any one of aspects 1-7 to 1-9, when the sensor system receives the specific communication signals in the second communication mode, it performs an operation according to the specific communication signals. <Aspekt 1-11>

[0065] In any one of aspects 1-1 to 1-10, the sensor unit is a detection sensor for an object (B) that receives a wave of an exploration wave reflected from an object. <Aspekt 1-12>

[0066] In aspects 1-11, the sensor unit is mounted on a vehicle (C) to detect objects around the vehicle. <Aspekt 2-1 >

[0067] A communication control method for controlling communication between a central unit (2) and a sensor unit (3) in a sensor system (1), the sensor system having the central unit as a master device and the sensor unit as a slave device, the communication control method comprising: obtaining a sensitivity status of the sensor unit during a detection operation in the sensor unit, wherein the sensitivity status is defined as either a high sensitivity status or a low sensitivity status that is lower than the high sensitivity status; and communicating special communication signals when the low sensitivity status is acquired, wherein the special communication signals are communication signals that are noise sources in the detection operation. <Aspekt 2-2>

[0068] In the case of aspect 2-1, the sensitivity status changes with the passage or progression of time during the sensing operation. <Aspekt 2-3>

[0069] In aspect 2-1 or 2-2, the special communication signals include a command signal sent from the central unit to the sensor unit and a response signal sent from the sensor unit to the central unit in response to the command signal. <Aspekt 2-4>

[0070] In any one of aspects 2-1 to 2-3, the communication control unit communicates non-special communication signals different from the special communication signals when the sensitivity obtaining unit obtains the high sensitivity status. <Aspekt 2-5>

[0071] In aspect 2-4, the special communication signals include a reset signal and a non-reset signal, and the sensor system assigns a sequential number code to the non-special communication signals in the chronological order of sending and receiving, In response to the sending and receiving of the reset signal among the special communication signals, the sensor system resets the sequential number code to its initial value, and In response to the transmission and reception of the non-reset signal among the special communication signals, the sensor system does not reset the sequential number code to its initial value. <Aspekt 2-6>

[0072] In aspect 2-4 or 2-5, the non-special communication signals include a detection result signal indicating the result of the detection operation by the sensor unit. <Aspekt 2-7>

[0073] In any of aspects 2-4 to 2-6, the sensor system is switchable between a first communication mode enabling bidirectional communication between the central unit and the sensor unit and a second communication mode enabling one-way communication from the sensor unit to the central unit, the sensor system switches from the first communication mode to the second communication mode when the sensor unit receives a trigger signal from the central unit, the special communication signals are sent and received in the first communication mode, and the non-special communication signals are sent and received in the second communication mode. <Aspekte 2-8>

[0074] In aspect 2-7, the first communication mode is a command response mode in the DSI protocol, and The second communication mode is a periodic data collection mode in the DSI protocol. <Aspekt 2-9>

[0075] In aspect 2-7 or 2-8, the sensor system switches from the first communication mode to the second communication mode when a mode change signal to change the communication mode from the first communication mode to the second communication mode, a detection start signal to start the detection operation in the sensor unit, or a detection condition setting signal to set conditions for the detection operation in the sensor unit, each of which is one of the specific communication signals, is transmitted and received. <Aspekt 2-10>

[0076] In any one of aspects 2-7 to 2-9, when the sensor system receives the specific communication signals in the second communication mode, it performs an operation according to the specific communication signals. <Aspekt 2-11 >

[0077] In any one of aspects 2-1 to 2-10, the sensor unit is a detection sensor for an object (B) that receives a wave of an exploration wave reflected from an object. <Aspekt 2-12>

[0078] In aspects 2-11, the sensor unit is mounted on a vehicle (C) to detect objects around the vehicle. <Aspekt 3-1>

[0079] A communication control program to be executed by a communication control device (50) that controls communication between a central unit (2) and a sensor unit (3) in a sensor system (1), the sensor system having the central unit as a master device and the sensor unit as a slave device, the communication control program causing the communication control device (50) to execute: obtaining a sensitivity status of the sensor unit during a detection operation in the sensor unit, wherein the sensitivity status is defined as either a high sensitivity status or a low sensitivity status that is lower than the high sensitivity status; and communicating special communication signals when the low sensitivity status is acquired, wherein the special communication signals are communication signals that are noise sources in the detection operation. <Aspekt 3-2>

[0080] In the case of aspect 3-1, the sensitivity status changes with the passage or progression of time during the sensing operation. <Aspekt 3-3>

[0081] In aspect 3-1 or 3-2, the special communication signals include a command signal sent from the central unit to the sensor unit and a response signal sent from the sensor unit to the central unit in response to the command signal. <Aspekt 3-4>

[0082] In any one of aspects 3-1 to 3-3, the communication control unit communicates non-special communication signals different from the special communication signals when the sensitivity obtaining unit obtains the high sensitivity status. <Aspekt 3-5>

[0083] In aspect 3-4, the special communication signals include a reset signal and a non-reset signal, and the sensor system assigns a sequential number code to the non-special communication signals in the chronological order of sending and receiving, In response to the sending and receiving of the reset signal among the special communication signals, the sensor system resets the sequential number code to its initial value, and In response to the transmission and reception of the non-reset signal among the special communication signals, the sensor system does not reset the sequential number code to its initial value. <Aspekt 3-6>

[0084] In aspect 3-4 or 3-5, the non-special communication signals include a detection result signal indicating the result of the detection operation by the sensor unit. <Aspekt 3-7>

[0085] In any of aspects 3-4 to -6, the sensor system is switchable between a first communication mode enabling bidirectional communication between the central unit and the sensor unit and a second communication mode enabling one-way communication from the sensor unit to the central unit, the sensor system switches from the first communication mode to the second communication mode when the sensor unit receives a trigger signal from the central unit, the special communication signals are sent and received in the first communication mode, and the non-special communication signals are sent and received in the second communication mode. <Aspekte 3-8>

[0086] In aspect 3-7, the first communication mode is a command response mode in the DSI protocol, and The second communication mode is a periodic data collection mode in the DSI protocol. <Aspekt 3-9>

[0087] In aspect 3-7 or 3-8, the sensor system switches from the first communication mode to the second communication mode when a mode change signal to change the communication mode from the first communication mode to the second communication mode, a detection start signal to start the detection operation in the sensor unit, or a detection condition setting signal to set conditions for the detection operation in the sensor unit, each of which is one of the specific communication signals, is transmitted and received. <Aspekt 3-10>

[0088] In any one of aspects 3-7 to 3-9, when the sensor system receives the specific communication signals in the second communication mode, it performs an operation according to the specific communication signals. <Aspekt 3-11 >

[0089] In any one of aspects 3-1 to 3-10, the sensor unit is a detection sensor for an object (B) that receives a wave of an exploration wave reflected from an object. <Aspekt 3-12>

[0090] In aspects 3-11, the sensor unit is mounted on a vehicle (C) to detect objects around the vehicle QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] JP 2022-079069

[0001] JP 6894043B

[0004]

Claims

[1] A communication control device configured to control communication between a central unit and a sensor unit in a sensor system, the sensor system having the central unit as a master device and the sensor unit as a slave device, the communication control device comprising: a sensitivity acquisition unit that acquires a sensitivity status of the sensor unit during a detection operation in the sensor unit, wherein the sensitivity status is defined as either a high sensitivity status or a low sensitivity status lower than the high sensitivity status; and a communication control unit that communicates special communication signals when the sensitivity obtaining unit obtains the low sensitivity status, wherein the special communication signals are communication signals that are noise sources in the detection operation. [2] The communication control device according to claim 1, wherein the sensitivity status changes with the passage of time during the detection operation. [3] A communication control device according to claim 1, wherein the special communication signals include a command signal sent from the central unit to the sensor unit and a response signal sent from the sensor unit to the central unit in response to the command signal. [4] The communication control device according to claim 1, wherein the communication control unit communicates non-special communication signals different from the special communication signals when the sensitivity obtaining unit obtains the high sensitivity status. [5] Communication control device according to claim 4, wherein the special communication signals include a reset signal and a non-reset signal, and the sensor system assigns a sequential number code to the non-special communication signals in the chronological order of sending and receiving, the sensor system resets the sequential number code to its initial value in response to the transmission and reception of the reset signal among the special communication signals, and the sensor system does not reset the sequential number code to its initial value in response to the transmission and reception of the non-reset signal among the special communication signals. [6] The communication control device according to claim 4, wherein the non-special communication signals include a detection result signal indicating the result of the detection operation by the sensor unit. [7] Communication control device according to claim 4, wherein the sensor system is switchable between a first communication mode, which enables bidirectional communication between the central unit and the sensor unit, and a second communication mode, which enables one-way communication from the sensor unit to the central unit, the sensor system switches from the first communication mode to the second communication mode when the sensor unit receives a trigger signal from the central unit, the special communication signals are sent and received in the first communication mode, and the non-special communication signals are sent and received in the second communication mode. [8] Communication control device according to claim 7, wherein the first communication mode is a command response mode in the DSI protocol, and the second communication mode is a periodic data collection mode in the DSI protocol. [9] The communication control device according to claim 7, wherein the sensor system switches from the first communication mode to the second communication mode when a mode change signal for changing the communication mode from the first communication mode to the second communication mode, a detection start signal for starting the detection operation in the sensor unit, or a detection condition setting signal for setting conditions for the detection operation in the sensor unit, each of which is one of the special communication signals, is transmitted and received. [10] The communication control device according to claim 7, wherein the sensor system, when receiving the specific communication signals in the second communication mode, performs an operation according to the specific communication signals. [11] The communication control device according to claim 1, wherein the sensor unit is an object detection sensor that receives a wave of an exploration wave reflected from an object. [12] The communication control device according to claim 11, wherein the sensor unit is mounted on a vehicle and detects the object present around the vehicle. [13] A communication control method for controlling communication between a central unit and a sensor unit in a sensor system, the sensor system having the central unit as a master device and the sensor unit as a slave device, the communication control method comprising: obtaining a sensitivity status of the sensor unit during a detection operation in the sensor unit, wherein the sensitivity status is defined as either a high sensitivity status or a low sensitivity status that is lower than the high sensitivity status; and communicating special communication signals when the low sensitivity status is acquired, wherein the special communication signals are communication signals that are noise sources in the detection operation. [14] A communication control program to be executed by a communication control device that controls communication between a central unit and a sensor unit in a sensor system, the sensor system having the central unit as a master device and the sensor unit as a slave device, the communication control program causing the communication control device to execute: obtaining a sensitivity status of the sensor unit during a detection operation in the sensor unit, wherein the sensitivity status is defined as either a high sensitivity status or a low sensitivity status that is lower than the high sensitivity status; and communicating special communication signals when the low sensitivity status is acquired, wherein the special communication signals are communication signals that are noise sources in the detection operation.

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