JP6527541B2 - Transmitter - Google Patents

Description

  The present invention relates to a transmitter capable of detecting its own abnormality.

  Patent Document 1 aims to provide a communication system and a communication method that can determine the correctness / incorrectness of a message being communicated in a communication system with a simple configuration ([0009]). In order to achieve the object, in the communication system of Patent Document 1 (abstract), a plurality of ECUs are connected to a communication bus so that messages can be communicated. In each ECU, a communication interval defined for the message to be communicated is set, and the ECU that transmits the message transmits a message based on the defined communication interval. The ECU that receives the transmitted message detects the communication interval of the received message, and determines the correctness / incorrectness of the received message based on the comparison between the detected communication interval and the defined communication interval. Do.

  The periodically transmitted message is assumed to include data based on detection values of various sensors, and data based on information from information-related equipment ([0042]).

International Publication No. 2013/094072 brochure

  As described above, in Patent Document 1, the ECU that receives a message including data etc. (control parameter) based on detection values of various sensors detects a communication interval of the received message, and is defined as the detected communication interval. Based on the comparison with the communication interval, the correctness / incorrectness of the received message is determined (summary). In other words, in Patent Document 1, the correctness / incorrectness of the message is determined on the receiving device side.

  However, if the receiver determines the correctness / incorrectness of the message, the time lag after the transmission of the message from the transmitter becomes long. Also, in order to determine the correctness / incorrectness of the message only on the receiving device side, it is necessary for all the receiving devices to be able to make such determination, which tends to lead to an increase in cost.

  Such an issue may apply not only to vehicles but also to other communication networks.

  The present invention has been made in consideration of the above problems, and provides a transmitting device capable of at least one of quickly responding to transmission abnormality in the transmitting device and suppressing an increase in cost. With the goal.

The transmitter according to the present invention is
A transmission control unit that transmits a signal to the communication network a predetermined number of times within a predetermined period ;
In front Symbol within a predetermined time period, number of times of transmission of the signal by the transmission control unit, when it exceeds the predetermined number, an abnormality detecting unit that stops transmission of the signal by the transmission control unit,
Equipped with

  According to the present invention, the abnormality detection unit of the transmission device stops the transmission of the signal when the signal is transmitted more than the originally intended number of transmissions. As a result, it is possible to determine abnormality of the transmission control unit not on the receiving device side but on the transmitting device side. Therefore, it is possible to promptly cope with the transmission abnormality in the transmission apparatus. In addition, since the transmission device itself detects a transmission abnormality in the transmission device, it is possible to cope with only one transmission device, and it is possible to suppress an increase in cost.

The transmitter according to the present invention is
A transmission control unit that transmits a signal to the communication network a predetermined number of times within a predetermined period;
An abnormality detection unit that stops transmission of the signal by the transmission control unit when the number of transmissions of the signal by the transmission control unit exceeds the predetermined number within the predetermined period;
Equipped with
The signal includes identification information indicating the nature of the signal,
The transmission control unit
Transmitting a first signal including first identification information a first predetermined number of times within the predetermined period;
Transmitting a second signal including second identification information a second predetermined number of times within the predetermined period;
The abnormality detection unit
The first number of transmissions, which is the number of transmissions of the first signal in the predetermined period, and the second number of transmissions, which is the number of transmissions of the second signal in the predetermined period, are counted.
Based on the comparison result of the first number of transmissions and the second number of transmissions, it is determined whether it is necessary to stop transmission of the first signal and the second signal.
It is characterized by
As a result, it is possible to determine abnormality of the transmission control unit not on the receiving device side but on the transmitting device side. Therefore, it is possible to promptly cope with the transmission abnormality in the transmission apparatus. In addition, since the transmission device itself detects a transmission abnormality in the transmission device, it is possible to cope with only one transmission device, and it is possible to suppress an increase in cost. Moreover, it becomes possible to determine abnormality of signal transmission based on the comparison result of the frequency | count of transmission of two types of signals by this.

  The first number of transmissions may be greater than, less than, or equal to the second number of transmissions. The abnormality detection unit may determine whether it is necessary to stop transmission of the first signal and the second signal based on a ratio between the first number of transmissions and the second number of transmissions in the predetermined period. This makes it easy to determine whether or not the transmission timing is out of the normal range even if both the first signal and the second signal are delayed due to some influence.

  According to the present invention, it is possible to realize at least one of quickly responding to transmission abnormality in the transmission apparatus and suppressing an increase in cost.

1 is a schematic overall configuration diagram of a part of a vehicle including an electronic control device as a transmission device according to an embodiment of the present invention. It is a figure which shows the some task which the 1st electronic control unit of the said embodiment performs. It is a figure which shows the structure of the data frame of the said embodiment. It is a flowchart of the transmission monitoring process in embodiment.

A. One Embodiment <A-1. Configuration>
[A-1-1. overall structure]
FIG. 1 is a schematic overall configuration diagram of a part of a vehicle 10 including electronic control devices 20a to 20c as transmitting devices according to an embodiment of the present invention. The electronic control devices 20a to 20c (hereinafter referred to as "ECUs 20a to 20c" or "first to third ECUs 20a to 20c") are also referred to as a communication network 12 in the vehicle 10 (hereinafter referred to as "network 12" or "in-vehicle network 12"). Belongs to). Also, the network 12 may be applied to other than the vehicle 10.

[A-1-2. In-car network 12]
(A-1-2. Overview of in-car network 12)
The in-vehicle network 12 is a CAN (Controller Area Network). Alternatively, the network 12 may be FlexRay, LIN (Local Interconnect Network), or the like. Although only one network 12 is shown in FIG. 1, the vehicle 10 may have a plurality of networks 12.

  The in-vehicle network 12 includes a gateway 22 and a communication line 24 in addition to the plurality of ECUs 20 a to 20 c. Hereinafter, the ECUs 20a to 20c are collectively referred to as the ECU 20.

(A-1-2-2. ECUs 20a to 20c)
(Whole structure of A-1-2-2-1. ECUs 20a to 20c)
Each ECU 20 is a transmission / reception device (or node) connected to the communication network 12 (or communication line 24) to transmit / receive various signals to / from other ECUs 20 via the communication network 12. Each ECU 20 may have only a function as a transmitter or a receiver.

  The first ECU 20a controls the control target devices 32a1, 32a2, ... included in its own control target area 30a (hereinafter also referred to as "first control target area 30a"). Similarly, the second and third ECUs 20b and 20c control target devices 32b1, 32b2 and 32c1 included in their own control target areas 30b and 30c (hereinafter also referred to as "second and third control target areas 30b and 30c"). , 32c2 ... to control. Hereinafter, the control target areas 30a, 30b, 30c,... Are collectively referred to as the control target area 30, and the control target devices 32a1, 32a2, 32b1, 32b2, 32c1, 32c2,.

  As the ECUs 20a to 20c, for example, an engine ECU, an electric power steering system ECU (hereinafter referred to as "EPS ECU"), a lane keeping assist system ECU (hereinafter referred to as "LKAS ECU"), a vehicle behavior stabilization control system ECU (hereinafter referred to as It may include a navigation ECU (VSA: Vehicle Stability Assist).

  The engine ECU controls the output of an engine (not shown). The EPS ECU controls an electric power steering system (not shown). The LKAS ECU controls the lane keeping assist system (not shown). The VSA ECU performs control to stabilize the vehicle body using a braking device (not shown). The navigation ECU performs control to guide the route to the target point of the vehicle 10.

  As shown in FIG. 1, the first ECU 20 a includes an input / output unit 50, an arithmetic unit 52, and a storage unit 54. The other ECUs 20b and 20c also have the same configuration as the first ECU 20a, but are not shown in FIG.

(A-1-2-2-2. Input / output unit 50)
The input / output unit 50 inputs and outputs signals. The input / output unit 50 may include an analog / digital converter and a digital / analog converter. The input / output unit 50 has a transmission circuit 60 and a reception circuit 62 for performing communication in the network 12.

(A-1-2-3. Arithmetic unit 52)
Arithmetic unit 52 controls the entire individual ECU 20. For example, the calculation unit 52 of the first ECU 20a controls the entire first ECU 20a. In the control, the calculation unit 52 uses the program and data stored in the storage unit 54. Arithmetic unit 52 includes a central processing unit (CPU). Some of the functions executed by the calculation unit 52 can also be realized using a logic IC (Integrated Circuit).

  As shown in FIG. 1, the computing unit 52 includes first to nth data processing units 80 a to 80 n (n is a natural number of 5 or more, for example, 5 to 10), a transmission control unit 82, and a reception control unit A transmission monitoring unit 86 is provided.

  The first to nth data processing units 80 a to 80 n perform various data processing to control the control target device 32 in the control target area 30. In the present embodiment, the first to nth data processing units 80a to 80n execute the first to nth parameter signal transmission processing to generate first to nth control parameters Pc1 to Pcn. Then, the first to nth data processing units 80a to 80n transmit the generated first to nth control parameters Pc1 to Pcn to the network 12 via the transmission control unit 82. Hereinafter, the first to nth control parameters Pc1 to Pcn will be collectively referred to as control parameters Pc.

  The first to nth control parameters Pc1 to Pcn are parameters indicating the state of the control target. The control target referred to here can be the control target devices 32a1 to 32c2 themselves. Alternatively, the control target may be a specific function (for example, fuel injection). The first to nth data processing units 80 a to 80 n execute their control using control parameters Pc received from other ECUs 20.

  For example, the calculation unit 52 of the engine ECU outputs control parameters Pc (for example, engine rotation speed [rpm], accelerator pedal opening [%]) related to the engine managed by itself to another ECU 20 (for example, EPS ECU) . The ECU 20 having received the control parameter Pc executes its control (for example, driving of an EPS motor not shown) using the control parameter Pc.

  The transmission control unit 82 includes a data frame DF including the first to nth control parameters Pc1 to Pcn generated by the first to nth data processing units 80a to 80n and a parameter ID (message ID) as their identifier. Generate Then, the transmission control unit 82 transmits to the network 12 as the first to nth parameter signals Sp1 to Spn including the data frame DF. Hereinafter, the first to nth parameter signals Sp1 to Spn will be collectively referred to as a parameter signal Sp.

  The reception control unit 84 receives the parameter signal Sp transmitted from the other ECU 20, extracts the control parameter Pc and the parameter ID (message ID), and supplies the control parameter Pc and the parameter ID (message ID) to the first to nth data processing units 80a to 80n.

  The transmission monitoring unit 86 (hereinafter, also referred to as “monitoring unit 86”) is an abnormality detection unit that detects an abnormality in transmission of the parameter signal Sp by the transmission control unit 82. The transmission monitoring unit 86 is configured as a logic IC different from the CPU. Alternatively, the transmission monitoring unit 86 may be configured as part of a program executed by the CPU.

(A-1-2-4. Storage unit 54)
The storage unit 54 stores a program and data used by the operation unit 52, and includes a random access memory (hereinafter referred to as "RAM"). As the RAM, a volatile memory such as a register and a non-volatile memory such as a flash memory can be used. In addition to the RAM, the storage unit 54 may have a read only memory (hereinafter referred to as "ROM").

(A-1-2-3. Gateway 22)
The gateway 22 has a function of connecting a specific in-vehicle network 12 and other communication networks (not shown) (including an in-vehicle network and / or an out-of-vehicle network).

<A-2. Control in each ECU 20a to 20c>
[A-2-1. Outline of control in each ECU 20a to 20c]
The control in each of the ECUs 20a to 20c of the present embodiment will be described. Each of the ECUs 20 a to 20 c performs control on each control target device 32 of its own control target region 30. Further, each of the ECUs 20a to 20c outputs, to the other ECU 20, one of control parameters Pc related to a control target managed by itself, which is also used by the other ECUs 20. The control target referred to here can be the control target devices 32a1 to 32c2 themselves. Alternatively, the control target may be a specific function (for example, fuel injection). The other ECU 20 that has received the control parameter Pc executes its control using the control parameter Pc. In order to facilitate understanding, control of the first ECU 20a will be described below.

[A-2-2. Multiple Tasks in First ECU 20a]
FIG. 2 is a view showing a plurality of tasks executed by the first ECU 20a of the present embodiment. The first ECU 20a processes these tasks (first to nth tasks) in parallel. Although FIG. 2 explicitly shows the first to sixth tasks, other tasks are also processed in parallel.

  As shown in FIG. 2, the first task (step S11) is a first parameter signal transmission process. In the first parameter signal transmission process, the first control parameter Pc1 is acquired or calculated for the first control target area 30a, and a data frame DF to which a first message ID (ID1) or the like is added is generated. Then, the first parameter signal Sp1 including the data frame DF is transmitted at every first period T1.

  The second task (step S12) is a second parameter signal transmission process. In the second parameter signal transmission process, a second control parameter Pc2 is acquired or calculated for the first control target area 30a, and a data frame DF to which a second message ID (ID2) or the like is added is generated. Then, the second parameter signal Sp2 including the data frame DF is transmitted every second period T2. In the present embodiment, the second period T2 is longer than the first period T1. In other words, the first period T1 is shorter than the second period T2.

  The third task (step S13) is third parameter signal transmission processing. In the third parameter signal transmission process, the third control parameter Pc3 is acquired or calculated for the first control target area 30a, and a data frame DF to which a third message ID (ID3) or the like is added is generated. Then, the third parameter signal Sp3 including the data frame DF is transmitted every third period T3. In the present embodiment, the third period T3 is longer than the second period T2. In other words, the second period T2 is shorter than the third period T3.

  The fourth task (step S14) is fourth parameter signal transmission processing. In the fourth parameter signal transmission process, when a predetermined condition is satisfied, the fourth control parameter Pc4 is acquired or calculated for the first control target area 30a, and a data frame DF to which a fourth message ID (ID4) or the like is added is generated. . Then, the fourth parameter signal Sp4 including the data frame DF is transmitted. The first to third parameter signals Sp1 to Sp3 are all periodically transmitted. On the other hand, it should be noted that the fourth parameter signal Sp4 has no periodicity.

  The fifth task (step S15) is transmission monitoring processing. In the transmission monitoring process, the transmission timing of the first and second parameter signals Sp1 and Sp2 having periodicity is monitored. In the transmission monitoring process, the transmission timing of the third parameter signal Sp3 may be monitored. Details of the transmission monitoring process will be described later with reference to FIG. Descriptions of tasks after the sixth task (step S16) will be omitted.

[A-2-3. Configuration of data frame DF]
Next, the configuration of the data frame DF used in the communication of the ECU 20 according to the present embodiment will be described. FIG. 3 is a diagram showing the configuration of the data frame DF of the present embodiment. The data frame DF is similar to that shown in FIG. 5 of WO 2013/171829.

  As shown in FIG. 3, the data frame DF includes an SOF (Start of Frame), an ID field, an RTR (Remote Transmission Request), a control field, a data field, a CRC (Cyclic Redundancy Check) sequence, and a CRC. It includes a delimiter, an acknowledgment (ACK) slot, an ACK delimiter, and an end of frame (EOF). After the data frame DF, an ITM (Intermission) is arranged.

Each field is composed of a dominant "0" and / or a recessive "1". In FIG. 3, in the field in which only the lower side (dominant) or the upper side (recessive) is indicated by a solid line, only bits indicated by a solid line can be selected. The numerical values shown below each field in FIG. 3 indicate the number of bits of each field. For example, SO F is 1 bit, ID field is 11 bits, the data field is 0 to 64 bits.

[A-2-4. Transmission monitoring process]
As described above, in the transmission monitoring process, transmission timings of the first and second parameter signals Sp1 and Sp2 having periodicity are monitored. When a plurality of periodic signals exist, the relationship of the transmission timing of each periodic signal is limited to a certain extent and falls within the normal range. If a certain ECU 20 is operated improperly from the outside, there is a high possibility that the relationship of the transmission timing of each periodic signal will not fall within the normal range. Therefore, in the transmission monitoring process of the present embodiment, the transmission monitoring unit 86 of the first ECU 20a (particularly, included in the calculation unit 52, is monitored by monitoring the transmission timing of the first and second parameter signals Sp1 and Sp2 having periodicity. It is also possible to determine the abnormality of the other parts).

  FIG. 4 is a flowchart of transmission monitoring processing in the present embodiment. In step S21, the transmission monitoring unit 86 determines whether or not there is a transmission signal (first to fourth parameter signals Sp1 to Sp4 etc.) from the first ECU 20a. The determination is performed, for example, by determining whether or not a specific part (for example, SOF) of the data frame DF appears in the wiring included in the transmission circuit 60.

  If there is no transmission signal (S21: FALSE), in step S22, the monitoring unit 86 determines whether it is time to determine whether there is an abnormality. If the determination timing has come (S22: TRUE), the process proceeds to step S27. If the determination timing has not come (S22: FALSE), the process returns to step S21. In addition, it is also possible to abbreviate | omit step S22 so that it may mention later.

  When there is a transmission signal in step S21 (S21: TRUE), in step S23, the transmission monitoring unit 86 acquires a message ID (parameter ID) of the transmission signal. In the present embodiment, the message ID is arranged in the ID field of the data frame DF.

  In step S24, the transmission monitoring unit 86 determines whether the message ID acquired in step S23 is any of the target IDs. In the present embodiment, the first control parameter signal Sp1 and the second control parameter signal Sp2 are targeted. Therefore, the monitoring unit 86 determines that the message ID acquired in step S23 is the first message ID (ID1) indicating the first control parameter signal Sp1 or the second message ID (ID2) indicating the second control parameter signal Sp2. It is determined whether or not. If the message ID acquired in step S23 is any of the target IDs (S24: TRUE), the process proceeds to step S25. If the message ID acquired in step S23 is not any of the target IDs (S24: FALSE), the process proceeds to step S26.

  In step S25, the monitoring unit 86 adds 1 to the number of transmissions Ni of the corresponding target ID. The "corresponding target ID" mentioned here means the message ID acquired in step S23. Therefore, when the message ID acquired in step S23 is the first message ID (ID1) indicating the first control parameter signal Sp1, the monitoring unit 86 adds 1 to the number of transmissions N1 of the first control parameter signal Sp1. . When the message ID acquired in step S23 is the second message ID (ID2) indicating the second control parameter signal Sp2, the monitoring unit 86 adds 1 to the number of transmissions N2 of the second control parameter signal Sp2.

  Step S26 is similar to step S22. That is, in step S26, the monitoring unit 86 determines whether it is time to determine whether there is an abnormality. If the determination timing has come (S26: TRUE), the process proceeds to step S27. If the determination timing has not come (S26: FALSE), the process returns to step S21.

  By repeating steps S21 to S26, the number of transmissions N1 of the first control parameter signal Sp1 and the number of transmissions N2 of the second control parameter signal Sp2 are counted.

  In step S27, the monitoring unit 86 calculates a ratio R1 of the number of transmissions N1 of the first control parameter signal Sp1 and the number of transmissions N2 of the second control parameter signal Sp2. In the present embodiment, the ratio R1 is defined as R1 = N1 / N2. As described later, the ratio R1 may be defined as another value.

  For example, when the first control parameter signal Sp1 is set to be transmitted three times while the second control parameter signal Sp2 is transmitted once, the ratio R1 is 3 (= 3/1) or 3 or so It becomes the value of. The reason why the time may not be three will always be because there may be a time difference between the output of the transmission signal and the processing of the monitoring unit 86.

  Note that if the ratio R1 is calculated only during a period in which the first control parameter signal Sp1 is transmitted three times and the second control parameter signal Sp2 is transmitted once, the ratio R1 will be extremely dispersed. For example, when one transmission of the first control parameter signal Sp1 is not detected, 2 (= 2/1) is obtained. Further, when one transmission of the second control parameter signal Sp2 is not detected, the number of transmissions N2 of the second control parameter signal Sp2 becomes zero, so that the ratio R1 can not be calculated. Therefore, the period for counting the number of transmissions N1 and N2 needs to have a length such that the ratio R1 converges to some extent.

  On the other hand, if the period for counting the number of transmissions N1 and N2 is too long, it takes too long to determine that an abnormality has occurred in the transmission timing of the first control parameter signal Sp1 or the second control parameter signal Sp2. It will

  Therefore, the period for counting the number of transmissions N1 and N2 for calculating the ratio R1 needs to be set in consideration of the transmission cycle T1 of the first control parameter signal Sp1 and the transmission cycle T2 of the second control parameter signal Sp2. .

  In step S28 of FIG. 4, the monitoring unit 86 determines whether the ratio R1 is within the normal range. Specifically, the monitoring unit 86 determines whether the ratio R1 is equal to or more than the lower limit threshold THr1l and equal to or less than the upper limit threshold THr1h. If the ratio R1 is within the normal range (S28: TRUE), the process proceeds to step S29. In step S29, the monitoring unit 86 determines whether an end condition for ending the transmission monitoring process is satisfied. The termination condition is, for example, that the ignition switch (not shown) is turned off.

  If the end condition is satisfied (S29: TRUE), the current transmission monitoring process is ended. If the end condition is not satisfied (S29: FALSE), in step S30, the monitoring unit 86 resets the number of transmissions N1 and N2, and then returns to step S21. In addition, as described later, when using the moving average of each of the number of transmissions N1 and N2, steps S30 (and S22 and S26) may be omitted.

  Returning to step S28, if the ratio R1 is not within the normal range (S28: FALSE), the process proceeds to step S31. In step S31, the monitoring unit 86 outputs an error. As an error output, for example, a transmission stop signal for requesting the transmission stop of the first and second parameter signals Sp1 and Sp2 can be transmitted to the first data processing unit 80a and the second data processing unit 80b. Alternatively, it is possible to transmit to the first to nth data processing units 80a to 80n transmission stop signals that request the transmission stop of all the parameter signals Sp1 to Spn. Alternatively, the monitoring unit 86 can also transmit an error display signal requesting the error display on the display unit (not shown) in the operation unit 52.

<A-3. Effects of this embodiment>
As described above, according to the present embodiment, the transmission monitoring unit 86 (abnormality detection unit) of the first ECU 20a (transmission device) transmits the parameter signal Sp in excess of the transmission frequency Ni that should be present (S28). : FALSE), the transmission of the parameter signal Sp is stopped (S31). This makes it possible to determine the abnormality of the transmission control unit 82 not on the second and third ECUs 20b and 20c (receiving device) side but on the first ECU 20a (transmitting device) side. Therefore, it becomes possible to promptly cope with the transmission abnormality in the first ECU 20a. Further, since the first ECU 20a itself detects a transmission abnormality in the first ECU 20a, it is possible to cope with only one first ECU 20a, and it is possible to suppress an increase in cost.

  In the present embodiment, the transmission monitoring unit 86 (abnormality detection unit) of the first ECU 20a (transmission device) determines that the ratio R1 (transmission number parameter) based on the transmission numbers N1 and N2 of the parameter signals Sp1 and Sp2 is out of the normal range. The transmission of the parameter signals Sp1 and Sp2 is stopped (S31 in FIG. 4) (S31). As a result, by using the ratio R1 as a parameter based on the number of transmissions N1 and N2 itself and not based on the number of transmissions N1 and N2 itself, abnormality determination according to the configuration or control of the first ECU 20a becomes possible.

  In the present embodiment, the parameter signal Sp includes a message ID (identification information) indicating the nature of the parameter signal Sp (see FIG. 2). Also, the transmission control unit 82 performs the first parameter signal Sp1 (first signal) including the first parameter ID (first identification information) in the first cycle T1 (in other words, the first predetermined number of times within a predetermined period) Send (S11 in FIG. 2). Furthermore, the transmission control unit 82 performs the second parameter signal Sp2 (second signal) including the second parameter ID (second identification information) in the second cycle T2 (in other words, the second predetermined number of times within a predetermined period). Send (S12). Furthermore, the transmission monitoring unit 86 (abnormality detection unit) transmits the first transmission number N1 that is the number of transmissions of the first parameter signal Sp1 in a predetermined period and the second transmission that is the number of transmissions of the second parameter signal Sp2 in the predetermined period. The number of times N2 is counted (S24, S25). In addition, the transmission monitoring unit 86 determines the necessity of stopping transmission of the parameter signals SpSp1 and Sp2 based on the comparison result of the first transmission number N1 and the second transmission number N2 (S28). As a result, it is possible to determine an abnormality in the signal transmission based on the comparison result of the number of transmissions N1 and N2 of the two types of parameter signals Sp1 and Sp2.

  In the present embodiment, the first period T1 is shorter than the second period T2 (in other words, the first transmission number N1 in a predetermined period is larger than the second transmission number N2). In addition, the transmission monitoring unit 86 (abnormality detection unit) determines the necessity of stopping transmission of the parameter signals Sp1 and Sp2 based on a ratio R1 of the first transmission number N1 and the second transmission number N2 in a predetermined period (see FIG. S28 of FIG. 4). As a result, even if the first parameter signal Sp1 and the second parameter signal Sp2 both have delays due to some influence, it is easy to determine whether the transmission timing is out of the normal range.

B. Modifications It is a matter of course that the present invention is not limited to the above embodiment, but can adopt various configurations based on the contents of the description of the present specification. For example, the following configuration can be adopted.

<B-1. Applicable object>
In the said embodiment, ECU20a-20c was applied to the vehicle 10 (FIG. 1). However, for example, from the viewpoint of monitoring the transmission timing of the parameter signal Sp on the side of the first ECU 20a (transmission device), the present invention is not limited thereto. For example, the ECUs 20a to 20c can also be used as moving objects such as ships and aircrafts. The ECUs 20a to 20c may be applied not only to the closed network 12 like the CAN in the vehicle 10 but also to the network 12 opened to the public like the Internet.

<B-2. Network 12 configuration>
In the above embodiment, the network 12 has three ECUs 20 a to 20 c (FIG. 1). However, for example, from the viewpoint of monitoring the transmission timing of the parameter signal Sp on the side of the first ECU 20a (transmission device), the present invention is not limited thereto. For example, if the network 12 includes at least one transmitting device (first ECU 20a) and at least one receiving device (second ECU 20b or third ECU 20c), the number of transmitting nodes and receiving nodes can be changed as appropriate. .

  In the above embodiment, the first ECU 20a which is the transmitting device, and the second ECU 20b and the third ECU 20c which is the receiving device belong to the same network 12 (FIG. 1). However, for example, from the viewpoint of monitoring the transmission timing of the parameter signal Sp on the side of the first ECU 20a (transmission device), the present invention is not limited thereto. For example, the ECUs 20 as receiving devices may belong to different networks 12 connected via the gateway 22 or the like.

<B-3. Control of First ECU 20a (Transmitting Device)>
In the above embodiment, the parameter Pc is obtained or calculated, and a data frame DF to which an ID or the like is added is generated (see FIG. 3). However, the data frame DF is selected by selecting the ID or the like of the signal Sp that generates the data frame DF, and adding the parameter Pc acquired or calculated as the one to be transmitted using the ID or the like to the ID or the like. It may be generated.

  In the above embodiment, the transmission monitoring unit 86 determines whether or not there is a transmission signal (S21 in FIG. 4) based on whether or not a specific part of the data frame DF appears in the wiring included in the transmission circuit 60. And However, since the information recorded in the storage unit 54 is transmitted by the transmission circuit 60, the above determination (S21) is performed depending on whether predetermined information (for example, a predetermined data frame DF) is stored in the storage unit 54. You may do it.

  In the above embodiment, whether the transmission timing of the parameter signal Sp deviates from the normal range is determined using a ratio R1 of the transmission number N1 of the first parameter signal Sp1 and the transmission number N2 of the second parameter signal Sp2 (FIG. S28 of 4). However, whether or not the transmission timing of the parameter signal Sp is out of the normal range may be determined by another method.

  For example, it may be determined whether or not the first number of transmissions N1 or the second number of transmissions N2 is within the normal range during a predetermined time (for example, any of several hundreds of milliseconds to several tens of seconds). Alternatively, it may be determined whether the transmission cycle T1 of the first parameter signal Sp1 or the transmission cycle T2 of the second parameter signal Sp2 is within the normal range. Alternatively, it is also possible to determine whether the time interval between the first parameter signal Sp1 and the second parameter signal Sp2 transmitted immediately thereafter is within the normal range.

  In the above embodiment, a ratio R1 (= N1 / N2), which is a value obtained by dividing the number of transmissions N1 of the first parameter signal Sp1 by the number of transmissions N2 of the second parameter signal Sp2, is used (S27, S28 in FIG. 4). However, for example, from the viewpoint of monitoring the transmission timing of the parameter signal Sp on the side of the first ECU 20a (transmission device), the present invention is not limited thereto. A value obtained by dividing the second number of transmissions N2 by the first number of transmissions N1 may be taken as a ratio R1 (= N2 / N1).

  In the above embodiment, it is determined whether or not the ratio R1 is within the normal range by using both the lower threshold THr1l and the upper threshold THr1h (S28 in FIG. 4). However, for example, from the viewpoint of monitoring the transmission timing of the parameter signal Sp on the side of the first ECU 20a (transmission device), the present invention is not limited thereto. For example, the ratio R1 may be compared with only one of the lower threshold THr11 or the upper threshold THr1h. In other words, only one of the case where the first transmission number N1 is too large and the case where it is too small may be monitored.

  In the above embodiment, the number of transmissions N1 and N2 is reset each time it is determined whether or not the ratio R1 is within the normal range (S30 in FIG. 4). However, for example, from the viewpoint of monitoring the transmission timing of the parameter signal Sp on the side of the first ECU 20a (transmission device), the present invention is not limited thereto. For example, instead of resetting the number of transmissions N1 and S2, it is also possible to use a moving average of each of the number of transmissions N1 and S2. In that case, steps S22 and S26 of FIG. 4 may be omitted.

<B-4. Other>
In the above-described embodiment, there are cases where the comparison of numerical values includes and does not include the equal sign (S28 in FIG. 4 and the like). However, for example, unless there is a special meaning including or excluding the equal sign (in other words, when the effects of the present invention can be obtained), it is optional whether the equal sign is included or not included in the comparison of numerical values. It can be set to

  In that sense, for example, it is determined whether or not the ratio R1 in step S28 of FIG. 4 is the lower threshold THr1l or more (THr11 ≦ R1), and it is determined whether the ratio R1 is greater than the lower threshold THr11 (THr11 <R1 Can be replaced by).

12 ... Communication network 20a ... 1st ECU (transmission device)
82: Transmission control unit 86: Transmission monitoring unit (abnormality detection unit)
N1 ... first transmission number N2 ... second transmission number Pc ... control parameter Pc1 ... first control parameter Pc2 ... second control parameter R1 ... ratio (parameter based on transmission number)
Sp: Parameter signal Sp1: First parameter signal Sp2: Second parameter signal T1: First period T2: Second period

Claims (2)

A transmission control unit that transmits a signal to the communication network a predetermined number of times within a predetermined period;
An abnormality detection unit that stops transmission of the signal by the transmission control unit when the number of transmissions of the signal by the transmission control unit exceeds the predetermined number within the predetermined period;
Equipped with
The signal includes identification information indicating the nature of the signal,
The transmission control unit
Transmitting a first signal including first identification information a first predetermined number of times within the predetermined period;
Transmitting a second signal including second identification information a second predetermined number of times within the predetermined period;
The abnormality detection unit
The first number of transmissions, which is the number of transmissions of the first signal in the predetermined period, and the second number of transmissions, which is the number of transmissions of the second signal in the predetermined period, are counted.
It is determined whether it is necessary to stop transmission of the first signal and the second signal based on the comparison result of the first number of transmissions and the second number of transmissions. In the transmitter according to claim 1 ,
The first number of transmissions is greater than the number of second transmissions,
The abnormality detection unit determines the necessity of stopping the transmission of the first signal and the second signal based on a ratio of the first number of transmissions and the second number of transmissions in the predetermined period. Sending device.

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