Communication system

Abstract

A communication system is provided with: a domain controller (10) connected to a bus (10a) in a global area (100) and a bus (10b) in a local area (201); an ECU (domain controller (20), etc.) belonging to the global region (100); and ECUs (ECUs (11, 12), etc.) belonging to the local area (201). A domain controller (10) receives, from a bus (10a), a data frame (31) including a CAN ID (ID: 100) and control information (A, B) processed by an ECU (12), generates a data frame (34) including a CAN ID (ID: 300) different from the CAN ID (ID: 100), the control information (A, B), and the control information (P), and transmits the data frame (34) through a bus (10b).

Description

Technical Field

[0001] This invention relates to a communication system for sending and receiving data frames via a communication network. Background Technology

[0002] As a message processing technology for relaying messages between electronic control units, a vehicle network system such as Patent Document 1 is known. In this vehicle network system, the gateway has: a receiving unit that sequentially receives first frames from the bus of a CAN network; a determining unit that determines, for the first frames received by the receiving unit, whether the data of the first frame should be sent to the Ethernet network; and a sending unit that sends second frames containing the data of each of the multiple first frames determined by the determining unit to be sent to the Ethernet network to the Ethernet network.

[0003] Patent Document 1: International Publication No. 2017 / 203902 Summary of the Invention

[0004] With the increasing complexity of electronic control systems, the number of frame IDs transmitted and received between electronic control units (ECUs) has increased. In the vehicle network system described in Patent Document 1, there is a problem that the first type of frame is transmitted and received through the CAN network, but there is an upper limit to the number of frame IDs in CAN, resulting in an insufficient number of usable frame IDs within the network.

[0005] The problem this invention aims to solve is to provide a communication system that can increase the number of usable frame IDs.

[0006] The present invention relates to a communication system that solves the above-mentioned problems by having the following structure: a domain controller connected to a first bus and a second bus; a first ECU belonging to a first network area; and a second ECU belonging to a second network area. The domain controller receives a first data frame containing a first frame ID and first control information from the first bus, generates a second data frame containing a second frame ID different from the first frame ID, the first control information, and the second control information, and transmits the second data frame through the second bus.

[0007] The effects of the invention

[0008] According to the present invention, the number of usable frame IDs can be increased. Attached Figure Description

[0009] Figure 1 This is a structural diagram of a communication system according to an embodiment of the present invention.

[0010] Figure 2 It means Figure 1 A block diagram of the ECU structure.

[0011] Figure 3 It means in Figure 1 A diagram illustrating the data structure of communication data frames in an in-vehicle network system.

[0012] Figure 4 This is a structural diagram of a communication system according to another embodiment of the present invention.

[0013] Figure 5 This is a structural diagram of a communication system according to other embodiments of the present invention. Detailed Implementation

[0014] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

[0015] In this embodiment, an example of applying the communication system of the present invention to an in-vehicle network system will be used for illustration. For example... Figure 1 As shown, the communication system involved in this embodiment includes a gateway 1, domain controllers (DM) 10 and 20, and battery control units (ECU) 11 and 12. The gateway 1, domain controllers 10 and 20, and battery control units (ECU) 11 and 12 are connected via CAN.

[0016] The communication network of the communication system involved in this embodiment includes a global area 100 and local areas 201 and 202. The global area 100 is a relay area for sending and receiving data frames between multiple local areas 201 and 202, and is located at a higher level relative to the multiple local areas 201 and 202. Local areas 201 and 202 are areas corresponding to the functional domains of the vehicle. The functional domains of the vehicle are categorized by grouping functions such as the powertrain or autonomous driving system. These domains constitute multiple control groups divided based on the basic structure of the vehicle.

[0017] A domain consists of ECUs and buses. Examples of domains include the multimedia domain, the ADAS (Advanced Driver-Assistance System) domain, and the powertrain domain. ECUs in the multimedia domain control information display devices such as the head unit, including the in-vehicle navigation system. ECUs in the ADAS domain control in-vehicle equipment related to driver assistance control, such as cameras, radar, LIDAR (Light Detection and Ranging), and object recognition devices that perform sensor fusion processing based on their outputs. ECUs in the powertrain domain control the vehicle's drive sources, such as the engine and electric motor.

[0018] ECUs belonging to the same domain can send and receive data frames within a single local area. On the other hand, when ECUs belonging to one domain send and receive data frames with ECUs belonging to other domains, the data frames are sent and received via gateway 1 and domain controllers 10 and 20 belonging to global area 100.

[0019] Additionally, each local region 201, 202 is allocated at least one domain controller 10, 20. For example, domain controller 10 is allocated to local region 201, and domain controller 20 is allocated to local region 202. A gateway 1 is allocated to the global region 100 for transmitting data frames between multiple local regions 201, 202. That is, the communication network uses gateway 1 as a vertices to connect the CAN communication network in a tree-like manner, and domain controllers 10, 20 function as hubs in the communication network. Furthermore, the global region 100, local regions 201, and local regions 202 are each composed of closed communication networks. Gateway 1, domain controllers 10, 20 are connected to a pair of buses. Moreover, when a pair of buses belong to different regions, the ECU connected to the pair of buses can divide the network regions. On the other hand, as... Figure 1 As shown, ECUs 11 and 12 are connected to the CAN communication network via a single bus, therefore, the network area is not divided.

[0020] Gateway 1 is an ECU that is connected to multiple domain controllers 10 and 20 via multiple buses and performs data frame relay processing between the buses. If Gateway 1 receives data frames from domain controllers 10 and 20 and buffers them, it will send the data frames to the target ECU (domain controller 10 or 20) sequentially or according to the transmission order based on the frame ID.

[0021] Domain controllers 10 and 20 integrate multiple ECUs belonging to the network area and are configured to correspond to the functional domains of the vehicle. Domain controllers 10 and 20 are ECUs that perform relay processing of data frames within local areas 201 and 202 and relay processing of data frames between global area 100 and local areas 201 and 202. For example, domain controller 10 integrates multiple ECUs 11 and 12 belonging to local area 201 and is configured in the vehicle corresponding to the vehicle domain.

[0022] Domain controller 10 is located in local area 201, and domain controller 20 is located in local area 202. Domain controller 10 is connected to bus 10a in global area 100 and to bus 10b in local area 201. Domain controller 10 transmits data frames between ECUs 11 and 12 belonging to local area 201. When sending data frames from ECUs 11 and 12 belonging to local area 201 to ECUs belonging to other local areas, domain controller 10 receives data frames from bus 10b and sends data frames from bus 10a to global area 100. Conversely, when sending data frames from ECUs belonging to other local areas to ECUs 11 and 12 belonging to local area 201, domain controller 10 receives data frames from bus 10a and sends data frames from bus 10b to local area 201.

[0023] Domain controller 20 is connected to bus 10 within global region 100 and to bus within local region 202. Like domain controller 10, domain controller 20 transmits and receives data frames for ECUs belonging to local region 202.

[0024] ECUs 11 and 12 belong to local area 201. ECUs 11 and 12 are composed of computers with hardware and software. Although details are not shown, ECU 4 has a ROM (Read Only Memory) for storing programs, a CPU (Central Processing Unit) for executing programs stored in the ROM, and RAM (Random Access Memory) for temporarily storing data generated during program execution. The ROM stores control programs for controlling the on-board devices connected to each ECU 11 and 12. In addition, ECUs such as gateway 1 and domain controllers 10 and 20 may also have the same structure as ECUs 11 and 12.

[0025] Gateway 1 and domain controllers 10 and 20 are ECUs belonging to global zone 100. Domain controller 10 and ECUs 11 and 12 are ECUs belonging to local zone 201. Domain controller 20 is an ECU belonging to local zone 202. Furthermore, the ECUs belonging to each zone are not limited to... Figure 1 The ECU shown.

[0026] Next, refer to Figure 2 The structure of the ECU, such as the domain controller 10, will be described. The domain controller 10 has a communication unit 101, a data acquisition unit 102, a frame generation unit 103, and a storage unit 104 as functional modules.

[0027] The communication unit 101 communicates with ECUs belonging to the same network area via CAN. Additionally, the communication unit 101 communicates with other ECUs via CAN and gateway 1. When receiving data frames from other ECUs, the communication unit 101 acknowledges the CAN ID of the data frame and receives the data frame with the predetermined CAN ID.

[0028] The data acquisition unit 102 acquires sensor information representing the detection results obtained by the sensors from on-board devices such as sensors connected to the ECU. The frame generation unit 103 generates control information containing the sensor information based on the sensor information acquired by the data acquisition unit 102. When control commands are output to the on-board device via other ECUs, the frame generation unit 103 generates control information containing the control commands. The control information is information processed by the ECU. For example, if the control information includes vehicle speed information, the control information is processed by an ECU for controlling the powertrain or an ECU for controlling the autonomous driving system. Furthermore, the control information is not limited to being processed by the ECU of the data frame's destination, but can also be processed by the ECU of the sending source. The frame generation unit 103 generates a data frame to be transmitted by the communication unit 101 based on the generated control information. Specifically, the frame generation unit 103 sets a CAN ID according to the type of sensor information acquired by the data acquisition unit 10. The frame generation unit 103, for example, stores a table that associates sensor information with CAN IDs, and sets the CAN ID based on this table.

[0029] Figure 3 An example of the structure of a data frame generated by the frame generation unit 103 is shown. The data frame has an ID field 91 for storing the CAN ID and a data field 92 for storing data. Control information processed by the ECU is stored in the data field 92. Figure 3 In the example, "100" is assigned as the CAN ID, and "A", "B", and "C" are stored as the type of control information. Furthermore, data frames are not limited to containing CAN ID and control information; they may also include DLC (Date Length Code), etc.

[0030] The storage unit 104 stores the data stored in the data frames received by the communication unit 101.

[0031] In this embodiment, the communication protocol in global region 100 and local regions 201 and 202 is the CAN protocol. No identifier representing the source or destination is assigned to data frames used for communication based on the CAN protocol. Each ECU assigns a CAN ID to each data frame before sending it, and the receiving ECU determines the data frame to be received based on the CAN ID. The number of CAN IDs is capped, for example, at 2048. Therefore, when the entire communication system, including global region 100 and local regions 201 and 202, is treated as a single communication region and assigned a CAN ID, the number of usable frame IDs for a data frame cannot exceed the maximum number of CAN IDs. That is, the number of usable frame IDs cannot be increased.

[0032] In this embodiment, to increase the number of usable frame IDs, frame IDs are managed separately for each network connected to domain controllers 10 and 20. Hereinafter, refer to... Figure 1 The frame ID management method in this embodiment will be explained. Furthermore, in Figure 1 In the diagram, data frame 31 is named "DM20_A101" and data frame 32 is named "ECU11_A201". Filenames are shown for clarity and to distinguish between frames, but the filename information is not entered into the data frame.

[0033] exist Figure 1 In this example, domain controller 20 sends data frame 31. Data frame 31 contains a CAN ID (ID: 100) and control information (A, B, C). Data frame 31 is used for communication within global region 100, and its destination is DM 10. At least one of the three types of control information (A), (B), and (C) is processed by an ECU belonging to global region 100.

[0034] Within the global area 100, CAN IDs are managed such that the ECUs corresponding to the transmission targets of CAN IDs (ID: 100) include DM 10. Therefore, the frame generation unit included in the domain controller 20 assigns the CAN ID (ID: 100) to the data frame 31, ensuring that the ECUs corresponding to the transmission targets of control information (A, B, C) include the domain controller 10. Furthermore, the domain controller 20 transmits the data frame 31 to the CAN communication network within the global area 100.

[0035] Additionally, ECU 11 sends data frame 32. Data frame 32 contains a CAN ID (ID: 100) and control information (X, Y). Data frame 32 is used for communication within local areas 201 and 2, and its destination is DM 10. Control information of any one of the three types of control information (X) and (Y) is processed by an ECU (e.g., ECU 12) belonging to local area 200.

[0036] Within local area 201, CAN ID is managed such that the ECU corresponding to the transmission target of CAN ID (ID: 100) includes DM 10. Therefore, the frame generation unit included in ECU 11 assigns CAN ID (ID: 100) to data frame 31, so that the ECU receiving control information (X, Y) includes domain controller 10. Furthermore, ECU 11 transmits data frame 32 to the CAN communication network within local area 201.

[0037] Here, the frame ID contained in data frame 31 and the frame ID contained in data frame 32 are the same ID (ID: 100). Conventionally, when the CAN ID is managed as a single communication area, encompassing the global area 100 and local areas 201 and 202, the same frame ID is not assigned to data frames communicating between one set of multiple ECUs and data frames communicating between another set of multiple ECUs within that single communication area. However, in this embodiment, the network in the communication system is divided by domain controllers 10 and 20, and frame IDs are managed on a per-region basis. Therefore, it is possible to assign the same frame ID to data frames communicating within the global area 100 and data frames communicating within the local area 201.

[0038] In cases where data frames 31 and 32 are assigned the same CAN ID across different communication regions, the frame ID of data frame 31 is assigned when multiple ECUs (domain controllers 10 and 20) belonging to global region 100 become both the source and the destination of transmission. Similarly, the frame ID of data frame 32 is assigned when multiple ECUs (domain controllers 10 and ECU 11) belonging to local region 201 become both the source and the destination of transmission.

[0039] Domain controller 10, which serves as the receiving targets 31 and 32 of data frames, is connected to buses 10a and 10b. Domain controller 10 receives data frame 31 sent from domain controller 20 via bus 10a. Additionally, domain controller 10 receives data frame 32 sent from ECU 11 via bus 10b. Bus 10a is a CAN communication network within global area 100; therefore, it can be determined that data frame 31 received from bus 10a is a data frame used for communication within global area 100. Similarly, it can be determined that data frame 32 received from bus 10b is a data frame used for communication within local area 201. Furthermore, domain controller 20 can determine the transmission target of a data frame based on a pre-determined transmission target corresponding to the frame ID. The frame ID (ID: 100) of data frame 31 used for communication within global area 100 determines, at the communication management level, that the ECU used for transmission is domain controller 20. Furthermore, the frame ID (ID: 100) of data frame 32 communicated within local area 201 determines the target ECU as ECU 11 at the communication management level. Therefore, domain controller 10 can determine the target ECU based on the data frame 31 received from bus 10a and the CAN ID assigned to data frame 31.

[0040] As described above, the communication system according to this embodiment includes: a domain controller 10 connected to bus 10a in global region 100 and bus 10b in local region 201; an ECU (domain controller 20, etc.) belonging to global region 100; and an ECU (ECU 11, 12, etc.) belonging to local region 201. Data frame 31 contains a CAN ID (ID: 100) and control processing (control information processed by domain controller 20, etc.), and data frame 32 contains a CAN ID (ID: 100) and control processing (control information processed by ECU 11). The CAN ID of data frame 31 and the CAN ID of data frame 32 are the same. This increases the number of usable frame IDs.

[0041] Furthermore, global region 100 corresponds to the "first network region" of this invention, local regions 201 and 202 correspond to the "first network region" of this invention, ECUs belonging to global region 100 (domain controller 20, etc.) correspond to the first ECU, and ECUs belonging to local regions 201 and 202 (ECU 11, 12, etc.) correspond to the second ECU. Additionally, CAN ID corresponds to the "frame ID" of this invention. Furthermore, control information (A, B, C) corresponds to the "first control information" of this invention, control information (X, Y) corresponds to the "second control information" of this invention, and CAN ID (ID: 100) corresponds to the "first and second frame IDs" of this invention.

[0042] Second Implementation Method

[0043] Next, the communication system according to the second embodiment will be described. The difference between the communication system according to the second embodiment and the communication system according to the first embodiment is that control for changing the frame ID (CAN ID) is added in the domain controllers 10 and 20. Other than this, the control is the same as in the first embodiment, and the above description is used for the same structure and control as in the first embodiment.

[0044] Figure 4 This is a block diagram of the communication system involved in this embodiment. Figure 4 In the communication system shown, the gateway 1 and other ECUs, network area and CAN communication network are the same as in the first embodiment.

[0045] exist Figure 4 In this example, domain controller 10 receives data frame 31 from domain controller 20. The control information (A, B, C) stored in data frame 31 is information processed by ECU 12. Alternatively, the control information (A, B, C) can also be information processed by other ECUs, such as domain controller 10 and ECU 12. The CAN ID (ID: 101) assigned to data frame 31 is the same as the CAN ID of data frame 32. That is, the CAN ID (ID: 101) of data frame 31 is the same as the frame ID used within local area 201. If the CAN ID is not changed, and domain controller 10 sends the data frame containing control information (A, B, C) to local area 201, a communication conflict will occur between data frame 31 and data frame 32.

[0046] To avoid such communication conflicts, domain controller 10 changes the CAN ID contained in data frame 31 from (ID: 100) to (ID: 200). That is, domain controller 10 assigns a CAN ID different from the CAN ID (ID: 100) to data frame 31. The CAN ID (ID: 200) is an ID used within local area 201 and is used when sending data frames from domain controller 10 to ECU 12. Domain controller 10 then sends data frame 33, containing the changed CAN ID (ID: 200) and control information (A, B, C), to local area 201 via bus 10b.

[0047] Thus, in this embodiment, when data frames with the same data structure in data field 92 are sent across different communication areas (for example, when sent from global area 100 to local areas 201, 202), the CAN ID is changed.

[0048] As described above, in the communication system of this embodiment, the domain controller 10 receives a data frame 31 containing a CAN ID (ID: 100) and control information processed by the ECU 12 from the bus 10a, assigns a CAN ID (ID: 200) different from the CAN ID (ID: 100) to the data frame 33, and transmits the data frame 33 through the bus 10b. This increases the number of usable frame IDs.

[0049] Furthermore, in the communication system according to this embodiment, if the CAN ID (ID: 100) is the same as the usage frame ID used in the local area, the domain controller 10 changes the CAN ID (ID: 100) to the CAN ID (ID: 200) and sends the data frame 33. This increases the number of usable frame IDs.

[0050] Furthermore, the ECUs (ECU 11, 12, etc.) belonging to local areas 201 and 202 are equivalent to the "third ECU" of this invention, data frames 31 and 33 are equivalent to the "third frame" of this invention, control information (A, B, C) are equivalent to the "third control information" of this invention, CAN ID (ID: 100) is equivalent to the "first frame ID" of this invention, and CAN ID (ID: 200) is equivalent to the "third frame ID" of this invention.

[0051] Third Implementation Method

[0052] Next, the communication system according to the third embodiment will be described. The communication system according to the third embodiment differs from the communication system according to the second embodiment in that new control information is added to the domain controllers 10 and 20 to send data frames. Other than this, the control is the same as in the second embodiment; the above description refers to the same structure and control as in the second embodiment.

[0053] Figure 5 This is a block diagram of the communication system involved in this embodiment. Figure 5 In the communication system shown, global area 100 includes domain controllers 10 and 20, as well as domain controller 30. Domain controller 20 and ECU 21 belong to local area 202.

[0054] exist Figure 5In this example, domain controller 10 receives data frame 31 from domain controller 20. The control information (A, B) stored in data frame 31 is information processed by ECU 12. On the other hand, the control information (C) stored in data frame 31 is control information not processed by ECUs 11, 12 belonging to local area 201, but by other ECUs not belonging to local area 201. The CAN ID (ID: 100) of data frame 31 is used by data frame 32 and is duplicated with the frame ID used within local area 201. Therefore, domain controller 10 changes the CAN ID contained in data frame 31 from (ID: 100) to (ID: 300).

[0055] Furthermore, control information (C) is information that is not processed by the ECU within local area 201, and may not be sent to local area 201. Therefore, domain controller 10 stores control information (P) in the location where control information (C) is stored in the data field. Control information (P) is information processed by ECU 12. Additionally, domain controller 10 sends data frame 33 containing the modified CAN ID (ID: 300) and control information (A, B, P) to local area 201 via bus 10b.

[0056] As another example of data frame communication, domain controller 20 receives data frame 35 from domain controller 30. The control information (A) stored in data frame 35 is information to be processed by ECU 21. Additionally, empty data is stored in the data field of data frame 35, becoming a portion of the unused capacity. The CAN ID (ID: 200) of data frame 35 is the same as the frame ID used within local area 202. Therefore, domain controller 10 changes the CAN ID contained in data frame 31 from (ID: 200) to (ID: 400).

[0057] Domain controller 10 stores the control information (Q) in a location in the data field where empty data is stored. The control information (Q) is information processed by ECU 21. Furthermore, domain controller 20 sends data frame 36 containing the modified CAN ID (ID: 400) and control information (A, Q) to local area 202.

[0058] Thus, in this embodiment, when data frames with the same data structure in data field 92 are sent across different communication areas (for example, when sending from global area 100 to local area 200), only the required information (signals) is extracted and sent as another data frame.

[0059] As described above, this embodiment includes: a domain controller 10 connected to bus 10a in global region 100 and bus 10b in local region 201; an ECU (domain controller 20, etc.) belonging to global region 100; and an ECU (ECU 11, 12, etc.) belonging to local region 201. Domain controller 10 receives a data frame 31 from bus 10a containing a CAN ID (ID: 100) and control information (A, B) processed by ECU 12, generates a data frame 34 containing a CAN ID (ID: 300) different from the CAN ID (ID: 100), control information (A, B), and control information (P), and transmits data frame 34 via bus 10b. This increases the number of usable frame IDs.

[0060] Furthermore, in this embodiment, when the data frame 31 contains control information (C) processed by an ECU other than ECUs 11 and 12, the domain controller 10 changes the control information (C) to control information (P) and generates the data frame 34. This increases the number of usable frame IDs.

[0061] In addition, in this embodiment, if the CAN ID (ID: 100) is the same as the usage frame ID used in the local area 201, the domain controller 10 changes the CAN ID (ID: 100) to the CAN ID (ID: 300) and generates a data frame 34. This increases the number of usable frame IDs.

[0062] Furthermore, the ECUs (ECU 11, 12, etc.) belonging to local areas 201 and 202 are equivalent to the second ECU, data frames 31 and 35 are equivalent to the "first data frame" of this invention, control information (A, B) are equivalent to the "first control information" of this invention, CAN ID (ID: 100) is equivalent to the "first frame ID" of this invention, CAN ID (ID: 300, 400) is equivalent to the "second frame ID" of this invention, control information (P, Q) is equivalent to the "second control information" of this invention, control information (C) is equivalent to the "third control information" of this invention, and data frames 34 and 36 are equivalent to the "second data frame" of this invention.

[0063] Explanation of the label

[0064] 1 Gateway

[0065] 10a and 10b buses

[0066] 10, 20, 30 Domain Controllers (DM)

[0067] 11, 12, 21 ECU

[0068] Data frames 31-35

[0069] 100 Global Region

[0070] 201, 202 Local Area

Claims

1. A communication system for transmitting and receiving data in a communication network comprising a first network area and a second network area. This communication system has the following features: A domain controller, which is connected to a first bus in the first network area and a second bus in the second network area; The first ECU belongs to the first network region; as well as The second ECU, which belongs to the second network region. The domain controller receives a first data frame from the first bus, which includes a first frame ID and first control information processed by the second ECU. The domain controller generates a second data frame containing a second frame ID different from the first frame ID, the first control information, and second control information processed by the second ECU. The domain controller sends the second data frame via the second bus.

2. The communication system according to claim 1, wherein, If the domain controller contains third control information processed by an ECU other than the second ECU in the first data frame, it changes the third control information to the second control information and generates the second data frame.

3. The communication system according to claim 1 or 2, wherein, If the first frame ID is the same as the usage frame ID used in the second network area, the domain controller changes the first frame ID to the second frame ID and generates the second data frame.

4. The communication system according to any one of claims 1 to 3, wherein, The domain controller integrates multiple ECUs belonging to the second network region and is configured in the vehicle in accordance with the functional domains of the vehicle.

5. The communication system according to any one of claims 1 to 4, wherein, When multiple ECUs belonging to the first network region become both the source and the destination of transmission, the first frame ID is assigned. When multiple ECUs belonging to the second network region become both the source and the destination of transmission, the second frame ID is assigned.

6. The communication system according to any one of claims 1 to 5, wherein, The frame ID assigned to a data frame communicating within the first network area or the second network area does not contain information about the sending target. The domain controller determines the transmission target of the data frame based on a pre-determined transmission target corresponding to the frame ID.

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