Log management device and vehicle system

Abstract

According to the present invention, a log management device for managing log recording by a plurality of in-vehicle devices comprises a log management device communication unit for receiving management information on available capacity for recording a log from any of the in-vehicle devices, and a proxy recording destination determination unit for determining, on the basis of the management information received by the log management device communication unit, an in-vehicle device for recording a log in place of the in-vehicle device that transmitted the management information, wherein the log management device communication unit transmits a command, to the in-vehicle device that transmitted the management information, requesting log transmission to the in-vehicle device determined by the proxy recording destination determination unit.

Description

Log management device and vehicle system

[0001] The present disclosure relates to a log management device and a vehicle system.

[0002] Modern automobiles are equipped with multiple and varied ECUs (Electronic Control Units). With the spread of connected cars and advances in technologies such as autonomous driving, the types and size of log data collected from each control ECU are expected to increase, making data collection and data recording functions increasingly important. Regarding the data collection function, Patent Literature 1 discloses that a server device, which has more memory resources and processing power than an in-vehicle device, collects and analyzes logs from the in-vehicle device.

[0003] JP 2019-175017 A

[0004] However, ECUs constituting a vehicle do not have abundant memory resources. Therefore, when there is little free space for recording logs and an event that requires recording a log occurs, the ECU must discard already recorded logs or discard newly acquired logs, resulting in the loss of log data used for analysis. Therefore, it is desirable to increase the amount of logs that can be recorded in on-board devices such as ECUs.

[0005] One aspect of the present disclosure is a log management device that manages the recording of logs by multiple on-board devices, and includes a log management device communication unit that receives management information regarding available capacity for recording logs from one of the on-board devices, and a proxy recording destination determination unit that determines an on-board device that will record logs instead of the on-board device that sent the management information based on the management information received by the log management device communication unit, and the log management device communication unit sends a command to the on-board device that sent the management information requesting that the log be sent to the on-board device determined by the proxy recording destination determination unit.

[0006] According to one aspect of the present disclosure, the number of logs that can be recorded in an in-vehicle device can be increased.

[0007] 10 is a diagram showing the configuration of a vehicle system according to a first embodiment. A sequence diagram showing the processing of the vehicle system according to the first embodiment. A table showing a free space management table according to the first embodiment. A flowchart showing the processing when an event occurs according to the first embodiment. A flowchart showing the processing of determining an in-vehicle device as a proxy recording destination according to the first embodiment. A table showing the free space management table of FIG. 3 with a proxy recording enable flag added. A table showing a log recording destination management table according to the first embodiment. A sequence diagram showing the processing of a vehicle system according to a second embodiment. A table showing the free space management table of the second embodiment. A flowchart showing the processing of determining an in-vehicle device to send a log transmission request according to the second embodiment. A table showing the free space management table of FIG. 9 with the log transmission target flag changed. A flowchart showing the processing of sending a log transmission request according to the second embodiment. A flowchart showing the processing of sending a log according to the second embodiment. A flowchart showing the processing of recording a log according to the second embodiment. A table showing the log recording management table according to the second embodiment. A sequence diagram showing the processing of a vehicle system according to a third embodiment. A flowchart showing the processing when an event occurs according to the third embodiment. A flowchart showing the processing when insufficient capacity information and a proxy recording destination search request according to the third embodiment are received. A flowchart showing the processing when a proxy recording permission response request according to the third embodiment is received. 13 is a flowchart showing a process when a proxy recordable response is received according to the third embodiment.

[0008] Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that components with the same reference numerals in each embodiment have the same functions in each embodiment unless otherwise specified, and description thereof will be omitted.

[0009] [First Embodiment] Fig. 1 is a diagram showing the configuration of a vehicle system 1 according to a first embodiment. As shown in Fig. 1, the vehicle system 1 according to this embodiment includes multiple on-board devices 10, 11, 12, and 13 connected to one another via a communication bus 50. The on-board device 10 functions as a master ECU and an integrated ECU that manages the on-board devices 11, 12, and 13. The on-board devices 11, 12, and 13 function as slave ECUs managed by a log collection device 4. Although Fig. 1 shows only the on-board devices 11, 12, and 13, the vehicle system 1 also includes multiple other on-board devices that function as similar ECUs.

[0010] The in-vehicle devices 11, 12, and 13 are, for example, any of the ECUs for the powertrain, chassis, body, multimedia, and ADAS systems in the vehicle system 1. The powertrain ECUs are, for example, the engine ECU, transmission ECU, and hybrid ECU. The chassis ECUs are, for example, the power steering ECU, brake ECU, and accelerator ECU.

[0011] Body-related ECUs include, for example, ECUs for wipers, automatic doors, power windows, keyless entry, power door mirrors, interior lighting, headlights, tire pressure monitoring systems, immobilizers (anti-theft devices), etc. Multimedia-related ECUs include, for example, ECUs for navigation systems, ETCs (Electronic Toll Collection Systems), audio systems, and backup monitors.

[0012] Examples of ADAS (Advanced Driver Assistance Systems) ECUs include a driving assistance ECU, a stereo camera ECU, a surrounding monitoring ECU, a locator ECU, and an autonomous driving ECU.

[0013] The in-vehicle device 10, which is a master ECU, is equipped with a log management device 100. The log management device 100 manages the recording of logs by the multiple in-vehicle devices 11, 12, and 13, which are slave ECUs. The logs are information recorded about the operating status of the in-vehicle devices 11, 12, and 13. The logs are information in which the startup, shutdown, data transmission and reception, errors, failures, and communication history with the outside of the in-vehicle devices 11, 12, and 13 are recorded in chronological order. Note that, in this embodiment, the log management device 100 is provided inside the in-vehicle device 10, but the log management device 100 may also be provided outside the in-vehicle devices 10, 11, 12, and 13.

[0014] The on-board device 10 equipped with the log management device 100 and the on-board devices 11, 12, and 13 are computers equipped with a CPU (Central Processing Unit) and memory. The memory includes a main storage device and an auxiliary storage device. The main storage device is used as a working area for the CPU, a storage area for computer programs, a storage area for data, and a buffer area for communication data. The main storage device is formed, for example, by a combination of RAM (Random Access Memory) and ROM (Read Only Memory). Computer programs such as an operating system and firmware are installed in the memory. The auxiliary storage device is, for example, a solid state drive (SSD) and a hard disk drive (HDD).

[0015] The CPU is not limited to a single processor and may have a multi-processor configuration. Furthermore, a single CPU connected via a single socket may have a multi-core configuration. At least some of the processing of each unit described below may be performed by a processor other than the CPU, such as a dedicated processor such as a DSP (Digital Signal Processor), a GPU (Graphics Processing Unit), a numerical calculation processor, a vector processor, or an image processing processor. Furthermore, the CPU may be configured with an integrated circuit (IC) and other digital circuits, or may be partially configured with analog circuits.

[0016] The integrated circuit includes an LSI, an ASIC (Application Specific Integrated Circuit), and a PLD (Programmable Logic Device). The PLD includes, for example, an FPGA (Field-Programmable Gate Array). The CPU may be a combination of a processor and an integrated circuit. Examples of the combination of a processor and an integrated circuit include an MCU (Micro Controller Unit), an SoC (System-on-a-chip), a system LSI, and a chipset. The CPU loads a computer program stored in memory into a main storage device and executes the processing described in the program, thereby executing the processing of each part of the log management device 100 and the in-vehicle devices 10, 11, 12, and 13 described below.

[0017] The log management device 100 includes a log management device communication unit 101, a proxy recording destination determination unit 102, a management information recording unit 103, and an information management unit 104. The log management device communication unit 101 receives management information related to the available capacity for recording logs from one of the in-vehicle devices 11, 12, and 13. The log management device communication unit 101 also transmits, for example, a command to the in-vehicle device 12 that transmitted the management information, requesting that the log be sent to the in-vehicle device 11 determined by the proxy recording destination determination unit 102. Note that hereinafter, the command requesting that the log be sent to the in-vehicle device 11 determined by the proxy recording destination determination unit 102 may be referred to as a log transmission request.

[0018] The proxy recording destination determination unit 102 determines, for example, the in-vehicle device 11 that will record the log instead of the in-vehicle device 12 that transmitted the management information, based on the management information received by the log management device communication unit 101. The management information recording unit 103 records the management information for each of the in-vehicle devices 10, 11, 12, and 13. The information management unit 104 manages the management information recorded in the management information recording unit 103.

[0019] The in-vehicle device 10, excluding the log management device 100, and the in-vehicle devices 11, 12, and 13 each include a log recording unit 111, a log recording control unit 112, a capacity determination unit 113, and an in-vehicle device communication unit 114. The log recording unit 111 records a log. The log recording control unit 112 records a log in the log recording unit 111 in response to the occurrence of an event that requires log recording. The capacity determination unit 113 determines whether the free space in the log recording unit 111 is insufficient. The in-vehicle device communication unit 114 transmits management information to the log management device 100, and transmits logs to, for example, other in-vehicle devices 11. Note that the in-vehicle devices 10, 11, 12, and 13 may have a configuration other than that shown in FIG. 1 .

[0020] The communication bus 50 is physically a plurality of communication buses, and the standards of the communication bus 50 include CAN (registered trademark), LIN (registered trademark), FlexRay (registered trademark), Ethernet (registered trademark), and the like.

[0021] The operation of the vehicle system 1 and the log management device 100 of this embodiment will be described below. FIG. 2 is a sequence diagram showing the processing of the vehicle system of the first embodiment. As shown in FIG. 2, the log management device communication unit 101 of the log management device 100 of the in-vehicle device 10 periodically transmits a command to each of the in-vehicle devices 11, 12, and 13 requesting the transmission of management information to the log management device communication unit 101 (S101). Note that, hereinafter, a command requesting the transmission of management information to the log management device communication unit 101 may be referred to as a management information request. Each of the in-vehicle devices 11, 12, and 13 that receives the management information request transmits management information to the in-vehicle device 10 (S102, S103, S104).

[0022] 3 is a table showing an available space management table according to the first embodiment. As shown in the available space management table in FIG. 3, the management information is information in which the identification information of the on-board devices 10, 11, 12, and 13 and the available space in the log recording unit 111 of the on-board devices 10, 11, 12, and 13 are associated and recorded in the management information recording unit 103. As shown in FIG. 2, when the log management device communication unit 101 of the log management device 100 of the on-board device 10 receives the management information, the information management unit 104 updates the management information recorded in the management information recording unit 103 to the management information received by the log management device communication unit 101 (S105).

[0023] 2, an event that requires a log to be recorded occurs in the in-vehicle device 12 (S106). An event that requires a log to be recorded means, for example, a condition that triggers the recording of a log. In this embodiment, when the state of the vehicle equipped with the vehicle system 1 satisfies a specific condition, the recording of a log, which is time-series data, is triggered.

[0024] Specifically, an event refers to a change in the state of a vehicle equipped with the vehicle system 1, such as sudden braking, sudden acceleration, sharp turning, or a large impact on the vehicle. An event also refers to a change in the state of software in a vehicle equipped with the vehicle system 1, such as an error occurring in a computer program loaded in the vehicle. An event also refers to a specific condition being met by an internal or external situation of a vehicle equipped with the vehicle system 1, which is necessary for learning AI (artificial intelligence) used inside or outside the vehicle. An event also refers to the detection of a sign of a cyber-attack.

[0025] The capacity determination unit 113 of the in-vehicle device 12 determines that there is insufficient free space for recording logs (S107). The in-vehicle device communication unit 114 of the in-vehicle device 12 transmits management information including insufficient capacity information to the log management device (S108). The insufficient capacity information is information regarding the insufficient free space in the log recording unit 111 that records logs. The insufficient capacity information includes the data size of the logs that need to be recorded by the in-vehicle device 12 that transmitted the management information including the insufficient capacity information. The operation of the in-vehicle device 12 when an event occurs will be described below.

[0026] 4 is a flowchart showing the process when an event occurs in the in-vehicle device 12 of the first embodiment. As shown in FIG. 4, an event occurs in the in-vehicle device 12 (S201). When the log recording control unit 112 records a log in the log recording unit 111 in response to the occurrence of the event, if the capacity determination unit 113 determines that there is sufficient free space (S202), the log recording control unit 112 records the log in the log recording unit 111 (S203). On the other hand, when the log recording control unit 112 records a log in the log recording unit 111 in response to the occurrence of the event, if the capacity determination unit 113 determines that there is sufficient free space (S202), the in-vehicle device communication unit 114 transmits management information including insufficient capacity information to the log management device 100 of the in-vehicle device 10 (S204).

[0027] As shown in FIG. 2 , when the log management device communication unit 101 of the log management device 100 of the in-vehicle device 10 receives management information including insufficient capacity information, the proxy recording destination determination unit 102 refers to the management information recorded in the management information recording unit 103 and determines the in-vehicle device 11 that will record the log instead of the in-vehicle device 12 that transmitted the management information including the insufficient capacity information (S109). Hereinafter, recording a log instead of the in-vehicle device 12 that transmitted the management information including the insufficient capacity information may be referred to as proxy recording. Also, the in-vehicle device 11 that records a log instead of the in-vehicle device 12 that transmitted the management information including the insufficient capacity information may be referred to as a proxy recording destination. Also, the in-vehicle device 11 that records a log instead of the in-vehicle device 12 that transmitted the management information including the insufficient capacity information may be referred to as a proxy recording destination. The operation of determining the proxy recording destination will be described below.

[0028] 5 is a flowchart showing the process of determining the in-vehicle device 11 as the proxy recording destination in the first embodiment. As shown in FIG. 5, the log management device communication unit 101 receives management information including insufficient capacity information (S301). Thereafter, the proxy recording destination determination unit 102 repeatedly performs loop processing for the in-vehicle devices 10, 11, 12, and 13 listed in the free capacity management table shown in FIG. 3 (S302).

[0029] The proxy recording destination determination unit 102 refers to the data size of the log that the in-vehicle device 12 needs to record, which is included in the capacity shortage information, and determines the in-vehicle device 11 that will record the log instead of the in-vehicle device 12 that sent the management information including the capacity shortage information. Specifically, it is determined whether the free space in the log recording unit 111 of the in-vehicle devices 10, 11, 12, and 13 exceeds the data size of the log that the in-vehicle device 12 needs to record (S303).

[0030] When the free space in the log recording unit 111 of each of the in-vehicle devices 10, 11, 12, and 13 exceeds the data size of the log that the in-vehicle device 12 needs to record (S303), the proxy recording destination determination unit 102 turns on the proxy recording enable flags of the in-vehicle devices 10, 11, 12, and 13 (S304). The proxy recording enable flags are information, such as binary values ​​like 1 and 0, that indicate whether each of the in-vehicle devices 10, 11, 12, and 13 can serve as a proxy recording destination. For example, when each of the in-vehicle devices 10, 11, 12, and 13 is on and can serve as a proxy recording destination, the proxy recording enable flag is set to 1.

[0031] The proxy recording destination determination unit 102 also acquires the number of logs being recorded on behalf of the in-vehicle unit 12 that transmitted the management information including the insufficient capacity information (S305). On the other hand, if the available capacity of the log recording unit 111 of the in-vehicle unit 10, 11, 12, or 13 does not exceed the data size of the logs that the in-vehicle unit 12 needs to record (S303), the proxy recording destination determination unit 102 leaves the proxy recording enable flag at 0 (OFF) and acquires the number of logs being recorded on behalf of the in-vehicle unit 12 that transmitted the management information including the insufficient capacity information (S305). The proxy recording destination determination unit 102 similarly executes the loop process for the in-vehicle units 10, 11, 12, and 13 listed in the available capacity management table shown in FIG. 3 (S302 to S306).

[0032] 6 is a table showing the free space management table of FIG. 3 with a substitute recording enable flag. As shown in FIG. 6, the substitute recording enable flags for the in-vehicle devices 10, 11, and 13 other than the in-vehicle device 12 that transmitted the management information including the insufficient capacity information are set to 1, indicating that the in-vehicle device can serve as a substitute recording destination. Note that the in-vehicle device 12 that transmitted the management information including the insufficient capacity information transmitted the management information including the insufficient capacity information because it lacked the free space for recording logs, as described above. Therefore, the substitute recording enable flag for the in-vehicle device 12 that transmitted the management information including the insufficient capacity information is set to 0, indicating that the in-vehicle device cannot serve as a substitute recording destination.

[0033] 7 is a table showing a log recording destination management table according to the first embodiment. As shown in the log recording destination management table in Fig. 7, the management information is information in which the in-vehicle device 11, 12, or 13 that transmitted the management information including the capacity shortage information when an event occurred, the in-vehicle device 10, 11, 12, or 13 that is the proxy recording destination, and the number of logs recorded as the proxy recording destination are associated and recorded in the management information recording unit 103.

[0034] The proxy recording destination determination unit 102 determines the vehicle-mounted device 11, among the vehicle-mounted devices 10, 11, 13 capable of recording logs of the data size included in the capacity shortage information, which has recorded the largest number of logs instead of the vehicle-mounted device 12 that transmitted the management information including the capacity shortage information, as the proxy recording destination of the vehicle-mounted device 12 that transmitted the management information including the capacity shortage information.

[0035] This is because it is easier to manage the log recording when the same in-vehicle devices 11, 12, and 13 perform proxy recording for each of the in-vehicle devices 11, 12, and 13. In the example of FIG. 7 , among the in-vehicle devices 10, 11, and 13 that are proxy recording destinations for the in-vehicle device 12, the in-vehicle device 11 records the largest number of logs on behalf of the in-vehicle device 12. Therefore, as shown in FIG. 5 , the proxy recording destination determination unit 102 determines the in-vehicle device 11, which records the largest number of logs on behalf of the in-vehicle device 12, as the proxy recording destination (S307). Note that the method for determining the proxy recording destination is not limited to this method. For example, among the in-vehicle devices 10, 11, 12, and 13, the in-vehicle device 10, which has the largest amount of free space, may be determined as the proxy recording destination.

[0036] 2, the log management device communication unit 101 transmits a log transmission request to the in-vehicle device 12 that transmitted the management information including the capacity shortage information, which is a command to transmit a log to the in-vehicle device 11 that has been determined as the proxy recording destination by the proxy recording destination determination unit 102 (S110). The in-vehicle device 12 that received the log transmission request transmits the log to the in-vehicle device 11 that is the proxy recording destination (S111). The in-vehicle device 11 that received the log records the log on behalf of the in-vehicle device 12 that transmitted the management information including the capacity shortage information (S112).

[0037] After the in-vehicle device 12 that transmitted the management information including the capacity shortage information transmits the log to the in-vehicle device 11 determined by the proxy recording destination determination unit 102, the log management device communication unit 101 transmits a command to the in-vehicle device 12 that transmitted the management information including the capacity shortage information, requesting that the log be deleted (S113). Note that, hereinafter, a command to the in-vehicle device 12 that transmitted the management information including the capacity shortage information, requesting that the log be deleted, may be referred to as a log deletion request. The in-vehicle device 12 that received the log deletion request deletes the log from the log recording unit 111 (S114).

[0038] In this embodiment, the proxy recording destination determination unit 102 determines the in-vehicle device 11 that will record the log instead of the in-vehicle device 12 that transmitted the management information, based on management information regarding the available capacity for recording the log. Furthermore, the log management device communication unit 101 transmits a command to the in-vehicle device 12 that transmitted the management information, requesting that the log be transmitted to the in-vehicle device 11 determined as the proxy recording destination by the proxy recording destination determination unit 102. In other words, according to this embodiment, the possibility that a log can be recorded in any of the in-vehicle devices 10, 11, 12, and 13 is increased. Therefore, in this embodiment, the number of logs that can be recorded in the in-vehicle devices 10, 11, 12, and 13 can be increased.

[0039] Furthermore, in this embodiment, the log management device communication unit 101 periodically transmits a command to each of the in-vehicle devices 11, 12, and 13 requesting that the in-vehicle devices 11, 12, and 13 transmit management information to the log management device communication unit 101. When the log management device communication unit 101 receives the management information, the information management unit 104 updates the management information recorded in the management information recording unit 103 to the management information received by the log management device communication unit 101. Therefore, the periodically updated management information is recorded in the management information recording unit 103 of the log management device 100.

[0040] Furthermore, in this embodiment, when the log management device communication unit 101 receives management information including capacity shortage information regarding a lack of free space, the proxy recording destination determination unit 102 refers to the management information recorded in the management information recording unit 103 and determines the in-vehicle device 11 as a proxy recording destination for recording logs instead of the in-vehicle device 12 that transmitted the management information including the capacity shortage information. The log management device communication unit 101 transmits a command to the in-vehicle device 12 that transmitted the management information including the capacity shortage information, requesting that the log be transmitted to the in-vehicle device 11 determined as the proxy recording destination by the proxy recording destination determination unit. Therefore, when an event requiring log recording occurs in the in-vehicle device 12, the log management device communication unit 101 determines the in-vehicle device 11 as the proxy recording destination based on the periodically updated management information and causes the in-vehicle device 12 to transmit the log to the in-vehicle device 11 as the proxy recording destination.

[0041] Furthermore, in this embodiment, the proxy recording destination determination unit 102 refers to the data size of the log that needs to be recorded, which is included in the capacity shortage information, and determines the in-vehicle device 11 that will record the log instead of the in-vehicle device 12 that transmitted the management information including the capacity shortage information. This makes it possible to determine the in-vehicle device 11 that is the proxy recording destination and that is capable of performing proxy recording with a higher probability.

[0042] Furthermore, in this embodiment, the proxy recording destination determination unit 102 determines, among the in-vehicle devices 10, 11, and 13 that can record logs of the data size included in the capacity shortage information, the in-vehicle device 11 that has the largest number of logs recorded as the proxy recording destination of the in-vehicle device 12 that transmitted the management information including the capacity shortage information, as the proxy recording destination of the in-vehicle device 12. As a result, the same in-vehicle devices 11, 12, and 13 often perform proxy recording for each of the in-vehicle devices 11, 12, and 13, making it easier to manage the log recording.

[0043] In this embodiment, after the in-vehicle device 12 that sent the management information including the capacity shortage information sends the log to the in-vehicle device 11 determined by the proxy recording destination determination unit 102, the log management device communication unit 101 sends a command to the in-vehicle device 12 that sent the management information including the capacity shortage information to request the deletion of the log. This prevents the same log from being recorded twice in the in-vehicle devices 10, 11, 12, and 13, and increases the number of logs that can be newly recorded.

[0044] Furthermore, in this embodiment, when the log recording control unit 112 records a log in the log recording unit 111 in response to the occurrence of an event, if the capacity determination unit 113 determines that there is sufficient free space, the log recording control unit 112 records the log in the log recording unit 111. On the other hand, when the log recording control unit 112 records a log in the log recording unit 111 in response to the occurrence of an event, if the capacity determination unit 113 determines that there is sufficient free space, the in-vehicle device communication unit 114 transmits management information including information about the lack of capacity to the log management device 100. Therefore, when an event occurs that requires the recording of a log with a large data size, it is possible to increase the number of logs that can be recorded.

[0045] Second Embodiment A second embodiment will now be described. The configuration of the vehicle system 1 of this embodiment is similar to that of the vehicle system 1 of the first embodiment shown in FIG. 1 , and therefore will not be described again. FIG. 8 is a sequence diagram showing the processing of the vehicle system of the second embodiment. In the first embodiment, the occurrence of an event triggers the transmission of a log transmission request. However, in this embodiment, the free space in the management information, which is periodically updated, is referenced, and a log transmission request is transmitted to an in-vehicle device 12 that is determined to have low free space.

[0046] As shown in Fig. 8, similar to the first embodiment, the log management device communication unit 101 of the log management device 100 of the in-vehicle device 10 periodically transmits a management information request to each of the in-vehicle devices 11, 12, and 13 (S401). Each of the in-vehicle devices 11, 12, and 13 that has received the management information request transmits management information to the in-vehicle device 10 (S402, S403, S404). As shown in Fig. 8, similar to the first embodiment, when the log management device communication unit 101 of the log management device 100 of the in-vehicle device 10 receives management information, the information management unit 104 updates the management information recorded in the management information recording unit 103 to the management information received by the log management device communication unit 101 (S405).

[0047] 9 is a table showing the free space management table of the second embodiment. As shown in the free space management table of Fig. 9, the management information is information in which the identification information of the on-board devices 10, 11, 12, and 13, the free space in the log recording unit 111 of the on-board devices 10, 11, 12, and 13, and a log transmission target flag are associated and recorded in the management information recording unit 103.

[0048] The log transmission target flag is information, for example, using two values ​​such as 1 and 0, indicating whether each of the in-vehicle devices 11, 12, and 13 is a target for transmission of a log transmission request. For example, if each of the in-vehicle devices 10, 11, 12, and 13 is a target for transmission of a log transmission request from the log management device 100 of the in-vehicle device 10, the log transmission target flag is ON, 1. On the other hand, if each of the in-vehicle devices 10, 11, 12, and 13 is not a target for transmission of a log transmission request from the log management device 100 of the in-vehicle device 10, the log transmission target flag is OFF, 0.

[0049] 8, the proxy recording destination determination unit 102 refers to the management information recorded in the management information recording unit 103 and determines whether the available capacity of the management information is less than an arbitrary threshold (S406). Fig. 10 is a flowchart showing the process of determining the in-vehicle device 12 to which the log transmission request is to be sent in the second embodiment.

[0050] 10, the proxy recording destination determination unit 102 repeatedly performs loop processing for the in-vehicle devices 10, 11, 12, and 13 listed in the free space management table shown in Fig. 9 (S501). The proxy recording destination determination unit 102 determines whether the free space in the log recording unit 111 of each of the in-vehicle devices 10, 11, 12, and 13 is less than a threshold (S502).

[0051] If the free space in the log recording unit 111 of the in-vehicle units 10, 11, 12, and 13 is less than the threshold (S502), the proxy recording destination determination unit 102 sets the log transmission target flag of the in-vehicle units 10, 11, 12, and 13 to ON (1) (S503). On the other hand, if the free space in the log recording unit 111 of the in-vehicle units 10, 11, 12, and 13 is not less than the threshold (S502), the proxy recording destination determination unit 102 leaves the log transmission target flag to OFF (0) (S504). The proxy recording destination determination unit 102 similarly executes loop processing for the in-vehicle units 10, 11, 12, and 13 listed in the free space management table shown in FIG. 9 (S501 to S504).

[0052] 11 is a table showing the free space management table of FIG. 9 in which the log transmission target flag has been changed as described above. As shown in FIG. 11, for example, when the threshold value is set to 100, the log transmission target flag of the in-vehicle device 12 whose free space is less than 100 is set to ON (1). On the other hand, the log transmission target flags of the in-vehicle devices 10, 11, and 13 whose free space is more than 100 are set to OFF (0).

[0053] 8, the proxy recording destination determination unit 102 determines the in-vehicle device 10 as the proxy recording destination (S407). In this embodiment, the proxy recording destination determination unit 102 determines the in-vehicle device 10 with the largest amount of free space as the proxy recording destination among the in-vehicle devices 10, 11, 12, and 13. However, as in the first embodiment, the proxy recording destination determination unit 102 may also determine the in-vehicle device 11 with the largest number of recorded logs as the proxy recording destination for the in-vehicle device 12 with free space less than 100, among the in-vehicle devices 10, 11, and 13 with free space greater than 100.

[0054] The log management device communication unit 101 transmits a log transmission request, which is a command to request the transmission of a log to the in-vehicle device 10 determined by the proxy recording destination determination unit 102, to the in-vehicle device 12 whose available capacity is less than the threshold (S408). Fig. 12 is a flowchart showing the process of transmitting a log transmission request according to the second embodiment. As shown in Fig. 12, the proxy recording destination determination unit 102 repeatedly performs loop processing for the in-vehicle devices 10, 11, 12, and 13 listed in the available capacity management table shown in Fig. 11 (S601). The proxy recording destination determination unit 102 determines whether the log transmission target flags of the in-vehicle devices 10, 11, 12, and 13 are ON (S602).

[0055] When the log transmission target flags of the in-vehicle devices 10, 11, 12, and 13 are ON (S602), the log management device communication unit 101 transmits a log transmission request to the in-vehicle devices 10, 11, 12, and 13 whose log transmission target flags are ON (S603). On the other hand, when the log transmission target flags of the in-vehicle devices 10, 11, 12, and 13 are OFF (S602), the log management device communication unit 101 does not transmit a log transmission request to the in-vehicle devices 10, 11, 12, and 13 whose log transmission target flags are OFF, and proceeds to S604. The log management device communication unit 101 similarly executes the loop process for the in-vehicle devices 10, 11, 12, and 13 listed in the free space management table shown in FIG. 11 (S601 to S604).

[0056] 8, after receiving the log transmission request, the in-vehicle device 12 whose free space is less than the threshold transmits the logs that have been recorded in the log recording unit 111 to the in-vehicle device 10, which is the proxy recording destination (S409). The logs that have been recorded in the log recording unit 111 up to that point include logs that need to be recorded due to events that have occurred in the past.

[0057] 13 is a flowchart showing the process of transmitting a log to the in-vehicle device 10 that is the proxy recording destination in the second embodiment. As shown in FIG. 13, after receiving a log transmission request (S701), the in-vehicle device 12 transmits identification information, the event occurrence time, and the log to the in-vehicle device 10 that is the proxy recording destination (S702). The identification information is information that identifies the in-vehicle device 12 that received the log transmission request. The event occurrence time is the time when the event that triggered the recording of the log occurred.

[0058] 8 , after the in-vehicle device communication unit 114 of the in-vehicle device 10 receives the identification information, the event occurrence time, and the log from the in-vehicle device 12, the log recording control unit 112 of the in-vehicle device 10 records the log in the log recording unit 111 as a proxy (S410). After the in-vehicle device 12 that received the log transmission request transmits the log to the in-vehicle device 10 determined by the proxy recording destination determination unit 102, the log management device communication unit 101 transmits a command to the in-vehicle device 12 that received the log transmission request to request the deletion of the log (S411).

[0059] 14 is a flowchart showing a process in which the in-vehicle device 10, which is the proxy recording destination, records a log according to the second embodiment. As shown in FIG. 14, the in-vehicle device communication unit 114 of the in-vehicle device 10 receives a log from the in-vehicle device 12 (S801). The log includes identification information and the time of event occurrence. The log recording control unit 112 of the in-vehicle device records the log in the log recording unit 111 (S802). The information management unit 104 updates the management information recorded in the management information recording unit 103 based on the log recorded in the log recording unit 111 (S803).

[0060] 15 is a table showing a log recording management table according to the second embodiment. As shown in the log recording management table of FIG. 15, the management information is information in which identification information, a log, and an event time are associated and recorded in the management information recording unit 103. As described above, the identification information is information for identifying the in-vehicle device 12 that received the log transmission request and transmitted the log. The event occurrence time is the occurrence time of the event that triggered the log. In other words, in this embodiment, the management information recording unit 103 has management information for managing the time and from which in-vehicle device 11, 12, or 13 the log was received.

[0061] As shown in Fig. 14, after updating the management information (S803), the log management device communication unit 101 transmits a log deletion request to the in-vehicle device 12 that received the log transmission request (S804). As shown in Fig. 8, similar to the first embodiment, the in-vehicle device 12 that received the log deletion request deletes the log from the log recording unit 111 (S412). Since the in-vehicle device 12 deletes the log and increases the free space in the log recording unit 111, even if an event that requires log recording occurs thereafter (S413), the in-vehicle device 12 can record the log in the log recording unit 111 (S414).

[0062] In this embodiment, the proxy recording destination determination unit 102 refers to the periodically updated management information recorded in the management information recording unit 103, and when the free space in the management information is less than a threshold, determines an in-vehicle device 10 that will record logs instead of an in-vehicle device 12 whose free space is less than the threshold. The log management device communication unit 101 transmits a command to the in-vehicle device 12 whose free space is less than the threshold, requesting that the in-vehicle device 12 transmit a log to the in-vehicle device 10 determined by the proxy recording destination determination unit 102. Therefore, even if the in-vehicle device 10 does not receive management information including information about insufficient space due to the occurrence of an event from the in-vehicle device 11, 12, or 13, the log transmission request can be transmitted based on the periodically updated management information, and the number of logs that can be recorded in the in-vehicle devices 10, 11, 12, and 13 can be increased.

[0063] [Third Embodiment] A third embodiment will now be described. The configuration of the vehicle system 1 of this embodiment is similar to that of the vehicle system 1 of the first embodiment shown in Fig. 1, and therefore description thereof will be omitted. Fig. 16 is a sequence diagram showing processing of the vehicle system of the third embodiment. As in the first embodiment, in this embodiment as well, the occurrence of an event triggers the transmission of a log transmission request.

[0064] However, in this embodiment, the proxy recording destination determination unit 102 does not directly determine the proxy recording destination in-vehicle device 10, 11, 12, 13. In this embodiment, the log management device communication unit 101 sends a command to the in-vehicle devices 11, 12, 13, requesting a response as to whether or not a log can be recorded on behalf of the in-vehicle device 12 that sent the management information including the insufficient capacity information. The proxy recording destination determination unit 102 determines, as the proxy recording destination, the in-vehicle device 11 that sent a response indicating that a log can be recorded on behalf of the in-vehicle device 12 that sent the management information including the insufficient capacity information.

[0065] 16 , an event that requires a log to be recorded occurs in the in-vehicle device 12 (S901). The capacity determination unit 113 of the in-vehicle device 12 determines that there is insufficient free space for recording the log (S902). The in-vehicle device communication unit 114 of the in-vehicle device 12 transmits management information including insufficient capacity information to the log management device (S902). The insufficient capacity information includes the data size of the log that needs to be recorded by the in-vehicle device 12 that transmitted the management information including the insufficient capacity information.

[0066] 17 is a flowchart showing the process when an event occurs in the in-vehicle device 12 according to the third embodiment. As shown in FIG. 17 , an event occurs in the in-vehicle device 12 (S1001). When the log recording control unit 112 records a log in the log recording unit 111 in response to the occurrence of the event, if the capacity determination unit 113 determines that there is sufficient free space (S1002), the log recording control unit 112 records the log in the log recording unit 111 (S1003).

[0067] On the other hand, when the log recording control unit 112 records a log in the log recording unit 111 in response to the occurrence of an event, if the capacity determination unit 113 determines that there is insufficient free space (S1002), the in-vehicle device communication unit 114 transmits management information including insufficient capacity information to the log management device 100 of the in-vehicle device 10 (S1004).

[0068] As described above, the management information includes the capacity shortage information, which includes the data size of the log that needs to be recorded by the in-vehicle device 12 that transmitted the management information including the capacity shortage information. The management information may also include a proxy recording destination search request. The proxy recording destination search request is information requesting the log management device 100 and the in-vehicle devices 10, 11, 12, and 13 to search for the in-vehicle devices 10, 11, 12, and 13 that are proxy recording destinations. After transmitting the management information including the capacity shortage information to the log management device 100 of the in-vehicle device 10 (S1004), the in-vehicle device 12 transitions to a state of waiting for a log transmission request (S1005).

[0069] 16, when the log management device communication unit 101 receives management information including capacity shortage information regarding a lack of free space, the log management device communication unit 101 transmits a command to the in-vehicle devices 10, 11, and 13, excluding the in-vehicle device 12 that transmitted the management information including the capacity shortage information, requesting an answer as to whether or not a log can be recorded on behalf of the in-vehicle device 12 that transmitted the management information including the capacity shortage information. Note that, hereinafter, the command requesting an answer as to whether or not a log can be recorded on behalf of the in-vehicle device 12 that transmitted the management information including the capacity shortage information may be referred to as a proxy recording permission / prohibition answer request.

[0070] 18 is a flowchart showing the processing performed when insufficient capacity information and a proxy recording destination search request are received according to the third embodiment. As shown in FIG. 18, the log management device communication unit 101 receives management information including insufficient capacity information (S1101). As described above, the management information may include a proxy recording destination search request. The log management device communication unit 101 then transmits a proxy recording availability response request to the in-vehicle units 10, 11, and 13, excluding the in-vehicle unit 12 that transmitted the management information including the insufficient capacity information (S1102).

[0071] The log management device communication unit 101 includes the data size of the log in a command requesting an answer as to whether or not a log can be recorded on behalf of the in-vehicle device 12 that transmitted the management information including the capacity shortage information. Note that if the management information includes a proxy recording destination search request, the log management device communication unit 101 may transfer the management information received from the in-vehicle device 12 as a proxy recording availability answer request to the in-vehicle devices 10, 11, and 13. Even when the management information received from the in-vehicle device 12 is a proxy recording availability answer request, the proxy recording availability answer request includes the data size of the log.

[0072] 16, for example, when the in-vehicle device 11 that has received the proxy recording permission response request transmits to the in-vehicle device 10, if proxy recording is possible, a response indicating that the log can be recorded on behalf of the in-vehicle device 12 that transmitted the management information including the capacity shortage information (S906). FIG. 19 is a flowchart showing the processing performed when the in-vehicle device 11 of the third embodiment receives a proxy recording permission response request.

[0073] 19 , the in-vehicle device communication unit 114 of the in-vehicle device 11 receives a proxy recording permission response request (S1201). When the log recording control unit 112 determines that the free space in the log recording unit 111 exceeds the data size of the log of the in-vehicle device 12 (S1202), the in-vehicle device communication unit 114 transmits a response indicating that the log can be recorded on behalf of the in-vehicle device 12 that transmitted the management information including the capacity shortage information (S1203).

[0074] On the other hand, when the log recording control unit 112 determines that the free space in the log recording unit 111 exceeds the data size of the log of the in-vehicle device 12 (S1202), it transmits a response indicating that the log cannot be recorded on behalf of the in-vehicle device 12 that transmitted the management information including the insufficient capacity information (S1204). Note that, hereinafter, the response indicating that the log can be recorded on behalf of the in-vehicle device 12 that transmitted the management information including the insufficient capacity information may be referred to as a proxy recording possible response. The proxy recording possible response may be transmitted by the in-vehicle device 10 to the log management device communication unit 101 of the log management device 100 by the above-described processing.

[0075] 16 , when the log management device communication unit 101 receives a response indicating that a log can be recorded instead of the in-vehicle device 12 that transmitted the management information including the insufficient capacity information, the proxy recording destination determination unit 102 determines the in-vehicle device 11 that transmitted the response indicating that a log can be recorded instead of the in-vehicle device 12 that transmitted the management information including the insufficient capacity information as the in-vehicle device 11 that will record the log instead of the in-vehicle device 12 that transmitted the management information including the insufficient capacity information (S907). The log management device communication unit 101 transmits a command to the in-vehicle device 12 that transmitted the management information including the insufficient capacity information, requesting that the log be transmitted to the in-vehicle device 11 determined by the proxy recording destination determination unit 102 (S908).

[0076] 20 is a flowchart showing the process performed when a proxy recording enable response is received according to the third embodiment. As shown in FIG. 20, the log management device communication unit 101 receives the proxy recording enable response (S1301). The proxy recording destination determination unit 102 determines whether the proxy recording enable response received flag is already ON (S1302).

[0077] The proxy recording enable response received flag is information indicating whether or not a proxy recording enable response has already been received from each of the in-vehicle units 10, 11, 12, and 13 after the log management device communication unit 101 transmitted a proxy recording enable response request. The proxy recording enable response received flag is recorded in the management information recording unit 103 as management information in association with the in-vehicle units 10, 11, 12, and 13. If the proxy recording enable response received flag is ON, it means that a proxy recording enable response has already been received. If the proxy recording enable response received flag is OFF, it means that a proxy recording enable response has not yet been received.

[0078] If the proxy recording enable response received flag is already ON (S1302), the proxy recording destination determination unit 102 discards the proxy recording enable response (S1303) to prevent duplicate logs from being sent to the in-vehicle devices 10, 11, 12, and 13. On the other hand, if the proxy recording enable response received flag is not ON (S1302), the proxy recording destination determination unit 102 turns ON the proxy recording enable response received flag recorded in association with the in-vehicle device 11, and determines the in-vehicle device 11 as the proxy recording destination (S1304). The log management device communication unit 101 transmits a log transmission request to the in-vehicle device 12 that transmitted the management information including the capacity shortage information (S1305).

[0079] In addition, if there are multiple in-vehicle devices 10, 11, and 13 that can serve as proxy recording destinations in the above processing, as in the first and second embodiments described above, the in-vehicle device 11 that has the largest number of logs recorded as the proxy recording destination for the in-vehicle device 12 may be determined as the proxy recording destination for the in-vehicle device 12, or the in-vehicle device 10 with the largest amount of free space may be determined as the proxy recording destination.

[0080] 16 , upon receiving the log transmission request, the in-vehicle device 12 transmits the log to the in-vehicle device 11, which is the proxy recording destination (S909). The in-vehicle device 11 that received the log records the log on behalf of the in-vehicle device 12 that transmitted the management information including the capacity shortage information (S910). After the in-vehicle device 12 that transmitted the management information including the capacity shortage information transmits the log to the in-vehicle device 11 determined by the proxy recording destination determination unit 102, the log management device communication unit 101 transmits a log deletion request to the in-vehicle device 12 that transmitted the management information including the capacity shortage information (S911). The in-vehicle device 12 that received the log deletion request deletes the log from the log recording unit 111 (S912).

[0081] According to this embodiment, the log management device communication unit 101 receives management information including capacity shortage information regarding a lack of free space. The log management device communication unit 101 transmits a proxy recording availability response request to the in-vehicle devices 10, 11, and 13, excluding the in-vehicle device 12 that transmitted the management information including the capacity shortage information. The proxy recording destination determination unit 102 determines the in-vehicle device 11 that has received the proxy recording availability response from the log management device communication unit 101 as the proxy recording destination. Because the proxy recording destination determination unit 102 does not directly reference the management information to determine the proxy recording destination, the processing load on the log management device 100 can be reduced.

[0082] Furthermore, according to this embodiment, the insufficient capacity information includes the data size of the log that needs to be recorded by the in-vehicle device 12 that transmitted the management information including the insufficient capacity information, and the log management device communication unit 101 transmits the proxy recording availability response request including the log data size. Therefore, the in-vehicle device 10, 11, 13 that receives the proxy recording availability response request can determine with a high probability whether proxy recording is possible.

[0083] Although the embodiments of the present disclosure have been described in detail above using the drawings, the specific configuration is not limited to this embodiment, and even if there are design changes and the like within the scope that does not deviate from the gist of the present disclosure, they are included in the present disclosure.

[0084] DESCRIPTION OF SYMBOLS 1... Vehicle system 10... In-vehicle device 11, 12, 13... In-vehicle device 50... Communication bus 100... Log management device 101... Log management device communication unit 102... Proxy recording destination determination unit 103... Management information recording unit 104... Information management unit 111... Log recording unit 112... Log recording control unit 113... Capacity determination unit 114... In-vehicle device communication unit

Claims

1. A log management device that manages the recording of logs by multiple in-vehicle devices, comprising: a log management device communication unit that receives management information regarding available capacity for recording the logs from one of the in-vehicle devices; and a proxy recording destination determination unit that determines the in-vehicle device that will record the log instead of the in-vehicle device that sent the management information based on the management information received by the log management device communication unit, wherein the log management device communication unit sends a command to the in-vehicle device that sent the management information, requesting that the log be sent to the in-vehicle device determined by the proxy recording destination determination unit.

2. A log management device as described in claim 1, comprising: a management information recording unit that records the management information in each of the in-vehicle devices; and an information management unit that manages the management information recorded in the management information recording unit, wherein the log management device communication unit periodically transmits to each of the in-vehicle devices a command requesting the transmission of the management information to the log management device communication unit, and when the log management device communication unit receives the management information, the information management unit updates the management information recorded in the management information recording unit to the management information received by the log management device communication unit.

3. The log management device described in claim 2, characterized in that when the log management device communication unit receives the management information including capacity shortage information regarding the lack of free space, the proxy recording destination determination unit refers to the management information recorded in the management information recording unit and determines the vehicle-mounted device to record the log instead of the vehicle-mounted device that sent the management information including the capacity shortage information, and the log management device communication unit sends a command to the vehicle-mounted device that sent the management information including the capacity shortage information, requesting that the log be sent to the vehicle-mounted device determined by the proxy recording destination determination unit.

4. The log management device described in claim 3, characterized in that the capacity shortage information includes the data size of the log that needs to be recorded by the vehicle-mounted device that transmitted the management information including the capacity shortage information, and the proxy recording destination determination unit refers to the data size included in the capacity shortage information to determine the vehicle-mounted device that will record the log instead of the vehicle-mounted device that transmitted the management information including the capacity shortage information.

5. The log management device described in claim 4, characterized in that the proxy recording destination determination unit determines, among the on-board devices capable of recording the log of the data size, the on-board device that has the largest number of logs recorded on behalf of the on-board device that transmitted the management information including the capacity shortage information, as the on-board device that will record the log on behalf of the on-board device that transmitted the management information including the capacity shortage information.

6. The log management device of claim 5, characterized in that after the vehicle-mounted device that transmitted the management information including the capacity shortage information transmits the log to the vehicle-mounted device determined by the proxy recording destination determination unit, the log management device communication unit transmits a command to the vehicle-mounted device that transmitted the management information including the capacity shortage information, requesting the deletion of the log.

7. The log management device described in claim 2, characterized in that the proxy recording destination determination unit refers to the management information recorded in the management information recording unit, and when the free space of the management information is less than a threshold, determines the vehicle-mounted device to record the log instead of the vehicle-mounted device whose free space is less than the threshold, and the log management device communication unit sends a command to the vehicle-mounted device whose free space is less than the threshold, requesting that the log be sent to the vehicle-mounted device determined by the proxy recording destination determination unit.

8. The log management device according to claim 1, characterized in that when the log management device communication unit receives the management information including capacity shortage information regarding the lack of free space, the log management device communication unit transmits a command to the in-vehicle devices excluding the in-vehicle device that transmitted the management information including the capacity shortage information, requesting an answer as to whether the log can be recorded in place of the in-vehicle device that transmitted the management information including the capacity shortage information; when the log management device communication unit receives an answer that the log can be recorded in place of the in-vehicle device that transmitted the management information including the capacity shortage information, the substitute recording destination determination unit determines the in-vehicle device that transmitted the answer that the log can be recorded in place of the in-vehicle device that transmitted the management information including the capacity shortage information as the in-vehicle device that will record the log in place of the in-vehicle device that transmitted the management information including the capacity shortage information; and the log management device communication unit transmits a command to the in-vehicle device that transmitted the management information including the capacity shortage information, requesting that the log be transmitted to the in-vehicle device determined by the substitute recording destination determination unit.

9. The log management device of claim 8, characterized in that the capacity shortage information includes the data size of the log that needs to be recorded by the vehicle-mounted device that transmitted the management information including the capacity shortage information, and the log management device communication unit transmits a command requesting an answer as to whether the log can be recorded on behalf of the vehicle-mounted device that transmitted the management information including the capacity shortage information, including the data size.

10. The log management device of claim 9, characterized in that after the vehicle-mounted device that transmitted the management information including the capacity shortage information transmits the log to the vehicle-mounted device determined by the proxy recording destination determination unit, the log management device communication unit transmits a command to the vehicle-mounted device that transmitted the management information including the capacity shortage information, requesting the deletion of the log.

11. A vehicle system comprising the log management device of claim 3 and a plurality of the on-board devices, wherein one of the on-board devices comprises: a log recording unit that records the log; a log recording control unit that records the log in the log recording unit in response to the occurrence of an event that requires the log to be recorded; a capacity determination unit that determines whether the free space in the log recording unit is insufficient; and an on-board device communication unit that transmits the management information to the log management device and transmits the log to other on-board devices, wherein when the log recording control unit records the log in the log recording unit in response to the occurrence of the event, if the capacity determination unit determines that the free space is not insufficient, the log recording control unit records the log in the log recording unit; and when the log recording control unit records the log in the log recording unit in response to the occurrence of the event, if the capacity determination unit determines that the free space is insufficient, the on-board device communication unit transmits the management information including the capacity insufficiency information to the log management device.

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