JP2020022019A - Vehicle system - Google Patents

Abstract

To enable a response to be performed from an on-vehicle ECU (electronic control unit) by reducing the amount of data to be communicated on a CAN even when response messages to be transmitted from the on-vehicle ECUs to a failure diagnostic tool is increased so that a network is highly loaded.SOLUTION: A vehicle system includes: multiple electronic control units 3 for controlling a vehicle; an on-vehicle network 2 to which the multiple electronic control units 3 are connected; a transmission section for periodically transmitting control data from the electronic control unit 3 via the on-vehicle network 2; a diagnosis section 5 for performing failure diagnosis of a vehicle; a response section for periodically performing a response of a result of failure diagnosis of the electronic control unit 3 that has received a periodical transmission request; and an instruction section for issuing a transmission suppressing instruction with respect to another electronic control unit 3 when the on-vehicle network 2 is highly loaded in performing a response of a result of failure diagnosis. A period for transmission of control data is allowed to be longer in the electronic control unit 3 that has transmitted a suppressing instruction and the other electronic control unit 3 that has received the suppressing instruction.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a vehicle system.

  As a background art of this technical field, there is Japanese Patent Application Laid-Open No. 2003-256033 (Patent Document 1). The summary column of Patent Document 1 states that a large number of ECUs, that is, ECU1, ECU2, ECU3,... Are connected to a bus 10 of an in-vehicle LAN wired in the vehicle. The failure diagnosis tool 20 is connected to the ECU 1, and the ECU 1 receives a request message from the failure diagnosis tool 20, transmits the request message to the ECU 2, and the like, and receives a response from the ECU 2 and the like. The ECU 1 transmits a request message to the ECU 2 or the like irrespective of a request from the failure diagnosis tool 20 for an item known in advance to be requested by the failure diagnosis tool 20, and saves a result of the response. It is described.

JP 2003-256033 A

  In the case of responding to a single request message with failure diagnosis information at a fixed cycle in response to a request message from the failure diagnosis tool, a plurality of in-vehicle ECUs simultaneously transmit responses to the failure diagnosis tool. Therefore, a large amount of data is transmitted including the vehicle control data that is periodically transmitted to the network, and the network is overloaded, resulting in a delay in the response from the vehicle-mounted ECU. Furthermore, there is a possibility that a response cannot be made at a constant cycle, and the failure diagnosis information may be missing.

  In view of the above, the present invention has been made in view of the above problems, and the number of response messages transmitted from the in-vehicle ECU to the failure diagnosis tool increases, and communication is performed on the CAN even when the network becomes heavily loaded. This reduces the amount of data and makes it possible to respond from the in-vehicle ECU.

  For example, in order to solve the above-mentioned problems, a plurality of electronic control devices for controlling a vehicle, a vehicle-mounted network to which the plurality of electronic control devices are connected, and periodic control from the electronic control device via the vehicle-mounted network A transmission unit for transmitting data for use, a diagnosis unit for performing a failure diagnosis of the vehicle, a response unit for periodically responding to a result of the failure diagnosis of the electronic control device that has received a periodic transmission request, When the load on the on-vehicle network is high at the time of the response as a result of the diagnosis, a command unit that performs a command to suppress transmission to the other electronic control device, the electronic control device that transmitted the suppression command, and the reception of the suppression command The other electronic control device described above lengthens the period for transmitting control data.

  ADVANTAGE OF THE INVENTION According to this invention, the amount of data communicated on CAN is reduced, the load of a network is reduced, and a response from an in-vehicle ECU is enabled. Further features related to the present invention will become apparent from the description of the present specification and the accompanying drawings. Problems, configurations, and effects other than those described above will be clarified by the following description of the embodiments.

FIG. 1 is an embodiment of a block diagram showing a configuration of a vehicle-mounted network system. It is a figure showing communication of the in-vehicle network which is an example of the present invention. 9 is a flowchart illustrating a task operation of the ECU when a failure diagnosis result request is received. It is a flowchart which shows the task operation | movement of ECU which received the transmission suppression command.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. The accompanying drawings show specific embodiments in accordance with the principles of the present invention, but these are for understanding the present invention, and are not used to limit the present invention.

  The vehicle is equipped with a plurality of in-vehicle ECUs (Electronic Control Units, electronic control units), each of which is connected by an in-vehicle network such as a CAN (Controller Area Network). At the time of vehicle diagnosis, a failure diagnosis tool (diagnosis unit) is connected to the in-vehicle network and performs dialog communication with the failure diagnosis tool and each in-vehicle ECU, thereby performing failure diagnosis of failure information etc. self-diagnosed by each in-vehicle ECU. Submit to the tool.

  The failure diagnosis tool transmits a message requesting data necessary for failure diagnosis to each vehicle-mounted ECU. Upon receiving the request message from the failure diagnosis tool, each in-vehicle ECU responds to the failure diagnosis tool with the requested failure diagnosis information in the request message.

  Since the in-vehicle ECUs cooperate, the in-vehicle network such as CAN is used not only for diagnosis but also for communicating information such as vehicle speed and engine speed required for vehicle control. Communication of information necessary for vehicle control is performed by transmission at an arbitrary cycle.

  In communication by the CAN network, an ID (identifier) is used to identify data contents and a transmission node according to ISO (International Organization for Standardization) 11898-1, and serves to determine the priority of communication arbitration. The priority of communication arbitration is defined such that the smaller the value of the ID, the higher the priority.

  For example, when transmission is performed simultaneously from a plurality of vehicle-mounted ECUs, a small ID is transmitted with priority, and a large ID is transmitted as soon as transmission is completed.

  The following embodiment relates to a technology that is used when controlling the operation of a vehicle and that reduces the amount of data communicated in an in-vehicle network and can secure a response time from an in-vehicle ECU.

  In the following embodiment, when the request message from the failure diagnosis tool is transmitted, the network is in a high load state, and if the in-vehicle ECU cannot respond, the in-vehicle ECU is transmitting from another in-vehicle ECU. A message for suppressing CAN transmission is transmitted to another in-vehicle ECU with an arbitrary ID having a higher priority than the ID. Other in-vehicle ECUs have a technology that reduces the load on the network by extending the period of information that is not affected even if the transmission period is extended among the data used for vehicle control after receiving the message. An in-vehicle control device becomes possible.

  FIG. 1 is a block diagram showing a configuration of the vehicle-mounted network system. The in-vehicle network system includes a bus 2 mounted on the vehicle 1, an ECU 5 for controlling the vehicle connected by the bus 2, and a diagnostic connector 4 for connecting the vehicle network of the vehicle 1 to the failure diagnostic tool 5. It is configured as follows.

  Further, a transmission unit (not shown) for periodically transmitting control data from the electronic control device 3 via the on-vehicle network (bus 2) transmits the result of the failure diagnosis of the electronic control device 3 which has received the periodic transmission request. A response unit (not shown) that periodically responds, and an instruction unit (not shown) that instructs the other electronic control devices 3 to suppress transmission when the load on the in-vehicle network is high at the time of responding to the result of the failure diagnosis.

  The ECU 3 includes a CPU, a ROM, a RAM, and a CAN controller inside. The ROM is a storage device that stores a control program executed by the CPU. The RAM is a storage device that stores data such as variables used while the CPU is executing the control program. The CAN controller is a device that transmits and receives data to and from the bus 2.

  In FIG. 1, the bus (vehicle-mounted network) 2 connected to the ECU 3 is one for the sake of explanation. However, in general, a plurality of networks such as a CAN network and a LIN (Local Interconnect Network) are connected by a gateway. I have.

  FIG. 2 is a schematic diagram showing communication of a CAN network on a vehicle-mounted network. The vertical axis of the figure shows the items of data transmitted and received on the CAN network and the CAN communication load 102, and the horizontal axis shows the time axis. As items of data transmitted and received on the CAN network, there are ECU1 130, ECU2 131, and ECU3 132 indicating transmission data from the failure diagnosis tool 101 and transmission of data on diagnosis from each ECU. The network load 102 indicates a network load due to data transmission from each ECU such as vehicle speed and engine speed required for vehicle control.

  In FIG. 2, for the sake of explanation, the network load indicated by the network load 102 is an expression in which a temporary high load state occurs intermittently. However, in actuality, data necessary for vehicle control and the like transmitted by each ECU is a plurality of data. Since the transmission cycle differs for each ID in addition to being performed by the ID, the network load is actually uneven.

  As one of the features of the CAN communication, an ID (identifier) is used to identify data contents and a transmission node, and the priority of communication arbitration is determined. In the CAN network shown in FIG. 2, description will be made as IDs having the following priorities.

  Request 191 of ECU2 131 <ID group transmitted by network load 102 <Request of failure diagnostic tool 101 <Response of ECU1 130 <Response of ECU2 131 <Response of ECU3 132.

  The ECU1 request 151, the ECU2 request 152, and the ECU3 request 153 transmitted from the failure diagnosis tool 101 to each ECU sequentially request the ECU1 130, the ECU2 131, and the ECU3 132 for a periodic response of the failure diagnosis result. Transmission data to be transmitted.

  The failure diagnosis tool 101 transmits an ECU1 request 151 to the ECU1 130 at an arbitrary timing. At this time, since the priority of the ECU1 request 151 is lower than the ID group transmitted by the network load 102, the ECU1 request 151 is transmitted at the timing when the network load 104 is interrupted.

  The ECU1 130 performs a failure diagnosis at the timing when the ECU1 request 151 transmitted from the failure diagnosis tool 101 is received, and transmits a response 1 161 which is the first cycle response data. At this time, since the load on the network load 104 is interrupted, the ECU 1 130 can immediately transmit the response 1 161.

  Next, the failure diagnosis tool 101 transmits an ECU2 request 152 requesting a periodic failure diagnosis to the ECU2131. Similarly to the transmission of the response 1 161 from the ECU 1 130, since the network load 104 has been interrupted, the request 152 from the failure diagnosis tool 101 to the ECU 2 is also transmitted immediately.

  The ECU2 131 performs a failure diagnosis at the timing when the ECU2 request 152 is received, and transmits the first cycle response data. However, the response 2 162 that is the second response of the ECU 1 130, the network load 104, and the ECU 3 request 153 that is a request for performing a failure diagnosis on the ECU 3 132 from the failure diagnosis tool 101 to the ECU 3 132 have a higher priority of the ID. Response 1 171 cannot respond.

  The ECU 2 has a transmission determination timer for measuring the transmission completion time of the ECU 2 and measures the time from when the request 152 is received to when the transmission is completed.

  When the transmission is not completed to the failure diagnosis tool 101 and the value of the transmission completion timer has passed 200 for an arbitrary time, the ECU 2 transmits a request 191 for instructing another ECU to suppress CAN transmission.

  The ECU 2 131 that has transmitted the request 191 and the ECU 1 130 and the ECU 3 132 that have received the request 191 extend the transmission cycle of the data used to control the vehicle, such as data for transmitting gear position information to the driver. Also suppresses CAN transmission by extending the period of the information that does not affect. Thereby, the load on the CAN network is reduced as in the control 105.

  Since the load on the network is reduced by the request 191 transmitted from the ECU 2 131, a response 3 163 of the ECU 1 130 having a higher priority among the responses of the ECUs is transmitted to the failure diagnosis tool 101. Subsequently, the response 1 171 of the ECU 2 and the response 1 181 of the ECU 3 are transmitted in accordance with the priority order of the ID.

  Next, FIG. 3 shows a task operation of the ECU that has received the transmission data requesting the periodic response of the failure diagnosis result transmitted from the failure diagnosis tool 101.

(S101)
First, it is determined whether a request has been received from the failure diagnosis tool 101 or whether a periodic response timing has been reached. When the request received from the failure diagnosis tool 101 is a periodic failure diagnosis, the periodic response timing determines whether or not the response timing has come after the initial response.
If the request has not been received from the failure diagnosis tool 101 or the periodic response timing has not been reached (N), there is no data to be transmitted or data is already being transmitted, so the transmission process is not performed (S104). Proceed to processing.

(S102)
If a request is received from the failure diagnosis tool 101 in (S101) or it is determined that the periodic response timing has been reached (Y), the response content (failure diagnosis result) generated by a process (not shown) is output to the failure diagnosis tool 101. Send to

(S103)
After the process of (S102), "0" is set to a transmission determination timer, which is a timer for measuring a time until the transmission is successful, and a transmission flag indicating that transmission has been performed at the same time is set.

(S104)
It is determined whether or not the transmission flag is set (Y) in (S103) (S104). If the transmission flag is not set (N), it is determined that there is no transmission request, and the process proceeds to (S108).

(S105)
When it is determined that the transmission flag is set (Y) in (S104), it is determined whether the transmission is actually completed.

(S106)
When it is determined that the transmission is completed (Y) in (S105), "0" is set to the transmission determination timer.
Further, since the transmission has been completed (Y), the transmission flag is cleared to prepare for the next data transmission.

(S107)
If it is determined in (S105) that the transmission has not been completed (Y), the transmission determination timer is incremented.

(S108)
The value of the transmission determination timer incremented in (S107) is compared with an arbitrary time. The arbitrary time is set within the time from the request of the failure diagnosis tool 101 determined by the failure diagnosis standard until each ECU responds. If the value of the transmission determination timer does not exceed the arbitrary time, nothing is performed because there is enough time until the ECU responds.

(S109)
When the value of the transmission determination timer exceeds an arbitrary time in (S108) (Y), it is determined that the network load is high, and the transmission cycle such as data for transmitting gear position information to other ECUs is determined. A transmission suppression command is transmitted to make a request to extend the transmission period of information that does not affect vehicle control even if the transmission is extended.
In order to reduce the network load, the ECU that has transmitted the transmission suppression command also performs processing to extend the transmission cycle of information that does not affect the vehicle even if the transmission cycle is extended.

  Next, FIG. 4 shows a task operation of the ECU that has received the transmission suppression command transmitted in (S109) of FIG.

(S201)
Each ECU determines the reception of the transmission suppression command transmitted in FIG. 3 (S109). If the transmission suppression command has not been received (N), the normal processing is continued without doing anything.

(S202)
If the transmission suppression command is received in (S201) (Y), control CAN data suppression processing (S202) for extending the transmission cycle of information that does not affect the vehicle even if the transmission cycle is extended is performed, and the network load is reduced. Lower.

According to the embodiment described above,
A plurality of electronic control units 3 for controlling the vehicle;
An in-vehicle network 2 to which a plurality of electronic control devices 3 are connected;
A transmission unit that periodically transmits control data from the electronic control unit 3 via the in-vehicle network 2,
A diagnostic unit 5 for diagnosing a failure of the vehicle;
A response unit that periodically responds to the result of the failure diagnosis of the electronic control device 3 that has received the periodic transmission request;
When the load on the in-vehicle network 2 is high at the time of responding to the result of the failure diagnosis, an instruction unit that instructs another electronic control unit 3 to suppress transmission.
The electronic control device 3 that has transmitted the suppression command and the other electronic control devices 3 that have received the suppression command increase the cycle of transmitting the control data.

Further, in an in-vehicle network used when controlling the operation of a vehicle,
A plurality of ECUs for controlling the vehicle,
A bus connected for communication between a plurality of ECUs,
A failure diagnosis tool for performing vehicle failure diagnosis from outside the vehicle,
It has a diagnostic connector for connecting the in-vehicle network and the failure diagnostic tool,
The in-vehicle network has an ID (identifier) for identifying a data content and a transmission node according to ISO (International Organization for Standardization) 11898-1 of a CAN (Controller Area Network) communication protocol. Communication arbitration that can perform transmission with priority,
In order to control the vehicle with a plurality of ECUs using an in-vehicle network, control data periodically transmitted from the plurality of ECUs;
A command for requesting any ECU connected to any bus from the failure diagnosis tool to periodically transmit a failure diagnosis result;
Any ECU that has received the request for periodic transmission of the failure diagnosis result performs a failure diagnosis and periodically responds with the result.
When the CAN communication load is high at the time of periodic response of the ECU failure diagnosis result, instructing other ECUs to suppress CAN transmission;
The ECU that has transmitted the CAN transmission suppression command and the other ECU that has received the suppression command reduce the CAN communication load by extending the period of transmission of the control data.

  In other words, when a request message is sent from the failure diagnosis tool and the in-vehicle ECU cannot respond when the network is under heavy load, the in-vehicle ECU has a higher priority than the IDs transmitted by the other in-vehicle ECUs. A message for suppressing CAN transmission is transmitted to another in-vehicle ECU with an arbitrary ID having a high value.

  After receiving the message, other in-vehicle ECUs determine the transmission cycle of data that is not affected even if the transmission cycle is extended, such as data used to convey the gear position to the driver, among the data used for vehicle control. By extending, the load on the network can be reduced.

1 ... vehicle 2 ... bus (vehicle network)
3 ... ECU (electronic control unit)
4 Diagnostic connector 5 Diagnostic tool (diagnosis unit)

Claims (3)

A plurality of electronic control units for controlling the vehicle,
An in-vehicle network to which a plurality of the electronic control devices are connected;
A transmission unit that periodically transmits control data from the electronic control device via the in-vehicle network,
A diagnosis unit that performs a failure diagnosis of the vehicle,
A response unit that periodically responds to the result of the failure diagnosis of the electronic control device that has received the periodic transmission request,
When the load of the in-vehicle network is high at the time of the response of the result of the failure diagnosis, comprising a command unit for performing a transmission suppression command to the other electronic control device,
A vehicle system in which the electronic control device that has transmitted the suppression instruction and the other electronic control device that has received the suppression instruction have a longer transmission cycle of control data. The vehicle system according to claim 1,
A vehicle system that transmits the suppression command having a higher priority than the control data based on an ID for identifying a priority. The vehicle system according to claim 1,
Having a timer to measure the time from the reception of the transmission request until the response of the response unit is completed,
A vehicle system that determines that the load on the in-vehicle network is high when the value of the timer has passed a predetermined time.

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