JP2020082953A - Network system - Google Patents

Abstract

To provide a network system which is suppressed in an increase of a processing load of a center processing ECU which performs plurality of kinds of processing for controlling a vehicle.SOLUTION: A network system is mounted to a vehicle. The network system comprises a center processing ECU for performing a plurality of pieces of processing for controlling the vehicle, and a plurality of peripheral processing ECUs for receiving data from the center processing ECU, and controlling a sensor or an actuator arranged in the vehicle on the basis of the data. The center processing ECU comprises: an execution part for performing the plurality of pieces of processing; a load calculation part for calculating a processing load of the execution part; and an execution changeover part for making the peripheral processing ECUs perform a part of the processing which is performed by the execution part when the processing load calculated by the load calculation part exceeds a constant value, and making the execution part stop its execution.SELECTED DRAWING: Figure 2

Description

The present invention relates to a network system mounted on a vehicle or the like.

A vehicle is equipped with a network system including a plurality of buses. One or more in-vehicle devices called ECUs (Electronic Control Units) are connected to each bus. Each bus is connected to a gateway device, and the gateway device relays data between the buses. Each ECU typically includes a processor, transmits and receives data to and from each other via a bus, obtains information from a sensor included in the vehicle, and controls an actuator included in the vehicle to control the sensor included in the vehicle. Each function is shared and executed.

It has been proposed to reduce the processing load in such a network system. Patent Document 1 discloses that in a vehicle-mounted network system, a low-priority data frame is specified based on the current vehicle state, and transmission processing of the low-priority data frame and relay processing by a gateway are suppressed. There is. Further, Patent Document 2 discloses that in a vehicle-mounted network device, a high-priority data frame is specified based on the current vehicle state, and the illegal data detection process for the low-priority data frame is suppressed. ..

JP, 2018-98733, A JP, 2017-47835, A

By consolidating and integrating multiple processes for vehicle control that were shared by multiple ECUs and executed in one central processing ECU, it is possible to promote the sophistication and diversification of functions, and It is being considered to facilitate updating and addition. The method of the above-mentioned patent document can be applied to suppress the processing load of the central processing ECU, but not all data to be processed are given priority, and the effect is limited. Further, when the processing is shared by a plurality of ECUs, the dispersion of the processing load is dispersed, and the difference in the processing load between the normal time and the high load is limited. The difference in processing load from that under high load becomes large. Therefore, when processing is centralized in the central processing ECU, measures against a high load are particularly important, and a method of further suppressing the processing load is desired.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a network system that suppresses an increase in the processing load of a central processing ECU that executes a plurality of processes for controlling a vehicle.

In order to solve the above problems, one aspect of the present invention is a network system mounted on a vehicle, which receives a data from the central processing ECU that executes a plurality of processes for controlling the vehicle. Then, the central processing ECU includes a plurality of peripheral processing ECUs that respectively execute control of a sensor or an actuator included in the vehicle based on the data, and the central processing ECU determines an execution unit that executes a plurality of processes and a processing load of the execution unit. When the load calculation unit to be calculated and the processing load calculated by the load calculation unit exceed a certain value, the peripheral processing ECU is caused to execute a part of the processing executed by the execution unit, and the execution unit stops the execution. A network system including an execution switching unit.

As described above, according to the present invention, it is possible to provide a network system that suppresses an increase in the processing load of the central processing ECU that executes a plurality of processes for controlling the vehicle.

Configuration diagram of a network system according to an embodiment of the present invention A flow chart showing an example of processing of central processing ECU concerning one embodiment of the present invention. The flowchart which shows the other example of the process of the central processing ECU which concerns on one Embodiment of this invention.

In the network system according to the present invention, the central processing ECU executes processing for realizing a plurality of functions for vehicle control. When the processing load of the central ECU becomes high, the predetermined processing among the processing that is normally executed by the central processing ECU is executed by peripheral processing ECUs other than the central processing ECU to increase the processing load of the central ECU. Suppress.

(Embodiment)
Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.

<Structure>
FIG. 1 shows the configuration of a network system 1 according to this embodiment. The network system 1 is mounted on a vehicle and includes a central processing ECU 10 as an ECU and one or more peripheral processing ECUs 21, 22, 23,.... The central processing ECU 10 and the peripheral processing ECUs 21, 22, 23,... Are connected via a bus 50. One or more sensors 31 and one or more actuators 41 are connected to the peripheral processing ECU 21. Similarly, one or more sensors 32 and one or more actuators 42 are connected to the peripheral processing ECU 22. In addition, one or more sensors 33 and one or more actuators 43 are connected to the peripheral processing ECU 23. The number of peripheral processing ECUs is not limited. A DCM (Data Communication Module) 60, which is an in-vehicle communication module, is connected to the central processing ECU 10, and can communicate with a specific server or the like outside the vehicle.

The central processing ECU 10 executes a plurality of processing for realizing each function of the vehicle based on the data received from the peripheral processing ECUs 21, 22, 23,... And the peripheral processing ECUs 21, 22, 23,. Send data that represents the result. Each function is, for example, a function for presenting information to the user called infotainment such as navigation, traffic information, audio, video, etc., an advanced driving support function called ADAS, an automatic driving function, and a vehicle exterior using wireless communication with the vehicle exterior. Coordinated service function, program update (OTA software update) function of central processing ECU 10 or peripheral processing ECUs 21, 22, 23,... Based on update data received by wireless communication with the outside of the vehicle, user's (driver's) line-of-sight direction, attention level, etc. Is a driver monitoring function for monitoring.

Each peripheral processing ECU 21, 22, 23,... Acquires information from the sensor connected to each, and transmits data to the central processing ECU 10 based on this, or based on the data received from the central processing ECU 10, It is possible to control sensors and actuators connected to each. The sensor is, for example, a vehicle speed sensor, a camera, a radar, a switch or the like, and acquires various states of the vehicle and its surroundings, an input by the user, and the like. The actuator is, for example, an output device of force, energy, information or the like such as an engine, a brake, a transmission, a power steering, an air conditioner and a navigation device. The peripheral processing ECU may be provided with only a sensor or only an actuator depending on its function. Further, the mode of connection between the peripheral processing ECU and the sensors and actuators is not limited, and a local bus may be used as shown in FIG. 1, or individual signal lines may be used for each sensor and each actuator. .. Also, both local buses and individual signal lines may be used.

Further, in the present embodiment, the central processing ECU 10 executes a communication monitoring function of detecting, when communication with the outside of the vehicle using the DCM 60 is received, which may cause a hindrance to the function of the vehicle, when the illegal data is received. can do. Since all the data received from the DCM 60 passes through the central processing ECU 10, the central processing ECU 10 has a communication monitoring function, so that comprehensive monitoring of data to be monitored without omission is possible. In the present embodiment, each of the peripheral processing ECUs 21, 22, 23,... Can also monitor data received by the device itself from the bus 50 and data between the device itself and the sensors and actuators connected to the device. it can. Since each peripheral processing ECU 21, 22, 23,... Has the communication monitoring function around the own device in this way, even if the communication monitoring function by the central processing ECU 10 is not operating, it is possible to perform monitoring without omission as a whole. Become. In the present embodiment, as will be described later, when the central processing ECU 10 is activated or when the load is below a predetermined value, the central processing ECU 10 executes processing for the communication monitoring function, and when it exceeds the predetermined value, , The peripheral processing ECUs 21, 22, 23,... Execute processing for the communication monitoring function.

The central processing ECU 10 includes an execution unit 11 that executes a process for each of the functions described above, a load calculation unit 12 that calculates a load described below, and an execution switching unit 13 that executes a process for reducing the load. Each of these units is realized by, for example, a computer including a CPU and a memory.

<Process>
FIG. 2 is a flowchart showing the processing of the central processing ECU 10 according to the example of the present embodiment. The processing will be described with reference to FIG. This process is started, for example, when the network system 1 is activated and the execution unit 11 of the central processing ECU 10 starts executing the communication monitoring function. During the operation of the central processing ECU 10, the execution unit 11 executes processing for a plurality of functions based on data received from the peripheral processing ECUs 21, 22, 23,.... Further, the execution unit 11 determines which of the non-operational functions among the functions other than the communication monitoring function of the central ECU 10 based on the data received from the peripheral processing ECUs 21, 22, 23,... ), and which of the functions in the operating state is set to the non-operating state (OFF) is determined.

(Step S101): The execution unit 11 proceeds to step S102 if the on/off state of each function changes as a result of the above determination. If there is no change in ON/OFF of each function, this step S101 is repeated.

(Step S102): If there is a function changed from ON to OFF, the execution unit 11 stops the execution of the process for that function. Even if there is a function that has changed from off to on, in this step, execution of processing for that function is not started.

(Step S103): The load calculation unit 12 calculates the processing load of the central processing ECU 10 based on the load value associated with the function that is currently on. The load value is, for example, a clock frequency or a memory usage amount required for the CPU that executes the process of the execution unit 11 in order to execute each function. The load calculation unit 12 holds in advance a table in which each function is associated with its load value. Table 1 below shows an example of the table. The load calculation unit 12 can refer to the table to acquire the load value of the function in the ON state, and calculate the total value of the load values as the processing load of the central processing ECU 10, for example. It should be noted that such a table may be set based on a design value or may be set based on a learning value during a past operation.

(Step S104): The execution switching unit 13 compares the latest processing load of the central processing ECU 10 calculated in step S103 with the processing load calculated last time. As a result of the comparison, if the processing load has changed by a predetermined amount, the process proceeds to step S105, and if not, the process proceeds to step S106. The predetermined change is a change that can be considered that the previous processing load is less than or equal to a predetermined value, the latest processing load is larger than the predetermined value, and the processing load increases from within the allowable range to outside the allowable range, or This is a change that can be considered that the previous processing load is larger than the predetermined value, the latest processing load is less than or equal to the predetermined value, and the processing load is reduced from outside the allowable range to within the allowable range. When the processing load is first calculated after the start of this processing, the processing load calculated last time does not exist, so the latest processing load may be compared with the initial value 0, for example.

As the predetermined value, a first predetermined value and a second predetermined value smaller than the first predetermined value are set, the previous processing load is less than or equal to the first predetermined value, and the latest processing load is larger than the first predetermined value. In this case, and when the previous processing load is greater than the second predetermined value and the latest processing load is less than or equal to the second predetermined value, it may be determined that the predetermined change has occurred. In this way, the frequency with which it is determined that the predetermined change has occurred decreases, the frequency with which the process proceeds to step S105 described below decreases, and the frequency with which the ECUs that execute the predetermined process are switched decreases. The operation of the network system 1 becomes stable.

(Step S105): The execution switching unit 13 switches the ECU that executes the process for the communication monitoring function between the central processing ECU 10 and the peripheral processing ECUs 21, 22, 23,.... When the latest processing load becomes larger than the previous processing load and the process proceeds to this step, the execution unit 11 is executing the process for the communication monitoring function. The execution switching unit 13 transmits data indicating an instruction to the peripheral processing ECUs 21, 22, 23,... To start executing processing for the communication monitoring function, and causes the execution unit 11 to perform processing for the communication monitoring function. Stop the execution of. As a result, the processing load on the execution unit 11 can be suppressed.

Further, when the latest processing load becomes smaller than the previous processing load and the process proceeds to this step, the peripheral processing ECUs 21, 22, 23,... Execute the processing for the communication monitoring function. The execution switching unit 13 causes the execution unit 11 to start the execution of the process for the communication monitoring function, transmits the data representing the instruction to the peripheral processing ECUs 21, 22, 23,... Stop the execution of.

(Step S106): If there is a function changed from off to on in step S101, execution of the process for that function is actually started in this step. If the execution unit 11 stops the execution of the process for the function changed from ON to OFF in step S102, or stops the execution of the process for the communication monitoring function in step S105, it surely stops the execution. Then, the processing load is reduced to start the execution of the processing for the function changed from off to on. After this, the process proceeds to step S101, and the processes of steps S101 to S106 are repeated.

The above processing can be suitably executed when the load value for each function can be predicted in advance. The following is an example of a suitable process when it is difficult to predict the load value for each function. FIG. 3 is a flowchart showing the processing of the central processing ECU 10 according to another example of the present embodiment as described above. The processing will be described with reference to FIG. Descriptions of the same items as those in the above processing will be omitted or simplified.

(Step S201): The execution unit 11 determines which of the non-operating functions is to be in the operating state (ON) and which is in the non-operating state is to be in the non-operating state (OFF), as in Step S101 described above. To do. As a result of the determination, if the ON/OFF of each function is changed, the process proceeds to step S202. If there is no change in ON/OFF of each function, this step S201 is repeated.

(Step S202): Similar to step S102 described above, if there is a function that has changed from ON to OFF, the execution unit 11 actually stops the execution of the process for that function.

(Step S203): If there is a function that has changed from OFF to ON, the execution unit 11 actually starts execution of processing for that function.

(Step S204): The load calculation unit 12 calculates the current processing load of the central processing ECU 10. In this example, the processing load can be calculated using various state detection functions such as a load included in the CPU that executes the processing of the execution unit 11, for example.

(Step S205): The execution switching unit 13 compares the latest processing load of the central processing ECU 10 calculated in step S204 with a predetermined value. If the processing load is greater than the predetermined value, the process proceeds to step S206, and if the processing load is less than or equal to the predetermined value, the process proceeds to step S207. When the processing load is larger than the predetermined value, it can be considered that the processing load is outside the allowable range. When the processing load is less than or equal to the predetermined value, it can be considered that the processing load is within the allowable range.

(Step S206): When the peripheral processing ECUs 21, 22, 23,... Are executing the processing for the communication monitoring function, the execution switching section 13 does not perform any processing in this step and continues the state. .. When the execution unit 11 is executing the process for the communication monitoring function, the execution switching unit 13 transmits data representing an instruction to the peripheral processing ECUs 21, 22, 23,... The execution of the process is started, and the execution unit 11 stops the execution of the process for the communication monitoring function. As a result, the processing load on the execution unit 11 can be suppressed. After this, the process proceeds to step S201, and the processes of steps S201 to S207 are repeated.

(Step S207): When the execution unit 11 is executing the process for the communication monitoring function, the execution switching unit 13 does not perform any particular process in this step and continues the state. When the peripheral processing ECUs 21, 22, 23,... Are executing the process for the communication monitoring function, the execution switching unit 13 causes the executing unit 11 to start executing the process for the communication monitoring function, The data representing the instruction is transmitted to the processing ECUs 21, 22, 23,... And the execution of the processing for the communication monitoring function is stopped. After this, the process proceeds to step S201, and the processes of steps S201 to S207 are repeated.

This processing can be suitably executed even when the load value for each function cannot be predicted in advance. In each of the processing examples described above, the ECU that executes the processing for the communication monitoring function is switched between the central processing ECU 10 and the peripheral processing ECUs 21, 22, 23,... The central processing ECU 10 and the peripheral processing ECUs 21, 22, 23,... May be any other processing instead of the communication monitoring function as long as the processing can be executed.

<Effect>
With the above processing, in the network system 1 according to the present invention, when the processing load of the central processing ECU 10 becomes high, it is one of the processing for the communication monitoring function among the processing that is normally executed by the central processing ECU 10. Predetermined processing is executed by the peripheral processing ECUs 21, 22, 23,... Instead of the central processing ECU 10. As a result, the processing load on the central ECU can be prevented from increasing.

The present invention includes not only a network system but also a method for suppressing a processing load of an ECU in a network system, a processing load suppressing program executed by a computer of the ECU, a computer-readable non-transitory storage medium storing the program, and a network system. It can be regarded as a vehicle or the like. Further, the present invention can be applied to a network system other than the network system mounted on the vehicle.

The present invention is useful for network systems installed in vehicles and the like.

1 Network system 10 Central processing ECU
11 Execution Unit 12 Load Calculation Unit 13 Execution Switching Unit 21, 22, 23 Peripheral Processing ECU
31, 32, 33 sensor 41, 42, 43 actuator 50 bus 60 DCM

Claims (1)

A network system installed in a vehicle,
A central processing ECU that executes a plurality of processings for controlling a vehicle, and a plurality of peripheral processings that receive data from the central processing ECU and respectively control a sensor or an actuator included in the vehicle based on the data. And an ECU,
The central processing ECU is
An execution unit that executes the plurality of processes,
A load calculation unit that calculates the processing load of the execution unit;
When the processing load calculated by the load calculation unit exceeds a certain value, the execution switching unit that causes the peripheral processing ECU to execute a part of the processing executed by the execution unit and stops the execution by the execution unit. A network system comprising:

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