JP2020155941A - Vehicle control device - Google Patents

Abstract

To suppress the processing load associated with a change in communication speed.SOLUTION: A vehicle control device 101 includes a plurality of ECUs 10A and 20A for controlling a vehicle. The ECUs 10A and 20A include signal quality measuring units 11 and 21 for transmitting and receiving predetermined signals that allow the signal quality of the communication signals to be measured between the ECUs 10A and 20A and communication speed change units 12 and 22 that change the communication speed of the communication signals, respectively. The signal quality measuring units 11 and 21 measure the signal quality when a driving mode of the vehicle is changed. The communication speed change units 12 and 22 change the communication speed according to difference of the signal quality.SELECTED DRAWING: Figure 1

Description

The present invention relates to a vehicle control device.

The vehicle control device includes a plurality of ECUs (Electronic Control Units). Various communication methods are adopted for communication between a plurality of ECUs. The communication speed between a plurality of ECUs is increasing. However, since disturbances such as noise are generated during traveling, there is a trade-off relationship between noise immunity and communication speed.

Patent Document 1 discloses a technique for easily setting an appropriate communication speed in consideration of noise immunity according to a traveling state of a vehicle. In the technique of Patent Document 1, the communication speed is forcibly increased or decreased when the system is started, when the vehicle is accelerated or decelerated, and when the error rate is detected in the communication data.

Japanese Unexamined Patent Publication No. 2000-307592

In the technique of Patent Document 1, the communication speed can be changed according to the situation of the system. However, since the communication speed is frequently switched and changed, there is a problem that the processing load increases for each switching process.

The present invention is for solving the above problems, and an object of the present invention is to provide a technique capable of suppressing a processing load due to a change in communication speed.

The vehicle control device according to the present invention is a vehicle control device including a plurality of control units for controlling the vehicle, and the plurality of control units can measure the signal quality of a communication signal between the plurality of control units. The signal quality measuring unit includes a signal quality measuring unit for transmitting and receiving the signal of the above and a communication speed changing unit for changing the communication speed of the communication signal, and the signal quality measuring unit measures the signal quality when the driving mode of the vehicle is changed. , The communication speed changing unit changes the communication speed according to the difference in signal quality.

According to the present invention, it is possible to suppress the processing load due to the change in communication speed.

The block diagram which shows the whole structure of the vehicle control device which concerns on Example 1. FIG. FIG. 6 is a schematic view showing a data transmission / reception operation between ECUs according to the first embodiment. The schematic diagram which shows the transmission operation of the training signal by the ECU 10A which concerns on Example 1. FIG. The schematic diagram which shows the transmission operation of the training signal by the ECU 20A which concerns on Example 1. FIG. FIG. 5 is a flowchart illustrating the operation of the vehicle control device according to the first embodiment. The block diagram which shows the whole structure of the vehicle control device which concerns on Example 2. The schematic diagram which shows the transmission / reception operation of the training signal between ECUs which concerns on Example 2. FIG. The schematic diagram which shows the transmission / reception operation at the time of changing the operation mode which concerns on Example 2. The flowchart explaining the operation of the vehicle control device which concerns on Example 2. The flowchart explaining the measurement signal quality information storage process which concerns on Example 2. FIG. The block diagram which shows the whole structure of the vehicle control device which concerns on Example 3.

Hereinafter, some embodiments will be described with reference to the accompanying drawings. It should be noted that the present embodiment is merely an example for realizing the present invention and does not limit the technical scope of the present invention. The same reference numerals are given to the common configurations in each figure.

FIG. 1 is a block diagram showing an overall configuration of the vehicle control device according to the first embodiment.

The vehicle control device 101 is mounted on the vehicle. The vehicle control device 101 includes a plurality of ECUs as an example of a "control unit" that controls the vehicle. The plurality of ECUs are an ECU 10A and an ECU 20A.

The ECU 10A includes a signal quality measuring unit 11, a communication speed changing unit 12, a transmission / reception processing unit 13, a communication interface 14, and an operation mode management unit 15.

The ECU 20A includes a signal quality measuring unit 21, a communication speed changing unit 22, a transmission / reception processing unit 23, a communication interface 24, and an operation mode management unit 25. The signal quality measuring unit 21, the communication speed changing unit 22, the transmission / reception processing unit 23, the communication interface 24, and the operation mode management unit 25 are the same as the elements having the same name included in the ECU 10A. Therefore, in the following, the description of the signal quality measuring unit 21, the communication speed changing unit 22, the transmission / reception processing unit 23, the communication interface 24, and the operation mode management unit 25 will be omitted.

The ECU 10A and the ECU 20A are connected via a communication path A. As the communication path A, a network compliant with standards such as CAN (Controller Area Network) (registered trademark), LIN (Local Interconnect Network), FlexRay, MOST (Media Oriented Systems Transport), and Ethernet (registered trademark) may be used. .. The ECU 10A and the ECU 20A have the same configuration. However, the ECU 10A and the ECU 20A do not necessarily have the same configuration, and may have different configurations. For example, the signal quality measuring units 11 and 21 may include only one of the ECU 10A and the ECU 20A instead of including both the ECU 10A and the ECU 20A.

The signal quality measuring unit 11 transmits and receives a training signal as a “predetermined signal” capable of measuring the signal quality of the communication signal between the ECU 10A and the ECU 20A. The signal quality may be the error rate or delay of the communication signal. The training signal is, for example, continuous data of “0”, and is a signal whose signal quality of the communication signal can be measured on the receiving side. The communication method of the training signal may be a communication method that can also be used as a signal for enabling the function of the automatic equalizer. The transmission time of the training signal, the data type, and the specifications of the communication method are not particularly limited and may be changed according to the applied vehicle control device. The communication speed of the training signal may be set higher than that of other communication signals. Thereby, the detection time of the signal quality of the communication signal can be shortened.

The communication speed changing unit 12 changes the communication speed of the communication signal transmitted and received between the ECU 10A and the ECU 20A according to the difference in the signal quality of the communication signal. The difference in signal quality may be the difference between the reference range of signal quality (for example, the error rate is less than 1%) and the measured value of signal quality measured by the signal quality measuring unit 11. The communication speed changing unit 12 may gradually change the communication speed of the communication signal to the target value, or may change it once. The transmission / reception processing unit 13 transmits / receives data via the communication interfaces 14 and 24. The driving mode management unit 15 manages the driving mode of the vehicle. Here, the operation mode may be a driving mode, a failure state, or a low power consumption mode such as an electric vehicle. The travel mode may include idling, acceleration, deceleration, and constant speed travel.

FIG. 2 is a schematic view showing a data transmission / reception operation between ECUs according to the first embodiment.

When the ECU 10A transmits data to the ECU 20A via the communication path A, the ECU 20A receives the transmitted data. On the other hand, when the ECU 20A transmits data to the ECU 10A via the communication path A, the ECU 10A receives the transmitted data. That is, FIG. 2 shows an example in which the ECU 10A and the ECU 20A alternately execute the data transmission operation and the data reception operation. However, the ECU 10A and the ECU 20A do not necessarily have to alternately operate the data transmission operation and the data reception operation. One of the ECU 10A and the ECU 20A may be a master that executes a data transmission operation, and the other may be a slave that executes a data reception operation.

FIG. 3 is a schematic view showing a training signal transmission operation by the ECU 10A according to the first embodiment. FIG. 3 describes the operation when the operation mode is changed at the point A in FIG.

The ECU 10A transmits a training signal transmission command instructing a preset communication speed according to the operation mode to the ECU 20A. Upon receiving the training signal transmission command, the ECU 20A transmits an ACK signal indicating a response to the ECU 10A. Upon receiving the ACK signal transmitted from the ECU 20A, the ECU 10A transmits a training signal to the ECU 20A.

When the ECU 20A receives the training signal transmitted from the ECU 10A, the signal quality measuring unit 21 measures the signal quality of the communication signal. After that, the ECU 20A transmits an ACK signal indicating the completion of reception of the training signal and signal quality information to the ECU 10A. The ECU 10A receives the signal quality information transmitted from the ECU 20A. At this time, when the signal quality information is within a predetermined reference range (for example, the error rate is less than 1%), the communication speed changing unit 12 of the ECU 10A changes the data communication speed according to the signal quality information. Shift to data transmission operation according to the changed communication speed.

Note that FIG. 3 shows a case where the signal quality information transmitted from the ECU 20A for the first time is within a predetermined reference range. However, if the signal quality information transmitted from the ECU 20A is outside the predetermined reference range, the communication speed of the training signal is changed (for example, changed to a low speed), and the training signal transmission command is transmitted / received and the ACK signal is transmitted / received again. , Send and receive signal quality information. The above description is a sequence for executing transmission / reception of a training signal transmission command, transmission / reception of an ACK signal, and transmission / reception of signal quality information. This sequence is an example and is not limited thereto.

FIG. 4 is a schematic view showing a training signal transmission operation by the ECU 20A according to the first embodiment. FIG. 4 describes the operation when the operation mode is changed at the point B of FIG. The difference from FIG. 3 is that the operations of the ECU 10A and the ECU 20A are reversed, and the transmission / reception method of each signal is the same. Therefore, the description of the operation of the ECU 10A and the ECU 20A will be omitted.

FIG. 5 is a flowchart illustrating the operation of the vehicle control device according to the first embodiment.

The operation of the first embodiment will be described more specifically with reference to the flowchart of FIG. Hereinafter, the operation of the ECU 10A for transmitting the training signal will be mainly described. The operation of the ECU 20A transmitting the training signal is the same as the operation of the ECU 10A transmitting the training signal, and thus the description thereof will be omitted.

First, the ECU 10A starts the communication control process (S100).

Next, the ECU 10A determines whether or not it is the start of system startup (S101). If the determination result of S101 is true (S101: YES), the process proceeds to S102. If the determination result in S101 is false (S101: NO), the process proceeds to step 103.

In S102, the ECU 10A sets an initial value of the communication speed. After that, the ECU 10A proceeds to the process of S111.

In S103, the operation mode management unit 15 of the ECU 10A determines whether or not the operation mode has been changed. If the determination result of S103 is true (S103: YES), the process proceeds to S104. If the determination result of S101 is false (S103: NO), the process proceeds to S111.

In S104, the ECU 10A sets an initial value of the communication speed of the training signal calculated in advance according to the operation mode.

In S105, the ECU 10A transmits a training signal to the ECU 20A.

In S106, the ECU 10A determines whether or not the training signal has been transmitted. If the determination result in S106 is false (S106: NO), the process returns to the process in S105. If the determination result in S106 is true (S106: YES), the process proceeds to S107.

In S107, the ECU 10A receives the signal quality information measured by the signal quality measuring unit 21 of the ECU 20A.

In S108, the ECU 10A determines whether or not the signal quality of the communication signal is within a predetermined reference range based on the signal quality information. If the determination result in S106 is false (S108: NO), the process proceeds to S109. If the determination result in S106 is true (S108: YES), the process proceeds to S110.

In S109, the ECU 10A changes the communication speed of the training signal to a low speed.

In S110, the communication speed changing unit 12 of the ECU 10A sets the data communication speed to the communication speed based on the signal quality information of the training signal.

The ECU 10A inputs transmission data for which the communication speed is set to the transmission / reception processing unit 13, and transmits the transmission data input to the transmission / reception processing unit 13 via the communication interface 14, the communication path A, and the communication interface 24 of the ECU 20A. It is transmitted to the transmission / reception processing unit 23 (S111). In this way, in the communication control process, the ECU 10A ends the data transmission for which the communication speed is set (S112).

As described above, according to the first embodiment, the vehicle control device 101 transmits and receives a training signal capable of measuring the signal quality when the driving mode of the vehicle is changed, measures the signal quality of the communication signal, and determines the signal quality. The communication speed is determined according to the difference. As a result, it is possible to suppress the processing load when changing the communication speed according to the operation mode.

Next, the vehicle control device according to the second embodiment will be described with reference to FIGS. 6 to 10.

FIG. 6 is a block diagram showing an overall configuration of the vehicle control device according to the second embodiment. In FIG. 6, the same components as those in FIG. 1 are designated by the same reference numerals, and duplicate description will be omitted below.

In the second embodiment, the ECU 10B and the ECU 20B have additional components added to the components of the first embodiment. That is, the ECU 10B and the ECU 20B include a communication path B as an example of the "first communication path", measurement signal quality measurement units 11B and 21B, measurement transmission / reception processing units 13B and 23B, and measurement communication interfaces 14B and 24B. Is further provided in addition to the components of the first embodiment. In the second embodiment, the vehicle control device 102 transmits / receives a training signal via a dedicated communication path B, and transmits / receives a communication signal other than the training signal via a communication path A as an example of the “second communication path”. It is possible. The communication path A and the communication path B are not limited to the same communication specifications, and at least one of the communication specifications and the communication speed may be different. For example, the communication speed of the communication path B may be set higher than the communication speed of the communication path A. As a result, the detection time of the communication signal in the communication path B can be shortened. The measurement signal quality measurement units 11B and 21B and the measurement transmission / reception processing units 13B and 23B may be configured to be shared with the normal signal quality measurement units 11 and 21 and the transmission / reception processing units 13 and 23.

FIG. 7 is a schematic view showing a training signal transmission / reception operation between ECUs according to the second embodiment.

In FIG. 7, the communication path A shows a normal data transmission / reception operation, and similarly to FIG. 2, the ECU 10B and the ECU 20B alternately execute a data transmission operation and a data reception operation. On the other hand, in the communication path B, the ECU 10B and the ECU 20B alternately transmit and receive training signals at a preset communication speed. The ECU 10B and the ECU 20B store measurement signal quality information when receiving a training signal. In FIG. 7, the transmission / reception timings of the communication path A and the communication path B do not necessarily have to be synchronized.

FIG. 8 is a schematic view showing a transmission / reception operation when the operation mode is changed according to the second embodiment.

At the point C in FIG. 7, when the operation mode is changed, the vehicle control device 102 shifts to the measurement signal quality acquisition waiting process. The waiting time differs depending on the vehicle control device to be applied, is not particularly specified, and may not have a waiting time.

After the waiting time elapses, at the point D in FIG. 7, the measurement signal quality measurement unit 11B acquires the measurement signal quality information, and transmits the speed change command according to the measurement signal quality information to the ECU 20B. Upon receiving the speed change command, the ECU 20B returns an ACK signal indicating a response to the ECU 10B. When the ECU 10B receives the ACK signal transmitted from the ECU 20B, the ECU 10B shifts to the data transmission operation according to the changed communication speed.

FIG. 8 is an example in which the ECU 10B changes the communication speed. However, the ECU 20B may change the communication speed. In that case, the operations of the ECU 10B and the ECU 20B are reversed. However, since the transmission / reception method of each signal is the same, the operation description will be omitted.

FIG. 9 is a flowchart for explaining the operation of the vehicle control device according to the second embodiment, and FIG. 10 is a flowchart for explaining the measurement signal quality information storage process according to the second embodiment.

The operation of the second embodiment will be described more specifically with reference to the flowcharts of FIGS. 9 and 10.

In the flowchart of FIG. 9, the steps having the same contents as the steps of FIG. 5 have the same step numbers in FIG. 9, and therefore the detailed description thereof will not be given. In the following, the operation when the ECU 10B changes the communication speed will be mainly described. The operation when the ECU 20B changes the communication speed is also the same. Therefore, the description of the operation when the ECU 20B changes the communication speed will be omitted.

In the flowchart of FIG. 9, the ECU 10B executes the measurement signal quality acquisition waiting process after the process of S103 (S120).

Next, in the ECU 10B, the measurement signal quality measurement unit 11B acquires the measurement signal quality information (S121).

The ECU 10B compares the communication speed preset according to the signal quality information for measurement with the current communication speed, and whether or not it is necessary to change the communication speed according to the difference (delay) in these communication speeds. Is determined (S122). When the determination result of S122 is true (S122: YES), the ECU 10B proceeds to the process of S110. When the determination result of S122 is false (S122: NO), the ECU 10B proceeds to the process of S111.

FIG. 10 is a flowchart illustrating the measurement signal quality information storage process according to the second embodiment. The measurement signal quality information storage process is a process for storing the measurement signal quality information acquired in step 121 of FIG.

First, the ECU 10B starts the measurement signal quality information storage process (S130).

Next, the ECU 10B sets an initial value of the communication speed of the measurement training signal (S131). In the second embodiment, the communication speed of the training signal for measurement is a fixed value. However, for example, the communication speed of the measurement training signal may be changed according to the operation mode.

The ECU 10B receives the measurement training signal (S132).

The ECU 10B determines whether or not the reception of the measurement training signal is completed (S133). If the determination result of S122 is false (S133: NO), the process returns to the process of S132. If the determination result in S122 is true (S133: YES), the process proceeds to step 134.

The ECU 10B stores the measurement signal quality information of the received measurement training signal (S134).

In this way, the ECU 10B ends the measurement signal quality information storage process (S135).

As described above, according to the second embodiment, since the training signal transmission / reception processing at the time of changing the driving mode of the vehicle is executed via the communication path B, it is omitted in the communication path A. Therefore, as compared with the first embodiment, the processing load when changing the communication speed according to the operation mode can be further suppressed.

Next, the vehicle control device according to the third embodiment will be described with reference to FIG.

FIG. 11 is a block diagram showing an overall configuration of the vehicle control device according to the third embodiment.

The vehicle control device 103 of the third embodiment includes external data management units 16 and 26 instead of the operation mode management units 15 and 25 of the vehicle control device 10 of the first embodiment. The external data management units 16 and 26 manage the external environment of the vehicle as external data. The external environment of the vehicle may be, for example, the temperature, humidity, and rainfall detected by various sensors such as a temperature sensor, a humidity sensor, and a rainfall sensor. The block diagram of Example 2 (FIG. 6) can be replaced in the same manner as the block diagram of Example 1 (FIG. 1). Here, the replaced block diagram of the second embodiment is omitted.

The vehicle control devices 101 and 102 of the first and second embodiments measured the signal quality information when the operation mode was changed. The vehicle control device 103 of the third embodiment transmits and receives a training signal for measuring the signal quality when the external data management units 16 and 26 detect a change in the external environment (temperature, humidity, rainfall, etc.) of the vehicle. And change the communication speed according to the difference in signal quality. The change in the external environment may be, for example, a change in temperature of 1 ° C., a change in humidity of 1%, or a change in rainfall of 10 mm per hour.

As described above, according to the third embodiment, the vehicle control device 103 can change the communication speed even when the external data such as the temperature changes, and the communication speed is changed according to the operation mode. It is possible to suppress the processing load at the time of performing.

The present invention is not limited to the above-described examples, and includes various modifications. For example, each of the above-described embodiments has been described in detail in order to explain the present invention in an easy-to-understand manner, and is not necessarily limited to those having all the described configurations. Further, it is possible to replace a part of the configuration of one embodiment with the configuration of another embodiment, and further, it is possible to add the configuration of another embodiment to the configuration of one embodiment. Further, it is possible to add, delete, or replace a part of the configuration of each embodiment with another configuration.

101, 102, 103 ... Vehicle control device, 10A, 10B, 10C, 20A, 20B, 20C, ... ECU, 11,21 ... Signal quality measurement unit, 12, 22 ... Communication speed change unit, 16, 26 ... External data management Units, 11B, 21B ... Measurement signal quality measurement unit, A, B ... Communication path

Claims (7)

A vehicle control device having a plurality of control units for controlling a vehicle.
The plurality of control units
A signal quality measuring unit that transmits and receives a predetermined signal capable of measuring the signal quality of a communication signal between the plurality of control units, and a signal quality measuring unit.
A communication speed changing unit for changing the communication speed of the communication signal is provided.
The signal quality measuring unit measures the signal quality when the driving mode of the vehicle is changed.
The communication speed changing unit is a vehicle control device that changes the communication speed according to the difference in signal quality. A vehicle control device having a plurality of control units for controlling a vehicle.
The plurality of control units
A signal quality measuring unit that transmits and receives a predetermined signal capable of measuring the signal quality of a communication signal between the plurality of control units, and a signal quality measuring unit.
A communication speed changing unit for changing the communication speed of the communication signal is provided.
The signal quality measuring unit measures the signal quality when detecting a change in the external environment of the vehicle.
The communication speed changing unit is a vehicle control device that changes the communication speed according to the difference in signal quality. The signal quality is the error rate or delay of the communication signal.
The difference in signal quality is the difference between the reference range or reference value of the signal quality and the signal quality measured by the signal quality measuring unit.
The vehicle control device according to claim 1 or 2. A plurality of communication paths for connecting the plurality of control units are provided.
The plurality of communication paths are a first communication path in which the predetermined signal is transmitted / received and a second communication path in which a communication signal other than the predetermined signal is transmitted / received.
The vehicle control device according to claim 3. The communication speed is different between the first communication path and the second communication path.
The vehicle control device according to claim 4. The communication speed of the predetermined signal is set higher than that of other communication signals.
The vehicle control device according to claim 3. The communication speed changing unit gradually changes the communication speed.
The vehicle control device according to claim 3.

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