JP2014028547A - On-vehicle network system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an on-vehicle network system capable of efficiently using network environment by optimizing a transmission cycle of a communication message of a plurality of electronic control devices connected to a network.SOLUTION: This invention relates to the on-vehicle network system in which a plurality of electronic control devices mounted on a vehicle are connected through a communication line. In the on-vehicle network system, each of the plurality of electronic control devices includes vehicle state detection means for detecting a vehicle state, and communication control means for changing a transmission cycle obtained by presetting the transmission cycle of a communication message on the basis of the vehicle state detected by the vehicle state detection means.

Description

  The present invention relates to an in-vehicle network system, and more particularly, to an in-vehicle network system capable of efficiently using a network environment by optimizing the transmission cycle of communication messages of a plurality of electronic control devices connected to the network.

A vehicle includes a plurality of electronic control devices such as an engine control device, a transmission control device, a brake control device, and an air conditioning control device. A plurality of electronic control devices mounted on these vehicles are connected via a communication line to constitute an in-vehicle network system. In the in-vehicle network system, a LAN such as a CAN (Controller Area Network) is mainly used. The communication message of the electronic control device is transmitted by a communication frame used in communication such as CAN, and is periodically transmitted and received depending on the application.
In transmission / reception between a plurality of electronic control devices, it is not always necessary for all communication messages to be transmitted / received to / from each electronic control device in the same transmission cycle. Depending on vehicle conditions, unnecessary communication messages may be transmitted and received, which increases the processing load of the electronic control device and increases the network load, and hinders necessary information from being transmitted more quickly.
In a conventional in-vehicle network system, the number of signals on the in-vehicle network in which a plurality of electronic control devices are connected by CAN increases, and when the load increases, arbitration processing such as reducing the signal is performed, so that the network load is reduced. Some have secured communication when increasing. (JP 2010-28355 A)

JP 2010-28355 A

However, in the in-vehicle network system of Patent Document 1, it is possible to reduce the load on the network by performing arbitration processing such as reducing signals, but also reduce the signals required for the vehicle when performing the arbitration processing. There is a risk that.
The in-vehicle network system of Patent Document 1 is a difficult condition to predict that the execution timing of the process is “when the load on the network increases”. Therefore, the designer cannot reliably predict the timing at which the arbitration process occurs. As a result, the designer does not know whether communication is possible in a necessary state and in a necessary cycle. In order to incorporate the function of determining “when the network load increases” into the system, it is necessary to investigate the effects of the arbitration process in all situations that the vehicle faces.
For this reason, in the conventional in-vehicle network system, it is difficult to perform the arbitration process at an appropriate timing, and the network environment cannot be used efficiently.

  An object of the present invention is to realize an in-vehicle network system capable of efficiently using a network environment by optimizing the transmission cycle of communication messages of a plurality of electronic control devices connected to a network.

  The present invention provides an in-vehicle network system in which a plurality of electronic control devices mounted on a vehicle are connected via a communication line, wherein each of the plurality of electronic control devices includes vehicle state detection means for detecting a vehicle state, Communication control means for changing the transmission cycle of the communication message to a preset transmission cycle based on the vehicle state detected by the vehicle state detection means.

According to the present invention, the transmission cycle of the communication message can be optimized by changing the transmission cycle of the communication message to a preset transmission cycle based on the vehicle state.
For this reason, this invention can increase the transmission amount of the communication message required in a specific vehicle state, and can reduce the delay time of the communication message required in a specific vehicle state.
In addition, the present invention can efficiently use a network environment, and can finish communication with an external tool in a short time in rewriting the program of the electronic control device.

FIG. 1 is a system configuration diagram of an in-vehicle network system. (Example) FIG. 2 is a control flowchart of the in-vehicle network system. (Example)

  Embodiments of the present invention will be described below with reference to the drawings.

1 and 2 show an embodiment of the present invention. In FIG. 1, reference numeral 1 denotes an in-vehicle network system. In the in-vehicle network system 1, a plurality of electronic control devices 2-1 to 2-n mounted on a vehicle are connected via a communication line 3 of a LAN (CAN).
Each of the plurality of electronic control devices 2-1 to 2-n includes vehicle state detection means 4-1 to 4-n for detecting a vehicle state. Vehicle state input units 5-1 to 5-n are connected to the vehicle state detection units 4-1 to 4-n, respectively. Each vehicle state input means 5-1 to 5-n includes, for example, switches 1 to n and sensors 1 to n, and inputs a detection signal to each of the electronic control devices 2-1 to 2-n. Each vehicle state detection means 4-1 to 4-n detects the vehicle state by signals input from the respective vehicle state input means 5-1 to 5-n. Each of the plurality of electronic control devices 2-1 to 2-n transmits signals input from the vehicle state input units 5-1 to 5-n onto the communication line 3 as data for determining the vehicle state. Share.
Each of the plurality of electronic control devices 2-1 to 2-n includes transmission cycle storage means 6-1 to 6-n for storing a transmission cycle of a communication message set in advance based on the vehicle state, and a vehicle state. Communication control means 7-1 to 7-n for changing the transmission cycle of the communication message based on them. Each of the communication control means 7-1 to 7-n stores the communication stored in the transmission cycle storage means 6-1 to 6-n based on the vehicle state detected by the vehicle state detection means 4-1 to 4-n. With reference to the message transmission cycle, the communication message transmission cycle is changed to a preset transmission cycle.

About the change of the transmission period of the communication message based on the said vehicle state, a communication message is divided into the following groups by ID (communication frame), for example.
Grouping Group A: ID 001-200 {Signals related to vehicle running and safety (vehicle speed, engine speed, engine torque related signals, etc.)}
Group B: ID 201-300 {Vehicle specification information}
Group C: ID 301-400 {Failure diagnosis communication with a tester (external tool), etc.}

The communication messages of these A group, B group, and C group are in an ignition switch-on (hereinafter referred to as “IG-ON”) state and a vehicle traveling state (hereinafter referred to as “running” state). It is as follows.
・ IG-ON
Group A: Since the vehicle is stopped, high-speed communication is not required.
Group B: High-speed communication is desirable because it is desired to acquire (determine) information before the start of traveling.
Group C: High-speed communication is desirable in order to facilitate vehicle fault diagnosis and ECU programming (rewriting).
・ During traveling Group A: High speed communication is required to control the vehicle and safety.
Group B: It should have been confirmed before driving, and high-speed communication is unnecessary.
Group C: High-speed communication is not required during running because there is no failure diagnosis with an external tool or programming of the electronic control unit.

Thus, for the A group, the B group, and the C group, the change of the transmission cycle of the communication message based on the vehicle state is set as follows in each condition of IG-ON and traveling.
Group ID IG-ON Running A group ID 001-200 100ms 10ms
Group B ID 201-300 10ms 1000ms
Group C ID 301-400 10ms 500ms

  The transmission cycle of the communication message based on the vehicle state for the A group, the B group, and the C group set in this way is the transmission cycle storage units 6-1 to 6-6 of the plurality of electronic control devices 2-1 to 2-n. -N is stored as a transmission cycle change map for each ID of each communication message. The communication control units 7-1 to 7-n of the plurality of electronic control devices 2-1 to 2-n store the transmission cycle based on the vehicle state detected by the vehicle state detection units 4-1 to 4-n. The communication message transmission cycle change map stored in the means 6-1 to 6-n is referenced to change the communication message transmission cycle to a preset transmission cycle.

Next, the operation will be described.
As shown in FIG. 2, when the program for changing the transmission cycle starts (S01), the in-vehicle network system 1 determines whether the vehicle state detected by the vehicle state detection units 4-1 to 4-n has changed. Determination is made by the communication control means 7-1 to 7-n (S02).
When this determination (S02) is YES, the transmission cycle change map for each ID of each communication message stored in the transmission cycle storage means 6-1 to 6-n is referred to change to the transmission cycle corresponding to the vehicle state. (S03), and the program is ended (S04). If this determination (S02) is NO, the program is ended (S04).
In the change of the transmission cycle corresponding to the vehicle state (S03), for example, the communication message of group A ID 001-200 has a transmission cycle of 100 ms in IG-ON and a short transmission cycle of 10 ms during traveling. . The communication message of ID 201-300 in group B has a transmission cycle of 10 ms in ID-ON and a long transmission cycle of 1000 ms during traveling. The communication message of group 301 ID 301-400 has a transmission cycle of 10 ms in ID-ON and a long transmission cycle of 500 ms during traveling.

In this way, the in-vehicle network system 1 shortens the transmission cycle of the necessary signal messages according to each vehicle state and supplies many signal messages on the network, while the unnecessary signal message group of each vehicle state is provided. Increase the period and lower the network occupancy by this group. Thus, the in-vehicle network system 1 can optimize the transmission cycle of the communication message by changing the transmission cycle of the communication message based on the vehicle state.
For this reason, the in-vehicle network system 1 can supply more necessary signal messages to the network when necessary in a limited network environment, and can realize more reliable control. Therefore, the in-vehicle network system 1 can increase the transmission amount of communication messages necessary in a specific vehicle state, and can reduce the delay time of communication messages necessary in a specific vehicle state.
Moreover, the vehicle-mounted network system 1 can suppress the influence on communication with an external tool by lowering the network occupation ratio of each group in IG-ON (the engine is not started). Therefore, the in-vehicle network system 1 can efficiently use the network environment, and can finish communication with the external tool in a short time in rewriting the program of the electronic control device.

  In the above-described embodiment, the communication message is divided into A group, B group, and C group by ID (communication frame), and the change of the transmission cycle is set. Can also be set.

  In the above-described embodiment, the signal message transmission cycle is set on the condition that the vehicle state is IG-ON and traveling. You can also.

For example, depending on the electronic control device, when a failure occurs during the IG cycle from IG-ON to IG-OFF, even when the vehicle returns from the failure state, the fail-safe state continues until IG-OFF. Yes (ESP: Electronic Stability Program, etc.). Such electronic control devices usually require high-speed communication. However, after the failure is confirmed, even if the communication is performed at high speed, it is not accepted, so it is not necessary to perform communication at high speed.
Therefore, for the electronic control device that performs such an operation, the transmission cycle of the communication message can be optimized by setting the transmission cycle of the signal message to be changeable between the failure state and the non-failure state.

Also, for example, when the light is on, the light is off, and the day and night are distinguished, the signals necessary for light control (light irradiation direction (up / down / left / right) adjustment signals, etc.) Only high speed communication is required. However, when the light is turned off, a signal necessary for controlling the light is not necessary.
Therefore, with respect to the light control device, the transmission cycle of the communication message can be optimized by setting the transmission cycle of the signal message to be changeable between day and night.

Further, regarding the air temperature, it is necessary to communicate signals necessary for air conditioning control at high speed while the air conditioner is on, but it is not necessary to communicate signals necessary for air conditioning control at high speed while the air conditioner is off. .
Therefore, for the control device of the air conditioner, the transmission cycle of the communication message can be optimized by setting the transmission cycle of the signal message to be changeable between ON and OFF.
As for the weather, ON / OFF of the wiper device applies in the same way as ON / OFF of the air conditioner. Therefore, for the control device of the wiper device, the transmission cycle of the signal message is set to be changeable between ON and OFF. Thus, the transmission cycle of the communication message can be optimized.

  The present invention can optimize a communication message transmission cycle of a plurality of electronic control devices connected to a network to efficiently use a network environment, and is not limited to an in-vehicle network system. The present invention can be applied to a network system to which devices are connected.

DESCRIPTION OF SYMBOLS 1 In-vehicle network system 2-1 to 2-n Electronic controller 3 Communication line 4-1 to 4-n Vehicle state detection means 5-1 to 5-n Vehicle state input means 6-1 to 6-n Transmission period storage means 7-1 to 7-n Communication control means

Claims (1)

  In an in-vehicle network system in which a plurality of electronic control devices mounted on a vehicle are connected via a communication line, each of the plurality of electronic control devices includes a vehicle state detection unit that detects a vehicle state, and the vehicle state detection unit An in-vehicle network system comprising: a communication control unit that changes a transmission cycle of a communication message to a preset transmission cycle based on the vehicle state detected by the above.

Images