JPH10136465A - Vehicle data transmission system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve efficiency in the bus occupation rates of respective nodes on a network by providing a non-circulation node, plural circulation nodes connected to a bus and connection information sending means for sending node connection information showing the non-circulation node to all the nodes. SOLUTION: When the connection information sending means sends the node connection information showing the plural circulation nodes connected to the bus and the non-circulation node to all the nodes, the non-circulation node having no transmission right receives the node connection information. Namely, since the non-circulation node does not perform data transmission due to token passing but just receives data or node connection information, efficiency in the bus occupation rate can be improved. In a vehicle transmission system, for example, the circulation nodes comprises an engine control node 1a, mission control node 1b, brake control node 1c and output torque control node 1d. Besides, the non-circulation node is composed of a suspension control node 1d connected to a bus 3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plurality of nodes mounted on a vehicle connected to a bus, circulating a transmission right between the nodes in a predetermined order, and a node acquiring the transmission right being connected to the bus. The present invention relates to a vehicle data transmission system for transmitting data to a vehicle, and more particularly to a vehicle data transmission system for improving the efficiency of bus occupancy of data to be transmitted.

[0002]

2. Description of the Related Art In a vehicle such as an automobile, a plurality of electronic control nodes are connected to a common bus, and data is transmitted and received between the nodes. In this case, a token passing method is known in which the transmission right is circulated between the nodes in a predetermined order, and the node that has acquired the transmission right sends data to the bus.

In this token passing method, an address of a destination node is set to a value obtained by adding a value 1 to an address of the own node, and a transmission right transfer message is transmitted to a destination node adjacent to the own node.

[0004] By performing such a transmission right transfer message transmission processing for each node, the transmission right is circulated to each node in a predetermined order. Then, the node that has acquired the transmission right sends data to the bus, so that data can be transmitted and received between the nodes.

[0005] In addition, when a transmission right transfer destination message (hereinafter referred to as a transmission transfer destination message) and data are sequentially transmitted between a plurality of nodes of a conventional vehicle data transmission system using the token passing system. Is performed according to the flowchart shown in FIG.

Here, for example, a case in which nodes 1a to 1e are connected to a bus and node 1d transmits data to another node will be described.

First, it is determined whether the own node (node 1d) has received the transmission delegation message (step S101). If the own node has received the transmission delegation message, the transmission delegation address is set to the next address value. (Step S103).

Next, if the processing is to be continued (step S105), data is received from the network (bus) (step S107), and it is determined whether necessary data should be transmitted to the node 1a based on the received data. (Step S109). If the necessary data is to be transmitted to the node 1a, the necessary data is transmitted to the node 1a (step S111).

Next, it is determined whether necessary data should be transmitted to the node 1b based on the received data (step S113). If the necessary data should be transmitted to the node 1b, the necessary data is transmitted to the node 1b (step S115).

[0010] Similarly, the necessary data is transmitted to the node 1c (steps S117, 119), and the required data is transmitted to the node 1e (step S117).
121, 123), and returns to the process of step S101.

As described above, in the conventional token passing system, each node has a transmission right, and the node that has acquired the transmission right transmits necessary data to another node via the bus.

[0012]

However, among a plurality of nodes constituting the token passing system, there are simple nodes which are inexpensive and which only need to have a function of receiving data. The simple node is caused to participate in token passing, and the simple node has a transmission right like other nodes and transmits data.

That is, the simple node occupies the bus for transmitting data, although it is sufficient to receive the data. For this reason, the efficiency of the bus occupancy of other nodes cannot be improved.

An object of the present invention is to provide a vehicle data transmission system capable of improving the efficiency of the bus occupancy of each node on a network.

[0015]

The present invention employs the following means in order to solve the above-mentioned problems. The invention according to claim 1 includes a transfer destination setting means for setting a transfer right transfer destination node, and a transmission / reception means for transmitting a transmission right transfer message to the transmission right transfer destination node set by the transfer right setting node. Comprising a plurality of circulating nodes connected to, circulating the transmission right between each circulating node in a predetermined order,
A vehicle data transmission system in which a circulating node that has acquired a transmission right sends data to the bus, wherein the at least one non-circulating node is connected to the bus and receives data or information without the transmission right; The gist of the present invention is to provide a connection information sending unit that sends node connection information indicating the plurality of circulating nodes connected to a bus and the one or more acyclic nodes to all nodes.

According to the present invention, when the connection information sending means sends node connection information indicating a plurality of circulating nodes and one or more non-circulating nodes connected to the bus to all nodes, the connection information sending means has no transmission right. The above non-circulating nodes receive the node connection information.

That is, the non-circulating node does not perform data transmission by token passing but only receives data or node connection information, so that the bus occupancy can be made more efficient.

According to a second aspect of the present invention, the non-circular node comprises:
The gist of the present invention is to include a data transmission determining unit that determines whether to transmit the data of the own node to each of the circulating nodes with reference to the node connection information received from the connection information transmitting unit.

According to the present invention, the data transmission determining means of the non-circular node refers to the node connection information received from the connection information transmitting means to determine whether to transmit the data of the own node to each of the circular nodes. Therefore, the node to be transmitted can be determined with reference to the node connection information, and the bus occupancy can be made more efficient.

The invention of claim 3 is characterized in that the transfer destination setting means sets a transfer right transfer destination node with reference to the node connection information.

According to the invention, the delegation destination setting means sets the transmission right delegation node with reference to the node connection information, and the transmission / reception means sets the transmission right delegation destination node set by the delegation destination setting means. To send a transmission right transfer message. That is, since the transmission delegation destination message is transferred only to the node currently connected to the bus, the efficiency of the bus occupancy can be improved.

[0022] In the invention of claim 4, it is essential that the connection information sending means is provided in one of the plurality of circulating nodes.

According to a fifth aspect of the present invention, when one of the plurality of circulation nodes changes the node connected to the bus by adding or decreasing, the changed node connection information at that time is changed. The gist is to transmit to all nodes.

According to the present invention, one of the plurality of nodes
One of the nodes sends the changed node connection information to all the nodes when the node connected to the bus is changed by addition or reduction, so that the transmission delegation destination is changed according to the changed node connection information. Node can be determined,
In addition, a non-circulating node can also determine a node to be transmitted according to the changed node connection information, and can further increase the efficiency of bus occupancy.

[0025]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a vehicle data transmission system according to the present invention will be described below with reference to the drawings. FIG. 1 shows a configuration diagram of an embodiment of a vehicle data transmission system of the present invention.

In the vehicle transmission system shown in FIG. 1, an engine control node 1a, a mission control node 1b, a brake control node 1c, and an output torque control node 1e are connected to a bus 3 in the network.

These control nodes transmit and receive necessary data between the nodes by the token passing method. That is, the transmission right is circulated among the nodes 1a to 1c and 1e in a predetermined order, and the node which has acquired the transmission right sends the data to the bus 3.

The engine control node 1a, the mission control node 1b, the brake control node 1c, and the output torque control node 1e constitute a circulation node.

Further, a suspension control node 1d, which is a simple node, is connected to the bus 3, and this suspension control node 1d does not participate in the token passing method, but forms a non-circulation node. Note that the first control node 1f exists without being connected to the bus 3. Also,
Two or more non-circulating nodes may be connected to the bus 3.

The engine control node 1a controls the operation of the engine according to the driver's operation of the accelerator pedal or the like. The mission control node 1b controls the automatic transmission according to the driving state of the vehicle.

The brake control node 1c performs brake control by detecting a locked state of the wheels. The suspension control node 1d controls the suspension according to the driving state of the vehicle. Output torque control node 1
e detects the slip state of the drive wheels of the vehicle and controls the output torque of the engine.

The engine control node 1a includes a CPU (central processing unit) 11a, a transmitting / receiving unit 21a, a transfer destination setting unit 23
a, a memory 25a, and a data transmission determination unit 27a.

The engine control node 1a is connected to a sensor 31a provided in each part of the vehicle for detecting a running state and an actuator 41a.

Although only one sensor 31a is shown in FIG. 1, it is assumed that a plurality of sensors 31a are actually provided. The CPU 11a drives the actuator 41a based on a detection signal from the sensor 31a.

The engine control node 1a, which is the master node, stores state information indicating the state of the node on the bus 3 in the memory 25a. The status information indicating the status of the nodes on the bus 3 includes, for example, first node connection information, second node connection information, node remote information, and the like, which will be described later.

The first node connection information is information of a node connected (optionally mounted) on the bus 3, and here, as shown in FIG.
a, 1b, 1c, 1d, and 1e correspond.

The second node connection information is information on the nodes actually present on the bus 3 (option mounted and non-mounted), and here, as shown in FIG. 1a, 1b, 1c, 1d, 1e, 1f
Is applicable.

The remote information is, for example, information indicating the transmission order, and the transmission order information includes the nodes 1a, 1
The order is b, 1c, 1e.

The first control node 1f is connected to the bus 3
Is connected, the first control node 1f is added to the node connection information. The memory 25a stores transmission data.

The delegation destination setting unit 23a sets the delegation destination node of the transmission right by the address of the delegation destination node, and sets the delegation destination node by incrementing the address of the delegation destination node.

Each node may have a table storing the addresses of the preceding node, its own node, the next node, and the like, and the circulating order may be determined with reference to this table.

The data transmission judging section 27a includes a memory 25a
It is determined whether or not data should be sent to each node with reference to the state information stored in.

The transmission / reception unit 21a is provided with the delegation destination setting unit 23
The transmission right delegation message is transmitted to the transmission right delegation destination node set by a, and when the data transmission determining unit 27a determines that the data should be transmitted to the node, the data is transmitted to the node. Transmitting / receiving unit 21a
When a transfer right transfer message is received from the preceding node, the transfer destination setting unit 23a sets the next transfer destination node.

Transmission / reception unit 2 of the engine control node 1a
1a transmits the status information stored in the memory 25a to all the control nodes 1b, 1c, 1d, 1 connected to the bus 3.
e.

When a node connected to the bus 3 is changed by addition or reduction, the transmission / reception unit 21a of the engine control node 1a transmits the changed node connection information at that time to all the nodes connected to the bus 3. To the control node.

The transmission control node 1b, the brake control node 1c, and the output torque control node 1e have substantially the same configuration as that of the engine control node 1a.

The suspension control node 1d has a CPU
11d, a transmission / reception unit 21d, a memory 25d, and a data transmission determination unit 27d. The suspension control node 1d includes a sensor 3 provided at each part of the vehicle to detect a running state.
1d, the actuator 41d is connected.

Since the suspension control node 1d is a non-circular node that does not have the transmission right and receives data or information, it does not have a transfer destination setting unit. In other words, the suspension control node 1d is a node that is inexpensive and cannot hold communication network software.
No transmission request is made, and only status information is received from engine control node 1a.

The transmission / reception unit 21d is connected to the engine control node 1
Receive status information from a. The memory 25d is a transmission / reception unit 2.
The state information received in 1d is stored, and the own data is stored.

The data transmission judging section 27d includes a memory 25d
It is determined whether or not its own data should be sent to each control node with reference to the state information stored in. The transmission / reception unit 21d transmits its own data to the control node when the data transmission determination unit 27a determines that the data should be transmitted to the control node.

FIG. 2 shows the format of a data frame according to the embodiment. In FIG. 2, the data frame includes an SOM indicating the start of a message, a transfer destination address indicating an address of a transfer right transfer destination node, a transmission source address, data, an error detection character string CRC, reception acknowledgment information, and an end of the message. EOM shown.

The transfer destination address may be set to a value of 0 to 3 corresponding to each of the control nodes.

The data includes a data byte length, a data identifier, and information to be transmitted. The reception acknowledgment information includes reception acknowledgment information from a node that has successfully received data and reception acknowledgment information from a node that has normally received a transmission right. The transfer destination address is obtained from the transfer destination setting unit 23a.

Next, the operation of the embodiment configured as described above will be described with reference to the flowcharts shown in FIGS. Here, for example, in the circulating node, the transmission right is circulated in the order of the engine control node 1a, the mission control node 1b, the brake control node 1c, and the output torque control node 1e.

First, the transmission / reception unit 21a of the engine control node 1a, which is the master control node, uses the node connection information indicating the node currently connected to the bus 3 as the status information indicating the status of the node on the bus 3, for example. Is received from the external device. "1a, 1b, 1c, 1d, 1e" Then, the node addresses “1a, 1b, 1c, 1” are stored in the memory 25a of the engine control node 1a.
d, 1e "is stored.

Next, the transmission / reception unit 21a of the engine control node 1a transmits the node address stored in the memory 25a to all the control nodes 1b, 1c,
1d and 1e. Then, the control nodes 1b, 1
Also in c and 1e, the node address is received and stored in its own memory.

Next, the processing of the suspension control node 1d, which is a simple node, will be described with reference to the flowchart shown in FIG. First, when the transmission / reception unit 21d receives state information from the engine control node 1a on the network (step S11), the received state information is stored in the memory 25d (step S13).

If the processing is to be continued (step S15), the data transmission determining unit 27d
The presence / absence of necessary data to the engine control node 1a is determined with reference to the state information stored in the
17).

As the status information, for example, node addresses “1a, 1b, 1c, 1d, 1e” which are node connection information.
, And since the engine control node 1 a is connected to the bus 3, the transmission / reception unit 21 d
The necessary data is transmitted to a (step S19).

Next, the data transmission determination unit 27d refers to the state information and transmits the required data to the mission control node 1
It is determined whether there is a transmission to b (step S21). Since the mission control node 1b is connected to the bus 3,
The transmission / reception unit 21d transmits necessary data to the mission control node 1b (Step S23).

Further, the data transmission judging section 27d refers to the state information and outputs the necessary data of the brake control node 1
It is determined whether or not there is a transmission to c (step S25). Since the brake control node 1c is connected to the bus 3, the transmission / reception unit 21d transmits necessary data to the brake control node 1c (Step S27).

Finally, the data transmission determining section 27d refers to the state information and determines whether or not necessary data is transmitted to the output torque control node 1e (step S29). Since the output torque control node 1e is connected to the bus 3, the transmission / reception unit 21d transmits necessary data to the output torque control node 1e (Step S31). When these processes are completed, the process returns to the step S11.

As described above, the suspension control node 1d, which is a non-circulating node, does not transmit data by token passing, but only receives data or node connection information. However, other circulating nodes can occupy the bus 3, and the bus occupancy can be made more efficient.

Further, the data transmission determination section 27d of the suspension control node 1d determines whether or not to transmit the data of its own node to each circulation node with reference to the node connection information received from the engine control node 1a. The node to be transmitted can be determined with reference to the node connection information. That is, since there is no need to transfer necessary data to unnecessary control nodes, the efficiency of bus occupancy can be improved.

Next, according to the flow chart shown in FIG. 4, the circulating node, for example, the brake control node 1c
Will be described.

First, the mission control node 1b
, "1c (brake control node address)" as the transfer destination address, and "1b
(The address of the mission control node) ", and transfers it to the brake control node 1c.

Then, the transmission / reception unit 21c of the brake control node 1c sends the transmission transfer destination message (here, the transfer destination address “1”) from the mission control node 1b to the transmission transfer destination message.
c ”) is determined (step 4).
1).

The brake control node 1c receives the transfer destination address "1c" and the transmission source address "1b" and obtains the transmission right. Then, the transfer destination setting unit 23c in the brake control node 1c sets the transfer destination address to the next transfer destination address.
1e (address of output torque control node) "(step S43).

When the processing is to be continued (step S45), data (state information) is received from the bus 3 on the network (step S47), and the state information is stored in the memory 25c.

The data transmission determining unit 27c is provided in the memory 25c
The presence / absence of necessary data to the engine control node 1a is determined with reference to the state information stored in the
49).

As the state information, for example, node addresses “1a, 1b, 1c, 1d, 1e” which are node connection information
, The engine control node 1a is connected to the bus 3, so that the transmission / reception unit 21c
The necessary data is transmitted to a (step S51).

Next, the data transmission determining unit 27c refers to the status information and transmits the required data to the mission control node 1.
It is determined whether there is a transmission to b (step S53). Since the mission control node 1b is connected to the bus 3,
The transmission / reception unit 21c transmits necessary data to the mission control node 1b (Step S55).

Further, the data transmission determining section 27c refers to the state information and determines whether or not the necessary data has been transmitted to the output torque control node 1e (step S57). Since the output torque control node 1e is connected to the bus 3, the transmission / reception unit 21c transmits necessary data to the output torque control node 1e (Step S59). When these processes have been completed, the process returns to the step S41.

As described above, the engine control node 1a, which is the master node, sends out the node connection information indicating all the nodes connected to the bus 3 to all the nodes connected to the bus 3.

Then, the delegation destination setting units of all the other nodes determine the required destination node based on the node connection information and the transmission order, and the transmission / reception unit sends out the transmission data. Messages are not transferred on the bus 3 unnecessarily. Therefore, the efficiency of the bus occupancy of each node on the network can be improved.

When the first control node 1f shown in FIG. 1 is additionally connected to the bus 3, for example, the node address "node connection information indicating the first control node 1f"
1f "is sent from the outside to the engine control node 1a. Then, the node address" 1 "which is the node connection information.
a, 1b, 1c, 1d, 1e, 1f "are stored in the memory 25a.

The transmission / reception unit 21a of the engine control node 1a transmits the node address "1a, 1b, 1c, 1d, 1" which is the node connection information stored in the memory 25a.
e, 1f "is connected to all the control nodes 1 connected to the bus 3.
b, 1c, 1d, 1e, 1f. Then, also in the control nodes 1b to 1f, the node connection information is stored in each memory.

Each node connected to the bus 3 determines a transmission destination node or a node to which data is to be transmitted, based on the node connection information stored in the memory and the transmission order. That is, the transmission delegation node can be determined according to the changed node connection information, and the suspension control node 1d, which is a non-circulating node, can also determine the node to be transmitted according to the changed node connection information. Thus, the efficiency of the bus occupancy can be improved.

Further, another control node may be additionally connected to the bus 3. Conversely, a certain node may be separated from the bus 3. in this way,
When a node is changed by addition or reduction, the contents of the memory 25a may be rewritten according to the change.

For example, when the mission control node 1b is disconnected from the bus 3, the node addresses of the memory 25a are "1a, 1c, 1d, 1e, 1f".
In this case, the transfer destination setting unit 23 of the engine control node 1a
When a sets the next mission control node 1b for its own node 1a, this mission control node 1b is not in the memory 25a, so the control node is incremented and the next brake control node 1c is set.

This brake control node 1c is stored in the memory 25
a. Therefore, the transmission / reception unit 21a of the engine control node 1a sends the transmission delegation destination message to the brake control node 1c as the transmission delegation destination node, so that the brake control node 1c acquires the transmission right.

The present invention is not limited to the embodiment described above. In the embodiment, the non-circulating node is the suspension control node 1d. However, if the node is inexpensive and cannot hold the communication network software, the other control nodes 1a, 1b, 1c, and
It is not necessary for any of the control nodes 1e to participate in the token passing method as a non-circular node.

Further, the engine control node 1a, as a master control node, sends out status information to all the nodes connected to the bus 3, but any one of the mission control node 1b, the brake control node 1c, and the output torque control node 1e. May be the master control node.

[0084]

According to the present invention, when the connection information sending means sends node connection information indicating a plurality of circulating nodes and one or more non-circulating nodes connected to the bus to all the nodes, it has a transmission right. One or more acyclic nodes receive the node connection information. That is, the non-circulating node does not perform data transmission by token passing but only receives data or node connection information, so that the bus occupancy can be made more efficient.

The data transmission determining means of the non-circular node refers to the node connection information received from the connection information transmitting means to determine whether or not to transmit the data of the own node to each circulating node. The node to be transmitted can be determined by referring to the information, and the bus occupancy can be made more efficient.

Further, the delegation destination setting means sets the transmission right delegation node with reference to the node connection information, and the transmission / reception means transmits the transmission right to the transmission right delegation destination node set by the delegation destination setting means. Send a delegation message. That is,
Since the transmission transfer destination message is transferred only to the node currently connected to the bus, the efficiency of the bus occupancy can be improved.

Further, one of the plurality of nodes transmits the changed node connection information at that time to all nodes when the number of nodes connected to the bus is changed by addition or reduction. The transmission delegation destination node can be determined according to the changed node connection information, the node to be transmitted can also be determined according to the changed node connection information, and the efficiency of bus occupancy can be improved. .

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing an embodiment of a vehicle data transmission system of the present invention.

FIG. 2 is a diagram showing a format of a data frame.

FIG. 3 is a flowchart illustrating an operation of a suspension control node that is a non-circulating node.

FIG. 4 is a flowchart showing the operation of each cyclic node.

FIG. 5 is a flowchart showing the operation of the conventional vehicle data transmission system.

[Explanation of symbols]

 1a Engine control node 1b Mission control node 1c Brake control node 1d Suspension control node 1e Output torque control node 3 Bus 11a, 11d CPU 21a, 21d Transmission / reception unit 23a Delegation destination setting unit 25a, 25d Memory 27a, 27d Data transmission determination unit 31a, 31d sensor 41a, 41d actuator

Claims (5)

[Claims] 1. A delegation destination setting means for setting a transmission right delegation destination node, a transmission / reception means for transmitting a transmission right delegation message to the transmission right delegation destination node set by the delegation destination setting means, and connected to a bus. In the vehicle data transmission system comprising a plurality of circulation nodes, the transmission right is circulated among the circulation nodes in a predetermined order, and the circulation node that has acquired the transmission right sends data to the bus, One or more acyclic nodes that are connected and receive data or information without the transmission right, and node connection information indicating the plurality of cyclic nodes and the one or more acyclic nodes connected to the bus And a connection information sending means for sending the connection information to all nodes. 2. The non-circular node includes a data transmission determining unit that determines whether to transmit data of the own node to each of the circulating nodes with reference to the node connection information received from the connection information transmitting unit. The vehicle data transmission system according to claim 1, wherein: 3. The vehicle data transmission system according to claim 1, wherein the delegation destination setting unit sets a transmission right delegation destination node with reference to the node connection information. 4. The vehicle data transmission system according to claim 1, wherein the connection information sending unit is provided in one of the plurality of circulation nodes. 5. One of the plurality of circulating nodes, when a node connected to the bus changes due to addition or reduction, sends the changed node connection information at that time to all nodes. The vehicle data transmission system according to claim 4, wherein: