JP4548260B2 - Vehicle communication system - Google Patents

Description

  The present invention relates to a vehicle communication system that transmits and receives data between a plurality of control units mounted on a vehicle.

  As more and more control units that electronically control onboard devices are adopted, there is an increasing demand for sharing data among the control units and performing distributed control and cooperative control in each control unit. For example, in a vehicle, each control unit is networked according to the classification of body systems such as seats and doors, powertrain systems such as engines and electronic throttles, and information systems such as navigation, VICS, and ETC. It has been considered to connect via a gateway unit capable of relaying.

  Here, when the ignition switch is turned off and the vehicle is parked, it is not necessary to perform basic functions as a vehicle. Transition to operation mode. This low power consumption operation mode means that the operation frequency is lowered than the normal operation mode, the operation is stopped until a predetermined trigger signal is input, or the operation is completely stopped. This is an operation mode in which power consumption in each control unit can be reduced.

  When each control unit is networked as described above, because of the cooperative operation of each control unit, if the operation mode of one control unit is the high power consumption operation mode, the other control units will The operation mode is also set to the high power consumption operation mode. When each control unit is divided into a plurality of groups and networked, the gateway unit may manage the operation modes of the control units belonging to the plurality of networks. That is, when a plurality of control units that need to transmit and receive data are divided into different networks, upon receiving data indicating that the power consumption operation mode is from one control unit, the gateway unit Mode management is performed to operate in the high power consumption operation mode. In order to avoid complicated operation mode management, the gateway unit normally does not target individual control units but manages operation modes in units of networks.

  In such a communication system having only one gateway unit, the operation mode of each network can be collectively managed by the gateway unit, and the operation mode can be shifted between the high power consumption operation mode and the low power consumption operation mode. It can be done smoothly.

  However, the number of control units to be networked and the amount of communication data are steadily increasing, and it is conceivable that a single gateway unit cannot cope with an increase in the scale of the network. That is, the number of control units connected to one network is naturally limited from the viewpoint of data transmission / reception speed between control units. As the number of networks increases, it becomes difficult to cover communication between the networks with one gateway unit. For this reason, it is conceivable to connect a plurality of networks via a plurality of gateway units.

  In this case, one network is connected to a plurality of networks via a plurality of gateway units, and it is conceivable that a malfunction occurs in the operation mode management due to this configuration. That is, when the gateway unit receives the high power consumption operation mode data from any of the control units, the gateway unit transmits the high power consumption operation mode data to all the networks connected for data relay. Thereby, the operation mode of all the networks connected to the gateway unit is managed in the high power consumption operation mode. Therefore, as described above, when a plurality of gateway units are connected to one network, a situation may occur in which high power consumption operation mode data is exchanged between the gateway units. As a result, each control unit cannot shift to the low power consumption operation mode.

  In order to solve such problems, the present applicant has applied for Japanese Patent Application No. 2005-141550. In the vehicular communication system according to this application, when the gateway unit receives data related to the operation mode, the gateway unit does not transmit the data to the network including the unit that transmitted the data related to the operation mode. As a result, it is possible to avoid occurrence of a situation in which data regarding the high power consumption operation mode is exchanged between the gateway units, and to shift each unit to the low power consumption operation mode.

  However, when configured as described above, the transition timing to the low power consumption operation mode in the communication system is the permission timing by any unit that finally permits the transition from the high power consumption operation mode to the low power consumption operation mode. Will depend. That is, the transition timing to the low power consumption operation mode cannot be managed as the entire communication system.

  The present invention has been made in view of the above points, and provides a vehicle communication system capable of managing the transition timing from the high power consumption operation mode to the low power consumption operation mode as the entire system. Objective.

In order to achieve the above object, the vehicle communication system according to claim 1 divides a plurality of control units mounted on the vehicle into at least three or more groups and performs data communication for the control units for each group. Connected to each other via a communication line for communication, and connected to a plurality of networks by providing a plurality of gateway units that connect the plurality of networks and relay data. Data can be sent and received between control units,
The control unit has a high power consumption operation mode and a low power consumption operation mode as operation modes, and transmits operation mode data related to the operation mode to other units in the network to which the control unit is connected via the communication line. And, when the high power consumption operation mode data is received from another unit, its own operation mode is set to the high power consumption operation mode.
One gateway unit of a plurality of gateway units, as a centralized management gateway unit, receives data indicating that it can shift to a low power consumption operation mode from all connected units until a predetermined condition is satisfied , Send high power consumption operation mode data to a plurality of networks connected to itself, and when a predetermined condition is established, send low power consumption operation mode data,
When other gateway units of multiple gateway units receive operation mode data from a unit connected to one of the multiple networks to which they are connected, they connect to other networks except that one network The operation mode data is transmitted to the selected unit.

  As described above, in the vehicle communication system according to the first aspect, one gateway unit of the plurality of gateway units can shift from all the connected units to the low power consumption operation mode as a centralized management gateway unit. Even if the data is received, the high power consumption operation mode data is transmitted to a plurality of connected networks until the predetermined condition is satisfied, and the low power consumption operation is performed when the predetermined condition is satisfied. Send mode data. For this reason, the centralized management gateway unit can manage the transition timing of the entire communication system from the high power consumption operation mode to the low power consumption operation mode based on the establishment of a predetermined condition.

  The other gateway units of the plurality of gateway units transmit the operation mode data only to the remaining networks excluding the network to which the unit that transmitted the operation mode data belongs. For this reason, it is possible to avoid a situation where high power consumption operation mode data is exchanged between gateway units connected to the same network.

  As described in claim 2, when the centralized management gateway unit reaches a predetermined time after receiving data indicating that it can shift to the low power consumption operation mode from all connected units. It can be configured to determine that a predetermined condition is satisfied.

  For example, even when a certain control unit finishes control of the corresponding control target device and determines that the transition to the low power consumption operation mode is possible, it may be necessary to resume control immediately after that. is there. In such a case, if the entire communication system has been shifted to the low power consumption operation mode, it is necessary to take measures to return each control unit to the high power consumption operation mode. It is conceivable that this cannot be done.

  On the other hand, in the system according to claim 2, even if the centralized management gateway unit receives data indicating that it can shift to the low power consumption operation mode from all the units, the low power operation mode is immediately performed. Instead of permitting the transition to, the time elapsed from that point is counted, and when the elapsed time reaches a predetermined time, low power consumption operation mode data is output to each unit, and the low power consumption operation Switch to mode. In this way, it is possible to prevent the entire communication system from being shifted to the low power consumption operation mode, so that it becomes possible to quickly respond when the control needs to be resumed.

  Further, as described in claim 3, the centralized management gateway unit shifts all control units to the low power consumption operation mode based on the detection signal from the detection means for detecting the vehicle state. It may be configured to determine that a predetermined condition is satisfied when it is considered to be a state to be made.

  For example, even when the ignition switch is turned off and the engine of the vehicle is stopped, there is a possibility that various control target devices mounted on the vehicle need to be operated in a state where an occupant is on the vehicle. There is. On the contrary, in the state where all the occupants get out of the vehicle and the vehicle is parked, it is not necessary to frequently operate various devices to be controlled. Therefore, for example, when it is detected as a vehicle state that an occupant is in the vehicle, the transition to the low power consumption operation mode is prohibited, and when all the occupants get out of the vehicle, all control units are By shifting to the low power consumption operation mode, it is possible to shift to the low power consumption operation mode at an appropriate timing.

  As described in claim 4, when the vehicle engine is stopped and the high power consumption operation mode data is received from the predetermined control unit, the centralized management gateway unit is associated with the control unit. Alternatively, high power consumption operation mode data may be transmitted to a specific network, and low power consumption operation mode data may be transmitted to another network.

  When the vehicle engine is stopped, the in-vehicle battery is not charged. Therefore, it is preferable to suppress the power consumption of the in-vehicle battery as much as possible. For this reason, when the vehicle engine is stopped, with respect to a predetermined control unit that operates in the high power consumption operation mode, a specific network is configured by collecting control units that must always perform data communication with the control unit, When the high power consumption operation mode data is received from the predetermined control unit, the high power consumption operation mode data is transmitted only to the specific network. Thereby, since the control unit connected to the other network is maintained in the low power consumption operation mode, the power consumption can be suppressed.

  According to a fifth aspect of the present invention, the control unit is in the low power consumption operation mode while the ignition switch of the vehicle is turned off, and enters the high power consumption operation mode when a predetermined activation condition is satisfied. Can be configured to work. This is because the vehicle is stopped while the ignition switch of the vehicle is turned off, and basically it is not necessary to cause the control unit for controlling various in-vehicle devices to function in the same manner as when the vehicle is running. Therefore, it is preferable to reduce the power consumption by shifting the operation mode of the control unit to the low power consumption operation mode in accordance with the ignition switch being turned off.

  However, for at least some control units, for example, it may be preferable to wake up on the condition that a certain time has elapsed and operate in the high power consumption operation mode (normal operation mode). For example, in the case of a so-called smart key system that can release a door lock without using a mechanical key by mutual communication with a portable key, a question signal is periodically sent from a smart key ECU as a control unit when the vehicle stops. This is because it is necessary to perform processing such as transmission and reception of a response signal from the portable key.

  As described in claim 6, the other gateway units also have a high power consumption operation mode and a low power consumption operation mode as operation modes, and all control units in the network to which the gateway unit is connected have low power consumption. When entering the consumption operation mode, the other gateway units are preferably in the low power consumption operation mode. When all the control units in the network are in the low power consumption operation mode, data to be relayed quickly is not generated. For this reason, it is preferable that other gateway units also shift to the low power consumption operation mode to reduce power consumption.

  However, as described in claim 7, when another gateway unit also has a function as a control unit that controls a predetermined control target device in the vehicle, the operation mode of the control unit is low power. It is preferable to shift the operation mode to the low power consumption operation mode on condition that the operation mode can be set.

  As described in claim 8, if the unit that transmitted the operation mode data is a control unit, the other gateway unit also transmits the data regarding the operation mode to the network including the control unit. For example, the operation mode data may not be transmitted to the network including the gateway unit. If the transmission source of the operation mode data is the control unit, even if the operation mode data is transmitted to all networks to which other gateway units are connected, the above-described high power consumption operation mode between the gateway units This is because a situation in which data is exchanged does not occur.

(First embodiment)
FIG. 1 is a block diagram showing an overall configuration of a vehicle communication system according to a first embodiment of the present invention. The vehicle communication system includes a network configuration in which various control units that electronically control onboard devices are connected to each other via a communication line and a gateway unit. It controls various power train equipment such as engines, transmissions and brakes, body equipment such as air conditioners, seats and door locks, information systems such as navigation, ETC and radio, and safety equipment such as airbags. The control unit can be the target of networking.

  These control units need to perform various calculations at high speed and optimally control the on-vehicle equipment while the ignition switch is on. For this reason, the operation mode of each unit is basically set to the normal operation mode (high power consumption operation mode). On the other hand, when the ignition switch is turned off and the vehicle is parked, it is not necessary to perform the basic functions of the vehicle, so that each control unit is shifted to the low power consumption operation mode. The In the low power consumption operation mode, the operation frequency is lowered than in the normal operation mode, the operation is stopped until a predetermined trigger signal is input from an external circuit or the like, or the operation is completely stopped. Thereby, the power consumption in each control unit can be reduced.

  In the present embodiment, among such control units, when a predetermined wake-up condition is established in order to execute control processing for the on-vehicle equipment even when the vehicle is stopped, the low power consumption operation mode is changed to the normal operation mode. A network configuration for a control unit that shifts to the normal operation mode and another control unit connected to the network that needs to shift to the normal operation mode will be described.

  Specific examples of such a control unit include, for example, various control units (ECUs) in a so-called smart key system that releases a door lock without using a mechanical key by mutual communication between a portable key and a smart key ECU. Is mentioned. In the smart key system, the smart key ECU is switched from the low power consumption operation mode to the normal operation mode every time a predetermined time elapses as a wake-up condition. Instructs reception of response signal. Since the response signal is returned when the portable key held by the user receives the question signal, it can be recognized that the user is approaching the vehicle by receiving the response signal.

  Based on the response signal, the smart key ECU determines whether or not the holder of the portable key is an authorized user. The determination result is transmitted to each door ECU, and the state of the door is controlled to each state of lock, unlock standby, or unlock. For example, when the holder of the portable key is a legitimate user and the user is approaching the vehicle, each door ECU indicates the state of each door of the vehicle, and the user sets a switch provided on the door handle. It is controlled to the unlock standby state where the door is unlocked by operating. As described above, since the smart key ECU and each door ECU need to operate in a coordinated manner, the operation mode of each door ECU is a low power consumption operation in accordance with the transition to the normal operation mode of the smart key ECU. The mode is switched to the normal operation mode.

  Further, depending on the vehicle, an immobilizer ECU is provided. The immobilizer ECU communicates with the smart key ECU when the engine is started by the user. Based on the communication result, the engine is permitted or prohibited. Switch. In other words, the immobilizer ECU permits the engine to start only when the smart key ECU determines that the user is an authorized user. Therefore, the operation mode of the immobilizer ECU is also preferably switched from the low power consumption operation mode to the normal operation mode in accordance with the transition of the smart key ECU to the normal operation mode. Alternatively, the immobilizer ECU enters the normal operation mode by the engine starting operation, and the smart key ECU can be switched to the normal operation mode using the communication from the immobilizer ECU as a trigger.

  As described above, some control units of vehicle-mounted devices are set in the normal operation mode when a predetermined wake-up condition is satisfied even when the vehicle is stopped, or when other control units are shifted to the normal operation mode. Some control units can be switched from the low power consumption operation mode to the normal operation mode. In the network configuration according to the present embodiment, such control units are divided into at least three or more groups, and each group is connected to each other via a data communication communication line to form a plurality of networks. . Further, the plurality of networks are connected via a plurality of gateway units for data relay, and data can be transmitted and received between control units connected to the plurality of networks.

  The reason for forming the plurality of networks by dividing the control units into at least three or more groups is to reduce the waiting time for data transmission of each control unit by reducing the number of control units connected to each network. This is because if the wiring length in forming the network is increased, the waveform of the transmission signal is likely to be disturbed, so that the wiring length is shortened.

  In the example shown in FIG. 1, the control units A to D are connected to the first network, the control units E to H are connected to the second network, the control units I to L are connected to the third network, and the fourth Control units M to P are connected to the network. A gateway (GW) unit X is connected between the first network and the second network, and a gateway unit Y, which is a centralized management gateway unit, is connected between the second network and the third network. A gateway (GW) unit Z is connected between the third network and the fourth network.

  In the following description, a case where a known token passing method is employed as a communication protocol in the above-described network configuration will be described. However, various known protocols such as CSMA / CR (carrier sense multiple access with collision resolution) method and TDMA (time division multiple access) method other than the token passing method may be adopted as the communication protocol. Further, by providing the gateway unit with a protocol conversion function, it is possible to adopt different communication protocols in each network.

  FIG. 2A shows an example of a communication data structure used when data is transmitted / received between control units in order to perform distributed control and cooperative control between the control units. As shown in FIG. 2A, the communication data has a header field and a data field, and a data body is written in the data field. The header field includes an ID that is a code unique to each unit and a data length code (DLC) that indicates the length of the data body.

  FIG. 2B shows an example of a mode management data structure for managing the operation mode of the control unit. As shown in FIG. 2B, the mode management data has an addressing field, a control field, and a data field. However, in the mode management data, data is not transmitted using the data field, and this data field is provided for convenience in order to match the data length with the communication data of FIG.

  The addressing field includes an ID indicating a data transmission source unit, a DLC indicating the length of mode management data, and a destination ID (DID) indicating a unit that passes a token that is a data transmission right. Note that communication data and mode management data can be distinguished by making their IDs different. The control field includes an operation code (OpCode) indicating an operation mode. This operation code includes an indicator code Ind and an acknowledge code Ack.

  The indicator code Ind indicates whether or not the control unit itself that transmits the mode management data can shift to the low power consumption operation mode without performing a predetermined control process. For example, the low power consumption operation mode If the transition is possible, the indicator code Ind = 1 is output. If the transition is not possible, the indicator code Ind = 0 is output. The acknowledge code Ack instructs all control units in the network to permit / prohibit the transition to the low power consumption operation mode. For example, when the transition is permitted, the acknowledge code Ack = 1 and the transition prohibition are prohibited. In this case, the acknowledge code Ack = 0 is output.

  Each control unit transmits the above-described communication data and mode management data to the control unit and the gateway unit in the network at the timing when the control unit obtains the right to transmit data (token). When the control unit in the network receives the communication data, it determines from the ID indicating the data transmission source unit whether the data is necessary for its own control, and holds only the necessary data. Furthermore, based on the mode management data, the operation mode of the other control unit is held, and it is determined whether or not it has acquired a token. When the gateway unit acquires the communication data and the mode management data, the data relay unit and the mode management unit relay the data so that the communication data and the mode management data are transmitted to the necessary network as shown in FIG. .

  Here, the transition of the operation mode of each control unit using the mode management data in one network will be described with reference to FIG. 3 taking the control units A to D connected to the first network as an example. FIG. 3 shows changes in operation codes transmitted and received by each control unit in the first network when the control unit A can shift from the normal operation mode to the low power consumption operation mode.

  When the operation mode of the control unit A is the normal operation mode, the indicator code Inda in the operation code is 0. Therefore, since it is necessary to instruct each control unit to prohibit the transition to the low power consumption operation mode, the acknowledge code Ack is also zero. On the other hand, since the control units B, C, and D are in a state in which the transition to the low power consumption operation mode is possible, the indicator codes Indb, Indc, and Indd = 1 are output respectively. Since the indicator code Ind = 0 is transmitted from, the acknowledge code Ack outputs 0 indicating that the transition to the low power consumption operation mode is prohibited.

  Thereafter, when the control unit A completes a predetermined control process and can shift from the normal operation mode to the low power consumption operation mode, the indicator code Inda = 1 is output. As a result, the indicator codes Inda to Indd transmitted from the control units A to C all become 1, so that the control unit B enters the low power consumption operation mode with respect to all the control units A to D in the mode management data. The acknowledge code Ack = 1 is output in order to instruct permission to shift. Thereby, each control unit AD shifts from the normal operation mode to the low power consumption operation mode.

  Note that the gateway units X to Z also have a normal operation mode and a low power consumption operation mode. When the operation mode of all control units in the network becomes the low power consumption operation mode, the gateway unit also has a low power consumption mode. Transition to operation mode. When all the control units in the network are in the low power consumption operation mode, data to be relayed quickly is not generated. For this reason, it is preferable that the gateway units X to Z also shift to the low power consumption operation mode to reduce power consumption.

  However, the gateway units X to Z can also have a function as a control unit that controls a predetermined control target device in the vehicle. In such a case, as a matter of course, as a control unit, the operation mode is shifted to the low power consumption operation mode on condition that the operation mode can be shifted to the low power consumption operation mode.

Next, mode management processing in the gateway units X and Z and the centralized management gateway unit Y will be described. First, the mode management processing of the gateway units X and Z will be described based on the flowchart of FIG. 4. First, in step S10, it is determined whether or not data transmitted from another control unit or gateway unit has been received. If it is determined “No” in the determination process of step S10, the process proceeds to step S70. On the other hand, if “Yes” is determined in the determination process of step S10, the process proceeds to step S20.

  In step S20, it is determined based on the received data ID whether the received data is mode management data. If it is determined as “No” in the determination process of step S20, that is, if the communication data shown in FIG. 2A is received, the process proceeds to step S70. On the other hand, if it is determined “Yes” in the determination process of step S20, the process proceeds to step S30.

  In step S30, it is determined whether or not the transmission source control unit or the like is operating in the normal operation mode based on the content of the indicator code Ind of the received mode management data. If “Yes” is determined in the determination process of step S30, the process proceeds to step S40, and mode management that is information for managing the history of operation modes of each control unit and the like provided for each connected network. Set the normal operation mode in the history information. That is, although a plurality of networks are connected to the gateway unit, a plurality of mode management history information is set corresponding to each of the networks, and each mode management history information includes each control in the corresponding network. A mode corresponding to the operation mode of the unit or the like is set.

  On the other hand, if “No” is determined in the determination process of step S30, the process proceeds to step S50. In step S50, referring to the mode management history information corresponding to the network including the unit that has transmitted the mode management data, it is determined whether there is a control unit that has transmitted the mode management data indicating the normal operation mode so far. To do. That is, when mode management data indicating the normal operation mode has already been transmitted from any control unit or the like, the normal operation mode is set in the mode management history information. Therefore, by referring to the mode management history information, it can be determined whether there is a control unit or the like that has transmitted mode management data indicating the normal operation mode.

  If it is determined “Yes” in the determination process in step S50, the process proceeds to step S40 described above. This is because when the operation mode of any one of the control units is the normal operation mode, the operation modes of the other control units need to be set to the normal operation mode. On the other hand, if it is determined as “No” in the determination process of step S50, the condition for allowing the operation mode of each control unit to shift to the low power consumption operation mode is established. Therefore, in step S60, the mode management history information is displayed. Set the low power consumption operation mode.

  In step S70, the gateway units X and Z determine whether it is time to transmit mode management data based on the mode management history information. That is, since the gateway units X and Z transmit mode management data (data relay) at the timing when the transmission right comes to themselves, whether or not the transmission right is acquired in any of the networks to which the gateway units X and Z are connected. Judgment is made. If it is determined as “No” in step S70, the process is temporarily ended. If it is determined as “Yes”, the process proceeds to step S80.

  In step S80, the own operation mode is reflected in the mode management history information. Specifically, even if the mode management history information is set to the low power consumption operation mode, the normal operation mode is set in the mode management history information when the mode management history information needs to operate in the normal operation mode.

  In step S90, the mode management data is created and transmitted to the network determined as the transmission timing of the mode management data based on the mode management history information corresponding to the network other than the network. As described above, the gateway unit has mode management history information indicating the operation mode of the control unit or the like connected to each network for each network. The mode management data is created based on the mode management history information. The created mode management data is transmitted to a network other than the network associated with the mode management history information that is the basis of the data creation. It is.

  The mode management data transmission process in step S90 will be described with reference to FIG. FIG. 5 shows that the gateway (GW) unit X receives the mode management data indicating the normal operation mode from the control unit connected to the second network, relays it to the first network, and further the first network. The mode management data which shows the low power consumption operation mode from the control unit connected to is shown.

  When the conventional GW unit receives the mode management data indicating the normal operation mode from any of the connected networks, each control unit controls each of the connected networks including the network that has received the mode management data. Transmits mode management data for setting the unit to the normal operation mode. In the situation shown in FIG. 5, it is assumed that the GW unit X has transmitted mode management data for setting each control unit to the normal operation mode to all connected networks in the same manner as the conventional GW unit. .

  Then, the central management GW unit Y connected to the second network, based on the mode management data transmitted from the GW unit X, also sets mode management data for setting the normal operation mode for all the connected networks. Send. As a result, a situation occurs in which mode management data for switching each control unit to the normal operation mode is exchanged between the GW unit X and the centralized management GW unit Y, and each control unit enters the low power consumption operation mode. You will not be able to migrate.

  Therefore, in the present embodiment, the GW units X and Z are configured to transmit the mode management data only to networks other than the network associated with the mode management history information that is the basis of the creation. As a result, it is possible to avoid a situation where mode management data for switching to the normal operation mode is exchanged between the GW unit X and the centralized management GW unit Y.

  In step S100, the mode management history information is cleared (low power consumption operation mode) in order to prepare for the next mode management data transmission process, and the process ends.

  However, if all the GW units X to Z are configured to transmit the mode management data only to a network other than the network associated with the mode management history information that is the basis of the creation, as described above, the low The transition timing to the power consumption operation mode depends on the permission timing by any control unit that finally permits the transition from the normal operation mode to the low power consumption operation mode. That is, it becomes impossible for the entire system to manage the transition timing to the low power consumption operation mode.

  For this reason, in this embodiment, the centralized management GW unit Y is provided, and this centralized management GW unit Y can manage the transition timing to the low power consumption operation mode of the entire system. Hereinafter, the mode management process by the centralized management GW unit Y will be described in detail.

  FIG. 6 is a flowchart showing the mode management process executed by the centralized management GW unit Y. The centralized management GW unit Y also basically receives the mode management data from the control unit and the GW units X and Z connected to the network in the same manner as the GW units X and Z. It is determined whether the unit is in the normal operation mode or can be shifted to the low power consumption operation mode (steps S110 to S130). When the mode management data indicating the normal operation mode is received, the mode indicating that the normal operation mode is set in the mode management history information and the transition to the low power consumption operation mode is possible in step S140. If the management data has been received, it is determined in step S150 whether or not the normal operation mode has already been set in the mode management history information.

  However, unlike the above-described GW units X and Z, the centralized management GW unit Y generates mode management data to be transmitted based on the mode management data received from any of the network units. Sends mode management data to all connected networks. For this reason, mode management history information is not set for each network, but the operation mode history of units connected to all networks is collectively managed by a single mode management history information. To do.

  Further, in the centralized management GW unit Y, even if all the units connected to the network can shift to the low power consumption operation mode, mode management instructing the transition to the low power consumption operation mode at that time Mode management in which each unit is instructed to operate in the normal operation mode until a predetermined time elapses from when the transition to the low power consumption operation mode becomes possible instead of transmitting data Send data.

  For example, even when a certain control unit finishes control of the corresponding control target device and determines that the transition to the low power consumption operation mode is possible, it may be necessary to resume control immediately after that. is there. In such a case, if the entire communication system has already shifted to the low power consumption operation mode, a measure for returning each control unit to the normal operation mode is required. It is thought that it is not possible to obtain. Therefore, as described above, the centralized management GW unit Y determines whether or not a predetermined time has elapsed by the process of step S180 from the time when all the units can shift to the low power consumption operation mode. Until the predetermined time elapses, the normal operation mode is set in the mode management history information in step S140 in order to instruct each unit to operate in the normal operation mode. On the other hand, when the predetermined time has elapsed, the process proceeds to step S190 to set the low power consumption operation mode in the mode management history information.

  It should be noted that the time when all the units can be shifted to the low power consumption operation mode is executed when it is determined in step S160 that the low power consumption operation mode is set in the mode management history information. In step S170, the transition timing to the low power consumption operation mode is stored. When this transition timing is stored, the determination in step S150 is “Yes”, so the elapsed time from the transition timing is determined in step S180.

  In step S200, the centralized management GW unit Y determines whether it is time to transmit the mode management data. If it is determined that it is time to transmit, after reflecting its own operation mode to the mode management history information in step S210, the mode management history information is added to all connected networks in step S220. The mode management data created based on this is transmitted. In step S230, the mode management history information is cleared (low power consumption operation mode) in order to prepare for the next mode management data transmission process, and the process ends.

  Thereby, the centralized management GW unit Y reduces the entire communication system from the normal operation mode when a predetermined time elapses from the time when all the units can shift to the low power consumption operation mode. It is possible to shift to the power consumption operation mode. Therefore, when it is necessary to resume control immediately, it is possible to prevent the entire communication system from being transferred to a low power consumption operation mode, so that it is possible to respond quickly when it is necessary to resume control. It becomes.

(Other embodiments)
In the vehicle communication system according to the first embodiment described above, when the centralized management GW unit Y has passed a predetermined time from when all the units can be shifted to the low power consumption operation mode, the communication system The entire system is collectively shifted from the normal operation mode to the low power consumption operation mode.

  However, in addition to the elapsed time since the time when all the units were able to shift to the low power consumption operation mode, for example, the vehicle status such as the occupant's boarding status is shifted to the low power consumption operation mode. It is good as a condition.

  For example, even when the ignition switch is turned off and the engine of the vehicle is stopped, there is a possibility that various control target devices mounted on the vehicle need to be operated in a state where an occupant is on the vehicle. There is. On the contrary, in the state where all the occupants get out of the vehicle and the vehicle is parked, it is not necessary to frequently operate various devices to be controlled. Therefore, when it is detected as a vehicle state that an occupant is in the vehicle, the transition to the low power consumption operation mode is prohibited, and when all the occupants get out of the vehicle, all control units are set to low power. By shifting to the consumption operation mode, it is possible to shift to the low power consumption operation mode at an appropriate timing.

  As a vehicle situation used as a condition for determining the transition to the low power consumption mode, in addition to directly detecting that the occupant is in the vehicle by using a seating sensor or the like, for example, the locked state of each door or the door The presence / absence of opening / closing may be detected.

  FIG. 7 is a flowchart showing the mode management process of the centralized management GW unit Y in the modified embodiment described above. As shown in FIG. 7, in step S185, it is determined whether or not a condition for permitting the transition to the low power consumption mode is satisfied based on the vehicle situation. Other processes are the same as those in the flowchart of FIG.

  Even in this manner, the centralized management unit Y can shift the entire communication system from the normal operation mode to the low power consumption operation mode at a suitable timing.

  Also, once the entire communication system has shifted to the low power consumption operation mode, if the wake-up conditions of some control units are satisfied, the centralized management GW unit Y may not shift the entire system to the normal operation mode. Instead, only a specific network to which some of the control units belong may be operated in the normal operation mode.

  When the vehicle engine is stopped, the in-vehicle battery is not charged. Therefore, it is preferable to suppress the power consumption of the in-vehicle battery as much as possible. For this reason, when some of the control units operate in the normal operation mode when the vehicle engine is stopped, a specific network is formed by collecting control units that must always perform data communication with the control units. However, when the normal operation mode data is received from some of the control units, the normal operation mode data may be transmitted only to the specific network. As a result, the operation mode of the control unit connected to another network is maintained in the low power consumption operation mode, so that it is possible to suppress power consumption.

  A flowchart for the central management GW unit Y to perform such mode management control is shown in FIG. In steps S310 to S330 in FIG. 8, whether or not the mode management data has been received and whether the mode management data is the normal operation mode or the low power consumption operation mode, as in steps S10 to S30 shown in FIG. Is determined.

  In step S340 executed when the mode management data indicates the normal operation mode, the data transmission source control unit determines whether or not it belongs to a specific network. In this determination process, when it is determined that it belongs to a specific network, in step S350, mode management data instructing to operate in the normal operation mode is set only for the specific network. On the other hand, when it is determined that the data transmission source control unit does not belong to a specific network, in step S360, mode management data for instructing all networks to operate in the normal operation mode is set. To do.

  If it is determined in step S370 that it is the transmission timing of the mode management data, the mode management data is transmitted in step S380.

  By such processing, only the control units belonging to a specific network can be operated in the normal operation mode, and the operation modes of the control units belonging to other networks can be maintained in the low power consumption operation mode. Power consumption can be suppressed while performing processing and the like.

  In the first embodiment described above, the GW units X and Z are configured to transmit the mode management data only to a network other than the network associated with the mode management history information that is the basis of the creation. However, the GW units X and Z may perform mode management processing as described below. That is, when the mode management data is received, is the control unit that transmitted the mode management data? It is determined whether it is another GW unit. When the data transmission source is a control unit, the mode management data generated based on the received mode management data is transmitted to all networks including the network to which the data transmission source control unit is connected. To do. On the other hand, when the data transmission source is another GW unit, the mode management data of the transmission source gateway unit is not reflected in the mode management data transmitted to the network to which the data transmission source GW unit is connected.

  Even in this way, it is possible to avoid the situation where the mode management data indicating the normal operation mode is exchanged between the two GW units.

1 is a block diagram illustrating an overall configuration of a vehicle communication system according to a first embodiment. (A) is explanatory drawing which shows an example of the communication data structure used when transmitting / receiving data between control units in order to perform distributed control and cooperative control between control units, (b) is an illustration of a control unit. It is explanatory drawing which shows an example of the mode management data structure for managing an operation mode. It is explanatory drawing which shows the change of the operation code transmitted / received by each control unit in a 1st network when control unit A can transfer to a low power consumption operation mode from a normal operation mode. It is a flowchart which shows the mode management process in GW unit X, Z of 1st Embodiment. It is explanatory drawing for demonstrating the mode management process of GW unit X, Z of 1st Embodiment. It is a flowchart which shows the mode management process of the centralized management unit Y of 1st Embodiment. It is a flowchart which shows the mode management process of the centralized management unit Y of deformation | transformation embodiment. It is a flowchart which shows the mode management process of the centralized management unit Y of other deformation | transformation embodiment.

Claims (8)

A plurality of control units mounted on the vehicle are divided into at least three or more groups, and the control units are connected to each other via a communication line for data communication to form a plurality of networks. A communication system for a vehicle which enables transmission and reception of data between control units connected to the plurality of networks by providing a plurality of gateway units that connect the plurality of networks and relay data. ,
The control unit has, as operation modes, a high power consumption operation mode and a low power consumption operation mode, and other unit in the network to which operation mode data related to the operation mode is connected via the communication line. And when the high power consumption operation mode data is received from another unit, its own operation mode is set to the high power consumption operation mode.
One gateway unit of the plurality of gateway units is a centralized management gateway unit, and a predetermined condition is satisfied even if data indicating that it can shift to the low power consumption operation mode is received from all connected units. Until, a plurality of networks connected to itself, high power consumption operation mode data is transmitted, and when the predetermined condition is satisfied, low power consumption operation mode data is transmitted,
When the other gateway units of the plurality of gateway units receive the operation mode data from a unit connected to one network among the plurality of networks to which the plurality of gateway units are connected, they are transferred to other networks other than the one network. A vehicle communication system, wherein operation mode data is transmitted to a connected unit.   The centralized management gateway unit determines that the predetermined condition is satisfied when an elapsed time after receiving low-power consumption operation mode data from all connected units reaches a predetermined time. The vehicle communication system according to claim 1.   The centralized management gateway unit is based on a detection signal from a detection means for detecting the state of the vehicle, when the state of the vehicle is regarded as a state where all the control units should be shifted to the low power consumption operation mode. The vehicle communication system according to claim 1, wherein it is determined that the predetermined condition is satisfied.   When the vehicle engine is stopped and the high-power consumption operation mode data is received from a predetermined control unit, the centralized management gateway unit is connected to a specific network associated with the control unit. The vehicular communication system according to claim 1, wherein high power consumption operation mode data is transmitted, and low power consumption operation mode data is transmitted to another network.   The control unit operates in the low power consumption operation mode when the ignition switch of the vehicle is turned off, and operates in the high power consumption operation mode when a predetermined activation condition is satisfied. The vehicle communication system according to any one of claims 1 to 4.   The other gateway unit also has a high power consumption operation mode and a low power consumption operation mode as operation modes, and when all the control units in the network to which the gateway unit is connected enter the low power consumption operation mode. 6. The vehicular communication system according to claim 1, wherein the other gateway unit is in a low power consumption operation mode.   If the other gateway unit also has a function as a control unit that controls a predetermined control target device in the vehicle, the operation mode of the control unit can be set to a low power consumption operation mode. The vehicle communication system according to claim 6, wherein the gateway unit has a low power consumption operation mode.   If the unit that transmitted the operation mode data is a control unit, the other gateway unit also transmits data regarding the operation mode to a network including the control unit. If the unit is a gateway unit, the network including the gateway unit is transmitted. The vehicle communication system according to claim 1, wherein the operation mode data is not transmitted to the vehicle.

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