Vehicle-mounted communication system and communication control method in vehicle-mounted communication system

Abstract

Provided is a vehicle-mounted communication system and a communication control method in the vehicle-mounted communication system, which improves flexibility and / or expandability of a communication network and realizes the vehicle-mounted communication system at low cost. The vehicle-mounted communication system includes a plurality of electronic control devices, a plurality of communication transmission paths, a transmission path switch, and a network control device. The network control device includes a control communication section that performs control communication with the transmission path switch and a control communication management section that manages operation of the control communication in the control communication section. The electronic control device includes a data communication section that performs data communication with other electronic control devices and a data communication management section that manages operation of the data communication in the data communication section. The control communication management section and the data communication management section manage operation of the control communication section and the data communication section, respectively, in such a manner that the control communication and the data communication are performed in different time periods in the communication transmission path.

Description

TECHNICAL FIELD

[0001] The present application relates to a vehicle-mounted communication system and a communication control method in a vehicle-mounted communication system. BACKGROUND

[0002] As a technique for improving flexibility and extensibility of a communication network, a SDN (Software Defined Network) technique is known. In a communication network using the SDN technique, generally, control communication for network control and data communication between devices connected to the communication network are physically configured as different lines.

[0003] In addition, a vehicle network system using a SDN (Software Defined Network) technique is disclosed in Patent Literature 1. The vehicle network system is provided with a first control device that performs network control and a second control device that is provided with a transmission path switch. Further, the first control device and the second control device are connected by two signal lines, and a control message required for open flow control in the SDN is divided into the two signal lines and communicated.

[0004] PRIOR ART LITERATURE

[0005] PATENT LITERATURE

[0006] Patent Literature 1: Japanese Patent Application Publication No. 2019-62290 SUMMARY

[0007] PROBLEMS TO BE SOLVED BY THE INVENTION

[0008] However, a structure in which a plurality of communication transmission paths are connected between devices not only increases the number of communication transmission paths but also increases the number of communication devices, which is disadvantageous in terms of cost.

[0009] An object of the present application is to reduce the number of communication transmission paths connected between devices while improving flexibility and / or extensibility of a communication network, and to realize a vehicle-mounted communication system at low cost.

[0010] MEANS FOR SOLVING THE PROBLEMS

[0011] One embodiment of the present application is a vehicle-mounted communication system including: a plurality of electronic control devices mounted on a vehicle; a plurality of communication transmission paths; a transmission path switch that switches connection of the communication transmission paths; and a network control device that manages operation of the transmission path switch, wherein the network control device includes: a control communication section that performs control communication for operation control of the transmission path switch between the network control device and the transmission path switch via the communication transmission paths; and a control communication management section that manages operation of the control communication in the control communication section, the electronic control devices include: a data communication section that performs data communication for data transmission and reception required for operation of the vehicle between the electronic control devices via the communication transmission paths; and a data communication management section that manages operation of the data communication in the data communication section, and the control communication management section and the data communication management section manage operation of the control communication section and the data communication section, respectively, in such a manner that the control communication and the data communication are performed in different time periods in the communication transmission paths.

[0012] According to another embodiment of the present application, the control communication management section and the data communication management section manage operation of the control communication section and the data communication section, respectively, in such a manner that the control communication and the data communication are performed in mutually different time slots within a frame that is a prescribed length of time in the communication transmission paths.

[0013] According to another embodiment of the present application, the data communication includes communication of service data performed by the plurality of electronic control devices for providing a prescribed service related to operation of the vehicle, and the data communication management section manages operation of the data communication section in such a manner that the communication of service data is performed in time slots allocated for each kind of the service.

[0014] According to another embodiment of the present application, the time slots for the communication of service data in the data communication include dedicated time slots dedicated to one kind of the service and common time slots common to a plurality of kinds of the service.

[0015] According to another embodiment of the present application, the time slots for the data communication include general time slots for communication of arbitrary data.

[0016] According to another embodiment of the present application, the network control device includes a time slot management section that instructs the electronic control devices to change the kind of the service using the dedicated time slots or the common time slots or to change the number of time slots included in the dedicated time slots or the common time slots, in accordance with a running state of the vehicle.

[0017] According to another aspect of the present application, the time slot management section instructs the electronic control device to increase the number of time slots included in the common time slot when the vehicle is stopped, compared to when the vehicle is running.

[0018] According to another aspect of the present application, the time slot management section instructs the electronic control device to change the kind of service using the dedicated time slot or the common time slot, or change the number of time slots included in the dedicated time slot or the common time slot, in accordance with the state of the environment around the vehicle.

[0019] Another aspect of the present application is a communication control method, which is a communication control method in a vehicle-mounted communication system having a plurality of electronic control devices mounted on a vehicle, a plurality of communication transmission paths, a transmission path switch that switches connection of the communication transmission paths, and a network control device that manages operation of the transmission path switch, wherein the communication control method in the vehicle-mounted communication system includes a control communication step in which a first computer possessed by the network control device performs control communication for operation control of the transmission path switch between the communication transmission paths and the transmission path switch, a control communication management step in which the first computer manages operation of the control communication in the control communication step, a data communication step in which a second computer possessed by the electronic control device performs data communication between the communication transmission paths and other electronic control devices for data transmission and reception required for operation of the vehicle, and a data communication management step in which the second computer manages operation of the data communication in the data communication step, and in the control communication management step and the data communication management step, operation of the control communication and the data communication is managed separately in a manner such that the control communication and the data communication are performed in different time periods in the communication transmission paths.

[0020] Effects of Invention

[0021] According to the present application, it is possible to reduce the number of communication transmission paths that connect devices while improving flexibility and / or expansibility of a communication network, and realize a vehicle-mounted communication system at low cost. BRIEF DESCRIPTION OF DRAWINGS

[0022] Figure 1 FIG. 1 is a diagram showing the structure of a vehicle-mounted communication system according to an embodiment of the present application.

[0023] Figure 2 FIG. 4 is a diagram showing the structure of a network control device.

[0024] Figure 3 FIG. 5 is a diagram showing the structure of an electronic control device.

[0025] Figure 4 is a diagram showing an example of a time slot structure of a frame for communication.

[0026] Figure 5 is a flowchart showing processing steps in a vehicle-mounted communication system.

[0027] Explanation of Reference Signs

[0028] 1 vehicle, 2 vehicle-mounted communication system, 3 network control device, 4, 4a, 4b, 4c, 4d, 4e, 4f, 4g, 4h, 4i electronic control device, 5, 5a, 5b, 5c, 5d, 5e transmission path switch, 6, 6a, 6b, 6c, 6d, 6e, 6f, 6g, 6h, 6i, 6j, 6k communication transmission path, 10 first processor, 11 first memory, 12 first communicator, 13 control communication section, 14 control communication management section, 15 time slot management section, 16 first communication control program, 20 second processor, 21 second memory, 22 second communicator, 23 data communication section, 24 data communication management section, 30 frame, 41 control time slot, 42 data time slot, 42a dedicated time slot, 42b common time slot, 42c general-purpose time slot. DETAILED DESCRIPTION

[0029] Hereinafter, an embodiment of the present application will be described with reference to the drawings.

[0030] Figure 1 is a diagram showing the structure of a vehicle-mounted communication system 2 mounted on a vehicle 1 according to an embodiment of the present application. The vehicle-mounted communication system 2 is provided with a network control device 3, a plurality of electronic control devices 4a, 4b, 4c, 4d, 4e, 4f, 4g, 4h, 4i that control the operation of the vehicle 1, and transmission path switches 5a, 5b, 5c, 5d, 5e. Hereinafter, the electronic control devices 4a, 4b, 4c, 4d, 4e, 4f, 4g, 4h, 4i will be collectively referred to as electronic control devices 4. In addition, the transmission path switches 5a, 5b, 5c, 5d, 5e will also be collectively referred to as transmission path switches 5.

[0031] The vehicle-mounted communication system 2 also includes a plurality of communication transmission paths 6a, 6b, 6c, 6d, 6e, 6f, 6g, 6h, 6i, 6j, 6k. Hereinafter, the communication transmission paths 6a, 6b, 6c, 6d, 6e, 6f, 6g, 6h, 6i, 6j, 6k will be collectively referred to as communication transmission paths 6.

[0032] The transmission path switch 5 is an open flow switch that follows the SDN technology. The transmission path switch 5 receives an instruction from the network control device 3 through the open flow control that follows the SDN technology by the network control device 3, and switches the connection between the plurality of communication transmission paths 6 connected to the transmission path switch 5. Thus, the in-vehicle communication system 2 maintains the flexibility and expandability of the communication network that follows the SDN technology.

[0033] The network control device 3 manages the operation of the transmission path switch 5, and manages the communication between the network control device 3, the electronic control device 4, and the transmission path switch 5 in the in-vehicle communication system 2.

[0034] Figure 2 is a diagram showing the structure of the network control device 3. The network control device 3 has a first processor 10, a first memory 11, and a first communicator 12. The first memory 11 is constituted by, for example, a volatile and / or non-volatile semiconductor memory. The first communicator 12 is a transceiver used by the network control device 3 to communicate with the electronic control device 4 and the transmission path switch 5 via the communication transmission path 6.

[0035] The first processor 10 is, for example, a computer having a CPU (Central Processing Unit) or the like. The first processor 10 can also have a structure having a ROM (Read Only Memory) in which a program is written, a RAM (Random Access Memory) for temporarily storing data, or the like. Furthermore, the first processor 10 has a control communication section 13, a control communication management section 14, and a time slot management section 15 as functional elements or functional units.

[0036] These functional elements possessed by the first processor 10 are realized, for example, by executing a first communication control program 16 stored in the first memory 11 by the first processor 10 as a computer. The first communication control program 16 can be stored in advance in any storage medium that is readable by a computer. In addition, all or a part of the above-described functional elements possessed by the first processor 10 can alternatively be constituted by hardware including one or more electronic circuit components. Here, the first processor 10 corresponds to the first computer in the present disclosure.

[0037] The control communication section 13 performs control communication with the transmission path switch 5 via the communication transmission path 6 for control of the operation of the transmission path switch 5, that is, control of the switching operation of the communication transmission path 6. As described above, in the present embodiment, the control communication section 13 controls the switching operation of the transmission path switch 5 by following the OpenFlow control of the SDN technology. That is, the above-described control communication performed by the control communication section 13 with the transmission path switch 5 can be an OpenFlow message following the OpenFlow protocol of the SDN technology.

[0038] In addition, the control communication section 13 also performs control communication with the electronic control device 4 in order to transmit information involved in the communication operation in the electronic control device 4 (for example, time slot management information described later).

[0039] The control communication management section 14 manages the operation of the control communication in the control communication section 13. In the present embodiment, in particular, the control communication management section 14 cooperatively manages the operation of the control communication section 13 with the data communication management section 24 of the electronic control device 4 described later so that the control communication and the data communication are performed in different time periods in the communication transmission path 6.

[0040] Specifically, the control communication management section 14 and the data communication management section 24 manage the operation of the control communication section 13 and the data communication section 23 (described later), respectively, so that the control communication and the data communication in the communication transmission path 6 are performed in mutually different time slots within a frame as a prescribed length of time period. Here, the data communication refers to communication of various data including communication of service data performed among the electronic control devices 4 in order to provide various services (or functions) related to the operation of the vehicle 1.

[0041] Figure 4 is a diagram showing an example of the structure of a time slot included in a frame used in the present embodiment. In Figure 4 In the upper part of the drawing, a frame sequence constituted by a plurality of frames 30 is shown, and in the lower part of the drawing, a time slot sequence constituting one frame 30 is shown. In addition, in the Figure 4 In the drawing, time is assumed to flow from left to right. That is, the frame shown on the left side of the drawing and the time slots are each transmitted first in time. In the Figure 4 In the drawing, the upper part of each time slot included in the time slot sequence is assigned a number.

[0042] In the frame 30, from the SOF (Start Of Frame: start of frame) disposed at the beginning in time at the left end of the drawing, to the EOF (End Of Frame: end of frame) disposed at the end in time at the right end of the drawing.

[0043] In the present embodiment, the frame 30 includes a control slot 41 in which control communication is performed, and a data slot 42 in which data communication is performed. In the illustrated example, the control slot 41 is composed of i slots, and the data slot 42 is composed of (j+k+m) slots. In the present embodiment, the data slot 42 is configured after the control slot 41 in time.

[0044] The number of slots included in each of the control slot 41 and the data slot 42 can be set in advance in the control communication management section 14 and the data communication management section 24 of the electronic control device 4. Alternatively, the number of slots included in each of the control slot 41 and the data slot 42 can be decided by the control communication management section 14 in accordance with the running state or the surrounding situation of the vehicle 1, and notified to the electronic control device 4.

[0045] The control communication management section 14 notifies the control communication section 13 of control slot information indicating the number of slots allocated to the control slot 41. In addition, the control communication management section 14 manages the transmission timing of the SOF indicating the start of the frame 30. For example, the control communication management section 14 instructs the control communication section 13 to transmit the SOF to the communication transmission path 6 at a prescribed time interval corresponding to the time length of the frame 30. The control communication section 13 performs control communication with the transmission path switch 5 using the i slots allocated as the control slot 41 after the SOF is transmitted.

[0046] As will be described later, the data communication management section 24 of the electronic control device 4 detects the start of the frame 30 by receiving the SOF from the communication transmission path 6. The data communication management section 24 transmits a transmission start instruction indicating the timing at which the i+1th slot is to be sent out to the data communication section 23 (to be described later) after the SOF is received. The data communication section 23 starts data communication in response to the case where the transmission start instruction is received.

[0047] In the present embodiment, the data slot 42 includes a dedicated slot 42a dedicated to one service, and a common slot 42b common to a plurality of services, as slots for communication of service data. In addition, the data slot 42 includes a general slot 42c for arbitrary data communication. The dedicated slot 42a is composed of j slots, the common slot 42b is composed of k slots, and the general slot 42c is composed of m slots.

[0048] In the present embodiment, the dedicated time slot 42a is arranged earlier in time than the common time slot 42b and the general time slot 42c, and then the common time slot 42b and the general time slot 42c are arranged in this order. The dedicated time slot 42a is used, for example, for communication of service data by a service having the highest priority among services to be processed. The common time slot 42b is used, for example, for communication of services having a priority lower than or equal to a certain level among services to be processed. Thus, the service having the highest priority is not affected by communication by other services, and communication of service data can be performed promptly, achieving an action having instant responsiveness. In addition, the services having a priority lower than or equal to the certain level can share communication time between services, and execution time of the services can be adjusted.

[0049] In addition, in the general time slot 42c, services having various priorities can communicate, for example, as appropriate. Thus, in a case where service data having different priorities in communication is used in each service, for example, service data having a high priority can be communicated through the dedicated time slot 42a or the common time slot 42b, and service data having a low priority can be communicated through the general time slot 42c. Thus, flexibility and expandability of communication of service data for each service are improved in the data time slot 42.

[0050] In addition, the number of dedicated time slots 42a provided in the data time slot 42 is one in the example shown in FIG. 4, but can be plural. By providing plural dedicated time slots 42a, for example, plural services can use each dedicated time slot 42a arranged earlier in time in order of priority from high to low, and thus the plural services can perform an action with instant responsiveness corresponding to the priority. Figure 4

[0051] Referring to Figure 2 , the time slot management unit 15 instructs the electronic control device 4 to change a kind of service using the dedicated time slot 42a or the common time slot 42b or to change the number of time slots included in the dedicated time slot 42a or the common time slot 42b, in accordance with a running state of the vehicle 1. The instruction is performed, for example, by the time slot management unit 15 transmitting time slot management information listing a kind of service to be allocated and the number of time slots to be allocated for each of the dedicated time slot 42a and the common time slot 42b to the electronic control device 4. Transmission of the time slot management information is performed, for example, by the control communication unit 13 transmitting the time slot management information to the electronic control device 4 as a part of control communication (i.e., during the control time slot 41) in accordance with an instruction of the time slot management unit 15.

[0052] ​For example, the time slot management unit 15 can preferentially allocate a service related to a steering operation of the vehicle 1 to the dedicated time slot 42a in a case where it is possible to determine that the vehicle 1 is traveling on an expressway in accordance with the vehicle speed of the vehicle 1. Alternatively, in a case where a service of a steering operation has already been allocated to the dedicated time slot 42a, the time slot management unit 15 can reduce the number of time slots included in the common time slot 42b or the general time slot 42c and increase the number of time slots included in the dedicated time slot 42a when the vehicle 1 is traveling on an expressway. Thereby, for example, it is possible to increase the priority of a service related to a steering operation that is particularly required on an expressway and reduce the communication speed of an entertainment-related service such as a moving image that is not related to a steering operation using the common time slot 42b, and improve the prompt responsiveness of a service related to the above-described steering operation.

[0053] In addition, for example, the time slot management unit 15 can also instruct the electronic control device 4 so that the number of time slots included in the common time slot 42b is increased when the vehicle 1 is stopped compared to when the vehicle 1 is traveling. Thereby, for example, it is possible to increase the communication speed of an entertainment-related service such as a moving image reproduction using the common time slot 42b when the vehicle 1 is parked, and provide a high-quality reproduced moving image.

[0054] In addition, the time slot management unit 15 instructs the electronic control device 4 to change the kind of a service using the dedicated time slot 42a or the common time slot 42b or change the number of time slots included in the dedicated time slot 42a or the common time slot 42b in accordance with the state of the surrounding environment of the vehicle 1. Here, the "state of the surrounding environment of the vehicle 1" can be, for example, the weather, the air temperature, the number of traffic participants such as vehicles and pedestrians existing in the surroundings.

[0055] Thereby, for example, in a scenario where the number of traffic participants is large and it is expected that the processing load of a service associated with a steering operation will increase, it is possible to increase the priority of communication of a service associated with a steering operation or increase the communication speed to thereby improve the prompt responsiveness of these services, the processing amount of information.

[0056] Figure 3 is a diagram that shows the structure of the electronic control device 4. Furthermore, in Figure 3 , only the structural elements related to data communication performed by the electronic control device 4 are shown for easy understanding of the invention, but the electronic control device 4 can include various functional elements or functional units or devices or electronic circuit components for realizing a prescribed service (or function) in accordance with the related art.

[0057] The electronic control device 4 is provided with a second processor 20, a second memory 21, and a second communicator 22. The second memory 21 is constituted by, for example, a volatile and / or nonvolatile semiconductor memory. The second communicator 22 is a transceiver used by the electronic control device 4 to communicate with the network control device 3 and other electronic control devices 4 via the communication transmission path 6.

[0058] The second processor 20 is, for example, a computer provided with a CPU or the like. The second processor 20 can also be structured with a ROM in which a program is written, a RAM for temporarily storing data, or the like. Also, the second processor 20 is provided with a data communication section 23 and a data communication management section 24 as functional elements or functional units.

[0059] These functional elements provided by the second processor 20 are realized, for example, by executing a second communication control program 25 stored in the second memory 21 by the second processor 20 as a computer. The second communication control program 25 can be stored in advance in any storage medium that is readable by a computer. Further, all or a part of the above-described functional elements provided by the second processor 20 can alternatively be constituted by hardware including one or more electronic circuit components. Here, the second processor 20 corresponds to the second computer in the present disclosure.

[0060] The data communication section 23 performs data communication for the transmission and reception of data required for the operation of the vehicle 1 between the other electronic control devices 4 via the communication transmission path 6. As described above, the data communicated in the data communication includes service data that is communicated between the electronic control devices 4 in order to provide various services (or functions) related to the operation of the vehicle 1.

[0061] The data communication management section 24 manages the operation of the data communication section 23. In the present embodiment, in particular, the data communication management section 24 cooperatively manages the operation of the data communication section 23 with the control communication management section 14 of the above-described network control device 3 such that the data communication and the control communication are performed in different time periods in the communication transmission path 6. Specifically, the data communication management section 24 manages the operation of the data communication section 23 in such a manner that the communication of the service data is performed in time slots allocated in accordance with the kind of service.

[0062] More specifically, the data communication management section 24 receives the time slot management information transmitted from the network control device 3, and notifies the data communication section 23 of the time slot in which the service assigned to the device is performed. In addition, the data communication management section 24 detects the start of the frame 30 by receiving the SOF transmitted from the network control device 3. Then, the data communication management section 24 transmits the transmission start instruction indicating the timing at which the (i+1)th time slot is sent, to the data communication section 23 after receiving the SOF. The data communication section 23 performs data communication using the time slot of the service assigned to the device in response to the case where the transmission start instruction is received.

[0063] In the in-vehicle communication system 2 having the above-described structure, since the control communication and the data communication are performed during different time periods, it is not necessary to use a plurality of signal lines for the control communication and the data communication as in the conventional communication system using the SDN technology, and it is possible to configure the communication transmission path 6 with one communication line or one communication channel. Therefore, in the in-vehicle communication system 2, it is possible to use the SDN technology to improve the flexibility and / or the expansibility as a communication network, and to reduce the number of signal lines or communication channels of the communication transmission path 6 connecting between the network control device 3, the electronic control device 4, and the transmission path switch 5, thereby realizing the in-vehicle communication system 2 at a low cost.

[0064] Next, the steps of the operation in the in-vehicle communication system 2 will be described. Figure 5 is a flowchart indicating the processing steps in the in-vehicle communication system 2. The processing of Figure 5 is repeatedly performed.

[0065] When the processing is started, the control communication management section 14 of the network control device 3 transmits information on the number of time slots assigned to the control time slots 41 (control time slot information) to the control communication section 13 in order to manage the operation of the control communication in the control communication section 13 (S100). Next, the control communication management section 14 transmits the transmission instruction of the SOF to the control communication section 13 (S102). The steps S100 and S102 correspond to the control communication management step.

[0066] Next, the control communication section 13 of the network control device 3 performs the control communication for the operation control of the communication path switching between itself and the transmission path switch 5 according to the transmission instruction of the SOF from the control communication management section 14 (S104). The step S104 corresponds to the control communication step.

[0067] Next, in each of the electronic control devices 4, the data communication management section 24 transmits a transmission start instruction to the data communication section when the start timing of the data slot 42 comes after receiving the SOF (S106). Next, each of the data communication sections 23 of the electronic control devices 4 performs data communication of various data including service data related to the service performed by each of the electronic control devices 4 during the data slot 42 (S108), and ends the process. Here, the steps S106 and S108 correspond to a data communication management step and a data communication step, respectively.

[0068] That is, by the steps S100, S102 as the control communication management steps and the step S106 as the data communication management step, the actions of the step S104 as the control communication step and the step S108 as the data communication step are managed so that the control communication and the data communication are performed in different time periods in the communication transmission path 6.

[0069] Furthermore, the present application is not limited to the structures of the above-described embodiments, and can be implemented in various ways without departing from the gist thereof.

[0070] The above-described embodiments support the following structures.

[0071] (A structure 1) A vehicle-mounted communication system having: a plurality of electronic control devices mounted on a vehicle; a plurality of communication transmission paths; a transmission path switch that switches connection of the communication transmission paths; and a network control device that manages the action of the transmission path switch, wherein the network control device has: a control communication section that performs control communication for action control of the transmission path switch between the network control device and the transmission path switch via the communication transmission paths; and a control communication management section that manages the action of the control communication in the control communication section, the electronic control devices have: a data communication section that performs data communication for data transmission and reception required for the action of the vehicle between the electronic control device and other electronic control device via the communication transmission paths; and a data communication management section that manages the action of the data communication in the data communication section, and the control communication management section and the data communication management section manage the actions of the control communication section and the data communication section, respectively, in a manner such that the control communication and the data communication are performed in different time periods in the communication transmission paths.

[0072] According to the vehicle-mounted communication system of the structure 1, for example, the flexibility and / or the expansibility as a communication network can be improved using the SDN technology, and the communication transmission path can be constituted by one communication line or one communication channel, and the vehicle-mounted communication system can be implemented at low cost.

[0073] The in-vehicle communication system according to Structure 1, wherein the control communication management section and the data communication management section manage the operation of the control communication section and the data communication section, respectively, in such a manner that the control communication and the data communication in the communication transmission path are performed in different time slots within a frame during a time period of a prescribed length.

[0074] The in-vehicle communication system according to Structure 2 enables the control communication and the data communication to be performed easily in different time periods.

[0075] The in-vehicle communication system according to Structure 2, wherein the data communication includes communication of service data performed by a plurality of the electronic control devices in order to provide a prescribed service related to the operation of the vehicle, and the data communication management section manages the operation of the data communication section in such a manner that the communication of the service data is performed in a time slot allocated for each kind of the service.

[0076] The in-vehicle communication system according to Structure 3 enables the reliability of communication to be improved by reducing the probability of collision of communication data between services, since the time slot to be used is allocated for each kind of service.

[0077] The in-vehicle communication system according to Structure 3, wherein the time slot for the communication of the service data in the data communication includes a dedicated time slot dedicated to one kind of the service, and a common time slot common to a plurality of the services.

[0078] The in-vehicle communication system according to Structure 4 enables a service having the highest priority to be allocated to the dedicated time slot to provide a service having prompt responsiveness, and other services having a priority of a middle level or lower to be allocated to the common time slot to realize adjustment of the execution time of the services, for example.

[0079] The in-vehicle communication system according to Structure 4, wherein the time slot for the data communication includes a general time slot for communication of arbitrary data.

[0080] The in-vehicle communication system according to Structure 5 enables flexible and expandable data communication for a service by allocating service data having a low priority to the general time slot in place of or in addition to the service, for example.

[0081] The in-vehicle communication system according to Structure 4 or 5, wherein the network control device has a time slot management section that instructs the electronic control devices to change the kind of the service using the dedicated time slot or the common time slot, or to change the number of time slots included in the dedicated time slot or the common time slot, in accordance with the running state of the vehicle.

[0082] According to the in-vehicle communication system according to Structure 6, for example, in a case where it is determined from the vehicle speed of the vehicle 1 that the vehicle 1 is traveling on an expressway, it is possible to increase the priority of services related to a steering operation that is particularly required on an expressway and to reduce the communication speed of services related to entertainment such as dynamic image reproduction that is unrelated to the steering operation, thereby improving the immediacy of response of the above-mentioned services related to the steering operation.

[0083] (Structure 7) The in-vehicle communication system according to Structure 6, wherein the time slot management section instructs the electronic control device to increase the number of time slots included in the common time slot when the vehicle is stopped, as compared to when the vehicle is traveling.

[0084] According to the in-vehicle communication system according to Structure 7, for example, it is possible to increase the communication speed of services related to entertainment such as dynamic image reproduction using the common time slot when the vehicle is stopped, and to provide a reproduction dynamic image with high quality.

[0085] (Structure 8) The in-vehicle communication system according to Structure 6 or 7, wherein the time slot management section instructs the electronic control device to change the kind of services using the dedicated time slot or the common time slot or to change the number of time slots included in the dedicated time slot or the common time slot, in accordance with the state of the environment around the vehicle.

[0086] According to the in-vehicle communication system according to Structure 8, for example, in a scenario where the number of traffic participants is large and it is expected that the processing load of services related to a steering operation is high, it is possible to increase the priority of communication or to increase the communication speed of services related to a steering operation, thereby improving the immediacy of response of these services, the amount of processing of information.

[0087] A communication control method in a vehicle-mounted communication system having a plurality of electronic control devices mounted on a vehicle, a plurality of communication transmission paths, a transmission path switch that switches connection of the communication transmission paths, and a network control device that manages operation of the transmission path switch, wherein the communication control method in the vehicle-mounted communication system includes: a control communication step in which a first computer possessed by the network control device performs control communication for operation control of the transmission path switch via the communication transmission path and the transmission path switch; a control communication management step in which the first computer manages operation of the control communication in the control communication step; a data communication step in which a second computer possessed by the electronic control device performs data communication for data transmission and reception required for operation of the vehicle via the communication transmission path and other electronic control devices; and a data communication management step in which the second computer manages operation of the data communication in the data communication step, and in the control communication management step and the data communication management step, operation of the control communication and the data communication is respectively managed in a manner such that the control communication and the data communication are performed in different time periods in the communication transmission path.

[0088] According to the communication control method of Structure 9, flexibility and / or expansibility as a communication network are improved using, for example, an SDN technique, and the communication transmission path can be constituted by one communication line or one communication channel, and the vehicle-mounted communication system can be implemented at low cost.

Claims

1. A vehicle-mounted communication system comprising: a plurality of electronic control devices mounted in a vehicle; a plurality of communication transmission paths; a transmission path switch for switching connections of the communication transmission paths; and a network control device for managing the operation of the transmission path switch, wherein... The transmission path switches are open flow switches used to implement software-defined networking. Multiple transmission path switches connect multiple communication transmission paths to each other. Each transmission path switch receives instructions from the network control device, which performs open flow control according to software-defined networking technology, and switches the connections between the multiple communication transmission paths connected to each transmission path switch. The network control device has a first processor. The first processor performs control communication for the operation control of each of the transmission path switches between the network control device and each of the transmission path switches via each of the communication transmission paths. The first processor manages the actions of the control communication. Each of the electronic control devices has a second processor. The second processor performs data communication between the electronic control device and other electronic control devices via the respective communication transmission paths, the data communication being used for data transmission and reception required for the operation of the vehicle. The second processor manages the data communication operations. The first processor and the second processor manage the actions of the control communication and the data communication respectively, in a manner that allows the control communication and the data communication to occur at different times during the communication transmission path. The first processor and the second processor manage the operations of the control communication and the data communication in the communication transmission path respectively, in a manner that the control communication and the data communication are executed in different time slots within a frame of a predetermined time period. The data communication includes communication of service data between the multiple electronic control devices to provide prescribed services related to the operation of the vehicle. The second processor manages the actions of the data communication in a manner that the communication of the service data is performed in time slots allocated according to each type of the service. In the data communication, the time slots used for communication of the service data include dedicated time slots for one of the services and shared time slots shared by multiple services. The first processor, based on the vehicle's driving status or the state of the vehicle's surrounding environment, preferentially changes the services allocated to the dedicated time slots, and changes the types of services and the number of time slots that should be allocated to the dedicated time slots and the shared time slots, respectively.

2. The vehicle-mounted communication system according to claim 1, wherein, The time slots used for the data communication include general time slots for communication of any data.

3. The vehicle-mounted communication system according to claim 1, wherein, The first processor instructs the electronic control device to increase the number of time slots included in the shared time slot when the vehicle is stopped, compared to when the vehicle is moving.

4. A communication control method in a vehicle-mounted communication system, the vehicle-mounted communication system comprising: a plurality of electronic control devices mounted on a vehicle; Multiple communication transmission paths; a transmission path switch that switches the connection of the communication transmission paths; and a network control device that manages the operation of the transmission path switch, wherein, The transmission path switches are open flow switches used to implement software-defined networking. Multiple transmission path switches connect multiple communication transmission paths to each other. Each transmission path switch receives instructions from the network control device, which performs open flow control according to software-defined networking technology, and switches the connections between the multiple communication transmission paths connected to each transmission path switch. The communication control method in the vehicle-mounted communication system includes the following steps: In the control communication step, the first computer of the network control device performs control communication for the operation control of each of the transmission path switches via each of the communication transmission paths and each of the transmission path switches; The control communication management step involves the first computer managing the control communication actions within that step. In the data communication step, the second computer of the electronic control device performs data communication with other electronic control devices via each of the communication transmission paths, the data communication being used for data transmission and reception required for the operation of the vehicle; and In the data communication management step, the second computer manages the data communication actions within the data communication step. In the control communication management step and the data communication management step, the actions of the control communication and the data communication are managed respectively in a manner that allows the control communication and the data communication to occur at different times during the communication transmission path. In the control communication management step and the data communication management step, the actions of the control communication and the data communication in the communication transmission path are managed respectively in a manner that the control communication and the data communication are executed in different time slots within a frame of a predetermined length. The data communication includes communication of service data between the multiple electronic control devices to provide prescribed services related to the operation of the vehicle. The second computer manages the actions of the data communication in a manner that enables the communication of the service data to be performed in time slots allocated according to each type of the service. In the data communication, the time slots used for communication of the service data include dedicated time slots for one of the services and shared time slots shared by multiple services. The first computer, based on the vehicle's driving status or the state of the vehicle's surrounding environment, prioritizes changing the services allocated to the dedicated time slots, and changes the types of services and the number of time slots that should be allocated to the dedicated time slots and the shared time slots, respectively.

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