JP2007208739A - Data recording system and data recording method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a data recording system capable of efficiently recording multiple kinds of data held in nodes in a storage means, and to provide a data recording method. <P>SOLUTION: The data recording system includes: a recording device 14 for sorting the multiple kinds of data held in ECUs by each frame ID imparted to the data and recording the data, the ECU-C with a high priority degree, and the ECU-A with a low priority degree. When it is detected that a data frame is not transmitted by the ECU-A by monitoring the frame ID of the data frame flowing in a multiplex communication line 12, the ECU-C adds the frame ID to be added by the ECU-C to the data held by itself and transmits the data. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a data recording system and a data recording method for recording a plurality of different transmission data.

2. Description of the Related Art Conventionally, a system that records data output from a plurality of control devices connected via an in-vehicle LAN in a recording device is known (see, for example, Patent Document 1). In this system, when the vehicle starts to travel, recording is performed on the in-vehicle LAN from a plurality of control devices such as an engine control device, an ABS control device, and a door control device at a predetermined timing (for example, periodically) thereafter. Data addressed to the device is output, and the recording device records the data.
JP 2002-330149 A

  However, in the above-mentioned patent document, no reference is made to what rules are used to record a plurality of types of data sent from a plurality of control devices that are nodes connected by a LAN. Therefore, even if a non-recording storage area occurs in the storage area of the recording apparatus, the non-recording storage area cannot be effectively used.

  Therefore, an object of the present invention is to provide a data recording system and a data recording method capable of efficiently recording various types of data possessed by a node in a storage means.

In order to solve the above problems, as a first invention,
A storage means for storing various types of data of the node;
The node is a data recording system that transmits data to which an ID for classifying data is added, sorts the data for each ID, and records the data in the storage unit,
The nodes include a first node having a higher priority and a second node having a lower priority than the first node,
When the first node detects that the data to which the ID to be added by the second node is not transmitted, the second node adds data that can be transmitted by the first node. Provided is a data recording system characterized by adding data to be added and transmitting data.

A second invention is a data recording system according to the first invention,
A stopping means for stopping data transmission of the second node;
When the first node detects that the data transmission of the second node has been stopped by the stopping unit, the ID that the second node should add to the data that can be transmitted by the first node Provided is a data recording system for transmitting data by adding

According to a third invention, there is provided a data recording system according to the first invention,
Provided is a data recording system in which the first node detects that data to which an ID to be added by the second node is not transmitted is only at startup.

A fourth invention is a data recording method in which a node transmits data to which an ID for classifying data types is added, and the data is sorted by ID and recorded in a storage means,
The nodes include a first node having a higher priority and a second node having a lower priority than the first node,
When the first node detects that the data to which the ID to be added by the second node is not transmitted, the second node adds data that can be transmitted by the first node. Provided is a data recording method characterized by adding data to be added and transmitting data.

A fifth aspect of the invention is a data recording method according to the fourth aspect of the invention,
When the first node detects that the data transmission of the second node has been stopped, the first node adds an ID to be added by the second node to data that can be transmitted by the first node. A data recording method for transmitting data is provided.

According to a sixth invention, there is provided a data recording method according to the fourth invention,
A data recording method is provided in which the first node detects that data to which an ID to be added by the second node is not transmitted is only at startup.

  According to the present invention, various types of data possessed by a node can be efficiently recorded in the storage means.

  The best mode for carrying out the present invention will be described below. FIG. 1 is a configuration diagram of a system according to an embodiment of the present invention. The system according to the present embodiment includes a plurality of nodes 10 such as ECUs and intelligent sensors, which are electronic control units mainly composed of computers provided in various control devices of an automobile, and multiplex communication in which the plurality of nodes 10 are connected. And a recording device 14 connected to the multiplex communication line 12. This system is used, for example, to collect data held by each node 10 in the recording device 14 when performing vehicle failure diagnosis.

  The multiplex communication line 12 is a shared bus composed of a single line or a twisted pair line such as a CAN (Controller Area Network), and transmits data transmitted from each node 10 by time division multiplexing (multiplex communication) according to a predetermined communication protocol. Making it possible. Data transmitted from each node 10 is transmitted to another node 10 or the recording device 14 via the multiplex communication line 12.

  The node 10 includes, for example, a steering angle sensor that outputs a signal corresponding to the steering angle, a yaw rate sensor that outputs a signal corresponding to the yaw rate generated around the center of gravity of the vehicle, a throttle opening, an accelerator opening, an engine water temperature, and the like. Engine ECU that performs engine control based on the vehicle, VSC (Vehicle Stability Control) that stabilizes the turning behavior of the vehicle based on wheel speed, yaw rate, steering rudder angle, etc.-ECU, shift position of the vehicle based on shift operation position, etc. Transmission ECU to control, brake ECU to control the braking force of the vehicle based on the brake pedal force, steering rudder angle, etc., power steering ECU to control the steering assist force based on the steering rudder angle, etc., air conditioner operation switch, interior temperature etc. Based on the air conditioning in the car Doo is air conditioning ECU.

  Each of the nodes 10 includes a microcomputer (microcomputer) incorporating a controller and a communication module connected to the microcomputer. The microcomputer controls the controller according to the communication protocol of the multiplex communication line 12 to be connected, digitizes the output data to be output from its own node 10 to be transmitted to another node 10 via the multiplex communication line 12, and other The input data received from the node 10 via the multiplex communication line 12 is decoded and the control is executed by itself. The communication module is controlled by the controller, and transmits data of the own node 10 to the other node 10 and receives data transmitted from the other node 10 to the own node 10. Each node 10 performs control in its own node based on the state of a sensor or switch connected to its own node 10 or based on data transmitted from another node 10.

  A specific node 10 among all the nodes 10 periodically transmits and receives necessary data to and from another specific node 10 (for example, every 50 ms). For example, the wheel speed information detected by the brake ECU is shared among the VSC-ECU, the brake ECU, and the engine ECU, or the driving torque for stabilizing the turning behavior determined by the VSC-ECU. And control command values for braking force are shared. Further, between the engine ECU and the automatic air conditioner ECU, information on the engine water temperature detected by the engine ECU is shared. These control data are transmitted from the detected node 10 to the node 10 sharing the data, and used for control in the destination node.

  The recording device 14 also has a microcomputer with a built-in controller and a communication module connected to the microcomputer. The recording device 14 controls the controller according to the communication protocol of the multiplex communication line 12, receives data transmitted from each node 10 to the multiplex communication line 12 by the communication module, and records the data. Specifically, the recording device 14 has a stationary recording medium 14b such as a hard disk for storing transmitted data. Each node 10 transmits, for example, data to be recorded in the recording device 14 necessary for diagnosing a vehicle failure to the recording device 14 via the multiplex communication line 12.

  The data that each node 10 transmits to the multiplex communication line 12 is composed of data frames having a predetermined configuration in advance. This data frame includes, for example, a start of frame (SOF) indicating the start of the frame and a frame ID (data transmission priority) that is identification information for distinguishing from the type of transmission data (data frame), that is, other transmission data. An ID field for storing data), a control field for storing data length, etc., a data field for storing the contents of the transmission data itself (for example, wheel speed information, drive torque control command value, etc.), and transmission It consists of a CRC field for checking errors, an ACK field for confirming that reception has been completed normally, and an end of frame (EOF) indicating the end of data.

  The network system according to the present embodiment is a system that allows each node 10 to transmit data to be transmitted to another node 10 via the multiplex communication line 12 by time division multiplexing. That is, each node 10 can start data transmission in a state where no other data is flowing through the multiplex communication line 12, while transmission priority is given when data transmission is simultaneously started from one or more other nodes 10. Data transmission is performed in accordance with the rank, and when data transmission from another node 10 is performed, the data transmission is performed after waiting for a predetermined time. In other words, the node 10 that transmits a frame ID having a high transmission priority is a node having a high priority, and the node 10 that transmits a frame ID having a low transmission priority is a node having a low priority.

  FIG. 2 is a diagram showing the relationship between the data of each node 10 in the system of the present embodiment and the unique frame ID assigned to each data type. Hereinafter, the case where the system of this embodiment has three nodes 10 connected to the multiplex communication line 12 will be described as appropriate, and these nodes 10 are referred to as ECU-A, ECU-B, and ECU-C, respectively. .

  For example, as shown in FIGS. 1 and 2, in this embodiment, the ECU-A has only one type of data (for example, vehicle speed) to be recorded in the recording device 14, and the frame ID = “ 100 "is assigned. Further, the ECU-B has only two types of data to be recorded in the recording device 14 (for example, engine speed and throttle opening). These data include frame ID = “101” and “102”, respectively. "And is assigned. Further, the ECU-C has only one type (for example, yaw rate) of data to be recorded in the recording device 14, and a frame ID = “103” is assigned to the data. Each of the ECU-A, ECU-B, and ECU-C has a frame assigned to the type of the data to be recorded in the recording device 14 at predetermined regular or irregular intervals. The data frame of ID is set, and the data frame is transmitted to the multiplex communication line 12.

  Hereinafter, a method for recording data to be recorded in the recording device 14 sent from the node 10 to the multiplex communication line 12 in the recording device 14 in the system of this embodiment will be described. FIG. 3 is a diagram for explaining a method of storing data transmitted from the plurality of nodes 10 in the recording device 14 in the system of this embodiment.

  In FIG. 3A, when the ECU-A reaches the timing at which the data “A1” to be recorded in the recording device 14 is to be sent to the multiplex communication line 12, the frame ID assigned in advance to the type of the data Is set in a data frame having “100” as “”, and the data frame is transmitted to the multiplex communication line 12. Similarly, the data “A2” and “A3” are transmitted at the timing to be transmitted to the multiplex communication line 12. Further, as shown in FIG. 3 (a), similarly for ECU-B and ECU-C, when it is time to send the data to be recorded in the recording device 14 to the multiplex communication line 12, the data of the data is recorded. The data is set in a data frame having a frame ID assigned in advance to the type, and then the data frame is transmitted to the multiplex communication line 12.

  When the data frame related to the multiplex communication line 12 is transmitted, the recording device 14 reads the frame ID included in the data frame and determines that the data addressed to the recording device 14 is included based on the frame ID. Receive the data. Then, the recording device 14 periodically receives the received frame ID data (for example, 1 second) on the regular recording medium 14b for sorting and storing the data of all the frame IDs to be recorded in advance for each frame ID. Record).

  All the data of the received frame ID may be recorded on the regular recording medium 14b. However, in order not to be redundant, the data is overwritten and updated every reception if the same frame ID is used, and at regular timing. The recording on the steady recording medium 14b may be confirmed. Further, data is stored in the steady recording medium 14b so that the recording time or recording order can be known. In the steady recording medium 14b of the recording apparatus 14 shown in FIG. 3, data groups (for example, A1, B1, B11, C1) stored in the same column are recorded at the same time, and the data groups are As you go to the right, the recorded time becomes newer.

  However, as shown in FIG. 3B, when the ECU-A is not connected to the multiplex communication line 12 for reasons such as not being set due to vehicle specifications, the steady recording medium of the recording device 14 Since data is not recorded in the storage area of the frame ID “100” assigned in advance to 14b, a useless storage area (hereinafter referred to as “non-recording area”) in which data recording is not performed occurs. In order not to generate such a non-recording area, it is only necessary to allow other ECUs other than ECU-A to use such a non-recording area.

  Therefore, the ECU with high priority (high priority ECU) determines the transmission status of the data frame by the ECU lower than its own priority by monitoring the frame ID added to the data frame flowing through the multiplex communication line 12. That is, the high priority ECU monitors whether or not a data frame to which a frame ID having a transmission priority lower than that of the own frame ID is flowing is flowing through the multiplex communication line 12. If the high priority ECU detects that there is no data frame transmission by the ECU lower than its priority by this monitoring (if it detects that there is no transmission of a data frame with a frame ID with a low transmission priority), It can be determined that the storage area of the frame ID assigned in advance to the stationary recording medium 14b is a non-recording area. When detecting a data frame, it can be considered that no data frame has been transmitted by detecting that a data frame having a monitored frame ID has not been transmitted for a certain period of time. The predetermined time for detecting this non-transmission may be equal to or longer than the transmission interval when the data frame whose frame length is the longest in design is transmitted.

  The high-priority ECU that has determined that there is a non-recording area as described above increases and transmits data frames in which its own data is set instead of the ECU that is detected not to transmit the data frame. . For example, the high priority ECU increases the number of its own data frames by the number of frame IDs that have not been detected. At this time, the frame ID of the data frame that has been detected as not being transmitted is assigned to the frame ID of the increased data frame. By doing so, the data frame increased by the high priority ECU is recorded in accordance with the frame ID assigned to the data frame on the steady recording medium 14b of the recording device 14 like the other data frames. .

  The above-described data frame monitoring process by the high priority ECU is preferably executed only once when the high priority ECU is activated. Each ECU after activation is in a state where data transmission is possible. When the high priority ECU is continuously monitored even after it is activated, even if the ECU lower than its own priority stops transmission due to a reset or failure, the ECU assigned in advance to the steady recording medium 14b This is because the storage area of (frame ID) is used. In other words, when an ECU lower than its own priority recovers from a reset state or a failure state, both ECUs transmit data frames to which the same frame ID is added, so that the data frames may collide with each other. Also, ECUs with lower priority than confidence may be added or removed as a retrofit option from a certain point in time. Therefore, it is desirable that the monitoring process is performed every time the high priority ECU is activated.

  The above-described monitoring contents of the data frame based on the frame ID by the high priority ECU will be described with reference to FIG. In FIG. 3, it is assumed that the transmission priority is higher as the frame ID number is larger. In FIG. 3B, ECU-B and ECU-C, which have a larger frame ID number than ECU-A, monitor the frame ID to indicate that no data frame is transmitted by ECU-A, that is, frame ID. It is detected that there is no transmission of a data frame to which “100” is added. ECU-C having a higher priority than ECU-B attaches the frame ID “100” to data C11, C12, C13 that it wants to further record in the recording device 14, and starts data transmission. As a result, as shown in FIG. 3C, the data sent from the ECU-C can be stored in the area where the data originally sent from the ECU-A is stored, and the steady-state storage area 14b is stored. Occurrence of a non-recording area can be suppressed.

  The ECU-B, which has a lower priority than the ECU-C, transmits the data frame to which the frame ID “100” is added by the ECU-C because the ECU-C has no data that the recording device 14 wants to record. If it is detected that there is no fixed time, ECU-B itself may add the frame ID “100” to the data to be recorded in the recording device 14 and start data transmission.

  By the way, there is a case where some serious failure or the like occurs and it is desired to increase the kind of data and the storage amount of the high priority ECU. For example, there are cases where it is desired to increase the types of data that have not been stored until then, or to store data that has been stored until then with higher accuracy. In such a case, the ECU with the lower priority voluntarily transmits the data frame due to the request from the high priority ECU or the occurrence of a predetermined event (for example, a warning flag is turned on or a diagnostic flag is set to notify the abnormality). By stopping, the high priority ECU can store the data that the high priority ECU wants to record in a storage area pre-assigned to the low priority ECU.

  As shown in FIG. 4A, when the ECU-A directly detects the occurrence of the predetermined event 16, or when it is informed by the ECU-C that has detected the occurrence of the predetermined event 16. In order to transfer the storage area assigned to the stationary recording medium 14b itself to another ECU, the transmission is voluntarily stopped. As a result, the ECU-B and the ECU-C having a larger frame ID number than the ECU-A monitor the frame ID to indicate that the data frame is not transmitted by the ECU-A, that is, the frame ID “100” is It detects that there is no transmission of the added data frame. ECU-C having a higher priority than ECU-B attaches the frame ID “100” to data C11, C12, C13 that it wants to further record in the recording device 14, and starts data transmission. As a result, as shown in FIG. 4C, the data sent by the ECU-C can be stored in the area where the data originally sent by the ECU-A is stored. Occurrence of a non-recording area can be suppressed.

  The ECU-B, which has a lower priority than the ECU-C, transmits the data frame to which the frame ID “100” is added by the ECU-C because the ECU-C has no data that the recording device 14 wants to record. If it is detected that there is no fixed time, ECU-B itself may add the frame ID “100” to the data to be recorded in the recording device 14 and start data transmission. Further, since the data frame monitoring process by the high priority ECU shown in FIG. 4 is triggered by the occurrence of a predetermined event as described above, it is not always executed only once when the high priority ECU is activated.

  In addition, when the recording device 14 is removed from the multiplex communication device 12, each ECU has predetermined format data so that it can be identified to which ECU the recorded content of the stationary storage medium 14b of the recording device 14 belongs. Is set to transmit a data frame, and the recording device 14 stores the data together with the format data in the stationary storage medium 14b according to the frame ID. That is, the ECU-A stores the data stored in the storage area of the frame ID “100” allocated in advance to the steady recording medium 14b of the recording apparatus 14 shown in FIGS. 3 (c) and 4 (c). This is for identifying whether the data is the transmitted data or the data transmitted by the ECU-C. If the correspondence between the format data and each ECU is determined as a communication protocol, it is possible to determine which ECU data is based on the value of the format data stored in the steady recording medium 14b. .

  For example, each ECU sets the format data to “00” by default and transmits a data frame. When the ECU-C uses a storage area allocated for another ECU such as the ECU-A (detected that there is no transmission of a data frame assigned with a frame ID allocated to another ECU. In this case, the format data is changed to “01” and the data frame is transmitted. When ECU-B uses a storage area allocated for another ECU such as ECU-A, it is detected that there is no transmission of a data frame assigned with a frame ID allocated to another ECU. If so, the format data is changed to “02” and the data frame is transmitted. Thus, if the format data stored in the steady recording medium 14b is “01”, it can be determined that the stored data is data that the ECU-C has, and the format stored in the steady recording medium 14b. If the data is “02”, it can be determined that the stored data is data that the ECU-B has.

  As described above, according to the contents of the present embodiment, the storage area of the stationary storage medium 14b of the recording device 14 can be efficiently used without waste when storing various types of data of the ECU.

  Further, according to the contents of the present embodiment, the ECU does not directly refer to the storage contents of the steady storage medium 14b of the recording device 14, but monitors the frame ID of the data frame flowing through the multiplex communication line 12 to thereby store the steady storage. The occurrence of a non-recording area of the medium 14b can be detected. On the other hand, the recording device 14 simply records data while sorting into the stationary storage medium 14b according to the frame ID. Therefore, when it is desired to increase the type and storage amount of data to be recorded in the stationary storage medium 14b, it is only necessary to change the transmission procedure of the ECU itself to increase the type and storage amount of data to be recorded. Since there is no need to change the ECU and the storage device 14, the versatility of the system can be maintained while maintaining a simple relationship between the ECU and the recording device 14 even if the type of data and the storage amount are increased.

  Further, according to the contents of this embodiment, since the storage area of the stationary storage medium 14b of the recording device 14 is utilized to the maximum, it is not necessary to increase the storage area of the stationary storage medium 14b of the recording apparatus 14. Investment in increasing the storage area can be suppressed.

  In addition, the system of the present embodiment is a system mounted on a vehicle. Due to a difference in vehicle specifications, a vehicle of a certain vehicle type has all nodes 10 that transmit recordable data to the recording device 14, while others The vehicle of this type may have only a part of the nodes 10 that transmit recordable data to the recording device 14. Even in such a case, according to the contents of the present embodiment, when the data of the node 10 of the vehicle is recorded in the recording device 14, the configuration change or setting change of the node 10 or the recording device 14 is made for each vehicle type. It is possible to realize data recording flexibly corresponding to increase / decrease in the number of nodes 10 due to vehicle type change or the like. In addition, since it is possible to flexibly cope with the increase / decrease in the number of nodes 10 and recording devices 14 connected via the multiplex communication line 12, it is possible to construct a data recording system that is excellent in its expandability.

  The preferred embodiments of the present invention have been described in detail above. However, the present invention is not limited to the above-described embodiments, and various modifications and substitutions can be made to the above-described embodiments without departing from the scope of the present invention. Can be added.

  For example, in the above-described embodiment, all the data in the past predetermined period is stored in the steady recording medium 14b of the recording device 14, but the steady recording medium 14b is stored in the situation where new data should be stored. If there is no remaining capacity corresponding to the data capacity, the oldest data may be deleted in order, and new data may be stored.

  Furthermore, the system of the above embodiment is configured such that various electronic control units included in the automobile are connected via the multiplex communication line 14, but the present invention is not limited to this, and is installed other than the automobile. Then, the electronic control device may be connected via a multiple communication line.

It is a block diagram of the system which is one Example of this invention. It is a figure showing the relationship between the data which each node 10 in the system of a present Example has, and specific flame | frame ID allocated for every data kind. The figure for demonstrating the method of storing the data each transmitted from the some node 10 in the recording apparatus 14 in the system of a present Example is shown. The figure for demonstrating the method of storing the data each transmitted from the some node 10 in the recording apparatus 14 in the system of a present Example when one of the nodes 10 stops transmission voluntarily is shown.

Explanation of symbols

10 node 12 multiplex communication line 14 recording device 14b stationary recording medium

Claims (6)

A storage means for storing various types of data of the node;
The node is a data recording system that transmits data to which an ID for classifying data is added, sorts the data for each ID, and records the data in the storage unit,
The nodes include a first node having a higher priority and a second node having a lower priority than the first node,
When the first node detects that the data to which the ID to be added by the second node is not transmitted, the second node adds data that can be transmitted by the first node. A data recording system, wherein an ID to be added is added and data is transmitted. A stopping means for stopping data transmission of the second node;
When the first node detects that the data transmission of the second node has been stopped by the stopping unit, the ID that the second node should add to the data that can be transmitted by the first node The data recording system according to claim 1, wherein the data is transmitted with the added.   2. The data recording system according to claim 1, wherein the timing at which the first node detects that data to which an ID to be added by the second node is not transmitted is only at startup. A data recording method in which a node transmits data with an ID for classifying data types, sorts the data by ID, and records the data in a storage means,
The nodes include a first node having a higher priority and a second node having a lower priority than the first node,
When the first node detects that the data to which the ID to be added by the second node is not transmitted, the second node adds data that can be transmitted by the first node. A data recording method characterized by adding data to be added and transmitting data.   When the first node detects that the data transmission of the second node has been stopped, the first node adds an ID to be added by the second node to data that can be transmitted by the first node. The data recording method according to claim 4, wherein data is transmitted.   The data recording method according to claim 4, wherein the timing at which the first node detects that the data to which the ID to be added by the second node is not transmitted is only at the time of startup.

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