JP2010247791A - Input/output device and control system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an input/output device attaining wire-saving of a system, and capable of making transfer of data in the whole of a control system efficient and fast while reducing a processing load in a control device, and to provide the control system including the input/output device. <P>SOLUTION: When it is preferable that data from sensors 1b, 1f, 1j are simultaneously received by an ECU (Electronic Control Unit) 3b, IOUs (In-Out Units) 5a, 5b, 5d respectively inputting the data from the sensors 1b, 1f, 1j and transmitting that to a CAN (Controller Area Network) bus 7 detect a point of time when the data is transmitted each other, and adjust a transmitting timing so as to shorten time difference between a point of time when the data is transmitted and a point of time when the data transmitted by themselves is transmitted. An IOU 5b transmitting the data from another sensor 1d adjusts transmitting timing so as to extend time difference from the point of time when the data from the sensor 1b, 1f, 1j are transmitted. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an input / output device that relays input / output to / from a control device of a plurality of devices between a plurality of devices and a control device that controls the devices using information from the plurality of devices. In particular, it is possible to reduce the processing load in the control device that receives and uses the data by making the output timing of the data input from each device almost the same as or different from the specific data, and in the system The present invention relates to an input / output device capable of improving the efficiency of data exchange and a control system including the input / output device.

  In recent years, control systems that control a large number of devices and realize various functions as a whole have become widespread. A control device is connected to each device, and each control device is provided with a communication means to exchange data with each other, and each control device does not perform independent control, but can be obtained via other control devices. Control systems that execute control in cooperation, such as controlling a device to be controlled corresponding to itself based on data obtained, are used in various fields.

  In such a control system, as the function increases, the number of devices to be controlled increases, and the number of devices such as sensors that acquire or measure data used for control also increases.

  Particularly in the field of vehicles, a large number of devices such as actuators or sensors corresponding to various functions are arranged in the vehicle, and ECUs (Electronic Control Units) are arranged and operated as control devices for controlling each device. Yes. Vehicle control is shifting from mechanical control to electrical control, and further, specialization of functions realized by the control system, increase in functions that can be realized, and diversification are progressing. As a result, devices such as actuators and sensors mounted on the vehicle are increasing.

  Thus, the number of devices such as devices to be controlled or sensors that acquire data used for control increases. When the number of devices increases, in the configuration in which the control devices correspond to the respective devices, the number of control devices also increases and the communication load in mutual communication may increase. In this case, there arises a problem such as a delay in data transmission / reception or a time difference in reception even though the data is to be received almost simultaneously.

  On the other hand, in a control system using an ECU in a vehicle, a configuration is proposed in which inputs and outputs with devices such as sensors and actuators are aggregated due to the following problems (see Patent Documents 1 and 2). Since the number of ECUs is increasing as described above, and the number of ECUs connected to one communication line is limited due to problems such as ringing prevention, the number of communication lines increases. Furthermore, the number of signal lines increases as the number of devices increases. Particularly in the field of vehicles, the weight reduction of the entire vehicle is an important issue in consideration of the improvement of fuel consumption and the influence on the environment. Since weight reduction of the wire harness including various electric wires such as communication lines, signal lines, and power lines greatly affects the weight reduction, it is desired to reduce the weight and reduce the wires of the various electric wires themselves.

  Therefore, in Patent Document 1, line saving is achieved by adopting a configuration in which the input / output device multiplexes data obtained from each device and transmits the multiplexed data to an in-vehicle ECU that is a control device. Patent Document 2 proposes an input / output device that can be reduced in size by reducing the number of parts of an ECU by using a shift register to transmit data multiplexed by communication. .

JP-A-7-95659 JP 2008-296871 A

  As disclosed in Patent Documents 1 and 2, the operation for data output from a plurality of devices is performed by a common operation means, and further information is multiplexed and transmitted to the ECU via communication, or via a shift register. With this configuration, communication lines and signal lines can be reduced.

  In the configurations disclosed in Patent Documents 1 and 2, data obtained from a sensor or the like can be output collectively. However, the timing at which data is output from the sensor or actuator is arbitrary. In the input / output devices disclosed in Patent Documents 1 and 2, it is not considered to appropriately adjust the timing of outputting data obtained at an arbitrary timing according to a request from the ECU using these data.

  The present invention has been made in view of such circumstances, and an input / output device that processes input / output of data between a plurality of devices constituting the control system and a control device of each device transmits the data to the control device. When transmitting by the communication means, the transmission timing is made almost the same as or different from the specific data, thereby reducing the processing load in the control device and increasing the efficiency of data exchange in the system. It is an object of the present invention to provide an input / output device that can be used and a control system including the input / output device.

  The input / output device according to the first invention is connected to a plurality of devices that input or output data and a control device that uses data output from any of the plurality of devices or controls any of the devices. Specific data is controlled in an input / output device comprising means for periodically transmitting data output from the device to the control device and means for inputting control data from the control device to any device The time difference is shortened or extended based on the time difference between the detection means for detecting the time point transmitted from the device or other input / output device, the time point detected by the means, and the data transmission time point when the data is transmitted by itself. And adjusting means for adjusting the transmission point of the next data.

  The input / output device according to the second invention is a means for storing, for each group, identification information of data previously divided into a plurality of groups and identification information of data set as the specific data, one for each group The adjustment means reduces the time difference between the detected time and the transmission time of the data to be transmitted when the detection means detects the time when the specific data of the same group as the data transmitted by the adjustment means is transmitted. As described above, it is characterized in that the next data transmission time point is adjusted.

  In the input / output device according to a third aspect of the present invention, when the adjustment means detects the transmission time of specific data of a group different from the specific data when the data transmitted by the adjustment means is specific data, It is characterized in that the next data transmission time is adjusted so that the time difference between the detected time and the transmission time of the data to be transmitted is extended.

  The input / output device according to a fourth invention is characterized in that attributes are associated with each data, and the group is divided so that data associated with the same attribute is the same group. To do.

  The input / output device according to a fifth aspect is characterized in that data having a short transmission cycle in each group is set as the specific data.

  The input / output device according to a sixth aspect of the invention is characterized in that each group is divided so as to be composed of data whose transmission cycle is a multiple of the transmission cycle of specific data.

  The input / output device according to a seventh aspect is characterized in that each data is given a priority, and data having a high priority in each group is set as the specific data.

  A control system according to an eighth aspect of the present invention includes a plurality of devices that input or output data, a control device that uses or outputs data output from any of the plurality of devices, and the plurality of devices Connected to the plurality of devices and the plurality of control devices, means for periodically transmitting data output from the devices to the control device, and means for inputting control data from the control device to any of the devices The plurality of control devices and the input / output devices are connected to a communication line in a bus shape, and the plurality of control devices control a plurality of devices via the input / output devices. In the control system, the input / output device includes detection means for detecting a time point when specific data is transmitted from the control device or another input / output device to the communication line, a time point when the means detects, and a previous time. Based on the time difference between the data transmission time of its own by the communication means to transmit data, characterized by comprising an adjustment means for adjusting the next data transmission time so that the time difference is shortened or lengthened.

  In the first invention and the eighth invention, the input / output device that processes input / output with a plurality of devices and the control device that controls the devices is configured to periodically transmit data from the device to the control device by communication. The timing at which the data is transmitted is adjusted on the basis of the time at which specific data transmitted from another input / output device or control device is transmitted. Certain data is subsequently transmitted at a timing that shortens the time difference from each point in the cycle in which the specific data is transmitted, and can be received by the control device or other input / output device almost simultaneously with the specific data. . In addition, since some other data is transmitted later at a timing at which the time difference from each point in the cycle in which the specific data is transmitted is extended, the timing at which the specific data is transmitted is separated from the timing. Received by the control device or other input / output device.

  In the second invention, in the first invention, the data input / output between the plurality of devices and the control device is divided into a plurality of groups in advance, and one data is set as specific data in each group, and the same The transmission time of the data in the group is adjusted so that the time difference from the transmission time of the specific data in the group is shortened. As a result, data of the same group having high relevance can be received almost simultaneously by the control device or another input / output device.

  In the third invention, in the second invention, when specific data is transmitted, the time difference from the transmission time of specific data in another group is adjusted to be extended. As a result, the specific data of each group are separated from each other at the time of data transmission. Since the transmission time of the data of the same group is adjusted to be almost the same as the specific data of the group, the transmission time of the specific data of each group is separated, so that it is not limited to between specific data. The transmission time differs between different groups of data.

  In the fourth invention, data having the same attribute are grouped according to the attribute of the data. The attribute is, for example, a system of a device to be controlled that is controlled based on the data. Thereby, data having the same attribute is received almost simultaneously by the control device or another input / output device, and the timing at which the data having different attributes is received is separated. It is presumed that data having the same attribute is used for control at the same time. However, these data can be received almost simultaneously by the control apparatus, and at that time, it is efficient without being hindered by data of other attributes.

  In the fifth invention, data having a short transmission cycle in each group is set as specific data. As a result, the process of matching the transmission timing with the transmission time of specific data within the same group becomes simple and efficient.

  In the sixth aspect of the invention, the data of each group has a transmission cycle that is a multiple of each other. Therefore, the process of matching the transmission timing with the transmission time of specific data within the same group is simplified. The deviation from the transmission timing with the specific data is constant, and once the timing is matched, the transmission is stably performed at substantially the same timing, so the processing becomes efficient.

  In the seventh invention, data having a high priority in each group is set as the specific data. Since data with high priority is transmitted as specific data and transmission timings are separated from each other, data with high priority does not collide and data exchange is efficient.

  In the case of the present invention, a control system including each device such as an actuator and a sensor and a control device that provides control data to the actuator based on data output from the sensor. Since input / output is concentrated in the input / output device, communication lines, signal lines, and the like can be reduced, and system line-saving can be achieved.

  Further, the data transmission timings are mutually adjusted by the plurality of input / output devices so that the data divided into groups is received by the control device for each group. Therefore, the control device can acquire and process highly relevant data used together for control almost simultaneously, and the data transfer is efficient. That is, data simultaneity is improved and control accuracy in the control device is also improved. In addition, since the transmission / reception timings of the data in different groups are shifted, the communication efficiency on the communication line connecting the control device and the input / output device is improved, and the speed is increased.

  The control device according to the present invention does not require processing such as waiting for control using the data until the data of the same group output at each arbitrary timing can be received, thereby reducing the processing load on the control device. It is also possible.

It is a block diagram which shows the structure of the vehicle-mounted control system in this Embodiment. It is a block diagram which simplifies and shows the connection of each apparatus to the CAN bus of the vehicle-mounted control system of this Embodiment. It is a block diagram which shows the internal structure of IOU in this Embodiment. It is explanatory drawing which shows content examples, such as ID of each data in this Embodiment, a use, and a transmission cycle. It is explanatory drawing which shows the content example of the information of grouping memorize | stored in the memory | storage part of IOU in this Embodiment. It is explanatory drawing which shows the outline | summary of the adjustment process of the transmission timing by IOU in this Embodiment. It is explanatory drawing which shows typically the specific example of the result of the adjustment process of the transmission timing by IOU in this Embodiment.

  Hereinafter, the present invention will be specifically described with reference to the drawings showing embodiments thereof. In the embodiment described below, an example in which the input / output device according to the present invention is used in an in-vehicle control system including a large number of actuators, sensors, and ECUs mounted on a vehicle will be described.

  FIG. 1 is a configuration diagram showing the configuration of the in-vehicle control system in the present embodiment. The in-vehicle control system includes various sensors 1a, 1b, 1c, 1d, 1e, 1f, 1g, 1h such as a temperature sensor or camera mounted on the front of the vehicle, a wheel speed sensor attached to a tire shaft, or a yaw rate sensor. , 1i, 1j, various actuators 2a, 2b,... Such as brakes, headlights, door locks, etc., and ECU 3a for controlling the operation of the actuators 2a, 2b,. , 3b, and a GW (Gate Way) 4 that relays data exchange between different networks, and further, various sensors 1a, 1b,... And actuators 2a, 2b,. IOU (In-Out Unit: input / output unit) 5a, 5b, 5c, 5d for processing the output.

  The various sensors 1a, 1b,... And the actuators 2a, 2b,... Are connected to the IOUs 5a, 5b,. The sensors 1a, 1b,... And the actuators 2a, 2b,... May communicate with the IOUs 5a, 5b, 5c, 5d via LIN (Local Interconnect Network).

  The ECUs 3a, 3b, GW4, and IOUs 5a, 5b, 5c, 5d are each connected to a CAN (Controller Area Network) bus 7, and transmit / receive control data to / from each other. In the present embodiment, the communication protocol between the ECUs 3a, 3b, GW4, and IOUs 5a, 5b, 5c, 5d is CAN, but is not limited to this, and other event-driven communication protocols may be used.

  Are connected to the IOUs 5a, 5b,... And the actuators 2a, 2b,. Which sensor 1a, 1b,... And actuator 2a, 2b,... Is connected to the same IOU 5a (or IOU 5b, 5c, 5d) is designed based on the physical distance. In the example shown in FIG. 1, since the three sensors 1a, 1b, 1c and the one actuator 2a in the left part of the front part of the vehicle are arranged close to each other, they are connected to one IOU 5a. Further, the sensors 1c and 1d arranged in the center of the front portion of the vehicle are also connected to the same IOU 5b. Three sensors 1e, 1f, 1g in the right part of the front part of the vehicle and one actuator 2b are connected to the same IOU 5c, and two sensors 1i, 1j in the rear part of the vehicle and two actuators 2c, 2d are the same. Connected to the IOU 5d. The sensors 1a, 1b,... And the actuators 2a, 2b,... Are not connected to the ECUs 3a, 3b, but are connected to the IOUs 5a, 5b,. By integrating the input / output between the signal lines 6, the length of the signal lines 6, 6,. In particular, the left part and the right part of the front part of the vehicle have a large number of devices such as sensors 1a, 1b,.

  However, data including information such as measurement values detected by the sensors 1a, 1b, and 1c connected to the IOU 5a is not always used for controlling the operation of the actuator 2a connected to the same IOU 5a. As described above, the sensors 1a, 1b, 1c and the actuator 2a are connected to the IOU 5a based on the physical arrangement, and therefore may be functionally separated. For example, in order to control the operation of the actuator 2b installed at the front of the vehicle connected to the IOU 5c by the processing of the ECU 3b, not only the data obtained from the sensor 1b and the sensor 1h installed at the front of the vehicle, In some cases, data such as measured values obtained by the sensor 1j mounted on the rear part of the sensor is also used. In this case, it is desirable that the data from the sensors 1b, 1h, 1j can be simultaneously received by the ECU 3b.

  FIG. 2 is a block diagram showing a simplified connection of each device to the CAN bus 7 of the in-vehicle control system of the present embodiment. Information such as measured values detected by the sensors from the sensors 1a, 1b,... And information indicating the control state from the actuators 2a, 2b,. The IOUs 5a, 5b, and 5c also periodically transmit data from the sensors 1a, 1b,... Or data from the actuators 2a, 2b,. The GW 4 also periodically transmits data such as measured values output from other sensors (not shown) via the other CAN bus 7 to the CAN bus 7. As a result, the ECUs 3a, 3b that control the actuators 2a, 2b,... Can always acquire the latest data.

  Thus, when data is periodically transmitted from each IOU 5a, 5b, 5c, 5d, it is desirable that the data from the sensors 1b, 1h, 1j can be simultaneously received by the ECU 3b as in the above-described example. Similarly, data from the other sensors 1a, 1c,... Is received simultaneously depending on whether the use of data from each sensor 1a, 1c,. There is data to do.

  In this embodiment, the sensors 1a, 1b,... And the actuators 2a, 2b,... Are classified into two systems, that is, a body system (B) and a control system (C). In order to simplify the explanation, attention is paid to only two systems. The ECU 3a controls the operations of the body actuators 2a and 2b, and the ECU 3b controls the operations of the control actuators 2c and 2d. At this time, it is assumed that the sensors 1a, 1d, and 1f are body systems, and the sensors 1b, 1c, 1e, 1g, 1h, 1i, and 1j are control systems. In this case, data from the body sensors 1a, 1d,... Is used by the ECU 3a, and data from the control sensors 1b, 1c,.

  Thus, since each sensor 1a, 1b,... Is connected to each IOU 5a, 5b, 5c, 5d based on the physical arrangement relationship, sensors 1a, 1b,. For example, the sensors 1b, 1h, and 1j that are preferably data sources that can receive data at the same time are connected to different IOUs 5a, 5c, and 5d, respectively, and therefore cannot be collectively transmitted in one CAN frame.

  Therefore, the IOUs 5a, 5b,... In the first embodiment physically collect inputs and outputs between the sensors 1a, 1b,... And the actuators 2a, 2b,. In addition, the timing at which data is output from the IOUs 5a, 5b,... Is adjusted and output so that highly relevant data that are used simultaneously for control are transmitted in close proximity to each other.

  A configuration for realizing such a function will be described in the IOUs 5a, 5b,. FIG. 3 is a block diagram showing an internal configuration of the IOU 5a in the first embodiment. Since the internal configuration of the IOU 5b is the same as the internal configuration of the IOU 5a, description thereof is omitted.

  The IOU 5a is configured using a microcomputer, and includes a control unit 50a, a storage unit 51a, a communication unit 52a, a connection unit 53a, and a timing unit 54a. The IOUs 5a and 5b may be configured by ASIC (Application Specific Integrated Circuit).

  The control unit 50a is configured to control the operation of each component unit by receiving power from a power supply device such as a vehicle battery and an alternator (not shown) using a CPU (Central Processing Unit) or the like.

  The storage unit 51a uses a nonvolatile memory such as a flash memory. The storage unit 51a stores a computer program that realizes a data transmission timing adjustment process, which will be described later, in the control unit 50a, or various types of information that the control unit 50a refers to during processing. In the storage unit 51a, data output from the connected sensors 1a, 1b, 1c, data indicating the operation state of the actuators 2a, 2b to be controlled, ECUs 3a, 3b, GW4, or other IOUs 5b , 5c, 5d may be stored data for controlling the actuators 2a, 2b. Data from these sensors 1a, 1b, 1c, ECUs 3a, 3b, GW4, etc. used random access memories such as SRAM (Static Random Access Memory) and DRAM (Dynamic Random Access Memory) different from the storage unit 51a. It is good also as a structure memorize | stored separately in a memory | storage part.

  The communication unit 52a has functions of a CAN transceiver and a CAN controller for realizing communication via the CAN bus 7. Specifically, communication on the CAN bus 7 is controlled. As will be described later, when data is given from the control unit 50a, the communication unit 52a places the data on a CAN protocol signal (CAN frame), and realizes transmission of a signal in the physical layer by a CAN transceiver. Further, when the communication unit 52a receives a CAN frame such as data transmitted from the ECUs 3a, 3b, GW4, and the other IOUs 5b, 5c, and 5d via the CAN bus 7, the data or the transmission request is received. Extract and notify the control unit 50a. Thereby, the control part 50a can recognize the time when each data is transmitted to the CAN bus 7. FIG.

  The connection unit 53a is an interface of the IOU 5a, and the sensors 1a, 1b, 1c and the actuator 2a are connected via signal lines 6, 6,. In the connection unit 53a, the sensors 1a, 1b, 1c and the actuator 2a notify the control unit 50a of signals from the signal lines 6, 6,..., And the data signals instructed from the control unit 50a are transmitted to the sensors 1a, 1b, 1c. Or it outputs to either of the actuators 2a. It may have D / A conversion and A / D conversion functions.

  The timer 54a measures the passage of time by counting pulses using a clock circuit that outputs a pulse signal at a predetermined frequency. The control unit 50a can acquire time information from the timing unit 54a at an arbitrary timing.

  A process for adjusting the transmission timing when the IOUs 5a, 5b,... Configured as described above transmit data output from the sensors 1a, 1b, 1c to the CAN bus 7 will be described below.

  First, data transmitted by the IOUs 5a, 5b,... Are set at the design stage by the sensors 1a, 1b,. Each of the IOUs 5a, 5b,... Basically stores the identification information (ID) of the data transmitted by itself, the transmission cycle in the storage unit 51a,..., And the transmission cycle is measured by the timing units 54a,. Transmit according to the transmission cycle.

  FIG. 4 is an explanatory diagram showing an example of contents such as ID, usage, and transmission cycle of each data in the present embodiment. “CAN ID” is assigned to the data transmitted and received between the ECUs 3a, 3b, GW4, and IOUs 5a, 5b,... According to the CAN protocol. In communication in the first embodiment, a plurality of data is collected and transmitted. For example, the control sensors 1b and 1c are connected to the IOU 5a. The IOU 5a collectively transmits data from the sensors 1b and 1c of the control system in one CAN frame. In this case, “CAN ID” is assigned according to the combination of data. This is because the ECUs 3a and 3b that receive data can recognize what data is included in the CAN frame. Hereinafter, it is assumed that each “CAN ID” is assigned by a combination of data included in the same CAN frame.

  In FIG. 4, identification information (CAN ID) of data (frame) transmitted from the IOUs 5a, 5b, 5c, and 5d in the present embodiment, the priority of each frame, a system that is the use of data as a data attribute, In addition, the transmission cycle (msec) of each data is shown in priority order.

  In the example of FIG. 4, “CAN ID” such as “001” and “010” is assigned. In the example of FIG. 4, “CAN ID” is represented by 11 bits, for example, “001” represents “(0) 000 0000 0001”, and “010” represents “(0) 000 0001 0000” in hexadecimal. ing. In the CAN protocol, when “CAN ID” is interpreted as a numerical value, the lower the numerical value, the higher the priority. That is, in the explanatory diagram of FIG. 4, the frame with the “CAN ID” of “001” has the highest priority. In FIG. 4, the priorities are represented by numbers.

  Also, as shown in FIG. 4, each frame is divided into a body system (B) or a control system (C) as an attribute, and indicates an application in which data included in each combination is used. Further, each IOU 5a, 5b, 5c, 5d transmits each frame at a predetermined transmission cycle. As shown in FIG. 4, a predetermined transmission period is assigned to each frame.

  Each of the IOUs 5a, 5b,... Stores the “CAN ID” of data transmitted by itself and information on the transmission cycle in the storage units 51a,. For example, the IOU 5a transmits a frame including body system data from the sensor 1a and control system data from the sensors 1b and 1c, and the “CAN ID” is “020” and “001”. In this embodiment, the IOU 5b transmits frames whose “CAN ID” is “050” and “200”, the IOU 5c transmits frames whose “CAN ID” is “010” and “100”, and the IOU 5d A frame that is “150” is transmitted.

  As described above, the transmission timing of the frames transmitted from the IOUs 5a, 5b,... Is such that the highly related data such as the same system is received by the ECUs 3a, 3b using the data almost simultaneously. It is desirable to be adjusted.

  In the present embodiment, for adjusting the transmission timing, each frame is grouped according to the use (system), transmission cycle, or priority of the included data. The IOUs 5a, 5b,... Store frame grouping information in the storage units 51a,... So that the control units 50a,. Further, in the data of each frame, one specific frame serving as a reference for adjusting the transmission timing is set as a master, and information indicating which frame is the master is stored in the storage units 51a,. Is done. Thereby, the control units 50a,... Of each IOU 5a, 5b,... Recognize which frame is the same group and which frame of each group is the master by referring to the storage units 51a,. Perform processing.

  FIG. 5 is an explanatory diagram showing a content example of grouping information stored in the storage unit 51a of the IOU 5a in the present embodiment. Note that the example shown in FIG. 5 is an example in which the frames shown in FIG. 4 are classified.

  In the example shown in FIG. 5, each frame is classified into groups (1) to (4), and the group (1) has “CAN ID” of “010”, “150”, and “050”. Group (2) has one frame with “CAN ID” of “001”, group (3) has frames with “CAN ID” of “100” and “020”, and group (4) has “ A frame whose “CAN ID” is “200” belongs. The number of the master shown in FIG. 5 indicates the priority order as the master. When the frame having the highest priority is not transmitted due to a failure of the IOUs 5a, 5b,..., Each IOU 5a, 5b,. Recognize a high frame as a master and perform processing.

  The classification into the groups (1) to (4) shown in FIG. 5 is performed as follows. First classify by system. Referring to the content example of FIG. 4, frames with “CAN ID” of “020” and “100” are classified as a body system (B) group, and “CAN ID” is a group of control system (C). Are classified as “001”, “010”, “050”, and “150”, respectively. It should be noted that a frame whose “CAN ID” is “200” including data transmitted to both the body system and the control system is classified into another group.

  Next, for the frames classified into groups of each system, a frame having the shortest transmission cycle in each group is defined as a temporary master. In the body group, a frame whose transmission period is “40 (msec)” and “CAN ID” is “100” is defined as a temporary master. In the control group, a frame whose transmission period is “20 (msec)” and whose “CAN ID” is “010” (or “150”) is defined as a temporary master. In other groups, since one frame belongs, a frame having “CAN ID” “200” is defined as a temporary master.

  Next, for frames classified into each group, frames that are not related to N times (N = 1, 2,...; An integer of 1 or more) of the frame transmission period defined in the temporary master are classified into another group. To do. In the body system group described above, the transmission cycle of the frame whose “CAN ID” is “100” is “200 (msec)”, which is five times the transmission cycle of the temporary master “40 (msec)”. The same group is used as it is. In the control group, the transmission cycle of the temporary master is “20 (msec)”, but the transmission cycle of the frame whose “CAN ID” is “001” is “50 (msec)” and is not N times. , It is classified into another group and itself is defined as a temporary master.

  In this way, classification is performed, and a frame defined as a temporary master is set as a master. If there is a frame that does not belong to any group in the above classification process, the frame is classified as a new group and itself becomes a temporary master.

  In the control system group, there are a plurality of frames with the shortest transmission cycle. In such a case, a frame having a higher frame priority is finally set as a parent frame. In this case, a frame whose “CAN ID” is “010” is defined as a master. Thereby, the classification into groups as shown in FIG. 5 is realized.

  The IOUs 5a, 5b,... Store the grouping information of the frames classified in this way in the storage units 51a,..., And the frames belonging to the same group approach the master frame transmission timing. The transmission timings of the frames are adjusted so that the transmission timings are separated from each other, that is, the time difference is extended.

  FIG. 6 is an explanatory diagram showing an outline of transmission timing adjustment processing by the IOUs 5a, 5b,... In the present embodiment. The upper part of FIG. 6 shows a relationship between the transmission timing of the master frame and other frames belonging to the same group as the frame. In the lower part of FIG. 6, for each of the other frames belonging to the same group as the master frame, the force (F) of approaching the master transmission timing according to the time difference between the frame transmission time and the master frame transmission time is shown. The graph which shows a magnitude | size is shown.

  The transmission timing adjustment by each IOU 5a, 5b,... In this embodiment is adjusted in relation to the master frame transmission timing as shown in FIG. The IOUs 5a, 5b,... Are time differences from the transmission time of the frame transmitted by the master to the transmission time of the master frame belonging to the same group as the frame transmitted by the IOU 5a (= master transmission time−transmission time of the frame transmitted by itself). ) To add the force F obtained by the following equation (1) to the next transmission timing. In equation (1), r is a time difference, and G and g are predetermined constants.

  Thus, the IOUs 5a, 5b,... Have a positive force F when the transmission time of the frame they transmit is before the transmission time of the master frame (upper left arrow in FIG. 6). At the next transmission timing, the force F is added and delayed. On the other hand, when the transmission time of the frame transmitted by itself is later than the transmission time of the master frame (right arrow at the top of FIG. 6), the force F becomes a negative value. It is decremented by F, and it is advanced. In the first embodiment, when the time difference from the transmission time point of the master frame is extremely large, the force F does not work so strongly, but when it is a predetermined time difference, the timing is most strongly approached.

  As described above, the IOUs 5a, 5b,... That transmit other frames belonging to the same group as the master frame are next transmitted by the time corresponding to the magnitude of the force F obtained from the time difference from the transmission time of the master frame. The time difference from the transmission timing of the master frame is shortened by advancing or delaying the transmission timing.

  For example, when the “010” frame that is the master of the group (1) is transmitted from the IOU 5c, the control unit of the IOU 5b that transmits the “050” frame and the IOU 5d that transmits the “150” frame is the master. Is recognized by a notification from the communication unit. Each control unit calculates a time difference from the time point at which it is going to transmit a frame (transmitted if it has already been transmitted), and advances or delays the next transmission timing according to the time difference. , Reduce the time difference.

  FIG. 7 is an explanatory diagram schematically showing a specific example of a result of transmission timing adjustment processing by the IOUs 5a, 5b,... In this embodiment. FIG. 7A shows a time distribution before the adjustment process, and FIG. 7B shows a time distribution at the time of transmission of each frame after the adjustment process. In FIGS. 7A and 7B, the horizontal axis indicates the time axis, and the transmission time of each frame is indicated by an arrow. Note that the transmission time of the master frame is shown on the upper side of the time axis, and the transmission time of the frames other than the master is shown on the lower side.

  In the example shown in FIG. 7A, a frame (hatching arrow) having “CAN ID” “010” is periodically transmitted “20 (msec)” a plurality of times. Although the “150” and “050” frames belong to the same group as the “010” frame, the transmission timings of these frames are “200” frames and “020” frames belonging to other groups. Or close to the transmission timing with the frame of “001”. Similarly, although the frame of “020” is in the same group as the frame of “CAN ID” of “100”, the transmission timing is separated and is close to the frames of other groups. .

  On the other hand, in FIG. 7B, the transmission timing is adjusted so that the transmission timings of the messages “010”, “001”, “100”, and “200” that are the master frames are separated from each other. It is. Thereby, the time difference at the time of transmission is substantially uniform.

  In addition, the transmission timings of the frames having “CAN ID” “150” and “050” are set to the transmission timings of the frame “010” which is the master of the same group (2) by the processing of the control units of the IOUs 5b and 5d. It is adjusted so that frames of the same group are received in close proximity. Also, the frame with “CAN ID” “020” is close to the transmission timing of the master message “100”.

  In this way, by the processing of each IOU 5a, 5b,..., The transmission timing of the frame including the data to be transmitted to the ECUs 3a, 3b, and GW 4 is received collectively by the ECUs 3a, 3b. Adjusted. For example, a frame including control system data having “CAN ID” “010”, “150”, and “050” that belong to the same group and have high relevance is represented by a CAN bus as shown in FIG. 7 are transmitted almost simultaneously. Therefore, the ECU 3b that generates the control data of the actuator 2 using the data can receive the frames including these almost simultaneously. In this way, the data synchronism is increased, the processing load on the ECUs 3a and 3b is reduced, and the transfer of data in the entire in-vehicle control system is made efficient.

  As shown in FIG. 7 (b), frames transmitted from the IOUs 5a, 5b,... Are transmitted together for each group, and the transmission / reception timings of the data of different groups are shifted at substantially equal intervals. Stabilized to be transmitted. Since the CAN bus 7 can transmit only one node, there is a problem that congestion occurs when transmission timing is concentrated, and transmission of frames with low priority is delayed. As shown in FIG. 7B, since each frame is transmitted efficiently, the communication efficiency in the CAN bus 7 is also improved. Due to improved communication efficiency, frames will not be delayed, so there will be no delay for other frames via GW4, and the speed of frame transmission, that is, data transfer in the entire vehicle control system will be improved. There is an effect.

  The disclosed embodiments should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

1a, 1b, 1c, 1d, 1e, 1f, 1g, 1h, 1i, 1j Sensor (device)
2a, 2b, 2c, 2d Actuator (equipment)
3a, 3b ECU (control device)
5a, 5b, 5c, 5d IOU (input / output device)
50a Control unit (adjustment means)
51a storage unit 52a communication unit (communication means)
53a Timekeeping section (detection means)

Claims (8)

A plurality of devices for inputting or outputting data and data output from any of the plurality of devices are connected to a control device that uses or controls any of the devices. In an input / output device comprising means for periodically transmitting to the control device, and means for inputting control data from the control device to any device,
Detection means for detecting a point in time when specific data is transmitted from the control device or another input / output device;
Adjusting means for adjusting the transmission time point of the next data so that the time difference is shortened or extended based on the time difference between the time point detected by the means and the data transmission time point when the data is transmitted by itself. I / O device to perform. Means for storing, for each group, identification information of data divided into a plurality of groups in advance, and identification information of data set as the specific data, one for each group;
When the detecting means detects the time when specific data of the same group as the data transmitted by the adjusting means is detected by the detecting means, the time difference between the detected time and the transmission time of the data to be transmitted is reduced. The input / output device according to claim 1, wherein the next data transmission time point is adjusted. When the data transmitted by the adjusting unit is specific data, and the detection unit detects the transmission time of specific data of a group different from the specific data, the detection time and the transmission time of the data to be transmitted The input / output device according to claim 2, wherein the next data transmission time point is adjusted so that a time difference between the input and the output data is extended. Each data has an attribute associated with it,
The input / output device according to claim 2 or 3, wherein the groups are divided so that data associated with the same attribute becomes the same group. The input / output device according to any one of claims 2 to 4, wherein data having a short transmission cycle in each group is set as the specific data. The input / output device according to any one of claims 2 to 5, wherein each group is divided so as to be composed of data whose transmission cycle is a multiple of the transmission cycle of specific data. 7. The input / output according to claim 2, wherein priority is given to each data, and data having a high priority in each group is set as the specific data. apparatus. A plurality of devices that input or output data; a control device that uses or outputs data output from any of the plurality of devices; and the plurality of devices and the plurality of control devices. A plurality of input / output devices including means for periodically transmitting data output from the device connected to the control device, and means for inputting control data from the control device to any of the devices. In the control system in which the control device and the input / output device are connected to a communication line in a bus shape, and the plurality of control devices control a plurality of devices via the input / output device.
The input / output device is
Detecting means for detecting when specific data is transmitted from the control device or other input / output device to the communication line;
Adjusting means for adjusting the next data transmission time point so that the time difference is shortened or extended based on the time point detected by the means and the time difference between the data transmission time points when the communication means transmits data by itself. Control system characterized by.

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