JP2012181686A - Vehicular data recording device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a vehicular data recording device that can effectively reduce the necessary capacity for recording data when a predetermined event has occurred.SOLUTION: The value of a time constant of each data is determined. An optimum sampling interval is set based on the value of the time constant. Each data is obtained at the set optimum sampling interval, and recorded on a memory. Thus, it becomes possible that each data is recorded with a necessary degree of accuracy for analysis. As a result, excess data is prevented from being recorded, and lack of necessary data is prevented from occurrence during recording of each data. Thus, the necessary capacity for recording data can be reduced.

Description

  The present invention relates to a vehicular data recording apparatus that records data related to an operation state of an in-vehicle control system that controls a vehicle when a predetermined event occurs.

  For example, Patent Document 1 discloses a data storage device that stores data representing the operating state of a system triggered by the occurrence of a system event. This data storage device includes an analysis target data temporary storage unit that stores analysis target data for a predetermined time or number of acquisitions immediately before, an event occurrence determination unit that determines the occurrence of an event from event occurrence determination data, and the occurrence of an event is determined And a data storage unit that stores data stored in the analysis target data temporary storage unit in association with the event data after a predetermined time.

  As described above, in the apparatus of the cited document 1, by storing the analysis target data in association with the event data, even if the event factor is complex, the analysis target data is associated with the event type, the factor, the condition, and the like. Analysis is possible. Furthermore, since event data itself is stored in association with analysis target data for event factor determination, the amount of data to be stored is reduced, and data can be stored efficiently with a small amount of memory.

Japanese Patent Application Laid-Open No. 2009-3685

  As described above, in the data storage device of Patent Document 1, data to be analyzed in a predetermined period before and after the occurrence of the event is stored in the memory as it is with the occurrence of the event as a trigger. The analysis target data includes detection values detected by various sensors, control data output from various control devices, and the like.

  Here, in particular, detection values detected by various sensors have various temporal change characteristics (hereinafter referred to as time constants) depending on the physical quantity to be detected. For example, in an in-vehicle control system mounted on an electric vehicle or a hybrid vehicle using a motor as a drive source, heat data such as battery temperature, behavior data related to vehicle behavior such as vehicle speed and acceleration, motor drive current, etc. Assume that the electric quantity data is data to be analyzed. In this case, generally, the time for which the calorific value data changes is the longest, and the behavior data and the electric quantity data become shorter in this order. As described above, since the time constant of the detection value of each sensor differs according to the physical quantity to be detected, the accuracy of the detection value required at the time of analysis also differs.

  However, the data storage device of Patent Document 1 does not take into account the required accuracy for each detection value of each sensor, and simply stores the detection value detected by each sensor as it is. For this reason, the data storage device of Patent Literature 1 stores even extra information regarding the detection value of the sensor, which causes a problem of wastefully using the memory capacity. Such a problem may also occur with respect to control data output from the control device.

  The present invention has been made in view of the above points, and by recording each data with the accuracy required at the time of analysis in consideration of the time constant of the data, the recording capacity required for the recording is further reduced. It is an object of the present invention to provide a vehicular data recording apparatus capable of doing so.

In order to achieve the above object, the vehicle data recording device according to claim 1 records data related to the operating state of the in-vehicle control system in a recording means when a predetermined event occurs,
The data related to the operating state of the in-vehicle control system includes two or more types of data expressed by digital values and having different time constants at the time of change,
The recording apparatus includes a recording control unit that determines a time interval for recording data according to a time constant and records the sampled data in the recording unit every time the time interval elapses.

  Since the data recording device according to claim 1 has the above-described configuration, the data recording device records data related to the operation state of the in-vehicle control system at a time interval corresponding to the time constant when each data changes. Can be recorded. For this reason, each data can be recorded with the accuracy required at the time of analysis. As a result, when recording each data, it is possible to prevent unnecessary information from being recorded and, conversely, necessary information from leaking, and to reduce the recording capacity required for data recording.

  Specifically, as described in claim 2, the recording control means determines the time interval for data with a small time constant shorter than the time interval for data with a large time constant. In this way, data with a small time constant at the time of change is recorded at a relatively short time interval, so that the state of change of the data can be accurately grasped. Conversely, data with a large time constant is recorded at relatively long time intervals, but since it changes gradually, the required accuracy can be ensured.

  According to a third aspect of the present invention, two or more types of data having different time constants at the time of change are converted from analog values to digital values by an A / D converter. If the conversion cycle of the D conversion is shorter than the time interval determined for data with a large time constant, the data with a large time constant may be thinned out. This is because if the conversion cycle of the A / D converter is shorter than the time interval determined for data with a large time constant, A / D conversion is performed more frequently than necessary.

  When thinning out data having such a large time constant, as described in claim 4, the A / D converter performs A / D conversion at the same conversion cycle for two or more types of data having different time constants. The recording control means may thin out the digital value after A / D conversion that represents data having a large time constant. In this case, the recording control means records only the digital value remaining without being thinned out of the data having a large time constant in the recording means. According to a fifth aspect of the present invention, the A / D converter samples a digital value by sampling an analog value corresponding to data having a large time constant according to a time interval determined for the data having a large time constant. By converting to, data with a large time constant may be thinned out. According to any of the fourth and fifth aspects of the present invention, data having a large time constant can be recorded on the recording means at appropriate time intervals.

  As described in claim 6, when an abnormality occurs in the operation of a specific in-vehicle device as a predetermined event, the recording control unit performs the operation of the connected in-vehicle device mechanically connected to the specific in-vehicle device. Regarding the related data, it is preferable to record the data on the basis of the abnormality occurrence time. For a connected in-vehicle device that is mechanically connected to a specific in-vehicle device in which an abnormality has occurred, the influence of the abnormal operation in the specific in-vehicle device immediately reaches. For this reason, data related to the operation of the connected in-vehicle device can be used to investigate the cause of the occurrence of the abnormality and to elucidate the influence of the occurrence of the abnormality by recording the data based on the time of occurrence of the abnormality.

  According to a seventh aspect of the present invention, the recording control means detects the time required to change by a predetermined magnitude for each of two or more types of data having different time constants at the time of change, and the detected time May be recorded in the recording means. Even in this case, each data can be recorded at time intervals according to the time constant at the time of change. In this case, the time (time) is recorded in the recording means, but the time represents the time required for each data to change by a predetermined amount. The change of each data can be reproduced.

  According to an eighth aspect of the present invention, the event occurrence detection unit detects that a predetermined event has occurred, and the event occurrence detection unit changes a condition for detecting the occurrence of the predetermined event over time. You may make it let it. The operating state of each part of the vehicle changes with time. Therefore, by changing the condition for detecting the occurrence of a predetermined event with the passage of time, the occurrence of an event corresponding to the predetermined event can be detected with higher accuracy. For example, as described in claim 9, the event occurrence detection means changes the condition for detecting the occurrence of the event so that the frequency of detecting the occurrence of the event falls within a predetermined range regardless of the passage of time. You can do it. In this way, even if the operation state of each part of the vehicle changes due to secular change, the occurrence of the event can be detected with the same accuracy.

  As described in claim 10, two or more types of data having different time constants at the time of change are divided into a plurality of groups based on the approximation of the time constant, and the data is provided for each group, and the data is converted into a digital value. Comprising a plurality of A / D converters having different conversion cycles, and the recording control means records the data converted into digital values by the plurality of A / D converters on the recording means, The conversion period of the A / D converter provided for the group having a large time constant is preferably longer than the conversion period of the A / D converter provided for the group having a small time constant. As a result, the A / D conversion cycle by the A / D converter can be made close in advance to the time interval for recording data, which is determined from the size of the time constant. Therefore, in the A / D converter, it is possible to avoid as much as possible the wasteful A / D conversion process.

  12. Interpolation data calculation for calculating interpolation data obtained by interpolating data of a group having a large time constant in order to obtain data having the same period as data of the group having a small time constant recorded in the recording means. Preferably means are provided. Thereby, for example, the vehicle diagnosis apparatus can easily and accurately analyze the operation state of the in-vehicle control system when an event occurs based on the data acquired from the data recording apparatus.

  As described in claim 12, the in-vehicle control system includes a plurality of electronic control devices, and the data recorded in the recording means is detected by a sensor that detects a physical quantity related to the operating state of the in-vehicle control system. The detection signals including data to be converted into digital values and detected by the sensors are grouped for each group, taken into different electronic control devices, and A provided for the taken-in electronic control device It may be configured to be converted into a digital value by a / D converter. As described above, for each group, an A / D converter and an electronic control unit for handling data included in the group may be individually provided.

It is the block diagram which showed the structure for controlling driving | running | working of the hybrid vehicle with which the vehicle data recording device by embodiment is applied as a block diagram. It is a figure for demonstrating an example of functional arrangement | positioning in each ECU in the case of comprising the control system of a hybrid vehicle by several ECU. It is a flowchart which shows the process which determines generation | occurrence | production of an abnormal event in the recording process for recording data when an abnormal event generate | occur | produces, and manages the log | history. 5 is a flowchart showing a process for setting an optimum sampling interval for each recording target data and performing data recording at the optimum sampling interval in a recording process for recording data when an abnormal event occurs. It is a flowchart which shows the detail of the data recording process in the flowchart of FIG. It is a flowchart which shows the process which one ECU in a vehicle data recording device performs, when a vehicle diagnostic apparatus reads the data recorded on the data recording device for vehicles. It is a flowchart which shows the data recording process in a modification. It is explanatory drawing for demonstrating the relationship between the specific vehicle equipment and connection vehicle equipment in a modification. It is a wave form diagram which shows the example from which the recording of the data relevant to operation | movement of a specific vehicle equipment and the recording of the data relevant to operation | movement of a connection vehicle equipment are synchronized. In a modification, it is a flowchart which shows the process which determines generation | occurrence | production of an abnormal event, and manages the log | history.

  Hereinafter, a vehicle data recording apparatus according to an embodiment of the present invention will be described with reference to the drawings. In the present embodiment, an example in which the vehicle data recording device is applied to a hybrid vehicle having an engine and a motor as a travel drive source of the vehicle will be described, but the application target is a vehicle having only an engine, An electric vehicle having only a motor may be used.

  FIG. 1 is a block diagram showing a configuration for controlling the traveling of a hybrid vehicle as a block diagram. As shown in FIG. 1, the hybrid vehicle includes an engine 11 and a motor generator (MG) 32 as a travel drive source. The MG 32 is disposed on the output shaft of the engine 11. Further, a continuously variable transmission (CVT) 21 is connected to the output shaft of the engine 11.

  The MG 32 operates by receiving power supply from a battery (battery) 51 mounted on the vehicle, and can assist the driving force of the engine 11. Further, when the vehicle decelerates, the MG 32 generates power by rotational driving from the wheel side and charges the battery 51 (energy regeneration). In such a configuration, if a clutch is provided between the engine 11 and the MG 32 so that the engine 11 and the MG 32 can be disconnected, the vehicle can be driven only by the driving force of the MG 32. It becomes.

  The CVT 21 includes a forward / reverse switching mechanism, and generally includes a metal belt that connects an input shaft connected to an output shaft of the engine 11 and an output shaft connected to a drive shaft via a main clutch for starting. This is a continuously variable transmission having a simple structure. In other words, the CVT 21 can change the gear ratio steplessly by changing the pulley width of the pulleys provided on the input shaft and the output shaft, for example, using hydraulic pressure, and changing the winding radius of the metal belt. Is something. However, instead of the CVT 21, an automatic transmission having a plurality of preset gear ratios can be used.

  In addition, although an example in which a so-called parallel system configuration is provided as a hybrid system has been described, hybrid systems using other systems (split system, series / parallel system, etc.) can also be used.

  The brake device 71 can generate a braking force by using, for example, hydraulic pressure or an electric motor regardless of the operation of the brake pedal by the driver. The electric power steering device (EPS) 81 assists the steering force when the driver steers the steering wheel with an electric motor.

  The human machine interface (HMI) 61 means an operation unit operated by a driver for driving a hybrid vehicle, and includes, for example, an accelerator pedal, a brake pedal, a steering wheel, a shift lever, and the like. Each operation amount in these operation units is detected by a sensor or the like and input to the hybrid (HV) ECU 60. However, the detection signal from the sensor may be input to another ECU, or the sensor itself may be communicably connected to the ECU via a communication line.

  The environment vehicle interface (EVI) 62 acquires information about the external environment where the hybrid vehicle is placed. For example, the environment vehicle interface (EVI) 62 acquires a radar device that detects a preceding vehicle or an obstacle, and an image around the vehicle. Applicable to cameras. When this information is obtained, for example, the speed of the host vehicle is adjusted so as to follow the preceding vehicle (adaptive cruise control), or the white line is recognized from the image and the traveling lane defined by the white line is not deviated. As described above, the assist force by the electric power steering device (EPS) 81 can be adjusted (lane keep control).

  In this embodiment, as shown in FIG. 1, the control system of the hybrid vehicle includes an engine ECU 10, a CVTECU 20, an MGECU 30, an energy management ECU 40, a battery ECU 50, an HVECU 60, a brake ECU 70, and an EPS ECU 80. The ECUs are connected via a communication line so that they can communicate with each other. A known in-vehicle LAN (CAN, LIN, etc.) is used for mutual communication between the ECUs.

  An example of functional arrangement in each ECU when a control system of a hybrid vehicle is configured by the plurality of ECUs will be described with reference to FIG.

  The energy management ECU 40 manages the energy consumption of the entire vehicle and bears the function of running the vehicle most efficiently. Specifically, the energy management unit 41 manages the capacity of the battery 51 based on input information from various sensors, and calculates MG torque that can be generated by the MG 32 based on the capacity of the battery 51. To do.

  Regarding the capacity management of the battery 51, the capacity of the battery 51 may fluctuate due to a change in temperature, or the battery 51 may be damaged if the battery temperature rises excessively. For this reason, the energy management unit 41 outputs the battery target temperature to the temperature adjustment unit 42. The temperature adjustment unit 42 includes a cooling unit 43 for driving a cooling device that cools the battery 51 or a heating unit 44 for driving a heating device that raises the temperature of the battery 51 based on the target battery temperature. Use to adjust the temperature of the battery 51.

  In addition, the energy management unit 41 detects a charge level that is a ratio of the remaining charge to the charge capacity of the battery 51, and instructs the charge / discharge adjustment unit 45 to charge / discharge to prevent overcharge or overdischarge of the battery 51. Is output. The charging / discharging adjustment unit 45 outputs a control signal to the plug-in charging unit 52 and the SOC management unit 54 in the battery ECU 50 according to the charging / discharging command, and adjusts the charging level of the battery 51 to an appropriate range. In addition, since the charge capacity of the battery 51 changes according to the deterioration state (SOH) of the battery 51, the SOC management unit 54 uses the information from the SOH management unit 53 to control the charge level of the battery 51.

  For example, the HVECU 60 has a function of inputting information from various sensors such as an accelerator sensor, a brake sensor, a shift position sensor, and a steering sensor and controlling the behavior of the vehicle so as to correspond to the operation of the driver in principle. . Specifically, the vehicle behavior control unit 63 outputs the target acceleration (deceleration) in the front-rear direction to the front-rear behavior adjustment unit 64, and the target acceleration in the left-right direction to the left-right behavior adjustment unit 81 of the EPS ECU 80. By outputting, the behavior of the vehicle is controlled so as to respond to the operation of the driver while stabilizing the behavior of the vehicle.

  The front / rear behavior adjusting unit 64 outputs a target driving torque and a target braking torque to the driving force control unit 65 of the HVECU 60 and the braking force control unit 72 of the brake ECU 70 in order to realize the given target acceleration in the front / rear direction. . The driving force control unit 65 considers the maximum MG torque that can be generated by the MG 32 acquired from the energy management unit 41 in order to achieve the target driving torque most efficiently, while the engine control unit 12 controls the target engine torque and MG control. The target MG torque is given to the unit 33, and the target gear ratio is given to the CVT control unit 22, respectively.

  The engine control unit 12 controls the operating state of the engine 11 by adjusting the throttle valve opening, the fuel supply amount, and the like so that the engine 11 generates the target engine torque based on information such as the engine speed. The MG control unit 33 outputs a drive signal for controlling the operation state of the MG 32 based on information such as the rotation speed and rotation position of the MG 32 so that the MG 32 generates the target MG torque. Output to. The CVT control unit 22 controls the gear ratio of the CVT 21 to the target gear ratio so that the driving torque generated by the engine 11 and the MG 32 is appropriately transmitted to the driving wheels.

  In addition, the braking force control unit 72 gives a target brake braking torque to the brake control unit 73, a target regenerative braking torque to the MG control unit 33, and a target speed ratio to the CVT control unit 22 in order to realize the target braking torque.

  The brake control unit 73 drives the brake fluid pressure and the electric motor so that the brake device 71 generates the target brake braking torque based on information such as the wheel speed of each of the four wheels and the fluid pressure of each of the four wheels. Control. The target brake braking torque is calculated so as to compensate for the shortage when the target regenerative braking torque is insufficient with respect to the target braking torque. In this case, the MG control unit 33 controls the MG 32 to operate as a generator (generator), and the electricity generated by the MG 32 is charged in the battery 51.

  Further, the left / right behavior adjusting unit 82 outputs a target assist torque to the EPS control unit 83 in order to realize the given target acceleration in the left / right direction. The EPS control unit 83 controls the EPS 81 so that the assist torque generated by the EPS 81 becomes the target assist torque based on information such as the drive current of the electric motor.

  Note that the above-described function arrangement in each ECU is merely an example, and the allocation of functions to each ECU can be changed. Further, for example, a plurality of ECUs can be appropriately integrated, for example, the engine 11 and the CVT 21 are controlled by a common ECU.

  As described above, in a hybrid vehicle including the engine 11 and the MG 32 as a travel drive source, for example, the hybrid ECU 60 calculates target torques of the engine 11 and the MG 32 according to the driver's acceleration request (accelerator pedal depression amount). The engine 11 and the MG 32 are output to the ECUs 10 and 30. Then, the ECUs 10 and 30 control the engine 11 and the motor MG 32 according to the calculated target torque. As described above, in a hybrid vehicle, torque for driving the vehicle is controlled by a plurality of ECUs. Therefore, there is a possibility that abnormal behavior of the vehicle may be caused by interference operations of the plurality of ECUs. Increased compared to other vehicles.

  Therefore, some abnormal event (for example, abnormal operation such as sudden change in accelerator depression amount or sudden change in brake depression amount, abnormal behavior such as sudden acceleration, sudden deceleration (rapid stop) and sudden turning of the vehicle, etc.) In the past, it has been possible to record the data related to the operating state of each on-board control system at that time, and to be able to elucidate the cause of the occurrence of the abnormality later. Has been done. Such data includes detection signals detected by various sensors, control data output from various in-vehicle devices and ECUs, and the like.

  However, if the above data is recorded as it is, the memory capacity required to record the data will increase. In particular, in hybrid vehicles, the amount of information to be recorded as data tends to increase, and such a problem appears remarkably.

  Therefore, the vehicular data recording apparatus according to the present embodiment can record necessary data with as little memory capacity as possible. Hereinafter, a configuration for recording data and a recording method in the present embodiment will be described in detail.

  First, in this embodiment, a specific ECU (specifically, hybrid ECU 60), as a rule, inputs a signal from a sensor that outputs a signal to be recorded, and the sensor signal is incorporated into a built-in A / D converter. A description will be given of an example in which data necessary for analysis such as control signals output from other ECUs is collected and recorded together. That is, in this embodiment, the hybrid ECU 60 mainly constitutes a vehicle data recording device.

  However, it does not exclude that an ECU other than the hybrid ECU 60 inputs a signal from a sensor as data necessary for analysis. In this case, the hybrid ECU 60 may receive the sensor signal from another ECU. It is also possible to connect the sensor itself to a communication line and output a signal directly from the sensor to the hybrid ECU 60.

  The memory in which the hybrid ECU 60 records data necessary for analysis is non-volatile, and even if the ignition switch of the vehicle is turned off and the power supply to the hybrid ECU 60 is stopped, the hybrid ECU 60 stores the recorded data. Can be held. The hybrid ECU 60 temporarily records data necessary for analysis in the volatile memory, and writes the data recorded in the volatile memory to the nonvolatile memory at an appropriate timing, for example, when the ignition is off. Anyway.

  The memory of the hybrid ECU 60 is capable of recording data for a first predetermined time, and the hybrid ECU 60 always writes data in its own memory in an infinite loop. This writing is performed at predetermined time intervals determined for each type of data to be written.

  At the same time, the hybrid ECU 60 determines whether an abnormal event has occurred based on event occurrence determination data such as the input sensor signal and target value. When it is determined that an abnormal event has occurred, the hybrid ECU 60 stops data recording when a second predetermined time has elapsed from the determination time. As a result, in the memory of the hybrid ECU 60, data for the first predetermined time-second predetermined time before the occurrence of the abnormal event and data for the second predetermined time after the occurrence of the abnormal event are recorded. .

  The data recorded in the memory of the hybrid ECU 60 includes a sensor signal that detects an operation by the driver. This is because the operation by the driver affects the operating state of each in-vehicle control system. Examples of such sensors include an accelerator pedal sensor that detects the amount of depression of the accelerator pedal, a brake pedal sensor that detects the amount of depression of the brake pedal, a shift position sensor that detects the shift position of the transmission, and the steering angle of the steering wheel. For example, a steering sensor for detecting The data recorded in the memory also includes a sensor signal that detects the behavior of the vehicle that changes under the control of each in-vehicle control system. Examples of such a sensor include a speed sensor that detects the traveling speed of the vehicle, an acceleration sensor that detects acceleration in the front-rear direction and the left-right direction of the vehicle, and a yaw rate sensor that detects a change speed in the rotation direction of the vehicle. .

  In addition, as data recorded in the memory, the temperature of the engine 11, the MG32, and the battery 51, the current value and the rotation speed of the MG32, the charge level (SOC) and the deterioration state (SOH) of the battery 51, the liquid of the brake device Pressure etc. are included. Furthermore, target values and control signals for various control systems of the hybrid vehicle may be included in the data recorded in the memory. For example, the target value and control signal of the electric power steering control system, the target value and control signal of the brake control system, the target value and control signal of the CVT control system, and the target value and control signal of the engine control system. This is because the assist force of the EPS 81, the braking force of the brake device 71, the transmission ratio of the CVT 21, the torque of the engine 11 and the like are changed by the target value and control signal by these control systems.

  Hereinafter, a recording process for recording data when an abnormal event occurs performed in the vehicle data recording apparatus of the present embodiment will be described with reference to the flowcharts of FIGS. In addition, the flowchart of FIGS. 3-5 has shown as an example the recording process in case the sudden change of the accelerator depression amount has arisen as an abnormal event. The processing shown in the flowcharts of FIGS. 3 to 5 is started when the ignition of the vehicle is turned on, and thereafter repeatedly executed at regular intervals.

  In the flowchart of FIG. 3, first, in step S100, a change amount per unit time of the accelerator depression amount is detected. In the subsequent step S110, it is determined whether or not the amount of change in the accelerator depression amount detected in step S100 is equal to or greater than a predetermined value. If “Yes” is determined in step S110, the process proceeds to step S120, and if “No” is determined, the process proceeds to step S130.

  In step S120, it is considered that an abnormal event in which the accelerator operation amount changes suddenly occurs, and an accelerator sudden change event history is set. On the other hand, in step S130, it is determined whether or not the processing of step S120 has been executed in the past and the accelerator sudden change event history has been set. If “Yes” is determined in step S130, the process proceeds to step S140. When a new accelerator sudden change event occurs, the accelerator sudden change event history is recorded so that the data recording process can be performed at that timing. Cancel.

  Next, the process shown in the flowchart of FIG. 4 will be described. In the flowchart of FIG. 4, first, in step S200, it is determined whether or not an accelerator sudden change event history is set. If it is determined “Yes” in step S200, the process of step S210 is executed. If it is determined “No”, the process of step S250 is executed. In step S250, the determination result of the time constant in step S220 described later is cleared, and the determination of the time constant is performed when a new event history is set.

  In step S210, data temporarily recorded in the volatile memory is read and a temporal change amount is detected. In detecting the amount of change over time, for example, the time required for a predetermined change (the time required to increase or decrease to a predetermined ratio or the time required to change by a predetermined value, etc.) The rate of change is detected. In subsequent step S220, the magnitude of the time constant is determined based on the temporal change detected in step S210. In step S230, an optimum sampling interval for recording data is set according to the size of the time constant determined in step S220.

  Here, the time constant is a temporal change characteristic of data and changes variously according to the physical quantity that the data means. For example, in a hybrid vehicle, heat quantity data such as the temperature of the engine 11 and the battery 51, chemical quantity data such as the degree of deterioration (SOH) and charge level (SOC) of the battery 51, hydraulic pressure data such as brake hydraulic pressure, It is assumed that behavior data relating to vehicle behavior such as speed and acceleration, and electrical quantity data such as motor drive current are stored in a memory as data necessary for analysis. In this case, in general, the amount of time for which the calorific data changes is the longest (the time constant is the largest), and the chemical quantity data, the hydraulic pressure data, the behavior data, and the electric quantity data become shorter in this order (the time constants are in order) Smaller). Thus, since the time constant of each data differs according to the physical quantity that each data means, the accuracy of data required at the time of analysis also differs.

  As described above, since the data accuracy required at the time of analysis is different, the optimum data sampling interval for each data is also different. In this respect, in this embodiment, as described above, the time constant size of each data is determined, and the optimum sampling interval is set based on the size of the time constant. Each data can be recorded. As a result, when recording each data, it is possible to prevent unnecessary information from being recorded and, conversely, necessary information from leaking, and to reduce the memory capacity required for data recording.

  The setting of the optimum data sampling interval will be described. The sampling interval for data having a small time constant (that is, the change time is relatively short) is set to a large time constant (that is, the change time is relatively long). It is preferable to determine shorter than the sampling interval for data. As a result, data with a small time constant at the time of change can be recorded at a relatively short time interval, so that the state of change of the data can be accurately grasped. Conversely, data with a large time constant is recorded at relatively long time intervals, but since it changes gradually, the required accuracy can be ensured.

  In the above-described example, the time constant is determined based on the actual change amount of the recording target data, and the optimum sampling interval is set. In this way, for each data, it is possible to set a sampling interval suitable for the actual change characteristics of each data when an abnormal event occurs, and as a result, each data is recorded at an appropriate time interval. Can do. However, since the change characteristics of each data usually fall within a certain range for each data, the optimal sampling interval may be determined in advance for each data.

In the subsequent step S240, a process of recording each data in the memory at an interval corresponding to the sampling interval set as described above is executed.

  If the data to be recorded is converted from an analog value to a digital value by the A / D converter of the HVECU 60, the conversion cycle of the A / D conversion by the A / D converter is the data to be recorded. If the sampling interval is shorter than the sampling interval, the data to be recorded is thinned out. If the conversion period of the A / D converter is shorter than the sampling interval determined for the data to be recorded, A / D conversion is performed more frequently than necessary, and all the converted digital values are recorded. This is because extra data is recorded.

  There are two methods for thinning out data to be recorded. In the first method, the A / D converter of the HVECU 60 performs A / D conversion for the two or more types of data having different time constants in the same conversion cycle, and the sampling interval is longer than the A / D conversion cycle. Regarding data, digital values after A / D conversion are thinned out. In this case, only the digital values remaining without being thinned out among the digital values subjected to A / D conversion are recorded in the memory.

  In the second method, the HVECU 60 switches the data to be A / D converted so that each data is input to the A / D converter at a sampling interval set for each data to be recorded. While controlling a switching circuit such as a multiplexer to be input to the A / D converter. In this way, A / D converted digital values are obtained at intervals corresponding to the sampling intervals set for each data to be recorded, and can be recorded in the memory at appropriate time intervals.

  In the recording process in step S240, each data is classified according to the time constant, and then a data package is created and recorded in the memory. This data package creation and recording process will be described with reference to the flowchart of FIG. In the flowchart of FIG. 5, an example is shown in which the time constant is divided into three types, but the number of divisions is not limited to three.

  In the flowchart of FIG. 5, first, in step S300, the size of the time constant obtained in step S220 is determined for the data to be recorded. Specifically, the time constant is compared with the predetermined values 1, 2, and 3. The relationship between the predetermined values 1, 2, and 3 is predetermined value 1 <predetermined value 2 <predetermined value 3. Therefore, in the determination process of step S300, it is determined whether the time constant is greater than the predetermined value 1 and less than or equal to the predetermined value 2, greater than the predetermined value 2 and less than or equal to the predetermined value 3, or greater than the predetermined value 3. .

  When it is determined that the time constant is greater than the predetermined value 1 and less than or equal to the predetermined value 2, the process proceeds to step S310, and the data package 1 in which similar time constant data is collected is created and recorded.

  Similarly, if it is determined that the time constant is greater than the predetermined value 2 and less than or equal to the predetermined value 3, the process proceeds to step S320, and the data package 2 in which similar time constant data is collected is recorded and recorded. If it is determined that the time constant is greater than the predetermined value 3, the process proceeds to step S330, and the data package 3 in which data of similar time constants are collected is recorded.

  In this way, by creating and recording a data package in which data having similar time constants are collected and recorded, for example, even when a part of the system configuration as a target for data recording is changed, Changes in the configuration of the vehicle data recording apparatus can be minimized.

  When data is stored in a memory, recording is performed in units of a predetermined number of bits (8, 16, 32 bits, etc.). When each data package is created, the length of the combination of two or more data is If the number of bits is less than a predetermined number, it is preferable to combine two or more pieces of data. Thereby, the memory capacity for recording the data package can be compressed.

  In step S340, it is determined whether the recording process for all data to be recorded has been completed. If the processing has not been completed for all data, the processing from step S300 is repeated.

  By reading out and analyzing the data recorded in this way by the vehicle diagnostic apparatus, it can be used to elucidate the cause of the occurrence of the abnormality. That is, the vehicle diagnostic device analyzes the operating state of the in-vehicle control system when an abnormal event occurs from the data read from the vehicle data recording device, and diagnoses the cause of the abnormality.

  The flowchart of FIG. 6 shows processing executed by the HVECU 60 in order to output the data recorded in the memory of the HVECU 60 to an external vehicle diagnostic apparatus. The HVECU 60 outputs the recorded data when an external vehicle diagnostic device is connected to the vehicle data recording device.

In the flowchart of FIG. 6, first, in step S400, data recorded in the memory is read for each type of data. In subsequent step S410, linear interpolation data is created based on the read data. That is, since the read data is recorded at predetermined time intervals for each data type, the above-described linear interpolation data can be created by interpolating between the data with a straight line. Note that the interpolation data is not limited to linear interpolation, and complementary data using curves may be obtained in consideration of the change characteristics of each data.

In step S420, the data at the same time is calculated from the linearly interpolated data, and the calculated data at the same time is output in step S430. The data at the same time is calculated at regular intervals and output to the vehicle diagnostic apparatus.

  Thereby, the vehicle diagnostic apparatus can easily analyze the operation state of the in-vehicle control system when the abnormal event occurs from the data read from the vehicle data recording apparatus. In addition, by interpolating the data in this way, it is possible to output a data set that matches the data recorded at the shortest time interval even when the time intervals at which the respective data are recorded are different.

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

  For example, in the above-described embodiment, data acquired at the sampling interval determined for each data is recorded in the memory. However, for each piece of data to be recorded, the time required to change by a predetermined magnitude may be detected, and the detected time may be recorded in the memory. Even in this case, each data can be recorded at time intervals according to the time constant at the time of change. In other words, in this case, the time (time) is recorded in the memory, but the time represents the time required for each data to change by a predetermined amount. The state of data change can be reproduced.

  A process for recording the time required for each data to change by a predetermined amount will be described with reference to the flowchart of FIG.

  In step S500 of the flowchart of FIG. 7, it is determined whether or not an event history is set, as in step S200 of the flowchart of FIG. If “Yes” is determined in step S200, an event has occurred and data recording is required, and thus the process proceeds to step S510. In step S510, data temporarily recorded in the volatile memory is read, and a temporal change amount of the recording target data is detected.

  In the subsequent step S520, it is determined whether or not the temporal change amount of the recording target data detected in step S510 has reached a predetermined value. This predetermined value may be common to each data, or may be set individually. In this determination process, if it is determined that the temporal change amount of the recording target data has reached a predetermined value, the process proceeds to step S530. In step S530, the time when the amount of change reaches a predetermined value is recorded in the memory. The time may be a time measured by a free running timer of the ECU, or may be an elapsed time from the start of data recording when an abnormality occurs. In step S540, it is determined whether or not data recording for a predetermined time, which is the time for which data should be recorded, is completed. If not completed, the process returns to step S510. The process of the flowchart ends.

  In the embodiment described above, in principle, a specific ECU inputs a signal from a sensor that outputs a signal to be recorded, and A / D converts the sensor signal by a built-in A / D converter. Furthermore, data necessary for analysis such as control signals output from other ECUs are collected and recorded together.

  However, for example, among the data to be recorded, sensor signals that detect physical quantities related to the operating state of the in-vehicle control system are divided into a plurality of groups based on the approximation of the time constant of each sensor signal. You may make it input into different ECU for every. In this case, the sensor signal input to each ECU is converted into a digital value by an A / D converter provided in each ECU and recorded in a memory in each ECU.

  Then, the conversion cycle of the A / D converter provided for the group having a large time constant is set longer than the conversion cycle of the A / D converter provided for the group having a small time constant. As a result, the A / D conversion cycle by the A / D converter can be made close in advance to the time interval for recording data, which is determined from the size of the time constant. Therefore, in the A / D converter, it is possible to avoid as much as possible the wasteful A / D conversion process.

  However, as described above, when A / D conversion is performed by the A / D converter of each ECU, the time timing at which the sensor signal is A / D converted may be shifted for each group. Therefore, it is preferable to record the time information at the time when the A / D conversion is performed in the memory. In this way, it is possible to grasp the temporal relationship between the sensor signals of different groups while converting the data into digital values using separate A / D converters provided in each ECU. .

  Further, each ECU individually records data to be recorded such as a sensor signal, a target value, and a control signal in a memory of each ECU, and one ECU operates abnormally in a specific in-vehicle device. Is detected as a predetermined event, the one ECU records data related to the operation state of the in-vehicle device in which the operation abnormality has occurred, based on the operation abnormality detection time. Further, when there is a connected in-vehicle device that is mechanically connected to a specific in-vehicle device in which an operation abnormality has occurred, the one ECU outputs an operation abnormality occurrence signal to the ECU that controls the connected in-vehicle device. To do. Then, the ECU that has received the output of the operation abnormality occurrence signal may start recording data related to the operation state of the connected in-vehicle device with reference to the reception timing.

  For example, as shown in FIG. 8, in the hybrid vehicle, the engine 11 and the MG 32 are mechanically coupled. For this reason, for example, when some operation abnormality occurs in the engine 11, the influence immediately reaches the MG 32. Therefore, in addition to data on the specific in-vehicle device (engine 11) in which the operation abnormality has occurred, data related to the operation of the connected in-vehicle device (MG32) is recorded in the memory of each ECU, thereby investigating the cause of the occurrence of the abnormality. It can be useful for elucidating the effects of the occurrence of abnormalities.

  Then, as shown in FIG. 9, the ECU that has received the output of the operation abnormality occurrence signal starts recording data related to the operation state of the connected in-vehicle device (MG32) with reference to the reception timing. This makes it possible to synchronize the recording of data related to the operation of the specific in-vehicle device (engine 11) and the recording of data related to the operation of the connected in-vehicle device (MG32) while recording in different ECUs. . Accordingly, it is possible to investigate the cause by using data actually detected instead of the interpolation data, so that the cause can be investigated more correctly.

  Before an abnormal operation occurs in a specific in-vehicle device, the ECU that controls the specific in-vehicle device and the ECU that controls the connected in-vehicle device each independently store data temporarily. That is, the data to be recorded is asynchronous before the occurrence of the abnormality but is synchronized after the occurrence of the abnormality.

  Further, since the state of charge of the battery 51 changes due to the operation of the MG 32, as a result, when the operation abnormality of the engine 11 occurs, the operation state of the battery 51 also changes indirectly. Therefore, when an operation abnormality occurs in the engine 11, an operation abnormality occurrence signal may be output to the battery ECU 50 that controls the battery 51, and data related to the operation of the battery 51 may be recorded. However, in this case, since the abnormal operation of the engine 11 does not immediately affect the operation of the battery 51, it is not necessary to forcibly synchronize and record data as shown in FIG.

  In the above-described embodiment, it is detected as occurrence of a predetermined event that the amount of change in the accelerator depression amount is equal to or greater than a predetermined value. Here, the operating state of each part constituting the vehicle to be controlled including the accelerator pedal changes more or less due to aging. Therefore, if a certain threshold value is used to detect the occurrence of a predetermined event, the detection accuracy of the occurrence of the predetermined event may be lowered due to secular change.

  Therefore, conditions such as a threshold for detecting the occurrence of a predetermined event may be changed with the passage of time. As a result, even when a secular change occurs, the occurrence of an event corresponding to a predetermined event can be accurately detected.

  As a specific example in which the detection condition for occurrence of a predetermined event is changed with the passage of time, the occurrence of an event is detected so that the frequency of occurrence of the event falls within a predetermined range as shown in the flowchart of FIG. You may make it change conditions. That is, in step S650 of the flowchart of FIG. 10, the occurrence frequency of the predetermined event is determined, and it is determined whether or not the occurrence frequency is within a predetermined range. If the occurrence frequency is outside the predetermined range, in step S660, the threshold for determining the occurrence of the predetermined event is changed so that the occurrence frequency is within the predetermined range. In this way, even if the operation state of each part of the vehicle changes due to aging, it is possible to accurately detect that a predetermined event has occurred.

  Note that the processing from steps S600 to S640 in the flowchart of FIG. 10 is substantially the same as the processing from steps S100 to S140 in the flowchart of FIG.

  The occurrence frequency of the predetermined event is defined as the number of occurrences per predetermined time or predetermined distance with respect to the time and distance traveled by the vehicle. Furthermore, the predetermined range compared with the occurrence frequency may be determined based on the occurrence frequency of a predetermined event in a predetermined period after the vehicle starts to be used.

10 Engine ECU
11 engine 20 continuously variable transmission ECU
21 continuously variable transmission 30 motor generator ECU
32 Motor generator 40 Energy management ECU
50 Battery ECU
51 battery 60 hybrid ECU
70 Brake ECU
71 Brake device 80 Electric power steering ECU
81 Electric power steering device

Claims (12)

A vehicle data recording device that records data related to the operation state of the in-vehicle control system in a recording means when a predetermined event occurs,
The data related to the operating state of the in-vehicle control system includes two or more types of data that are expressed by digital values and have different time constants at the time of change,
A vehicle data recording comprising: a recording control unit that determines a time interval for recording the data according to the time constant, and records the sampled data in the recording unit at every elapse of the time interval. apparatus.   2. The vehicular data recording apparatus according to claim 1, wherein the recording control unit determines a time interval for data having a small time constant shorter than a time interval for data having a large time constant. Two or more types of data having different time constants at the time of change are converted from analog values to digital values by an A / D converter,
If the conversion period of A / D conversion by the A / D converter is shorter than the time interval determined for data having a large time constant, the data having a large time constant is thinned out. The vehicular data recording apparatus according to claim 2. The A / D converter performs A / D conversion at the same conversion cycle for two or more types of data having different time constants.
The recording control means thins out the digital value after A / D conversion, which represents data having a large time constant, and records only the digital value remaining without being thinned out in the recording means, whereby the data having the large time constant is recorded. 4. The vehicle data recording apparatus according to claim 3, wherein thinning is performed.   The A / D converter samples the analog value corresponding to the data with the large time constant and converts it into a digital value according to the time interval determined for the data with the large time constant, thereby converting the time constant 4. The vehicular data recording apparatus according to claim 3, wherein the data is thinned out.   When an abnormality occurs in the operation of a specific in-vehicle device as the predetermined event, the recording control means relates to data related to the operation of the first in-vehicle device mechanically connected to the specific in-vehicle device. 3. The vehicle data recording apparatus according to claim 1, wherein data is recorded based on the abnormality occurrence time.   The recording control means detects a time required to change by a predetermined amount for each of two or more types of data having different time constants at the time of change, and uses the detected time as the data as the recording means. The vehicular data recording apparatus according to claim 1, wherein the vehicular data recording apparatus records the vehicular data.   An event occurrence detection unit for detecting that the predetermined event has occurred, wherein the event occurrence detection unit changes a condition for detecting the occurrence of the predetermined event with the passage of time. Item 9. The vehicle data recording device according to any one of Items 1 to 8.   9. The event occurrence detection unit changes the condition for detecting the occurrence of the event so that the frequency of detecting the occurrence of the event falls within a predetermined range regardless of the passage of time. The vehicle data recording device described. Two or more types of data having different time constants at the time of change are divided into a plurality of groups based on the approximation of the time constants, provided for each group, and a conversion cycle when converting the data into digital values is provided. A plurality of different A / D converters,
The recording control means records data converted into digital values by the plurality of A / D converters on the recording means,
The conversion period of the A / D converter provided for the group having a large time constant is longer than the conversion period of the A / D converter provided for the group having a small time constant. The vehicle data recording device according to claim 1 or 2.   Interpolation data calculation means for calculating interpolation data obtained by interpolating data of the group having a large time constant is obtained in order to obtain data having the same period as the data of the group having a small time constant recorded in the recording means. The vehicle data recording device according to claim 10. The in-vehicle control system is composed of a plurality of electronic control devices,
The data includes data that is detected by a sensor that detects a physical quantity related to the operating state of the in-vehicle control system and converted into a digital value,
The detection signals detected by the sensors are grouped for each group, taken into different electronic control devices, and converted into digital values by A / D converters provided for the taken-in electronic control devices. The vehicular data recording apparatus according to claim 10 or 11, wherein the vehicular data recording apparatus is used.