JP2010173349A - Vehicular traveling control device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a vehicular traveling control device capable of changing the timing of a vehicle control according to a communication load condition on a network transmission line between ECUs. <P>SOLUTION: This vehicular traveling control device includes a first ECU controlling a vehicle operation, a second ECU processing information relating to an obstacle for monitoring a periphery of the vehicle, and a network communication line for communication between the first and second ECUs. The device includes communication load determination means for determining the communication load of the network transmission line, an operation condition mode deciding means for deciding an operation control mode of the vehicle to be executed by the first ECU based on the vehicle periphery information detected by the second ECU, and a timing advancing means for advancing the timing of the operation control in the operation control mode decided by the operation control mode deciding means. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention includes a first ECU that controls vehicle travel, a second ECU that processes a signal from a vehicle periphery monitoring sensor, and a network transmission path for communication between the first and second ECUs. The present invention relates to a vehicular travel control apparatus.

  Conventionally, based on information from a vehicle periphery monitoring sensor (such as a radar device) that detects an inter-vehicle distance between the front vehicle and the host vehicle and information from the vehicle periphery monitoring sensor, a target at a target position is determined from the vehicle speed and the inter-vehicle distance A controller that calculates the target acceleration / deceleration for realizing the vehicle speed, and performs engine output adjustment or brake force adjustment according to the difference between the target acceleration / deceleration and the actual acceleration / deceleration via control of the throttle valve actuator or pressure control valve There is known a vehicular travel control device (see, for example, Patent Document 1).

JP-A-5-310059

  However, when two or more ECUs (controllers) are associated with the network transmission path from the reception of the detection signal of the vehicle periphery monitoring sensor to the application of the drive signal to the actuator, communication on the network transmission path between the ECUs Depending on the load situation, a communication delay may occur and vehicle control may not be realized at the expected timing.

  Accordingly, an object of the present invention is to provide a vehicular travel control apparatus that can change the timing of vehicle control in accordance with the communication load situation on a network transmission path between ECUs.

In order to achieve the above object, according to one aspect of the present invention, a first ECU for controlling vehicle travel, a second ECU for processing information related to obstacles for vehicle periphery monitoring, and the first and second In the vehicle travel control device comprising a network transmission path for communication between the ECUs,
Communication load judging means for judging the communication load of the network transmission path;
Travel control mode determining means for determining a travel control mode of the vehicle to be executed by the first ECU based on vehicle periphery information detected by the second ECU;
Timing advance means that advances the timing of travel control in the travel control mode determined by the travel control mode determination unit when the communication load determined by the communication load determination unit is a high communication load higher than a predetermined standard. The vehicle travel control device is provided.

  ADVANTAGE OF THE INVENTION According to this invention, the vehicle travel control apparatus which can change the timing of vehicle control according to the communication load condition in the network transmission path between ECUs is obtained.

1 is a system configuration diagram showing an overall configuration related to one embodiment of a vehicular travel control apparatus 1 according to the present invention. It is a figure which shows the determination map regarding a relative speed and a relative distance. It is a figure which shows the threshold value (area | region T) regarding a relative advancing direction. It is a figure which shows the time series of the relationship between the deceleration required value after collision unavoidable determination, and a collision position (TTC). The time series of the relationship between the deceleration request value and the collision position (TTC) issued in advance according to this embodiment is shown. It is explanatory drawing which shows the 1st specific example of the advance method of the deceleration request value according to a communication load condition. It is explanatory drawing which shows the 2nd specific example of the advance method of the deceleration request value according to a communication load condition.

  The best mode for carrying out the present invention will be described below with reference to the drawings.

  FIG. 1 is a system configuration diagram showing an overall configuration related to an embodiment of a vehicular travel control apparatus 1 according to the present invention.

  The vehicle travel control device 1 includes a vehicle periphery monitoring sensor 10. The vehicle periphery monitoring sensor 10 may be a radar sensor 12, an image sensor 14 including a CCD camera, or the like. In the case of the radar sensor 12, it may be a millimeter wave radar sensor, a laser radar sensor, an ultrasonic radar sensor, or the like. The scanning method may be electronic or mechanical. The radar sensor 12 and the image sensor 14 may be any sensors for vehicle front monitoring and vehicle side monitoring, or a plurality of sensors are set for vehicle front monitoring and vehicle side monitoring, respectively. May be.

  A DSS # 1ECU 20 is connected to the vehicle periphery monitoring sensor 10 via a periphery monitoring system CAN (controller area network). Sensor information obtained by the vehicle periphery monitoring sensor 10 is supplied to the DSS # 1ECU 20 for processing. The sensor information obtained by the vehicle periphery monitoring sensor 10 may be supplied to the DSS # 1 ECU 20 after undergoing a predetermined process.

  The DSS # 1 ECU 20 (same for other ECUs 24 and the like) is constituted by a microcomputer. For example, a CPU, a ROM for storing a control program, a readable / writable RAM for storing calculation results, a timer, a counter, and an input interface , And an output interface.

  The DSS # 1 ECU 20 detects the relative speed, distance, direction, etc. of the vehicle with respect to obstacles around the vehicle based on sensor information obtained by the vehicle periphery monitoring sensor 10 (including image recognition information obtained from the image sensor). Then, based on this detection result, it is determined whether or not a collision with an obstacle is unavoidable. For example, the DSS # 1 ECU 20 detects and detects that the detected relative distance of the other vehicle exceeds the relative distance threshold line determined with respect to the relative speed as shown in FIG. When the relative traveling direction of the other vehicle falls within the region T shown in FIG. 3 (the angle range defined by the two lines), it is determined that a collision is inevitable with respect to the side collision of the other vehicle with the host vehicle. For the frontal collision and offset collision with other vehicles ahead, the basic concept may be the same except that the region T is different. However, this embodiment can be applied to any collision inevitable determination as long as it determines whether or not the collision between the host vehicle and the obstacle is inevitable. Further, the present embodiment can also be applied to a collision inevitable determination that evaluates the possibility of a collision step by step.

  The DSS # 1 ECU 20 is connected to a seat belt ECU 22 that realizes a seat belt pretensioner function and a G / W • ECU 24 that realizes a gateway function via a bus 42 (hereinafter referred to as a V1 bus 42). When the DSS # 1ECU 20 determines that the collision is unavoidable, the DSS # 1ECU 20 supplies the G / W • ECU 24 with a signal including an operation instruction flag that activates the device that should be operated when the collision is unavoidable and a target value at the time of operation. . Devices that should be activated when the collision unavoidable determination is made may include a seat belt pretensioner, an active door trim, a brake actuator 50, and the like. Here, the brake actuator 50 is assumed as a representative. Therefore, the target value at the time of operation is a deceleration request value (target deceleration) (and corresponding brake pressure request value). In this case, the DSS # 1 ECU 20 calculates the predicted collision time (TTC) based on the sensor information obtained by the vehicle periphery monitoring sensor 10, and reaches the deceleration request value or the predicted collision time at the predicted collision time. The successive deceleration request value is calculated and determined. It should be noted that exchange of signals may be executed at predetermined intervals between the DSS # 1 ECU 20 and the G / W • ECU 24 via the V1 bus 42. In this case, the DSS # 1 ECU 20 includes, for example, a homework for confirming whether or not the communication is successful, together with a signal indicating whether or not the collision is inevitable and a deceleration request value (zero when the collision is unavoidable). A signal may be sent to the G / W • ECU 24 and an answer to the homework from the G / W • ECU 24 may be received to determine whether the communication with the G / W • ECU 24 has been successful.

  A brake ECU 26 for controlling the braking force of the vehicle and a meter ECU 28 for controlling various displays of the meter are connected to the G / W • ECU 24 via a bus 44 (hereinafter referred to as a V2 bus 44). A brake actuator 50 and an alarm buzzer 52 are connected to the brake ECU 26. The G / W • ECU 24 relays the signal from the DSS # 1 ECU 20 and transfers it to the brake ECU 26. The G / W • ECU 24 may transfer the signal from the DSS # 1ECU 20 only when receiving a signal indicating that the collision is inevitable from the DSS # 1ECU20. The brake ECU 26 controls the brake actuator 50 according to the deceleration request value included in the signal from the DSS # 1 ECU 20 so that the deceleration corresponding to the deceleration request value is realized. In addition, when the brake ECU 26 receives information (operation instruction flag) indicating that a collision is inevitable from the DSS # 1 ECU 20, the alarm buzzer 52 issues an alarm for alerting (or an alarm for prompting a brake operation). It may be output.

  FIG. 4 shows a time series of the relationship between the deceleration request value after the collision unavoidable determination and the collision position (TTC). As shown by the solid line, the deceleration request value is time-changed in such a manner that it reaches the final deceleration request value X at the predicted collision time (TTC = 0). When no communication delay occurs, the deceleration request value referenced by the brake ECU 26 follows the waveform shown by the solid line. However, a communication delay occurs depending on the communication load situation. In this case, the deceleration request value referred to by the brake ECU 26 is delayed as shown by the broken line by the communication delay (TTC = B). There may be a case where the final deceleration request value X cannot be reached at time (TTC = 0).

  Therefore, in the present embodiment, when a significant communication delay occurs depending on the communication load situation, as shown by a broken line in FIG. 5, a deceleration request is made in a manner that compensates for the communication delay (TTC = B). The value is advanced. The advance of the deceleration request value may be realized by changing the slope of the time change of the deceleration request value to a steep slope as shown by the broken line in FIG. Alternatively, the advance of the deceleration request value may be realized by calculating the collision prediction time shorter by the communication delay, particularly when a significant communication delay can be predicted depending on the communication load situation.

  Thereby, according to the present embodiment, even when a significant communication delay occurs depending on the communication load situation, the deceleration request value corresponding to the communication delay (that is, the communication load) is executed in advance. The automatic brake function can be activated at a desired timing. That is, the vehicle deceleration can reach the final deceleration request value X at or before the collision prediction time.

  Next, some specific examples of the advance method of the deceleration request value according to the communication load situation will be described.

  FIG. 6 is an explanatory diagram illustrating a first specific example of a method for previously issuing a deceleration request value according to a communication load situation.

  In the example illustrated in FIG. 6, the brake ECU 26 transmits a non-reception flag 2 to the brake ECU 26 when the deceleration request value ID frame cannot be received from the G / W • ECU 24.

  The G / W • ECU 24 transmits the non-reception flag 1 to the brake ECU 26 when the ID frame of the deceleration request value cannot be received from the DSS # 1 ECU 20. Further, when the G / W • ECU 24 receives the non-reception flag 2 from the brake ECU 26, the G / W • ECU 24 determines that the brake ECU 26 has not received the deceleration request value, and transmits the non-reception flag 1 to the brake ECU 26.

  In the example shown in FIG. 6, when the DSS # 1 ECU 20 receives the unreceived flag 1 from the G / W • ECU 24, the G / W • ECU 24 has not received the deceleration request value due to the bus load, or the brake ECU 26. Determines that the deceleration request value has not been received. In this case, the DSS # 1 ECU 20 adds the delay compensation deceleration α to the deceleration request value to be transmitted at the next cycle timing, and transmits the deceleration request value to the G / W • ECU 24 again. In other words, the DSS # 1 ECU 20 corrects (descends) the deceleration request value by the delay compensation deceleration α in the manner shown by the dotted line in FIG. Here, the delay compensation deceleration rate α is calculated from the counter value in the DSS # 1 ECU 20 from the transmission timing of the unreceived deceleration request value to the reception timing of the non-reception flag 1, and according to the calculated time. May be calculated. For example, when the calculated time is longer than a predetermined reference time, the DSS # 1ECU 20 may determine that the communication load is high and add the delay compensation deceleration α according to the calculated time. Alternatively, the DSS # 1ECU 20 determines that the fact that the unreceived flag itself has been received means that the communication load is higher than the predetermined reference, and adds the delay compensation deceleration α corresponding to the calculated time. It is good to do. It is not necessary to add the delay compensation deceleration α to the deceleration request value at once. For example, when it is necessary to prevent a sudden change in the deceleration, the delay compensation deceleration α may be added in a divided manner over a plurality of transmission periods.

  In the example shown in FIG. 6, it is detected that the deceleration request value is not received by the G / W • ECU 24 or the brake ECU 26 by the non-reception flag. Based on the presence / absence and the answer included in the response signal (answer to the homework), it may be detected that the G / W • ECU 24 or the brake ECU 26 has not yet received the deceleration request value.

  FIG. 7 is an explanatory diagram illustrating a second specific example of a method for previously issuing a deceleration request value according to the communication load status.

  In the example illustrated in FIG. 7, it is assumed that the DSS # 1 ECU 20, the G / W • ECU 24, and the brake ECU 26 share the same counter value. That is, it is assumed that the DSS # 1ECU 20, the G / W • ECU 24, and the brake ECU 26 have synchronized counters (clocks).

  In the example shown in FIG. 7, when transmitting the deceleration request value, the DSS # 1ECU 20 superimposes the counter value (DSS # 1ECU counter value) in the DSS # 1ECU 20 at that time on the transmission signal and sends it to the G / W • ECU 24. Send. The G / W • ECU 24 having received this compares the DSS # 1 ECU counter value with the counter value (G / W • ECU counter value) in the G / W • ECU 24 at that time, and the difference (= G / W · ECU counter value−DSS # 1 ECU counter value) is calculated as communication delay time A. Then, the G / W • ECU 24 sends the value obtained by adding the calculated communication delay time A to the G / W • ECU counter value (that is, the DSS # 1ECU counter value) to the brake ECU 26 together with the deceleration request value from the DSS # 1ECU20. Send. Receiving this, the brake ECU 26 calculates the difference between the counter value in the brake ECU 26 at that time and the counter value received from the G / W • ECU 24 (that is, the DSS # 1 ECU counter value), and a delay corresponding to the difference value. The compensation deceleration α is corrected by adding the compensation deceleration α to the deceleration request value. That is, the brake ECU 26 corrects the deceleration request value (advances) with the delay compensation deceleration α in the manner shown by the dotted line in FIG. For example, when the difference value (delay amount) of the calculated counter value is longer than a predetermined reference time, the brake ECU 26 determines that the communication load is high and determines the delay compensation deceleration rate α corresponding to the calculated difference value. When the difference value of the calculated counter value is shorter than the predetermined reference time, it is determined that the communication load is normal or low and the deceleration request value is not corrected. Also good. Alternatively, the brake ECU 26 may add the delay compensation deceleration α corresponding to the calculated difference value of the counter value even when the calculated difference value of the counter value is shorter than the predetermined reference time. It is not necessary to add the delay compensation deceleration α to the deceleration request value at once. For example, when it is necessary to prevent a sudden change in the deceleration, the delay compensation deceleration α may be added in a divided manner over a plurality of transmission periods.

  According to the vehicle travel control device 1 of the present embodiment described above, the following excellent effects can be obtained, among others.

  As described above, depending on the communication load situation in the network transmission path between the DSS # 1 ECU 20, the G / W • ECU 24 and the brake ECU 26, the deceleration request value is transmitted from the DSS # 1 ECU 20 to the brake ECU 26 via the G / W • ECU 24. Even when a significant communication delay occurs, the deceleration request value is corrected according to the communication delay (ie, communication load), so that the automatic brake function can be activated at a desired desired timing.

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

  For example, the embodiment described above relates to control for realizing vehicle deceleration by automatic braking by the brake actuator 50 when a collision is unavoidable. However, the present invention is not limited to this, and at the time of a collision unavoidable determination or at a previous stage. It can also be applied to braking control by engine brake (adjustment of throttle opening). For example, in the braking control by the engine brake, it is only necessary to execute the deceleration request value (the request value of the throttle opening for deceleration) according to the communication load situation in the same manner as in the above-described embodiment.

  In the above-described embodiment, the deceleration request value is corrected from the viewpoint of compensating for the communication delay, but other corrections may be performed in addition to this. For example, the deceleration request value may be corrected according to the vehicle speed, relative speed, and relative position that may change after the collision unavoidable determination, or the deceleration request value is corrected from the viewpoint of compensating for the sensing delay in the vehicle periphery monitoring sensor 10. May be.

  In the above-described embodiment, the communication load status is determined based on whether or not the deceleration request value has not been received. However, the traffic on the V1 bus 42 and the V2 bus 44 may be constantly monitored. In this case, if the traffic on the V1 bus 42 or the V2 bus 44 is equal to or greater than a predetermined value, it is predicted that a deceleration request value will not be received or transmitted, and a deceleration request value is obtained in the same manner as in the above embodiment. It is also possible to execute the preceding.

  In the above-described embodiment, the DSS # 1 ECU 20 processes sensor information obtained by the vehicle periphery monitoring sensor 10 and executes a collision inevitable determination, a deceleration request value calculation, and the like. It is also possible to use information on obstacles (including other vehicles such as a preceding vehicle of the other party of the inter-vehicle communication) obtained through the inter-vehicle communication instead of or in addition to the sensor information obtained in step S2. For example, the relative distance of the other vehicle may be calculated based on the detection result of the vehicle periphery monitoring sensor 10 and / or the position information of the own vehicle and the position information of the other vehicle obtained from the inter-vehicle communication. Similarly, with respect to the relative speed and the relative traveling direction of other vehicles, the vehicle position information history (running vector), the detection result history of the vehicle periphery monitoring sensor 10, and / or other information obtained from the inter-vehicle communication It may be calculated based on a history of vehicle position information (travel vector).

  In the above-described embodiment, the deceleration request value from the DSS # 1 ECU 20 is transmitted to the brake ECU 26 via the G / W • ECU 24 (that is, the two V1 buses 42 and the V2 bus 44). When at least one of the V2 bus 44 is in a high communication load state, a communication delay is likely to occur. Therefore, the present invention is suitable for such a configuration because communication delay can be compensated, but can also be applied to a configuration in which the G / W • ECU 24 is not interposed.

  In the above-described embodiment, the deceleration request value is corrected by adding the delay compensation deceleration rate α. However, as long as the communication delay is compensated, the specific correction manner is arbitrary. For example, equivalently, the deceleration request value may be corrected by multiplying the deceleration request value by a predetermined coefficient (coefficient greater than 1). In this case, the predetermined coefficient may be varied according to the communication load situation.

DESCRIPTION OF SYMBOLS 1 Vehicle travel control apparatus 10 Vehicle periphery monitoring sensor 12 Radar sensor 14 Image sensor 20 DSS # 1ECU
22 seat belt ECU
24 G / W • ECU
26 Brake ECU
28 Meter ECU
42 V1 bus 44 V2 bus 50 Brake actuator 52 Alarm buzzer

Claims (3)

A vehicle comprising: a first ECU that controls vehicle travel; a second ECU that processes information related to obstacles for vehicle periphery monitoring; and a network transmission path for communication between the first and second ECUs In the travel control device for
Communication load judging means for judging the communication load of the network transmission path;
Travel control mode determining means for determining a travel control mode of the vehicle to be executed by the first ECU based on vehicle periphery information detected by the second ECU;
Timing advance means that advances the timing of travel control in the travel control mode determined by the travel control mode determination unit when the communication load determined by the communication load determination unit is a high communication load higher than a predetermined standard. And a vehicle travel control device. The first ECU is a brake control ECU that executes braking force control of the vehicle via a brake actuator as travel control of the vehicle,
The vehicle travel control device according to claim 1, wherein the travel control mode determination unit determines the timing of the braking force control so that a predetermined target deceleration is realized during a predicted collision time with another vehicle. The first ECU performs braking control of the vehicle via the brake actuator based on the target deceleration in the traveling control mode determined by the traveling control mode determining means as the traveling control of the vehicle. A control ECU,
2. The vehicle according to claim 1, wherein the timing advance means realizes the advance by changing a slope of a time change of the target deceleration determined by the travel control mode determining means to a steep slope. Travel control device.

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