Speed ​​reduction control device

Abstract

The present invention provides a deceleration control device that performs deceleration control when the vehicle makes a right or left turn at an intersection, reducing the possibility of a following vehicle rear-ending the vehicle while also reducing the possibility of the driver feeling uncomfortable with the deceleration control. [Solution] When the vehicle makes a right or left turn at an intersection, if there are no following vehicles, the deceleration control device starts deceleration control at a first timing. On the other hand, if there are following vehicles, the deceleration control device determines whether the normal start condition is met, which is met when at least the first condition that the following vehicle makes a right or left turn at the intersection is met. If the normal start condition is not met, the deceleration control device starts deceleration control at a second timing earlier than the first timing, and if the normal start condition is met, it starts deceleration control at the first timing.

Description

Technical Field

[0001] The present invention relates to a deceleration control device that starts deceleration control for decelerating a host vehicle at a predetermined timing when the host vehicle makes a right or left turn at an intersection.

Background Art

[0002] Conventionally, a deceleration control device that starts deceleration control when a host vehicle makes a right or left turn at an intersection has been known. On the other hand, for example, the deceleration control device described in Patent Document 1 (hereinafter referred to as the "conventional device") determines whether a following vehicle deceleration condition that the following vehicle is decelerating is satisfied when a situation where deceleration of the host vehicle is necessary is detected in front of the host vehicle. When the following vehicle deceleration condition is not satisfied, the conventional device turns on a warning lamp for the following vehicle, and when the following vehicle deceleration condition is satisfied, the conventional device does not turn on the warning lamp.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

[0004] When the host vehicle makes a right or left turn at an intersection, it is desirable to start deceleration control earlier in order to reduce the possibility of a following vehicle colliding with the host vehicle. On the other hand, if deceleration control is started earlier, the driver of the host vehicle may feel uncomfortable with the deceleration control. Therefore, it is desirable that deceleration control is started earlier when the possibility of a following vehicle colliding with the host vehicle is high, and deceleration control is started at a normal timing when the possibility of a following vehicle colliding with the host vehicle is low.

[0005] The conventional device determines whether to turn on or off a warning lamp based on the state of the following vehicle, and does not determine whether to start deceleration control earlier based on the state of the following vehicle.

[0006] This invention was made to address the aforementioned problems. Specifically, one of the objectives of this invention is to provide a deceleration control device that reduces the possibility of a following vehicle rear-ending the vehicle while also reducing the possibility of the driver feeling uncomfortable with the deceleration control.

[0007] The deceleration control device of the present invention (hereinafter referred to as "the present invention device") starts deceleration control to decelerate the vehicle at a predetermined timing when the vehicle makes a right or left turn at an intersection located in front of the vehicle (step 315 "Yes") (step 340 "Yes", steps 500 to 595). The aforementioned deceleration control device is If there is no following vehicle behind the vehicle (step 325 "No"), the deceleration control is started at the first timing (step 330), If the aforementioned following vehicle exists (step 325 "No"), it is determined whether the normal start condition is met, which is met when at least the first condition that the following vehicle makes a right or left turn at the intersection is met (step 350), If the above normal start conditions are not met (step 350 "No"), the deceleration control is started at a second start timing earlier than the first timing (step 355). If the above normal start conditions are met (step 350 "Yes", step 365 "Yes"), the deceleration control is started at the first timing (step 330). A deceleration control device configured as follows.

[0008] When the normal starting conditions are met, the following vehicle is more likely to slow down to turn right or left at an intersection than when the normal starting conditions are not met. In other words, when the normal starting conditions are not met, the following vehicle is less likely to slow down than when the normal starting conditions are met. Therefore, when the normal starting conditions are not met, the following vehicle is more likely to rear-end your vehicle when you slow down than when the normal starting conditions are met.

[0009] Therefore, if the normal starting conditions are not met, the device 10 starts deceleration control at a second timing earlier than the first timing. As a result, if there is a high probability of a rear-end collision with a following vehicle, deceleration control is started earlier, allowing the driver of the following vehicle to know that their vehicle is slowing down at an earlier stage. This reduces the possibility of a rear-end collision with the following vehicle. Furthermore, if the possibility of a rear-end collision with a following vehicle is low, the start of deceleration control is not advanced, thus reducing the possibility of the driver of the vehicle feeling something is wrong with the deceleration control. [Brief explanation of the drawing]

[0010] [Figure 1] This is a schematic system configuration diagram of a deceleration control device according to an embodiment of the present invention. [Figure 2] This is an explanatory diagram of an example of operation of a deceleration control device according to an embodiment of the present invention. [Figure 3] Figure 1 is a flowchart of the start determination routine executed by the CPU of the ECU. [Figure 4] This diagram illustrates the normal deceleration profile and the early deceleration profile. [Figure 5] Figure 1 is a flowchart of the deceleration control routine executed by the CPU of the ECU. [Modes for carrying out the invention]

[0011] A deceleration control device 10 (hereinafter referred to as "this device 10") according to an embodiment of the present invention is applied to the vehicle VA and comprises the components shown in Figure 1. In this specification, "ECU 20" is an electronic control device mainly comprising a microcomputer. ECU 20 is also referred to as a control unit, controller, and computer. The microcomputer includes a CPU (processor), ROM, RAM, and interface (I / F), etc. The functions realized by ECU 20 may be realized by multiple ECUs.

[0012] The front camera 22 acquires forward image data by photographing the scenery in front of the vehicle VA. The rear camera 24 acquires rear image data by photographing the scenery behind the vehicle VA. The ECU 20 acquires forward image data and rear image data from the front camera 22 and the rear camera 24, respectively. The turn signal lever 26 is located near the steering wheel (not shown) of the vehicle VA. For example, when the turn signal lever 26 is operated downwards, the right turn signal 26A located on the right side of the vehicle VA illuminates, and when the turn signal lever 26 is operated upwards, the left turn signal 26B located on the left side of the vehicle VA illuminates. The driver activates the right turn signal 26A when turning the vehicle VA to the right, and the left turn signal 26B when turning the vehicle VA to the left.

[0013] The vehicle speed sensor 28 measures the vehicle speed Vs, which represents the speed of the vehicle VA. The acceleration sensor 30 measures the acceleration G of the vehicle VA. Note that acceleration G in the direction of acceleration of the vehicle VA is a positive value, and acceleration G in the direction of deceleration of the vehicle VA is a negative value. Note that negative acceleration G is sometimes expressed as "deceleration Gd". The ECU 20 acquires the measured values ​​from these sensors 28 and 30.

[0014] The storage device 32 stores map data. The map data includes the locations (latitude and longitude) of roads and intersections. The GNSS (Global Navigation Satellite System) receiver 34 receives signals from multiple satellites and determines the current position (latitude and longitude) of the vehicle VA based on the received signals. The vehicle-to-vehicle communication interface 36 is an interface for communicating with other vehicles.

[0015] The powertrain actuator 40 modifies the driving force generated by the vehicle's drive system (e.g., internal combustion engine and / or electric motor). The brake actuator 42 modifies the braking force applied to the vehicle's VA.

[0016] <Deceleration control> The ECU 20 determines whether an intersection IN (see Fig. 2) exists based on the forward image data. When the intersection IN exists, the ECU 20 determines whether the host vehicle VA makes a right or left turn based on the lighting states of the right blinker 26A and the left blinker 26B. When the host vehicle VA makes a right or left turn, the ECU 20 determines whether the distance D (see Fig. 2) between the host vehicle VA and the intersection IN is less than or equal to the start distance Dst. When the distance D is less than or equal to the start distance Dst, the ECU 20 starts the deceleration control. In the deceleration control, the ECU 20 decelerates the host vehicle VA so that the vehicle speed Vs matches the predetermined target vehicle speed Vtgt at a target point before a predetermined distance Dend from the intersection IN.

[0017] (Outline of operation) When the host vehicle VA makes a right or left turn at the intersection IN and there is no following vehicle VB, the ECU 20 sets the start distance Dst to the first start distance Dst1 (see Fig. 2). The following vehicle VB is another vehicle that travels in the same lane as the host vehicle VA and is located within a predetermined recognition distance behind the host vehicle VA. When there are a plurality of such other vehicles, the other vehicle closest to the host vehicle VA is specified as the following vehicle VB. The ECU 20 determines whether the following vehicle VB exists based on the rear image data. The recognition distance may be a variable value that becomes longer as the vehicle speed Vs increases.

[0018] When the host vehicle VA makes a right or left turn at the intersection IN and the following vehicle VB exists, the ECU 20 determines whether the normal start condition is satisfied. Specifically, the ECU 20 determines that the normal start condition is satisfied when the following first condition and second condition are satisfied. First condition: The following vehicle VB makes a right or left turn at the intersection IN. Second condition: The direction of the right or left turn of the host vehicle VA (hereinafter referred to as the "first right / left turn direction") and the direction of the right or left turn of the following vehicle VB (hereinafter referred to as the "second right / left turn direction") match.

[0019] For example, the ECU 20 determines whether either the right or left blinker of the following vehicle VB is lit based on the rear image data. When either the right or left blinker of the following vehicle VB is lit, the ECU 20 determines that the following vehicle VB will turn right or left at the intersection IN (that is, it determines that the first condition is satisfied).

[0020] The ECU 20 identifies the first right / left turn direction based on the lighting states of the right blinker 26A and the left blinker 26B. The ECU 20 identifies the lighting states of the right and left blinkers of the following vehicle VB based on the rear image data, and identifies the second right / left turn direction based on the lighting states.

[0021] When both the first condition and the second condition are satisfied, that is, when the normal start condition is satisfied, the following vehicle VB is likely to decelerate for a right / left turn in the same direction as the host vehicle VA, so the possibility of the following vehicle VB colliding with the host vehicle VA is low. Therefore, when the normal start condition is satisfied, there is no need to start the deceleration control at an earlier timing than usual, so the ECU 20 sets the start distance Dst to the first start distance Dst1.

[0022] When the first condition is not satisfied, that is, when it cannot be determined whether the host vehicle VA goes straight through the intersection IN or makes a right / left turn at the intersection IN, the possibility that the following vehicle VB decelerates is lower than when the normal start condition is satisfied. For this reason, the possibility that the following vehicle VB collides with the host vehicle VA when the first condition is not satisfied is higher than when the normal start condition is satisfied.

[0023] On the other hand, when the second condition is not satisfied, although the following vehicle VB may decelerate for a right / left turn in a direction different from the host vehicle VA, it may overtake the host vehicle VA or change lanes. When the following vehicle VB overtakes the host vehicle VA or changes lanes, it is highly likely not to decelerate. For this reason, the possibility that the following vehicle VB decelerates when the second condition is not satisfied is lower than when the normal start condition is satisfied.

[0024] Therefore, if the normal start conditions are not met, the ECU20 starts deceleration control earlier than usual. Specifically, if the normal start conditions are not met, the ECU20 sets the start distance Dst to "the second start distance Dst2, which is longer than the first start distance Dst1".

[0025] If the normal starting conditions are not met, the starting distance Dst is set to the second starting distance Dst2, and deceleration control is initiated at an earlier timing (second timing) than when the normal starting conditions are met (first timing). As a result, the driver of the following vehicle VB can be notified earlier that their own vehicle VA is decelerating, thus reducing the possibility of the following vehicle VB rear-ending their own vehicle VA.

[0026] Furthermore, when the normal start conditions are met, the start distance Dst is set to the first start distance Dst1, so that deceleration control is started at the normal timing (first timing). This reduces the possibility that the driver of the vehicle VA may feel uncomfortable with the deceleration control.

[0027] (Example of operation) An example of the operation of this device 10 will be explained with reference to Figure 2. Based on the forward image data, ECU20 determines that there is an intersection to enter. Furthermore, because the left turn signal 26B is illuminated, ECU20 identifies that the first right / left turn direction is left.

[0028] The ECU20 determines, based on the rear image data, that a following vehicle VB exists. Furthermore, based on the rear image data, the ECU20 determines that neither the right nor the left turn signal of the following vehicle VB is illuminated. Therefore, the ECU20 determines that the following vehicle VB will not turn right or left at the intersection. Consequently, the ECU20 determines that the normal start condition is not met and sets the start distance Dst to the second start distance Dst2. In the example shown in Figure 2, the ECU20 starts deceleration control when the distance D becomes less than or equal to the "start distance Dst set in the second start distance Dst2".

[0029] (Specific operation) The CPU of ECU20 executes the routines shown in the flowcharts in Figures 3 and 5 at predetermined intervals.

[0030] <Start Determination Routine> When the appropriate time arrives, the CPU starts processing from step 300 in Figure 3, and the processing proceeds to step 305. In step 305, the CPU determines whether the execution flag Xexe is "0".

[0031] The execution flag Xexe is set to "1" when deceleration control is being performed and to "0" when deceleration control is not being performed. The execution flag Xexe is set to "0" in the initialization routine. The CPU executes the initialization routine when the ignition key switch (not shown) of the vehicle VA is changed from the off position to the on position.

[0032] If the execution flag Xexe is "0", the CPU determines "Yes" in step 305, and the process proceeds to step 310. In step 310, the CPU determines whether or not an intersection IN exists based on the forward image data.

[0033] If there is no intersection IN, the CPU determines "No" in step 310, and the process proceeds to step 395. In step 395, the CPU terminates this routine.

[0034] If an intersection IN exists, the CPU determines "Yes" in step 310, and the process proceeds to step 315. In step 315, the CPU determines whether the vehicle VA will make a right or left turn based on the illumination status of the right turn signal 26A and the left turn signal 26B. Specifically, the CPU determines that the vehicle VA will make a right or left turn if either the right turn signal 26A or the left turn signal 26B is illuminated.

[0035] If the vehicle VA does not make a right or left turn, deceleration control does not need to be performed. In this case, the CPU determines "No" in step 315, and the process proceeds to step 395.

[0036] If the vehicle VA is to make a right or left turn, the CPU determines "Yes" in step 315 and executes steps 320 and 325.

[0037] Step 320: The CPU determines the first right / left turn direction and the first starting distance Dst1. In detail, if the right turn signal 26A is illuminated, the CPU determines that the first right or left turn direction is to the right. If the left turn signal 26B is illuminated, the CPU determines that the first right or left turn direction is to the left. Furthermore, assuming that the vehicle VA decelerates under the following constraints 1 and 2, the CPU identifies the distance required for the vehicle speed Vs to match the target vehicle speed Vtgt when the vehicle VA reaches the target point as the first starting distance Dst1. Constraint Condition 1: At the start of deceleration control, acceleration G decreases at a predetermined slope Jpd until it matches the minimum acceleration Gmin. The minimum acceleration Gmin is the maximum deceleration that can occur during deceleration control. The minimum acceleration Gmin may also be referred to as the maximum deceleration or a constant value. Constraint condition 2: At the end of deceleration control, acceleration G increases at a predetermined slope Jpd until the acceleration G becomes "0" from the minimum acceleration Gmin.

[0038] Step 325: The CPU determines whether or not a following vehicle VB exists based on the rear image data.

[0039] If there is no following vehicle VB, the CPU determines "No" in step 325 and executes steps 330 through 340. Step 330: The CPU sets the starting distance Dst to the first starting distance Dst1. Step 335: The CPU is set to use the deceleration profile.

[0040] The normal deceleration profile will be explained with reference to Figure 4. During deceleration control, the ECU20 obtains the target acceleration Gtgt by referring to either the normal deceleration profile or the early deceleration profile. The normal deceleration profile and the early deceleration profile define the relationship between distance D and target acceleration Gtgt.

[0041] In a typical deceleration profile, the target acceleration Gtgt gradually decreases at a rate of Jpd as the distance D decreases, from "0" when the distance D is the first starting distance Dst1 to the minimum target acceleration Gmin. In other words, the target deceleration gradually increases at a rate of Jpd as the distance D decreases, from "0" to the maximum target deceleration. When the distance D becomes distance Da, the target acceleration Gtgt coincides with the minimum target acceleration Gmin, and thereafter the target acceleration Gtgt is maintained at the minimum target acceleration Gmin. Subsequently, the target acceleration Gtgt gradually increases at a rate of Jpd as the distance D decreases, such that the target acceleration Gtgt becomes "0" when the distance D is a predetermined distance Dend.

[0042] Step 340: The CPU determines whether distance D is less than or equal to the starting distance Dst.

[0043] If distance D is longer than the starting distance Dst, the CPU determines "No" in step 340, and the process proceeds to step 395.

[0044] If distance D is less than or equal to the starting distance Dst, the CPU determines "Yes" in step 340, and the process proceeds to step 345. In step 345, the CPU sets the execution flag Xexe to "1". After that, the process proceeds to step 395.

[0045] If a following vehicle VB exists when the process proceeds to step 325, the CPU determines "Yes" in step 325, and the process proceeds to step 350. In step 350, the CPU determines, based on the rear image data, whether the following vehicle VB is making a right or left turn.

[0046] If the following vehicle VB is going straight, or if it is not possible to determine whether the following vehicle VB is making a right or left turn, the first condition is not met, and therefore the normal start condition is not met. For example, if the CPU cannot determine from the rear image data whether the turn signal of the following vehicle VB is on, it determines that it is not possible to determine whether the following vehicle VB is making a right or left turn. If the following vehicle VB is going straight, or if it is not possible to determine whether the following vehicle VB is making a right or left turn, the CPU determines "No" in step 350 and executes steps 355 and 360.

[0047] Step 355: The CPU sets the starting distance Dst to the second starting distance Dst2. The CPU obtains the second starting distance Dst2 by adding the margin distance Dm to the first starting distance Dst1. The margin distance Dm may be a predetermined fixed distance, or it may be a variable distance that increases as the vehicle speed Vs increases.

[0048] Step 360: The CPU sets the deceleration profile to use the early deceleration profile. As shown in Figure 4, the target acceleration Gtgt in the early deceleration profile, after the distance D becomes less than or equal to the distance Da, is the same as in the normal deceleration profile. In the early deceleration profile, deceleration control begins when the distance D becomes the "second starting distance Dst2, which is longer than the first starting distance Dst1". Therefore, the slope at which the target acceleration Gtgt decreases from the second starting distance Dst2 to the distance Da in the early deceleration profile is smaller than the slope Jpd of the normal deceleration profile. In detail, the target acceleration Gtgt decreases by a slope Jpd1 from the second starting distance Dst2 to the distance Db, and by a slope Jpd2 from the distance Db to the distance Da. Slopes Jpd1 and Jpd2 are smaller than slope Jpd. Furthermore, slope Jpd2 is smaller than slope Jpd1.

[0049] Furthermore, the area under the target acceleration Gtgt is equal for both the normal deceleration profile and the early deceleration profile.

[0050] Thus, in the early deceleration profile, the slope of the target acceleration Gtgt at the start of deceleration control is smaller compared to the normal deceleration profile. As a result, the deceleration of the vehicle VA at the start of deceleration control is gradual, so the distance between the vehicle VA and the following vehicle VB does not decrease rapidly. This reduces the possibility of the following vehicle VB rear-ending the vehicle VA. Furthermore, it increases the likelihood that the driver of the following vehicle VB will notice the deceleration of the vehicle VA earlier.

[0051] After the CPU executes step 360, the process proceeds to step 340.

[0052] If the following vehicle VB makes a right or left turn when the process proceeds to step 350 (i.e., the first condition is met), the CPU determines "Yes" in step 350, and the process proceeds to step 365. In step 365, the CPU determines whether the first right or left turn direction and the second right or left turn direction are the same.

[0053] If the first right / left turn direction and the second right / left turn direction are different, the second condition is not met, and therefore the normal start condition is not met. In this case, the CPU determines "No" in step 365, and the process proceeds to step 355. On the other hand, if the first right / left turn direction and the second right / left turn direction are the same, both the first and second conditions are met, and therefore the normal start condition is met. In this case, the CPU determines "Yes" in step 365, and the process proceeds to step 330. As a result, the start distance Dst is set to the first start distance Dst1, and the deceleration profile used is set to the normal deceleration profile.

[0054] If the execution flag Xexe is "1" when the process proceeds to step 305, the CPU determines "No" in step 305, and the process proceeds to step 395.

[0055] <Deceleration control routine> When the appropriate time arrives, the CPU starts processing from step 500 in Figure 5, and the processing proceeds to step 505. In step 505, the CPU determines whether the execution flag Xexe is "1".

[0056] If the execution flag Xexe is "0", the CPU determines "No" in step 505, and the process proceeds to step 595. In step 595, the CPU terminates this routine.

[0057] If the execution flag Xexe is "1", the CPU determines "Yes" in step 505 and executes steps 510 and 515. Step 510: The CPU obtains the distance D based on the forward image data. Step 515: The CPU determines whether the termination condition for deceleration control is met. In detail, the CPU determines that the termination condition is met when distance D matches a predetermined distance Dend, or when the vehicle VA has completed its right or left turn. The CPU also determines that the vehicle VA has completed its right or left turn when the turn signal switches from illuminated to off.

[0058] If the termination condition is not met, the CPU determines "No" in step 515 and executes steps 520 and 525. Step 525: The CPU obtains the target acceleration Gtgt by applying the distance D to the deceleration profile. Step 530: The CPU controls the powertrain actuator 40 and the brake actuator 42 so that the acceleration G matches the target acceleration Gtgt. The process then proceeds to step 595.

[0059] If the termination condition is met when the process proceeds to step 515, the CPU determines "Yes" in step 515, and the process proceeds to step 530. In step 530, the CPU sets the execution flag Xexe to "0". After that, the process proceeds to step 595.

[0060] As explained above, if a following vehicle VB is present and the normal starting conditions are not met, the device 10 starts the deceleration control earlier than usual. This reduces the possibility of the following vehicle VB rear-ending the vehicle VA, while also reducing the possibility of the driver feeling uncomfortable with the deceleration control.

[0061] <First variation> In the above embodiment, if both the first and second conditions are met, the ECU 20 determines that the normal start condition is met. In this modified example, if the first condition is met, the ECU 20 determines that the normal start condition is met even if the second condition is not met.

[0062] As described above, if the second condition is not met, the following vehicle VB may overtake vehicle VA without slowing down or change lanes. However, if the second condition is not met, the following vehicle VB may also slow down in order to turn right or left in a different direction from vehicle VA. For this reason, the likelihood of the following vehicle VB slowing down when the first condition is met but the second condition is not met is considered higher than when the first condition is not met.

[0063] Therefore, in this modified example, if the first condition is met, regardless of whether the second condition is met or not, the ECU 20 determines that the normal start condition is met and starts deceleration control at the normal timing. If the first condition is not met, the ECU 20 determines that the normal start condition is not met and starts deceleration control at an earlier timing than usual.

[0064] In view of the above embodiments and this modified example, the normal starting condition can be described as a condition that is met when at least the first condition is met.

[0065] <Second variation> In this modified example, the ECU20 determines whether the vehicle VA should make a right or left turn at an intersection IN based on pre-set route information. The route information is information about the route that the vehicle VA should travel, and includes information about which intersection IN to turn at.

[0066] The ECU 20 automatically illuminates the turn signal corresponding to the right or left turn when the vehicle VA approaches an intersection IN where it will make a right or left turn. More specifically, the ECU 20 obtains the illumination distance Dli by adding a predetermined distance Dp to the "starting distance Dst set in step 330 or step 355 shown in Figure 3". When the distance D becomes less than or equal to the illumination distance Dli, the ECU 20 automatically illuminates the turn signal corresponding to the right or left turn. Therefore, in this modified example, if the normal starting conditions are not met, the ECU 20 illuminates the turn signals corresponding to the right or left turn earlier than when the normal starting conditions are met. This eliminates the need for the driver to operate the turn signal lever 26.

[0067] <Third variation> In the above embodiment, the ECU 20 determined whether or not an intersection exists based on forward image data, but is not limited to this. For example, the ECU 20 may refer to map data and determine whether or not an intersection exists within a predetermined distance in the direction of travel of the vehicle VA from the "current position of the vehicle VA identified by the GNSS receiver 34".

[0068] <Fourth variation> In the above embodiment, the ECU 20 determines whether the following vehicle VB will make a right or left turn at the intersection IN based on the rear image data, and identifies the second right or left turn direction based on the rear image data, but is not limited to this.

[0069] For example, the ECU 20 may determine whether the following vehicle VB will make a right or left turn at the intersection entrance by communicating with the following vehicle VB, and then identify the second right or left turn direction. Specifically, when the following vehicle VB makes a right or left turn (for example, when the turn signal lever is operated), it transmits right or left turn data regarding the direction of the turn. The right or left turn data includes the current position of the following vehicle VB. When the ECU 20 receives the right or left turn data, it identifies the position of the "vehicle that transmitted the right or left turn data" relative to its own vehicle VA based on the current position included in the right or left turn data. If this position is located within a predetermined recognition distance behind the own vehicle VA, the ECU 20 determines that the "vehicle that transmitted the right or left turn data" is the following vehicle VB, and determines that the following vehicle VB will make a right or left turn at the intersection entrance based on the right or left turn data, and also identifies the second right or left turn direction based on the right or left turn data.

[0070] Furthermore, the ECU20 may receive position data from vehicles surrounding its own vehicle VA via vehicle-to-vehicle communication and determine whether or not a following vehicle VB exists based on the position data, similar to the identification of the following vehicle VB described above.

[0071] Furthermore, if the lane in which its own vehicle VA is traveling is a lane designated for right or left turns, the ECU20 may determine that the following vehicle VB is going to make a right or left turn. In this case, the ECU20 considers the first right or left turn direction and the second right or left turn direction to be the same.

[0072] The ECU20 detects road surface arrows on the lane in which the vehicle VA is traveling based on forward image data. If the road surface arrows permit travel in either the right or left direction, the ECU20 determines that the vehicle VA is traveling in a lane designated for right or left turns. This allows the ECU20 to determine whether the following vehicle VB will make a right or left turn at the intersection and identify the direction of the second right or left turn, even if information about the following vehicle VB cannot be obtained.

[0073] Furthermore, if the arrow-type traffic signal TL (see Figure 2) installed at intersection IN is red and the right-turn or left-turn arrow signal is illuminated, the ECU 20 may determine that the following vehicle VB is making a right or left turn and specify the second right or left turn direction as "the direction of the illuminated arrow signal."

[0074] In the example shown in Figure 2, the arrow signal TL is illuminated in red and the left-turn arrow signal is lit, so the ECU20 determines that the following vehicle VB is making a right or left turn and identifies the second right or left turn direction as "left".

[0075] This allows us to determine whether the following vehicle VB will make a right or left turn at the intersection based on the information provided by the arrow-type traffic signal TL, and to identify the direction of the second right or left turn. Therefore, even if information about the following vehicle VB cannot be obtained, we can still determine whether the following vehicle VB will make a right or left turn at the intersection and identify the direction of the second right or left turn.

[0076] <Fifth variation> In the above embodiment, the ECU 20 started deceleration control when the distance D became less than or equal to the starting distance Dst, but instead of distance D, the arrival time T until the vehicle VA reaches intersection IN may be used. That is, the ECU 20 may start deceleration control when the arrival time T becomes less than or equal to the starting time Tst.

[0077] This device 10 is applicable to vehicles such as engine-powered vehicles, hybrid vehicles, plug-in hybrid vehicles, fuel cell vehicles, and electric vehicles. Furthermore, this device 10 is also applicable to autonomous vehicles. [Explanation of Symbols]

[0078] 10...Driving assistance system, 22...Front camera, 24...Rear camera, 26...Turn signal lever, 40...Powertrain actuator, 42...Brake actuator.

Claims

1. In a deceleration control device that initiates deceleration control to slow down the vehicle at a predetermined timing when the vehicle makes a right or left turn at an intersection located in front of the vehicle, The aforementioned deceleration control device is If there is no following vehicle behind the vehicle, the deceleration control is started at the first timing. If the aforementioned following vehicle exists, it is determined whether the normal start condition is met, which is met when at least the first condition that the following vehicle makes a right or left turn at the intersection is met. If the above normal start conditions are not met, the deceleration control is started at a second timing earlier than the first timing. If the above normal start condition is met, the deceleration control is started at the first timing. A deceleration control device configured as follows.

2. In the deceleration control device according to claim 1, The deceleration control device is configured to determine that the normal start condition is met when the first condition is met and the second condition is met, which is that the direction of the vehicle's right or left turn matches the direction of the following vehicle's right or left turn. Speed ​​reduction control device.

3. In the deceleration control device according to claim 2, The deceleration control device is configured to determine that the normal start condition is met when the vehicle is traveling in a lane designated for right or left turns, or when the light indicator of the arrow-type traffic signal installed at the intersection is red and the right or left turn arrow light is illuminated. Speed ​​reduction control device.

4. In the deceleration control device according to claim 1, The aforementioned deceleration control device is In the deceleration control described above, the driving state of the vehicle is controlled so that the deceleration of the vehicle matches the target deceleration. From the start of the deceleration control until the target deceleration reaches a constant value, the target deceleration is increased at a predetermined rate. When the deceleration control is started at the second timing, the inclination is reduced compared to when the deceleration control is started at the first timing. A deceleration control device configured as follows.

5. In the deceleration control device according to claim 1, The aforementioned deceleration control device is If the system determines that the vehicle should make a right or left turn at the intersection based on pre-set route information relating to the route the vehicle should travel, the system will illuminate the turn signal for the right or left turn. If the above-mentioned normal start conditions are not met, the timing of the turn signal illumination will be earlier than when the above-mentioned normal start conditions are met. A deceleration control device configured as follows.

Images