JP2017128178A - Vehicular travel control device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a vehicular travel control device that can suppress unnecessary acceleration and deceleration.SOLUTION: A vehicular travel control device 100 comprises: detecting units 10, 11a and 11b; an interrupting vehicle determining unit 63; a first target acceleration calculating unit 30; a second target acceleration calculating unit 71; a target acceleration arbitrating unit 72; and a travel controlling unit 82. When an inter-vehicle distance between its own vehicle and a vehicle ahead is below a predetermined first set inter-vehicle distance and the inter-vehicle distance or a direct distance between its own vehicle and the vehicle ahead is below a threshold defined based on precision of the detecting units, the interrupting-vehicle determining unit 63 determines the vehicle ahead as a predicted interrupting vehicle which is predicted to interrupt between its own vehicle and a vehicle to be followed. A second target acceleration calculating unit 71 calculates a target acceleration for dealing with interruption so that an inter-vehicle distance between its own vehicle and the predicted interrupting vehicle is equal to a predetermined second set inter-vehicle distance.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a vehicular travel control apparatus that performs inter-vehicle distance control.

  Conventionally, a vehicular travel control device that performs inter-vehicle distance control and constant speed travel control is known. The vehicle travel control device performs inter-vehicle distance control for controlling the vehicle speed of the host vehicle so that the set inter-vehicle distance is maintained with respect to the preceding vehicle when the preceding vehicle exists in the own lane, and when the preceding vehicle does not exist. Constant speed running control is performed to maintain the vehicle speed of the host vehicle at the set vehicle speed. In relation to such a vehicular travel control device, for example, a technique described in Patent Document 1 is known.

JP 2004-114906 A

  However, in the conventional vehicular travel control device, unnecessary acceleration / deceleration occurs when inter-vehicle distance control is performed on a vehicle in an adjacent lane that may be interrupted between the host vehicle and the preceding vehicle.

  This invention is made | formed in view of such a condition, The objective is to provide the traveling control apparatus for vehicles which can suppress unnecessary acceleration / deceleration.

  In order to solve the above problems, a vehicle travel control apparatus according to an aspect of the present invention detects a tracking target vehicle that travels in front of the host vehicle and a front side vehicle that travels in front of the host vehicle. The inter-vehicle distance between the detection unit and the host vehicle and the front side vehicle is equal to or less than a predetermined first set inter-vehicle distance, and the inter-vehicle distance or the linear distance between the host vehicle and the front side vehicle is the detection unit. An interruption vehicle determination unit that determines that the front side vehicle is an expected interruption vehicle that is expected to interrupt between the host vehicle and the tracking target vehicle when the vehicle is below a threshold set based on the accuracy of A first target acceleration calculating unit that calculates a target acceleration for tracking so that an inter-vehicle distance between the host vehicle and the tracking target vehicle is the first set inter-vehicle distance; and the host vehicle and the predicted interrupting vehicle Predetermined distance between vehicles A second target acceleration calculating unit that calculates the target acceleration for interruption corresponding to the second set inter-vehicle distance, and a smaller one of the target acceleration for tracking and the target acceleration for interruption is selected as the target acceleration after arbitration A target acceleration arbitration unit; and a travel control unit that controls the driving force and the braking force of the host vehicle so that the acceleration of the host vehicle approaches the target acceleration after the arbitration.

  According to this aspect, the deceleration control is performed on the front side vehicle that is relatively close to the host vehicle and has a great influence on the host vehicle, and the deceleration control is not performed on the front side vehicle that is relatively far from the host vehicle. Therefore, unnecessary acceleration / deceleration in which acceleration is performed again after unnecessary deceleration can be suppressed.

  According to the present invention, unnecessary acceleration / deceleration can be suppressed.

1 is a block diagram of a vehicle travel control apparatus according to a first embodiment. It is a figure explaining the setting method of the threshold value which concerns on 1st Embodiment. It is a flowchart which shows the process performed by the interruption vehicle determination part of FIG. It is a figure explaining operation | movement of the traveling control apparatus for vehicles of FIG. It is a figure explaining operation | movement of the vehicle travel control apparatus which concerns on 2nd Embodiment.

(First embodiment)
FIG. 1 is a block diagram of a vehicle travel control apparatus 100 according to the first embodiment. The vehicle travel control apparatus 100 may be referred to as ACC (Adaptive Cruise Control).

  The vehicle travel control apparatus 100 includes a front radar sensor (detection unit) 10, front side radar sensors (detection units) 11a and 11b, an inter-vehicle control ECU (Electronic Control Unit) 20, a brake ECU 80, an engine ECU 81, A travel control unit 82 and an HMI (Human Machine Interface) output device 83 are provided.

  The front radar sensor 10 is arranged at the center of the front end portion of the vehicle such as a front bumper or a front grille of the vehicle, emits a millimeter wave at a predetermined angle around the front of the vehicle, and is reflected by a target existing in this range. Receive reflected waves.

  The front side radar sensors 11a and 11b are disposed, for example, offset left and right at the front end of the vehicle such as a front bumper or a front grill of the vehicle. The front side radar sensor 11a for the left side emits a millimeter wave at a predetermined angle around the left front of the vehicle, and receives a reflected wave reflected by a target existing in this range. The front side radar sensor 11b for the right side emits a millimeter wave at a predetermined angle centered on the right front side of the vehicle, and receives a reflected wave reflected by a target existing in this range.

  The front radar sensor 10 and the front side radar sensors 11a and 11b each detect the position and relative velocity of the target by analyzing the received reflected wave. Specifically, the front radar sensor 10 and the like detect the relative speed in the front-rear direction, the relative speed in the horizontal direction, the position in the front-rear direction, and the position in the horizontal direction with respect to the host vehicle. Thereby, the front radar sensor 10 and the front side radar sensors 11a and 11b can detect the tracking target vehicle that travels in front of the host vehicle and the front side vehicle that travels in front of the host vehicle. The tracking target vehicle is a vehicle in front of the own vehicle on the own lane, and is the vehicle closest to the own vehicle.

  The inter-vehicle control ECU 20 performs inter-vehicle distance control based on the detection results of the front radar sensor 10 and the front side radar sensors 11a and 11b. The inter-vehicle control ECU 20 includes a first target acceleration calculation unit 30, a surrounding environment detection unit 40, a host vehicle course estimation unit 50, an interrupt determination unit 60, and an acceleration arbitration unit 70.

  The first target acceleration calculation unit 30 determines that the inter-vehicle distance between the host vehicle and the tracking target vehicle is based on the relative speed in the front-rear direction of the tracking target vehicle detected by the front radar sensor 10 and the position in the front-rear direction. The tracking target acceleration is calculated so as to be the distance. Specifically, the first target acceleration calculation unit 30 follows the target acceleration for tracking based on the corrected relative speed in the front-rear direction of the vehicle to be followed, which will be described later, and the position in the front-rear direction of the vehicle to be tracked after correction. Is calculated. The target acceleration for tracking is a positive or negative value. The first set inter-vehicle distance is set by the driver. The first target acceleration calculation unit 30 calculates the target acceleration for constant speed travel so that the vehicle speed of the host vehicle becomes the set vehicle speed when there is no tracking target vehicle.

  The surrounding environment detection unit 40 detects the surrounding environment of the vehicle based on the detection results of the front radar sensor 10 and the front side radar sensors 11a and 11b. The surrounding environment detection unit 40 includes a moving object determination unit 41, an oncoming vehicle determination unit 42, and an identical object determination unit 43.

  The moving object determination unit 41 determines whether the target continues to move for a predetermined time or more based on the relative speed of the target. The oncoming vehicle determination unit 42 determines whether the target is an oncoming vehicle based on the relative speed of the target. The same object determination unit 43 determines whether the target detected by the front radar sensor 10 and the targets detected by the front side radar sensors 11a and 11b are the same, and if they are the same, integrates them. To do.

  The own vehicle route estimation unit 50 estimates the own vehicle route according to the road shape. The road shape can be extracted from map data used in a navigation system (not shown). The own vehicle course estimating unit 50 calculates the radius of curvature of the curved road with reference to the own vehicle from the own car course. Instead of the host vehicle course estimation unit 50, using a white line detection sensor that detects a pair of white lines indicating a lane in which the host vehicle is traveling by imaging a road, or a yaw rate sensor that detects the yaw rate of the host vehicle, The curvature radius of the curved road may be calculated.

  The interrupt determination unit 60 includes a correction unit 61, an interrupt position determination unit 62, an interrupt vehicle determination unit 63, an interrupt probability calculation unit 64, and an interrupt determination result calculation unit 65.

  Based on the radius of curvature calculated by the host vehicle course estimation unit 50, the correction unit 61 detects the relative speed in the front-rear direction and the lateral direction of the target including the tracking target vehicle and the front side vehicle detected by the front radar sensor 10 or the like. Correct the relative speed in the direction, the position in the horizontal direction and the position in the front-rear direction.

  The interrupt position determination unit 62 determines whether or not the interrupt position where the vehicle in the adjacent lane is expected to come in is ahead of the host vehicle.

  The interrupting vehicle determination unit 63 is based on the surrounding environment of the vehicle detected by the surrounding environment detection unit 40 and the determination result of the interruption position determination unit 62, and from the detected target, An oncoming vehicle, a vehicle whose interrupt position is behind the host vehicle, and a preceding vehicle are excluded, and the remaining target is a front side vehicle.

  When the inter-vehicle distance between the host vehicle before correction and the front side vehicle is equal to or less than a predetermined first set inter-vehicle distance and the inter-vehicle distance is equal to or less than a predetermined threshold, Then, it is determined as an expected interruption vehicle that is expected to be interrupted between the own vehicle and the vehicle to be followed. The inter-vehicle distance between the host vehicle before correction and the front side vehicle is equal to the position in the front-rear direction of the front side vehicle before correction. The threshold is set in advance based on the accuracy of the front radar sensor 10 and the front side radar sensors 11a and 11b. A method for setting the threshold will be described later.

  The interruption probability calculation unit 64 calculates an interruption probability that the front side vehicle, which is an expected interruption vehicle, interrupts between the own vehicle and the tracking target vehicle based on the lateral position and the lateral relative speed of the front side vehicle. It calculates periodically with a predetermined cycle. Specifically, the interrupt probability calculation unit 64 calculates an interrupt probability based on the corrected lateral position of the front side vehicle and the corrected lateral relative speed of the front side vehicle. The interruption probability calculation unit 64 basically calculates the interruption probability higher as the corrected lateral position of the front side vehicle is closer, and as the corrected lateral relative speed of the front side vehicle is higher, High interrupt probability is calculated. By using the corrected lateral position of the front side vehicle and the corrected lateral relative speed of the front side vehicle, a more accurate interrupt probability even when driving on a curved road with a relatively small radius of curvature Can be obtained.

  The interrupt determination result calculation unit 65 performs a first-order lag filter process on the calculated interrupt probability, and calculates an interrupt determination result from the interrupt probability subjected to the first-order lag filter process. The time constant of the first-order lag filtering process may be set as appropriate through experiments or the like so as to eliminate fluctuations in interrupt probability and sudden changes. The interrupt determination result is expressed as a probability, and is, for example, 0% (no probability), 50% (medium probability), or 100% (high probability). The interrupt determination result may be either 0% or 100%, or any of four or more values.

  There is no particular limitation on the method of calculating the interrupt determination result from the interrupt probability in which the first-order lag filter processing has been performed. For example, when the first threshold value and the second threshold value are set, and the interrupt probability for which the first-order lag filter processing has been performed is less than the first threshold value, the interrupt determination result is 0%, and the first threshold value and the second threshold value are less than the second threshold value The interrupt determination result may be set to 50%, and the interrupt determination result may be set to 100% when the second threshold value is exceeded. Further, the interrupt determination result calculation unit 65 may change the first threshold value and the second threshold value according to the immediately previous interrupt determination result to provide hysteresis. As a result, even if the interrupt probability for which the first-order lag filter processing has been performed fluctuates small in the vicinity of the first threshold value or the second threshold value, it is possible to prevent the interrupt determination result from changing.

The acceleration mediation unit 70 includes a second target acceleration calculation unit 71 and a target acceleration mediation unit 72. When the interruption determination result is equal to or greater than a predetermined value, the second target acceleration calculation unit 71 determines that the inter-vehicle distance between the own vehicle and the predicted interruption vehicle is predetermined based on the relative speed in the front-rear direction of the predicted interruption vehicle and the position in the front-rear direction. The target acceleration for interruption is calculated according to the interruption determination result so as to be the second set inter-vehicle distance. Specifically, the second target acceleration calculation unit 71 calculates the target acceleration for interruption based on the corrected relative speed in the front-rear direction of the predicted interrupting vehicle and the corrected position of the predicted interrupting vehicle in the front-rear direction. To do. Accordingly, the inter-vehicle distance control can be performed more accurately even while traveling on a curved road having a relatively small radius of curvature. The target acceleration for interrupt handling is a positive or negative value.
When the interruption determination result is less than the predetermined value, the second target acceleration calculation unit 71 does not calculate the target acceleration for interruption.

  The predetermined value is, for example, 50%, which is a value corresponding to the medium probability. When the interruption determination result is 50%, acceleration suppression is indicated, and the second target acceleration calculation unit 71 calculates the target acceleration for interruption within a range obtained by closing the throttle. When the interruption determination result is 100%, it represents braking permission, and the second target acceleration calculation unit 71 calculates the target acceleration for interruption within a range obtained by closing the throttle and applying the brake. Thereby, when the interruption determination result is 50%, the deceleration is smaller than when the interruption determination result is 100%. Therefore, when the interruption determination result is 50%, it is difficult to decelerate rapidly, so that the driver's uncomfortable feeling can be suppressed.

  The second set inter-vehicle distance may be set by a driver or may be determined in advance. The second set inter-vehicle distance may be equal to or different from the first set inter-vehicle distance.

  The target acceleration arbitration unit 72 selects a smaller one of the tracking target acceleration and the interrupt-response target acceleration as the post-arbitration target acceleration.

  The brake ECU 80 and the engine ECU 81 control the travel control unit 82 based on the post-arbitration target acceleration. The traveling control unit 82 controls the driving force and the braking force of the host vehicle so that the acceleration of the host vehicle approaches the target acceleration after the arbitration.

  The HMI output device 83 is provided in the passenger compartment, and notifies the driver by display or voice when the interrupt determination result is 50% or 100%.

  FIG. 2 is a diagram for explaining a threshold setting method according to the first embodiment. FIG. 2 shows the host vehicle Ca and a preceding vehicle Cb traveling in front of the host vehicle Ca. For example, it is assumed that the detection accuracy of the front radar sensor 10 is higher than the detection accuracy of the front side radar sensors 11a and 11b. The error in the lateral direction between the position PA of the preceding vehicle Cb detected by the front radar sensor 10 and the actual position PB of the preceding vehicle Cb is x1 (m). The lateral error between the position PC of the preceding vehicle Cb detected by the front side radar sensor 11b and the actual position PB of the preceding vehicle Cb is x2 (m). x2 is longer than x1. Therefore, the distance L at which the maximum allowable error x2 is obtained is set as a threshold value. For example, the threshold L may be a distance L at which the maximum allowable error x2 is about 1.3 m based on a general vehicle width.

  FIG. 3 is a flowchart showing processing performed by the interrupted vehicle determination unit 63 of FIG. The processing in FIG. 3 is periodically performed at a predetermined cycle. First, it is determined whether or not a front side vehicle is present (S1). If it does not exist (N in S1), the current process is terminated. When the front side vehicle exists (Y in S1), it is determined whether the inter-vehicle distance d between the host vehicle and the front side vehicle is equal to or smaller than the threshold value Dth1 and the first set inter-vehicle distance Dfw (S2). When the condition of S2 is not satisfied (N of S2), the current process is terminated. When the condition of S2 is satisfied (Y of S2), the front side vehicle is determined as the predicted interruption vehicle (S3).

  FIG. 4 is a diagram for explaining the operation of the vehicle travel control apparatus 100 of FIG. As shown in FIG. 4, the host vehicle Ca keeps the first set inter-vehicle distance Dfw and follows the tracking target vehicle Cb. It is assumed that any of the front side vehicles C1 to C3 is traveling in the adjacent lane.

  When the front side vehicle C1 having the inter-vehicle distance d1 exists, the front side vehicle C1 is not determined as the predicted interrupt vehicle because the inter-vehicle distance d1> the first set inter-vehicle distance Dfw. When the front side vehicle C2 having the inter-vehicle distance d2 exists, the front side vehicle C2 is not determined as the predicted interruption vehicle because the inter-vehicle distance d2> the threshold value Dth1. Therefore, the target acceleration for interruption is not calculated for the front side vehicles C1 and C2, and the deceleration control is not performed.

  When the front side vehicle C3 having the inter-vehicle distance d3 exists, the inter-vehicle distance d3 ≦ the threshold value Dth1 and the inter-vehicle distance d3 ≦ the first set inter-vehicle distance Dfw are determined, so that the front side vehicle C3 is determined as the predicted interrupt vehicle. Therefore, for the front side vehicle C3, the target acceleration for interruption is calculated, and deceleration control can be performed.

  For example, even when the first set inter-vehicle distance Dfw is set to be shorter than the threshold value Dth1, the front side vehicle far from the tracking target vehicle Cb is not determined as the predicted interruption vehicle.

  Thus, according to the present embodiment, the deceleration control is performed on the front side vehicle that is relatively close to the own vehicle and has a great influence on the own vehicle, and the front side vehicle that is relatively far from the own vehicle. Does not perform deceleration control. Thereby, after performing deceleration control with respect to the relatively far front side vehicle, it is possible to suppress unnecessary acceleration / deceleration in which the front side vehicle moves away and accelerates again to approach the tracking target vehicle. Therefore, the driver's uncomfortable feeling can be suppressed.

(Second Embodiment)
In the second embodiment, the predicted interrupt vehicle is determined using the linear distance between the host vehicle and the front side vehicle. Below, it demonstrates centering around difference with 1st Embodiment.

  FIG. 5 is a diagram for explaining the operation of the vehicle travel control apparatus 100 according to the second embodiment. As shown in FIG. 5, it is assumed that one of the front side vehicles C1 and C2 is traveling in an adjacent lane. The linear distance between the center of the front end of the host vehicle Ca and the rear end of the front side vehicle C1 is ds1, and the linear distance between the center of the front end of the host vehicle Ca and the rear end of the front side vehicle C2 is ds2. . When the azimuth angle of the front side vehicle C1 is θ1, the azimuth angle of the front side vehicle C2 is θ2, ds1 = d1 / sin θ1 and ds2 = d2 / sin θ2.

  When the inter-vehicle distance between the host vehicle and the front side vehicle is equal to or less than the first set inter-vehicle distance Dfw and the linear distance between the host vehicle and the front side vehicle is equal to or less than a predetermined threshold Dth2, The front side vehicle is determined as the predicted interruption vehicle.

  This embodiment is preferably applied to the front side radar sensors 11a and 11b having a wider angle range in which a target can be detected. The threshold value Dth2 is set in advance based on the accuracy of the front side radar sensors 11a and 11b. Since the accuracy of the front side radar sensors 11a and 11b decreases as the linear distance between the front side radar sensors 11a and 11b and the target increases, a distance at which acceptable accuracy can be obtained is set as the threshold value Dth2.

  When the front side vehicle C1 having the inter-vehicle distance d1 exists, the front side vehicle C1 is not determined as the predicted interruption vehicle because the linear distance ds1> the threshold value Dth2. When the front side vehicle C2 having the inter-vehicle distance d2 exists, the front side vehicle C2 is determined as the predicted interruption vehicle because the inter-vehicle distance d2 ≦ the first set inter-vehicle distance Dfw and the linear distance ds2 ≦ the threshold value Dth2.

  As described above, according to the present embodiment, the front side vehicle away from the host vehicle at a position where the detection accuracy of the front side radar sensors 11a and 11b is low can be excluded from the deceleration control targets. Therefore, unnecessary acceleration / deceleration can be suppressed.

  Note that the second embodiment and the first embodiment may be combined. That is, the determination condition of the first embodiment is used for the front side vehicle detected by the front radar sensor 10, and the second condition is used for the front side vehicle detected only by the front side radar sensors 11 a and 11 b. The prediction interruption vehicle may be determined using the determination condition of the embodiment.

  The present invention has been described based on the embodiments. The embodiments are exemplifications, and it will be understood by those skilled in the art that various modifications can be made to combinations of the respective constituent elements and processing processes, and such modifications are within the scope of the present invention. .

For example, when it is not necessary to improve the accuracy of control when traveling on a curve having a relatively small radius of curvature, the host vehicle course estimation unit 50 and the correction unit 61 may not be provided.
Further, when it is not necessary to use the interrupt probability, the interrupt probability calculation unit 64 and the interrupt determination result calculation unit 65 may not be provided. Thereby, the process of the inter-vehicle control ECU 20 can be simplified.

DESCRIPTION OF SYMBOLS 10 ... Front radar sensor (detection part), 11a, 11b ... Front side radar sensor (detection part), 30 ... 1st target acceleration calculating part, 63 ... Interruption vehicle determination part, 70 ... Acceleration mediation part, 71 ... 2nd target Acceleration calculator, 72... Target acceleration mediator, 82... Travel controller, 100.

Claims (1)

A detection unit for detecting a tracking target vehicle that travels in front of the host vehicle and a front side vehicle that travels in front of the host vehicle;
The inter-vehicle distance between the host vehicle and the front side vehicle is equal to or less than a predetermined first set inter-vehicle distance, and the inter-vehicle distance or the linear distance between the host vehicle and the front side vehicle is based on the accuracy of the detection unit. When the vehicle is less than or equal to the threshold set in the above, an interrupting vehicle determination unit that determines the front side vehicle as an expected interruption vehicle that is expected to interrupt between the own vehicle and the tracking target vehicle;
A first target acceleration calculation unit that calculates a target acceleration for tracking so that an inter-vehicle distance between the host vehicle and the tracking target vehicle is the first set inter-vehicle distance;
A second target acceleration calculation unit that calculates a target acceleration for interruption so that an inter-vehicle distance between the host vehicle and the predicted interruption vehicle becomes a predetermined second set inter-vehicle distance;
A target acceleration mediation unit that selects a smaller one of the target acceleration for tracking and the target acceleration for interrupt as a target acceleration after mediation; and
A travel control unit that controls the driving force and braking force of the host vehicle so that the acceleration of the host vehicle approaches the target acceleration after the arbitration;
A vehicle travel control device comprising:

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