JP5729912B2 - Follow-up control device - Google Patents

Description

  The present invention relates to a follow-up travel control device that controls the following of a host vehicle to follow a preceding vehicle so as to maintain a set target inter-vehicle distance, and more specifically to setting a target inter-vehicle distance.

  Conventionally, as this type of follow-up running control device, there are one based on the own vehicle speed that sets the target inter-vehicle distance of the follow-up running control based on the vehicle speed of the own vehicle, and one based on the preceding vehicle set based on the vehicle speed of the preceding vehicle. And have been proposed.

  The conventional follow-up travel control device based on the own vehicle speed detects the target inter-vehicle distance of the follow-up running control from a vehicle speed sensor of the own vehicle based on the target inter-vehicle distance on the own vehicle speed side corresponding to the own vehicle speed. It is set to the target inter-vehicle distance on the own vehicle speed side according to the own vehicle speed (see, for example, Patent Document 1 (paragraphs [0002], [0012], [0021], FIG. 1 etc.)).

  The conventional following travel control device based on the preceding vehicle is configured to determine the target inter-vehicle distance for the following traveling control based on the target inter-vehicle distance on the vehicle speed side of the preceding vehicle set in advance corresponding to the vehicle speed of the preceding vehicle. And the target inter-vehicle distance on the vehicle speed side of the corresponding preceding vehicle (see, for example, Patent Document 2 (paragraphs [0005] and [0006], FIG. 6))).

JP 2001-239855 A JP 2005-119522 A

  In the following traveling control device based on the own vehicle speed described in Patent Document 1, the target inter-vehicle distance of the following traveling control changes according to the own vehicle speed from moment to moment. For example, the preceding vehicle has a high constant vehicle speed (for example, 80 km). / H), and the target vehicle distance for the follow-up running control is sufficiently long and the actual inter-vehicle distance is slightly interrupted (even if it fluctuates), there is no problem. When catching up with the preceding vehicle and following the vehicle, the target inter-vehicle distance of the vehicle-speed-based follow-up control changes according to the change in the vehicle speed even though the preceding vehicle is traveling at a constant vehicle speed. There is a possibility that the driving behavior of the host vehicle may become unstable due to the situation where the host vehicle decelerates and the target vehicle distance decreases and the host vehicle accelerates alternately. is there.

  In the case of the preceding vehicle-based following travel control device described in Patent Document 2, when the preceding vehicle travels at a constant high vehicle speed (for example, 80 km / h) with a long target inter-vehicle distance, and the own vehicle follows the preceding vehicle, The target inter-vehicle distance does not change according to changes in the vehicle speed of the host vehicle, and the host vehicle catches up and follows the preceding vehicle with a stable driving behavior. However, if the preceding vehicle decelerates and changes to a low speed or stopped state while the host vehicle and the preceding vehicle are following, the target inter-vehicle distance based on the preceding vehicle may become abnormally short.

FIG. 8 schematically shows the following traveling based on the preceding vehicle. FIG. 8A shows the case where the preceding vehicle a is traveling at a high speed, for example, 80 km / h. The target inter-vehicle distance α is a sufficiently long distance of 40 m, for example, based on the preceding vehicle. (B) is a case where the preceding vehicle a decelerates and stops (0 km / h), and the target inter-vehicle distance α of the own vehicle b is shortened to approximately 0 m on the preceding vehicle base.

  In such follow-up running control with a short target inter-vehicle distance α, the host vehicle b can easily interrupt the target inter-vehicle distance α.

  It is an object of the present invention to provide a follow-up running control device that has good follow-up performance in follow-up running control when the running behavior of the host vehicle does not become unstable and the preceding vehicle changes to a deceleration or stop state. Objective.

To achieve the above object, following distance control device of the present invention, there is provided a follow-up running control device for following distance control to the preceding vehicle to the host vehicle so as to keep the target inter-vehicle distance is set the follow-up run, self A vehicle speed sensor for detecting the vehicle speed, an inter-vehicle distance detecting means for detecting the inter-vehicle distance between the host vehicle and the preceding vehicle, and a relative speed of the preceding vehicle obtained from a time change of the inter-vehicle distance detected by the inter-vehicle distance detecting means. The target vehicle distance corresponding to the current preceding vehicle speed is obtained from a data map in which target vehicle distances for each of a plurality of different preceding vehicle speeds are determined in advance by adding the host vehicle speed by the vehicle speed sensor to obtain a current preceding vehicle speed. a first calculating means for calculating a target inter-vehicle distance of the preceding vehicle speed side, the data map in which the target inter-vehicle distance is set for each advance a plurality of different vehicle speed, the vehicle speed Se A second computing means for obtaining a target inter-vehicle distance corresponding to the current vehicle speed by Sa as the target inter-vehicle distance subject vehicle speed side, the following cruise control target inter-vehicle distance of the preceding vehicle speed side obtained by said first arithmetic means The target inter-vehicle distance on the preceding vehicle speed side that is selected by the first calculation means when the target inter-vehicle distance is preferentially selected and the target inter-vehicle distance on the preceding vehicle speed side becomes shorter than the set switching permission distance. And the target inter-vehicle distance on the own vehicle speed side determined by the second calculation means , whichever is longer, is selected as the target inter-vehicle distance for the following travel control, and the target inter-vehicle distance on the preceding vehicle speed side is set. allow the distance except when shortened below; and a target inter-vehicle distance selecting means for maintaining the target inter-vehicle distance preferentially selected the preceding vehicle speed side to the target inter-vehicle distance follow-up running control Are (claim 1).

For follow-up running control device of the present invention according to claim 1, the first calculating means obtains a target inter-vehicle distance of the preceding vehicle speed side in the preceding vehicle speed based second computing means of vehicle speed side vehicle speed based Ru obtains a target vehicle-to-vehicle distance. If the target inter-vehicle distance on the preceding vehicle speed side is longer than the predetermined switching permission distance by the target inter-vehicle distance selecting means, the target inter-vehicle distance on the preceding vehicle speed side obtained by the first calculating means is set as the target inter-vehicle distance for follow-up travel control. The following traveling control is performed with stable traveling behavior so that the target inter-vehicle distance of the following traveling control does not change depending on the change in the vehicle speed of the own vehicle. Further, when the target inter-vehicle distance on the preceding vehicle speed side becomes shorter than the predetermined switching permission distance due to deceleration or stop of the preceding vehicle, the target inter-vehicle distance on the own vehicle speed side obtained by the second calculating means is set as the target inter-vehicle distance for the following traveling control. Select and perform follow-up running control. At this time, the target inter-vehicle distance of the follow-up travel control becomes longer than when the target inter-vehicle distance on the preceding vehicle speed side is selected, and the follow-up performance is improved.

  Therefore, it is possible to provide a follow-up travel control device that does not cause the travel behavior of the host vehicle to be unstable and that has good follow-up performance in follow-up travel control when the preceding vehicle changes to a deceleration or stop state.

It is a block diagram of the following run control device of one embodiment of the present invention. It is explanatory drawing of an example of the change of the target inter-vehicle distance of FIG. It is explanatory drawing of an example of selection of the target inter-vehicle distance of FIG. It is explanatory drawing of the other example of selection of the target inter-vehicle distance of FIG. It is explanatory drawing of the other example of selection of the target inter-vehicle distance of FIG. It is explanatory drawing of the other example of selection of the target inter-vehicle distance of FIG. It is a flowchart which shows the setting procedure of the target inter-vehicle distance of FIG. It is explanatory drawing of the target inter-vehicle distance set by the preceding vehicle base, (a) shows the target inter-vehicle distance at the time of high speed driving | running | working of a preceding vehicle, (b) shows the target inter-vehicle distance when a preceding vehicle stops.

  Next, in order to describe the present invention in more detail, an embodiment will be described in detail with reference to FIGS.

  FIG. 1 shows a follow-up travel control device of this embodiment mounted on a host vehicle 1, in FIG. 1, 2 is a control switch for operating and setting control mode switching and the like, 3 is a wiper switch linked to a wiper operation, 4 Is a camera as an image sensor, which is composed of a monochrome or color CCD monocular camera, a stereo camera, or the like, and is provided so as to photograph the front of the host vehicle in the passenger compartment.

  Reference numeral 5 denotes a ranging radar provided in the front bumper portion of the vehicle 1, which is composed of various scanning radars such as a laser radar and a millimeter wave radar and scans in front of the own vehicle in the left-right direction (horizontal width direction). To do. Reference numeral 6 denotes a vehicle speed sensor (wheel speed sensor) of the host vehicle 1, which detects the host vehicle speed every moment. 7 and 8 are a steering angle sensor and a yaw rate sensor, which detect the steering angle and yaw rate of the vehicle behavior.

  9 is a follow-up running control unit having an ECU configuration composed of a microcomputer or the like, which executes a preset follow-up running control program, outputs an acceleration / deceleration command, braking command, etc. for follow-up running control, which will be described later. Control display / alarm such as warning and avoidance.

  Reference numerals 10, 11, and 12 denote a display alarm unit, a throttle control unit, and a brake control unit that operate according to a command from the follow-up travel control unit 9, and the display alarm unit 10 is provided at an appropriate position of the display instrument panel, for example. The throttle control unit 11 controls the throttle opening of the vehicle 1 according to the acceleration / deceleration command for the follow-up running control, and the brake control unit 12 uses the braking command for the follow-up running control. Therefore, the brake mechanism of the vehicle 1 is controlled.

  The follow-up running control unit 9 operates as outlined below, similar to the well-known follow-up running control, by executing a follow-up running control program.

  On the condition that the follow-up running mode is selected by the control switch 2, the follow-up running control unit 8 executes the follow-up running control program, and determines the distance between the own vehicle 1 and the preceding vehicle based on the search result of the radar 5. Information, or information on the inter-vehicle distance between the vehicle 1 and the preceding vehicle obtained by specifying the preceding vehicle by a known sensor fusion process based on the captured image of the camera 4 and the information on the search result of the radar 5, and the vehicle speed The information of the vehicle speed (own vehicle speed) of the own vehicle 1 obtained from the sensor 6 and the information on the behavior of the own vehicle 1 of the steering angle sensor 7 and the yaw rate sensor 8 are repeatedly collected.

  Further, based on the information of the inter-vehicle distance and the information of the own vehicle speed every moment, the target inter-vehicle distance of the follow-up running control is set every moment as described later, and the target inter-vehicle distance of the follow-up running control set by the inter-vehicle distance is set. Thus, the acceleration / deceleration command and the braking command are given to the control units 11 and 12 to control the traveling of the vehicle 1.

  In order to set the target inter-vehicle distance for the follow-up running control, the follow-up running control unit 9 includes first calculation means, second calculation means, and target inter-vehicle distance selection means of the present invention formed by software processing.

  The first calculating means is a means for calculating the target inter-vehicle distance on the preceding vehicle base speed side based on the preceding vehicle based on the vehicle speed and the inter-vehicle distance of the preceding vehicle, and the second calculating means is based on the own vehicle speed and the inter-vehicle distance. This is means for calculating a target inter-vehicle distance on the vehicle speed side based on the vehicle speed.

  When the target inter-vehicle distance selection means preferentially selects the target inter-vehicle distance on the preceding vehicle speed side as the target inter-vehicle distance of the following traveling control, and the target inter-vehicle distance on the preceding vehicle speed side becomes shorter than the set switching allowable distance Further, the longer one of the target inter-vehicle distance on the preceding vehicle speed side and the target inter-vehicle distance on the own vehicle speed side is selected as the target inter-vehicle distance for the follow-up travel control.

  Next, the inter-vehicle distance detected by the host vehicle 1 and the preceding vehicle is La, the vehicle speed of the preceding vehicle is Vp, the host vehicle speed is Vn, the target inter-vehicle distance on the preceding vehicle speed side of the preceding vehicle base is Lp, and the host vehicle speed is based on the host vehicle speed. The processing of the first and second calculation means and the target inter-vehicle distance selection means will be described, assuming that the target inter-vehicle distance is Ln, the switching permission distance is Lsw, and the target inter-vehicle distance for follow-up travel control is Lr.

  The first calculating means obtains the relative speed of the preceding vehicle from the time change of the inter-vehicle distance La between the own vehicle 1 and the preceding vehicle, adds the own vehicle speed Vn of the vehicle speed sensor 6 to this relative speed, and the vehicle speed of the preceding vehicle from moment to moment. Vp is obtained, and the target inter-vehicle distance Lp for the combination of the vehicle speed Vp and the inter-vehicle distance La is calculated from a data map in which the target inter-vehicle distance Lp for the combination of a plurality of vehicle speeds Vp and the inter-vehicle distance La is set. Calculated by

  Based on the own vehicle speed Vn of the vehicle speed sensor 6 and the inter-vehicle distance La between the own vehicle 1 and the preceding vehicle, the second calculation means calculates a target inter-vehicle distance Ln for a combination of the vehicle speed Vn and the inter-vehicle distance La, for example, a plurality of It is calculated by a well-known complementary calculation from a data map in which the target inter-vehicle distance Ln for the combination of the vehicle speed Vn and the inter-vehicle distance La is set.

  When the preceding vehicle is traveling at a constant speed, the target inter-vehicle distance Lp based on the preceding vehicle is constant and does not change. Therefore, if the target inter-vehicle distance Lp is set to the target inter-vehicle distance Lr of the follow-up travel control, the own vehicle 1 travels stably without fluctuation of the target inter-vehicle distance Lr. On the other hand, the actual inter-vehicle distance La changes in length according to the magnitude relationship between the vehicle speeds Vp and Vn, and the own vehicle speed Vn is larger than the preceding vehicle speed until the own vehicle 1 catches up behind the target inter-vehicle distance Lr of the preceding vehicle. The target inter-vehicle distance Ln is larger than the target inter-vehicle distance Lp. Further, when the own vehicle 1 catches up behind the target inter-vehicle distance Lr of the preceding vehicle, the own vehicle 1 changes from acceleration to deceleration in order to keep the inter-vehicle distance La constant. As a result, the inter-vehicle distance La becomes the target inter-vehicle distance Lr. As the vehicle 1 becomes longer, the vehicle 1 changes from deceleration to acceleration. As a result of this repetition, even if the preceding vehicle is traveling at a constant speed, the target inter-vehicle distance Ln varies. Therefore, if the target inter-vehicle distance Ln is set to the target inter-vehicle distance Lr, the traveling behavior of the host vehicle 1 becomes unstable. .

  Next, for example, when a preceding vehicle traveling at a constant speed of Vp = 80 km / h decelerates and stops, the target inter-vehicle distance Lp based on the preceding vehicle becomes smaller (shorter) as the vehicle speed Vp of the preceding vehicle decreases. When the preceding vehicle stops (Vp = 0 km / h), the target inter-vehicle distance Lp is several meters close to 0 m even though the following vehicle 1 is traveling at a certain vehicle speed Vn. If the target inter-vehicle distance Lp is set to the target inter-vehicle distance Lr, the inter-vehicle distance La is not allowed to interrupt the target inter-vehicle distance Lr, and the follow-up performance of the follow-up traveling control is reduced. On the other hand, the target inter-vehicle distance Ln based on the own vehicle speed decreases as the inter-vehicle distance La decreases as the preceding vehicle decelerates. However, the vehicle speed (own vehicle speed Vn) of the own vehicle 1 that travels following the preceding vehicle is the vehicle speed of the preceding vehicle. Even if the vehicle changes later than Vp and the preceding vehicle stops, the target inter-vehicle distance Ln becomes an appropriate distance in accordance with the actual host vehicle speed Vn. Therefore, when the target inter-vehicle distance Ln is set to the target inter-vehicle distance Lr, the follow-up performance of the follow-up traveling control can be ensured without any problem even if the inter-vehicle distance La slightly interrupts the target inter-vehicle distance Lr.

  FIG. 2 shows a change example of the target inter-vehicle distances Lp and Ln when the preceding vehicle decelerates from the state where the preceding vehicle is traveling at a high speed and constant speed as described above. The solid line p is the target inter-vehicle distance Lp and the solid line n is the target inter-vehicle distance. Ln. Moreover, the broken line sw in the figure is the switching permission distance Lsw.

  As is clear from the above description and FIG. 2, when the preceding vehicle travels at a high speed and the inter-vehicle distance Lp based on the preceding vehicle is large and the vehicle can appropriately travel with the follow-up traveling control of the target inter-vehicle distance Lp, The following traveling control of the distance Lp is more stable and advantageous than the following traveling control of the target inter-vehicle distance Ln based on the own vehicle speed. On the other hand, when the preceding vehicle decelerates and runs at low speed or stops, the target inter-vehicle distance Ln becomes larger than the target inter-vehicle distance Lp. This is more appropriate than the following traveling control of the target inter-vehicle distance Lp.

  Therefore, in consideration of an error in the inter-vehicle distance La due to the follow-up traveling, the lower limit target inter-vehicle distance Lp at which the follow-up travel control of the target inter-vehicle distance Lp based on the preceding vehicle can be appropriately performed is set as the switching permission distance Lsw. The switching permission distance Lsw is set to a distance corresponding to the target inter-vehicle distance Lp when the vehicle speed Vp of the preceding vehicle is 20 km / h, and more specifically, from preset distance candidates of approximately 13 m, 15 m, and 16 m. The distance selected and set by the driver using a button operation or the like.

  Then, the target inter-vehicle distance selecting means (1) preferentially selects the target inter-vehicle distance Lp based on the preceding vehicle and sets it as the target inter-vehicle distance Lr for the follow-up travel control, and (2) the target inter-vehicle distance Lp based on the preceding vehicle. Selects the longer one of the target vehicle distance Lp based on the preceding vehicle and the target vehicle distance Ln based on the own vehicle speed (the longer distance is appropriate) and follows when the vehicle becomes shorter than the set switching permission distance Lsw. It is set to the target inter-vehicle distance Lr for travel control.

  In this way, the target inter-vehicle distance Lr for the follow-up travel control is preferentially set when the preceding vehicle is traveling at a high constant speed and the target inter-vehicle distance Lp based on the preceding vehicle is sufficiently long. The target inter-vehicle distance Lp is set so that the target inter-vehicle distance Lr of the follow-up running control is not changed depending on the own vehicle speed Vn, and the follow-up running control is performed with a stable running behavior. When the preceding vehicle-based target inter-vehicle distance Lp becomes shorter than the switching permission distance Lsw due to the deceleration or stop of the preceding vehicle, the target inter-vehicle distance Ln based on the own vehicle speed is selected as the target inter-vehicle distance Lr for the following traveling control. Is done. At this time, the target inter-vehicle distance Lr for the follow-up running control becomes longer than when the target inter-vehicle distance Lp based on the preceding vehicle is selected, and the follow-up performance is improved.

  FIG. 3 shows an example of the above selection change of the target inter-vehicle distance Lr of the follow-up running control accompanying deceleration or stop of the preceding vehicle. The solid line p in the figure indicates the target inter-vehicle distance Lp based on the preceding vehicle, and the broken line n indicates the own vehicle speed-based. The target inter-vehicle distance Ln and the broken line sw indicate the switching permission distance Lsw, and the solid line r is the target inter-vehicle distance Lr for the follow-up travel control. In this example, the target inter-vehicle distance Lp based on the preceding vehicle is shortened to the switching permission distance Lsw at time t1, and the target inter-vehicle distance Lr in the follow-up travel control is changed from the target inter-vehicle distance Lp based on the preceding vehicle based on the own vehicle speed. When the target inter-vehicle distance Ln based on the own vehicle speed becomes shorter than the target inter-vehicle distance Lp based on the preceding vehicle at time t2, the target inter-vehicle distance Lr for the follow-up travel control precedes the target inter-vehicle distance Ln based on the own vehicle speed. The vehicle-based target inter-vehicle distance Lp is switched.

  Accordingly, the target inter-vehicle distance Lr for the follow-up travel control is always set to the longer of the preceding vehicle-based target inter-vehicle distance Lp and the own vehicle speed-based target inter-vehicle distance Ln, and the traveling behavior of the own vehicle 1 may become unstable. In addition, it is possible to provide a follow-up travel control device with good follow-up performance of follow-up travel control when the preceding vehicle changes to a deceleration or stop state.

  By the way, in the present embodiment, the target inter-vehicle distance Lp based on the preceding vehicle is further shortened to the switching permission distance Lsw, and the target inter-vehicle distance selecting means determines the target based on the own vehicle speed from the selection of the target inter-vehicle distance Lp based on the preceding vehicle. When switching to the selection of the inter-vehicle distance Ln, the target inter-vehicle distance Lr of the follow-up travel control is maintained at the switching allowable distance Lsw until the target inter-vehicle distance Ln based on the host vehicle speed becomes short to the switching allowable distance Lsw.

  FIG. 4 shows an example of the above selection change of the target inter-vehicle distance Lr of the follow-up travel control when maintained as described above. In FIG. 4, the solid line p is the target inter-vehicle distance Lp based on the preceding vehicle, and the broken line n is the base vehicle speed-based. The target inter-vehicle distance Ln and the broken line sw indicate the switching permission distance Lsw, and the solid line r is the target inter-vehicle distance Lr for the follow-up travel control. In the case of this example, when the target inter-vehicle distance Lp based on the preceding vehicle is shortened to the switch permission distance Lsw at time t11, the follow-up travel control is performed until time t12 when the target inter-vehicle distance Ln based on the host vehicle speed is shortened to the switch permission distance Lsw. The target inter-vehicle distance Lr is maintained at the switching permission distance Lsw, the target inter-vehicle distance Lr of the follow-up travel control is switched from the time t12 to the target inter-vehicle distance Ln based on the own vehicle speed, and then the target inter-vehicle distance Ln based on the own vehicle speed is obtained at the time t13. When the target vehicle distance Lp based on the preceding vehicle becomes shorter, the target vehicle distance Lr of the follow-up travel control is switched from the target vehicle distance Ln based on the own vehicle speed to the target vehicle distance Lp based on the preceding vehicle.

  In FIG. 5, as described above, the target inter-vehicle distance Lp based on the preceding vehicle is shortened to the switch permission distance Lsw at time t11, but before the target inter-vehicle distance Ln based on the own vehicle speed is shortened to the switch permission distance Lsw, An example of selective change of the target inter-vehicle distance Lr for follow-up travel control when the preceding vehicle is accelerated and restarted is shown. In this case, the preceding vehicle is accelerated at time t13 and the target inter-vehicle distance Lp based on the preceding vehicle is increased. Therefore, the target inter-vehicle distance Lp based on the preceding vehicle increases to the switching permission distance Lsw at time t14 before the target inter-vehicle distance Ln based on the host vehicle speed becomes shorter than the switching permission distance Lsw. From time t11 to time t14, the switching permission distance Lsw is maintained, and then the target vehicle-to-vehicle distance Lp based on the preceding vehicle is switched.

  In this way, when switching from the selection of the target inter-vehicle distance Lp based on the preceding vehicle to the selection of the target inter-vehicle distance Ln based on the own vehicle speed, until the target inter-vehicle distance Ln based on the own vehicle speed becomes shorter than the switching permission distance Lsw, The target inter-vehicle distance Lr for the following travel control is maintained at the switching permission distance Lsw and does not increase suddenly. The target inter-vehicle distance Lr for the follow-up travel control is changed from the target inter-vehicle distance Lp based on the preceding vehicle to the target inter-vehicle speed based target vehicle distance Lp. It is possible to smoothly switch to the distance Ln, the control stability is improved, and the followability is further improved.

  By the way, when the preceding vehicle changes from decelerating or stopping to acceleration traveling, the target inter-vehicle distance selection means switches from selecting the target inter-vehicle distance Ln based on the own vehicle speed to selecting the target inter-vehicle distance Lp based on the preceding vehicle. When the own vehicle speed-based target inter-vehicle distance Ln is first increased to the switch-permitted distance Lsw, the target inter-vehicle distance Lr of the following travel control is switched until the target vehicle-based distance Lp based on the preceding vehicle is increased to the switch-permitted distance Lsw. It is more preferable to maintain the permitted distance Lsw in terms of control stability and the like.

  FIG. 6 shows an example of a change in the target inter-vehicle distance Lr of the follow-up running control when the preceding vehicle decelerates or stops and then accelerates again. In this example as well, the solid line p in the figure indicates the target inter-vehicle distance based on the preceding vehicle. Lp, the broken line n represents the target vehicle distance Ln based on the host vehicle speed, the broken line sw represents the switching permission distance Lsw, and the solid line r represents the target inter-vehicle distance Lr for the tracking travel control.

  Then, when the target inter-vehicle distance Lp based on the preceding vehicle is reduced to the switching allowance distance Lsw at the time t21, the target inter-vehicle distance of the follow-up travel control is until the time t22 when the target inter-vehicle distance Ln based on the own vehicle speed is shortened to the switching allowance distance Lsw. Lr is maintained at the switching permission distance Lsw, the target inter-vehicle distance Lr of the follow-up running control is switched from the time t22 to the target inter-vehicle distance Ln based on the own vehicle speed, and then the target inter-vehicle distance Ln based on the own vehicle speed is set to the preceding vehicle base at the time t23. When the target inter-vehicle distance Lp becomes shorter than the target inter-vehicle distance Lp, the target inter-vehicle distance Lr of the follow-up travel control is switched from the target inter-vehicle distance Ln based on the own vehicle speed to the target inter-vehicle distance Lp based on the preceding vehicle.

  Furthermore, the preceding vehicle-based target inter-vehicle distance Lp becomes longer, for example, when the preceding vehicle starts to travel again, and as the own vehicle 1 follows, the target inter-vehicle distance Ln based on the own vehicle speed is also delayed, resulting in a steeper change. become longer.

  When the target inter-vehicle distance Lp based on the preceding vehicle is shorter than the switch-permitted distance Lsw and the target inter-vehicle distance Ln based on the host vehicle speed becomes longer than the target inter-vehicle distance Lp based on the preceding vehicle at time t24, The distance Lr is switched to the target vehicle distance Ln based on the own vehicle speed.

  Furthermore, when the target vehicle distance Ln based on the host vehicle speed becomes longer at the switching permission distance Lsw at time t25, the target inter-vehicle distance Lr of the follow-up travel control is increased until the target vehicle distance Lp based on the preceding vehicle becomes longer than the switching permission distance Lsw. Is maintained at the switching permission distance Lsw, and then the target inter-vehicle distance Lp based on the preceding vehicle is increased to the switching permission distance Lsw at time t26, so that the target inter-vehicle distance Lr of the follow-up travel control becomes the target inter-vehicle distance Lp based on the preceding vehicle. Switch smoothly without sudden fluctuations.

  Therefore, even when the preceding vehicle travels again, it is possible to realize the follow-up running control that is stable and has good follow-up performance.

  Specifically, the above-described switching of the target inter-vehicle distance Lr for the follow-up traveling control is as follows: (1) If Lp ≦ Lsw and Ln ≧ Lp are satisfied, Lr = Lsw when Ln ≧ Lsw, otherwise If Lr = Ln and (2) Lp ≦ Lsw and Ln ≧ Lp are not satisfied, Lr = Lp can be realized.

  FIG. 7 shows an example of the procedure for setting the target inter-vehicle distance Lr for the follow-up running control by the first computing means, the second computing means, and the target inter-vehicle distance selecting means of the follow-up running control unit 9. First, the first computing means uses the preceding vehicle base. The vehicle distance Lp is calculated (step S1), the vehicle speed based vehicle distance Ln is calculated by the second calculation means (step S2), and the selected switching permission distance Lsw is set (step S3).

  Next, it is determined whether or not the conditions of Lp ≦ Lsw and Ln ≧ Lp are satisfied (step S4). If not satisfied (NO), the process proceeds to step S5, and the target inter-vehicle distance Lr of the follow-up traveling control is determined. Is set as the target inter-vehicle distance Lp based on the preceding vehicle.

  On the other hand, in step S4, if the condition of Lp ≦ Lsw and Ln ≧ Lp is satisfied (YES), the process proceeds to step S6 to determine whether or not Ln ≧ Lsw is satisfied, and if satisfied (YES). Then, the process proceeds to step S7, the target inter-vehicle distance Lr of the follow-up running control is maintained at the switching permission distance Lsw, and if not established (NO), the process proceeds from step S6 to step S8 and the target inter-vehicle distance Lr of the follow-up running control is set. The target inter-vehicle distance Ln is set based on the own vehicle speed.

  Therefore, in the case of the above embodiment, basically, the longer one of the preceding vehicle-based inter-vehicle distance Lp and the own vehicle speed-based inter-vehicle distance Ln can be set by switching to the target inter-vehicle distance Lr of the follow-up travel control. It is possible to provide a follow-up running control device with good follow-up performance of follow-up running control in a low speed range when the running behavior of the vehicle 1 does not become unstable and the preceding vehicle changes to a deceleration or stop state. .

  Further, when the target inter-vehicle distance Lr is switched in the follow-up travel control, the switching allowable distance Lsw is maintained to prevent sudden fluctuation, and the target inter-vehicle distance Ln can be smoothly switched from the target inter-vehicle distance Lp and the control can be stably performed. Improves the follow-up performance.

  The present invention is not limited to the above-described embodiment, and various modifications other than those described above can be made without departing from the spirit thereof. For example, the switching permission distance Lsw and the like are appropriately set. May be set.

  Further, the configuration, processing procedure, etc. of the first calculation means, the second calculation means, the target inter-vehicle distance selection means, etc. of the follow-up travel control unit 9 may be any.

  The present invention can be applied to various vehicle follow-up control devices.

1 Own vehicle 9 Follow-up traveling control unit Ln Target vehicle-to-vehicle distance based on own-vehicle speed Lp Target vehicle-to-vehicle distance based on preceding vehicle Lsw Switching permission distance Lr Target-to-vehicle distance for follow-up running control

Claims (1)

It is a follow-up running control device that controls running following a preceding vehicle so as to maintain a set target inter-vehicle distance for following running,
A vehicle speed sensor for detecting the vehicle speed;
Inter-vehicle distance detection means for detecting the inter-vehicle distance between the host vehicle and the preceding vehicle;
The vehicle speed sensor adds the own vehicle speed to the relative speed of the preceding vehicle obtained from the time variation of the inter-vehicle distance detected by the inter-vehicle distance detecting means to obtain the current preceding vehicle speed, and each of a plurality of different preceding vehicle vehicle speeds in advance. First calculation means for obtaining a target inter-vehicle distance corresponding to the current preceding vehicle speed as a target inter-vehicle distance on the preceding vehicle speed side from a data map in which a target inter-vehicle distance is set;
Second calculation means for obtaining a target inter-vehicle distance corresponding to the current own vehicle speed by the vehicle speed sensor as a target inter-vehicle distance on the own vehicle speed side from a data map in which target inter-vehicle distances for a plurality of different own vehicle speeds are set in advance;
The target inter-vehicle distance on the preceding vehicle speed side obtained by the first calculating means is preferentially selected as the target inter-vehicle distance for follow-up travel control, and the target inter-vehicle distance on the preceding vehicle speed side is set to be equal to or less than the set switching permission distance. When the vehicle speed becomes shorter, the following traveling control is performed by using the longer one of the target inter-vehicle distance on the preceding vehicle speed side obtained by the first computing means and the target inter-vehicle distance on the own vehicle speed side obtained by the second computing means. The target inter-vehicle distance on the preceding vehicle speed side is preferentially selected, except when the target inter-vehicle distance on the preceding vehicle speed side becomes shorter than the set switching allowable distance. And a target inter-vehicle distance selection means for maintaining the target inter-vehicle distance.

Images