JP2014065466A - Travel support device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suitably support a lane change of a driver's own vehicle.SOLUTION: A travel support device (100) for supporting a lane change of a driver's own vehicle (C1) includes prediction means (120) for predicting whether or not a situation of an increase in a vehicle speed (V2) of a front vehicle (C2) is brought about, on the basis of a road condition of a traffic lane (L1) where the front vehicle (C2) travels, and support means (140) for supporting traveling of the driver's own vehicle so that the driver's own vehicle cannot perform the lane change, when it is predicted that the situation of the increase in the vehicle speed of the front vehicle is brought about.

Description

  The present invention relates to a technical field of a driving support device that supports driving of a vehicle, for example.

  In recent years, development of a driving support device that supports safe or comfortable driving of a vehicle has been promoted. For example, in Patent Document 1, a desired operation of the host vehicle (acceleration / deceleration movement in the vehicle traveling direction, lane change movement to the left and right lanes, etc.) based on a prediction formula describing a predicted future behavior of the other vehicle is disclosed. A driving support device for determining the vehicle is disclosed.

  In addition, Patent Document 2 and Patent Document 3 are given as prior art related to the present invention.

JP 2003-228800 A Japanese Patent Laid-Open No. 2004-258889 JP-A-10-250508

  By the way, when the host vehicle overtakes the vehicle ahead of the host vehicle, the host vehicle changes the lane from the currently traveling lane to the target lane and passes the target vehicle by driving the target lane. In many cases, the lane change is performed so as to return from the target lane to the original travel lane. Therefore, it is preferable that the above-described travel support device also assists in changing the lane of the host vehicle so as to support the travel of the host vehicle.

  However, the vehicle speed of the preceding vehicle at the time when the host vehicle starts overtaking may increase before the overtaking of the preceding vehicle is completed. For example, if the vehicle in front that was traveling on an uphill when the host vehicle started overtaking would be traveling on a downhill while the host vehicle was overtaking, the vehicle speed of the vehicle ahead May increase. Or, for example, when the vehicle ahead traveling on a curved road when the host vehicle starts overtaking is in a situation where the host vehicle travels on a straight road while overtaking, the vehicle ahead The vehicle speed may increase. In such a case, due to an increase in the vehicle speed of the preceding vehicle, the host vehicle may not be able to complete passing the preceding vehicle. For this reason, although the overtaking of the preceding vehicle cannot be completed, there arises a technical problem that the lane change of the own vehicle is supported (that is, the lane change is performed unnecessarily).

  Note that the driving support device disclosed in Patent Document 1 described above is located behind the own vehicle when the own vehicle changes to the target lane in order to pass the preceding vehicle running at a relatively slow vehicle speed. It is merely determined whether or not to change the lane of the own vehicle according to the traveling state of the other vehicle traveling in the target lane (see, for example, paragraph 0072 of Patent Document 1). In other words, the above-described driving support device disclosed in Patent Document 1 merely determines whether or not to change the lane of the host vehicle without considering the driving state of the preceding vehicle located in front of the host vehicle. . Therefore, the technical problem described above can still occur in the travel support device disclosed in Patent Document 1 described above.

  The present invention has been made in view of the above-described problems, for example, and an object of the present invention is to propose a travel support device that can favorably support the lane change of the host vehicle.

<1>
The travel support device of the present invention is a travel support device that supports a lane change of the host vehicle, and the front vehicle is based on a road condition of a travel lane in which a forward vehicle located in front of the host vehicle is traveling. Predicting means for predicting whether or not the vehicle speed of the vehicle will increase, and when the vehicle speed of the preceding vehicle is predicted to increase, the vehicle does not change the lane of the vehicle Support means for supporting the running of the vehicle.

  According to the driving support apparatus of the present invention, it is possible to support a lane change of the host vehicle (for example, a lane change from a currently driving lane to a target lane adjacent to the driving lane). The “lane change” supported by the driving support device of the present invention is typically in front of the host vehicle and traveling in the same driving lane as the driving lane in which the host vehicle is traveling. This is a lane change performed by the host vehicle in order to pass the vehicle. However, the “lane change” supported by the driving support device of the present invention may be a lane change performed by the host vehicle under other circumstances. However, the “lane change” supported by the driving support device of the present invention is a situation in which there is a forward vehicle traveling in the same traveling lane as the traveling lane in front of the own vehicle. It is preferable that the lane change is performed by the host vehicle below.

  In order to support the lane change of the host vehicle, the travel support device includes a prediction unit and a support unit.

  The prediction means predicts whether or not the vehicle speed of the preceding vehicle will increase based on the road condition of the traveling lane in which the preceding vehicle is traveling. In other words, the predicting means predicts in advance whether or not the vehicle speed of the preceding vehicle will increase based on the road condition of the traveling lane in which the preceding vehicle is traveling before the vehicle speed of the preceding vehicle changes. . In particular, it is preferable that the predicting unit predicts whether or not the vehicle speed of the preceding vehicle increases during a period from when the own vehicle starts overtaking the preceding vehicle to completion. In other words, the vehicle speed of the front vehicle increases compared to the vehicle speed of the front vehicle at the time when the host vehicle starts overtaking the front vehicle between the start and completion of the overtaking of the front vehicle. It is preferable to predict whether a situation will occur.

  Here, the “road condition” typically means the condition of the traveling lane itself. Specifically, examples of the “road condition” include, for example, characteristics, properties, characteristics, structures, environments, and the like peculiar to the traveling lane itself. More specifically, examples of the “road condition” include, for example, the gradient of the traveling lane, the shape of the traveling lane, and the like.

  Such road conditions may affect the vehicle speed of the preceding vehicle. For example, when the forward vehicle is traveling on a traveling lane that switches from a flat gradient or an upward gradient to a downward gradient, it is assumed that the vehicle speed of the forward vehicle is likely to increase after the forward vehicle starts traveling on the downward gradient. Alternatively, for example, when the forward vehicle is traveling on a travel lane that switches from a curved road to a straight road, it is assumed that the vehicle speed of the forward vehicle is likely to increase after the forward vehicle starts traveling on the straight road. In this way, the predicting means is the road corresponding to the road state of the traveling lane in which the preceding vehicle is traveling (that is, not only the position where the preceding vehicle is currently traveling, but also the position where the preceding vehicle is predicted to travel in the future). It is possible to predict whether or not the vehicle speed of the vehicle ahead will increase.

  When it is predicted that the vehicle speed of the preceding vehicle will increase by the predicting means, the support means does not change the lane of the own vehicle (for example, lane change accompanying overtaking of the preceding vehicle). Assist driving. In other words, the support means supports the traveling of the host vehicle so that the host vehicle continues to travel in the currently traveling lane when the prediction means predicts that the vehicle speed of the forward vehicle will increase. . On the other hand, when it is predicted that the vehicle speed of the preceding vehicle will not increase by the predicting means, the support means performs lane change of the own vehicle (for example, lane change accompanying overtaking of the preceding vehicle) You may support driving | running | working of the own vehicle.

  Here, if it is predicted that the vehicle speed of the preceding vehicle will increase, even if the own vehicle changes lanes to overtake the preceding vehicle, The vehicle speed may increase. As a result, there is a possibility that even if the host vehicle changes lanes in order to pass the preceding vehicle, the host vehicle cannot complete passing the preceding vehicle. However, in the present invention, even if the host vehicle changes the lane to overtake the preceding vehicle, if the situation in which the host vehicle cannot pass the preceding vehicle may occur, the own vehicle is not changed. Is supported. Therefore, there is little or no need for the host vehicle to make unnecessary lane changes. As described above, the driving support device of the present invention can suitably support the lane change of the host vehicle.

  Note that the predicting means not only predicts whether or not the vehicle speed of the preceding vehicle increases, but also increases the vehicle speed of the preceding vehicle (for example, as described later, a downward gradient or a straight road) It may be predicted whether or not the host vehicle completes overtaking of the preceding vehicle before the vehicle travels. In this case, when it is predicted that the own vehicle will not complete the overtaking of the preceding vehicle before the vehicle speed of the preceding vehicle increases, the support means does not change the lane of the own vehicle. It is preferable not to support the driving of the vehicle. On the other hand, when it is predicted that the host vehicle will complete the overtaking of the preceding vehicle before the vehicle speed of the preceding vehicle increases, the support means does not change the lane of the own vehicle. It is preferable to support driving.

  In this case, the prediction means compares the time required for the vehicle speed of the preceding vehicle to increase and the time required for the host vehicle to complete the overtaking of the preceding vehicle, thereby determining the vehicle speed of the preceding vehicle. It may be predicted whether or not the host vehicle completes overtaking of the preceding vehicle before the situation increases. If the time required for the vehicle speed of the preceding vehicle to increase is greater than the time required for the host vehicle to complete overtaking the preceding vehicle, the predicting means will increase the vehicle speed of the preceding vehicle. It may be predicted that the host vehicle completes overtaking the preceding vehicle. On the other hand, when the time required for the vehicle speed of the preceding vehicle to increase becomes less than or equal to the time required for overtaking the preceding vehicle by the host vehicle, the prediction means increases the vehicle speed of the preceding vehicle. It may be predicted that the overtaking of the preceding vehicle by the host vehicle will not be completed before the situation occurs.

  Alternatively, for example, the predicting means compares the distance traveled by the host vehicle before the vehicle speed of the preceding vehicle increases and the distance traveled by the host vehicle before the host vehicle completes overtaking the preceding vehicle. Thus, it may be predicted whether or not the own vehicle completes overtaking of the preceding vehicle before the vehicle speed of the preceding vehicle increases. When the distance that the host vehicle travels before the vehicle speed of the preceding vehicle increases becomes greater than the distance that the host vehicle travels by the time the host vehicle completes overtaking the preceding vehicle, the prediction means It may be predicted that the host vehicle completes overtaking the preceding vehicle before the vehicle speed of the vehicle increases. On the other hand, when the distance traveled by the host vehicle before the vehicle speed of the preceding vehicle increases is shorter than the distance traveled by the host vehicle before the passing of the preceding vehicle by the host vehicle is completed, the prediction means May predict that the host vehicle will not complete the overtaking of the preceding vehicle before the vehicle speed of the preceding vehicle increases.

<2>
In another aspect of the driving support apparatus of the present invention, the prediction means predicts whether or not the vehicle speed of the front vehicle increases based on the gradient of the driving lane in which the front vehicle is driving. .

  According to this aspect, for example, when the preceding vehicle is traveling on a traveling lane that switches from a flat gradient or an ascending gradient to a descending gradient, the preceding vehicle is traveling on a traveling lane that remains flat or ascending. Compared to the case, it is assumed that the vehicle speed of the forward vehicle is likely to increase after the forward vehicle starts to travel on a downward slope. On the other hand, when the forward vehicle is traveling on a traveling lane that remains ascending or flat, compared to when the preceding vehicle is traveling on a traveling lane that switches from a flat or ascending slope to a descending slope. It is assumed that the vehicle speed of the vehicle ahead is unlikely to increase. Therefore, the predicting unit can preferably predict whether or not the vehicle speed of the preceding vehicle will increase based on the “gradient” that is an example of a road state that may affect the vehicle speed of the preceding vehicle.

<3>
As described above, in another aspect of the driving support apparatus for predicting whether or not the vehicle speed of the preceding vehicle increases based on the gradient of the traveling lane, the predicting means includes the host vehicle overtaking the preceding vehicle. By the time it is completed, it is predicted that the vehicle speed of the vehicle ahead will increase if the vehicle ahead runs downhill.

  According to this aspect, the predicting means can appropriately predict whether or not the vehicle speed of the preceding vehicle will increase based on the gradient of the traveling lane. This is because the vehicle ahead (for example, the vehicle that had been traveling on an uphill or flat slope at the start of overtaking or had not traveled downhill until then) This is because it is assumed that the vehicle speed of the preceding vehicle is likely to increase before the host vehicle completes overtaking the preceding vehicle.

<4>
As described above, in another aspect of the driving support apparatus for predicting whether or not the vehicle speed of the preceding vehicle increases based on the gradient of the traveling lane, the predicting means includes the host vehicle overtaking the preceding vehicle. The vehicle speed of the preceding vehicle increases when the first distance traveled by the host vehicle is equal to or greater than the second distance traveled by the host vehicle before the host vehicle starts traveling on a downward slope. Predict that the situation will be.

  The predicting means can preferably predict whether or not the vehicle speed of the preceding vehicle will increase based on the gradient of the traveling lane. This is because if the first distance is greater than or equal to the second distance, the host vehicle is traveling on an uphill or flat slope at the start of overtaking before the vehicle completes overtaking of the preceding vehicle. It is assumed that there is a high possibility that the preceding vehicle that has not traveled downhill until then) starts traveling on the downhill (as a result, the vehicle speed of the forward vehicle still located in front of the host vehicle increases). Because.

<5>
As described above, in another aspect of the driving support apparatus for predicting whether or not the vehicle speed of the preceding vehicle increases based on the gradient of the traveling lane, the predicting means includes the host vehicle overtaking the preceding vehicle. When the first time required for completion is equal to or longer than the second time required for the host vehicle to start traveling on a downward slope, it is predicted that the vehicle speed of the preceding vehicle will increase.

  The predicting means can preferably predict whether or not the vehicle speed of the preceding vehicle will increase based on the gradient of the traveling lane. This is because, when the first time is equal to or longer than the second time, the host vehicle is traveling on an uphill or flat slope at the start of overtaking before the vehicle completes overtaking of the preceding vehicle. It is assumed that there is a high possibility that the preceding vehicle that has not traveled downhill until then) starts traveling on the downhill (as a result, the vehicle speed of the forward vehicle still located in front of the host vehicle increases). Because.

<6>
In another aspect of the driving assistance apparatus of the present invention, the prediction means predicts whether or not the vehicle speed of the front vehicle increases based on the shape of the traveling lane in which the front vehicle is traveling. .

  According to this aspect, for example, when the forward vehicle is traveling in a traveling lane that is switched from a curved road to a straight road, the forward vehicle is traveling in the traveling lane on the curved road as compared with the traveling forward lane. It is assumed that the vehicle speed of the preceding vehicle is likely to increase after the vehicle starts traveling on a straight road. On the other hand, when the vehicle ahead is traveling on a curved lane, the vehicle speed of the vehicle ahead increases compared to the vehicle traveling on a lane that switches from a curved road to a straight road. It is assumed that it is difficult to do. Therefore, the prediction means can preferably predict whether or not the vehicle speed of the preceding vehicle will increase based on the “shape” that is an example of a road state that can affect the vehicle speed of the preceding vehicle.

<7>
As described above, in another aspect of the driving support apparatus for predicting whether or not the vehicle speed of the preceding vehicle increases based on the shape of the traveling lane, the predicting means includes the host vehicle overtaking the preceding vehicle. By the time it is completed, if the vehicle ahead travels on a straight road, it is predicted that the vehicle speed of the vehicle ahead will increase.

  According to this aspect, the predicting means can appropriately predict whether or not the vehicle speed of the preceding vehicle will increase based on the shape of the traveling lane. This is because the front vehicle (for example, the front vehicle that was traveling on a curved road at the start of overtaking or has not traveled on a straight road) or the own vehicle until the own vehicle completes overtaking of the preceding vehicle. This is because it is assumed that there is a high possibility that the vehicle speed of the preceding vehicle will increase before the host vehicle completes overtaking the preceding vehicle.

<8>
As described above, in another aspect of the driving support apparatus for predicting whether or not the vehicle speed of the preceding vehicle increases based on the shape of the traveling lane, the predicting means includes the host vehicle overtaking the preceding vehicle. The vehicle speed of the preceding vehicle increases when the first distance traveled by the host vehicle by the time it is completed is equal to or greater than the second distance traveled by the host vehicle before the host vehicle starts traveling on a straight road. Predict that the situation will be.

  The predicting means can preferably predict whether or not the vehicle speed of the preceding vehicle will increase based on the shape of the traveling lane. This is because if the first distance is greater than or equal to the second distance, before the host vehicle completes the overtaking of the preceding vehicle, the preceding vehicle (for example, was traveling on a curved road at the start of overtaking or It is assumed that there is a high possibility that the front vehicle that has not traveled on the straight road until the vehicle starts traveling on the straight road (as a result, the vehicle speed of the front vehicle that is still located in front of the vehicle increases). Because.

<9>
As described above, in another aspect of the driving support apparatus for predicting whether or not the vehicle speed of the preceding vehicle increases based on the shape of the traveling lane, the predicting means includes the host vehicle overtaking the preceding vehicle. When the first time required for completion is equal to or longer than the second time required for the host vehicle to start traveling on a straight road, it is predicted that the vehicle speed of the preceding vehicle will increase.

  The predicting means can preferably predict whether or not the vehicle speed of the preceding vehicle will increase based on the shape of the traveling lane. This is because, if the first time is equal to or longer than the second time, the host vehicle (for example, was driving on a curved road at the start of overtaking before or after completing the overtaking of the preceding vehicle). It is assumed that there is a high possibility that the front vehicle that has not traveled on the straight road until the vehicle starts traveling on the straight road (as a result, the vehicle speed of the front vehicle that is still located in front of the vehicle increases). Because.

  The operation and other advantages of the present invention will become more apparent from the following description of the preferred embodiments.

It is a block diagram which shows the structure of the vehicle of this embodiment. It is a top view which shows an example of the driving | running | working condition of a vehicle in case the operation | movement relevant to lane change assist control is performed. It is a top view which shows another example of the driving | running | working condition of a vehicle when the operation | movement relevant to lane change assist control is performed. It is a flowchart which shows the flow of the operation | movement (especially operation | movement relevant to lane change assist control) which the vehicle of this embodiment performs.

  Hereinafter, an embodiment in which a travel support device of the present invention is applied to a vehicle 1 will be described with reference to the drawings.

(1) Configuration of Vehicle First, the configuration of the vehicle 1 of the present embodiment will be described with reference to FIG. FIG. 1 is a block diagram showing an example of the configuration of the vehicle 1 of the present embodiment. FIG. 1 shows the configuration of the vehicle 1 focusing on the configuration requirements related to the present invention for the sake of simplicity. Therefore, it goes without saying that the vehicle 1 may have other constituent requirements than those shown in FIG.

  As shown in FIG. 1, the vehicle 1 includes a GPS receiver 11, a vehicle detector 12, a memory 13, and an ECU (Electronic Control Unit) 100 that is an example of a “driving support device”.

  The GPS receiver 11 receives GPS radio waves radiated from GPS satellites (not shown). The GPS receiver 11 transfers a GPS signal obtained by receiving GPS radio waves to the ECU 100. As a result, the ECU 100 can recognize the current position of the vehicle 1 by analyzing the GPS signal.

  The vehicle detector 12 detects other vehicles (for example, a forward vehicle C2 described later with reference to FIGS. 2 and 3) positioned around the vehicle 1. As the vehicle detector 12, a camera installed at the front, side or rear of the vehicle 1 for photographing other vehicles, a millimeter wave radar for emitting millimeter waves for detecting the presence of other vehicles, An example is an inter-vehicle communication device that detects another vehicle by communicating with another vehicle or a roadside device. The detection result of the vehicle detector 12 (for example, a camera shooting result, a millimeter wave radar detection result, a communication record in an inter-vehicle communication device, etc.) is transferred to the ECU 100. As a result, the ECU 100 can recognize the current position of the other vehicle, the vehicle speed, and the like by analyzing the detection result of the vehicle detector 12.

  The memory 13 is a storage device capable of storing information permanently or temporarily. Examples of the memory 13 include ROM, RAM, flash memory, hard disk, and the like. Particularly in the present embodiment, the memory 13 stores map information. The map information stored in the memory 13 is referred to by the ECU 100 as appropriate. As a result, the ECU 100 can recognize the road condition (for example, lane gradient, lane shape, number of lanes, etc.) at the current position where the vehicle 1 is traveling.

  Note that the ECU 100 may refer to map information downloaded via a network line (not shown) in addition to or instead of the map information stored in the memory 13. In this case, the memory 13 may not store the map information.

  The ECU 100 includes, as a physical processing circuit or a logical processing block, a situation recognition unit 110, a lane change determination unit 120 that is an example of a “prediction unit”, a target track calculation unit 130, “ And a vehicle control unit 140 which is an example of “support means”.

  The situation recognizing unit 110 is based on a GPS signal transferred from the GPS receiver 11 or a detection result of an arbitrary sensor (for example, a vehicle speed sensor) included in the vehicle 1. Recognize the current position. In addition, the situation recognition unit 110 recognizes the running situation of other vehicles located around the vehicle 1 (for example, the current position and the vehicle speed of the other vehicles) based on the detection result of the vehicle detector 12 and the like. In particular, the situation recognition unit 110 travels in front of the vehicle 1 (specifically, in front of the traveling direction) and travels in the travel lane L1 in which the vehicle 1 is currently traveling. It is preferable to recognize the traveling situation (see FIGS. 2 and 3). In addition, the situation recognition unit 110 refers to the map information stored in the memory 13 so that the road condition (for example, the lane of the lane) in which the vehicle 1 is traveling (and the target lane LT) Recognize slope, lane shape, number of lanes, etc.).

  The lane change determination unit 120 determines whether or not the vehicle 1 can change the lane from the currently traveled lane L1 to the target lane LT adjacent to the travel lane L1. At this time, the lane change determination unit 120 is based on at least one of the traveling state of the vehicle 1 recognized by the state recognizing unit 110, the traveling state of the other vehicle, and the road state of the current position where the vehicle 1 is traveling. Then, it is determined whether or not the vehicle 1 can change the lane from the travel lane L1 to the target lane LT. The detailed operation of the lane change determination unit 130 will be described in detail later (see FIG. 4).

  The target trajectory calculation unit 130 calculates a target trajectory T that is a trajectory on which the vehicle 1 should travel. In particular, in the present embodiment, the target trajectory calculation unit 130 is a target trajectory on which the vehicle 1 whose lane is to be changed from the currently traveled lane L1 to the target lane LT (and after the target lane LT has traveled). A target trajectory) T on which the vehicle 1 should travel may be calculated so as to return to the travel lane L1 again. The target trajectory calculation unit 120 is based on, for example, at least one of the travel status of the vehicle 1 recognized by the status recognition unit 110, the travel status of other vehicles, and the road status of the current position where the vehicle 1 is traveling, A target trajectory T is calculated.

  The vehicle control unit 140 performs assist control for supporting the traveling of the vehicle 1. In particular, in the present embodiment, the vehicle control unit 140 changes the lane from the travel lane L1 of the vehicle 1 to the target lane LT so that the vehicle 1 travels along the target track T calculated by the target track calculation unit 130. Assist control for assisting (so-called lane change assist control) is performed.

(2) Operation of Vehicle Next, with reference to FIG. 2 to FIG. 4, an explanation will be given on the operation (particularly, the operation related to the lane change assist control) performed by the vehicle 1 of the present embodiment.

(2-1) Example of Driving Status of Vehicle 1 First, an example of the driving status of the vehicle 1 when an operation related to the lane change assist control is performed will be described with reference to FIGS. 2 and 3. FIG. 2 is a plan view showing an example of a traveling state of the vehicle 1 when an operation related to the lane change assist control is performed. FIG. 3 is a plan view illustrating another example of the traveling state of the vehicle 1 when an operation related to the lane change assist control is performed.

  As shown in the upper part of FIG. 2 and FIG. 3, for example, the vehicle 1 traveling in the travel lane L1 (the own vehicle C1 in FIG. 2 and FIG. 3) is the travel lane one right next to the travel lane L1. When the lane is changed to the target lane LT (see the upper part of FIG. 2 and the route indicated by the alternate long and short dash line in FIG. 3), the operation related to the lane change assist control of this embodiment is performed.

  Such a lane change of the host vehicle C1 is typically a travel lane L1 in which the host vehicle C1 is located in front of the host vehicle C1 along the traveling direction of the host vehicle C1 and the host vehicle C1 is traveling. This is carried out when overtaking the forward vehicle C2 traveling on the vehicle (see the virtual traveling locus of the host vehicle C1 indicated by the upper part of FIG. 2 and the one-dot chain line in FIG. 3). However, the lane change of the host vehicle C1 may be performed under other circumstances. However, it is preferable that the lane change of the host vehicle C1 is performed in a situation where the forward vehicle C2 exists.

  Here, the host vehicle C1 often overtakes the front vehicle C2 in many cases when the vehicle speed V2 of the front vehicle C2 is smaller than the vehicle speed V1 of the host vehicle C1. In other words, the host vehicle C1 overtakes the front vehicle C2, and the host vehicle C1 overtakes the front vehicle C2 when the distance between the host vehicle C1 and the front vehicle C2 is gradually shortened. Many.

  However, as shown in the lower part of FIG. 2, the traveling lane L1 in which the forward vehicle C2 is traveling (that is, the traveling lane L1 in which the host vehicle C1 is traveling) is the traveling lane L1 in which the ascending gradient is switched to the descending gradient. There may be. In such a travel lane L1, the front vehicle C2 that was traveling on the uphill when the host vehicle C1 started overtaking the front vehicle C2 traveled on the downhill while the host vehicle C1 was overtaking. In such a situation, the vehicle speed V2 of the forward vehicle C2 may increase before the host vehicle C1 completes the overtaking of the forward vehicle C2. In such a case, due to the increase in the vehicle speed V2 of the forward vehicle C2, there is a possibility that the overtaking of the forward vehicle C2 by the host vehicle C1 cannot be completed.

  Alternatively, as shown in FIG. 3, the travel lane L1 in which the forward vehicle C2 is traveling (that is, the travel lane L1 in which the host vehicle C1 is traveling) is a travel lane L1 that switches from a curved road to a straight road. There is. Even in such a traveling lane L1, the forward vehicle C2 that was traveling on the curved road when the host vehicle C1 started overtaking the forward vehicle C2 traveled on the straight road while the host vehicle C1 was overtaking. In a situation where the vehicle travels, the vehicle speed V2 of the forward vehicle C2 may increase before the host vehicle C1 completes the overtaking of the forward vehicle C2. In such a case, due to the increase in the vehicle speed V2 of the forward vehicle C2, there is a possibility that the overtaking of the forward vehicle C2 by the host vehicle C1 cannot be completed.

  Therefore, the ECU 100 according to the present embodiment directly determines whether or not the vehicle speed V2 of the front vehicle C2 is increasing during the period from when the own vehicle C1 starts overtaking the front vehicle C2 to when it is completed. Determine indirectly. In other words, the ECU 100 according to the present embodiment is such that the host vehicle C1 cannot complete the overtaking of the front vehicle C2 until the host vehicle C1 completes the overtaking of the front vehicle C2 during the period from the start of the overtaking of the front vehicle C2. It is directly or indirectly determined whether or not the vehicle speed V2 of C2 is increasing. More specifically, for example, the ECU 100 determines that the distance traveled from when the host vehicle C1 starts overtaking the front vehicle C2 to when the host vehicle C1 starts overtaking the front vehicle C2 By determining whether or not the host vehicle C1 is shorter than the distance (distance DS + distance DL in FIGS. 2 and 3) between the vehicle C1 and the start position of the downward slope (or the start position of the straight road) Before completing the overtaking of the preceding vehicle C2, it is indirectly determined whether or not the vehicle speed V2 of the preceding vehicle C2 increases. As a result, when it is determined that the vehicle speed V2 of the preceding vehicle C2 is increasing, the ECU 100 assists the traveling of the host vehicle C1 so that the host vehicle C1 does not change the lane to the target lane LT.

  Hereinafter, the operation of the ECU 100 will be described in more detail with reference to the flowchart shown in FIG.

  2 and 3 merely illustrate an example of the traveling situation, and there is no intention to exclude the presence of vehicles other than the host vehicle C1 and the European vehicle C2. However, it is preferable that the road on which the host vehicle C1 is traveling includes two or more lanes.

  FIG. 2 shows a traveling lane L1 in which the traveling lane L1 in which the forward vehicle C2 is traveling is switched from an ascending gradient to a descending gradient. However, even if the traveling lane L1 in which the forward vehicle C2 is traveling is the traveling lane L1 that switches from a flat gradient to a downward gradient, in some cases, the host vehicle is caused by an increase in the vehicle speed V2 of the forward vehicle C2. There is a possibility that the overtaking of the forward vehicle C2 by C1 cannot be completed. In other words, when the front vehicle C2 traveling on the flat gradient at the time when the host vehicle C1 starts overtaking the front vehicle C2 enters a situation in which the host vehicle C1 is traveling on the downhill while the host vehicle C1 is overtaking. May increase the vehicle speed V2 of the forward vehicle C2. Therefore, even when the traveling lane L1 is switched from the flat gradient to the downward gradient, the same operation as when the traveling lane L1 is switched from the upward gradient to the downward gradient may be performed.

  In the following description, it is assumed that the vehicle speed of the host vehicle C1 is V1 [m / s] and the vehicle speed of the front vehicle C2 is V2 [m / s]. The following description will be given assuming that the inter-vehicle distance between the host vehicle C1 and the preceding vehicle C2 is the current position of the preceding vehicle C2−the current position of the host vehicle C1 = DS [m]. Further, the distance between the preceding vehicle C2 and the starting position of the descending slope (or the starting position of the straight road) is assumed to be the starting position of the descending slope−the current position of the preceding vehicle C2 = DL [m]. Proceed. Any parameter takes a positive value toward the front side in the traveling direction of the host vehicle C1.

(2-2) Flow of Vehicle Operation Next, a flow of an operation (particularly, an operation related to lane change assist control) performed by the vehicle 1 of the present embodiment will be described with reference to FIG. FIG. 4 is a flowchart showing a flow of an operation (particularly, an operation related to lane change assist control) performed by the vehicle 1 of the present embodiment.

  In the following, for the sake of convenience of explanation, the flow of the first operation example performed by the host vehicle C1 in the traveling state shown in FIG. 2 will be described as an example. However, even if the vehicle 1 is different from the own vehicle C1 in the traveling state shown in FIG. 2 (for example, the own vehicle C1 in the traveling state shown in FIG. 3 or the own vehicle C1 in another traveling state), Needless to say, the operations described in (1) may be performed.

  As shown in FIG. 4, first, the situation recognizing unit 110 is based on a GPS signal transferred from the GPS receiver 11 or a detection result of an arbitrary sensor (for example, a vehicle speed sensor) provided in the host vehicle C1. The traveling state of the vehicle C1 (for example, the current position of the host vehicle C1, the vehicle speed V1, etc.) is recognized (step S111).

  Following the operation in step S <b> 111, the situation recognition unit 110 refers to the map information stored in the memory 13. At this time, the situation recognition unit 110 refers to the map information corresponding to the current position of the host vehicle C1 recognized in step S111. As a result, the situation recognition unit 110 recognizes the road state (for example, lane gradient, lane shape, number of lanes, and the like) at the current position where the host vehicle C1 is traveling (step S112).

  Following the operation of step S111 and step S112, before or after or in parallel, the situation recognition unit 110 determines the travel lane L1 in which the host vehicle C1 is traveling based on the detection result of the vehicle detector 12 and the like. The traveling state of the traveling forward vehicle C2 (for example, the current position of the traveling vehicle C2, the vehicle speed V2, etc.) is recognized (step S113).

  Thereafter, the lane change determination unit 120 determines whether or not the lane change trigger is turned on (step S121). The lane change trigger may be turned on, for example, when the direction indicator of the host vehicle C1 is operated (particularly, the direction indicator is operated to indicate the intention to turn to the target lane LT). . Alternatively, the lane change trigger is a time required for the host vehicle C1 to catch up with the preceding vehicle C2 (specifically, the distance between the host vehicle C1 and the preceding vehicle C2 / the vehicle speed V2 of the preceding vehicle C2 as a reference). It may be turned on when the relative vehicle speed of the vehicle C1 = DS / (V1-V2)) is less than a predetermined threshold.

  As a result of the determination in step S121, when it is determined that the lane change trigger is not on (step S121: No), the lane change determination unit 120 indicates that the lane change determination unit 120 indicates that the host vehicle C1 is in the traveling lane. It is determined that the vehicle should continue to travel on L1 as it is (step S123). Therefore, the vehicle control unit 140 performs assist control for assisting the traveling of the host vehicle C1 in the travel lane L1 (step S142). As a result, the host vehicle C1 continues to travel on the travel lane L1.

  On the other hand, as a result of the determination in step S121, when it is determined that the lane change trigger has been turned on (step S121: Yes), the lane change determination unit 120 subsequently causes the host vehicle C1 to lane the target lane LT. It is determined whether or not it can be changed (step S122). More specifically, the lane change determination unit 120 determines whether or not the overtaking of the forward vehicle C2 can be completed after the host vehicle C1 changes the lane to the target lane LT (step S122).

  In step S122, the lane change determination unit 120 is between the start of the overtaking of the preceding vehicle C2 and the completion of the overtaking of the preceding vehicle C2 (that is, before the own vehicle C1 completes the overtaking of the preceding vehicle C2). Whether or not the vehicle speed V2 of the preceding vehicle C2 is increasing may be determined directly or indirectly. In this case, if the vehicle speed V2 of the front vehicle C2 increases before the host vehicle C1 completes the overtaking of the front vehicle C2, the lane change determination unit 120 changes the host vehicle C1 to the target lane LT. It may be determined that the vehicle cannot be overtaken (that is, the overtaking of the forward vehicle C2 cannot be completed after the host vehicle C1 has changed its lane to the target lane LT). This is because when the vehicle speed V2 of the front vehicle C2 increases before the host vehicle C1 completes overtaking of the front vehicle C2, the vehicle speed V2 of the front vehicle C2 increases and the host vehicle C1 and the front vehicle C2 increase. This is because the distance between C2 is difficult to shrink or widens. On the other hand, if the vehicle speed V2 of the front vehicle C2 does not increase before the host vehicle C1 completes the overtaking of the front vehicle C2, the lane change determination unit 120 changes the host vehicle C1 to the target lane LT. (That is, after the host vehicle C1 changes lanes to the target lane LT, the overtaking of the forward vehicle C2 can be completed).

  In the present embodiment, the lane change determination unit 120 determines the distance traveled from when the host vehicle C1 starts overtaking the front vehicle C2 to when the host vehicle C1 starts overtaking the front vehicle C2. It is determined whether or not the distance is shorter than the distance between the host vehicle C1 and the starting position of the downward slope (distance DS + distance DL in FIG. 2). The distance traveled from when the host vehicle C1 starts overtaking the preceding vehicle C2 to when the host vehicle C1 starts passing is between the host vehicle C1 and the starting position of the downward slope when the host vehicle C1 starts passing the preceding vehicle C2. If it is shorter than this distance, it is presumed that the vehicle speed V2 of the front vehicle C2 does not increase before the host vehicle C1 completes the overtaking of the front vehicle C2. As a result, it is determined that the host vehicle C1 can change the lane to the target lane LT (that is, the overtaking of the forward vehicle C2 can be completed after the host vehicle C1 changes the lane to the target lane LT). On the other hand, the distance traveled from when the own vehicle C1 starts overtaking the preceding vehicle C2 to when the own vehicle C1 starts overtaking is the starting position of the descending slope with the own vehicle C1 when the own vehicle C1 starts overtaking the preceding vehicle C2. If the distance between the vehicle and the vehicle is greater than or equal to the distance, the vehicle speed V2 of the front vehicle C2 is estimated to increase before the host vehicle C1 completes the overtaking of the front vehicle C2. As a result, it is determined that the host vehicle C1 cannot change the lane to the target lane LT (that is, the overtaking of the forward vehicle C2 cannot be completed after the host vehicle C1 changes the lane to the target lane LT).

  The determination performed by the lane change determination unit 120 in step S122 will be described in more detail by taking the travel situation shown in FIG. 2 as a specific example.

  As shown in FIG. 2, when the host vehicle C1 overtakes the preceding vehicle C2, the host vehicle C1 (i) performs a first operation of changing the lane from the travel lane L1 to the target lane LT, and (ii) the target lane LT. In many cases, the second operation of pulling out ahead of the forward vehicle C2 by continuing to travel and (iii) the third operation of changing the lane from the target lane LT to the travel lane L1 are performed. Therefore, the following description also assumes that the host vehicle C1 performs the first operation to the third operation.

  First, it is assumed that time TL [second] is required for the first operation in which the host vehicle C1 changes the lane from the travel lane L1 to the target lane LT. Further, it is assumed that the time required for the third operation in which the host vehicle C1 changes the lane from the target lane LT to the travel lane L1 is TL [seconds]. On the other hand, in the second operation of extracting the vehicle ahead of the forward vehicle C2 by continuing to travel in the target lane LT, the distance between the host vehicle C1 and the forward vehicle C2 at the time when overtaking is started / the forward vehicle The relative vehicle speed of the host vehicle C1 based on the vehicle speed V2 of C2 = DS / (V1-V2) [seconds] is required. As a result, it can be seen that the time required for the host vehicle C1 to complete the overtaking of the preceding vehicle C2 is 2 × TL + DS / (V1−V2) [seconds]. Therefore, it can be seen that the distance traveled by the host vehicle C1 until the overtaking of the preceding vehicle C2 is completed is V1 × (2 × TL + DS / (V1−V2)) [m]. Therefore, the distance traveled from when the host vehicle C1 starts overtaking the preceding vehicle C2 to when the host vehicle C1 starts overtaking is equal to the starting position of the host vehicle C1 and the downward slope when the host vehicle C1 starts passing the preceding vehicle C2. In order to be shorter than the distance between the two, it is only necessary to satisfy the formula V1 × (2 × TL + DS / (V1−V2)) <DS + DL. That is, if the formula V1 × (2 × TL + DS / (V1−V2)) <DS + DL is established, the lane change determination unit 120 determines the vehicle speed of the front vehicle C2 before the host vehicle C1 completes the overtaking of the front vehicle C2. It can be determined that there is no situation in which V2 increases. On the other hand, that is, if the mathematical formula V1 × (2 × TL + DS / (V1−V2)) <DS + DL is not established, the lane change determination unit 120 is performed. It can be determined that the vehicle speed V2 of the forward vehicle C2 is increasing before the host vehicle C1 completes the overtaking of the forward vehicle C2.

  The parameters V1 and V2 described above can be recognized by the situation recognition unit 110 based on the detection result of an arbitrary sensor (for example, a vehicle speed sensor) provided in the vehicle 1, the detection result of the vehicle detector 12, and the like. (Step S111 and Step S113 in FIG. 4). Similarly, the parameters DS and DL described above can be recognized by the situation recognition unit 110 based on the map information stored in the memory 13 (step S112 in FIG. 4). Therefore, the lane change determination unit 120 can suitably perform the determination in step S122 using these parameters recognized by the situation recognition unit 110.

  This will be described in more detail by taking specific numerical values as examples. The vehicle speed V1 of the host vehicle C1 is “80 km / h (that is, 22.2 m / s)”, and the vehicle speed V2 of the preceding vehicle C2 is “70 km / h (that is, 19.42 m / s)” and the lane is changed. It is assumed that the time TL required for each of the first operation and the third operation to be performed is “6 [seconds]”, and the distance DS between the host vehicle C1 and the preceding vehicle C2 is “50 [m]”. In this case, the distance traveled by the host vehicle C1 from the start of overtaking the preceding vehicle C2 to the completion thereof is V1 × (2 × TL + DS / (V1−V2)) = 22.2 × (2 × 6 + 50 / ( 22.2-19.42)) = 665.6 [m]. Therefore, if the distance DS + DL between the own vehicle C1 and the starting position of the downward gradient at the time when the own vehicle C1 starts overtaking the forward vehicle C2 is longer than 665.6 m, the lane change determination unit 120 It can be determined that the vehicle speed V2 of the front vehicle C2 does not increase before C1 completes the overtaking of the front vehicle C2. As a result, the lane change determination unit 120 can change the own vehicle C1 to the target lane LT (that is, after the own vehicle C1 changes the lane to the target lane LT, the overtaking of the preceding vehicle C2 can be completed. May be determined). On the other hand, if the distance DS + DL between the own vehicle C1 and the starting position of the descending slope is not longer than 665.6 m when the own vehicle C1 starts overtaking the forward vehicle C2, the lane change determination unit 120 It can be determined that the vehicle speed V2 of the forward vehicle C2 is increasing before the host vehicle C1 completes the overtaking of the forward vehicle C2. As a result, the lane change determination unit 120 cannot complete the overtaking of the preceding vehicle C2 after the own vehicle C1 cannot change the lane to the target lane LT (that is, after the own vehicle C1 changes the lane to the target lane LT). It may be determined that it is not possible.

  In the above description, the lane change determination unit 120 determines that the distance traveled from when the own vehicle C1 starts overtaking the front vehicle C2 to when the own vehicle C1 starts overtaking the front vehicle C2. It is determined whether or not the distance is shorter than the distance between the host vehicle C1 and the starting position of the downward slope. However, the time required for the lane change determination unit 120 to be completed after the own vehicle C1 starts overtaking the forward vehicle C2 is less than the time the own vehicle C1 starts overtaking the forward vehicle C2. It may be determined whether or not it is shorter than the time required to start traveling on the gradient. The time required from when the host vehicle C1 starts overtaking the forward vehicle C2 to the completion is the time required for the host vehicle C1 to start following the forward vehicle C2 and before the front vehicle C2 starts traveling on a downward slope. If shorter than that, it is presumed that the vehicle speed V2 of the forward vehicle C2 does not increase before the host vehicle C1 completes overtaking of the forward vehicle C2. As a result, it is determined that the host vehicle C1 can change the lane to the target lane LT (that is, the overtaking of the forward vehicle C2 can be completed after the host vehicle C1 changes the lane to the target lane LT). On the other hand, the time required from when the host vehicle C1 starts overtaking the forward vehicle C2 to when the host vehicle C1 starts to pass is from when the host vehicle C1 starts overtaking the forward vehicle C2 until the front vehicle C2 starts traveling on a downward slope. If the time required for this is exceeded, it is estimated that the vehicle speed V2 of the forward vehicle C2 increases before the host vehicle C1 completes the overtaking of the forward vehicle C2. As a result, it is determined that the host vehicle C1 cannot change the lane to the target lane LT (that is, the overtaking of the forward vehicle C2 cannot be completed after the host vehicle C1 changes the lane to the target lane LT).

  In FIG. 4 again, when it is determined as a result of the determination in step S122 that the own vehicle C1 cannot be changed to the target lane LT (No in step S122), the lane change determination unit 120 determines that the own vehicle C1 Determines that the lane should not be changed with respect to the target lane LT (step S123). That is, the lane change determination unit 120 determines that the host vehicle C1 should continue to travel on the travel lane L1 (step S123). Therefore, the vehicle control unit 140 performs assist control for assisting the traveling of the host vehicle C1 in the travel lane L1 (step S142). As a result, the host vehicle C1 continues to travel on the travel lane L1.

  On the other hand, as a result of the determination in step S122, when it is determined that the host vehicle C1 can change the lane to the target lane LT (step S122: Yes), the lane change determination unit 120 determines that the host vehicle C1 is the target lane. It is determined that the lane may be changed with respect to the lane LT (step S124). In this case, the target trajectory calculation unit 130 calculates the target trajectory T of the host vehicle C1 that changes lanes (step S131). For example, the target track calculation unit 130 changes the lane from the travel lane L1 to the target lane LT, the first start point and the first end point of the first motion and the third lane change from the target lane LT to the travel lane L1. The third start point and the third end point are calculated. In this case, the target trajectory calculation unit 130 considers the vehicle speed V1 of the host vehicle C1, the time required for the lane change, and the like, and the first start point and the first start point that can realize an appropriate (in other words, safe) lane change. One end point, a third start point, and a third end point may be calculated. Thereafter, the target trajectory calculation unit 130 calculates a target trajectory T that passes through the first start point, the first end point, the third start point, and the third end point in this order. In this case, the target track calculation unit 130 determines a travel route in which acceleration (for example, lateral acceleration and vertical acceleration) applied to the host vehicle C1 as the lane changes become as small as possible (preferably minimized), The target trajectory T may be calculated.

  Thereafter, the vehicle control unit 140 performs assist control (so-called lane change assist control) for assisting the lane change of the host vehicle C1 to the target lane LT (step S141). That is, the vehicle control unit 140 performs lane change assist control so that the host vehicle C1 travels along the target track T calculated in step S131. As a result, the host vehicle C1 travels so as to change the lane with respect to the target lane LT and pass the preceding vehicle C2.

  As described above, in the present embodiment, the ECU 100 determines that the host vehicle C1 is only in the case where the host vehicle C1 is predicted to be able to pass the preceding vehicle C2 based on the road state (for example, gradient or shape). The traveling of the host vehicle C1 is supported so as to change lanes in order to pass the preceding vehicle C2. That is, when it is predicted that the own vehicle C1 cannot pass the preceding vehicle C2 based on the road condition (for example, the gradient or shape), the ECU 100 does not change the lane (that is, the vehicle is currently traveling). As a result, the host vehicle C1 supports the travel of the host vehicle C1 so as to continue to travel 9. As a result, the host vehicle C1 changes little or no useless lane. The lane change of the host vehicle C1 can be favorably supported.

  The present invention is not limited to the above-described embodiment, and can be changed as appropriate without departing from the scope or spirit of the invention that can be read from the claims and the entire specification. Is also included in the technical scope of the present invention.

1 Vehicle 11 GPS Receiver 12 Vehicle Detector 13 Memory 100 ECU
DESCRIPTION OF SYMBOLS 110 Situation recognition part 120 Lane change determination part 130 Target track calculation part 140 Vehicle control part C1 Own vehicle C2 Front vehicle L1 Traveling lane LT Target lane

Claims (9)

A driving support device that supports lane change of the host vehicle,
Predicting means for predicting whether or not the vehicle speed of the preceding vehicle will increase based on the road condition of the traveling lane in which the preceding vehicle traveling ahead of the host vehicle is traveling;
When it is predicted that the vehicle speed of the preceding vehicle will increase, the driving support device further comprises support means for supporting the traveling of the host vehicle so as not to change the lane of the host vehicle. .   2. The travel according to claim 1, wherein the predicting unit predicts whether or not the vehicle speed of the front vehicle increases based on a gradient of a travel lane in which the front vehicle is traveling. Support device.   The predicting means predicts that the vehicle speed of the front vehicle is increased when the front vehicle is traveling downhill before the host vehicle completes overtaking the front vehicle. The travel support apparatus according to claim 2, wherein   The predicting means is configured such that the first distance traveled by the host vehicle before the host vehicle completes overtaking of the preceding vehicle is the second distance by which the host vehicle travels before the host vehicle starts traveling on a downward slope. The driving support device according to claim 2, wherein when the distance is greater than or equal to the distance, it is predicted that the vehicle speed of the preceding vehicle increases.   When the first time required for the own vehicle to complete overtaking the preceding vehicle is equal to or longer than the second time required for the own vehicle to start traveling on a downward slope, the predicting means The driving support device according to any one of claims 2 to 4, wherein the vehicle speed is predicted to increase.   6. The prediction unit according to claim 1, wherein the prediction unit predicts whether or not the vehicle speed of the front vehicle increases based on a shape of a traveling lane in which the front vehicle is traveling. The driving support device according to claim 1.   The predicting means predicts that the vehicle speed of the front vehicle is increased when the front vehicle travels on a straight road before the host vehicle completes overtaking of the front vehicle. The travel support apparatus according to claim 6.   The prediction means is configured such that the first distance traveled by the host vehicle before the host vehicle completes overtaking of the preceding vehicle is the second distance that the host vehicle travels before the host vehicle starts traveling on a straight road. The travel support apparatus according to claim 6 or 7, wherein when the distance is greater than or equal to the distance, the vehicle speed of the preceding vehicle is predicted to increase.   When the first time required for the host vehicle to complete overtaking the preceding vehicle is equal to or longer than the second time required for the host vehicle to start traveling on a straight road, the predicting means The driving support device according to any one of claims 6 to 8, wherein the vehicle speed is predicted to increase.

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