JP2018005827A - Lane change support device and lane change support method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a lane change support device and a lane change support method capable of supporting lane change without impairing driver's comfort.SOLUTION: A lane change support device according to the embodiment comprises a search section, a prediction section, a determination section and a support section. The search section searches for a space that is to be a candidate of a lane change destination of an own vehicle. The prediction section predicts a state of the own vehicle when the own vehicle changes a lane to the space on the basis of surroundings of the space searched for by the search section. The determination section determines whether the space is proper as the lane change destination on the basis of the state predicted by the prediction section. The support section supports driving in accordance with a determination result by means of the determination section.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a lane change support device and a lane change support method.

  Conventionally, when a lane change of the host vehicle is necessary, there is an apparatus that supports a lane change to an adjacent lane (see, for example, Patent Document 1).

JP 2006-113918 A

  However, when the lane is changed to the adjacent lane according to the assistance, the driver's comfort may be impaired.

  The present invention has been made in view of the above, and an object of the present invention is to provide a lane change support device and a lane change support method that can support lane change without impairing driver comfort.

  In order to solve the above-described problems and achieve the object, a lane change support device according to the present invention includes a search unit, a prediction unit, a determination unit, and a support unit. A search part searches for the space used as the candidate of the lane change destination of the own vehicle. The prediction unit predicts the situation of the host vehicle when the host vehicle changes lanes to the space based on the situation around the space searched by the search unit. The determination unit determines whether or not the space is appropriate as a lane change destination based on the situation predicted by the prediction unit. The support unit supports driving according to the determination result of the determination unit.

  ADVANTAGE OF THE INVENTION According to this invention, a lane change can be supported without impairing a driver | operator's comfort.

Drawing 1 is an explanatory view showing an outline of a lane change support method concerning an embodiment. FIG. 2 is a block diagram illustrating a configuration of the lane change support device according to the embodiment. FIG. 3 is a diagram showing the operation content for predicting the situation of visibility in front of the host vehicle. FIG. 4 is a diagram illustrating the operation content for predicting the field of view based on the height of the other vehicle. FIG. 5 is a diagram showing the operation content (part 1) for predicting the situation behind the host vehicle. FIG. 6 is a diagram showing the operation content (part 2) for predicting the situation behind the host vehicle. FIG. 7 is a diagram showing the operation content for predicting the situation ahead of the host vehicle. FIG. 8 is a flowchart illustrating a processing procedure executed by the control unit of the lane change support device according to the embodiment. FIG. 9 is a flowchart (part 1) illustrating a processing procedure of a prediction process executed by the control unit according to the embodiment. FIG. 10 is a flowchart (part 2) illustrating a processing procedure of a prediction process executed by the control unit according to the embodiment.

  Hereinafter, embodiments of a lane change support device and a lane change support method disclosed in the present application will be described in detail with reference to the accompanying drawings. In addition, this invention is not limited by this embodiment.

  First, the lane change support method according to the embodiment will be described with reference to FIG. FIG. 1 is an explanatory diagram illustrating a lane change support method performed by the lane change support device 1 according to the embodiment.

  Here, for example, when the own vehicle C is a normal vehicle, and the large vehicle 50 and another ordinary vehicle 51 are traveling in the adjacent lane of the lane in which the own vehicle C is traveling, the lane change support device 1 performs the lane change. A support method will be described. In addition, suppose that space S1-S3 where the own vehicle C can change lanes exists between each vehicle of an adjacent lane.

  In such a situation, if the own vehicle C changes the lane to the space S1, the driver of the own vehicle C in the space S1 will be positioned directly behind the large vehicle 50 after changing the lane. There is a risk that the forward visibility may be hindered or a feeling of pressure may be felt, and comfort may be impaired.

  Therefore, the lane change support device 1 according to the embodiment pre-reads the situation assumed after the lane change before the lane change. Specifically, the lane change support device 1 first searches for a space that is a candidate for a lane change destination of the host vehicle C. In the example of FIG. 1, there are spaces S <b> 1 to S <b> 3 (hereinafter may be collectively referred to as a space S) as lane change destination candidates.

  Subsequently, the lane change assist device 1 predicts the situation of the host vehicle C when the host vehicle C changes the lane to the spaces S1 to S3 based on the situation around the searched spaces S1 to S3. Subsequently, the lane change support device 1 determines whether or not the spaces S1 to S3 are appropriate as lane change destinations based on the predicted situation. The lane change assisting device 1 assists driving according to the determination result.

  For example, the lane change assisting apparatus 1 predicts that the large vehicle 50 has poor visibility in front of the host vehicle C when the space S1 is a candidate for the lane change destination. For this reason, the lane change assist device 1 determines that the space S1 is not appropriate as a lane change destination, and urges the driver to cancel the lane change to the space S1, for example, by alerting the driver.

  In this way, the lane change assist device 1 according to the embodiment predicts the situation of the host vehicle C that is assumed after the lane change, and performs support according to the situation, so that the driver's comfort is not impaired. Can support change.

  Further, the lane change assisting apparatus 1 predicts that, for example, when the space S2 is a candidate for the lane change destination, for example, another ordinary vehicle 51 does not obstruct the field of view ahead of the host vehicle C. For this reason, the lane change support device 1 determines that the space S2 is appropriate as a lane change destination, and performs assistance such as a steering wheel operation for changing the lane, for example.

  The lane change assisting apparatus 1 predicts that the large vehicle 50 approaches the space S3 from the rear by determining the deceleration performance of the large vehicle 50, for example, when the space S3 is a candidate for the lane change destination. It is determined that the space S3 is not appropriate as a lane change destination.

  In addition, as shown in FIG. 1, the lane change assistance apparatus 1 determines the priority provided to a driver | operator as a lane change destination, when there are multiple spaces S1-S3. This point will be described later.

  Next, the configuration of the lane change support device 1 according to the embodiment will be described in detail with reference to FIG. FIG. 2 is a block diagram illustrating a configuration of the lane change support device 1 according to the embodiment. As shown in FIG. 2, the lane change assist device 1 includes, for example, a direction indicator 11, a radar device 12, a camera 13, a navigation device 14, an inter-vehicle communication device 15, an in-vehicle sensor 16, an output device 17, and a vehicle control device 18. Connected.

  The direction indicator 11 is a switch for turning on the turn signal lamp of the host vehicle C, accepts the switch operation as a lane change from the driver, and outputs it to the lane change support device 1.

  The radar device 12 is a millimeter wave radar, for example, and detects an object existing around the host vehicle C. The radar device 12 outputs information such as the relative position and relative speed between the detected object and the host vehicle C to the lane change support device 1.

  The camera 13 includes, for example, an image sensor such as a charge coupled device (CCD) or a complementary metal oxide semiconductor (CMOS), and images the surroundings of the host vehicle C using the image sensor. The camera 13 outputs the captured image of the periphery of the host vehicle C to the lane change device 1.

  The navigation device 14 specifies the current position of the host vehicle C by radio waves from, for example, a GPS (Global Positioning System) artificial satellite, and uses the current position and map information including electronic map data to thereby determine the travel route. Provide guidance and guidance.

  In addition to the electronic map data, the map information includes, for example, road type information and information related to road information items such as road signs and traffic lights. The navigation device 14 outputs various types of information including the position of the host vehicle C, the travel route, and map information to the lane change support device 1.

  The inter-vehicle communication device 15 is a communication device that communicates with another vehicle 50 existing around the host vehicle C, for example. For example, the inter-vehicle communication device 15 communicates with an inter-vehicle communication device mounted on another vehicle, thereby acquiring the loading information regarding the type of the other vehicle, the load of the other vehicle, and the like, and outputting the information to the lane change assisting device 1.

  The in-vehicle sensor 16 is a sensor that detects the behavior of the host vehicle C, and is, for example, a vehicle speed sensor that detects the host vehicle speed, a gyro sensor that detects an inclination of the host vehicle C, or the like. The in-vehicle sensor 16 outputs information indicating the detected behavior of the host vehicle C to the lane change support device 1.

  The output device 17 is an in-vehicle display or a speaker, for example, and alerts the user with a display or sound indicating the relative positions of the spaces S1 to S3. The vehicle control device 18 is a control device that controls the behavior of the vehicle such as an accelerator, a brake, and a handle operation of the host vehicle C, for example.

  The lane change support device 1 includes a control unit 2 and a storage unit 3. The storage unit 3 stores setting information 31. The setting information 31 is information including setting values related to the type of the host vehicle C and the characteristics of the driver. The setting information 31 includes, for example, information on the acceleration performance and deceleration performance of the host vehicle C, the vehicle size, and the driver's line-of-sight position.

  The storage unit 3 is a semiconductor memory device such as a RAM (Random Access Memory) or a flash memory, or a storage device such as an HDD (Hard Disk Drive) or an optical disk.

  The control unit 2 includes, for example, a microcomputer having a central processing unit (CPU), a read only memory (ROM), a random access memory (RAM), an input / output port, and various circuits.

  The control unit 2 includes a search unit 21, a prediction unit 22, a determination unit 23, a rank determination unit 24, and a support unit 25. The functions of the search unit 21, the prediction unit 22, the determination unit 23, the order determination unit 24, and the support unit 25 are realized by, for example, the CPU reading and executing a program stored in the storage unit 3.

  The search unit 21, the prediction unit 22, the determination unit 23, the order determination unit 24, and the support unit 25 are each partially or entirely hardware such as ASIC (Application Specific Integrated Circuit) or FPGA (Field Programmable Gate Array). It may be configured. Hereinafter, the search unit 21, the prediction unit 22, the determination unit 23, the order determination unit 24, and the support unit 25 will be described.

  For example, when the direction indicator 11 is operated by a driver, the search unit 21 searches for a space S that is a candidate for a lane change destination of the host vehicle C. For example, the search unit 21 searches for a space corresponding to the length of the host vehicle C in the lane adjacent to the lane in which the host vehicle C travels based on the length (for example, the total length) of the host vehicle C. The search unit 21 outputs the space S detected by searching to the prediction unit 22.

  In addition, although the search part 21 made the operation of the direction indicator 11 by a driver the trigger of a search start, the trigger of a search start is not restricted to this. The search part 21 is good also as specifying the timing which starts lane change based on the driving | running route set by the navigation apparatus 14, for example, and making the specified timing a trigger of a search start.

  The prediction unit 22 predicts the situation of the host vehicle C when the host vehicle C changes the lane to the space S based on the situation around the space S searched by the search unit 21.

  For example, the prediction unit 22 uses the setting information 31 stored in the storage unit 3 to predict the situation of the forward visibility in the space S and the situation of other vehicles in front of or behind the space S. The specific operation content by the prediction unit 22 will be described later with reference to FIG.

  The determination unit 23 determines whether the space S is appropriate as a lane change destination based on the situation predicted by the prediction unit 22. The specific operation content by the determination unit 23 will be described later with reference to FIG.

  The priority determination unit 24 provides priority to the driver as a lane change destination for each space S based on the situation predicted by the prediction unit 22 when there are a plurality of spaces S searched by the search unit 21. Determine the ranking.

  For example, when the order determination unit 24 predicts that the field of view is poor by the prediction unit 22 to be described later, or when it is predicted that another vehicle existing in front of or behind the space S approaches within a predetermined distance. , Lower the priority.

  Thereby, when supporting by the support unit 25 later, for example, it is possible to support to change the lane in priority to the space S having higher priority.

  The support unit 25 performs driving support according to the determination result of the determination unit 23. For example, the support unit 25 controls the accelerator opening and the brake amount so as to match the speed of the surrounding vehicle and the control for reducing the handle operation load in the direction of the space S determined to be appropriate by the determination unit 23. Lane control is assisted by adjusting the control.

  Thereby, since the support part 25 makes a driver | operator's lane change easy, it can assist a lane change, without impairing comfort.

  On the other hand, when the determination unit 23 determines that the space S is not appropriate as the lane change destination, the support unit 25 calls at least one of alerting the lane change to the space S and reexamining the lane change destination. Do.

  Specifically, the support unit 25, for example, alerts the driver in advance by notifying the predicted situation, and reexamines whether there is another space S suitable as a lane change destination. And provide support for suggesting alternative candidates.

  Thereby, when changing the lane to the space S that is not appropriate as a lane change destination, the support unit 25 can reduce the driver's confusion due to a poor visibility or the like after the lane change. Further, the support unit 25 can provide support for avoiding a situation such as poor visibility by proposing another candidate.

  Next, specific operation contents of the prediction unit 22 will be described with reference to FIG. First, with reference to FIG. 3, description will be given of operation contents for predicting the state of view by the prediction unit 22. FIG. 3 is a diagram showing the operation content for predicting the situation of visibility in front of the host vehicle. FIG. 3 shows a case where the large vehicle 50 is traveling in front of the space S and the traffic light 100 is present in front of the large vehicle 50.

  In such a situation, when the host vehicle C changes lanes to the space S, the large vehicle 50 blocks the view in front of the host vehicle from the position of the space S, and the driver of the host vehicle C may overlook the traffic light 100. There is.

  Therefore, the prediction unit 22 predicts the situation of the field of view in front of the host vehicle when the host vehicle C changes the lane to the space S based on the size of the other vehicle (large vehicle 50) traveling in front of the space S. For example, the prediction unit 22 predicts the situation of the field of view ahead of the host vehicle based on the height of the large vehicle 50 traveling forward.

  Here, the operation content for predicting the situation of the field of view of the front of the driver's own vehicle based on the height of the large vehicle 50 traveling ahead will be described with reference to FIG.

  FIG. 4 is a diagram illustrating the operation content for predicting the state of view based on the height of the other vehicle. FIG. 4 shows a positional relationship among the host vehicle C, the large vehicle 50, and the traffic light 100 in the situation shown in FIG. Moreover, in FIG. 4, the own vehicle C after changing the lane to the space S is indicated by a broken line.

  Here, it is assumed that the “traffic signal height H1” is the height to the position of the lower end of the traffic signal 100 to be visually observed. The “traffic height H1” may be a height between a position from the lower end position to a position near the upper end.

  Further, “visual height H2” is a height at which visual observation from the host vehicle C is possible, and “viewpoint height h1” is the height of the viewpoint of the driver of the host vehicle C, “H2” is the height of the large vehicle 50 traveling in front of the host vehicle C.

  Further, the “line-of-sight angle θ” is the elevation angle of the line-of-sight to the upper end of the large vehicle 50, and the “viewpoint distance d” is the distance from the rear end of the large vehicle 50 to the viewpoint of the driver of the host vehicle C. It is assumed that the “object distance D” is the distance t seconds before reaching the traffic signal 100.

  The prediction unit 22 acquires “viewpoint height h <b> 1” from the setting information 31. Further, the prediction unit 22 acquires “the traffic light height H1”, “the other vehicle height h2”, and “the viewpoint distance d” from the navigation device 14, the inter-vehicle communication device 15, the in-vehicle sensor 16, and the like.

Further, the prediction unit 22 calculates the “object distance D” by multiplying the speed of the host vehicle C and the time t at which the vehicle 100 arrives. Further, the prediction unit 22 calculates the “line-of-sight angle θ” by the following formula (1) using the “viewpoint height h1”, “other vehicle height h2”, and “viewpoint distance d”.

Further, the prediction unit 22 calculates the “viewing height H2” by the following equation (2) using the “object distance D”, “sight line angle θ”, and “viewpoint height h1”.

  As illustrated in FIG. 4, the determination unit 23 determines whether or not the traffic light 100 can be visually recognized at a time point t seconds before passing through the traffic light 100. Specifically, the determination unit 23 determines that the field of view is poor when the “visual height H2” is equal to or greater than the “traffic light height H1”. On the other hand, the determination unit 23 determines that the field of view is good when the “visual height H2” is less than the “traffic height H1”.

  Subsequently, the determination unit 23 determines that the space S is appropriate as a lane change destination when the visibility is good. And the support part 25 assists a lane change by controlling a steering wheel, an accelerator, a brake, etc., for example.

  On the other hand, the determination unit 23 determines that the space S is not appropriate as a lane change destination when the visibility is poor. Then, the support unit 25 performs alerting for notifying that the lane change is to be performed while further increasing the inter-vehicle distance from the large vehicle 50, and reexamines the space S.

  Thus, the driver of the host vehicle C can drive comfortably because the target such as the traffic light 100 is not overlooked after the lane change. The time t before passing the traffic light 100, which is the visibility determination timing of the visibility by the prediction unit 22, may be a fixed value or may be a value that can be changed according to the driving characteristics of the driver.

  Further, the “traffic light height H1” is not limited to the case of acquiring from the navigation device 14, and for example, the height of the traffic light 100 assumed in advance according to the type of road (general road or highway) is stored. It is good.

  Moreover, although it mentioned as an example of the object which visually observes the traffic signal 100, it is not limited to this, For example, what is necessary is just a target which should be visually recognized for drivers, such as a road sign and a guidance signboard.

  Next, another situation predicted by the prediction unit 22 will be described with reference to FIGS. FIG. 5 is a diagram showing the operation content (part 1) for predicting the situation behind the host vehicle C. Here, the case where the large vehicle 50 is traveling behind the space S will be described.

  Here, the large vehicle 50 such as a truck has a deceleration performance slower than that of a normal vehicle due to the weight of the vehicle, that is, the travel distance required to decelerate to a predetermined speed may be longer than that of the normal vehicle. It is common.

  For this reason, even if the own vehicle C changes the lane to the space S in a state where there is a sufficient distance L between the large vehicle 50 and the vehicle L, the distance L between the vehicles will be clogged. Must accelerate rapidly. As a result, the driver's comfort is impaired after the lane change.

  Therefore, the prediction unit 22 predicts the situation behind the host vehicle C when the host vehicle C changes the lane to the space S based on the deceleration performance of the other vehicle traveling behind the space S before the lane change.

Specifically, the prediction unit 22 calculates the deceleration performance of the other vehicle as the acceleration A at time t by the following formula (3) using the acceleration change rate J and the predetermined coefficient F of the other vehicle.

  The prediction unit 22 acquires the acceleration change rate J based on, for example, images of the radar device 12 and the camera 13. The prediction unit 22 determines a predetermined coefficient F according to the type of the other vehicle. For example, the prediction unit 22 determines that the coefficient F is less than 1 when the type of the other vehicle is the large vehicle 50, and the coefficient F is 1 when the other vehicle is other than the large vehicle 50 such as a normal vehicle.

Further, the prediction unit 22 calculates the relative speed V with respect to the large vehicle 50 at time t by the following equation (4).

Further, the prediction unit 22 calculates a time t until the relative speed V reaches zero by the following equation (5). Equation (5) can be obtained by substituting Equation (3) into Equation (4) above.

  Further, the prediction unit 22 calculates a required distance, which is a required travel distance until the relative speed reaches zero, using the time t calculated by the equation (5) and the speed of the large vehicle 50. Note that the prediction unit 22 calculates the necessary distance as an integral value of the speed of the large vehicle 50 from the start of deceleration of the large vehicle 50 to time t.

  The prediction unit 22 compares the calculated required distance with the inter-vehicle distance L from the space S to the large vehicle 50. And when the required distance is longer than the inter-vehicle distance L, the prediction unit 22 predicts that the large vehicle 50 approaches from the rear.

  Then, when the predicting unit 22 predicts that the large vehicle 50 is approaching from behind, the determining unit 23 determines that the space S is not appropriate, and notifies the support unit 25 that the lane is changed while accelerating, for example. Let them be alerted.

  As described above, the predicting unit 22 can prevent the inter-vehicle distance from the own vehicle C from being clogged after changing the lane by predicting that the slowly decelerating large vehicle 50 approaches the own vehicle C. You can drive.

  In addition, although the prediction part 22 determined the coefficient F based on the type of other vehicles, it is not limited to this, For example, in addition to the type of other vehicles, the loading information of the other vehicles acquired by the inter-vehicle communication apparatus 15, for example. The coefficient F may be determined in consideration of

  For example, the prediction unit 22 makes the coefficient F smaller when the loading amount of the other vehicle is a predetermined amount or more than when it is less than the predetermined amount. As a result, even if the type is the same, the required distance can be long estimated in the case of a vehicle having a large load and heavy vehicle weight.

  In addition, in FIG. 5, although the other vehicle was the large vehicle 50 and the case where the own vehicle C was a normal vehicle was demonstrated, it is not limited to this. Next, the case where the other vehicle is a normal vehicle and the host vehicle C is a large vehicle will be described with reference to FIG.

  FIG. 6 is a diagram showing the operation content (part 2) for predicting the situation behind the host vehicle C. FIG. 6 shows a case where the host vehicle C equipped with the lane change assist device 1 is a large vehicle and the other vehicle is a normal vehicle 51. Further, it is assumed that the ordinary vehicle 51 has a high relative speed with the host vehicle C, that is, is approaching the space S.

  Here, when the host vehicle C, which is a large vehicle, accelerates, the acceleration performance is generally lower than that of the ordinary vehicle 51, that is, it takes time to accelerate. For this reason, even if the lane is changed in a state where the inter-vehicle distance L from the space S to the ordinary vehicle 51 is sufficient, if the acceleration takes time, the inter-vehicle distance L may not be sufficient.

  Therefore, when the host vehicle C is a large vehicle, the prediction unit 22 predicts a rear situation in consideration of the acceleration performance of the host vehicle C in addition to the deceleration performance of the other vehicle. Specifically, the prediction unit 22 calculates a necessary distance, which is a necessary travel distance until the relative speed reaches zero, by the same method as described above. The acceleration performance is calculated by the above equation (3) using a coefficient F corresponding to the type of the host vehicle C.

  The prediction unit 22 compares the calculated required distance with the inter-vehicle distance L from the space S to the ordinary vehicle 51. And when the required distance is longer than the inter-vehicle distance L, the prediction unit 22 predicts that the ordinary vehicle 51 approaches from the rear.

  Subsequently, the determination unit 23 determines that the space S is not appropriate when the prediction unit 22 predicts that the ordinary vehicle 51 approaches from behind. Subsequently, the support unit 25 performs alerting for notifying that the lane change is to be made after the rear ordinary vehicle 51 has passed the host vehicle C, for example.

  In this way, the prediction unit 22 considers that the acceleration of the host vehicle C is moderate, and predicts that the ordinary vehicle 51 approaches the host vehicle C, so that the inter-vehicle distance from the host vehicle C after the lane change Since it is possible to prevent L from being clogged, it is possible to drive comfortably.

  Next, with reference to FIG. 7, the operation content in which the prediction unit 22 predicts the situation in consideration of the acceleration performance of the host vehicle C when the host vehicle C is a large vehicle will be described.

  FIG. 7 is a diagram illustrating the operation content for predicting the situation in front of the host vehicle C. FIG. 7 shows a scene where the large vehicle 50 travels in front of the host vehicle C on an uphill road.

  Here, as described above, the large vehicle 50 takes time to accelerate to a predetermined speed, that is, the acceleration performance difference from the own vehicle C which is a normal vehicle is large. Further, in the situation where the vehicle travels on the uphill road shown in FIG. 7, the acceleration performance difference is further widened.

  For this reason, if the host vehicle C changes its lane to the space S4 behind the large vehicle 50, the host vehicle C must accelerate in accordance with the acceleration performance of the large vehicle 50, which may cause irritation to the driver. Further, for example, if the inter-vehicle distance L between the space S4 and the large vehicle 50 is clogged, the forward visibility becomes poor.

  Therefore, the prediction unit 22 predicts the situation in front of the host vehicle C when the host vehicle C changes the lane to the space S4 based on the acceleration performance of the other vehicle traveling in front of the space S4 before the lane change.

  Specifically, based on the acceleration performance of the large vehicle 50, the prediction unit 22 calculates a necessary distance, which is a necessary travel distance until the relative speed reaches zero, by the same method as described above. The acceleration performance is calculated by the above equation (3) using the coefficient F corresponding to the large vehicle 50.

  The prediction unit 22 compares the calculated required distance with the inter-vehicle distance L from the space S4 to the ordinary vehicle 51. For example, when the required distance is longer than the inter-vehicle distance L, the prediction unit 22 predicts that the host vehicle C approaches the large vehicle 50 ahead.

  Then, the determination unit 23 determines that the space S is not appropriate when the prediction unit 22 predicts that the ordinary vehicle 51 approaches from behind. And the support part 25 performs alerting etc. which notify that it changes lanes behind the large vehicle 51, for example, decelerating.

  In the situation shown in FIG. 7, the prediction unit 22 may predict whether it is possible to change the lane to the space S5 after overtaking the large vehicle 50.

  Specifically, the prediction unit 22 predicts by calculating an overtaking time necessary for overtaking the large vehicle 50 within a speed limit corresponding to the type of road, for example. The prediction unit 22 calculates the overtaking time using, for example, the speed difference between the host vehicle C and the large vehicle 50 and the distance to the space S.

  The prediction unit 22 compares the calculated overtaking time with the time t until the relative speed V calculated by the above equation (5) becomes zero. For example, when the overtaking time is shorter than the time t, the prediction unit 22 predicts that the host vehicle C can overtake the large vehicle 50.

  Thus, since the own vehicle C can travel without matching the acceleration performance of the large vehicle 50 on, for example, an uphill road, the prediction unit 22 can reduce driver discomfort and the forward visibility is poor. This makes it possible for the driver to avoid the situation.

  In FIG. 7, the prediction unit 22 predicts the situation based on the acceleration performance of the normal vehicle that is the host vehicle C and the large vehicle 50. However, the present invention is not limited to this. The situation may be predicted based on performance.

  Next, the process procedure which the control part 2 of the lane change assistance apparatus 1 which concerns on embodiment performs using FIGS. 8-10 is demonstrated. FIG. 8 is a flowchart illustrating a processing procedure executed by the control unit 2 of the lane change support device 1 according to the embodiment.

  As illustrated in FIG. 8, the control unit 2 determines whether there is a space S in the adjacent lane by searching for a space S that is a candidate for the lane change destination of the host vehicle C (step S <b> 101). When it determines with the space S existing (step S101, Yes), the control part 2 performs the prediction process of the condition when the own vehicle C changes the lane to the space S based on the condition around the space S ( Step S102).

  A specific processing procedure of the above-described prediction process will be described later with reference to FIGS. 9 and 10. Moreover, when it determines with the control part 2 not having the space S (step S101, No), a process is complete | finished.

  Subsequently, the control unit 2 determines whether or not the space S is appropriate as a lane change destination based on the predicted situation (step S103). When determining that the space S is appropriate (Yes at Step S103), the control unit 2 determines whether there are a plurality of spaces S to be searched (Step S104).

  When determining that the number is plural (step S104, Yes), the control unit 2 determines the priority to be provided to the driver as a lane change destination for each space S based on the predicted situation (step S105). .

  Subsequently, the control unit 2 performs driving support based on the predicted situation (step S106), and ends the process. On the other hand, when the control unit 2 determines that the number of the spaces S is not plural, that is, the number of the spaces S is one (step S104, No), the process proceeds to step S106.

  On the other hand, when determining that the space S is not appropriate (No at Step S103), the control unit 2 determines whether another space S exists (Step S107).

  When it determines with the other space S existing (step S107, Yes), the control part 2 returns a process to step S102, ie, reexamines the other space S. FIG.

  On the other hand, when it determines with the other space S not existing (step S107, No), the control part 2 transfers a process to step S104.

  Next, a processing procedure for predicting a situation behind the host vehicle by the control unit 2 will be described with reference to FIG. FIG. 9 is a flowchart (part 1) illustrating a processing procedure of prediction processing executed by the control unit 2 according to the embodiment.

  As shown in FIG. 9, when the own vehicle C changes lanes to the space S, the control unit 2 determines whether there is another vehicle behind the space S (step S201). When it determines with the other vehicle existing behind (step S201, Yes), the control part 2 determines whether an other vehicle approaches the space S (step S202).

  When it determines with the other vehicle approaching (step S202, Yes), the control part 2 discriminate | determines the deceleration performance of this other vehicle (step S203). Subsequently, the control unit 2 calculates the reach distance until the relative speed V becomes zero by calculating the distance t until the relative speed V becomes zero, based on the deceleration performance of the other vehicle (step). S204).

  Subsequently, the control unit 2 predicts the situation based on the reach distance (step S205) and ends the process. On the other hand, when it determines with the other vehicle not existing behind, the control part 2 transfers a process to step S205.

  Moreover, when it determines with the control part 2 not approaching another vehicle (step S202, No), a process is transfered to step S205.

  Next, a processing procedure for predicting a situation ahead of the host vehicle by the control unit 2 will be described with reference to FIG. FIG. 10 is a flowchart (part 2) illustrating a processing procedure of a prediction process executed by the control unit 2 according to the embodiment.

  As shown in FIG. 10, when the own vehicle C changes lanes to the space S, the control unit 2 determines whether there is another vehicle ahead of the space S (step S301). When it determines with the other vehicle existing ahead (step S301, Yes), the control part 2 determines whether the own vehicle C approaches another vehicle (step S302).

  When it determines with approaching another vehicle (step S302, Yes), the control part 2 discriminate | determines the acceleration performance of another vehicle (step S303). Subsequently, the control unit 2 calculates the time required for the other vehicle to reach zero relative speed based on the acceleration performance (step S304).

  Subsequently, the control unit 2 determines whether or not another vehicle can be overtaken based on the calculated time (step S305). When it determines with the control part 2 being able to pass (step S305, Yes), a condition is estimated (step S306) and a process is complete | finished.

  On the other hand, when it determines with the other vehicle not existing ahead (step S301, No), the control part 2 transfers a process to step S306. Moreover, when it determines with the other vehicle not approaching (step S302, No), the control part 2 determines whether the other vehicle ahead of the own vehicle is more than predetermined size (step S307).

  When it determines with the other vehicle ahead of the own vehicle being a predetermined size or more (step S307, Yes), the control part 2 discriminate | determines the visibility state ahead of the own vehicle (step S308). On the other hand, the control part 2 transfers a process to step S306, when the other vehicle ahead of the own vehicle is less than predetermined size (step S307, No).

  Moreover, when it determines with the control part 2 not being able to overtake another vehicle (step S305, No), it transfers a process to step S307.

  As described above, the lane change support device 1 according to the embodiment includes the search unit 21, the prediction unit 22, the determination unit 23, and the support unit 25. The search unit 21 searches for a space S that is a candidate for a lane change destination of the host vehicle C. The prediction unit 22 predicts the situation of the host vehicle C when the host vehicle C changes the lane to the space S based on the situation around the space S searched by the search unit 21. The determination unit 23 determines whether the space S is appropriate as a lane change destination based on the situation predicted by the prediction unit 22. The support unit 25 performs driving support according to the determination result of the determination unit 23. Thereby, lane change can be supported without impairing the driver's comfort.

  In the above-described embodiment, the situation in which the vehicle travels on a two-lane road is predicted. However, the present invention is not limited to this, and may be a road having three or more lanes. For example, in the case of a three-lane road, when the host vehicle C travels in the end lane, the search unit 21 searches for the space S that is a candidate for the lane change destination from the other two lanes. In addition, when the host vehicle C travels in the middle lane, the search unit 21 searches for a space S that is a candidate for a lane change destination from adjacent lanes on both sides.

  And the prediction part 22, the determination part 23, and the assistance part 25 support the lane change of the own vehicle C by performing the process similar to above-described embodiment with respect to the space S searched by the search part 21. FIG. .

  Further effects and modifications can be easily derived by those skilled in the art. Thus, the broader aspects of the present invention are not limited to the specific details and representative embodiments shown and described above. Accordingly, various modifications can be made without departing from the spirit or scope of the general inventive concept as defined by the appended claims and their equivalents.

DESCRIPTION OF SYMBOLS 1 Lane change assistance apparatus 2 Control part 3 Memory | storage part 11 Direction indicator 12 Radar apparatus 13 Camera 14 Navigation apparatus 15 Inter-vehicle communication apparatus 16 Vehicle-mounted sensor 17 Output device 21 Search part 22 Prediction part 23 Determination part 24 Order determination part 25 Support part 31 Setting information 50 Large vehicle 51 Normal vehicle 100 Traffic light C Own vehicle S, S1 to S5 Space

Claims (8)

A search unit for searching for a candidate space for a lane change destination of the own vehicle;
A prediction unit that predicts the situation of the host vehicle when the host vehicle changes lanes to the space based on the situation around the space searched by the search unit;
A determination unit that determines whether the space is appropriate as a lane change destination based on the situation predicted by the prediction unit;
A lane change assisting device comprising: a support unit that supports driving according to a determination result of the determination unit. The prediction unit
The lane change according to claim 1, wherein, based on a size of another vehicle traveling in front of the space, a situation of a field of view in front of the own vehicle when the own vehicle changes lanes to the space is predicted. Support device. The prediction unit
The situation behind the host vehicle when the host vehicle changes lanes to the space is predicted based on the deceleration performance of another vehicle that travels behind the space. Lane change support device. The prediction unit
The situation in front of the host vehicle when the host vehicle changes lanes to the space is predicted based on acceleration performance of another vehicle traveling in front of the space. Lane change support device described in one. The support unit
The lane according to any one of claims 1 to 4, wherein when the determination unit determines that the space is appropriate as a lane change destination, the lane change of the host vehicle is assisted. Change support device. The support unit
When the determination unit determines that the space is not appropriate as a lane change destination, at least one of alerting the lane change to the space and reexamining the lane change destination is performed. Item 6. A lane change support device according to any one of Items 1 to 5. The order for determining the priority to be provided to the driver as a lane change destination for each space based on the situation predicted by the prediction unit when there are a plurality of spaces searched by the search unit. A decision unit;
The support unit
The lane change support device according to any one of claims 1 to 6, wherein the support is performed based on the priority order determined by the order determination unit. A search process for searching for a candidate space for a lane change destination of the host vehicle;
A predicting step of predicting a situation of the host vehicle when the host vehicle changes lanes to the space based on a situation around the space searched by the searching step;
A determination step of determining whether the space is appropriate as a lane change destination based on the situation predicted by the prediction step;
A lane change support method, comprising: a support step of supporting driving according to the determination result of the determination step.

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