JP2020020638A - Recommended lane determination device - Google Patents

Abstract

To provide a technique which allows an automatic operation to be continued even when such a sudden event occurs that makes it difficult for a vehicle to run on a recommended lane.SOLUTION: The recommended lane determination device according to the present invention sets the priority of a candidate of a recommended lane according to the number and the difficulty of changing lanes which has to be done for the vehicle to reach the destination of a travel scheduled route, and outputs the priority.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a recommended lane determination device that recommends a lane on which a vehicle travels.

  Currently, technologies for automatically driving vehicles are being actively developed. In automatic driving, it is important to determine the current position of the vehicle. In general, the current position of the vehicle can be determined, for example, by specifying the current coordinates of the vehicle by GNSS (Global Navigation Satellite System) and by specifying the direction of the vehicle by a sensor.

  The driver sets a destination in, for example, a car navigation system, and the car navigation system outputs a route that can reach the destination as a scheduled travel route. The automatic driving control device controls the vehicle such that the vehicle automatically travels on the planned traveling route. At this time, it is necessary to determine which lane of the road the vehicle should travel by comparing the current position of the vehicle with the planned travel route.

  Patent Literature 1 below describes a technique for recommending a lane on which a vehicle travels. This document states, "The route from the current location to the destination is always guided on one optimal recommended lane. Using the lane information acquired by the lane information acquisition unit 7 and the rules read out from the lane calculation rule storage unit 8 in the direction from the target point set by the target point extraction unit 5 toward the current location. The lane determination unit 9 that determines one recommended lane by performing a running lane calculation, and an output unit 10 that guides the determined recommended lane along a trajectory that the lane determination unit 9 runs backwards. ] (See abstract).

JP 2011-226962 A

  In the related art as in Patent Document 1, it is general to recommend a lane that is most suitable for a vehicle to travel. However, in this case, if the vehicle cannot run on the optimal recommended lane for some reason, there is no recommended lane, and it is difficult to continue the automatic driving.

  The present invention has been made in view of the above-described problem, and it is possible to continue automatic driving even when a sudden event occurs such that a vehicle cannot travel on a recommended lane. It aims to provide technology.

  The recommended lane determination device according to the present invention sets the priority of a recommended lane candidate according to the number of lane changes and the lane change difficulty required for the vehicle to reach the destination of the scheduled traveling route, and sets the priority of the recommended lane candidate. Is output.

  According to the recommended lane determination device according to the present invention, even when a sudden event occurs such that the vehicle cannot travel on the recommended lane, the automatic driving control device should take measures to avoid the event. Can be. Thereby, even when such an event occurs, the automatic operation can be continued.

1 is a configuration diagram of a recommended lane determination device 100 according to a first embodiment. This is an example in which priorities are assigned to recommended lane candidates. FIG. 7 is a diagram illustrating a procedure in which a lane recommendation unit sets a priority of a recommended lane. FIG. 9 is a diagram illustrating a procedure in which a recommended lane determination device sets a recommended lane and its priority in a second embodiment. FIG. 13 is a diagram illustrating a procedure in which a recommended lane determination device sets a recommended lane and its priority in a third embodiment. FIG. 14 is a diagram illustrating a procedure in which a recommended lane determination device sets a recommended lane and its priority in a fourth embodiment. It is a figure explaining the procedure which sets a priority considering the lane change frequency and the lane change difficulty.

<First Embodiment>
FIG. 1 is a configuration diagram of a recommended lane determination device 100 according to the first embodiment of the present invention. The recommended lane determination device 100 is a device that determines a lane for which the vehicle is recommended to run, and is configured as an ECU (Electronic Control Unit) mounted on the vehicle. The recommended lane determination device 100 includes a position acquisition unit 110, a route acquisition unit 120, a map acquisition unit 130, and a lane recommendation unit 140.

  The position acquisition unit 110 acquires coordinates representing the current position of the vehicle. The current position of the vehicle can be determined, for example, by specifying the current coordinates of the vehicle using GNSS (Global Navigation Satellite System) and specifying the direction of the vehicle using a sensor. The position acquisition unit 110 may determine the current position of the vehicle by itself, or may receive data representing the current position of the vehicle from outside the recommended lane determination device 100.

  The route acquisition unit 120 acquires data describing a planned traveling route on which the vehicle is to travel. For example, a scheduled travel route can be received from a car navigation system mounted on the vehicle.

  The map acquisition unit 130 acquires map data describing road coordinates from the high-precision map 200 mounted on the vehicle. The high-accuracy map 200 is map information having higher positional accuracy than the vehicle position acquired by the GNSS tuner.

  The lane recommending unit 140 outputs recommended lane candidates for recommending that the vehicle travels according to a procedure described later, calculates the priority of each recommended lane, and outputs them as a pair. The priority here is information indicating how desirable it is for the vehicle to travel in order to reach the destination of the planned traveling route.

  FIG. 2 is an example in which priorities are assigned to recommended lane candidates. It is assumed that the planned traveling route is given as shown in the left diagram of FIG. 2 and that the actual road is configured as shown in the right diagram of FIG. The destination of the scheduled traveling route is located ahead of the branch road. In order to reach the destination, it is desirable that the vehicle travels toward the branch road, so that the lane heading to the branch road has a high priority. The priority decreases as the distance from the branch road increases. If the destination cannot be reached after the fork, the lane after the fork is set to the lowest priority. Whether the vehicle can reach the destination can be determined based on, for example, whether the vehicle can reach the destination within a predetermined distance of travel.

  FIG. 3 is a diagram illustrating a procedure in which the lane recommendation unit 140 sets the priority of the recommended lane. Here, it is assumed that the vehicle is traveling on a road as shown in the right diagram of FIG. The high-accuracy map 200 describes the lanes by the link connection relation. It is assumed that the road in the right diagram in FIG. 2 is described as in the left diagram in FIG. 3, and that the vehicle is heading for the destination at the end of the branch road.

  The route acquisition unit 120 acquires a scheduled traveling route. The scheduled travel route describes a route from the current position of the vehicle to the destination. The travel route does not necessarily describe only the shortest route (hereinafter, referred to as a main path), but also describes a branch route branching from the shortest route (hereinafter, referred to as a subpath). May be. Therefore, as shown in the left diagram of FIG. 3, for example, a lane that cannot reach the destination may be included in the planned traveling route. The lane recommendation unit 140 determines a recommended lane from the set of the main path and the sub path.

  First, the lane recommending unit 140 initializes the priorities of all lanes included in the scheduled travel route from the current position of the vehicle to the destination (step (1)). For example, all the lanes are set to the priority “low”.

  The lane recommendation unit 140 sets the priority of the lane that cannot reach the destination to the lowest priority (step (2)). In FIG. 3, the priority is “×”. The criterion for determining whether or not the destination can be reached is as described above.

  The lane recommendation unit 140 sets the priority of the lane directly connected to the destination to the highest priority (step (3)). In FIG. 3, the priority is set to “high”. Here, "directly connected" means that the lane itself is connected to the destination without passing through another lane. The same applies to the following.

  The lane recommending unit 140 sets the highest priority to the lane directly connected to the lane whose priority is set highest in the immediately preceding step (step (4)). The lane recommending unit 140 repeatedly performs step (4) until the vehicle reaches the current position of the vehicle. Through the above procedure, the recommended lane candidates and the priority of each candidate are set as shown in the right diagram of FIG. 2 and the right diagram of FIG. The lane recommendation unit 140 outputs a recommended lane and its priority. For example, the lane ID described by the high-accuracy map 200 and the priority may be output as a pair.

<Embodiment 1: Summary>
The recommended lane determination device 100 according to the first embodiment outputs a plurality of recommended lane candidates and also outputs the priority of each candidate. As a result, the device (for example, the automatic driving control device) that has received the recommended lane selects the one with the higher priority from the other recommended lanes even if any of the recommended lanes is disabled. be able to. Thus, even when a sudden event occurs such that the vehicle cannot travel on the recommended lane, the event can be avoided.

  The recommended lane determination device 100 according to the first embodiment sets the lane passing from the lane directly connected to the destination to the own vehicle retroactively to the highest priority. Thus, a lane that can efficiently reach the destination can be recommended, and other lanes can also be recommended as candidates.

<Embodiment 2>
In the first embodiment, by following the connection of the lane from the destination to the current position of the vehicle, the recommended lane with the highest priority is set, and the other lanes are set to the priority “low” or “x”. did. In the second embodiment of the present invention, another method for setting the priority “low” will be described. The configuration of the recommended lane determination device 100 is the same as that of the first embodiment.

  FIG. 4 is a diagram illustrating a procedure in which the recommended lane determination device 100 sets a recommended lane and its priority in the second embodiment. In FIG. 4, the current position of the vehicle is a point A, and lanes are branched at points C and D, respectively. In the section from the point A to the point B, the vehicle can travel on one of the two lanes. In the section from point B to point C, the vehicle can travel on any of the three lanes. When passing through the point C, the vehicle will select either to run on the left branch lane or to run on the right two lanes. When passing through point D, the vehicle will choose to run either on the left branch lane or on the right lane. The above relationship is shown by the oval mark in FIG.

  In FIG. 4, the lane recommending unit 140 sets the priority “high” from the destination to the current position of the vehicle in the same manner as in the first embodiment. Here, it is assumed that the priority becomes “high” in order from the upper left lane as shown in FIG. Further, the lane recommending unit 140 sets the priority of the lane that cannot reach the destination to “x” by the same method as in the first embodiment. Here, it is assumed that the first branch lane and the upper right end lane have the priority "x" as shown in FIG.

  The lane recommendation unit 140 determines that if there is a lane that can run in parallel with the lane of the priority “high” and that the vehicle can move (that is, there is no restriction such as lane change prohibition), The priority decreases as the distance from the lane increases. In FIG. 4, the priority of the lanes adjacent to the left and right of the priority “high” is set to “low”. If there are more parallel running lanes to the left and right of the priority "low", that lane may also be set to "low" or a priority lower than "low" (but higher than "x") May be set. That is, the lane recommending unit 140 sets the priority lower as the distance from the lane with the highest priority is increased in the left-right direction. In addition, if the left and right lanes of the priority “high” can be regarded as substantially the same as the “high” from the viewpoint of the traveling route (for example, when the lanes are dense). , The priority may be “high”.

  When the vehicle enters the first branch lane, the vehicle cannot reach the destination, and the vehicle must move to the right two lanes before reaching the first branch lane. Similarly, when the vehicle reaches the upper right end lane, the vehicle cannot reach the target, so the vehicle needs to move to the central lane before reaching the upper right end lane. Therefore, the lane recommendation unit 140 outputs the distance from the current position of the vehicle to the branch point in addition to the priority of each lane. This distance can be calculated by comparing the current position of the vehicle with the coordinates of the branch point on the high-precision map 200. In FIG. 4, the distance between the points AB, the distance between the points AC, and the distance between the points AD are calculated.

  In FIG. 4, the distance between the points AC is important for the vehicle because the vehicle cannot reach the destination when the vehicle goes to the branch lane at the point C. Similarly, if the vehicle moves to the upper right end lane at the point D, the vehicle cannot reach the destination, so the distance between the points AD is important for the vehicle. At point B, the destination can be reached regardless of which lane is traveled, so the distance between points AB is not so important for the vehicle. Therefore, the lane recommendation unit 140 outputs information indicating that, in addition to the distance to each branch point, for a branch point including a branch lane in which the vehicle cannot reach the destination due to the lane change. Here, information indicating that fact is output together with the distance between the points AC, and information indicating that fact is output together with the distance between the points AD.

  The automatic operation control device that has received the distance to the branch point can determine when to shift to the high priority lane. In other words, it is not always necessary to travel on the high priority lane until the vehicle reaches the branch point. Therefore, the automatic driving control device can more freely select the lane in which the vehicle travels from the recommended lane candidates, so that there is a merit that the stability of automatic driving against an unexpected event increases.

<Embodiment 3>
In the second embodiment, the distance from the current position of the vehicle to the branch point is output because the vehicle may not reach the destination when traveling to the branch lane. A similar event may occur in a section where lane change is prohibited. Therefore, in a third embodiment of the present invention, priority assignment when a lane change restriction line exists will be described. The configuration of the recommended lane determination device 100 is the same as that of the first embodiment.

  FIG. 5 is a diagram illustrating a procedure in which the recommended lane determination device 100 sets a recommended lane and its priority in the third embodiment. In FIG. 5, since the vehicle can reach the destination in the branch lane, the lane recommending unit 140 sequentially sets the priority “high” from the branch lane toward the vehicle current position, as in the first embodiment. Since the vehicle cannot reach the destination if the vehicle travels straight through the fork, the lane recommending unit 140 sets the priority of the upper center lane to “x” as in the first embodiment. The priority “low” can be set according to any of the methods of the first and second embodiments.

  When the vehicle passes the lane change regulation line and proceeds to the rightmost lane, the vehicle cannot reach the destination. Therefore, the lane recommending unit 140 sets the priority “x” for the rightmost lane after the start point of the lane change regulation line. Since the lane change regulation line can be handled in the same way as the branch point from the viewpoint of the lane structure, the procedure for setting the priority “x” is the same as in the first and second embodiments.

  The distance from the current position of the vehicle to the start of the lane change regulation line is as important to the vehicle as the distance to the branch point. Therefore, the lane recommending unit 140 calculates the distance from the current vehicle position to the start point of the lane change regulation line (the distance between the points AB), and outputs the calculated distance along with the priority of each lane. Further, if it is impossible to reach the destination after passing through the starting point, information indicating that is output together with the distance. Thereby, even when the lane change regulation line exists, there is a merit that the stability of automatic driving is increased as in the second embodiment. The coordinates of the regulation line may be obtained from the high-precision map 200.

<Embodiment 4>
In the above embodiment, an example in which the priority “high” is set retroactively from the destination to the current position of the vehicle has been described. When this procedure is used, a lane to which the vehicle can shift to the destination lane is set to, for example, priority "low", and a lane to which the vehicle cannot shift to the destination lane is set. For example, the priority “x” is set. However, even if the lane is set to the priority "x", it may be possible to reach the destination by merging with a lane that can reach the destination at a further point. Therefore, in a fourth embodiment of the present invention, a procedure for re-adjusting the once set priority from the viewpoint of whether or not the destination can be reached will be described. The configuration of the recommended lane determination device 100 is the same as that of the first embodiment.

  FIG. 6 is a diagram illustrating a procedure in which the recommended lane determination device 100 sets a recommended lane and its priority in the fourth embodiment. For example, when the recommended lane candidate and the priority are obtained by the procedure described in the first to third embodiments when the vehicle is traveling on the left end lane, the left end lane and the left branch lane are assigned the priority “high” as shown in FIG. , And the priority may be “x” after the right branch lane. However, in FIG. 6, since the right branch lane merges with the left branch lane at a point ahead, it is not always necessary to set the priority to “x”. Therefore, the lane recommendation unit 140 sets the priority of the recommended lane candidate once, and then corrects the priority of the lane that can reach the destination upward. In FIG. 6, the priority after entering the right branch lane is corrected upward from “x” to “low”. The degree of upward correction can be determined as appropriate according to, for example, the number of lane changes and the difficulty level of lane changes described below.

  FIG. 7 is a diagram illustrating a procedure for setting the priority in consideration of the number of lane changes and the difficulty level of the lane change. In FIG. 7, in addition to the lane structure of FIG. 6, a lane change control line is added at the center. The other lane structures are the same as in FIG. The lane recommendation unit 140 sets the priority of the left end lane once to “high” as in FIG. 6, and sets the other lanes in the same manner as in FIG.

  In order to shift from the current vehicle position in FIG. 7 to the leftmost lane, it is necessary to change lanes three times. In the automatic driving, every time the lane is changed, for example, it is necessary to carry out a process such as maintaining an inter-vehicle distance with a vehicle behind, so that the calculation load and the difficulty of the algorithm increase. Therefore, from the viewpoint of automatic driving, it is desirable that the number of lane changes is small.

  In order to shift from the current vehicle position in FIG. 7 to the left end lane, it is necessary to change lanes in a section where no lane change restriction line exists. Therefore, the vehicle needs to execute the lane change at least twice in one section where the priority “low” is set in the center of FIG. 7. That is, since the lane change is performed a plurality of times in a short time, the timing of the lane change is limited, and the difficulty of the lane change is high.

  The lane recommending unit 140 can readjust the priority once set in consideration of the number of lane changes and the difficulty level of the lane change as described above. In FIG. 7, since both the rightmost lane and the leftmost lane can reach the destination, the priority of the lane with the smallest number of lane change times and the lowest lane change difficulty level is corrected upward. For example, (a) the priority of the right end lane and the priority of the left end lane are exchanged, and (b) the priority of the right end lane is made highest, and the priorities of the other lanes are sequentially reduced.

  In the example of FIG. 7, the priority is once set in accordance with the procedure described in the first to third embodiments, and then the priority is readjusted. The priority can also be determined based on. For example, among the lanes that can reach the destination, the lane with the smallest number of lane changes or the lane change difficulty is set to the priority “high”, and the number of lane changes and the lane change difficulty from the lane with the priority “high” are It is conceivable to lower the priority as it increases.

  The lane change difficulty level can be calculated as a numerical value in consideration of various factors. In general, it can be said that the stricter the constraint conditions when changing lanes, the higher the difficulty of changing lanes. In addition to the lane change timing restriction, it is conceivable to consider factors such as speed limit / inter-vehicle distance / congestion / visibility. The lane change difficulty can be quantified by an appropriate method such as weighted addition of these elements.

<Regarding Modification of the Present Invention>
The present invention is not limited to the above embodiments, and includes various modifications. For example, the above embodiment has been described in detail for easy understanding of the present invention, and is not necessarily limited to one having all the described configurations. Further, a part of the configuration of one embodiment can be replaced with the configuration of another embodiment, and the configuration of one embodiment can be added to the configuration of another embodiment. Further, for a part of the configuration of each embodiment, it is possible to add, delete, or replace another configuration.

  In the above-described embodiment, three levels of “high”, “low”, and “x” are illustrated as the priorities, but two-level priorities or four or more levels of priorities may be set. The lowest priority does not necessarily prohibit the vehicle from running.

  Each of the above-described configurations, functions, processing units, processing means, and the like may be partially or entirely realized by hardware, for example, by designing an integrated circuit. Further, each of the above configurations, functions, and the like may be implemented by software by a processor interpreting and executing a program that implements each function. Information such as a program, a table, and a file for realizing each function can be stored in a memory, a hard disk, a recording device such as an SSD (Solid State Drive), or a recording medium such as an IC card or an SD card. In addition, control lines and information lines are shown as necessary for the description, and do not necessarily indicate all control lines and information lines on a product. In fact, it can be considered that almost all components are connected to each other.

100: Recommended lane determination device 110: Position acquisition unit 120: Route acquisition unit 130: Map acquisition unit 140: Lane recommendation unit 200: High-accuracy map

Claims (9)

A recommended lane determination device that recommends a lane in which the vehicle travels,
A position estimating unit that estimates a current position of the vehicle,
A route information obtaining unit that obtains route information describing a scheduled travel route in which the vehicle is scheduled to travel from the current position to the destination;
A map data acquisition unit that acquires map data describing the coordinates of the lane of the road including the planned traveling route,
A lane recommendation unit that determines a recommended lane that recommends that the vehicle travels among the lanes,
With
The lane recommending unit counts the number of lane changes required for the vehicle to reach the destination of the scheduled travel route, and calculates a difficulty coefficient representing the difficulty of the lane change,
The recommended lane determination device, wherein the lane recommending unit sets a priority of the candidate according to the lane change count and the difficulty coefficient and outputs the priority. The lane recommendation unit outputs a plurality of candidates for the recommended lane, and sets a priority indicating a degree of recommending that the vehicle runs the candidate for each candidate, and outputs the priority. The recommended lane determination device according to claim 1, wherein: The recommended lane determination device according to claim 2, wherein the lane recommending unit sets the recommended lane candidates and the priority of the candidates in the order of the lanes that are farthest from the current position of the vehicle. The lane recommendation unit sets the highest priority of the lane directly connected to the destination of the scheduled travel route,
The lane recommendation unit sets the highest priority of each of the lanes that pass by following the connection of the lanes from the lane with the highest priority set to the current position of the vehicle. 3. The recommended lane determination device according to 3. The lane recommendation unit runs in parallel with the lane set with the highest priority, and, for the lanes to which the vehicle can move, sets the priority in order from the closest to the lane set with the highest priority. The recommended lane judging device according to claim 4, wherein the setting is set high. The lane recommendation unit obtains a first distance between a branch point where the lane branches and a current position of the vehicle,
The lane recommendation unit determines whether or not the vehicle can reach the destination of the planned traveling route even if the vehicle shifts to a branch lane at the branch point,
The said lane recommendation part outputs the said 1st distance and the determination result of whether or not the said destination can be reached, together with the said recommended lane candidate and the priority of the said candidate. Recommended lane determination device described. The lane recommendation unit acquires a start point of a section where lane change is prohibited from the map data,
If the vehicle cannot reach the destination of the scheduled traveling route when the vehicle reaches the start point, the lane recommending unit sets the priority of the lane after the start point lower than other lanes. The recommended lane determination device according to claim 2, wherein: The lane recommendation unit acquires a second distance between a start point of a section where lane change is prohibited and a current position of the vehicle from the map data,
The recommended lane determination device according to claim 2, wherein the lane recommending unit outputs the second distance together with the recommended lane candidate and the priority of the candidate. The lane recommendation unit sets the priority of the reachable lane in a case where there is a reachable lane in which the vehicle can reach the destination of the scheduled travel route, other than the lane set with the highest priority. The recommended lane determination device according to claim 2, wherein the correction is performed upward.

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