Method for determining a navigation route for a vehicle, computer program, navigation system and vehicle

Abstract

The invention relates to a method for determining a navigation route for a vehicle, wherein a point of interest (POI) located off a road (2) is specified as the navigation destination (1), and the navigation route leads to an access point (3) located on a road (2) and associated with the point of interest (POI). The invention is characterized by the following method steps: A: Calculating a standard navigation route from the vehicle's location to the point of interest (POI) based on a standard map; B: Providing an alternative navigation route to the point of interest (POI); C: Determine a distance between the last navigation point on the road (2) and the point of interest (POI) in the form of a standard distance for the standard navigation route and an alternative distance for the alternative navigation route; D: Calculate the difference between the standard distance and the alternative distance and check whether the amount of the difference is greater than a specified first distance threshold, where if this is the case: E: Setting the last navigation point on the road (2) of the alternative navigation route as the new destination for the standard navigation route and Recalculating the default navigation route; F: Recalculating the standard distance; G: Comparing the standard distance with a specified second distance threshold; and H1: If the recalculated standard distance is less than the set second distance threshold: Use the standard navigation route to guide the vehicle to the destination.

Description

[0001] The invention relates to a method for determining a navigation route for a vehicle according to the type defined in more detail in the preamble of claim 1, as well as a computer program, a navigation system and a vehicle for carrying out the method.

[0002] With the help of a navigation system, users can find their way even in unfamiliar regions. To determine their current location, navigation systems can include a receiver for satellite signals transmitted by global navigation satellites. These include systems such as GPS, Galileo, and similar technologies. By comparing the determined geolocation with a digital road map, the currently traveled road segment can be identified. After entering the destination, a navigation route from the current location to the destination can be calculated and displayed to the user.

[0003] A frequently used category for destinations is the so-called Point of Interest (POI). This includes places like supermarkets, swimming pools, parking garages, gas stations, doctors' offices, hospitals, restaurants, cafes, parks, tourist attractions, and the like. Due to its size, a Point of Interest typically occupies an area on the digital map. This requires storing information on the digital map indicating the access points to the area from a given street. Only if these access points are correctly specified can a navigation route, for example, end correctly at the entrance to a parking garage and not at the back of the garage. Such a situation negatively impacts the user experience, as the user then has to search for the entrance themselves.It may even be necessary to take detours to reach the correct access point.

[0004] Conventional navigation systems use nearest-map matching to guide vehicles to a point of interest. However, if the underlying map data is inaccurate or lacks sufficient detail, this can lead to a correspondingly inaccurate navigation route. To ensure, for example, that a user is directed to a parking area next to a highway and not onto the highway itself, these access points can be specified as so-called entry points, also known as reference points. Reference points enable appropriate navigation guidance up to the end of the mapped area, thus ensuring the user can continue driving into the unmapped area. If these reference points are missing or incorrectly placed, navigation becomes more difficult for the user.

[0005] German patent DE 10 2017 209 529 A1 discloses a driver assistance system for a motor vehicle and a method for approaching a parking space with a charging station. A control unit evaluates sensor data acquired when approaching the parking space to determine historical approach routes. Based on this, an averaged approach trajectory is calculated and used for future approaches to the parking space. The vehicle can be controlled manually or automatically. The averaged approach trajectory can also be used in other vehicles that were not involved in recording the historical approach routes. The sensor data can include odometry data, enabling navigation to continue even if the satellite navigation connection is interrupted.

[0006] Furthermore, US patent 2020 / 0363225 A1 discloses a method and a device for identifying an offset of a point of interest. The offset is detected by identifying an inconsistency between a route-guiding attribute in a map and an updated map.

[0007] Furthermore, JP 2010-237158A discloses a method and system for navigating a vehicle. This involves identifying points of interest near destinations of past journeys undertaken by the vehicle. Starting from each point of interest, the route is traced back until a change in the underlying road type is detected. The corresponding transition point is defined as the access point to the point of interest, and the remaining route from the access point to the point of interest is defined as the access route for journeys that terminated at the point of interest. The segment from the access point via the access route to the point of interest is used for future route queries.

[0008] Furthermore, US patent 2018 / 0087922 A1 discloses a method for discovering access points to locations. This method identifies journeys from historical trips that end at a point of interest. The point of interest is associated with a building. A walking route is determined from the parking location of the vehicle used for the trip to the building. The point where the walking route ends at the edge of the building is defined as the access point to the building.

[0009] The present invention is based on the objective of providing an improved method for determining a navigation route for a vehicle, with the help of which an increased user experience can be achieved when navigating to points of interest.

[0010] According to the invention, this problem is solved by a method for determining a navigation route for a vehicle with the features of claim 1. Advantageous embodiments and further developments, as well as a computer program, a navigation system, and a vehicle for carrying out the method, are set forth in the dependent claims.

[0011] A generic method for determining a navigation route for a vehicle, wherein the navigation destination is a point of interest located off a road and the navigation route leads to an access point located on a road and associated with the point of interest, is further developed according to the invention by the following method steps: A: Calculating a standard navigation route from the vehicle's location to the point of interest based on a standard map; B: Providing an alternative navigation route to the point of interest; C: Determining a distance between the last navigation point on the road and the point of interest in the form of a standard distance for the standard navigation route and an alternative distance for the alternative navigation route; D: Calculating the difference between the standard distance and the alternative distance and checking whether the amount of the difference is greater than a specified first distance threshold, where if this is the case: E: Setting the last navigation point on the road of the alternative navigation route as the new destination for the standard navigation route and recalculating the standard navigation route; F: Recalculating the standard distance; G: Comparing the standard distance with a specified second distance threshold; and H1: If the recalculated standard distance is less than the set second distance threshold: Use the standard navigation route to guide the vehicle to the destination.

[0012] The invention is based on the idea of ​​using supplementary map or route data to automatically find suitable access points for a given point of interest. This ensures that the map data not only contains access points for a point of interest, but that these access points also correspond to the actual locations from which the respective point of interest can be reached most efficiently. As soon as a shorter route from a given location to a particular point of interest is possible, this is already perceived as an improvement by the user. Since the navigation guidance is thus implemented more reliably, the user experience is enhanced.

[0013] In step A, the standard navigation route to the point of interest is calculated. For this, the navigation system accesses the designated digital road map. Since this is the standard operating behavior of the navigation system, the calculated navigation route is referred to as the standard navigation route and the digital road map used as the standard map.

[0014] In step B, an alternative navigation route is then provided. Several options are available for providing the alternative navigation route, which will be discussed in more detail below. Because this navigation route is not generated based on the standard behavior of the navigation system, it is referred to as an alternative navigation route.

[0015] Each navigation route represents a chain of waypoints extending from the vehicle's location to the point of interest. The standard navigation route and the alternative navigation route differ in the precise geocoordinates of the individual waypoints. In particular, the last waypoint located on the road differs. From this waypoint, a distance to the point of interest is calculated for both navigation routes in step C, for example, a Euclidean distance. To better distinguish between the two distances, the distance from the last waypoint located on the road in the standard navigation route to the point of interest is referred to as the standard distance, and the distance from the last waypoint located on the road in the alternative navigation route to the point of interest is referred to as the alternative distance.

[0016] If the last two navigation points of the navigation routes are geographically close to each other or even identical, the difference in distances is relatively small. In this case, a more suitable access point to the point of interest for the standard navigation route could not be found based on the alternative navigation route. To verify this, the difference between the standard distance and the alternative distance is compared to the defined first distance threshold. The first distance threshold can be flexibly set by the developers depending on the situation. For example, a uniform, constant value can be chosen for all roads and all points of interest. However, the first distance threshold could also depend on various parameters, such as the type of road on which the last navigation point of the respective navigation route is located, the type of point of interest, and so on.

[0017] If the difference between the standard distance and the alternative distance is large enough, meaning both navigation points are sufficiently far apart, then step E is executed. Otherwise, navigation can proceed as usual, based on the standard navigation route. In step E, however, the last navigation point of the alternative navigation route is set as the new destination or endpoint for the standard navigation route, and the navigation route is recalculated accordingly. Due to the different destination, the recalculated standard navigation route will differ from the initially calculated standard navigation route. If it is assumed that the alternative navigation route is more likely to lead to a suitable access point to the point of interest, then the probability that this also applies to the recalculated standard navigation route increases accordingly.

[0018] Steps F and G now check the proximity of the new end of the standard navigation route to the point of interest. A second, predefined distance threshold serves as a comparison for this purpose. Here, too, the developers can adjust the level of this second distance threshold to suit the specific situation.

[0019] If the newly calculated standard distance is less than the second defined distance threshold, the newly calculated standard navigation route is suitable for output to the user. The vehicle can be controlled manually, semi-automatically, or autonomously along the navigation route. The vehicle is more likely to be guided to a suitable access point to the point of interest, thus improving the user experience.

[0020] An advantageous embodiment of the method according to the invention provides that if, in step G, the standard distance is greater than the second distance threshold (alternative step H2), a defined distance is subtracted from the alternative navigation route, starting from the last navigation point on the road, to determine an alternative endpoint. Steps E to H2 are then repeated using the alternative endpoint as the new destination for the standard navigation route in step E until step H1 can be executed. This ensures that a suitable navigation route can be found. The defined distance traveled backward along the alternative navigation route to find a suitable alternative endpoint can also be determined by the developers depending on the situation. Here, too, a fixed or parameter-dependent value can be chosen.If, based on the alternative endpoint as the new destination for the recalculated standard navigation route, the standard distance is still greater than or equal to the second distance threshold, a new alternative endpoint is determined that lies even further back on the alternative navigation route. This process is executed iteratively until step H1 can be carried out.

[0021] According to a further advantageous embodiment of the method according to the invention, it is further provided that - the alternative navigation route in step B is determined by calculating a navigation route from the vehicle's location to the point of interest based on alternative map data; or - the alternative navigation route in step B is determined based on historical fleet data, wherein the historical fleet data includes the locations of vehicles from past journeys, and a chain of the locations of such a vehicle is used as the alternative navigation route, which performed a parking operation at a specified parking distance to the point of interest.

[0022] It is possible to provide multiple alternative navigation routes, based on alternative chart data and / or historical fleet data, and to use them to transfer the respective last navigation points to the standard navigation route. Steps C to H1 can be performed individually for each alternative navigation route, with one result ultimately selected from the various calculations as the target for the standard navigation route. Alternatively, an averaged route can be created from some or all of the alternative navigation routes and used for steps C to H1.

[0023] The provision of alternative map data and / or fleet data can be handled by a central computing facility, such as a cloud server. The alternative navigation route can also be calculated by the central computing facility itself and transmitted to the vehicle or navigation system.

[0024] As an alternative map data source, a highly detailed and high-resolution map is used. This increases the likelihood of finding suitable access points. A lower-resolution map can be stored in the vehicle's navigation system, thus minimizing the storage space required in the mobile unit.

[0025] If the alternative navigation route is determined based on historical fleet data, a particularly reliable determination of access points is possible. This allows for the assumption that, in the past, the respective vehicles correctly approached the point of interest, thus choosing the most suitable access point. Depending on the point of interest, this could mean parking either directly at the point of interest or at some distance from it. The navigation points of the alternative route are then not based on calculations by an algorithm, but rather on the actual locations of the vehicles that provided the historical fleet data.

[0026] It is conceivable that some of the vehicles that provided the historical fleet data got lost while approaching the point of interest or chose an incorrect access point. Measures can be taken to prevent navigation points from being used by such vehicles. For example, only those vehicle positions that occur particularly frequently in the statistical average can be used. This is based on the assumption that vehicles that got lost represent statistical outliers. Alternatively, only the most recent positions could be used. For instance, due to a learning effect, it can be assumed that people who have already gotten lost will not do so again in the future.

[0027] A further advantageous embodiment of the method according to the invention provides that for vehicles that park within the defined parking distance to the point of interest and whose parking locations differ by a defined amount, the respective parking locations are used as additional access points for the point of interest. Generally, it is conceivable that a point of interest has several suitable access points. According to the invention, these access points can be located and used for route navigation. In specific locations, this can even lead to the determination of navigation routes that differ significantly over a wide area. In this way, suitable route navigation is ensured from the outset, which further improves the user experience.

[0028] According to the invention, a computer program comprises machine-interpretable instructions which, when executed by a processor of a computing unit, cause the unit to execute a method described above. If partial steps of the method, such as calculating the alternative navigation route or providing historical fleet data and / or alternative map material, are outsourced to an external computing facility, such as the aforementioned cloud server, then the computer program is also executed in multiple parts. This allows each part of the underlying information technology system to execute all necessary steps.

[0029] A navigation system according to the invention comprises read access to a computer-readable storage medium containing said computer program. Thus, the method according to the invention can be executed by the navigation system itself. The central computing unit also has read access to a corresponding computer-readable storage medium containing a computer program suitable for the steps to be executed by the cloud server.

[0030] A vehicle according to the invention comprises such a navigation system. The navigation system can be permanently integrated into the vehicle or be connectable to the vehicle. All possible road vehicles such as cars, trucks, vans, buses, or the like are eligible.

[0031] Further advantageous embodiments of the inventive method for determining a navigation route also result from the exemplary embodiments, which are described in more detail below with reference to the figures.

[0032] This shows: Fig. 1 A flowchart of the method according to the invention; and Fig. 2 A schematic representation of different access points to a point of interest in a digital street map.

[0033] To reliably transport the user of a vehicle to a location in Fig. To guide the vehicle to the POI shown in Figure 2, navigation routes to be displayed to the user via a navigation system can be calculated using a method according to the invention. The navigation route leads to an access point 3 to the POI, which allows the vehicle to drive as close as possible to the POI or even into it. This prevents, for example, a navigation route from ending at the back of a furniture store's parking lot instead of at the entrance to the parking lot.

[0034] The procedure is described in Fig. Figure 1 illustrates this process. In step 101, a standard navigation route is calculated from the vehicle's location to the point of interest (POI) based on a standard map. Step 101 corresponds to step A. In the subsequent step 102, a distance is determined between the last navigation point on road 2 of the standard navigation route and the point of interest (POI), for example, the Euclidean distance in the underlying digital road map. Step 102 is a sub-step of step C. This distance is referred to as the standard distance.

[0035] In parallel, steps 103 and 104 are executed. In step 103, corresponding to step B, an alternative navigation route to the point of interest (POI) is determined and provided. This alternative navigation route can extend from the vehicle's current location to the POI if it is calculated using known route calculation algorithms on an alternative digital road map. The alternative digital road map can be transmitted from a central computing unit 4 to the vehicle or the navigation system used in the vehicle, at least for the relevant section. It is also conceivable that the vehicle's current position is transmitted to the central computing unit 4, whereupon the central computing unit 4 calculates the alternative navigation route and transmits it back to the vehicle.

[0036] The alternative navigation route can also be based on historical fleet data. For this purpose, vehicles in a fleet transmit their positions, determined at regular intervals, to the central computing unit 4. As soon as one of the vehicles performs a parking maneuver at a defined distance from the point of interest (POI), the positions of that vehicle are released for the generation of alternative navigation routes. In this case, the alternative navigation route does not necessarily extend from the vehicle's current location to the POI, but rather reflects the route driven by the other vehicle. However, only the last segment of the navigation route is relevant for carrying out the method according to the invention, since this contains the access point to the POI.The chaining of the fleet vehicle's current positions, at least in the vicinity of the point of interest (POI), can then be retrieved from the central computer unit 4 as an alternative navigation route for the vehicle.

[0037] In step 104, corresponding to a sub-step of step C, a distance is now determined between the last navigation point of the alternative navigation route located on road 2 and the point of interest (POI). This distance is referred to as the alternative distance.

[0038] In the subsequent step 105, corresponding to step D, the difference between the standard distance and the alternative distance is calculated and compared to a defined initial distance threshold. The system checks whether this difference is less than or equal to the initial distance threshold. If so, step 106 is executed. Step 106 ensures that no suitable access point to the point of interest (POI) can be calculated other than the one that was already calculated.

[0039] If, however, the amount is greater than the first distance threshold, step 107 is executed, corresponding to step E. In this step, the last navigation point of the alternative navigation route located on road 2 is set as the new destination for the standard navigation route, and the standard navigation route is recalculated in step 108.

[0040] Step 109 is now executed, corresponding to steps F and G. The standard distance is recalculated, and this value is compared to a second, predefined distance threshold. The system checks whether the recalculated standard distance is greater than or equal to the second distance threshold. If so, step 110 is executed. Step 110 corresponds to step H2, which involves repeatedly moving backward from the currently considered last navigation point on road 2 of the alternative navigation route by a defined distance, for example, in increments of 5 meters, and using each considered endpoint as the new destination for the standard navigation route, until the recalculated standard distance is less than the second distance threshold.

[0041] If this is the case, step 111 is executed, corresponding to step H1. The newly calculated navigation route is then used as the default navigation route for destination guidance in the vehicle. The vehicle can be controlled manually, semi-automatically, or autonomously along at least one or a portion of the route.

[0042] Fig. Figure 2 illustrates the positive effect of the method according to the invention. For example, a point of interest (POI) is shown that is comparatively close to one in Fig. 2 upper street 2 and relatively far from one in Fig.The point of interest (POI) is located on the street 2 shown below. Two access points 3 to the POI are shown. The POI is set as a navigation destination 1 in a vehicle's navigation system. The upper access point 3 is separated from the POI by a fence 5, so the POI cannot be reached when parking near the upper access point 3. However, if the lower access point 3 is used, the POI can be easily reached via a path 6, even though the lower access point 3 is farther away than the upper access point 3.

[0043] The implementation of the method according to the invention allows for route guidance to the lower access point 3, which improves the user experience.

Claims

[1] Method for determining a navigation route for a vehicle, wherein the navigation destination (1) is a point of interest (POI) located off a road (2) and the navigation route leads to an access point (3) located on a road (2) associated with the point of interest (POI), characterized by the following procedural steps: A: Calculating a standard navigation route from the vehicle's location to the point of interest (POI) based on a standard map; B: Providing an alternative navigation route to the point of interest (POI); C: Determine a distance between the last navigation point on the road (2) and the point of interest (POI) in the form of a standard distance for the standard navigation route and an alternative distance for the alternative navigation route; D: Calculating the difference between the standard distance and the alternative distance and checking whether the amount of the difference is greater than a specified first distance threshold, where if this is the case: E: Setting the last navigation point on the road (2) of the alternative navigation route as the new destination for the standard navigation route and recalculating the standard navigation route; F: Recalculating the standard distance; G: Comparing the standard distance with a specified second distance threshold; and H1: If the recalculated standard distance is less than the set second distance threshold: Use the standard navigation route to guide the vehicle to the destination. [2] Method according to claim 1, characterized by, that if in step G the standard distance is greater than the second distance threshold as alternative step H2, starting from the last navigation point on the road (2) of the alternative navigation route, a specified distance is subtracted from the alternative navigation route to determine an alternative endpoint, and steps E to H2 are repeated using the alternative endpoint as the new destination for the standard navigation route in step E until step H1 is executable. [3] Method according to claim 1 or 2, characterized by , that - the alternative navigation route in step B is determined by calculating a navigation route from the vehicle's location to the point of interest (POI) based on alternative map data; or - the alternative navigation route in step B is determined based on historical fleet data, wherein the historical fleet data includes the locations of vehicles from past journeys, and a chain of locations of such a vehicle is used as the alternative navigation route, which performed a parking operation at a specified parking distance to the point of interest (POI). [4] Method according to claim 3, characterized by , that for vehicles that performed a parking maneuver to the point of interest (POI) within the specified parking distance and whose parking locations differed by a specified amount, the respective parking locations are used as further access points (3) for the point of interest (POI). [5] Computer program, characterized byMachine-interpretable instructions which, when executed by a processor of a computing unit, cause it to execute a method according to one of claims 1 to 4. [6] Navigation system, characterized by Read access to a computer-readable storage medium comprising a computer program according to claim 5. [7] vehicle, characterized by a navigation system according to claim 6.

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