Navigation device, navigation method, and navigation program

Abstract

To provide a technique which can increase such a possibility that a vehicle can be parked in the vicinity of a destination.SOLUTION: In an embodiment of the present disclosure, first, a navigation device acquires a destination set by a user. Then, the navigation device acquires information about a vacant parking space accessible from a road for each road near the destination. Then, the navigation device selects a road in which the number of vacant parking spaces that are accessible is equal to or greater than a prescribed number as a guide destination to which the vehicle is guided.SELECTED DRAWING: Figure 2

Description

Technical Field

[0004] ,

[0006] , , , , , ,

[0005] , , ,

[0003] , , , , ,

[0001] The present disclosure relates to navigation technology including a navigation device, a navigation method, and a navigation program, and particularly to navigation technology that can be used in autonomous vehicles.

Background Art

[0002] As a conventional technology for the navigation technology of the present disclosure, a parking lot information guidance device disclosed in Japanese Patent Application Laid-Open No. 2020-122722 can be cited. In this conventional technology, when the parking lot attached to the destination is full, the destination is changed to the first parking area. When the parking lot in the first parking area is full, the destination is further changed to the second parking area.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] The above conventional technology merely notifies available parking lots in order. When a parking lot is full and it is necessary to move to another available parking lot, there is no guarantee that they face the same road, and it may take time to move between parking lots. As a result, when the vehicle arrives at the parking lot designated as the destination, it may happen that the parking lot is also full.

[0005] The present disclosure has been made in view of the above problems. An object of the present disclosure is to provide a technology capable of increasing the probability of parking a vehicle near a destination.

Means for Solving the Problems

[0006] To achieve the above objective, this disclosure provides a navigation device. The navigation device of this disclosure comprises at least one processor and at least one memory storing a plurality of instructions that can be executed by the at least one processor. The plurality of instructions are configured to have the at least one processor perform the following processes: The first process is to obtain a set destination. The second process is to obtain information about available parking spaces accessible from the road for each road near the destination. The third process is to select a road in which the number of available parking spaces is greater than or equal to a predetermined number as a destination for guiding the vehicle.

[0007] Furthermore, in order to achieve the above objectives, this disclosure provides a navigation method using a navigation device. The navigation method of this disclosure includes the following steps: The first step is to obtain a set destination. The second step is to obtain information on available parking spaces accessible from the road for each road near the destination. The third step is to select a road in which the number of available parking spaces is equal to or greater than a predetermined number as a destination to guide the vehicle.

[0008] Furthermore, to achieve the above objectives, this disclosure provides a navigation program. The navigation program of this disclosure is configured to cause a navigation device to execute the above navigation method. The navigation program of this disclosure may be recorded on a non-temporary computer-readable recording medium.

[0009] In the navigation technology of this disclosure, roads whose estimated travel time exceeds a predetermined allowable time may be excluded from the guided route. Alternatively, the guided route may be selected as the road closest to the destination among roads with a predetermined number or more available parking spaces. [Effects of the Invention]

[0010] According to the navigation technology disclosed herein, roads near the destination that have a predetermined number or more accessible available parking spaces are selected as the destination, thereby increasing the probability of being able to park the vehicle near the destination. [Brief explanation of the drawing]

[0011] [Figure 1] This is a block diagram showing the configuration of a navigation device according to the first embodiment of this disclosure. [Figure 2] This is a flowchart showing a navigation method according to the first embodiment of this disclosure. [Figure 3] Figure 2 illustrates a specific example of using the navigation method shown in Figure 2 to search for parking in an urban area. [Figure 4] Figure 2 illustrates a specific example of using the navigation method shown in Figure 2 to search for a parking space within a parking lot. [Figure 5] This is a block diagram showing the configuration of an autonomous vehicle equipped with a navigation system according to a second embodiment of this disclosure. [Figure 6] This is a flowchart showing a navigation method according to a second embodiment of the present disclosure. [Modes for carrying out the invention]

[0012] 1. First Embodiment 1-1. Navigation System The navigation system according to the first embodiment is installed in a vehicle that is manually driven by a driver. When the user sets a destination, the navigation system according to the first embodiment is configured not to suggest a route to that destination to the user, but rather to select the most suitable road from among the roads near the destination to find a parking space for the vehicle, and then to suggest guidance to the user along that road. The configuration of the navigation system according to the first embodiment will be described below with reference to Figure 1.

[0013] Figure 1 is a block diagram showing the configuration of a navigation device 2 according to the first embodiment. The navigation device 2 comprises a computing device 10, a storage device 20, a display device 21, an operating device 22, a communication device 23, a vehicle status sensor 24, and a GPS receiver 25. The storage device 20, the display device 21, the operating device 22, the communication device 23, the vehicle status sensor 24, and the GPS receiver 25 are communicated to the computing device 10.

[0014] The storage device 20 is a storage device that stores data necessary for navigation. The stored data includes high-precision map data. The stored data also includes the destination set by the user and the road selection parameters set by the user. The navigation device 2 selects a road to suggest to the user from among several roads near the destination. The road selection parameters are parameters used in the processing of this selection. The storage device 20 stores the following three parameters as road selection parameters. Parameter 1: Road division distance (Explanation) Long roads are divided into sections (2 sections, 3 sections, etc.) until the total length is shorter than the original division distance. Parameter 2: Allowable time difference in required time (Explanation) Compared to the shortest travel time from the current vehicle's location, roads that are farther away and exceed the acceptable travel time difference will be excluded from the list of candidates. Parameter 3: Setting the distance to the destination (Explanation) The distance to the destination of the road used in selecting the proposed road can be set to either the distance from the center of the road or the distance from the centroid of the location of the available parking space.

[0015] The display device 21 and the operating device 22 are HMIs of the navigation device 2. The display device 21 displays a map and can also display various information on the map, such as the vehicle's position, destination, route to the destination, suggested roads, and route to the guided road. The operating device 22 accepts input from the user. User input includes, for example, setting a destination, setting road selection parameters, and selecting a guided road from among several suggested roads.

[0016] The communication device 23 is a device that controls the communication between the navigation device 2 and the external device 40. The communication device 23 communicates with the external device 40 via a communication network. The external device 40 is, for example, a cloud server. Information on the available parking spaces in parking lots pre-registered for the service is collected in real time or at regular intervals in the external device 40. The navigation device 2 acquires information on the available parking spaces for each parking lot from the external device 40 using the communication device 23. The acquired information on the available parking spaces is stored in the storage device 20.

[0017] The vehicle state sensor 24 includes a vehicle speed sensor, an acceleration sensor, and a gyro sensor. The information obtained by these sensors is used, together with the information obtained by the GPS receiver 25, for calculating the position, attitude, and movement direction of the host vehicle on the map.

[0018] The arithmetic unit 10 is the main body of the navigation device 2. The arithmetic unit 10 includes a processor and a memory. The processor includes a CPU 11, and the memory includes a ROM 12 and a RAM 13. The ROM 12 and the RAM 13 are communicably coupled to the CPU 11. The number of each of the CPU 11, the ROM 12, and the RAM 13 constituting the arithmetic unit 10 may be either singular or plural. The ROM 12 stores at least one program executable by the CPU 11. The program stored in the ROM 12 includes a navigation program. The navigation program consists of a plurality of instructions. When these instructions are executed by the CPU 11, the CPU 11 functions as a host vehicle position estimation unit 14, a route search unit 15, a road extraction unit 16, and a road proposal unit 17. The functions of each unit will be described below.

[0019] The vehicle position estimation unit 14 estimates the vehicle's position on the map based on the information acquired by the vehicle condition sensor 24 and the GPS receiver 25. Specifically, the vehicle's coordinates on the map are estimated from the information from the GPS receiver 25. The vehicle's attitude on the map is estimated from the information from the gyro sensor. Then, the amount of movement of the vehicle on the map is estimated from the information from the vehicle speed sensor and the acceleration sensor.

[0020] The route search unit 15 searches for a route from the vehicle's current location to a specified location. The searched route is displayed on the display device 21 as needed. The specified location includes locations specified by the user and locations specified by the CPU 11 itself. Locations specified by the user include destinations set by the user and roads selected by the user as the route to be guided. Locations specified by the CPU 11 itself will be explained in the description of the road extraction unit 16.

[0021] The road extraction unit 16 extracts roads closest to the destination from the map information in order. If the destination is a facility with an entrance, the road extraction unit 16 extracts roads based on that entrance. In this case, roads longer than the division distance set by parameter 1 are divided into multiple roads, and each of the divided roads is extracted as a separate road. The road extraction unit 16 also uses the route search unit 15 to calculate the time required from the vehicle's current position to each road. Then, the road extraction unit 16 excludes roads from extraction if the time required exceeds the allowable time difference, based on the road with the shortest time required.

[0022] The road suggestion unit 17 acquires the location and availability information of parking spaces recorded in the external device 40 via the communication device 23. Then, based on the acquired information, the road suggestion unit 17 aggregates the number of available parking spaces accessible for each road extracted by the road extraction unit 16. The available parking spaces aggregated include not only available parking spaces in parking lots directly facing the road, but also available parking spaces in all parking lots accessible from the road.

[0023] Next, the road suggestion unit 17 suggests a road that is close to the destination (a road close to the entrance of the destination facility) from among roads that have a predetermined number or more accessible available parking spaces. The predetermined number, i.e., the number of available parking spaces that serves as the basis for the suggestion, may be a fixed value or a parameter that can be set by the user. The suggested road that is close to the destination is selected according to the setting of parameter 3, which is the distance to the destination. The road suggestion unit 17 displays the suggested road on the display device 21. When the user selects that road using the operating device 22, the route search unit 15 starts route guidance with that road as the destination.

[0024] 1-2. Navigation Method 1-2-1. Overview Figure 2 is a flowchart of the navigation method (navigation method according to this embodiment) performed by the navigation device 2 described above. The navigation method according to this embodiment comprises eight steps from step S11 to step S18. The outline of each step is as follows. Step S11: Obtain the destination set by the user. Step S12: Determine whether the vehicle has arrived near the destination. Step S13: After the vehicle arrives near the destination, roads near the destination are extracted. Step S14: The availability of parking spaces accessible from the road is tallied, and the tally results are superimposed on the road displayed on the screen of the display device 21. Step S15: Propose the most suitable road to the user from among roads with many accessible parking spaces. Step S16: Determine whether the user has accepted the proposal. Step S17: The user obtains the road they selected themselves after the user did not accept the proposal. Step S18: Modify the route to guide the vehicle to the suggested road or the road selected by the user.

[0025] 1-2-2. Specific Example 1 Next, the details of each step of the navigation method according to this embodiment will be specifically explained using Figure 3. Figure 3 is a diagram illustrating a specific example in which the navigation method according to this embodiment is used to search for parking in an urban area.

[0026] Step S11: The user selects a destination 1001 on the map 100 displayed on the display device 21 using the operating device 22 and sets it to the arithmetic unit 10. The arithmetic unit 10 retrieves the destination 1001 set by the user and stores it in the storage device 20.

[0027] Step S12: The calculation unit 10 compares the position of the vehicle estimated by the vehicle position estimation unit 14 with the destination 1001 and determines whether the vehicle has arrived at a point a predetermined distance from the destination 1001. The predetermined distance, which is the criterion for determining whether the vehicle is near the destination 1001, may be a fixed value such as 500m or 1km, or it may be set arbitrarily by the user.

[0028] Step S13: The road extraction unit 16 of the computing unit 10 first refers to the high-precision map data stored in the storage device 20 and extracts the road 1010 that faces the destination 1001 from among the roads around the destination 1001. Next, the road extraction unit 16 extracts the roads 1011-1016 that have a direct connection relationship with road 1010. The road extraction unit 16 repeats this extraction a predetermined number of times. In the case of a road with separate uphill and downhill lanes, it extracts the roads that have a connection relationship with the uphill and downhill lanes, respectively. Alternatively, one method for extracting roads near the destination 1001 is to extract roads that are within a predetermined radius from the destination 1001.

[0029] Furthermore, the road extraction unit 16 selects roads to be extracted according to parameter 2 of the road selection parameters. In other words, the road extraction unit 16 selects the road with the shortest travel time from the vehicle's current location, and excludes roads that are farther away and whose travel time difference exceeds the allowable time difference from the road's current location. In the example shown in Figure 3, roads 1017-1019 are roads that are far from the vehicle's current location (not shown), and are therefore excluded from extraction despite the existence of parking lots facing these roads.

[0030] Step S14: The calculation unit 10 first aggregates the availability of parking spaces in parking lot 1003 accessible from road 1010 and displays the number of available parking spaces on counter 1020 superimposed on road 1010. Next, the calculation unit 10 calculates the total number of available parking spaces for parking lots 1002, 1004, and 1005 accessible from road 1011 and displays the total number of available parking spaces on counter 1021 superimposed on road 1011. Parking lots 1006 and 1007 are accessible from road 1015. The calculation unit 10 calculates the total number of available parking spaces for parking lots 1006 and 1007 and displays the total number of available parking spaces on counter 1022 superimposed on road 1015. On the other hand, there are no parking lots accessible from roads 1012, 1013, 1014, and 1016. Therefore, nothing is displayed on roads 1012, 1013, 1014, and 1016.

[0031] In addition to displaying the number of available parking spaces, the roads may also be colored according to the number of available spaces. For example, road 1010, which has 0 available parking spaces, may be colored red; road 1015, which has many available spaces, may be colored blue; and road 1011, which has few available spaces, may be colored yellow. Roads 1012, 1013, 1014, and 1016, which do not face a parking lot, may be colored black.

[0032] Step S15: The road suggestion unit 17 of the calculation unit 10 suggests to the user a road that is close to the destination 1001 from among roads with a predetermined number or more accessible available parking spaces. The distance calculation at the time of suggestion is performed according to the setting of parameter 3 of the road selection parameters. In the example shown in Figure 3, only roads 1011 and 1015 have a predetermined number or more accessible available parking spaces. Of these, road 1011 is the road with the shorter distance from the destination 1001, so the road suggestion unit 17 suggests road 1011 to the user. The suggestion is made, for example, by moving the cursor 1030 to the counter 1021 and highlighting road 1011 and parking lots 1002, 1004, and 1005.

[0033] In this example, roads whose travel time from the current vehicle exceeds the acceptable time compared to other roads are excluded from the extraction. However, it would also be possible to extract all roads close to the destination, including those excluded, and lower the priority of the suggestions according to the travel time from the current location. For example, even if roads 1017-1019 have many available parking spaces, their suggestion priority would be lower than that of roads 1011 and 1015.

[0034] Step S16: If the proposed road 1011 is acceptable, the user selects road 1011 as the destination using the operating device 22. The computing device 10 receives the user's selection result from the operating device 22.

[0035] Step S17: If the user desires a different road than the suggested road 1011, the user can select a different road using the operating device 22. In the example shown in Figure 3, the user moves the cursor 1030 on the map 100, aligns the cursor 1030 with the counter 1022, and presses a selection button (not shown). This selects road 1015 as the destination for guiding the vehicle.

[0036] Step S18: If the user accepts the suggestion, the route search unit 15 of the computing device 10 changes the route to guide the vehicle to the suggested road 1011. If the user does not accept the suggestion, the route search unit 15 changes the route to guide the vehicle to the road 1015 selected by the user.

[0037] 1-2-3. Specific Example 2 The details of each step of the navigation method according to this embodiment will be further explained with reference to Figure 4. Figure 4 is a diagram illustrating a specific example in which the navigation method according to this embodiment is used to search for a parking space in a parking lot. In a parking lot, multiple parking spaces face the road directly. As will be explained below, the navigation method according to this embodiment is effective even in such places. Note that the contents of steps S11-S12 and steps S16-S18 are the same as in Specific Example 1, so their explanation will be omitted.

[0038] Step S13: The road extraction unit 16 of the calculation unit 10 first extracts road 2010 within the parking lot 2002 facing the entrance 2060 of destination 2001. Since road 2010 is longer than the division distance set by parameter 1 of the road selection parameter, the road extraction unit 16 divides road 2010 into roads 2041-2043 that are shorter than the division distance. The road extraction unit 16 then extracts road 2011, which is directly connected to road 2010, and further extracts roads 2012 and 2013, which are directly connected to road 2011. Since road 2013 is longer than the division distance, the road extraction unit 16 divides road 2013 into roads 2044-2046, which are shorter than the division distance.

[0039] Destination 2001 has entrance 2061 in addition to entrance 2060. Entrance 2061 faces road 2017, and there are several parking lots near entrance 2061 that face road 2017. However, the travel time from the vehicle's current location 2070 to road 2017 is extremely long compared to the roads within parking lot 2002. For this reason, the road extraction unit 16 excludes road 2017 from the extraction target according to parameter 2 of the road selection parameter. Also, since parking lot 2002 is one-way, roads 2014-2016 cannot be reached from the current location 2070. For this reason, the road extraction unit 16 excludes roads 2014-2016 from the extraction target.

[0040] Step S14: The calculation unit 10 first aggregates the availability of parking spaces 2050 facing the divided road 2041 and displays the number of available parking spaces on the counter 2020 superimposed on road 2041. Similarly, the calculation unit 10 calculates the total number of available parking spaces for the other extracted roads 2042-2046 and displays the total number of available parking spaces on the counter superimposed on the roads. In addition to displaying the number of available parking spaces, the calculation unit 10 also colors the roads according to the number of available parking spaces.

[0041] Step S15: The road suggestion unit 17 of the calculation unit 10 suggests to the user a road that is close to the entrance 2060 of the destination 1001 from among roads with a predetermined number or more available parking spaces facing the road. Here, the standard number of available parking spaces is assumed to be 7. In the example shown in Figure 4, the roads with 7 or more available parking spaces are roads 2044, 2045, and 2046. Of these, road 2045 is the shortest distance from the entrance 2060, so the road suggestion unit 17 suggests road 2045 to the user. The suggestion is made, for example, by moving the cursor 2030 to the counter 2020 on road 2045 and highlighting road 2045 and the parking spaces 2051 facing road 2045.

[0042] 2. Second Embodiment 2-1. Navigation System The navigation system according to the second embodiment is installed in an autonomous vehicle. The navigation system according to the second embodiment is configured to select the optimal road for finding a parking space for the vehicle from among the roads near the destination when the user sets a destination, and to request the autonomous driving kit to autonomously drive towards that road. The configuration of an autonomous vehicle equipped with the navigation system according to the second embodiment will be described below with reference to Figure 5.

[0043] Figure 5 is a block diagram showing the configuration of an autonomous vehicle 4 equipped with a navigation device 6 according to the second embodiment. The autonomous vehicle 4 comprises a navigation device 6, an external sensor 26, an autonomous driving kit 30, and a vehicle actuator 27. The navigation device 6, the external sensor 26, and the vehicle actuator 27 are communicated to the autonomous driving kit 30.

[0044] The external sensor 26 is a sensor that acquires information about the vehicle's surroundings. The external sensor 26 includes at least one of a camera, millimeter-wave radar, and LiDAR. Based on the surrounding information obtained by the external sensor 26, the autonomous driving kit 30 detects objects present around the vehicle, measures the relative position and relative speed of the detected objects with respect to the vehicle, and recognizes the shape of the detected objects. The autonomous driving kit 30 then generates a target trajectory based on the vehicle's travel path input from the navigation device 6 and the object recognition results, and calculates the control amount for the vehicle actuator 27 to drive the vehicle along the target trajectory. The vehicle actuator 27 includes a drive actuator for driving the vehicle, a braking actuator for braking the vehicle, and a steering actuator for steering the vehicle.

[0045] The physical configuration of the navigation device 6 is the same as that of the navigation device 2 according to the first embodiment. The difference between the navigation device 6 and the navigation device 2 according to the first embodiment lies in the navigation program stored in the ROM 12. In the navigation device 6, the instructions constituting the navigation program are executed by the CPU 11, so that the CPU 11 functions as a vehicle position estimation unit 14, a route search unit 15, a road extraction unit 16, and a road selection unit 18. The functions of the vehicle position estimation unit 14, the route search unit 15, and the road extraction unit 16 are the same as those of the first embodiment.

[0046] The road selection unit 18 obtains the location of parking spaces and information on the availability of parking spaces recorded in the external device 40 via the communication device 23. Next, the road selection unit 18 aggregates the number of accessible available parking spaces for each road extracted by the road extraction unit 16 based on the acquired information. Then, the road selection unit 18 selects the road closest to the destination (the road closest to the entrance of the destination facility) from among the roads that have a predetermined number or more accessible available parking spaces. Once the road selection unit 18 has selected a road, the route search unit 15 searches for a vehicle route to that road. The route searched by the route search unit 15 is input into the autonomous driving kit 30.

[0047] 2-2. Navigation Method Figure 6 is a flowchart showing the navigation method (navigation method according to this embodiment) performed by the navigation device 6 described above. The navigation method according to this embodiment comprises six steps from step S21 to step S26.

[0048] Steps S21-S23 correspond to steps S11-S13 of the navigation method according to the first embodiment. In step S21, the navigation device 6 acquires the destination set by the user and stores it in the storage device 20. In step S22, the navigation device 6 compares the estimated position of its own vehicle with the destination and determines whether the vehicle has arrived near the destination. Then, in step S23, the navigation device 6 extracts roads near the destination by referring to the high-precision map data stored in the storage device 20. When extracting roads, the roads to be extracted are selected according to parameter 2 of the road selection parameter.

[0049] In step S24, the navigation device 6 aggregates the availability of accessible parking spaces for each road extracted in step S23. In step S25, based on the aggregation results in step S24, it selects the optimal road from among the roads with the most accessible available parking spaces. Typically, the road closest to the destination is selected. Then, in step S26, the navigation device 6 transmits the driving route to the selected road to the autonomous driving kit 30 so that the vehicle can autonomously drive towards the selected road.

[0050] 3. Others The navigation technology disclosed herein is also applicable to remote driving systems that remotely drive a vehicle using wireless communication from a remote cockpit. In this case, the navigation device is mounted in the remote cockpit and acquires sensor information from the vehicle via wireless communication. [Explanation of Symbols]

[0051] 2 Navigation device, 4 Autonomous vehicle, 6 Navigation device, 10 Processing unit, 11 CPU, 12 ROM, 13 RAM, 21 Display device, 22 Control device, 23 Communication device, 24 Vehicle status sensor, 25 GPS receiver, 26 External sensor, 27 Vehicle actuator, 30 Autonomous driving kit

Claims

1. At least one processor, A small number of instructions that can be executed by at least one processor are stored. It has at least one memory, The plurality of instructions are provided to at least one processor, To obtain the set destination, After determining that the vehicle has reached the vicinity of the destination, the system extracts multiple roads located near the destination, For each selected road, the number of available parking spaces in all parking lots accessible from that road will be tallied, Select roads where the number of available parking spaces is equal to or greater than a predetermined number as the roads to guide vehicles to for parking, After the aforementioned destination road is selected, the system is configured to perform a route search to guide the vehicle to that road, The aforementioned parking lot is a non-roadside parking lot accessible from the road. A navigation device characterized by the following features.

2. A navigation method using a navigation device, To obtain the set destination, After determining that the vehicle has reached the vicinity of the destination, the system extracts multiple roads located near the destination, For each selected road, the number of available parking spaces in all parking lots accessible from that road will be tallied, Select roads where the number of available parking spaces is equal to or greater than a predetermined number as the roads to guide vehicles to for parking, This includes, after the destination road has been selected, performing a route search to guide the vehicle to that road, The aforementioned parking lot is a non-roadside parking lot accessible from the road. A navigation method characterized by the following features.

3. To obtain the set destination, After determining that the vehicle has reached the vicinity of the destination, the system extracts multiple roads located near the destination, For each selected road, the number of available parking spaces in all parking lots accessible from that road will be tallied, Select roads where the number of available parking spaces is equal to or greater than a predetermined number as the roads to guide vehicles to for parking, The navigation system is configured to perform a route search to guide the vehicle to the selected destination road after the selection has been made. The aforementioned parking lot is a non-roadside parking lot accessible from the road. A navigation program characterized by the following features.

Images