Parking assistance method, parking assistance apparatus, and computer program

Abstract

To improve satisfaction of a user with parking assistance functionality.SOLUTION: A parking assistance method includes: suggesting, to a user, a first parking control method which is a control method for controlling travel of a self-vehicle in parking control (S3); if canceling of parking control in the first parking control method arises, suggesting to the user a second parking control method different from the first parking control method (S6); if the user accepts the proposal of the second parking control method, storing a surrounding environment of a target parking position including layout of obstacles around the target parking position together with the second parking control method in a storage device accessible to the self-vehicle (S8); detecting a surrounding environment again at a time when the self-vehicle is parked after storing the second parking control method in the storage device (S9); and suggesting, to the user, the second parking control method if the detected surrounding environment is similar to the surrounding environment stored in the storage device (S11).SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a parking assistance method, a parking assistance device, and a computer program. [Background technology]

[0002] The parking assistance device described in Patent Document 1 extracts feature points from an image captured of an area where the driver wishes to register a parking position, and registers the feature points in association with the parking position, thereby registering the parking position as a registered parking position.When the vehicle is located near the registered parking position, the device detects the feature points to calculate the registered parking position, and performs parking assistance control to park the vehicle at the registered parking position. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2023-145476 Summary of the Invention [Problem to be solved by the invention]

[0004] However, when implementing a parking assistance function that automatically drives the vehicle to a target parking position, if the parking method does not match the user's preferences or the parking environment, the user may be reluctant to use the parking assistance function. The present invention aims to improve user satisfaction with parking assistance functions. [Means for solving the problem]

[0005] According to one aspect of the present invention, there is provided a parking assistance method for performing parking control to automatically drive a host vehicle to a target parking position. The parking assistance method proposes to a user a first parking control method, which is a control method for controlling the driving of the host vehicle during parking control, and if parking control by the first parking control method is canceled, proposes to the user a second parking control method, which is a control method different from the first parking control method, and if the user accepts the proposal of the second parking control method, stores the surrounding environment of the target parking position, including the arrangement of obstacles around the target parking position, together with the second parking control method, in a storage device accessible to the host vehicle, detects the surrounding environment at the time of parking the host vehicle again after storing the second parking control method in the storage device, and if the detected surrounding environment is similar to the surrounding environment stored in the storage device, proposes to the user the second parking control method. [Effects of the Invention]

[0006] According to the present invention, it is possible to improve user satisfaction with the parking assistance function. [Brief explanation of the drawings]

[0007] [Figure 1] 1 is a diagram illustrating a schematic configuration example of a parking assistance device according to an embodiment; [Figure 2] 10(a) and 10(b) are schematic diagrams illustrating a parking assistance function. [Figure 3] 1 is a flowchart illustrating an example of a parking assistance method according to an embodiment. [Figure 4] 2 is a block diagram illustrating an example of a functional configuration of a controller in FIG. 1. FIG. [Figure 5] FIG. 10 is a diagram showing a first example of a proposal screen for the second parking control method. [Figure 6] FIG. 10 is a diagram showing a second example of a proposal screen for the second parking control method. [Figure 7] FIG. 10 is a diagram showing a third example of a proposal screen for the second parking control method. [Figure 8] FIG. 10 is a diagram showing a first example of a parking control method adjustment screen. [Figure 9] FIG. 10 is a diagram showing a second example of the parking control method adjustment screen. DETAILED DESCRIPTION OF THE INVENTION

[0008] Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the drawings are schematic and may differ from the actual product. Furthermore, the embodiments of the present invention shown below are examples of devices and methods for embodying the technical concept of the present invention, and the technical concept of the present invention does not limit the structure, arrangement, etc. of component parts to those described below. The technical concept of the present invention can be modified in various ways within the technical scope defined by the claims.

[0009] (First embodiment) (composition) 1 is a diagram showing an example of the schematic configuration of a parking assistance device according to an embodiment. A host vehicle 1 is equipped with a parking assistance device 10 that assists the host vehicle 1 in parking at a target parking position. The parking assistance device 10 performs parking control to automatically drive the host vehicle 1 along a target parking path from the current position of the host vehicle 1 to the target parking position. Here, parking control to automatically drive the host vehicle 1 along the target parking path to the target parking position refers to control to automatically drive the host vehicle 1 in whole or in part along the target parking path by controlling the steering angle, driving force, and braking force of the host vehicle 1.

[0010] The positioning device 11 measures the current position of the vehicle 1. The positioning device 11 includes, for example, a Global Navigation System (GNSS) receiver. Map data is stored in a map database (map DB) 12. The map data stored in the map database 12 may be, for example, map data for navigation or high-precision map data suitable for use as a map for automatic driving. The human-machine interface (HMI) 13 is an interface device that exchanges information between the parking assistance device 10 and the user. For example, the HMI 13 may include a display device that is visible to the user as an interface that presents visual information to the user. The HMI 13 may also include a speaker or buzzer as an interface that presents auditory information to the user. The HMI 13 may also include an interface (such as a touch panel, button, switch, lever, dial, or keyboard) that accepts operational input from the user.

[0011] The external sensor 14 detects objects within a predetermined distance range from the host vehicle 1. The external sensor 14 detects the surrounding environment of the host vehicle 1, such as the relative position of the host vehicle 1 and an object present around the host vehicle 1, the distance between the host vehicle 1 and the object, and the direction in which the object is present. The external sensor 14 may include, for example, a camera that captures the surrounding environment of the host vehicle 1. The external sensor 14 may also include a distance measuring device such as a laser range finder, radar, LiDAR, sonar, or infrared sensor. The vehicle sensor 15 detects various information (vehicle information) about the host vehicle 1. For example, the vehicle sensor 15 may include a vehicle speed sensor that detects the traveling speed of the host vehicle 1, a three-axis acceleration sensor that detects the acceleration (including deceleration) of the host vehicle 1 in three axial directions, and a sensor that detects the steering angle of the steering wheel and the steering angle of the steered wheels. The activation switch (activation SW) 16 is a switch that turns on / off the parking assistance function of the parking assistance device 10.

[0012] The controller 17 is an electronic control unit that controls parking of the host vehicle 1. The controller 17 includes a processor 17a and peripheral components such as a storage device 17b. The processor 17a may be, for example, a CPU or an MPU. The storage device 17b may include a semiconductor storage device, a magnetic storage device, an optical storage device, or the like. The functions of the controller 17 described below are realized, for example, by the processor 17a executing a computer program stored in the storage device 17b. The steering actuator 18a controls the steering direction and steering amount of the steering mechanism of the host vehicle 1 in response to a control signal from the controller 17 (the actuator is abbreviated as "ATCR" in the accompanying drawings). The accelerator actuator 18b controls the accelerator opening of the drive device, which is the engine or drive motor, in response to a control signal from the controller 17. The brake actuator 18c activates the braking device in response to a control signal from the controller 17.

[0013] Next, the parking assistance function of the controller 17 will be described with reference to Figures 2(a) and 2(b). When using the parking assistance function of the parking assistance device 10, parking position data, which is information regarding the target parking position where the host vehicle 1 should be parked, is stored (registered) in advance in a storage device accessible to the host vehicle 1. In the example of Figure 2(a), the parking position where the host vehicle 1 should be parked in the parking space 30 is stored as the target parking position. The storage device that stores the target parking position 31 may be, for example, the storage device 17b. In the following description, the storage device 17b is used as an example of a storage device accessible to the host vehicle 1, but the storage device accessible to the host vehicle 1 may also be an external information processing device (for example, a server device).

[0014] The controller 17 extracts targets existing around the target parking position 31 as parking position data and stores (registers) them in the storage device 17b. In the following description, targets around the target parking position 31 stored in the storage device 17b will be referred to as "learned targets." In FIG. 2(a), circles schematically represent learned targets. For example, when a user manually parks the vehicle 1 at the target parking position 31, the controller 17 detects targets around the vehicle 1 using the external sensor 14 and stores the targets as learned targets. For example, targets may be detected from a surrounding image obtained by capturing an image of the surroundings of the vehicle 1 with a camera. For example, edge points where the brightness of adjacent pixels changes by a predetermined amount or points (feature points) with characteristic shapes, such as edges or corners of targets such as road markings, road boundaries, and obstacles, in the captured image obtained by the camera, may be detected as targets.

[0015] The controller 17 stores parking position data including information about the learned targets in the storage device 17b. For example, the parking position data may include data representing the features of the learned targets (hereinafter referred to as "feature data") and data on the relative positional relationship between the target parking position 31 and the learned targets (hereinafter referred to as "relative position data"). As the relative position data, for example, the relative position of the learned targets with respect to the target parking position 31 may be stored. For example, the controller 17 can acquire the position of the learned targets detected when the host vehicle 1 is parked at the target parking position 31 as the relative position of the learned targets. The coordinates of the learned targets and the target parking position 31 in a coordinate system with a fixed point as the reference point (hereinafter referred to as "map coordinate system") may also be stored.

[0016] FIG. 2(b) is an explanatory diagram of an example of processing during execution of parking control in which the controller 17 automatically drives the host vehicle 1 to the target parking position 31. When parking control begins, the controller 17 uses the external sensor 14 to extract targets around the host vehicle 1. In the following description, targets around the host vehicle 1 extracted during execution of parking control are referred to as "surrounding targets." The triangular plots in FIG. 2(b) represent surrounding targets. The controller 17 detects the target parking position 31 by matching the learned targets with the surrounding targets and associating identical feature points, and calculates the relative position of the host vehicle 1 with respect to the target parking position 31 based on the relative positional relationship between the surrounding targets detected during parking assistance execution and the host vehicle 1, and the relative positional relationship between the learned targets associated with the surrounding targets and the target parking position 31.

[0017] For example, the controller 17 calculates the position of the target parking position 31 on a coordinate system (hereinafter referred to as the "vehicle coordinate system") based on the current position of the host vehicle 1. When the coordinates of the learned targets and the target parking position 31 on the map coordinate system are stored in the storage device 17b, the coordinates of the target parking position 31 on the map coordinate system may be converted to coordinates on the vehicle coordinate system based on the positions of the surrounding targets detected when parking assistance is performed and the positions of the learned targets in the map coordinate system. The host vehicle 1's own position on the map coordinate system may be obtained based on the positions of the surrounding targets detected when parking assistance is performed and the positions of the learned targets in the map coordinate system, and the relative position of the host vehicle 1 with respect to the target parking position 31 may be calculated from the difference between the coordinates of the host vehicle 1 and the coordinates of the target parking position 31 in the map coordinate system.

[0018] The controller 17 generates a target parking path 34 from the current position 33 of the host vehicle 1 to the target parking position 31 based on the relative position of the host vehicle 1 with respect to the target parking position 31. The controller 17 also generates a vehicle speed plan (target vehicle speed profile) that sets a target vehicle speed for the host vehicle 1 at each position on the target parking path. The controller 17 controls the steering actuator 18a, accelerator actuator 18b, and brake actuator 18c so that the host vehicle 1 travels along the target parking path 34 at a speed that conforms to the target vehicle speed profile to the target parking position 31 and stops there.

[0019] When generating the target parking path and the target vehicle speed profile, the controller 17 determines the position and shape of the target parking path and the vehicle speed included in the target vehicle speed profile according to the set values ​​of control parameters for controlling the traveling of the host vehicle 1 in parking control. In the following description, the control parameters for controlling the traveling of the host vehicle 1 in parking control may be referred to as "parking control parameters." Hereinafter, the manner and mode of parking control of the host vehicle 1 determined by the set values ​​of the parking control parameters may be referred to as "parking control method."

[0020] The elements of the parking control parameters may be, for example, the speed when parking, the steering speed, the time required for parking, the clearance to an obstacle, the parking style for parking the vehicle 1 at the target parking position 31, and route shape parameters relating to the route shape of the driving route. For example, the parking style may include right-angle parking, parallel parking, and angle parking, which mean parking at a right angle, parallel parking, and angle parking, respectively, relative to the traffic direction of the aisle facing the target parking position 31. For example, the route shape parameters may be the number of turns, parameters of a clothoid curve that forms the travel route, or the shape of the travel route itself. The parking control parameters are not limited to the above examples, and various parameters related to parking control can be used.

[0021] The controller 17 may store parking method data, which is data on parking control methods (i.e., data on setting values ​​of parking control parameters), in advance in a storage device (e.g., storage device 17b) accessible by the host vehicle 1, in association with the target parking position 31. For example, the parking control method may be stored in association with parking position data in the storage device. When performing parking control to park the host vehicle 1 at the target parking position 31, the controller 17 reads out the parking control method stored in association with the target parking position 31 from the storage device, and generates a target parking path 34 and a target vehicle speed profile based on the read parking control method.

[0022] In this way, when parking control is performed based on a parking control method set in advance for the target parking position 31, parking control may not be possible because the parking control method does not match the parking environment. Also, the parking control method may not match the user's preferences (for example, excessive or insufficient vehicle speed, too many turns, approaching an obstacle too closely, etc.). If the parking control method does not match the user's preferences or the parking environment, the user may be reluctant to use the parking assistance function.

[0023] Therefore, in this embodiment, when a parking control method currently set for the target parking position 31 (hereinafter sometimes referred to as the "first parking control method") is proposed, if the parking control by the first parking control method is canceled, a control method different from the first parking control method (hereinafter sometimes referred to as the "second parking control method") is proposed to the user. If the user approves the proposal of the second parking control method, the surrounding environment of the target parking position, including the arrangement of obstacles around the target parking position 31, is stored in a storage device accessible to the host vehicle 1 along with the second parking control method. Then, after the second parking control method is stored in the storage device, the surrounding environment at the time of parking the host vehicle 1 again is detected, and if the detected surrounding environment is similar to the surrounding environment stored in the storage device, the second parking control method is proposed to the user.

[0024] When parking control using the first parking control method is canceled, the first parking control method may not be suited to the surrounding environment at the time of cancellation, and the user may be dissatisfied with the parking assistance function. Therefore, when performing parking control in an environment similar to the surrounding environment at the time of cancellation, a second parking control method different from the first parking control method is proposed. This can improve user satisfaction with the parking assistance function and promote use of the parking assistance function.

[0025] (operation) 3 is a flowchart of an example of the parking assistance method of the embodiment. In step S1, the controller 17 stores the target parking position 31 in the storage device 17b. In step S2, the controller 17 stores a first parking control method to be used when parking the host vehicle 1 at the target parking position 31 in association with the target parking position 31 in the storage device 17b. Thereafter, when parking the vehicle 1 at the target parking position 31, the controller 17 proposes the first parking control method to the user in step S3. In step S4, the controller 17 determines whether or not cancellation of the parking control by the first parking control method has occurred. If cancellation has occurred (step S4: Y), the process proceeds to step S5. If cancellation has not occurred (step S4: N), the process ends.

[0026] In step S5, the controller 17 sets a second parking control method, which is a control method different from the first parking control method. In step S6, the controller 17 proposes the second parking control method to the user. In step S7, the controller 17 determines whether the user has approved the proposal of the second parking control method. If the proposal has been approved (step S7: Y), the process proceeds to step S8. If the proposal has not been approved (step S7: N), the process ends. In step S8, the controller 17 stores the surrounding environment of the target parking position 31, including the arrangement of obstacles around the target parking position 31, together with the second parking control method, in the storage device 17b.

[0027] Thereafter, when parking the vehicle 1 at the target parking position 31, in step S9 the controller 17 detects the surrounding environment of the target parking position 31. In step S10, the controller 17 determines whether the surrounding environment stored in step S8 is similar to the surrounding environment detected in step S9. If the surrounding environments are similar (step S10: Y), the process proceeds to step S11. If the surrounding environments are not similar (step S10: N), the process proceeds to step S14.

[0028] In step S11, the controller 17 proposes a second parking control method to the user. In step S12, the controller 17 determines whether the user has approved the proposal of the second parking control method. If the user has approved the proposal (step S12: Y), the process proceeds to step S13. If the user has not approved the proposal (step S12: N), the process proceeds to step S14. In step S13, the controller 17 executes parking control based on the second parking control method. Then, the process ends. In step S14, the controller 17 executes parking control based on the first parking control method. Then, the process ends.

[0029] (Second embodiment) 4 is a block diagram of an example of the functional configuration of the controller 17. When the user operates the HMI 13 to instruct registration of the target parking position 31, the HMI control unit 50 outputs a map generation command to the map generation unit 55 to store learned target data of the target parking position 31 in the storage device 17b. When the user operates the HMI 13 to instruct start of parking control to the target parking position 31, the HMI control unit 50 outputs a control start command to the parking assistance control unit 51 to start parking control to the target parking position 31. The image conversion unit 52 converts the captured image of the camera into a bird's-eye view image seen from a virtual viewpoint directly above the vehicle 1. The image conversion unit 52 converts the captured image into a bird's-eye view image at predetermined intervals, and accumulates the converted bird's-eye view images along the travel route of the vehicle 1 to generate a surrounding image, which is an image of the area surrounding the vehicle 1.

[0030] The vehicle position calculation unit 53 calculates the current position of the vehicle 1 on the map coordinate system by odometry (for example, dead reckoning) based on the vehicle information output from the vehicle sensor 15 as the vehicle position. The target detection unit 54 detects a target from the surrounding image output from the image conversion unit 52. The target detection unit 54 may detect the position of a feature point of the target and its image feature amount as the target. The target detection unit 54 outputs the position of the detected feature point and the image feature amount as target data to the map generation unit 55 and the target parking position detection unit 57. In addition, in synchronization with the detection of the target, the target detection unit 54 outputs the self-position acquired from the self-position calculation unit 53 to the map generation unit 55 and the target parking position detection unit 57.

[0031] When the map generation unit 55 receives a map generation command from the HMI control unit 50 (i.e., when a registration operation for the target parking position 31 is performed), the map generation unit 55 generates parking position data 56 related to the target parking position 31 and stores it in the storage device 17b. For example, the map generation unit 55 receives the target data and the own position of the vehicle 1 on the map coordinate system synchronized with the target data from the target detection unit 54. The map generation unit 55 acquires position information of the target parking position 31 in the map coordinate system.

[0032] The map generation unit 55 generates relative position data based on the positions of the feature points included in the target data, the position information of the host vehicle 1 synchronized therewith, and the position information of the target parking position 31. The map generation unit 55 acquires feature amount data from the target data output from the target detection unit 54, and stores the relative position data and parking position data 56 including the feature amount data in the storage device 17b.

[0033] When the map generation unit 55 stores the parking position data 56 in the storage device 17b, the parking method setting unit 62 stores parking control method data 63, which is data on the parking control method to be used when parking the vehicle 1 at the target parking position 31 (i.e., data on the setting values ​​of the parking control parameters), in the storage device 17b in association with the parking position data 56 of the target parking position 31. When the parking control method data 63 is stored for the first time, values ​​that are generally used as parking control parameters may be stored as initial values, for example. Next, when the parking assist control unit 51 receives a control start command from the HMI control unit 50, it determines whether or not the current position of the vehicle 1 is near the registered target parking position 31. If the current position of the vehicle 1 is near the registered target parking position 31, the parking assist control unit 51 starts parking control.

[0034] When parking control begins, the target parking position detection unit 57 receives the target data output from the target detection unit 54 as target data of surrounding targets, and in synchronization therewith receives the own position of the vehicle 1 in the map coordinate system. The target parking position detection unit 57 detects the target parking position 31 by matching the learned targets with the surrounding targets and associating targets with the same feature points.

[0035] That is, based on whether matching between the learned objects and the surrounding objects is successful, it is determined whether the target parking position 31 can be detected. If matching is successful (i.e., if the target parking position 31 is detected), the target parking position detection unit 57 calculates the relative position of the vehicle 1 with respect to the target parking position 31 based on the relative positional relationship between the surrounding objects and the vehicle 1 and the relative positional relationship between the learned objects associated with the surrounding objects and the target parking position 31.

[0036] In addition, the parking method setting unit 62 reads out the parking control method data 63 stored in association with the parking position data 56 of the target parking position 31. The target trajectory generating unit 59 calculates a target parking path and a target vehicle speed profile from the current position of the vehicle 1 on the vehicle coordinate system to the target parking position 31 based on the parking control method data 63 read by the parking method setting unit 62. For example, if the parameters of a clothoid curve that forms the driving path are set as the parking control parameters, the clothoid curve that forms the target parking path may be calculated based on the set parameters. Also, if the shape of the driving path itself is set as the parking control parameters, the shape of the target parking path may be determined so as to be equal to the set shape.

[0037] Furthermore, if the number of turns is set as a parking control parameter, the target parking path may be calculated so that the number of turns on the target parking path is equal to the set number. Furthermore, for example, if a parking style is set as a parking control parameter, the target parking path may be calculated so that the host vehicle 1 is parked in the set parking style. In addition, if a margin distance (clearance) to an obstacle is set as a parking control parameter, the target parking path may be calculated so that the distance between the vehicle 1 and an obstacle around the target parking position 31 detected by the external sensor 14 does not become less than the set margin distance.

[0038] In addition, if the parking speed and the time required for parking are set as parking control parameters, the target vehicle speed profile may be calculated so that the driving speed during parking and the time required for parking are equal to these parameters. Furthermore, if a steering speed is set as a parking control parameter, the target vehicle speed profile may be calculated so that the vehicle can travel on the target travel route while adhering to the set steering speed.

[0039] The steering control unit 60 controls the steering actuator 18a so that the host vehicle 1 travels along the target parking path. The vehicle speed control unit 61 controls the accelerator actuator 18b and the brake actuator 18c so that the vehicle speed of the host vehicle 1 changes according to the target vehicle speed profile. When the host vehicle 1 reaches the target parking position 31, the host vehicle 1 is stopped and parking control is completed. The parking assist control unit 51 activates the parking brake and switches the shift position to the parking range.

[0040] Next, an operation of the parking method setting unit 62 will be described. When the parking method setting unit 62 manually parks the host vehicle 1 at the target parking position 31 and registers (stores) the target parking position 31 in the storage device 17b, the parking method setting unit 62 acquires information on parking conditions from the positioning device 11, the external sensor 14, and the vehicle sensor 15 and stores the information in the storage device 17b. For example, the parking conditions may include information on the environment around the host vehicle 1 and the environment around the target parking position 31 (such as the placement of surrounding obstacles), the starting position and parking route when the host vehicle 1 is manually parked at the target parking position 31, the driving speed during parking, and the time required for parking.

[0041] Thereafter, when parking the vehicle 1 at the target parking position 31 by the parking control of the parking assistance device 10, the parking method setting unit 62 proposes to the user the first parking control method, which is a parking control method that has been set in advance. For example, the first parking control method may be a parking control method having parking control parameters set to values ​​commonly used as standard parking control parameters, or may be a parking control method having parking control parameters set in advance according to the user's preferences.

[0042] When performing parking control using the first parking control method, the parking method setting unit 62 acquires information about parking conditions from the positioning device 11, the external sensor 14, and the vehicle sensor 15. When parking control using the first parking control method is successful (i.e., when parking control using the first parking control method is not canceled and parking of the host vehicle 1 into the target parking position 31 is completed using the first parking control method), the parking method setting unit 62 stores the information about the parking conditions acquired during parking control in the storage device 17b. The parking conditions when parking control is successful may include, for example, information about the environment around the vehicle 1 and the target parking position 31 when parking control is performed using the first parking control method (such as the location of surrounding obstacles), the position where parking started, and the parking route.

[0043] When the first parking control method is proposed as described above, the parking method setting unit 62 determines whether or not the parking control according to the first parking control method has been canceled. The parking control may be canceled, for example, by automatic cancellation by the controller 17. For example, the controller 17 detects obstacles around the vehicle 1 or near the target parking path using the external sensor 14 during parking control, and cancels the parking control when an obstacle is detected, when the distance to the obstacle or the clearance is below a certain level, or when interference between the obstacle and the vehicle is predicted. When the parking control is canceled by the controller 17, the controller 17 may automatically stop the host vehicle 1 by braking or the like, shift the vehicle 1 into a parking state by shifting and applying the parking brake, and notify the user that the parking control has been canceled. Alternatively, the controller 17 may not automatically stop the host vehicle 1, but may notify the user of a request to switch driving mode, and then switch the driving mode of the host vehicle 1 to manual driving.

[0044] The parking control may be canceled due to a cancel operation by the user. For example, the controller 17 cancels the parking control when it detects a user operation to turn off the operation switch 16 or a user operation on the steering wheel, accelerator, brake, or shift. When parking control is canceled by the user, the controller 17 automatically stops the host vehicle 1 by braking or the like, notifies the user that parking control has been canceled, and then switches the driving mode of the host vehicle 1 to manual driving. Alternatively, the controller 17 may notify the driver in advance of the control cancellation without automatically stopping the host vehicle 1, and then switch the driving operation to the driver. Alternatively, the controller 17 may notify the user of a request to switch driving mode without stopping the host vehicle 1, and then switch the driving mode of the host vehicle 1 to manual driving.

[0045] Furthermore, the parking method setting unit 62 stores information on the parking conditions when cancellation occurs in the storage device 17b. The parking conditions stored when a cancellation occurs may include, for example, the position of the vehicle 1 at the time the cancellation occurs, information about the environment around the vehicle 1 and the target parking position 31 when the parking control that caused the cancellation was performed (such as the location of surrounding obstacles), the position where parking began, the parking route, the driving speed during parking, and the time required for parking.

[0046] When the parking control is cancelled in this way, a second parking control method, which is a control method different from the first parking control method, is set. For example, if there is a history of successful parking control using the first parking control method in the past, the second parking control method may be set by modifying the first parking control method according to the difference between the parking conditions stored when parking control using the first parking control method was successful and the parking conditions stored when cancellation occurred this time. Furthermore, if there is no history of successful parking control using the first parking control method in the past, the second parking control method may be set by modifying the first parking control method in accordance with the difference between the parking conditions stored when the target parking position 31 was registered in the memory device 17b and the parking conditions stored when the current cancellation occurred.

[0047] For example, if the cause of the cancellation is an automatic cancellation due to approaching an obstacle, and there is a difference in the location of the obstacle between the parking conditions stored when the target parking position 31 was registered in the storage device 17b or when parking control using the first parking control method was successful in the past, and the parking conditions stored when the cancellation occurred this time, the margin distance of the parking control parameters may be changed (increased) to increase the clearance with the obstacle at the location where the cancellation occurred (the position of the vehicle 1 at the time the cancellation occurred). Also, for example, the route shape parameters of the parking control parameters may be changed so as not to pass through the position of the host vehicle 1 at the location where the cancellation occurred. Also, the speed of the parking control parameters may be switched to a low speed so as to reduce the traveling speed at the location where the cancellation occurred.

[0048] Also, for example, if there is a difference in the parking start position between the parking conditions stored when the target parking position 31 was registered or when parking control was successful in the past and the parking conditions stored when cancellation occurred this time, and cancellation occurs because control was started from a position where parking is difficult (for example, when parking is started from a position close to the target parking position 31 in the vehicle width direction in perpendicular parking), the number of turns or steering speed of the parking control parameters may be increased or the vehicle speed may be slowed so that parking control is successful even if parking is started from the same parking start position as when parking control was canceled.

[0049] For example, if the cause of the cancellation is a cancellation operation by the user and the parking control is canceled near an obstacle, the margin distance of the parking control parameter may be changed (increased) so that the clearance with the obstacle at the location where the cancellation occurred is increased. Also, the speed of the parking control parameter may be switched to a low speed so that the driving speed at the location where the cancellation occurred near the obstacle is reduced.

[0050] Furthermore, if the parking time required or the driving speed when the cancellation occurs is longer or the driving speed is lower than the parking time or driving speed when the target parking position 31 was registered (i.e., when parking by manual driving), the speed of the parking control parameters can be increased to approach the parking time or driving speed when the target parking position 31 was registered, or the route shape parameters of the parking control parameters can be set to create a target parking route with a shape that can be followed even when driving at a relatively high speed (for example, by lengthening the length of the clothoid curve that forms the driving route), or the number of turns can be reduced.

[0051] The parking method setting unit 62 proposes the set second parking control method to the user. When the parking method setting unit 62 proposes the second parking control method, the HMI control unit 50 displays (presents) the second parking control method on the display device of the HMI 13. This allows the parking method setting unit 62 to prompt the user for consent as to whether or not to store the second parking control method in the storage device 17b. For example, the HMI control unit 50 may display a target parking path set by the second parking control method. Fig. 5 is a diagram showing a first example of a proposal screen for the second parking control method. For example, the HMI control unit 50 may display a proposal screen 70 on the screen of the HMI 13, which simultaneously shows a first path 71, which is a target parking path according to the first parking control method, and a second path 72, which is a target parking path according to the second parking control method. Furthermore, for example, the HMI control unit 50 may display the turning positions of the first path 71 and the second path 72 on the screen.

[0052] For example, the HMI control unit 50 may generate a proposal screen 70 showing these routes by superimposing an icon representing the position of the vehicle 1 and graphics representing the first route 71 and the second route 72 on the overhead image generated by the image conversion unit 52. Note that in Fig. 5, the first route 71 and the second route 72 represent routes from the current position of the vehicle 1 to a turning point along the parking route to the parking space 30, and reference symbol E represents the shoulder of the passage PW along which the vehicle 1 travels to park in the parking space 30. The same applies to Figs. 6 and 9.

[0053] For example, the HMI control unit 50 may highlight the difference between the first path 71 and the second path 72. The HMI control unit 50 may improve the visibility of the changed parts by drawing a boundary line 73 in the highlighted area or by increasing the brightness or contrast of the highlighted part compared to the non-highlighted part. 6 is a diagram showing a second example of a proposal screen for the second parking control method. The HMI control unit 50 may display a first path 71 and a second path 72 in a superimposed manner. In this case, as in FIG. 5, the HMI control unit 50 may highlight the differences between the first path 71 and the second path 72. Alternatively, only route portions whose route shapes differ by a certain distance or more may be superimposed and displayed. Alternatively, a setting switch button 74 may be provided on the proposal screen 70, and each time the user presses the setting switch button 74, the order of the superimposed routes may be changed or the display color may be changed.

[0054] FIG. 7 is a diagram showing a third example of a proposal screen for the second parking control method. When the parking control parameters of the second parking control method are quantitatively presented to the user, a GUI that quantitatively represents the values ​​of these parking control parameters may be displayed on the display device of the HMI 13. For example, the proposal screen 80 may include a CG of an indicator 81 that visually represents each parking control parameter of the second parking control method (in the example of FIG. 7, the driving speed, the margin of distance to an obstacle, and the number of turns). For example, the indicator 81 may include a position mark 82 that represents the value of the parking control parameter of the first parking control method and an adjustment knob mark 83 that represents the value of the parking control parameter of the second parking control method.

[0055] The parking method setting unit 62 receives an operation by the user to approve the proposal of the set second parking control method via the HMI 13. When the user approves the proposal of the second parking control method, the parking method setting unit 62 acquires information on the surrounding environment around the vehicle 1 and the target parking position 31 from the external sensor 14. For example, the "surrounding environment" may include the empty space around the target parking position 31 (width of the aisle PW, presence or absence of parked vehicles adjacent to the target parking position 31, location of obstacles), parking style (garage parking, parallel parking, diagonal parking), road surface environment (gravel, asphalt, slope), and the environment recognized by the external sensor 14 (road surface pattern, lighting environment, weather). The parking method setting unit 62 stores the acquired surrounding environment and parking control method data 63 of the second parking control method in association with each other in the storage device 17b.

[0056] After the second parking control method is stored, when the host vehicle 1 is to be parked again later, the parking method setting unit 62 acquires information on the ambient environment around the host vehicle 1 and the target parking position 31. For example, when the host vehicle 1 approaches the target parking position 31 again from a point away from the target parking position 31 and parks at the target parking position 31, the parking method setting unit 62 acquires information on the ambient environment around the host vehicle 1 and the target parking position 31. Also, for example, after the second parking control method is stored, when the host vehicle 1 is to be parked at a parking position different from the target parking position 31, the parking method setting unit 62 acquires information on the ambient environment around the host vehicle 1 and the target parking position 31. The parking method setting unit 62 determines whether the surrounding environment acquired from the external sensor 14 is similar to the surrounding environment stored in the storage device 17b in association with the parking control method data 63 of the second parking control method. If these surrounding environments are similar to each other, the parking method setting unit 62 suggests the second parking control method to the user.

[0057] The parking method setting unit 62 receives an operation by the user approving the proposal of the second parking control method via the HMI 13. When the user approves the proposal of the second parking control method, the target trajectory generation unit 59 calculates a target parking path from the current position of the vehicle 1 to the target parking position 31 and a target vehicle speed profile based on the parking control method data 63 of the second parking control method. As a result, the controller 17 performs parking control based on the second parking control method.

[0058] On the other hand, if the surrounding environment acquired from the external sensor 14 and the surrounding environment stored in the storage device 17b are not similar, the parking method setting unit 62 proposes the first parking control method to the user. The parking method setting unit 62 receives an operation by the user approving the proposal of the first parking control method via the HMI 13. When the user approves the proposal of the first parking control method, the target trajectory generation unit 59 calculates a target parking path from the current position of the vehicle 1 to the target parking position 31 and a target vehicle speed profile based on the parking control method data 63 of the first parking control method. As a result, the controller 17 performs parking control based on the first parking control method.

[0059] (Variation) (1) When parking control by the first parking control method is canceled, the parking method setting unit 62 may set the second parking control method based on an instruction input by the user to the HMI 13. For example, when parking control by the first parking control method is canceled, the parking method setting unit 62 may display, on the display screen of the HMI 13, a GUI of an adjustment screen that accepts an adjustment (customization) operation by the user for the first parking control method.

[0060] 8 is a diagram showing a first example of an adjustment screen for the second parking control method. On the adjustment screen 90, change pattern selection buttons 91 to 94 for selecting candidate change patterns for the second parking control method are displayed. The parking method setting unit 62 may set candidate patterns for changing the parking control parameters in a manner similar to the method for setting the parking control parameters of the second parking control method described above, depending on the difference between the parking conditions stored when parking control using the first parking control method was successful or when the target parking position 31 was registered in the memory device 17b and the parking conditions stored when the current cancellation occurred.

[0061] For example, the first candidate change pattern is to increase the driving speed of the parking control parameter, the second candidate is to decrease the driving speed, the third candidate is to increase the margin distance of the parking control parameter, and the fourth candidate is to decrease the number of turns. When the user presses the change pattern selection buttons 91 to 94, the parking method setting unit 62 changes the parking control parameters of the first parking control method according to the first to fourth candidate change patterns, respectively, to set the second parking control method.

[0062] In this way, the parking method setting unit 62 sets the second parking control method in response to the operation of the adjustment screen 90. In other words, the parking method setting unit 62 changes the second parking control method in response to the operation of the adjustment screen by the user.

[0063] 9 is a diagram showing a second example of the adjustment screen for the second parking control method. The parking method setting unit 62 generates a first candidate 96a and a second candidate 96b for a plurality of different target parking path change patterns by modifying the path shape parameters of the parking control parameters for the first parking control method. The adjustment screen 95 displays these first candidate 96a and second candidate 96b as options for the user.

[0064] For example, the parking method setting unit 62 may generate a first candidate 96a that does not swing the front end of the vehicle 1 significantly when turning, and a second candidate 96b that swings the front end of the vehicle 1 significantly when turning. Additionally or alternatively, the parking method setting unit 62 may generate multiple candidate patterns of the target parking route that differ in the number of times of turning. When an operation to select either the first candidate 96a or the second candidate 96b is received, the parking method setting unit 62 sets the route shape parameters of the selected candidate as the route shape parameters of the parking control parameters of the second parking control method.

[0065] The parking method setting unit 62 may allow the user to select a change pattern for the second parking control method as described above, set the second parking control method based on the selected change pattern, and then accept an operation by the user to change the second parking control method in more detail, and adjust the second parking control method in accordance with the change operation. For example, a GUI similar to the proposal screen 80 in Figure 7 may be displayed on the display screen of the HMI 13, and the parking control parameters of the second parking control method may be changed in accordance with an adjustment operation in which the user moves the adjustment knob mark 83 to finely adjust the parking control parameters.

[0066] When the parking method setting unit 62 sets the second parking control method based on instructions input by the user to the HMI 13, it acquires information about the surrounding environment around the vehicle 1 and the target parking position 31 from the external sensor 14, associates the acquired surrounding environment with parking control method data 63 of the second parking control method, and stores them in the memory device 17b.

[0067] (2) When the parking control by the first parking control method is canceled and the parking method setting unit 62 modifies the first parking control method and sets the second parking control method, the parking method setting unit 62 may modify the second parking control method set by the parking method setting unit 62 based on instructions input by the user to the HMI 13.

[0068] (Effects of the embodiment) (1) A parking assistance method that performs parking control to automatically drive a vehicle to a target parking position proposes to a user a first parking control method, which is a control method for controlling the driving of the vehicle during parking control; if parking control using the first parking control method is canceled, a second parking control method, which is a control method different from the first parking control method, is proposed to the user; if the user approves the proposal of the second parking control method, the surrounding environment of the target parking position, including the location of obstacles around the target parking position, is stored in a storage device accessible to the vehicle together with the second parking control method; after the second parking control method is stored in the storage device, the surrounding environment at the time of parking the vehicle again is detected; and if the detected surrounding environment is similar to the surrounding environment stored in the storage device, the second parking control method is proposed to the user.

[0069] In this way, when parking control by the first parking control method is canceled, the first parking control method is not suited to the surrounding environment at the time of cancellation, and the user may be dissatisfied with the parking assistance function. Therefore, when parking in an environment similar to the surrounding environment at the time of cancellation, a second parking control method different from the first parking control method is proposed. This can improve user satisfaction with the parking assistance function and promote use of the parking assistance function.

[0070] (2) The parking control may be cancelled automatically by the vehicle's controller in response to the detection of an obstacle, or may be cancelled by the user. This allows a second parking control method different from the first parking control method to be proposed when the first parking control method does not suit the parking environment or the user's preferences. (3) When the second parking control method is proposed to the user, the parking path when parking control is performed using the first parking control method and the parking path when parking control is performed using the second parking control method may be displayed superimposed on each other, and the difference between the parking path when parking control is performed using the first parking control method and the parking path when parking control is performed using the second parking control method may be highlighted, thereby improving the visibility of the difference between these parking paths.

[0071] (4) The second parking control method may be changed based on an instruction input by the user, thereby enabling parking control according to the user's preferences. (5) The user may be prompted to give consent as to whether or not to store the second parking control method in the storage device, which can prevent the second parking control method from being registered unintentionally by the user. (6) If the detected surrounding environment is not similar to the surrounding environment stored in the storage device, the first parking control method may be proposed to the user, thereby preventing the second parking control method that is not suited to the current surrounding environment from being proposed. [Explanation of symbols]

[0072] 1...own vehicle, 10...parking assistance device, 11...positioning device, 12...map database, 13...human machine interface (HMI), 14...external sensor, 15...vehicle sensor, 16...operation switch, 17...controller, 17a...processor, 17b...storage device, 18a...steering actuator, 18b...accelerator actuator, 18c...brake actuator, 50...HMI control unit, 51...parking assistance control unit, 52...image conversion unit, 53...self-position calculation unit, 54...target detection unit, 55...map generation unit, 56...parking position data, 57...target parking position detection unit, 59...target trajectory generation unit, 60...steering control unit, 61...vehicle speed control unit, 62...parking method setting unit, 63...parking control method data

Claims

1. A parking assistance method for performing parking control to automatically drive a vehicle to a target parking position, comprising: propose to a user a first parking control method that is a control method for controlling traveling of the host vehicle in the parking control; When the parking control by the first parking control method is canceled, a second parking control method that is different from the first parking control method is proposed to the user; When the user approves the proposal of the second parking control method, a surrounding environment of the target parking position including an arrangement of obstacles around the target parking position is stored in a storage device accessible by the host vehicle together with the second parking control method; detecting a surrounding environment at a time when the host vehicle is parked again after the second parking control method is stored in the storage device; If the detected surrounding environment is similar to the surrounding environment stored in the storage device, the second parking control method is suggested to the user. A parking assistance method comprising:

2. 2. The parking assistance method according to claim 1, wherein the cancellation of the parking control is an automatic cancellation in which a controller of the host vehicle cancels the parking control in response to detection of an obstacle.

3. 2. The parking assistance method according to claim 1, wherein the parking control is cancelled by the user.

4. 2. The parking assistance method according to claim 1, wherein, when the second parking control method is proposed to the user, a parking path when the parking control is performed using the first parking control method and a parking path when the parking control is performed using the second parking control method are displayed in a superimposed manner.

5. 2. The parking assistance method according to claim 1, wherein, when the second parking control method is proposed to the user, a difference between a parking path when the parking control is performed using the first parking control method and a parking path when the parking control is performed using the second parking control method is highlighted.

6. The parking assistance method according to claim 1 , wherein the second parking control method is changed based on an instruction input by the user.

7. 2. The parking assistance method according to claim 1, further comprising prompting the user to agree on whether or not to store the second parking control method in the storage device.

8. 2. The parking assistance method according to claim 1, wherein the first parking control method is proposed to the user when the detected surrounding environment is not similar to the surrounding environment stored in the storage device.

9. A parking assistance device that performs parking control to automatically drive a vehicle to a target parking position, a process of proposing to a user a first parking control method which is a control method for controlling the traveling of the host vehicle in the parking control; When the parking control by the first parking control method is canceled, a process of proposing to a user a second parking control method, which is a control method different from the first parking control method; When the user approves the proposal of the second parking control method, a process of storing the surrounding environment of the target parking position, including the arrangement of obstacles around the target parking position, together with the second parking control method in a storage device accessible by the host vehicle; a process of detecting a surrounding environment at a time when the host vehicle is parked again after the second parking control method is stored in the storage device; a process of suggesting the second parking control method to the user when the detected surrounding environment is similar to the surrounding environment stored in the storage device; A parking assistance device comprising: a controller that executes the above.

10. A computer program for performing parking control to automatically drive a vehicle to a target parking position, a process of proposing to a user a first parking control method which is a control method for controlling the traveling of the host vehicle in the parking control; When the parking control by the first parking control method is canceled, a process of proposing to a user a second parking control method, which is a control method different from the first parking control method; When the user approves the proposal of the second parking control method, a process of storing the surrounding environment of the target parking position, including the arrangement of obstacles around the target parking position, together with the second parking control method in a storage device accessible by the host vehicle; a process of detecting a surrounding environment at a time when the host vehicle is parked again after the second parking control method is stored in the storage device; a process of suggesting the second parking control method to the user when the detected surrounding environment is similar to the surrounding environment stored in the storage device; A computer program that causes a controller to execute the above.

Images