Parking assistance device, parking assistance method, and computer program

Abstract

This parking assistance device comprises: a path setting unit (11) for setting target paths (R1-R3) by using a detection result of a sensor device (200); a control region setting unit (12) for setting first control regions (Ar1, Ar1a) and second control regions (Ar2, Ar2a) along the target path; and an operation control unit (13). The first control region is larger than the second control region. The center of the first control region is located farther away from a vehicle as compared with the center of the second control region. The operation control unit controls operation so that the vehicle speed becomes equal to or less than a threshold speed when an obstacle has been detected in the first control region, and controls operation so as to bring the vehicle to a halt at a predetermined deceleration when an obstacle has been detected in the second control region.

Description

Parking assistance device, parking assistance method, and computer program CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application is based on Japanese Application No. 2023-85012, filed on May 24, 2023, the contents of which are incorporated herein by reference.

[0002] The present disclosure relates to a parking assistance device, a parking assistance method, and a computer program.

[0003] Conventionally, parking assistance devices have been proposed that provide parking assistance by guiding a vehicle to a target parking position, etc. For example, a parking assistance device has been proposed that uses detection results from a sensor to detect whether or not an obstacle is present at a planned stopping position on a guided route, and if an obstacle is present, corrects the planned stopping position toward the driver and controls the vehicle to stop at the corrected planned stopping position (see Patent Document 1).

[0004] Japanese Patent Application Laid-Open No. 2021-62658

[0005] However, conventional parking assistance devices do not correct the parking position or reduce the speed when there is an obstacle such as a person a short distance away from the planned driving route (guided route), which can cause anxiety for the vehicle occupants and people nearby the vehicle being parked.

[0006] According to one aspect of the present disclosure, there is provided a parking assistance device that assists parking of a vehicle having a sensor device capable of detecting a surrounding environment. The parking assistance device includes: a route setting unit that sets a target route to a planned parking position for the vehicle using detection results from the sensor device; a control area setting unit that sets a first control area and a second control area along the target route according to the position of the vehicle, the first control area and the second control area including at least a portion of the first control area on the vehicle's direction of travel; and a driving control unit that controls driving of the vehicle. The first control area is larger than the second control area. The center of the first control area is located farther from the vehicle than the center of the second control area. The driving control unit controls the driving of the vehicle so that the vehicle speed is equal to or less than a predetermined threshold speed when the sensor device detects an obstacle within the first control area, and controls the driving of the vehicle so that the vehicle speed is equal to or less than a predetermined threshold speed when the sensor device detects an obstacle within the second control area.

[0007] According to this aspect of the driving assistance device, when an obstacle is detected in a first control region that includes at least a portion of the vehicle in the direction of travel of the vehicle and has a center that is located farther from the vehicle than the center of the second control region, the driving assistance device controls the vehicle so that the vehicle speed is equal to or lower than a predetermined threshold speed, thereby preventing a person or vehicle occupants from feeling uneasy when the person is located slightly away from the target route.In addition, when an obstacle is detected in a second control region that has a center closer to the vehicle than the center of the first control region, the driving assistance device controls the vehicle so that the vehicle stops at a predetermined deceleration, thereby preventing a person or vehicle occupants from feeling uneasy when the person is located slightly away from the target route but closer to the vehicle.

[0008] The above and other objects, features, and advantages of the present disclosure will become more apparent from the following detailed description taken in conjunction with the accompanying drawings, in which Fig. 1 is a block diagram showing a schematic configuration of a parking assistance device according to one embodiment of the present disclosure, Fig. 2 is an explanatory diagram showing an example of a first control region and a second control region in the first embodiment, Fig. 3 is an explanatory diagram showing an example of the first control region and the second control region in the first embodiment, Fig. 4 is a flowchart showing the procedure of parking assistance processing in the first embodiment, Fig. 5 is a timing chart showing an example of a change in vehicle speed, Fig. 6 is a timing chart showing an example of a change in vehicle speed, Fig. 7 is a timing chart showing an example of a change in vehicle speed, FIG. 8 is a block diagram showing the general configuration of a parking assistance device of the second embodiment, FIG. 9 is an explanatory diagram showing an example of the first control region, the second control region, the planned first control region, and the planned second control region in the second embodiment, FIG. 10 is a flowchart showing the procedure of the parking assistance processing in the second embodiment, FIG. 11 is a flowchart showing the procedure of the parking assistance processing in the third embodiment, FIG. 12 is a flowchart showing the procedure of the parking assistance processing in the third embodiment, and FIG. 13 is an explanatory diagram showing an example of the first control region and the second control region in another embodiment.

[0009] A. First Embodiment: A1. Device Configuration: The parking assistance device 100 of the embodiment shown in FIG. 1 is mounted on and used in a vehicle Va. The parking assistance device 100 performs parking assistance for the vehicle Va. In such parking assistance, a target route from the vehicle Va to a planned parking position is set, and the vehicle Va is automatically driven along the target route from the current location of the vehicle Va. At this time, the upper speed limit of the vehicle Va is limited to a predetermined default speed. In this embodiment, the "default speed" is 5 km / h (kilometers per hour). Note that the default speed is not limited to 5 km / h, and any speed may be set.

[0010] In addition to the parking assistance device 100, the vehicle Va is equipped with a sensor device 200, a drive device 410, a steering device 420, and a braking device 430.

[0011] The sensor device 200 is composed of a group of sensors capable of detecting the environment around the vehicle Va. Specifically, the sensor device 200 includes a camera sensor 210 and a radar sensor 220. The camera sensor 210 captures images of the area around the vehicle Va and processes the captured image data to detect information about the area around the vehicle Va, such as obstacles (e.g., other vehicles, pedestrians, structures such as utility poles), and white lines. The camera sensor 210 detects obstacles and white lines in an area extending to the left and right of the vehicle Va's traveling direction. The "traveling direction of the vehicle Va" refers to the forward direction when the vehicle Va is traveling forward, and the backward direction when the vehicle Va is traveling backward. The radar sensor 220 emits electromagnetic waves (radio waves or light) of a predetermined wavelength and detects obstacles around the vehicle Va by receiving reflected waves. The radar sensor 220 may be, for example, a millimeter-wave radar or a LiDAR (Light Detection and Ranging). The LiDAR emits light of a predetermined wavelength while scanning, receives the reflected light, identifies the direction of an obstacle from the position where the peak of the reflected wave is detected, and determines the distance to the obstacle by utilizing the time from the emission of the light to the reception of the reflected wave (TOF: Time Of Flight). The sensor device 200 notifies the parking assistance device 100 of the detection result. In the parking assistance device 100, various processes are performed in functional units (not shown) to obtain information used for driving assistance of the vehicle Va, such as identifying obstacles and detecting white lines.

[0012] The drive device 410 is a group of devices for driving the vehicle Va. The drive device 410 includes devices for generating driving force, such as an engine and a motor generator, various actuators for driving the engine and the motor generator, and an ECU (Electronic Control Unit) for controlling the actuators. The vehicle Va may be configured as any type of vehicle, such as an engine vehicle, a hybrid electric vehicle (HEV), a plug-in hybrid electric vehicle (PHEV), an electric vehicle (EV), or a fuel cell vehicle (FCV, FCHV). The steering device 420 is a group of devices for steering the vehicle Va. The steering device 420 includes a steering wheel, a steering angle sensor, an assist hydraulic device, an actuator for generating hydraulic pressure, and an ECU for controlling steering. The braking device 430 is a group of devices for generating braking force in the vehicle Va. The braking device 430 includes a disc rotor, brake pads, a brake hydraulic device, an actuator for generating hydraulic pressure, and an ECU for controlling braking. The above-mentioned drive device 410, steering device 420, and braking device 430 all communicate with the parking assistance device 100. At this time, the parking assistance device 100 transmits control signals to these devices 410 to 430, and receives signals indicating the operating state of each device from the devices 410 to 430. In this embodiment, the above-mentioned "signals indicating the operating state" include signals indicating the vehicle speed of the vehicle Va, whether or not the brakes are operated, whether or not the turn signal is operated, the amount of wheel rotation, the amount of steering, etc.

[0013] In this embodiment, the parking assistance device 100 is configured as an ECU in which a CPU 10, a ROM 20, and a RAM 30 are configured to be able to communicate with each other via an internal bus 90. The ROM 20 includes a non-volatile memory, such as an EEPROM, and stores a control program in advance. The CPU 10 loads the control program into the RAM 30 and executes it, thereby functioning as a route setting unit 11, a control area setting unit 12, and a driving control unit 13.

[0014] The route setting unit 11 sets a target route to the planned parking position of the vehicle Va using the detection results of the sensor device 200. For example, when the vehicle Va is stopped near a parking space where the vehicle is to be parked in a parking lot and the driver of the vehicle Va issues a parking assistance command via a user interface (not shown), the route setting unit 11 displays the detected parking space on a display device (not shown) using the image captured by the camera sensor 210 and information about surrounding targets obtained by the radar sensor 220. Then, when the driver selects and specifies a parking space where the vehicle is to be parked from among the detected parking spaces as the planned parking position via the user interface, the route setting unit 11 sets a route from the current position of the vehicle Va to the center position of the specified parking space as the target route. Note that any other method may be used to set the target route. For example, if a predetermined parking position is determined in advance, such as a home parking lot, and its latitude and longitude are pre-stored in ROM 20, the route setting unit 11 may obtain the current position (latitude and longitude) of the vehicle Va using a GPS (Global Positioning System) or the like, and set the route from the current position to the predetermined parking position as the target route.

[0015] The control area setting unit 12 sets a first control area and a second control area around the vehicle Va. Both the first control area and the second control area are used as areas for determining the presence or absence of an obstacle in the parking assistance process described below.

[0016] 2 shows a first control region Ar1 and a second control region Ar2 that are set when the vehicle Va moves forward. The first control region Ar1 and the second control region Ar2 are both rectangular regions whose longitudinal direction coincides with the vehicle length direction of the vehicle Va and whose lateral direction coincides with the vehicle width direction of the vehicle Va. The vehicle length direction of the vehicle Va is the direction along the target route R1. In the example of FIG. 2, the rear ends of the first control region Ar1 and the second control region Ar2, which are the rear ends in the traveling direction of the vehicle, coincide with a vehicle rear end REV, which is the rear end in the traveling direction of the vehicle (forward direction).

[0017] 3 shows a first control region Ar1 and a second control region Ar2 that are set when the vehicle Va is reversing. The shapes and sizes of the first control region Ar1 and the second control region Ar2 are the same as those of the first control region Ar1 and the second control region Ar2 shown in FIG. 2. The vehicle length direction of the vehicle Va is the direction along the target route R2. In the example of FIG. 3, the rear ends of the first control region Ar1 and the second control region Ar2 in the traveling direction both coincide with the vehicle rear end FEV in the traveling direction (reverse direction).

[0018] The first control region Ar1 and the second control region Ar2 are both regions that include the vehicle Va on their rear end side. Therefore, both the first control region Ar1 and the second control region Ar2 include a portion of an area on the traveling direction side of the vehicle Va (the forward direction in the example of FIG. 2, and the reverse direction in the example of FIG. 3). The first control region Ar1 is larger than the second control region Ar2. The center position of the first control region Ar1 is located farther from the vehicle Va than the center position of the second control region Ar2. In this embodiment, the longitudinal length L1 of the first control region Ar1 is 20 meters (m). The lateral length W1 of the first control region Ar1 is 12 meters. The longitudinal length L2 of the second control region Ar2 is 12 meters. The lateral length W2 of the second control region Ar2 is 5 meters. The above-mentioned lengths L1, L2, W1, and W2 are merely examples and can be changed as appropriate as long as the relative positional relationship and size relationship between the first control area Ar1 and the second control area Ar2 are not changed.

[0019] As shown in Fig. 2, when the vehicle Va moves forward, a space of length L21 is provided along the target route R1 between the region front end FEA, which is the front end of the second control region Ar2 in the traveling direction, and the vehicle front end FEV, which is the front end of the vehicle Va in the traveling direction. Similarly, as shown in Fig. 3, when the vehicle Va moves backward, a space of length L21 is provided along the target route R2 between the rear end REA, which is the front end of the second control region Ar2 in the traveling direction, and the rear end REV, which is the front end of the vehicle Va in the traveling direction. Details of the length L21 will be described later.

[0020] The control region setting unit 12 repeatedly sets the first control region Ar1 and the second control region Ar2 when the parking assistance device 100 is powered on. Therefore, while the vehicle Va is moving, the positions of the first control region Ar1 and the second control region Ar2 move together with the vehicle Va.

[0021] 1 controls the driving of the vehicle Va. Specifically, the driving control unit 13 controls the drive device 410, the steering device 420, and the braking device 430 in response to the detection results of the sensor device 200 and the driver's operation of the steering wheel, accelerator pedal, brake pedal, etc.

[0022] A2. Parking Assistance Processing: The parking assistance processing shown in Fig. 4 is processing for assisting the parking of the vehicle Va. When an occupant of the vehicle Va issues a command to execute parking assistance via a predetermined user interface provided in the vehicle Va, the above-described setting of the target route is executed. Then, once the setting of the target route is completed, the parking assistance processing shown in Fig. 4 is executed. In this embodiment, the "predetermined user interface" is a menu screen displayed on a display with a touch panel function mounted on the vehicle Va. Instead of such a menu screen, any interface operable by the occupant of the vehicle Va may be used, such as a menu screen of an application pre-installed on a smartphone or the like owned by the occupant, a button provided on a smart key device for the vehicle Va, or a physical switch provided on the instrument panel of the vehicle Va.

[0023] The driving control unit 13 determines whether an obstacle is detected in the first control area Ar1 by the sensor device 200 (step S105). If an obstacle is not detected in the first control area Ar1 (step S105: NO), the process returns to step S105.

[0024] If an obstacle is detected in the first control region Ar1 (step S105: YES), the driving control unit 13 determines whether an obstacle is detected in the second control region Ar2 (step S110). If an obstacle is not detected in the second control region Ar2 (step S110: NO), the driving control unit 13 sets the upper speed limit to a threshold speed (step S115). The threshold speed in step S115 is a speed lower than the default speed. Specifically, in this embodiment, the threshold speed is set to "3 km / h."

[0025] The driving control unit 13 controls the driving of the vehicle Va so that the vehicle speed of the vehicle Va is equal to or less than a threshold speed (step S120).

[0026] Figure 5 shows the change in the speed of the vehicle Va when steps S115 and S120 are executed while the vehicle Va is accelerating. In Figure 5, the horizontal axis represents time t, and the vertical axis represents the speed v of the vehicle Va (hereinafter also simply referred to as "vehicle speed"). In Figure 5, the change Tr1 indicated by a thick solid line represents the change in the vehicle speed when an obstacle is detected within the first control region Ar but outside the second control region Ar. Furthermore, the change Tr2 indicated by a thick dashed line represents the change in the vehicle speed when no obstacle is detected within the first control region Ar1, i.e., when no obstacle is detected in the second control region Ar2 either.

[0027] For example, if the execution of the parking assistance process is instructed at time t0 while the vehicle is stopped and an obstacle such as a person is detected within the second control area Ar2, step S115 is executed, and the upper speed limit is reduced from the default speed v2 to the threshold speed v1, as shown in transition Tr1. Therefore, when the vehicle speed v reaches the threshold speed v1 at time t1, the vehicle speed v stops increasing and remains at the threshold speed v1. Thereafter, when the vehicle reaches a deceleration point on the target route at time t5, the vehicle speed v decreases and becomes zero at time t6.

[0028] In contrast, if the execution of the parking assistance process is instructed at time t0 while the vehicle is stopped and no obstacles such as a person are detected within the second control area Ar2, acceleration continues even after time t1, and when the vehicle speed v reaches the default speed v2 at time t2, acceleration stops and the vehicle speed v maintains the default speed v2. After that, when the vehicle reaches a deceleration point on the target route at time t3, the vehicle speed v decreases and becomes zero at time t4.

[0029] Figure 6 shows the change in the speed of the vehicle Va when steps S115 and S120 are executed while the vehicle Va is traveling at a default speed v2. The vertical and horizontal axes in Figure 6 are the same as those in Figure 5. In Figure 6, a change Tr11 indicated by a thick solid line represents the change in vehicle speed when an obstacle is detected within the first control region Ar1 but outside the second control region Ar2. Furthermore, a change Tr12 indicated by a thick dashed line represents the change in vehicle speed when no obstacle is detected within the first control region Ar1, i.e., when no obstacle is detected in the second control region Ar2 either.

[0030] For example, after the vehicle speed v reaches the vehicle speed v2 at time t11, an obstacle is detected at time t12, step S115 is executed, and the upper speed limit is reduced from the default speed v2 to the threshold speed v1. Then, step S120 is executed, and the vehicle speed v decreases from the default speed v2 toward the threshold speed v1. After that, when the vehicle speed v reaches the threshold speed v1 at time t13, the driving control unit 13 controls the driving so that the vehicle speed maintains the threshold speed v1. When the vehicle reaches a deceleration point on the target route at time t15, the vehicle speed v decreases and becomes zero at time t17.

[0031] In contrast, if no obstacle is detected within the first control area Ar1, as shown in transition Tr12, the vehicle Va continues to travel at the default speed v2, and when it reaches a deceleration point on the target route at time t14, the vehicle speed v decreases and becomes zero at time t16.

[0032] As explained using Figures 5 and 6, when an obstacle is detected within the first control area Ar1 but outside the second control area Ar2, the upper limit of the vehicle speed is reduced from the default speed v2 to the threshold speed v1, and the driving of the vehicle Va is controlled so that the vehicle speed becomes the threshold speed v1, thereby preventing the occupants of the vehicle Va from feeling anxious, and if the obstacle is a person, preventing the person from feeling anxious.

[0033] 4, when it is determined that an obstacle is detected in the second control region (step S110: YES), the driving control unit 13 stops the vehicle Va at a predetermined deceleration (step S125). The deceleration in step S125 is smaller than the deceleration when the deceleration point is reached, i.e., the deceleration from times t5 to t6 and t3 to t4 in FIG. 5, and the deceleration from times t15 to t17 and t14 to t16 in FIG. 6.

[0034] 7, the transition of vehicle speed when step S125 is executed while the vehicle Va is traveling at the default speed v2 is represented by a transition Tr21 in a thick solid line. Note that in FIG. 7, the transition of vehicle speed Tr22 in the comparative example is represented by a thick dashed line. In the comparative example, the vehicle is stopped when an obstacle is detected near the vehicle on the target route.

[0035] As shown in the transition Tr21, after the vehicle speed v reaches the vehicle speed v2 at time t21, when the vehicle Va is traveling at the default speed v2 and an obstacle is detected within the second control area Ar2 at time t22, the driving control unit 13 begins to reduce the vehicle speed relatively slowly and stops the vehicle Va at time t25.

[0036] In contrast, in the comparative example, the vehicle is suddenly braked at time t23 when an obstacle is detected near the vehicle on the target route, and the vehicle is stopped at time t24. Therefore, the sudden braking may cause the vehicle occupants to feel uneasy. Furthermore, if the obstacle is a person, the person may also feel uneasy because the vehicle approaches the person at a relatively high speed. On the other hand, in this embodiment, the vehicle speed is reduced relatively slowly from a relatively early time t22, which prevents the occupants of the vehicle Va and the person who is the obstacle from feeling uneasy.

[0037] As shown in FIG. 4, after the completion of the above-mentioned step S125, after the completion of step S120, and if it is determined in step S105 that no obstacle is detected within the first control area (step S105: NO), the processing returns to step S105.

[0038] As described above with reference to FIGS. 2 and 3 , a space of length L21 is provided along the target route in the direction of travel of the vehicle Va in the second control region Ar2. In this embodiment, length L21 is set to a distance equal to the braking distance when the vehicle is traveling at a speed predetermined as the maximum speed when traveling along the target route, i.e., a default speed. For example, if the braking distance when the default speed is 5 km / h is 6 m, length L21 is set to 6 m. Therefore, in the example of FIG. 2 , when an obstacle is detected near the front end FEA of the second control region Ar2, a collision between the obstacle and the vehicle Va can be prevented. Note that length L21 is not limited to a distance equal to the braking distance, and may be a distance longer than the braking distance.

[0039] According to the parking assistance device 100 of the first embodiment described above, when an obstacle is detected in the first control region Ar1 that includes at least a portion of the vehicle Va in the traveling direction of the vehicle Va and has a center that is located farther from the vehicle Va than the center of the second control region Ar2, the driving of the vehicle Va is controlled to keep the vehicle speed of the vehicle Va equal to or lower than a predetermined threshold speed, so that if a person is present at a position slightly away from the target route R1, it is possible to prevent the person and the occupants of the vehicle Va from feeling uneasy. In addition, when an obstacle is detected in the second control region Ar2 that has a center closer to the vehicle Va than the center of the first control region Ar1, the driving of the vehicle Va is controlled to stop the vehicle Va at a predetermined deceleration, so that if a person is present at a position slightly away from the target routes R1 and R2 but closer to the vehicle Va, it is possible to prevent the person and the occupants of the vehicle Va from feeling uneasy.

[0040] In addition, the length L21 along the target route R1 from the front end FEA of the second control area Ar2, which is the end of the vehicle Va's direction of travel, to the front end FEV of the vehicle, which is the end of the vehicle Va's direction of travel (or the length L21 along the target route R2 from the rear end REA of the area to the rear end REV of the vehicle) is set to a length greater than the braking distance when the vehicle Va is traveling at a speed (default speed) that is predetermined as the maximum speed when traveling along the target routes R1 and R2, so that when an obstacle is detected near the boundary of the second control area Ar2, the vehicle Va can be prevented from colliding with the obstacle.

[0041] B. Second Embodiment: B1. Device Configuration: A parking assistance device 100a of the second embodiment shown in FIG. 8 differs from the parking assistance device 100 of the first embodiment shown in FIG. 1 in that the CPU 10 also functions as the obstacle identification unit 14 and the movement trajectory estimation unit 15. Since the other configurations of the parking assistance device 100a are the same as those of the parking assistance device 100, the same components are given the same reference numerals and detailed descriptions thereof will be omitted. Note that the obstacle identification unit 14 and the movement trajectory estimation unit 15, like the other functional units 11 to 14, are realized by the CPU 10 loading a control program stored in the ROM 20 into the RAM 30 and executing it.

[0042] The obstacle identification unit 14 identifies whether a detected obstacle is a stationary object or a moving object by using multiple detection results obtained at different times by the sensor device 200. Specifically, if an obstacle that is the same as an obstacle detected previously is detected and the position of the obstacle is different between the previous detection and the current detection, the obstacle is identified as a moving object.

[0043] The movement trajectory estimation unit 15 estimates the future movement trajectory of the obstacle identified as a moving object by the obstacle identification unit 14. This estimation is performed by identifying the movement direction and movement speed of the obstacle from the history of the detected obstacle's position (a history including position information of the obstacle detected before and information related to the detection time), and estimating the position of the obstacle when it is detected next time or later based on this information. Note that the estimation of the movement trajectory of the obstacle is not limited to the above-mentioned method, and may be realized by any method that utilizes the detection result of the sensor device 200.

[0044] In this embodiment, the control region setting unit 12 sets a planned first control region and a planned second control region in addition to the first control region and the second control region described above.

[0045] As shown in FIG. 9 , a first planned control area Ar11 and a second planned control area Ar12 are set ahead of the first control area Ar1 and the second control area Ar2 in the direction of travel of the vehicle Va. The shape and size of the first planned control area Ar11 are the same as those of the first control area Ar1. The shape and size of the second planned control area Ar12 are the same as those of the second control area Ar2. In this embodiment, a gap G1 of a predetermined size exists between the positions of the first control area Ar1 and the first planned control area Ar11 along the direction of travel (target route R1). In this embodiment, the size of the gap G1 is determined in advance through experiments and simulations as a distance such that, if a person m1 located a predetermined distance d1 away from the first control area Ar1 at a certain time walks toward the vehicle Va at a predetermined walking speed, the person m1 will be within the first control area Ar1 at the next detection timing. Note that the predetermined distance d1 may be, for example, 2 m. The predetermined walking speed may be, for example, 2.5 km / h.

[0046] B2. Parking Assistance Processing: The parking assistance processing of the second embodiment shown in Figure 10 differs from the parking assistance processing of the first embodiment shown in Figure 4 in that steps S130, S135, and S140 are additionally executed. Since the other steps of the parking assistance processing of the second embodiment are the same as those of the first embodiment, the same steps are denoted by the same reference numerals and detailed descriptions thereof will be omitted.

[0047] In the above-mentioned step S105, if it is determined that no obstacle is detected within the first control area (step S105: NO), the movement trajectory estimation unit 15 estimates the movement trajectory of a moving object among the obstacles detected outside the first control area (step S130).

[0048] The driving control unit 13 determines whether the movement trajectory estimated in step S130 intersects with the planned first control area Ar11 (step S135). If it is determined that the movement restriction intersects with the planned first control area Ar11 (step S135: YES), the driving control unit 13 determines whether the movement trajectory estimated in step S130 intersects with the planned second control area Ar12 (step S140). "The movement trajectory intersects with the control areas (the planned first control area Ar11 and the planned second control area Ar12)" means that the movement trajectory intersects with the boundary line of each control area.

[0049] If it is determined that the movement trajectory does not intersect with the planned second control region Ar12 (step S140: NO), that is, if the movement trajectory intersects with the boundary of the planned first control region Ar11 but does not intersect with the boundary of the planned second control region Ar12, the above-mentioned steps S115 and S120 are executed. Therefore, in this case, the driving of the vehicle Va is controlled so that the vehicle speed is equal to or less than the threshold speed.

[0050] On the other hand, if it is determined that the movement trajectory intersects with the planned second control region Ar12 (step S140: YES), that is, if the movement trajectory intersects with the boundary of both the planned first control region Ar11 and the planned second control region Ar12, the above-described step S125 is executed. Therefore, in this case, the vehicle Va decelerates at a predetermined deceleration and stops.

[0051] If it is determined in step S135 that the movement trajectory does not intersect with the planned first control area Ar11, and if it is determined in step S140 that the movement trajectory does not intersect with the planned second control area Ar12, the processing returns to step S105.

[0052] The parking assistance device 100a of the second embodiment described above achieves the same effects as the parking assistance device 100 of the first embodiment. In addition, the parking assistance device 100a identifies whether a detected obstacle is a stationary object or a moving object, estimates the future movement trajectory of the moving object, controls driving so that the vehicle speed is equal to or lower than a threshold speed when the movement trajectory intersects with the planned first control area Ar11, and controls driving so that the vehicle Va is stopped at a predetermined deceleration when the movement trajectory intersects with the planned second control area Ar12. Therefore, the driving of the vehicle Va can be controlled in anticipation of the future movement of the obstacle, making it possible to suppress anxiety felt by people as moving objects who are farther away from the target route R1, and further suppressing anxiety felt by the occupants of the vehicle Va.

[0053] C. Third Embodiment: The configuration of the parking assistance device 100 of the third embodiment is the same as the configuration of the parking assistance device 100 of the first embodiment, so the same components are denoted by the same reference numerals and detailed description thereof will be omitted.

[0054] The parking assistance process of the third embodiment shown in Figures 11 and 12 differs from the parking assistance process of the first embodiment shown in Figure 4 in that, after completing steps S120 and S125, the process does not return to step S105, but executes steps S150 to S170 shown in Figure 12. Since the other steps of the parking assistance process of the third embodiment are the same as those of the first embodiment, the same steps are denoted by the same reference numerals and detailed descriptions thereof will be omitted.

[0055] As shown in Figures 11 and 12, after completion of step S120 and after completion of step S125, the driving control unit 13 determines whether the detected obstacle has moved from within the first control area Ar1 to outside the first control area Ar1 based on the detection result of the sensor device 200 (step S150).

[0056] If it is determined that the detected obstacle has moved from within the first control region Ar1 to outside the first control region Ar1 (step S150: YES), the driving control unit 13 resets the upper speed limit to the default speed (step S155). The driving control unit 13 controls driving so that the vehicle speed is equal to or less than the default speed (step S160). For example, if step S155 is completed while the vehicle Va is traveling at the threshold speed and no acceleration request is subsequently issued, the vehicle Va continues traveling while maintaining the vehicle speed at the threshold speed. On the other hand, for example, if step S155 is completed while the vehicle Va is traveling at the threshold speed and an acceleration request is subsequently issued, the vehicle Va accelerates, and the vehicle speed increases beyond the threshold speed (3 km / h) up to the default speed (5 km / h). After step S160 is executed, the process returns to step S105 of FIG. 11 . When an obstacle moves from the inside to the outside of the first control area Ar1, which is relatively wide and whose boundary is relatively far from the vehicle Va, the possibility that the obstacle will approach very close to or collide with the vehicle Va in the future is low. Therefore, in this case, by returning the upper speed limit to the default speed, it is possible to prevent the time required for the parking operation from being unnecessarily extended.

[0057] On the other hand, if it is determined that the detected obstacle has not moved from within the first control area Ar1 to outside the first control area Ar1 (step S150: NO), the driving control unit 13 determines whether the detected obstacle has moved from within the second control area Ar2 to outside the second control area Ar2 (step S165).

[0058] If it is determined that the detected obstacle has moved from within the second control region Ar2 to outside the second control region Ar2 (step S165: YES), the driving control unit 13 continues stopping the vehicle (step S170). If the vehicle Va is within the second control region Ar2, the above-mentioned step S125 is executed, and the driving control unit 13 attempts to stop the vehicle Va by reducing the vehicle speed at a predetermined deceleration. Therefore, step S170 means that this operation will be continued, and therefore the driving control unit 13 does not actually perform any new operation in step S170. On the other hand, if it is determined that the detected obstacle has not moved from within the second control region Ar2 to outside the second control region Ar2 (step S165: NO), the processing returns to step S105 of FIG. 11 . In this case, as long as an obstacle is present within the second control region Ar2, steps S105, S110, and S125 shown in FIG. 11 are executed in this order, so that the vehicle Va decelerates and stops at a predetermined deceleration. Therefore, in this case, the driving control unit 13 does not substantially perform any new operation. Even if the obstacle moves from the inside to the outside of the second control region Ar2, whose boundary is relatively close to the vehicle Va, the possibility that the obstacle will approach or collide with the vehicle Va in the future remains high. Therefore, by continuing to decelerate and stop the vehicle Va at a predetermined deceleration, it is possible to prevent the vehicle Va from repeatedly performing and not performing a stopping operation when an obstacle detected outside the second control region is again detected within the second control region. Repeatedly performing and not performing a stopping operation can cause unpredictable behavior, which can make the occupants of the vehicle Va and people around the vehicle Va feel uneasy. In this embodiment, it is possible to prevent such uneasiness from being felt by the occupants and people around the vehicle Va.

[0059] The parking assistance device 100 of the third embodiment described above provides the same effects as the parking assistance device 100 of the first embodiment. In addition, when an obstacle is detected outside the first control area Ar1 after the obstacle is detected within the first control area Ar1, the driving control unit 13 stops controlling the driving of the vehicle to keep the vehicle speed equal to or lower than the threshold speed, thereby preventing the vehicle speed from being limited even when a collision with an obstacle is not expected, and preventing the time required for parking from being unnecessarily long.

[0060] Once an obstacle is detected in the second control region Ar2, which is closer to the vehicle Va than the first control region Ar1, there is a high possibility that the obstacle will be detected again in the second control region Ar2, even if an obstacle is subsequently detected outside the second control region Ar2. According to the parking assistance device 100 of the third embodiment, the driving control unit 13 continues to control the driving of the vehicle Va to decelerate and stop the vehicle Va at a predetermined deceleration when an obstacle is detected outside the second control region Ar2 after the obstacle is detected within the second control region Ar2. This prevents the vehicle Va from repeatedly performing and not performing a stopping operation when an obstacle detected outside the second control region Ar2 is again detected within the second control region Ar2. This prevents the occupants of the vehicle Va and people around the vehicle Va from feeling uneasy due to the repeated execution and non-execution of the stopping operation.

[0061] D. Other Embodiments: (D1) In each embodiment, the first control region Ar1 and the second control region Ar2 are rectangular regions, but the present disclosure is not limited thereto. They may be sector-shaped regions with their vertices at the installation positions of the sensor device 200 on the vehicle Va, or circular regions with the vehicle Va at their centers. Furthermore, as shown in FIG. 13 , if at least a portion of the target route R3 is arc-shaped along a road, the first control region Ar1a and the second control region Ar2a, which are set when the vehicle Va travels through such a section while turning, may have a shape that follows the target route R3. Similarly, the planned first control region Ar11 and the planned second control region Ar12 may also have any shape.

[0062] (D2) In the second embodiment, a first scheduled control area Ar11 and a second scheduled control area Ar12 are set, and the upper speed limit is limited or the vehicle Va is decelerated to a stop in anticipation of future approach between the vehicle Va and an obstacle (moving object) depending on whether the control areas Ar11 and Ar12 intersect with the trajectory of the moving object. However, the present disclosure is not limited to this. In a configuration in which the vehicle Va includes a control device (hereinafter referred to as a "safety support control device") for controlling a collision prevention safety function, separate from the parking assistance device 100, 100a, and the safety support control device detects (predicts) whether or not a future collision between the vehicle and a moving object will occur and the time of the collision, the parking assistance device 100, 100a may further receive the prediction result. If the prediction result indicates a "collision," the upper speed limit may be limited or the vehicle Va may be decelerated to a stop immediately or at a time a predetermined time prior to the predicted collision time. Even with such a configuration, the same effects as those of the second embodiment can be achieved. The above-mentioned "collision prevention safety function" refers to a function that, for example, when a collision between the vehicle Va and an obstacle is predicted, automatically steers or brakes to avoid the collision, warns the occupants by turning on predetermined lamps or emitting warning sounds, or automatically increases the tension of the seat belts to prevent the occupants from being thrown into the vehicle cabin.

[0063] (D3) In the third embodiment, when a moving object moves from inside to outside the first control region Ar1, the upper speed limit is returned to the default speed and driving is controlled so that the vehicle speed is equal to or less than the default speed. When a moving object moves from inside to outside the second control region Ar2, the stopping operation of the vehicle Va is continued. However, the present disclosure is not limited to this. Even when a moving object moves from inside to outside the first control region Ar1, the upper speed limit may be maintained at the threshold speed. Furthermore, when a moving object moves from inside to outside the second control region Ar2, the stopping operation of the vehicle Va may be stopped and the process may return to step S105.

[0064] (D4) In each embodiment, only a portion of each of the first control regions Ar1, Ar1a and the second control regions Ar2, Ar2a is located in the direction of travel of the vehicle Va. However, the present disclosure is not limited to this. All of the first control regions Ar1, Ar1a and the second control regions Ar2, Ar2a may be located in the direction of travel of the vehicle Va. Even with this configuration, the same effects as those of each embodiment are achieved.

[0065] (D5) In each embodiment, the deceleration in step S125 is smaller than the deceleration when a deceleration point on the target route is reached, but the present disclosure is not limited to this. The deceleration in step S125 may be the same as or larger than the deceleration when a deceleration point on the target route is reached. In this case, too, the comparative example achieves the same effect as each embodiment by satisfying the requirement that the deceleration be smaller than the deceleration when an obstacle is detected near the vehicle on the target route.

[0066] (D6) The parking assistance device 100, 100a and the methods therefor described herein may be implemented by a special-purpose computer configured by configuring a processor and memory programmed to perform one or more functions embodied in a computer program. Alternatively, the parking assistance device 100, 100a and the methods therefor described herein may be implemented by a special-purpose computer configured by configuring a processor with one or more dedicated hardware logic circuits. Alternatively, the parking assistance device 100, 100a and the methods therefor described herein may be implemented by one or more special-purpose computers configured by combining a processor and memory programmed to perform one or more functions with a processor configured with one or more hardware logic circuits. Furthermore, the computer program may be stored as instructions executed by a computer on a computer-readable non-transitory tangible recording medium.

[0067] The present disclosure may be realized in various forms, such as a parking assistance method, a parking assistance device, a computer program for realizing the parking assistance method, a non-transitory recording medium on which such a computer program is recorded, etc.

[0068] The present disclosure is not limited to the above-described embodiments and can be realized in various configurations without departing from the spirit thereof. For example, the technical features in each embodiment corresponding to the technical features in the form described in the Summary of the Invention section can be appropriately replaced or combined to solve some or all of the above-described problems or achieve some or all of the above-described effects. Furthermore, if a technical feature is not described as essential in this specification, it can be appropriately deleted. [Mode 1] A parking assistance device that assists in parking of a vehicle having a sensor device capable of detecting a surrounding environment, comprising: a route setting unit (11) that sets a target route (R1 to R3) to a planned parking position of the vehicle (Va) by using a detection result of the sensor device (200); a control area setting unit (12) that sets a first control area (Ar1, Ar1a) and a second control area (Ar2, Ar2a) along the target route according to a position of the vehicle, the first control area and the second control area including at least a portion of an area on the side of the vehicle in a traveling direction of the vehicle; and a driving control unit (13) that controls driving of the vehicle, wherein the first control area is larger than the second control area, and the center of the first control area is located farther from the vehicle than the center of the second control area, and the driving control unit controls the driving so that the vehicle speed is equal to or less than a predetermined threshold speed when the sensor device detects an obstacle in the first control area, A parking assistance device (100, 100a) that controls the driving so as to stop the vehicle at a predetermined deceleration when the sensor device detects an obstacle in the second control area.[Mode 2] In the parking assistance device according to Mode 1, the first control area and the second control area are both rectangular areas whose longitudinal direction is the vehicle length direction of the vehicle and whose transverse direction is the vehicle width direction of the vehicle, and are set as areas that include the vehicle, and a length (L21) along the target route from an area front end (FEA, REA) that is an end of the second control area in the direction of travel of the vehicle to a vehicle front end (FEV, REV) that is also an end of the second control area in the direction of travel of the vehicle is set to be equal to or longer than the braking distance when the vehicle is traveling at a speed that is predetermined as a maximum speed when traveling along the target route. [Mode 3] The parking assistance device according to Mode 1 or Mode 2, further comprising: an obstacle identification unit (14) that identifies whether a detected obstacle is a stationary object or a moving object by using detection results obtained by the sensor device at different times; and a movement trajectory estimation unit (15) that estimates a future movement trajectory of the obstacle identified as a moving object, wherein the control area setting unit further sets a planned first control area (Ar11) and a planned second control area (Ar12) that are the first control area and the second control area after a predetermined time has elapsed, and the driving control unit controls the driving so that the vehicle speed is equal to or less than the threshold speed when the identified movement trajectory intersects with the planned first control area, and controls the driving so that the vehicle stops at the predetermined deceleration when the identified movement trajectory intersects with the planned second control area. [Mode 4] The parking assistance device according to any one of Modes 1 to 3, wherein, when an obstacle is detected outside the first control region after the obstacle is detected within the first control region, the driving control unit stops controlling the driving to keep the vehicle speed equal to or lower than the threshold speed. [Mode 5] The parking assistance device according to any one of Modes 1 to 4, wherein, when an obstacle is detected outside the second control region after the obstacle is detected within the second control region, the driving control unit continues controlling the driving to stop the vehicle at a predetermined deceleration.[Mode 6] A parking assistance method for assisting parking of a vehicle having a sensor device capable of detecting a surrounding environment by using a parking assistance device, comprising: a step of setting, in the parking assistance device, a target route to a planned parking position of the vehicle using a detection result of the sensor device; a step of setting, in the parking assistance device, a first control area and a second control area along the target route according to a position of the vehicle, the first control area and the second control area including at least a portion of an area on a side of the vehicle in a traveling direction of the vehicle; and a driving control step of controlling driving of the vehicle in the parking assistance device, wherein the first control area is larger than the second control area, and a center of the first control area is located farther from the vehicle than a center of the second control area, and the driving control step includes: a step of controlling the driving of the vehicle so that a vehicle speed of the vehicle is equal to or lower than a predetermined threshold speed when an obstacle is detected in the first control area by the sensor device; and a step of controlling the driving of the vehicle so that a vehicle speed of the vehicle is equal to or lower than a predetermined threshold speed when an obstacle is detected in the second control area by the sensor device.[Mode 7] A computer program for assisting parking of a vehicle having a sensor device capable of detecting a surrounding environment, the computer program including: a function for setting a target route to a planned parking position of the vehicle using detection results of the sensor device; a function for setting a first control area and a second control area along the target route according to a position of the vehicle, the first control area and the second control area including at least a portion of an area on the side of the vehicle in the direction of travel of the vehicle; and a driving control function for controlling driving of the vehicle, wherein the first control area is larger than the second control area, and a center of the first control area is located farther from the vehicle than a center of the second control area, and the driving control function includes: a function for controlling the driving of the vehicle when an obstacle is detected in the first control area by the sensor device so that the vehicle speed is equal to or lower than a predetermined threshold speed; and a function for controlling the driving of the vehicle when an obstacle is detected in the second control area by the sensor device so that the vehicle is stopped at a predetermined deceleration.

Claims

1. A parking assistance device that assists parking of a vehicle having a sensor device that can detect a surrounding environment, a route setting unit (11) that sets a target route (R1 to R3) to a planned parking position of the vehicle (Va) using the detection result of the sensor device (200); a control area setting unit (12) that sets, along the target route, a first control area (Ar1, Ar1a) and a second control area (Ar2, Ar2a) according to a position of the vehicle, the first control area and the second control area including at least a part of an area on the side of the vehicle in a traveling direction of the vehicle; A driving control unit (13) for controlling the driving of the vehicle; Equipped with the first control region is larger than the second control region; a center of the first control region is located farther from the vehicle than a center of the second control region; The operation control unit When the sensor device detects an obstacle within the first control area, the driving is controlled so that the vehicle speed is equal to or less than a predetermined threshold speed; When the sensor device detects an obstacle within the second control area, the driving is controlled to stop the vehicle at a predetermined deceleration; an obstacle identification unit (14) that identifies whether a detected obstacle is a stationary object or a moving object by using detection results obtained at different times by the sensor device; a movement trajectory estimation unit (15) that estimates a future movement trajectory of the obstacle identified as a moving object; Furthermore, The control region setting unit further sets a planned first control region (Ar11) and a planned second control region (Ar12), which are the first control region and the second control region after a predetermined time has elapsed, The operation control unit When the identified movement trajectory intersects with the planned first control region, the driving is controlled so that the vehicle speed is equal to or less than the threshold speed; When the identified movement trajectory intersects with the planned second control region, the driving is controlled so as to stop the vehicle at the predetermined deceleration. Parking assistance device (100, 100a).

2. 2. The parking assistance device according to claim 1, the first control region and the second control region are both rectangular regions whose longitudinal direction is the vehicle length direction of the vehicle and whose transverse direction is the vehicle width direction of the vehicle, and are set as regions that include the vehicle, A parking control device, wherein a length (L21) along the target route from a front end (FEA, REA) of the second control area, which is the end of the vehicle's direction of travel, to a front end (FEV, REV) of the vehicle, which is the end of the vehicle's direction of travel, is set to a length equal to or greater than the braking distance when the vehicle is traveling at a speed predetermined as the maximum speed when traveling along the target route.

3. 3. The parking assistance device according to claim 1, the driving control unit stops controlling the driving so that the vehicle speed is equal to or less than the threshold speed when an obstacle is detected within the first control area and then the obstacle is detected outside the first control area.

4. 3. The parking assistance device according to claim 1, The driving control unit continues to control the driving so as to stop the vehicle at a predetermined deceleration when the obstacle is detected outside the second control area after the obstacle is detected within the second control area.

5. A parking assistance method for assisting parking of a vehicle having a sensor device capable of detecting a surrounding environment by using a parking assistance device, comprising: a step of setting a target route to a planned parking position of the vehicle using a detection result of the sensor device in the parking assistance device; a control area setting step of setting, in the parking assistance device, a first control area and a second control area along the target route according to a position of the vehicle, the first control area and the second control area including at least a portion of an area on a side of the vehicle in a traveling direction of the vehicle; a driving control step of controlling driving of the vehicle in the parking assistance device; a step of identifying whether the detected obstacle is a stationary object or a moving object by using detection results obtained by the sensor device at different times; estimating a future movement trajectory of the obstacle identified as a moving object; Equipped with the first control region is larger than the second control region; a center of the first control region is located farther from the vehicle than a center of the second control region; the control region setting step further includes a step of setting a planned first control region and a planned second control region, which are the first control region and the second control region after a predetermined time has elapsed, The operation control step includes: When the sensor device detects an obstacle in the first control area, controlling the driving of the vehicle so that the vehicle speed is equal to or less than a predetermined threshold speed; a step of controlling the driving so as to stop the vehicle at a predetermined deceleration when the sensor device detects an obstacle in the second control area; controlling the driving so that the vehicle speed is equal to or less than the threshold speed when the identified movement trajectory intersects with the planned first control region; controlling the driving of the vehicle to stop the vehicle at the predetermined deceleration when the identified movement trajectory intersects with the planned second control region; A parking assistance method comprising:

6. A computer program for assisting parking of a vehicle having a sensor device capable of detecting a surrounding environment, a function of setting a target route to a planned parking position of the vehicle using the detection results of the sensor device; a control area setting function that sets, along the target route, a first control area and a second control area according to a position of the vehicle, the first control area and the second control area including at least a portion of an area on the vehicle's traveling direction side relative to the vehicle; a driving control function for controlling driving of the vehicle; a function of identifying whether a detected obstacle is a stationary object or a moving object by utilizing detection results obtained at different times by the sensor device; a function of estimating a future movement trajectory of the obstacle identified as a moving object; This is realized by a computer, the first control region is larger than the second control region; a center of the first control region is located farther from the vehicle than a center of the second control region; the control region setting function includes a function of further setting a planned first control region and a planned second control region, which are the first control region and the second control region after a predetermined time has elapsed, The operation control function is a function of controlling the driving of the vehicle so that the vehicle speed is equal to or less than a predetermined threshold speed when the sensor device detects an obstacle in the first control area; a function of controlling the driving so as to stop the vehicle at a predetermined deceleration when an obstacle is detected within the second control area by the sensor device; a function of controlling the driving so that the vehicle speed is equal to or less than the threshold speed when the identified movement trajectory intersects with the planned first control area; a function of controlling the driving so as to stop the vehicle at the predetermined deceleration when the identified movement trajectory intersects with the planned second control region; a computer program comprising: