Parking assistance device, parking assistance method, and recording medium

Abstract

The present invention relates to a parking assistance device that accurately selects a parking area deemed suitable for a vehicle from among a plurality of parking areas arranged side by side with respect to a passageway. The parking assistance device in one embodiment includes: a detection unit that detects parking areas, also known as parking areas, among the plurality of parking areas arranged side by side with respect to the passageway; a calculation unit that, when a plurality of such parking areas are detected within a predetermined range, calculates, for each of the parking areas, a passageway-direction distance between a first reference position in the parking area, which is set closer to the passageway than halfway in the parking direction, and a second reference position set for the vehicle; a selection unit that selects the parking area with the shortest passageway-direction distance among the plurality of such parking areas; and a display control unit that causes a display unit to emphasize the selected parking area.

Description

Technical Field

[0001] Embodiments of the present invention relate to a parking assistance device, a parking assistance method, and a recording medium. Background Art

[0002] Conventionally, in vehicle parking assistance technology, for example, when a plurality of parking areas arranged side by side relative to a road are detected, a parking area deemed appropriate for the vehicle is selected and highlighted.

[0003] Patent Document 1: Japanese Patent Application Laid-Open No. 2018-176910

[0004] In the above-mentioned conventional technology, there is a situation where the selected parking area is actually not appropriate based on the relationship between the direction of the passage and the parking direction of the parking area, and there is room for improvement. Summary of the Invention

[0005] A parking assistance device according to an embodiment includes: a detection unit for detecting a parking area (i.e., a parking area) from among a plurality of parking areas arranged side by side with respect to a passageway; a calculation unit for calculating, for each of the parking areas, a passageway-direction distance between a first reference position in the parking area, set closer to the passageway than halfway in the parking direction, and a second reference position set for the vehicle, when the plurality of parking areas are detected within a predetermined range; a selection unit for selecting the parking area with the shortest passageway-direction distance from among the plurality of parking areas; and a display control unit for causing a display unit to emphasize the selected parking area. This configuration allows the selected parking area to be a practically appropriate parking area, regardless of whether the passageway direction and the parking direction in the parking area are perpendicular or oblique, for example.

[0006] Furthermore, in the parking assistance device of the embodiment, the first reference position is the midpoint of a line at one end of the passageway in the parking area. This configuration further reduces the possibility that an inappropriate parking area will be selected, particularly when the passageway direction and the parking direction in the parking area are at an angle, by setting the first reference position on the parking area side to the midpoint of a line at one end of the passageway.

[0007] Furthermore, in the parking assistance system of the embodiment, the second reference position is the position of the driver's seat in the host vehicle. With this configuration, by setting the second reference position on the host vehicle side to the position of the driver's seat, for example, a parking area that appears less awkward to the driver who ultimately decides on the parking area for the host vehicle can be selected and highlighted.

[0008] In addition, the parking assistance method of the embodiment includes: a detection step of detecting a parking area (i.e., a parking area) from among a plurality of parking areas arranged side by side with respect to a passageway; a calculation step of, when a plurality of the parking areas are detected within a predetermined range, calculating, for each of the parking areas, a distance in the passageway direction between a first reference position in the parking area, which is set closer to the passageway than halfway in the parking direction, and a second reference position set in the vehicle; a selection step of selecting the parking area with the shortest distance in the passageway direction from among the plurality of parking areas; and a display control step of causing a display unit to emphasize the selected parking area. With this configuration, for example, whether the relationship between the passageway direction and the parking direction in the parking area is perpendicular or inclined, the selected parking area can be selected as a practically appropriate parking area.

[0009] In addition, a recording medium according to an embodiment stores a parking assistance program configured to cause a computer to execute the following steps: a detection step of detecting a parking area (i.e., a parking area) from among a plurality of parking areas arranged side by side with respect to a passageway; a calculation step of, when a plurality of the parking areas are detected within a predetermined range, calculating, for each of the parking areas, a passageway-direction distance between a first reference position in the parking area, which is set closer to the passageway than halfway in the parking direction, and a second reference position set in the vehicle; a selection step of selecting the parking area from among the plurality of parking areas having the shortest passageway-direction distance; and a display control step of causing a display unit to emphasize the selected parking area. With this configuration, for example, regardless of whether the passageway direction and the parking direction in the parking area are perpendicular or oblique, the selected parking area can be selected as a practically appropriate parking area. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 This is an illustrative perspective view showing a state in which a portion of the vehicle interior of the vehicle according to the embodiment is seen through.

[0011] Figure 2 It is an exemplary top view (bird's-eye view) of the vehicle according to the embodiment.

[0012] Figure 3 This is a diagram showing an example of an instrument panel of a vehicle according to an embodiment when viewed from the rear of the vehicle.

[0013] Figure 4 This is an exemplary block diagram of the configuration of the parking assistance system according to the embodiment.

[0014] Figure 5 This is an exemplary block diagram of the functional configuration of the ECU of the parking assist system according to the embodiment.

[0015] Figure 6 It is an explanatory diagram of a method of selecting a parking area in a comparative example.

[0016] Figure 7 It is an explanatory diagram of a method of selecting a parking area in a comparative example.

[0017] Figure 8 It is an explanatory diagram of a method of selecting a parking area in a comparative example.

[0018] Figure 9 It is an explanatory diagram of a method for selecting a parking area in the embodiment.

[0019] Figure 10 This is an exemplary flowchart of the processing of the ECU of the parking assist system according to the embodiment.

[0020] Figure 11 It is an explanatory diagram of a method for detecting the front end line of a parking area in the embodiment.

[0021] Figure 12 It is an explanatory diagram of a method for detecting the front end line of a parking area in the embodiment.

[0022] Figure 13 It is an explanatory diagram of a method for detecting a path direction in an embodiment.

[0023] Figure 14 It is a diagram showing an example of a display screen in the parking assistance system according to the embodiment.

[0024] Explanation of reference numerals: 1…vehicle, 8…display device, 14…ECU, 100…parking assist system, 141…acquisition unit, 142…detection unit, 143…calculation unit, 144…selection unit, 145…display control unit. DETAILED DESCRIPTION

[0025] The following describes exemplary embodiments of the parking assistance device, parking assistance method, and parking assistance program of the present invention. The configurations of the embodiments described below and the operations, results, and effects achieved by these configurations are merely examples. The present invention can also be implemented with configurations other than those disclosed in the following embodiments, and can achieve at least one of the various effects and derivative effects derived from the basic configurations.

[0026] The vehicle 1 of this embodiment can be, for example, a vehicle powered by an internal combustion engine (not shown), i.e., an internal combustion engine vehicle; a vehicle powered by an electric motor (not shown), i.e., an electric vehicle or a fuel cell vehicle; a hybrid vehicle powered by both of these; or a vehicle equipped with other drive sources. Furthermore, the vehicle 1 can be equipped with various transmissions and various devices, such as systems and components, required to drive the internal combustion engine and electric motor. Furthermore, the configuration, number, and layout of the devices driving the wheels 3 in the vehicle 1 can be variously configured.

[0027] First, refer to Figures 1 to 4 , the structure of the vehicle 1 according to this embodiment will be described. Figure 1 This is an illustrative perspective view showing a state in which a portion of the vehicle interior of the vehicle 1 according to the embodiment is seen through. Figure 2 It is an exemplary top view (bird's-eye view) of the vehicle 1 according to the embodiment. Figure 3 This is a diagram showing an example of an instrument panel of the vehicle 1 according to the embodiment when viewed from the rear of the vehicle. Figure 4 This is an exemplary block diagram of the configuration of the parking assistance system 100 according to the embodiment.

[0028] like Figure 1 As shown, the vehicle body 2 constitutes a passenger compartment 2a (not shown) for passengers. Within the passenger compartment 2a, a steering wheel 4, an accelerator 5, a brake 6, and a shifter 7 are provided, facing the driver's seat 2b. The steering wheel 4 is, for example, a steering wheel protruding from the instrument panel 24. The accelerator 5 is, for example, an accelerator pedal located under the driver's feet. The brake 6 is, for example, a brake pedal located under the driver's feet. The shifter 7 is, for example, a shift lever protruding from the center console. The steering wheel 4, accelerator 5, brake 6, and shifter 7 are not limited to these.

[0029] Furthermore, a display device 8 serving as a display output unit and a sound output device 9 serving as a sound output unit are provided within the vehicle cabin 2a. The display device 8 is, for example, an LCD (Liquid Crystal Display) or an OELD (Organic Electro-Luminescent Display). The sound output device 9 is, for example, a speaker. Furthermore, the display device 8 is covered by a transparent operation input unit 10, such as a touch panel. Passengers can visually view the image displayed on the screen of the display device 8 via the operation input unit 10. Furthermore, passengers can perform operation inputs by touching, pressing, or moving the operation input unit 10 with a finger or the like at a position corresponding to the image displayed on the screen of the display device 8. These display device 8, sound output device 9, operation input unit 10, etc., are provided on a monitor device 11 located, for example, in the center of the instrument panel 24 in the vehicle width direction, i.e., in the left-right direction. The monitor device 11 may include operation input units (not shown), such as switches, dials, joysticks, and buttons. Furthermore, a sound output device (not shown) may be provided at another location in the vehicle cabin 2a other than the monitor device 11, and sound may be output from the sound output device 9 of the monitor device 11 and the other sound output devices.

[0030] In addition, a display device 12 different from the display device 8 is provided in the vehicle compartment 2a. Figure 3 As illustrated, the display device 12 is, for example, disposed on the instrument panel 25 of the instrument panel 24, approximately in the center of the instrument panel 25, between the speed display 25a and the rotation speed display 25b. The screen 12a of the display device 12 is smaller than the screen 8a of the display device 8. The display device 12 can primarily display images representing information related to parking assistance for the vehicle 1. The amount of information displayed on the display device 12 may be less than that displayed on the display device 8. The display device 12 may be, for example, an LCD, an OLED, or the like. Furthermore, the information displayed on the display device 12 may also be displayed on the display device 8.

[0031] In addition, if Figure 1 、 2 As shown in the example, the vehicle 1 is a four-wheeled vehicle having two front wheels 3F and two rear wheels 3R. All four wheels 3 can be configured to be steerable. Figure 4As illustrated, the vehicle 1 has a steering system 13 for steering at least two wheels 3. The steering system 13 has an actuator 13a and a torque sensor 13b. The steering system 13 is electrically controlled by an ECU 14 (Electronic Control Unit) or the like, so as to operate the actuator 13a. The steering system 13 is, for example, an electric power steering system, an SBW (Steer By Wire) system, or the like. The steering system 13 supplements the steering force by adding torque, i.e., auxiliary torque, to the steering unit 4 through the actuator 13a, or steers the wheels 3 through the actuator 13a. In this case, the actuator 13a can steer either one wheel 3 or multiple wheels 3. In addition, the torque sensor 13b detects, for example, the torque applied by the driver to the steering unit 4.

[0032] In addition, if Figure 2 As illustrated, the vehicle body 2 is provided with, for example, four imaging units 15a to 15d as a plurality of imaging units 15. The imaging unit 15 is, for example, a digital camera with built-in imaging elements such as a CCD (Charge Coupled Device) and a CIS (CMOS Image Sensor). The imaging unit 15 can output video data at a predetermined frame rate. The imaging unit 15 has a wide-angle lens or a fisheye lens, and can capture a range of, for example, 140° to 190° in the horizontal direction. In addition, the optical axis of the imaging unit 15 is set to face obliquely downward. Thus, the imaging unit 15 sequentially captures the external environment around the vehicle body 2, including the road surface on which the vehicle 1 can move and the area where the vehicle 1 can park, and outputs it as captured image data.

[0033] The imaging unit 15a is, for example, located at the end 2e on the rear side of the vehicle body 2 and is provided on the wall below the door 2h of the trunk. The imaging unit 15b is, for example, located at the end 2f on the right side of the vehicle body 2 and is provided on the right rearview mirror 2g. The imaging unit 15c is, for example, located at the front side of the vehicle body 2, that is, at the end 2c on the front side in the vehicle front-to-rear direction, and is provided on the front bumper, etc. The imaging unit 15d is, for example, located at the left side of the vehicle body 2, that is, at the end 2d on the left side in the vehicle width direction, and is provided on the rearview mirror 2g, which is a protruding portion on the left side. The ECU 14 can perform calculation processing and image processing based on the image data obtained by the multiple imaging units 15 to generate an image with a wider viewing angle or a virtual bird's-eye view image of the vehicle 1 viewed from above.

[0034] Furthermore, the ECU 14 recognizes partition lines and the like shown on the road surface around the vehicle 1 based on the image from the imaging unit 15 , and detects (extracts) parking areas shown by the partition lines and the like.

[0035] In addition, if Figure 1 、2 As shown in the example, the vehicle body 2 is provided with, for example, four ranging units 16a to 16d and eight ranging units 17a to 17h, serving as a plurality of ranging units 16 and 17. The ranging units 16 and 17 are, for example, sonars that emit ultrasonic waves and capture their reflected waves. Sonars can also be referred to as sonar sensors or ultrasonic detectors. Based on the detection results of the ranging units 16 and 17, the ECU 14 can determine the presence of objects such as obstacles around the vehicle 1 and the distance to such objects. In other words, the ranging units 16 and 17 are examples of detection units that detect objects. Furthermore, the ranging unit 17 can be used, for example, to detect objects at relatively close distances, while the ranging unit 16 can be used, for example, to detect objects at a relatively long distance, farther than the ranging unit 17. Furthermore, the ranging unit 17 can be used, for example, to detect objects in front of and behind the vehicle 1, while the ranging unit 16 can be used to detect objects to the sides of the vehicle 1.

[0036] In addition, if Figure 4 As shown, in the parking assist system 100, in addition to the ECU 14, monitor device 11, steering system 13, and distance measuring units 16 and 17, the braking system 18, steering angle sensor 19, acceleration sensor 20, shift sensor 21, and wheel speed sensor 22 are electrically connected via an in-vehicle network 23, which serves as an electrical communication line. The in-vehicle network 23 is configured, for example, as a CAN (Controller Area Network). The ECU 14 can control the steering system 13, braking system 18, and other components by sending control signals via the in-vehicle network 23. Furthermore, the ECU 14 can receive detection results from the torque sensor 13b, brake sensor 18b, steering angle sensor 19, distance measuring units 16 and 17, acceleration sensor 20, shift sensor 21, and wheel speed sensor 22, as well as operation signals from the operation input unit 10, etc., via the in-vehicle network 23.

[0037] The ECU 14 includes, for example, a CPU 14a (Central Processing Unit), a ROM 14b (Read Only Memory), a RAM 14c (Random Access Memory), a display control unit 14d, a sound control unit 14e, and an SSD 14f (Solid State Drive, Flash Memory). The CPU 14a can read programs installed and stored in non-volatile storage devices such as the ROM 14b and perform various calculations and controls based on these programs. The RAM 14c temporarily stores various data used in the calculations of the CPU 14a. Furthermore, the display control unit 14d primarily performs image processing using image data obtained by the imaging unit 15 and synthesizing image data displayed on the display device 8, among other calculations performed by the ECU 14. Furthermore, the sound control unit 14e primarily performs sound data output by the sound output device 9, among other calculations performed by the ECU 14. The SSD 14f is a rewritable non-volatile storage unit that can store data even when the power to the ECU 14 is turned off. Furthermore, the CPU 14a, ROM 14b, RAM 14c, and the like can be integrated into the same package. Furthermore, the ECU 14 can be configured to use another logic processor or logic circuit, such as a DSP (Digital Signal Processor), in place of the CPU 14a. Furthermore, an HDD (Hard Disk Drive) can be provided in place of the SSD 14f, or the SSD 14f or HDD can be provided separately from the ECU 14.

[0038] The brake system 18 is, for example, an ABS (Anti-lock Brake System) that suppresses brake lock, an anti-skid device (ESC: Electronic Stability Control) that suppresses side slip of the vehicle 1 when turning, an electric brake system that increases braking force (performs brake assist), a BBW (Brake By Wire) brake system, etc. The brake system 18 applies braking force to the wheels 3 and thus to the vehicle 1 via the actuator 18a. In addition, the brake system 18 can detect signs of brake lock, wheel 3 idling, and side slip based on the rotation difference between the left and right wheels 3, and perform various controls. The brake sensor 18b is, for example, a sensor that detects the position of the movable part of the brake operating part 6. The brake sensor 18b can detect the position of the brake pedal, which is a movable part. The brake sensor 18b includes a displacement sensor.

[0039] The steering angle sensor 19 is a sensor that detects the steering amount of the steering control unit 4, such as the steering wheel. For example, the steering angle sensor 19 is constructed using a Hall element. The ECU 14 obtains information from the steering angle sensor 19 regarding the driver's steering amount on the steering control unit 4 and the steering amount of each wheel 3 during automatic steering, and performs various control operations. Furthermore, the steering angle sensor 19 detects the rotation angle of the rotating parts of the steering control unit 4. The steering angle sensor 19 is an example of an angle sensor.

[0040] The acceleration sensor 20 is a sensor that detects the position of a movable portion of the accelerator operating unit 5, for example. The acceleration sensor 20 can detect the position of an accelerator pedal as a movable portion. The acceleration sensor 20 includes a displacement sensor.

[0041] The shift sensor 21 is a sensor that detects the position of a movable portion of the shift operating unit 7. The shift sensor 21 can detect the position of a movable portion such as a lever, arm, or button. The shift sensor 21 may include a displacement sensor or be configured as a switch.

[0042] The wheel speed sensor 22 detects the rotational speed of the wheel 3, or the number of revolutions per unit time. The wheel speed sensor 22 outputs a number of wheel speed pulses representing the detected number of revolutions as a sensor value. For example, the wheel speed sensor 22 can be configured using a Hall effect element or the like. The ECU 14 calculates the movement amount of the vehicle 1 and other parameters based on the sensor values ​​obtained from the wheel speed sensor 22 and performs various control operations. Alternatively, the wheel speed sensor 22 may be installed in the braking system 18. In this case, the ECU 14 obtains the detection results of the wheel speed sensor 22 via the braking system 18.

[0043] The configurations, arrangements, electrical connection methods, and the like of the various sensors and actuators described above are merely examples, and various settings (changes) are possible.

[0044] Next, refer to Figure 5 Next, the functional configuration of the ECU 14 of the parking assist system 100 according to the embodiment will be described. Figure 5 FIG. 1 is an exemplary block diagram of the functional configuration of the ECU 14 of the parking assist system 100 according to the embodiment. Figure 5 As shown in FIG. 1 , the ECU 14 includes an acquisition unit 141, a detection unit 142, a calculation unit 143, a selection unit 144, and a display control unit 145 as functional components. Figure 4 In the ECU 14, each of the components 141 to 145 is implemented by the CPU 14a executing, for example, a parking assistance program stored in the ROM 14b. Alternatively, the components 141 to 145 may be implemented using two or more ECUs. Alternatively, each of the components 141 to 145 may be implemented using hardware.

[0045] The acquisition unit 141 acquires detection results of the torque sensor 13b, the brake sensor 18b, the steering angle sensor 19, the distance measuring unit 16, the distance measuring unit 17, the acceleration sensor 20, the shift sensor 21, the wheel speed sensor 22, etc., the captured image of the imaging unit 15, the operation signal of the operation input unit 10, etc.

[0046] The detection unit 142 detects parking spaces (i.e., parking areas) among a plurality of parking spaces arranged side by side with respect to the passageway. For example, the detection unit 142 detects parking spaces (parkable areas) based on the captured image acquired by the acquisition unit 141. More specifically, the detection unit 142 detects parking spaces by detecting dividing lines, curbs, steps, other vehicles, and the like from the captured image through image processing such as edge detection.

[0047] In addition, for example, the detection unit 142 can also detect parking areas such as quadrilaterals through machine learning such as deep learning. In this case, for example, in deep learning, the learning phase processing and the inference phase processing are performed as follows. First, in the learning phase processing, teacher data (correct answer data) that defines a parking area using four-point parking spaces at four corners is used for learning to create a learning model. More specifically, for example, a function is constructed using parameters to define a loss for the correct answer data and minimize the loss to perform learning. Then, in the inference phase, the learning model is used to detect (estimate) parking areas based on the captured image.

[0048] When multiple parking areas are detected within a specified range (e.g., within multiple adjacent parking areas), the calculation unit 143 calculates, for each parking area, the distance in the access road direction (distance in the access road direction) between a first reference position in the parking area, set on the access road side, halfway in the parking direction, and a second reference position set in the vehicle. The first reference position is, for example, the midpoint of a line (hereinafter also referred to as the "front end line") at one end of the access road side of the parking area. The second reference position is, for example, the position of the driver's seat of the vehicle.

[0049] The selection unit 144 selects a parking area having the shortest distance in the passage direction among the plurality of parking areas.

[0050] The display control unit 145 controls the display of various information on the display device 8 and the display device 12. For example, the display control unit 145 displays a plurality of parking areas on the display device 8 and highlights the parking area selected by the selection unit 144.

[0051] Here, before describing specific examples of the processing of each unit 141 to 145, for ease of understanding, refer to Figures 6 to 8, the method of selecting a parking area in the comparative example (conventional technology) is explained. Figures 6 to 8 It is an explanatory diagram of a method of selecting a parking area in a comparative example.

[0052] exist Figures 6 to 8 In the figure, parking areas (parkable areas) PS1 to PS3 are shown in a parking lot, demarcated by white lines WL. The direction of travel VD of vehicle 1 coincides with the direction of the access road. Positions R1 to R3 are the positions to which the rear axle center (the center position in the vehicle width direction of the rear axle supporting the rear wheels) moves when vehicle 1 is accommodated in parking areas PS1 to PS3, respectively. Furthermore, in the comparative example, the distances in the access road direction between positions R1 to R3 and the driver's seat position DS of vehicle 1 are calculated, and the available parking area with the shortest distance in the access road direction is selected and highlighted on the display.

[0053] In this method, for example, Figure 7 As shown, when the direction of the access road and the parking direction in the parking area are perpendicular (when viewed from above), the distance in the access road between position R1 and driver's seat position DS is distance D1, the distance in the access road between position R2 and driver's seat position DS is distance D2, and the distance in the access road between position R3 and driver's seat position DS is distance D3. Therefore, distance D2 is the shortest distance in the access road, so parking area PS2 is selected and highlighted on the display. This way, from the driver's perspective, parking area PS2, the closest of parking areas PS1 to PS3, is highlighted on the display, eliminating any sense of disharmony.

[0054] However, in this method, e.g. Figure 8 As shown, when the relationship between the aisle direction and the parking direction in the parking area is oblique (oblique when viewed from above the plumb line), the aisle-direction distance between position R1 and driver's seat position DS is distance D11, the aisle-direction distance between position R2 and driver's seat position DS is distance D12, and the aisle-direction distance between position R3 and driver's seat position DS is distance D13. In other words, the aisle-direction distance is the shortest at distance D11, so parking area PS1 is selected and highlighted on the display. As a result, from the driver's perspective, parking area PS2, the closest of parking areas PS1 to PS3, is not highlighted on the display, while parking area PS1 is highlighted, causing a sense of disharmony. Furthermore, from the perspective of the actual moving distance during parking, parking area PS1 is not preferred due to its longer moving distance.

[0055] Thus, in the comparative example, the aforementioned access-direction distance is calculated using the rear wheel axle center used when parking assistance is executed. While this process is efficient, there is room for improvement in cases where the selected parking area is actually inappropriate based on the relationship between the access-direction and the parking direction within the parking area. The parking assistance system 100 of this embodiment can improve this. Now, let's return to the description of this embodiment.

[0056] Figure 9 : is an explanatory diagram of a method for selecting a parking area in an embodiment. In this embodiment, for example, Figure 9 As shown, when the relationship between the access road direction and the parking direction in the parking area is oblique, the access road distance is calculated using positions F1 to F3, the center of the front end line of the parking area, rather than the rear wheel axle center (positions R1 to R3). Consequently, through processing by calculation unit 143, the access road distance between position F1 and driver's seat position DS is distance D21, the access road distance between position F2 and driver's seat position DS is distance D22, and the access road distance between position F3 and driver's seat position DS is distance D23. Since the access road distance is the shortest at distance D22, selection unit 144 selects parking area PS2, and display control unit 145 highlights parking area PS2 on display device 8. Therefore, from the driver's perspective, parking area PS2, the closest of parking areas PS1 to PS3, is highlighted on display device 8, eliminating any sense of discomfort. Furthermore, from the perspective of the actual travel distance during parking, parking area PS2 is preferred because it is shorter than parking area PS1.

[0057] Next, refer to Figure 10 Next, the processing of the ECU 14 in the parking assist system 100 according to the embodiment will be described. Figure 10 This is an exemplary flowchart of the processing of the ECU 14 of the parking assist system 100 according to the embodiment. Note that, regarding the main operating element, elements other than the components 141 to 145 are referred to as "ECU 14."

[0058] First, in step S1 , the detection unit 142 detects a parking area based on the captured image acquired by the acquisition unit 141 .

[0059] Next, in step S2, the ECU 14 determines whether a parking assistance application (app) has been activated via the operation input unit 10 or the like. If so, the process proceeds to step S3; if not, the process returns to step S1. It is assumed that the driver activates the parking assistance application after stopping the vehicle 1. Furthermore, it is assumed that multiple parking areas are detected within a predetermined range.

[0060] In step S3 , the calculation unit 143 calculates the distance in the passage direction between the midpoint of the front end line and the position of the driver's seat for each parking area.

[0061] Next, in step S4 , the selection unit 144 selects a parking area having the shortest passageway-direction distance among the plurality of parking areas.

[0062] Next, in step S5 , the display control unit 145 displays a plurality of parking available areas on the display device 8 , and highlights the parking available area selected by the selection unit 144 .

[0063] here, Figure 14 FIG. 1 is a diagram showing an example of a display screen in the parking assistance system 100 according to the embodiment. Figure 14 As shown, in area A1, the display device 8 displays a plurality of available parking areas PS1 to PS3 in addition to the vehicle. Furthermore, the available parking area PS2 selected by the selection unit 144 among the plurality of available parking areas PS1 to PS3 is highlighted. Below this area, a button B1 labeled "Start parking assistance in this parking area" and a button B2 labeled "Change parking area" are displayed.

[0064] Return to Figure 10 After step S5, in step S6, the ECU 14 determines whether a parking assist start operation is performed by operating the input unit 10 or the like (in other words, whether there is a Figure 14 If yes, go to step S9, if no, go to step S7.

[0065] In step S7, the ECU 14 determines whether there is a change operation of the parking area (in other words, whether there is a change operation of the parking area). Figure 14 If yes, go to step S8, if no, return to step S6.

[0066] In step S8, the ECU 14 Figure 14 In the screen shown, the parking area is changed and the process returns to step S6. For example, each time the process of step S8 is performed, the parking area that is highlighted is sequentially changed. In addition, the user may also be able to specify the parking area after the change.

[0067] In step S9 , the ECU 14 starts parking assistance. Next, in step S10 , the ECU 14 controls the acceleration and deceleration mechanism and the steering mechanism of the vehicle 1 to execute parking assistance.

[0068] Next, the ECU 14 determines whether the vehicle 1 has reached the target parking position, and if so, proceeds to step S12 , and if not, returns to step S10 . In step S12 , the ECU 14 ends the parking assist.

[0069] Next, refer to Figures 11 to 13 , to provide additional explanation for the above technology. Figure 11 It is an explanatory diagram of a method for detecting the front end line of a parking area in the embodiment.

[0070] exist Figure 11 In the diagram shown, line L1 passes through the center point of the curved portion of white line WL1 on the access side (the upper side in the diagram) and is perpendicular to the straight portion of white line WL1 or the parking direction in parking area PS. Separately, line L2 passes through the center point of the curved portion of white line WL2 on the access side and is perpendicular to the straight portion of white line WL2 or the parking direction in parking area PS. In this case, line L3, or the leading edge line, can be detected as the line midway between lines L1 and L2 (width W1 = width W2).

[0071] in addition, Figure 12 1 is an explanatory diagram of a method for detecting the front end line of a parking area in an embodiment. Figure 11 Compared with the case of , the difference is that the white line information is not used. Figure 12 In the diagram shown, line L11 passes through the front end of vehicle V1 on the access road side (the upper side in the diagram) and is perpendicular to the parking direction in parking area PS. Line L12 passes through the front end of vehicle V2 on the access road side and is perpendicular to the parking direction in parking area PS. In this case, line L13, the front end line, can be detected as a line midway between lines L11 and L12 (width W11 = width W12).

[0072] Alternatively, it is possible to pre-identify whether the direction of the access road is perpendicular or oblique to the parking direction in the parking area. In this case, the perpendicularity or obliqueness can be determined based on the angle of the parking direction in the parking area relative to the access road. Therefore, it is necessary to first accurately detect the access road direction.

[0073] The passage direction can be detected as follows. For example, the current direction of the vehicle can be used as the passage direction. In addition, the direction when the vehicle has traveled straight for a predetermined distance or more can be used as the passage direction. Figure 13 Other detection methods are described.

[0074] Figure 13 : is an illustration of a method for detecting a path direction in an embodiment. Figure 13 As shown in (a), a straight line connecting the points at one end of the passage side of the plurality of white lines WL21 to WL24 may be used as the passage direction L21. Figure 13As shown in (b), the path direction L31 may be obtained by calculating an approximate straight line using the front end points of the path side of the plurality of vehicles V11 to V15 and the least square method or the like.

[0075] As described above, according to the parking assistance system 100 of this embodiment, the selected parking area can be a practically appropriate parking area regardless of whether the relationship between the passage direction and the parking direction in the parking area is perpendicular or inclined.

[0076] In addition, by making the first reference position on the parking area side the midpoint of the line at one end of the passage side, especially when the relationship between the passage direction and the parking direction in the parking area is inclined, the possibility that the selected parking area is not actually an appropriate parking area can be further reduced.

[0077] Furthermore, by setting the second reference position on the host vehicle side to the position of the driver's seat, for example, a parking area that is less awkward for the driver who has finally decided on the parking area for the host vehicle can be selected and highlighted.

[0078] Alternatively, the parking assistance program executed by the CPU 14a of this embodiment may be provided as a file in an installable or executable format recorded on a computer-readable recording medium such as a CD-ROM, floppy disk (FD), CD-R, or DVD (Digital Versatile Disk).

[0079] Furthermore, the parking assistance program may be provided by storing it on a computer connected to a network such as the Internet and downloading it via the network. Furthermore, the parking assistance program executed in this embodiment may be provided or distributed via a network such as the Internet.

[0080] The above-mentioned embodiments of the present invention do not limit the scope of the invention, but are merely examples of what is included in the scope of the invention. An embodiment of the present invention may also be an embodiment in which at least a portion of the specific uses, structures, shapes, functions, and effects of the above-mentioned embodiments are modified, omitted, or added without departing from the scope of the invention.

[0081] For example, the first reference position is not limited to the front center of the parking area, and can be set at any position on the access road side more than halfway in the parking direction in the parking area.

[0082] In addition, the second reference position is not limited to the position of the driver's seat in the vehicle, and can be set to another position such as the center point of all seats.

[0083] Furthermore, although the image captured by the imaging unit 15 is used to detect parking areas, the present invention is not limited thereto. For example, detection results from the distance measuring units 16 and 17 or LIDAR (Laser Imaging Detection and Ranging) detection results may be used instead of the captured image.

[0084] Alternatively, it is possible to identify whether the relationship between the direction of the passage and the parking direction in the parking area is vertical or inclined, and employ the method of this embodiment only when the relationship is inclined.

Claims

1. A parking assist device comprising: a detection unit for detecting a parking area where parking is possible, i.e., a parking area, among a plurality of parking areas arranged side by side with respect to the passage; a calculation unit for calculating, for each of the parking areas, a distance in the passage direction between a first reference position in the parking area, which is set closer to the passage than halfway in the parking direction, and a second reference position set in the vehicle, when a plurality of the parking areas are detected within a predetermined range and a relationship between the passage direction and the parking direction in the parking areas is identified as being perpendicular or inclined, and when the relationship is identified as being inclined; a selection unit, configured to select the parking area having the shortest distance in the direction of the passage among the plurality of parking areas; as well as The display control unit causes the display unit to highlight the selected parking area. The first reference position is the midpoint of a line at one end of the passageway in the parking area. The second reference position is the position of the driver's seat in the host vehicle.

2. A parking assistance method, comprising: a detection step of detecting a parking area where parking is possible, i.e., a parking area, among a plurality of parking areas arranged side by side with respect to the passage; a calculating step of calculating, when a plurality of the parking areas are detected within a predetermined range, and when a relationship between a direction of the passageway and a parking direction in the parking areas is identified as being perpendicular or inclined, and when the relationship is identified as being inclined, calculating, for each of the parking areas, a distance in the passageway direction between a first reference position in the parking area, which is set closer to the passageway than halfway in the parking direction, and a second reference position set in the vehicle; A selection step of selecting the parking area with the shortest distance in the direction of the access road among the plurality of parking areas; as well as The display control step causes the display unit to highlight the selected parking area. The first reference position is the midpoint of a line at one end of the passageway in the parking area. The second reference position is the position of the driver's seat in the host vehicle.

3. A recording medium storing a parking assistance program, wherein the parking assistance program is configured to cause a computer to execute the following steps: a detection step of detecting a parking area where parking is possible, i.e., a parking area, among a plurality of parking areas arranged side by side with respect to the passage; a calculating step of calculating, when a plurality of the parking areas are detected within a predetermined range, and when a relationship between a direction of the passageway and a parking direction in the parking areas is identified as being perpendicular or inclined, and when the relationship is identified as being inclined, calculating, for each of the parking areas, a distance in the passageway direction between a first reference position in the parking area, which is set closer to the passageway than halfway in the parking direction, and a second reference position set in the vehicle; A selection step of selecting the parking area with the shortest distance in the direction of the access road among the plurality of parking areas; as well as The display control step causes the display unit to highlight the selected parking area. The first reference position is the midpoint of a line at one end of the passageway in the parking area. The second reference position is the position of the driver's seat in the host vehicle.

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