Parking assistance device

Abstract

To provide a parking support device, which in parking an own vehicle in a parking space utilizing a parking support function, can detect a parking space in which the own vehicle can be parked and guide the vehicle to the space, even when the device cannot recognize a parking frame.SOLUTION: A parking support device 1 comprises an operation support control unit 11. The operation support control unit 11 obtains environment information about a circumference of an own vehicle M from sensors 21, 26-29, determines a parking space width Wp between parked vehicles Pv parked in a parking lot on the basis of the environment information, and compares the parking space width Wp with a required parking width Ws of a virtual parking frame 41 that is required in parking the own vehicle M, which when the parking space width Wp is larger than the required parking width Ws, sets the virtual parking frame 41 in the parking space and guides the own vehicle M to the virtual parking frame 41.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a parking assistance device that can smoothly park a vehicle even in a parking lot where a parking frame drawn on the road surface cannot be recognized.

Background Art

[0002] Conventionally, a parking assistance device is known that assists an operation when a driver parks a vehicle in a parking frame that demarcates a parking space set in a parking lot, thereby reducing the driver's burden. In this type of parking assistance device, when the driver operates the vehicle to drive within the parking lot, the control unit detects candidates for available parking frames and displays the parking frames listed as candidates on a monitor. The driver selects a desired parking frame from the displayed candidates.

[0003] Then, the control unit sets a parking guidance route for parking the vehicle in the parking frame selected by the driver. And the control unit guides the vehicle along the parking guidance route to the parking frame. Alternatively, the driver operates the vehicle and parks it in the parking frame along the parking guidance route displayed on the monitor.

[0004] In the above-described conventional parking assistance device, when parking the vehicle in a parking frame, first, available parking frames are detected. Therefore, when the road surface of the parking lot is covered with snow, puddle mud remaining after flooding, etc., and the parking frame drawn on the road surface cannot be recognized, it becomes difficult for the parking assistance device to construct a parking guidance path for guiding the vehicle to the parking frame.

[0005] Drivers need parking assistance by a parking assistance device more in a bad environment where it is difficult to recognize a parking space than in a good environment. For example, in Patent Document 1 (Japanese Unexamined Patent Application Publication No. 2021-3926), when the parking space in a parking lot cannot be recognized due to snow accumulation, first, information on a pair of ruts determined to be driving tracks engraved on the snow accumulation is acquired, and a position where the ruts are interrupted in the parking space direction is set as the stop position of the tires of the own vehicle at the time of parking. Then, a target parking guidance path for guiding the own vehicle along the pair of ruts up to this stop position is set.

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0007] However, in the technology disclosed in Patent Document 1, when the parking assistance device cannot detect a pair of ruts engraved on the snow accumulation, even if the driver visually recognizes an empty parking space, the parking assistance control does not function, which will give discomfort to the driver.

[0008] That is, when the driver tries to park the own vehicle in a parking lot of a store, especially in a situation where the parking lot has a bad environmental surface due to snow accumulation, mud on the road surface, etc., the driver tries to park in a parking space as close to the store as possible. Therefore, a plurality of vehicles enter and exit an empty parking space close to the store, and naturally, a plurality of types of ruts are engraved.

[0009] When the driver tries to park the own vehicle in a parking space using the parking assistance function in such an environment, the parking assistance device will select a parking space with a pair of ruts engraved far from the store, which will cause inconvenience to the passengers including the driver.

[0010] When attempting to park the host vehicle in a parking space using a parking assistance function, the present invention aims to provide a parking assistance device that can detect a parkable parking space even when it is unable to recognize a parking frame, and moreover, even if there are multiple types of tire tracks indicating entry and exit to / from the available parking space, or no tire tracks at all.

Means for Solving the Problem

[0011] The present invention relates to a parking assistance device that guides a host vehicle into a parking space in a parking lot, comprising: an environmental information acquisition unit that acquires environmental information around the host vehicle; a storage unit that stores a virtual parking frame necessary for parking the host vehicle; a parking interval calculation unit that determines the width of the parking space based on the environmental information acquired by the environmental information acquisition unit; a parking width comparison unit that compares the width of the parking space determined by the parking interval calculation unit with the width of the virtual parking frame stored in the storage unit; a virtual parking frame setting unit that sets the virtual parking frame within the parking space when it is determined by the parking width comparison unit that the width of the parking space is wider than the width of the virtual parking frame; a parking space determination unit that checks, based on the environmental information acquired by the environmental information acquisition unit, whether an object faces the three sides of the virtual parking frame excluding the side on the host vehicle side of the virtual parking frame set by the virtual parking frame setting unit; a parkable space setting unit that sets the virtual parking frame as a parkable space in which the host vehicle can park when it is determined by the parking space determination unit that the object faces the three sides; and a parking assistance unit that guides the host vehicle to the parkable space set by the parkable space setting unit. The parking space determination unit includes a rut detection unit that detects ruts within the virtual parking frame based on the environmental information acquired by the environmental information acquisition unit. When the parking space setting unit determines that the target does not face at least one of the three sides of the virtual parking frame excluding the side on the host vehicle side of the virtual parking frame, and the rut detection unit detects a rut that intersects two sides of the virtual parking frame that the target does not face, the virtual parking frame is cleared. .

Advantages of the Invention

[0012] According to the present invention, when attempting to guide a host vehicle to a parking space in a parking lot, first, the width of the parking space obtained based on the environmental information acquired by the environmental information acquisition unit is compared with the width of a virtual parking frame required for parking the host vehicle, which is stored in advance. When it is determined that the width of the parking space is wider than the width of the virtual parking frame, a virtual parking frame is set within this parking space, and it is checked whether an object faces three sides excluding the side of the virtual parking frame on the host vehicle side. When an object faces the three sides, this virtual parking frame is set as a parkable space where the host vehicle can park, and the host vehicle is guided to this parkable space. Therefore, even if the virtual parking frame cannot be recognized, and there are multiple types of ruts inscribed for entering and exiting the vacant parking space, or even if there are no ruts at all, a parkable parking space can be detected and the vehicle can be guided to it.

Brief Description of the Drawings

[0013]

Figure 1

Figure 2

Figure 3

Figure 4

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Figure 6A

Figure 6B

Figure 6C

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Mode for Carrying Out the Invention

[0014] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. The parking support device 1 shown in FIG. 1 is mounted on the host vehicle M (see FIGS. 7 and 9). This parking support device 1 includes a driving support control unit 11. This driving support control unit 11 is composed of a microcontroller including a CPU, a RAM, a ROM, a rewritable nonvolatile memory (flash memory or EEPROM), and peripheral devices. The ROM stores programs and fixed data necessary for the CPU to execute each process. The RAM is provided as a work area for the CPU, and various data in the CPU are temporarily stored. Note that the CPU is also called an MPU (Microprocessor) or a processor. Instead of the CPU, a GPU (Graphics Processing Unit) or a GSP (Graph Streaming Processor) may be used. Alternatively, the CPU, the GPU, and the GSP may be selectively combined and used.

[0015] When the driver sets a desired support mode, this driving support control unit 11 performs driving support according to the corresponding support mode. The driving support control unit 11 includes a driving support mode and a parking support mode as support modes.

[0016] The driving support mode performs map matching on the road map of the road map database 22b based on the vehicle position information acquired by the GNSS sensor 22a of the map locator unit 22 described later, and autonomously drives the vehicle in a section where autonomous driving is possible along a preset target driving route. Also, in a driving route where autonomous driving is difficult, this driving support mode executes well-known following distance (ACC: Adaptive Cruise Control) control, lane keeping (ALK: Active Lane Keep) control, and lane departure prevention (LDP) control. When the host vehicle M is detected following the lane and the preceding vehicle, the driving support mode executes driving control to follow the preceding vehicle.

[0017] On the other hand, when the host vehicle M enters a parking lot and the driver selects this mode while driving in the parking lot, the parking support mode causes the driving support control unit 11 to search for a parking space where parking is possible and notify the driver. Then, when the driver selects a desired parking space from the available parking spaces, the host vehicle M is automatically parked in the selected parking space. Alternatively, a parking guidance route for parking the host vehicle in the parking space is superimposed on an overhead view of the surrounding image displayed on the HMI monitor 31 described later and the image of the host vehicle M to provide parking support when the driver parks by their own operation.

[0018] Also, on the input side of the driving support control unit 11, sensor units for acquiring the driving state information (including position and direction) of the host vehicle M and the surrounding environment information of the host vehicle M, which are required when executing the driving support mode and the parking support mode, are connected.

[0019] As sensor units required when executing each support mode, in the present embodiment, a front recognition sensor 21, a map locator unit 22, an autonomous driving sensor 23, a brake sensor 24 that detects depression of the brake pedal and turns on, a select position sensor 25 that detects the select position selected by the driver operating the select lever, a rear sensor 26 that acquires environmental information behind the host vehicle M, left and right front side sensors 27, left and right rear side sensors 28, and left and right front side recognition cameras 29 are provided. Note that the environmental information acquisition unit of the present invention is configured by the sensors 21, 26 to 29.

[0020] The front recognition sensor 21 is an image sensor, and in the present embodiment, it is a stereo camera including a main camera 21a and a sub camera 21b using a CCD, a CMOS, or the like as an imaging element, and an image processing unit (IPU) 21c. Both cameras 21a and 21b have a predetermined baseline length and are installed horizontally at equal intervals on the left and right from the center in the vehicle width direction at a position above the rearview mirror at the front of the vehicle interior and close to the windshield. The front recognition sensor 21 processes the images of the environmental information in a predetermined area captured by both cameras 21a and 21b with the IPU 21c and then transmits them to the driving support control unit 11.

[0021] Further, the map locator unit 22 includes a GNSS (Global Navigation Satellite System) sensor 22a and a road map database 22b. The GNSS sensor 22a receives positioning signals transmitted from a plurality of positioning satellites and acquires the position coordinates of the host vehicle M. The road map database 22b is a large-capacity storage medium such as an HDD and stores road map information. The road map information stored in this road map database 22b includes road information (general roads, arterial roads, highways, road shapes, road orientations, number of lanes, lane widths, etc.) required when executing the driving support mode, and static information of parking lots (position information of entrances and exits to the parking lot, site information, etc.) required when executing the parking support mode.

[0022] The driving support control unit 11 performs map matching of the position coordinates (latitude, longitude, altitude) of the host vehicle M acquired by the GNSS sensor 22a onto the road map information stored in the road map database 22b to estimate the position of the host vehicle (current position) on the road map.

[0023] The autonomous driving sensor 23 is a general term for the sensors required when the host vehicle M is autonomously driven, and is composed of a vehicle speed sensor that detects the vehicle speed (host vehicle speed) of the host vehicle M, a yaw rate sensor that detects the yaw rate acting on the host vehicle M, a longitudinal and lateral acceleration sensor that detects the longitudinal and lateral accelerations, and the like.

[0024] Further, the rear sensor 26 is composed of a combination of at least one of a monocular camera using a CCD, a CMOS, etc. as an imaging element and an ultrasonic sensor, a millimeter-wave radar, a microwave radar, an infrared sensor, a lidar, a LiDAR (Light Detection And Ranging), etc. Alternatively, the rear sensor 26 may be a stereo camera composed of a main camera and a sub-camera, similar to the above-described front recognition sensor 21.

[0025] Further, the left and right front side sensors 27 are respectively disposed, for example, on the left and right edge portions of the front bumper of the host vehicle M, and scan in a fan shape the area (scanning area) from the left and right diagonally forward to the side of the host vehicle M. On the other hand, the left and right rear side sensors 28 are disposed, for example, on the left and right edge portions of the rear bumper, and scan in a fan shape the area from the rear of the host vehicle M to the left and right that cannot be scanned by the left and right front side sensors 27. Each of these side sensors 27, 28 is composed of a millimeter-wave radar, a microwave radar, a LiDAR, etc., receives the reflected wave from a target (a parked vehicle Pv or an outer wall in the parking support mode), and acquires environmental information such as the distance and azimuth from the host vehicle M to the target (a parked vehicle Pv or an outer wall).

[0026] Furthermore, the left and right front side recognition cameras 29 are mounted near the left and right side mirrors, and recognize the presence or absence of parking frame lines on the side of the host vehicle M that cannot be covered by the viewing angle of the front recognition sensor 21, the presence or absence of ruts, the presence or absence of footprints, etc. The left and right front side recognition cameras 29 are equipped with image sensors such as CCDs and CMOSs, and an image processing unit. After the image of the front side environment information captured by the image sensor is processed by the image processing unit, it is transmitted to the driving assistance control unit 11.

[0027] In addition, the driving assistance control unit 11 is connected to an HMI (Human Machine Interface) monitor 31. On this HMI monitor 31, as assistance modes executed by the driving assistance control unit 11, there are a mode selection screen for the driver to select either a driving assistance mode or a parking assistance mode, a parking space selection screen (see Fig. 8) for displaying a parkable parking space and allowing the driver to select it, etc. are displayed. Incidentally, this HMI monitor 31 may be used in combination with a multi-information display of a combination meter or a navigation display device (navigation monitor) of a car navigation system.

[0028] In addition, a drive control actuator 32 and a notification device 33 are connected to the output side of this driving assistance control unit 11. This drive control actuator 32 is a general term for a power actuator, an electric power steering (EPS) actuator, a brake actuator, etc. that assist the running state of the host vehicle M. Here, the power actuator controls the output of a drive source such as an engine or an electric motor. The EPS actuator controls the drive of the EPS motor. Also, the brake actuator adjusts the brake hydraulic pressure supplied to the brake wheel cylinders provided on each wheel. Furthermore, the notification device 33 audibly notifies the driver of various information required when each assistance mode is being executed.

[0029] The driving support control unit 11 has a parking support control function that parks the host vehicle M in a parking space on behalf of the driver or supports the driver when the driver attempts to park the host vehicle M in a parking space by their own driving. The parking support control executed by the driving support control unit 11 is specifically processed according to the parking support control routine shown in FIG. 2. This routine is executed at a predetermined calculation cycle after the system is started.

[0030] In this routine, first, in step S1, the host vehicle position information estimated by the map locator unit 22 is acquired, and the process proceeds to step S2, where the surrounding map information of the host vehicle position is acquired from the map locator unit 22 based on the host vehicle position information.

[0031] Next, the process proceeds to step S3, where the host vehicle position is map-matched to the surrounding map to check whether the host vehicle M has entered the parking lot. If it is determined that the vehicle has entered the parking lot, the process proceeds to step S4. If it is determined that the vehicle has not entered the parking lot, the routine is exited.

[0032] When the process proceeds to step S4, the notification device 33 audibly notifies the driver of an announcement asking whether to set the support mode to the parking support mode, and a selection screen for the parking support mode is displayed on the HMI monitor 31, and the process proceeds to step S5. When the process proceeds to step S5, it is determined whether the driver has selected the parking support mode. If the driving support mode is selected, the process proceeds to step S6. If the driver does not select the driving support mode even after a predetermined time has elapsed after the announcement, or if the driver selects manual driving on the HMI monitor 31, the routine is exited as it is.

[0033] When the process proceeds to step S6, the parking support mode is executed and the routine is exited. This parking support mode is executed according to the parking support mode execution subroutine shown in FIG. 3. In this subroutine, first, in step S11, the front and front side environment information recognized by the front recognition sensor 21, the left and right front side sensors 27, and the left and right front side recognition cameras 29 is acquired.

[0034] Next, proceed to step S12, and detect parked vehicles (parked vehicle) Pv parked on the left and right sides of the traffic lane from the acquired front and front-side environmental information. That is, as shown in FIG. 7, while the host vehicle M is traveling at a low speed in the traffic lane, parked vehicles (parked vehicle) Pv parked in parallel on the left and right sides of the traffic lane are detected based on the acquired front and front-side environmental information.

[0035] Thereafter, proceed to step S13, and check whether there is a parking space next to the detected parked vehicle Pv. This parking space is a space for normal parking having a predetermined parking width partitioned by a parking frame described later, and is a fixed value set in advance. If no parking space is detected, branch to step S14, and if a parking space is detected, proceed to step S15.

[0036] When branching to step S14, check whether the parking support mode has ended. If it is determined that it has ended, exit the routine. On the other hand, if the parking support mode is continued, return to step S11 and repeat the processes of steps S11 to S13. The end of the parking support mode is performed by an operation of the driver via the HMI monitor 31 or the like. Alternatively, this parking support mode is automatically terminated when the driving support control unit 11 detects the host vehicle M exiting the parking lot.

[0037] On the other hand, when proceeding from step S13 to step S15, check whether a parking frame drawn on the road surface for partitioning the parking space is recognized. This parking frame is recognized, for example, from the front and front-side environmental information acquired by the front recognition sensor 21, the left and right front-side sensors 27, and the left and right front-side recognition cameras 29, based on the luminance difference between the road surface and the edge of the parking frame, or the change in the intensity (reflectivity) of the reflected light or reflected wave from the road surface and the parking frame.

[0038] If the driving support control unit 11 determines that the parking frame is recognized, proceed to step S16, execute the parking support process in a favorable environment, and exit the routine. Note that this parking support process in a favorable environment is the same as the conventional parking support for guiding the host vehicle M to the parking space based on the parking frame, and thus the description is omitted.

[0039] On the other hand, if it is determined that the parking space cannot be recognized, that is, the road surface of the parking lot is covered with snow, crown mud left after flooding, etc., and the parking space marked on the road surface cannot be recognized, the process proceeds to step S17, and the parking support process in a bad environment is executed to exit the routine. This parking support process in a bad environment is executed according to the parking support subroutine shown in FIGS. 4 to 5.

[0040] In this subroutine, first, in step S21, the virtual parking frame 41 is read. The data of this virtual parking frame 41 is pre-stored as fixed data in a storage unit such as a ROM or a non-volatile memory, and is a frame indicating a criterion for examining whether the host vehicle M can be parked in the parking space when parking the host vehicle M in a bad environment. That is, as shown in FIG. 6A, this virtual parking frame 41 is set as a rectangle with four sides orthogonal to each other, the front-rear direction is set to the front-rear length of the host vehicle M, and the left and right have a required parking width Ws obtained by adding a margin width to the vehicle width of the host vehicle M. Note that this required parking width Ws may be arbitrarily set by the driver in an initial setting.

[0041] Next, when proceeding to step S22, the interval (parking space width) Wp of the parking space adjacent to the detected parked vehicle Pv is calculated. This parking space width Wp is based on the front and front-side environment information obtained by the front recognition sensor 21, the left and right front-side sensors 27, and the left and right front-side recognition cameras 29, and recognizes the vehicles (parked vehicles) Pv parked in the parallel direction (see FIGS. 7 and 9) and object targets such as outer walls, and obtains the widths of the recognized object targets (parked vehicle Pv, outer wall) and the front distance from the object target to the host vehicle M, and obtains the interval (parking space width Wp) between adjacent object targets from this data. Note that the process in this step S22 corresponds to the parking interval calculation unit of the present invention.

[0042] Thereafter, the process proceeds to step S23, where the parking space width Wp and the required parking width Ws are compared. If Wp ≥ Ws, it is determined that the space is sufficient for parking the host vehicle M, and the process proceeds to step S24. If Wp < Ws, it is determined that it is difficult to park the host vehicle M, and the process jumps to step S30. Note that the processing in this step S23 corresponds to the parking width comparison unit of the present invention.

[0043] Next, the process proceeds to step S24, where a virtual parking frame 41 is set in the detected parking space, and the process proceeds to step S25. The center of the width direction of the virtual parking frame 41 is set at the center of the width direction of the parking space, and the side of the virtual parking frame 41 on the host vehicle M side is set on the same plane as the tip of the object in front. At this time, for example, when the distance between the objects (Wp) is twice or more the required parking width Ws, a number of virtual parking frames 41 that fit within the space are set at equal intervals. Also, if the space between the adjacent parked vehicles Pv is wide and three or more virtual parking frames 41 can be set, since the parking space is too wide, the virtual parking frame 41 may not be selected and the process may jump to step S30. Note that the processing in this step S24 corresponds to the virtual parking frame setting unit of the present invention.

[0044] When the process proceeds to step S25, it is checked based on the front and front-side environmental information whether objects (parked vehicles Pv or outer walls) that are relatively close are facing the three sides other than the side 41a on the host vehicle M side of the virtual parking frame 41 (the side not facing the object). If objects are facing the three sides (see FIG. 10), the process jumps to step S28. If there is a side 41a where no object is facing at least one of the three sides of the virtual parking frame 41 (see FIGS. 11 and 12), the process proceeds to step S26. In FIGS. 10 to 12, the side 41a where no object is facing is shown by a solid line, and the side 41b where an object is facing is shown by a dashed line.

[0045] As shown in FIG. 10, three parked vehicles Pv as targets face three sides of the virtual parking frame 41 other than the side 41a on the own vehicle M side. In this case, since only the side 41a does not face the parked vehicle Pv of the virtual parking frame 41, it can be estimated that this virtual parking frame 41 is highly likely to be a parking space. The same applies even if only the parked vehicle Pv on the back side is the outer wall.

[0046] On the other hand, in FIG. 11, the parked vehicle Pv as a target is parked in parallel on both sides of the virtual parking frame 41. Therefore, the two opposing sides 41a shown by solid lines become the sides 41a that do not face the two parked vehicles Pv. Also, in FIG. 12, one of the parked vehicles Pv as a target is parked in parallel next to the virtual parking frame 41, and the other parked vehicle Pv is parked at the back. Therefore, the two adjacent sides 41a shown by solid lines become the sides 41a that do not face the two parked vehicles Pv.

[0047] When proceeding to step S26, road surface information focused on the virtual parking frame 41 set in the parking space is acquired from the forward and front-side environment information recognized by the forward recognition sensor 21, the left and right front-side sensors 27, and the left and right front-side recognition cameras 29, and it is examined whether there is a rut 101 in the virtual parking frame 41 from this road surface information. The rut 101 is recognized, for example, based on the road surface information, by performing well-known pattern matching processing or the like on a series of feature points indicating the edge of the rut from the luminance difference generated at the step (edge) with the snow-covered surface or the mud-covered surface derived from the rut 101, or the change in the intensity of the reflected light or the reflected wave (reflectivity).

[0048] If it is determined that there is a rut 101, proceed to step S27. If the rut 101 is not detected, it is estimated that the inside of this virtual parking frame 41 is a parking space and jump to step S28. Note that the processing in this step S26 corresponds to the rut detection unit of the present invention.

[0049] When proceeding to step S27, it is examined whether the rut 101 intersects the two sides 41a including the entrance / exit that the parked vehicle Pv is not facing, based on the forward and front-side environmental information. Note that the rut 101 is determined by extracting the snow-covered surface, mud-covered surface, and steps (edges) derived from the rut 101 based on the forward and front-side environmental information. Also, the processes in steps S25 to S27 correspond to the parking space determination unit of the present invention.

[0050] If no intersecting rut 101 is detected, proceed to step S29. If a rut 101 intersecting the two sides is detected, it is estimated that the space where the virtual parking frame 41 is set is highly likely to be a traffic lane, proceed to step S28, clear the virtual parking frame 41 set in the parking space, and jump to step S30.

[0051] If the rut 101 intersects only one of the two sides 41a that the parked vehicle Pv is not facing, that is, only the side 41a on the host vehicle M side, and the end of the rut 101 is cut within the virtual parking frame 41 (see Fig. 10), it can be estimated that it is highly likely to be a tire mark for parking. On the other hand, as shown in Figs. 11 and 12, if a rut 101 intersecting (crossing) the two sides 41a that the parked vehicle Pv is not facing of the virtual parking frame 41 is detected, it can be estimated that this is not a parking space but is highly likely to be a traffic lane.

[0052] After that, when proceeding from any of steps S25 to S27 to step S29, the current virtual parking frame 41 is set as the parking available space Ps, and proceed to step S30. Note that the processes in steps S28 and S29 correspond to the parking available space setting unit of the present invention.

[0053] When proceeding from any of steps S23, S28, and S29 to step S30, it is examined whether the detection of all parking available space candidates based on the currently acquired forward and front-side environmental information is completed. If not yet completed, return to step S12 in Fig. 3 to detect the next parked vehicle Pv in order to search for the next candidate for the parking available space. If all candidates for the parking available space are detected, proceed to step S31.

[0054] In step S31, the parking space Ps detected this time is displayed on the HMI monitor 31. FIG. 8 illustrates the parking space Ps displayed on the HMI monitor 31. As shown by hatching in FIG. 7, when the virtual parking frames 41 set at two locations, the front side and the back side of the traffic lane, are set as the parking space Ps, the set parking space Ps is displayed in a bird's-eye view on the HMI monitor 31.

[0055] Next, proceed to step S32, drive the notification device 33, and make an announcement to the driver asking which of the parking spaces Ps (two locations in FIG. 8) displayed on the HMI monitor 31 to select. Then, proceed to step S33 and determine whether the driver has selected any of the parking spaces. For example, as shown in FIG. 8, when the driver hopes to automatically park in the parking space Ps on the side closer to the store, touch the upper parking space Ps displayed on the HMI monitor 31.

[0056] If it is determined in step S33 that the driver has selected any of the parking spaces Ps, proceed to step S34. Also, if a predetermined time has elapsed after the announcement or the host vehicle M has passed in front of the parking space displayed on the HMI monitor 31, it branches to step S35. Note that the processing in this step S33 corresponds to the parking space selection unit of the present invention.

[0057] When branching to step S35, if the driver has not selected any of the parking spaces even after a predetermined time has elapsed, the driving support control unit 11 clears all the displayed parking spaces, or if the host vehicle M has passed in front of the corresponding parking space, clears the display of the parking space and proceeds to step S37.

[0058] In step S37, it is checked whether the parking support mode has ended. If it is determined that it has ended, the routine is exited. On the other hand, if the parking support mode is continuing, the process returns to step S11 in FIG. 3, and based on the newly acquired forward and front-side environmental information, the next parking vehicle Pv is detected. Note that the end of the parking support mode is the same as the process in step S14 shown in FIG. 3 described above.

[0059] On the other hand, when proceeding from step S33 to step S34, the driving support control unit 11 sets the parking available space Ps (upper side in FIG. 8) selected by the driver as the current target parking space Pt (see FIG. 8), and proceeds to step S36. In step S36, control is executed to automatically park the host vehicle M in the target parking space Pt, and the routine ends. Note that the processes in steps S34 and S36 correspond to the parking support unit of the present invention.

[0060] That is, in the automatic parking support by the driving support control unit 11 in steps S34 and S37, first, as shown in FIG. 9, a target parking guidance path Gr for guiding the host vehicle M to the target parking space Pt is set. This target parking guidance path Gr is set such that the center in the vehicle width direction of the host vehicle M coincides with the center in the width direction of the target parking space Pt. Alternatively, for example, when the parking space width Wp between targets (parking vehicles Pv) is a predetermined value or more (for example, 1.5 times) with respect to the required parking width Ws of the target parking space Pt of the host vehicle M, the end of the required parking width Ws on the driver's seat side of the host vehicle M is moved closer to the adjacent target (parking vehicle Pv) side, and the target parking space Pt is set. Then, the target parking guidance path Gr may be set so as to park the center in the width direction of the host vehicle M at the center in the width direction of this target parking space Pt.

[0061] Thereafter, after the driving support control unit 11 automatically parks the host vehicle M in the target parking space Pt at a predetermined position, the routine is exited. Note that this target parking guidance path Gr is set in accordance with the normal target parking guidance path set when a parking frame is recognized.

[0062] As a result, for example, as shown in FIG. 9, by having the host vehicle M circle around the traffic lane in the parking lot, it is possible to acquire the position information of all the parked vehicles Pv parked in the parking lot. In this case, similar to FIG. 8 described above, the positions of all the parked vehicles Pv parked in the parking lot and the available parking spaces Ps indicated by hatching in the figure are displayed in a bird's-eye view on the HMI monitor 31 so that the driver can select a desired available parking space Ps.

[0063] As described above, in this embodiment, when attempting to automatically park the host vehicle in a parking space in the parking lot, first, it is checked whether there is a parking space for parking the host vehicle M next to the parked vehicle Pv. If a parking space is detected, it is then checked whether a parking frame that demarcates the parking space is recognized in the parking space. And when the parking frame is covered by snow accumulation, mud, etc. and cannot be recognized, parking support processing in a harsh environment is executed.

[0064] In the parking support processing in a harsh environment, the width Wp of the parking space next to the parked vehicle Pv is calculated, and this parking space width Wp is compared with the required parking width Ws of the virtual parking frame 41 set for the host vehicle M. And when Wp ≥ Ws and there are targets facing three sides of the virtual parking frame 41, the virtual parking frame 41 is set as the available parking space Ps. Thereby, when attempting to park the host vehicle using the parking support function in the parking space, even when the parking frame cannot be recognized, and moreover, there are multiple types of ruts engraved for entering and exiting the empty parking space, or even if there are no ruts engraved at all, it is possible to easily detect an available parking space.

[0065] Also, when there are two sides of the virtual parking frame 41 that are not facing a target and there are ruts intersecting on these two sides, it is presumed that the virtual parking frame 41 is set in the traffic lane, and the available parking space Ps is not set for the virtual parking frame 41, so that the host vehicle M is not accidentally parked in the traffic lane.

[0066] Furthermore, the present invention is not limited to the above-described embodiments. For example, in a parking lot, the driver manually operates the own vehicle M to drive around and searches for a parking space where the virtual parking frame 41 fits while visually recognizing the HMI monitor 31. Then, when the driver identifies a parking space where the virtual parking frame 41 fits, the own vehicle M is temporarily stopped before that, and a driving support mode is selected. Thereby, the driving support control unit 11 may check whether the own vehicle M can be parked in the identified parking space, and execute driving support when it is determined that parking is possible.

[0067] Also, for example, in the process of step S36 described above, a target parking guidance path Gr may be superimposed and displayed on the HMI monitor 31 in an overhead view around the parking space where parking is to be performed, and the driver may park the own vehicle M along the target parking guidance path Gr by his / her own driving.

Explanation of Reference Numerals

[0068] 1… Parking support device, 11… Driving support control unit, 21… Front recognition sensor, 21a… Main camera, 21b… Sub camera, 22… Map locator unit, 22a… GNSS sensor, 22b… Road map database, 23… Autonomous driving sensor, 24… Brake sensor, 25… Select position sensor, 26… Rear sensor, 27… Left and right front side sensors, 28… Left and right rear side sensors, 29… Left and right front side recognition cameras, 31… HMI monitor, 32… Drive control actuator, 33… Notification device, 41… Virtual parking frame, 41a… Side not facing the target, 41b… Side facing the target 101… Track, Gr…Target parking guidance road, M…Own vehicle, Ps…Parking available space, Pt…Target parking space, Pv…Target (parked vehicle), Wp…Parking space width, Ws…Required parking width

Claims

1. In a parking assistance device that guides a host vehicle to a parking space in a parking lot, an environment information acquisition unit that acquires environment information around the host vehicle; a storage unit that stores a virtual parking frame necessary for parking the host vehicle; a parking interval calculation unit that obtains the width of the parking space based on the environment information acquired by the environment information acquisition unit; a parking width comparison unit that compares the width of the parking space obtained by the parking interval calculation unit with the width of the virtual parking frame stored in the storage unit; a virtual parking frame setting unit that sets the virtual parking frame within the parking space when it is determined by the parking width comparison unit that the width of the parking space is wider than the width of the virtual parking frame; a parking space determination unit that examines whether or not a target object faces three sides excluding the side on the host vehicle side of the virtual parking frame set by the virtual parking frame setting unit, based on the environment information acquired by the environment information acquisition unit; a parkable space setting unit that sets the virtual parking frame as a parkable space in which the host vehicle can park when it is determined by the parking space determination unit that the target object faces the three sides; a parking assistance unit that guides the host vehicle to the parkable space set by the parkable space setting unit and comprising: The parking space determination unit has a rut detection unit that detects a rut within the virtual parking frame based on the environment information acquired by the environment information acquisition unit, When the parkable space setting unit determines that the target object does not face at least one of the three sides excluding the side on the host vehicle side of the virtual parking frame, and the rut detection unit detects a rut that intersects two sides of the virtual parking frame where the target object does not face, the virtual parking frame is cleared. A parking assistance device characterized by the above.

2. The two sides that do not face the target object are the side on the host vehicle side and the side opposite to the side on the host vehicle side, or the side on the host vehicle side and the side adjacent to the side on the host vehicle side. The parking assistance device according to claim 1, characterized by the above.

3. When the parkable space setting unit sets a plurality of parkable spaces, it further has a parking space selection unit that allows a driver to select one of the parkable spaces, The parking assistance unit guides the host vehicle to the parkable space selected by the parking space selection unit. The parking assistance device according to claim 1, characterized by the above.

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