Parking support device

Abstract

To provide a parking support device, which in parking an own vehicle in a parking space utilizing a parking support function, can suppress the possibility that the device wrongly recognizes a position where parking is prohibited as a parking space, even when the device cannot recognize a parking frame drawn on a road surface.SOLUTION: A parking support device 1 comprises an operation support control unit 11. The operation support control unit 11 obtains environment information about a parking lot from sensors 21, 26-28; recognizes a parking space of the parking lot on the basis of the environment information; sets in the parking space a virtual parking frame 41 that is required in parking the own vehicle M; and when marks 51 of shoes are crossing at least two sides of the set virtual parking frame 41, sets the virtual parking frame 41 as a parking prohibition area Anp.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a parking assistance device that suppresses misidentifying a prohibited parking area as a parking space when assisting parking in a parking lot where a parking frame drawn on the road surface cannot be recognized.

Background Art

[0002] Conventionally, there has been known a parking assistance device that assists an operation when a driver parks his / her own vehicle within 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 is operating his / her own vehicle and driving 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 for parking frames.

[0003] Then, the control unit sets a parking guidance route for parking the own vehicle in the parking frame selected by the driver. And the control unit guides the own vehicle to the parking frame along the parking guidance route. Alternatively, the driver operates the own 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 own vehicle in a parking frame, first, an available parking frame is detected. Therefore, when the road surface of the parking lot is covered with snow, crown mud remaining after flooding, or the like 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 route for guiding the own 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 Patent Application Laid-Open No. 2006-7875), first, to determine whether there is a space where the own vehicle can be parked between parked vehicles parked in parallel, the width of each parked vehicle is subtracted from the distance between the centers in the vehicle width direction of the two parked vehicles to obtain the gap distance between the two parked vehicles. If this gap distance is wider than the vehicle width of the own vehicle plus a predetermined margin, it is determined that parking is possible. And a technique is disclosed in which the center of this gap process is set as the center of the planned parking area to guide the own vehicle.

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0007] By the way, when trying to park the own vehicle in a parking lot of a store or the like, since the parking position changes according to the vehicles already parked (parked vehicles), it is difficult to always park in a fixed place. Also, the layout of the parking spaces set in the parking lot differs for each store.

[0008] Therefore, as disclosed in Cited Document 1, even if a gap distance where the own vehicle can be parked between two parked vehicles parked in parallel is detected, in a state where the road surface is covered with snow, crown mud remaining after flooding, etc., since the parking frame drawn on the road surface cannot be recognized, this gap may not be a parking space but a sidewalk where parking is prohibited.

[0009] In the technology disclosed in the above-mentioned Citation Document 1, it merely determines whether the host vehicle can be parked based on the gap distance between adjacent parked vehicles. Therefore, there is a possibility that the control unit may guide the host vehicle to a sidewalk where parking is prohibited, which is set between the parking frames.

[0010] An object of the present invention is to provide a parking support device that can reduce the inconvenience of erroneously guiding the host vehicle to a sidewalk where parking is prohibited even in a situation where a parking frame cannot be recognized when attempting to park the host vehicle in a parking space in a parking lot using a parking support function.

Means for Solving the Problem

[0011] The present invention relates to a parking support device that guides a host vehicle to a parking space in a parking lot, and includes an environmental information acquisition unit that acquires environmental information around the host vehicle, a storage unit that stores information on a virtual parking frame required for parking the host vehicle, a virtual parking frame setting unit that recognizes the parking space in the parking lot based on the environmental information acquired by the environmental information acquisition unit and sets the virtual parking frame stored in the storage unit in the parking space, a footprint detection unit that detects footprints based on the environmental information acquired by the environmental information acquisition unit for the virtual parking frame set by the virtual parking frame setting unit, and a parking area setting unit that sets the virtual parking frame as a non-parking area when the footprint detection unit detects footprints intersecting at least two sides of the virtual parking frame.

Effect of the Invention

[0012] According to the present invention, a virtual parking frame is set in a parking lot recognized based on the environmental information acquired by the environmental information acquisition unit, and when footprints intersect at least two sides of this virtual parking frame, the virtual parking frame is set as a non-parking area. Therefore, when attempting to park the host vehicle in a parking space using a parking support function, even when the parking frame drawn on the road surface cannot be recognized, the possibility of misrecognizing a position where parking is prohibited as a parking space is suppressed, and the discomfort given to the driver can be reduced.

Brief Description of the Drawings

[0013]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5A

Figure 5B

Figure 5C

Figure 6

Figure 7

Figure 8A

Figure 8B

Figure 9A

Figure 9B

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 FIG. 6). 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 non-volatile memory (flash memory or EEPROM), and peripheral devices. Programs and fixed data necessary for the CPU to execute each process are stored in the ROM. 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. Alternatively, a GPU (Graphics Processing Unit) or a GSP (Graph Streaming Processor) may be used instead of the CPU. Or the CPU, GPU, and 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] Based on the vehicle position information acquired by the GNSS sensor 22a of the map locator unit 22 described later, the driving support mode performs map matching on the road map of the road map database 22b and autonomously travels in a section where automatic driving is possible along a preset target travel route. Also, in a driving route where automatic driving is difficult, this driving support mode executes well-known follow - vehicle distance (ACC: Adaptive Cruise Control) control, lane keeping (ALK: Active Lane Keep) control, and lane departure prevention (LDP) control, and when the host vehicle M detects a preceding vehicle while traveling along the lane, it executes a driving control to follow the preceding vehicle.

[0017] On the one hand, in the parking assistance mode, when the host vehicle M enters a parking lot and the driver selects this mode while driving in the parking lot by himself / herself, the driving assistance control unit 11 searches for a parkable parking space in the parking lot and notifies the driver. Then, when the driver selects a desired parking space from among the parkable 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, and parking assistance is provided when the driver parks by his / her own operation.

[0018] In addition, on the input side of the driving assistance 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 assistance mode and the parking assistance mode, are connected.

[0019] In this embodiment, as the sensor units required when executing each assistance mode, a front recognition sensor 21, a map locator unit 22, an autonomous driving sensor 23, a brake sensor 24 that detects the 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 the environmental information behind the host vehicle M, left and right front side sensors 27, and left and right rear side sensors 28 are provided. Note that the environmental information acquisition unit of the present invention is configured by each of the sensors 21, 26 to 28.

[0020] The front recognition sensor 21 is an image sensor. In this embodiment, it is a stereo camera composed of a main camera 21a and a sub-camera 21b, which use a CCD, a CMOS, or the like as an imaging element, and also has 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, for example, and close to the windshield. After 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, it transmits the processed images to the driving assistance control unit 11.

[0021] Furthermore, 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 to acquire 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 the driving assistance mode is executed, and static information of parking lots (position information of entrances and exits to the parking lot, space information within the site, etc.) required when the parking assistance mode is executed.

[0022] The driving assistance control unit 11 performs map matching of the position coordinates (latitude, longitude, altitude) of the host vehicle M acquired by the GNSS sensor 22a on 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 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 configured as a combination of a monocular camera using a CCD, a CMOS, or the like as an imaging device and at least one of an ultrasonic sensor, a millimeter-wave radar, a microwave radar, an infrared sensor, a lidar (Light Detection And Ranging), or the like. Alternatively, the rear sensor 26 may be a stereo camera including 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, at the left and right edge portions of the front bumper of the host vehicle M, and scan a fan-shaped 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, at the left and right edge portions of the rear bumper, and scan a fan-shaped area from the rear of the host vehicle M to the left and right, which cannot be scanned by the left and right front side sensors 27. Each of these side sensors 27 and 28 includes a millimeter-wave radar, a microwave radar, a lidar, or the like, receives a reflected wave from a target (parked vehicle Pv or 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 (parked vehicle Pv or outer wall). Hereinafter, for convenience, the parked vehicle Pv will be described as a representative of the target.

[0026] Further, the driving support control unit 11 is connected to an HMI (Human Machine Interface) monitor 31. On this HMI monitor 31, as a support mode executed by the driving support control unit 11, a mode selection screen for a driver to select either a driving support mode or a parking support mode, a parkable parking space as shown in FIG. 9A, and a screen showing a non-parkable area estimated to be prohibited from parking as shown in FIG. 9B are displayed. Incidentally, this HMI monitor 31 may be shared with a multi-information display of a combination meter or a navigation display device (navigation monitor) of a car navigation system.

[0027] Further, a drive control actuator 32 and a notification device 33 are connected to the output side of the driving support 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., which 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. Further, the notification device 33 notifies the driver of various information required when each support mode is being executed, by voice.

[0028] 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 assists 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 each predetermined calculation cycle after the system is started up.

[0029] In this routine, first, in step S1, the 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 vehicle position is acquired from the map locator unit 22 based on the vehicle position information.

[0030] Next, the process proceeds to step S3, where the 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.

[0031] When proceeding to step S4, the notification device 33 audibly notifies the driver whether to set the assistance mode to the parking assistance mode, and at the same time, a selection screen for the parking assistance mode is displayed on the HMI monitor 31, and the process proceeds to step S5. When proceeding to step S5, it is determined whether the driver has selected the parking assistance mode. If the driving assistance mode is selected, the process proceeds to step S6. Also, if the driver does not select the driving assistance 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.

[0032] When proceeding to step S6, the parking assistance mode is executed and the routine is exited. This parking assistance mode is executed according to the parking assistance mode execution subroutine shown in FIG. 3. In this subroutine, first, in step S11, the forward and front side environment information recognized by the forward recognition sensor 21 and the left and right front side sensors 27 is acquired. Next, the process proceeds to step S12, and it is checked whether a parking frame drawn on the road surface for partitioning the parking space is recognized from the acquired forward and front side environment information. This parking frame is recognized, for example, from the forward and front side environment information acquired by the forward recognition sensor 21 and the left and right front side sensors 27, based on the luminance difference between the road surface and the edge of the parking frame drawn on this road surface, or the change in the intensity (reflectivity) of the reflected light or reflected wave from the road surface and the parking frame.

[0033] And when the driving support control unit 11 determines that the parking frame is recognized, the process proceeds to step S13, and the parking assistance process in a good environment is executed and the routine is exited. Note that this parking assistance process in a good environment is the same as the conventional parking assistance for guiding the own vehicle M to the parking space based on the parking frame, so the description is omitted.

[0034] On the other hand, when it is determined that the parking frame cannot be recognized, that is, the road surface of the parking lot is covered with snow, crown mud remaining after flooding, etc., and thus the parking frame drawn on the road surface cannot be recognized, the process proceeds to step S14, and the parking assistance process in a bad environment is executed and the routine is exited. This parking assistance process in a bad environment is executed according to the parking assistance subroutine in a bad environment shown in FIG. 4.

[0035] In this subroutine, first, in step S21, the virtual parking frame 41 is read. The data (information) 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 it is a frame showing a criterion for checking whether the host vehicle M can be parked in a parking space when parking the host vehicle M in a bad environment. That is, as shown in FIG. 5A, 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 initially by the driver.

[0036] Next, proceed to step S22, and based on the front and front-side environment information obtained from the front recognition sensor 21 or the like of the parking lot where the host vehicle M is traveling, set the virtual parking frame 41 in the space within the parking lot. Note that the processing in this step corresponds to the virtual parking frame setting unit of the present invention.

[0037] As a mode of setting the virtual parking frame 41 in the parking lot, for example, the template image of the virtual parking frame 41 is superimposed on the image of the front and front-side environment information, and it is set while avoiding interference with the recognized image of the parked vehicle Pv. In this case, as shown in FIG. 5B, for example, if the interval Wp between two adjacent parked vehicles Pv is wider than the required parking width Ws of the virtual parking frame 41 (Ws ≧ Wp), the virtual parking frame 41 can be set between the two parked vehicles Pv. On the contrary, as shown in FIG. 5C, if the interval Wp between the two parked vehicles Pv is narrower than the required parking width Ws (Ws < Wp), the virtual parking frame 41 cannot be set.

[0038] At that time, of course, when the intervals between parked vehicles Pv parked along the traffic lane (see FIG. 6) are separated by a predetermined interval (for example, several tens of meters) or more, or when no parked vehicle Pv is parked along the sidewalk, the virtual parking frame 41 is continuously set therebetween.

[0039] By the way, as shown in FIG. 6, when the parking frame drawn on the road surface is hidden by snow accumulation or mud on the road surface, the sidewalk extending in the lateral direction in front of the host vehicle M cannot be recognized from the front and front-side environmental information. Therefore, in the driving support control unit 11, the virtual parking frame 41 is continuously set in the space set as this sidewalk.

[0040] Thereafter, the process proceeds to step S23, and it is checked whether or not footprint 51 is detected in the set virtual parking frame 41. The processing in this step corresponds to the footprint detection unit of the present invention.

[0041] This footprint 51 is, for example, based on the front and front-side environmental information acquired by the front recognition sensor 21 and the left and right front-side sensors 27, the luminance difference generated at the step (edge) with the snow accumulation surface or mud surface derived from the footprint 51, or the change in the intensity of the reflected light or reflected wave (reflectivity). A well-known pattern matching process or the like is performed on a series of feature points indicating the contour of the footprint to recognize the footprint 51.

[0042] If footprint 51 is detected in the virtual parking frame 41, the process proceeds to step S24. If footprint 51 is not detected in the virtual parking frame 41, it is still estimated that no vehicle is parked yet and the possibility of a parking available area is high, and the process jumps to step S28.

[0043] When the process proceeds to step S24, it is checked whether or not parked vehicles Pv are parked on both sides of the virtual parking frame 41. If it is determined that parked vehicles Pv are parked on both sides (see FIG. 7), the process proceeds to step S25. If it is determined that parked vehicles Pv are not parked on both sides (see FIG. 8A) or parked vehicles Pv are parked only on one side (see FIG. 8B), the process branches to step S26.

[0044] When proceeding to step S25, it is examined whether the footprint 51 intersects two sides that do not face the parked vehicle Pv. If the footprint 51 intersects only one side, it is presumed that the footprint 51 was made by a passenger getting in and out of the parked vehicle Pv that previously parked in the parking space, and it is presumed that there is a high possibility of a parking space. On the other hand, as shown in FIG. 7, when the footprint 51 intersects two sides of the virtual parking frame 41, it is highly likely to be a sidewalk. In other words, it is presumed to be a non-parking area with a low possibility of a parking space.

[0045] Therefore, for example, as shown in FIG. 6, when the virtual parking frames 41 are continuously set along this sidewalk at a place that is originally a sidewalk, the footprint 51 intersects at least two sides of each virtual parking frame 41. Therefore, this place is highly likely to be a sidewalk and can be presumed to be a non-parking area.

[0046] Also, when branching to step S26, it is examined whether the footprint 51 intersects at least three sides of the virtual parking frame 41. For example, as shown in FIG. 6, when the virtual parking frame 41 is set at a place where the traffic lane extending in the longitudinal direction in which the host vehicle M is traveling intersects with the sidewalk extending in the lateral direction, since vehicles and pedestrians are moving mixedly in the traffic lane, naturally, the footprint 51 made when the pedestrian moves is also detected on the two sides of the virtual parking frame 41 on the traffic lane side.

[0047] Furthermore, as shown in FIGS. 8A and 8B, when the sidewalk is wider than the virtual parking frame 41, naturally, the footprint 51 is detected outside the virtual parking frame 41. Therefore, when the footprint 51 intersecting at least three sides of the virtual parking frame 41 is detected, this place is highly likely to be a sidewalk and is presumed to be a non-parking area where parking is prohibited.

[0048] Then, if it is estimated as a no-parking area in step S25 or step S26 and proceeds to step S27, the parking priority of the virtual parking frame 41 recognized this time is set low, and it proceeds to step S29. Also, if it branches from any of steps S23, S25, and S26 to step S28, the parking priority of the virtual parking frame 41 recognized this time is set high, and it proceeds to step S29.

[0049] In this case, in the present embodiment, the virtual parking frame 41 with a low parking priority is set as a no-parking area where parking is prohibited, such as a sidewalk, and is temporarily stored in the storage unit. Also, the virtual parking frame 41 with a high parking priority is set as a parking possible area Ps and is temporarily stored in the storage unit. Note that the processing in steps S24 to S28 corresponds to the parking area setting unit of the present invention.

[0050] Then, when proceeding from step S27 or step S28 to step S29, the virtual priority frame 41 associated with the parking priority is displayed by driving the HMI monitor 31 which is the display unit, and it proceeds to step S30. Note that the processing in this step S29 corresponds to the display driving unit of the present invention.

[0051] Display examples of the HMI monitor 31 are shown in FIGS. 9A and 9B. When the host vehicle M approaches the virtual parking frame 41 set by the driving support control unit 11 on the HMI monitor 31, the virtual parking frame 41 corresponding to the parking priority is displayed together with an image indicating the position of the host vehicle M. FIG. 9A shows a mode in which the virtual parking frame 41 with a high parking priority is displayed as the parking possible area Ps. In this case, the parking possible area Ps is highlighted in blue or the like to indicate that parking is possible.

[0052] On the one hand, FIG. 9B shows a state in which a virtual parking space 41 with a low parking priority is displayed. This virtual parking space 41 with a low parking priority is, for example, continuously set on the sidewalk in FIG. 6, and on the HMI monitor 31, it is displayed as a no-parking area Anp in which the continuous virtual parking spaces 41 are integrated horizontally. In this case, this integrally continuous virtual parking space 41 is highlighted in a color such as orange to prompt attention to parking prohibition. The driver can easily recognize whether it is a parking available place or a no-parking place by visually recognizing the parking available area Ps or the no-parking area Anp displayed on the HMI monitor 31.

[0053] Thereafter, when proceeding to step S30, 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 it is determined that the parking support mode is being continued, the process returns to step S22 to recognize the next parking space.

[0054] In this way, in the present embodiment, a virtual parking frame is superimposed on an image of the environmental information acquired in the parking lot. When a footprint 51 intersecting this virtual parking frame 41 is detected, it is estimated that this space is highly likely to be prohibited from parking, and the parking priority is set low. As a result, when attempting to park the host vehicle using the parking support function in a parking space, even if the parking frame drawn on the road surface cannot be recognized, the possibility of misrecognizing a prohibited parking place as a parking space can be suppressed, and the discomfort given to the driver can be reduced. Also, since the no-parking area Anp is displayed on the HMI monitor 31, the driver can easily grasp it visually.

[0055] Furthermore, the present invention is not limited to the above-described embodiments. For example, when the parking available area Ps is displayed on the HMI monitor 31 in step S28 of FIG. 4 described above, the driver selects the parking available area Ps, and the driving support control unit 11 sets the parking available area Ps as the target parking space, and the host vehicle M may be automatically parked in this target parking space. Alternatively, a parking guidance path for guiding the host vehicle M to the target parking space may be superimposed and displayed on the HMI monitor 31 to assist the driver in manually parking.

Explanation of Reference Numerals

[0056] 1…Parking support device, 11…Driving support control unit, 21…Front recognition sensor, 21a…Main camera, 21b…Sub camera, 21c…Image processing unit (IPU), 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, 31…HMI monitor, 32…Drive control actuator, 33…Notification device, 41…Virtual parking frame, 101…Rut, Anp…Non-parking area, M…Host vehicle, Ps…Parking available area, Pv…Parked vehicle, Wp…Interval, 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 information on a virtual parking frame necessary for parking the host vehicle; a virtual parking frame setting unit that sets the virtual parking frame stored in the storage unit in the space of the parking lot based on the environment information acquired by the environment information acquisition unit; a footprint detection unit that checks whether footprints recognized based on the environment information acquired by the environment information acquisition unit are detected within the virtual parking frame set by the virtual parking frame setting unit; a parking area setting unit that sets the virtual parking frame as a non-parkable area when the footprint detection unit detects footprints intersecting at least two sides of the virtual parking frame A parking assistance device characterized by comprising:

2. further comprising an object detection unit that detects an object in the parking lot based on the environment information acquired by the environment information acquisition unit, wherein the parking area setting unit sets the virtual parking frame as a non-parkable area when there are the objects detected by the object detection unit adjacent to both sides of the virtual parking frame and further when footprints intersecting two sides not facing the objects are detected. The parking assistance device according to claim 1, characterized in that.

3. a display driving unit that causes a display unit to display the non-parkable area when the parking area setting unit sets the virtual parking frame as the non-parkable area The parking assistance device according to claim 1 or 2, further comprising:

4. The parking area setting unit sets the virtual parking frame as a parkable area when the footprint detection unit detects footprints intersecting only one side of the virtual parking frame or when no footprints are detected in the virtual parking frame. The parking assistance device according to claim 1 or 2, characterized in that.

5. a display driving unit that causes a display unit to display the parkable area when the parking area setting unit sets the virtual parking frame as the parkable area The parking assistance device according to claim 4, further comprising:

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