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 suppress the possibility that the device wrongly recognizes a position where parking is prohibited as a parking space, even in a situation where 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 wheel tracks 101 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 prevents a place where parking is prohibited from being mistakenly recognized as a parking space when providing parking assistance in a parking lot where a parking frame drawn on the road surface cannot be recognized. [Background technology]

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

[0003] Then, the control unit sets a parking guide route for parking the vehicle in the parking space selected by the driver. Then, the control unit automatically parks the vehicle in the parking space along the parking guide route. Alternatively, the driver drives the vehicle along the parking guide route displayed on the monitor and parks it in the parking space.

[0004] In the above-mentioned conventional parking assistance device, when the vehicle is parked in a parking space, first, detects a parking space that can be parked.Therefore, when the road surface of the parking lot is covered with snow or mud remaining after flooding, and the parking space drawn on the road surface cannot be recognized, it is difficult for the parking assistance device to construct a parking guide route that leads the vehicle to the parking space.

[0005] A driver needs parking assistance from a parking assistance device more in a bad environment where a parking space cannot be recognized than in a good environment. For example, in Patent Document 1 (JP 2021-3926 A), when a parking space in a parking lot cannot be recognized due to snowfall, first, information on a pair of ruts that are determined to be a driving trajectory engraved on the snow is acquired, and the position where the ruts end in the direction of the parking space is set as the stopping position of the vehicle's tires when parking. Then, a technology is disclosed in which a target parking guidance route is set to guide the vehicle along the pair of ruts to this stopping position. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Patent Publication No. 2021-3926 Summary of the Invention [Problem to be solved by the invention]

[0007] In this type of parking assistance control, first, available parking spaces (parking positions) are displayed on a monitor, and when the driver selects a parking position displayed, a parking guidance route for parking the vehicle at the parking position is generated and superimposed on the monitor. If this is applied to the technology disclosed in the above-mentioned document, when a pair of wheel tracks is detected in a parking lot, the space is set as a target parking position and displayed on the monitor, and the parking guidance route is superimposed.

[0008] However, snow tracks are not only formed in parking spaces, but also in traffic lanes in parking lots. Especially when there is a lot of snow, many vehicles often trace the tracks that were initially formed and pass through them. As a result, a traffic lane where parking is prohibited may be mistaken for a parking location and displayed on the monitor, causing discomfort to the driver.

[0009] The present invention aims to provide a parking assistance device that can reduce the possibility of misidentifying a location where parking is prohibited as a parking space and reduce discomfort felt by the driver, even if the driver is unable to recognize a parking frame drawn on the road surface when attempting to park his or her vehicle in a parking space using a parking assistance function. [Means for solving the problem]

[0010] The present invention provides a parking assistance device that guides a vehicle to a parking space in a parking lot, the device comprising: an environmental information acquisition unit that acquires environmental information around the vehicle; a memory unit that stores information on a virtual parking frame required for parking the vehicle; a virtual parking frame setting unit that recognizes a 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 memory unit to the parking space; a rut detection unit that detects the presence or absence of a rut within the virtual parking frame set by the virtual parking frame setting unit based on the environmental information acquired by the environmental information acquisition unit; and a parking area setting unit that sets the virtual parking frame as a no-parking area when the rut detection unit detects a rut that intersects with at least two sides of the virtual parking frame. Effect of the Invention

[0011] 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 if wheel ruts intersect at least two sides of this virtual parking frame, the virtual parking frame is set as a no-parking area. Therefore, even if the parking frame drawn on the road surface cannot be recognized when attempting to park the vehicle in a parking space using the parking assistance function, the possibility of misidentifying a location where parking is prohibited as a parking space is reduced, and the discomfort felt by the driver can be reduced. [Brief description of the drawings]

[0012] [Figure 1] Schematic diagram of a parking assistance device [Diagram 2] Flowchart showing parking assistance control routine [Diagram 3] Flowchart showing parking assistance mode execution subroutine [Figure 4] Flowchart showing a subroutine for parking assistance in adverse environments [Figure 5A] FIG. 2 is an explanatory diagram of a virtual parking frame set for the host vehicle. [Figure 5B] FIG. 1 is an explanatory diagram showing a parking space larger than the virtual parking frame of the host vehicle. [Figure 5C] FIG. 1 is an explanatory diagram showing a parking space narrower than the virtual parking frame of the host vehicle. [Figure 6] A bird's-eye view showing the search status of no-parking areas [Figure 7] An overhead view showing a state in which a virtual parking frame is estimated as a parking space. [Figure 8] A bird's-eye view showing the state in which the vehicle is crossing the lane [Figure 9A] An explanatory diagram showing a parking space displayed from above on an HMI monitor [Figure 9B] An explanatory diagram showing a bird's-eye view of no-parking areas displayed on an HMI monitor DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] An embodiment of the present invention will be described below with reference to the drawings. A parking assistance device 1 shown in FIG. 1 is mounted on a vehicle M (see FIG. 6). The parking assistance device 1 includes a driving assistance control unit 11. The driving assistance control unit 11 is configured with a microcontroller including a CPU, a RAM, a ROM, a rewritable non-volatile memory (flash memory or EEPROM), and peripheral devices. The ROM stores programs and fixed data required for executing each process in the CPU. The RAM is provided as a work area for the CPU, and temporarily stores various data in the CPU. 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.

[0014] When the driver sets a desired assistance mode, the driving assistance control unit 11 performs driving assistance in the corresponding assistance mode. The driving assistance control unit 11 has a driving assistance mode and a parking assistance mode as the assistance modes.

[0015] In the driving assistance mode, map matching is performed on the road map in 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 the vehicle autonomously travels along a preset target route in a section where automatic driving is possible. In addition, in this driving assistance mode, on a road where automatic driving is difficult, well-known adaptive cruise control (ACC), active lane keep (ALK), and lane departure prevention (LDP) controls are executed, and when the vehicle M stays in the lane and detects a preceding vehicle, driving control is executed to follow the preceding vehicle.

[0016] On the other hand, in the parking assistance mode, when the driver selects the mode when the vehicle M enters a parking lot and drives the vehicle through the parking lot, the driving assistance control unit 11 searches for available parking spaces and no-parking areas where parking is presumably prohibited from the parking spaces in the parking lot, and notifies the driver. When the driver selects a desired parking space from among the available parking spaces, the vehicle M is automatically parked in the selected parking space. Alternatively, a parking guidance route for parking the vehicle in the parking space is superimposed on a surrounding image and an overhead view of the image of the vehicle M displayed on the HMI monitor 31 described later, thereby providing parking assistance when the driver parks the vehicle by himself / herself.

[0017] In addition, sensor units are connected to the input side of the driving assistance control unit 11 to acquire driving condition information (including position and direction) of the vehicle M and surrounding environment information of the vehicle M, which are required when executing the driving assistance mode and the parking assistance mode.

[0018] In this embodiment, the sensor units required for executing each assistance mode include a forward 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 vehicle M, left and right front side sensors 27, and left and right rear side sensors 28. The sensors 21, 26 to 28 constitute an environmental information acquisition unit of the present invention.

[0019] The forward recognition sensor 21 is an image sensor, and in this embodiment, it has a stereo camera consisting of a main camera 21a and a sub camera 21b, which use CCD or CMOS as an image sensor, and an image processing unit (IPU) 21c. Both cameras 21a and 21b have a predetermined base line length and are installed horizontally at equal intervals from the center of the vehicle width direction at a position close to the windshield, for example, above the rearview mirror at the front of the vehicle. The forward recognition sensor 21 processes images of environmental information of a predetermined area captured by both cameras 21a and 21b in the IPU 21c, and then transmits them to the driving assistance control unit 11.

[0020] The map locator unit 22 also 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 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 the road map database 22b includes road information (general roads, main roads, expressways, road shapes, road directions, number of lanes, lane width, etc.) required when executing the driving assistance mode, and static information of parking lots (position information of entrances and exits to the parking lots, space information within the lot, etc.) required when executing the parking assistance mode.

[0021] The driving assistance control unit 11 estimates the vehicle's position (current position) on the road map by map matching the position coordinates (latitude, longitude, altitude) of the vehicle M acquired by the GNSS sensor 22a onto the road map information stored in the road map database 22b.

[0022] The autonomous driving sensor 23 is a general term for sensors required when causing the host vehicle M to drive autonomously, 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 acceleration sensor that detects longitudinal acceleration, etc.

[0023] The rear sensor 26 is configured by combining a monocular camera using a CCD, CMOS, or the like as an imaging element with at least one of an ultrasonic sensor, a millimeter wave radar, a microwave radar, an infrared sensor, a laser radar, a LiDAR (Light Detection And Ranging), etc. Alternatively, the rear sensor 26 may be a stereo camera consisting of a main camera and a sub camera, similar to the above-mentioned forward recognition sensor 21.

[0024] The left and right front side sensors 27 are disposed, for example, on the left and right ridges of the front bumper of the vehicle M, respectively, and scan an area (scanning area) from the left and right diagonal front to the sides of the vehicle M in a fan-like shape. On the other hand, the left and right rear side sensors 28 are disposed, for example, on the left and right ridges of the rear bumper, and scan an area from the rear to the left and right of the vehicle M, which cannot be scanned by the left and right front side sensors 27, in a fan-like shape. Each of the side sensors 27, 28 is composed of a millimeter wave radar, a microwave radar, a LiDAR, or the like, and receives a reflected wave from a target (a parked vehicle Pv or an outer wall in the parking assistance mode) to obtain environmental information such as a distance and a direction from the vehicle M to the target (the parked vehicle Pv or the outer wall). In the following, for convenience, the parked vehicle Pv will be described as a representative target.

[0025] The driving assistance control unit 11 is also connected to an HMI (Human Machine Interface) monitor 31. This HMI monitor 31 displays a mode selection screen where the driver selects either a driving assistance mode or a parking assistance mode as an assistance mode executed by the driving assistance control unit 11, a parking space display screen that displays parking spaces where parking is possible as shown in Fig. 9A, and a no-parking area where parking is presumably prohibited as shown in Fig. 9B, and notifies the driver of the parking space, and the like. Incidentally, this HMI monitor 31 may also be used as a multi-information display of a combination meter or a navigation display device (navigation monitor) of a car navigation system.

[0026] In addition, a drive control actuator 32 and an alarm device 33 are connected to the output side of the driving assistance control unit 11. The 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 driving 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. In addition, the brake actuator adjusts the brake hydraulic pressure supplied to the brake wheel cylinders provided on each wheel. Furthermore, the alarm device 33 notifies the driver by voice of various information required when each assistance mode is being executed.

[0027] The driving assistance control unit 11 has a parking assistance control function that parks the vehicle M in a parking space on behalf of the driver, or assists the driver when parking the vehicle M in a parking space by driving the vehicle himself / herself. The parking assistance control executed by the driving assistance control unit 11 is specifically processed according to a parking assistance control routine shown in Fig. 2. This routine is executed at predetermined calculation intervals after the system is started.

[0028] In this routine, first, in step S1, vehicle position information estimated by map locator unit 22 is obtained, and the routine proceeds to step S2, where surrounding map information of the vehicle position is obtained from map locator unit 22 based on the vehicle position information.

[0029] Next, the process proceeds to step S3, where the vehicle position is matched with the surrounding map to check whether the vehicle M is entering a parking lot. If it is determined that the vehicle M is entering a parking lot, the process proceeds to step S4. If it is determined that the vehicle M is not entering a parking lot, the process exits the routine.

[0030] When the process proceeds to step S4, the notification device 33 issues a voice announcement to the driver asking whether or not to set the assistance mode to the parking assistance mode, and a parking assistance mode selection screen 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 or not the driver has selected the parking assistance mode, and if the driving assistance mode has been selected, the process proceeds to step S6. 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.

[0031] When the process proceeds to step S6, the parking assist mode is executed and the routine is exited. The parking assist mode is executed according to a parking assist mode execution subroutine shown in FIG. 3. In this subroutine, first, in step S11, the front and front side environmental 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 to divide a parking space is recognized from the acquired front and front side environmental information. This parking frame is recognized, for example, from the brightness difference between the road surface and the edge of the parking frame drawn on the road surface, or the change in intensity (reflectance) of the reflected light or reflected wave from the road surface and the parking frame, from the front and front side environmental information acquired by the forward recognition sensor 21 and the left and right front side sensors 27.

[0032] If the driving assistance control unit 11 determines that the parking frame is recognized, the process proceeds to step S13, where the favorable environment parking assistance process is executed, and the routine ends. Note that the favorable environment parking assistance process is the same as the conventional parking assistance process in which the vehicle M is guided to the parking space based on the parking frame, and therefore a description thereof will be omitted.

[0033] On the other hand, if it is determined that the parking space cannot be recognized, that is, the parking space drawn on the road surface cannot be recognized because the road surface of the parking lot is covered with snow or mud remaining after flooding, the process proceeds to step S14, executes parking support processing under adverse environment, and exits the routine. This parking support processing under adverse environment is executed according to the parking support subroutine under adverse environment shown in FIG.

[0034] 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 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 to a rectangular shape with four sides intersecting at right angles, the front-rear direction is set to the front-rear length of the host vehicle M, and the left and right have a necessary parking width Ws that is the vehicle width of the host vehicle M plus a margin width. Note that this necessary parking width Ws may be set as an initial setting by the driver.

[0035] Next, the process proceeds to step S22, where a parked vehicle PV, which is a representative target already parked in the parking lot, is recognized based on forward and front-side environmental information acquired from the forward recognition sensor 21, etc., of the parking lot where the vehicle M is traveling. Then, the process proceeds to step S23, where a virtual parking frame 41 is set at a position avoiding the parked vehicle Pv. The process in step S22 corresponds to the target detection unit of the present invention, and the process in step S23 corresponds to the virtual parking frame setting unit of the present invention.

[0036] 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 other hand, 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.

[0037] At that time, of course, when the 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 there are no parked vehicles Pv parked along the traffic lane at all, the virtual parking frame 41 is continuously set therebetween.

[0038] By the way, as shown in FIG. 6, when the parking frame drawn on the road surface is hidden by snow accumulation or mud, the traffic lane extending in the lateral direction in front of the host vehicle M cannot be recognized from the front and front-side environment information. Therefore, the driving support control unit 11 continuously sets the virtual parking frame 41 in the space set as this traffic lane.

[0039] Thereafter, the process proceeds to step S24 to check whether or not the rut 101 is detected in the set virtual parking frame 41. Note that the processing in this step corresponds to the rut detection unit of the present invention.

[0040] This rut 101, for example, based on the front and front-side environment information acquired by the front recognition sensor 21 and the left and right front-side sensors 27, focuses on each virtual parking frame 41, and from the luminance difference generated at the step (edge) with the snow accumulation surface or mud surface derived from the rut 101, or the change in the intensity of the reflected light or reflected wave (reflectivity), the rut 101 is recognized by performing well-known pattern matching processing or the like on a series of feature points indicated by the edge of the rut.

[0041] Then, if the wheel track 101 is detected in the virtual parking frame 41, proceed to step S25. If the wheel track 101 is not detected in the virtual parking frame 41, it is estimated that no vehicle has been parked yet and that the space is highly likely to be available for parking, and jump to step S27.

[0042] When the process proceeds to step S25, it is checked whether the wheel rut 101 intersects with two or more sides of the virtual parking frame 41. As shown in Fig. 7, when the wheel rut 101 intersects with only one side of the virtual parking frame 41, it is estimated that the wheel rut 101 is made by a vehicle entering or exiting the parking space, and it is estimated that the wheel rut 101 is highly likely to be a parking space. On the other hand, as shown in Fig. 8, when the wheel rut 101 intersects with two sides of the virtual parking frame 41, it is estimated that the wheel rut 101 is highly likely to be a parking space, in other words, it is estimated that the wheel rut 101 is highly likely to be a no-parking area.

[0043] Therefore, for example, as shown in Fig. 6, when virtual parking frames 41 are set continuously along a lane in a place where the lane is supposed to be, at least two sides of each virtual parking frame 41 are intersected by wheel tracks 101. Even if a virtual parking frame 41 is set at a place where a lane extending in the longitudinal direction where the vehicle M is traveling intersects with a lane extending in the lateral direction, the virtual parking frame 41 is clearly presumed to be a no-parking area because the wheel tracks 101 intersect with the four sides of the virtual parking frame 41.

[0044] Then, when it is determined that the rut 101 intersects two or more sides of the virtual parking frame 41, proceed to step S26. On the other hand, when it is determined that the rut 101 intersects only one side of the virtual parking frame 41, branch to step S27.

[0045] When the process proceeds to step S26, the parking priority of the currently recognized virtual parking frame 41 is set to low, and the process proceeds to step S28. When the process branches from step S24 or step S25 to step S27, the parking priority of the currently recognized virtual parking frame 41 is set to high, and the process proceeds to step S28. In this embodiment, the virtual parking frame 41 with the parking priority set to low is set as a no-parking area where parking is prohibited, such as a lane, and is temporarily stored in the storage unit. In addition, the virtual parking frame 41 with the parking priority set to high is set as a parking available space Ps, and is temporarily stored in the storage unit. The processes in steps S25 to S27 correspond to the parking area setting unit of the present invention.

[0046] Then, when the process proceeds from step S26 or step S27 to step S28, the virtual parking frame 41 associated with the parking priority level is displayed by driving the HMI monitor 31, which is the display unit, and the process proceeds to step S29. The process in step S28 corresponds to the display drive unit of the present invention.

[0047] 9A and 9B show examples of display on the HMI monitor 31. When the vehicle M approaches a virtual parking frame 41 set by the driving assistance control unit 11, the virtual parking frame 41 according to the parking priority is displayed on the HMI monitor 31 together with an image showing the position of the vehicle M. FIG. 9A shows an aspect in which a virtual parking frame 41 with a high parking priority is displayed as a parking available space Ps. In this case, the parking available space Ps is highlighted in blue or the like to indicate that parking is available.

[0048] On the other hand, Fig. 9B shows a display of a virtual parking frame 41 with a low parking priority. For example, in Fig. 6, the virtual parking frames 41 with a low parking priority are set consecutively on a traffic lane, and the consecutive virtual parking frames 41 are displayed on the HMI monitor 31 as a no-parking area Anp that is integrated in the horizontal direction. In this case, the consecutive virtual parking frames 41 are highlighted in a color such as orange to call attention. By visually checking the available parking space Ps or the no-parking area Anp displayed on the HMI monitor 31, the driver can instantly recognize whether the location is available for parking or not.

[0049] Thereafter, the process proceeds to step S29, where it is checked whether the parking assistance mode has ended, and if it is determined that the mode has ended, the process exits the routine. On the other hand, if it is determined that the parking assistance mode is continuing, the process returns to step S22, where the next parking space is recognized.

[0050] In this way, in this embodiment, the virtual parking frame is superimposed on the image of the environmental information acquired in the parking lot, and when the wheel tracks 101 that intersect at least two sides of the virtual parking frame are detected, it is estimated that the space is highly likely to be prohibited from parking, and the parking priority is set low. Therefore, even if the driver is trying to park his / her vehicle in the parking space using the parking assistance function and is unable to recognize the parking frame drawn on the road surface, the possibility of misidentifying a place where parking is prohibited as a parking space is suppressed. As a result, the discomfort given to the driver can be reduced. In addition, the no-parking area Anp is displayed on the HMI monitor 31, so the driver can easily grasp it visually.

[0051] The present invention is not limited to the above-described embodiment, and for example, when the parking space Ps is displayed on the HMI monitor 31 in step S28 of Fig. 4, the driver may select the parking space Ps, and the driving assistance control unit 11 may set the parking space Ps as a target parking space and automatically park the vehicle M in the target parking space. Alternatively, a parking guide route for guiding the vehicle M to the target parking space may be superimposed on the HMI monitor 31 to assist the driver in manually parking the vehicle. [Explanation of symbols]

[0052] 1...Parking assistance device, 11...Driver assistance control unit, 21...Forward 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...Right and left rear side sensors, 31…HMI monitor, 32...Drive control actuator, 33...Alarm device, 41…Virtual parking space, 101...Wheel rut, Anp…No parking area, M…own vehicle, Ps… Parking space available, Pv...parked vehicles, Wp…interval, Ws… Required parking width

Claims

1. A parking assistance device that guides a vehicle to a parking space in a parking lot, an environmental information acquisition unit that acquires environmental information about the surroundings of the host vehicle; A storage unit that stores information on a virtual parking frame required for parking the vehicle; A virtual parking frame setting unit that recognizes the parking space of 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 to the parking space; A rut detection unit that detects the presence or absence of a rut within the virtual parking frame set by the virtual parking frame setting unit based on the environmental information acquired by the environmental information acquisition unit; a parking area setting unit that sets the virtual parking frame to a no-parking area when the wheel wheel detection unit detects the wheel wheel that intersects with at least two sides of the virtual parking frame; A parking assistance device comprising:

2. a target detection unit that detects a target in the parking lot based on the environmental information acquired by the environmental information acquisition unit, The virtual parking frame setting unit sets the virtual parking frame at a position that avoids the target detected by the target detection unit.

2. The parking assistance device according to claim 1.

3. a display driving unit that displays the no-parking area on a display unit when the virtual parking frame is set as the no-parking area by the parking area setting unit; 3. The parking assistance device according to claim 1, further comprising:

4. The parking area setting unit detects the wheel track that intersects only one side of the virtual parking frame by the wheel track detection unit, or when the wheel track is not detected in the virtual parking frame, sets the virtual parking frame as a parking space.

3. The parking assistance device according to claim 1 or 2.

5. a display driving unit that displays the available parking space on a display unit when the virtual parking frame is set as the available parking space by the parking area setting unit; 5. The parking assistance system of claim 4, further comprising:

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