阅读说明：本技术 驻车位辨识系统及包括该驻车位辨识系统的驻车辅助系统 (Parking position identification system and parking auxiliary system comprising same ) 是由 原悠记 照田八州志 于 2021-03-30 设计创作，主要内容包括：本发明提供驻车位辨识系统及包括该驻车位辨识系统的驻车辅助系统。所述驻车位辨识系统包括外部环境信息获取装置以及候选驻车位检测装置。所述候选驻车位检测装置包括：虚拟线计算单元,其构造成计算连接彼此相邻的驻车位线的车行道侧端部的虚拟线；角度计算单元,其构造成计算所述虚拟线与所述驻车位线中的一条驻车位线之间的角度；驻车类型确定单元,其构造成确定驻车类型；以及候选驻车位设定单元,其构造成基于所述驻车位线的位置在所述驻车位线之间的区域中设定至少一个临时驻车位,并将所述临时驻车位中的可用驻车区域设定为所述候选驻车位。(The invention provides a parking space identification system and a parking auxiliary system comprising the same. The parking space identification system comprises an external environment information acquisition device and a candidate parking space detection device. The parking position candidate detection device includes: a virtual line calculation unit configured to calculate a virtual line connecting the roadway-side ends of the parking spots adjacent to each other; an angle calculation unit configured to calculate an angle between the dummy line and one of the parking bit lines; a parking type determination unit configured to determine a parking type; and a candidate parking space setting unit configured to set at least one temporary parking space in a region between the parking space lines based on a position of the parking space line, and set an available parking region in the temporary parking spaces as the candidate parking space.)

1. The utility model provides a parking stall identification system, parking stall identification system installs on the vehicle for discern at least one parking stall position that sets up between the many parallel parking stall lines of road one side, parking stall identification system includes:

an external environment information acquisition device configured to acquire a position of the parking space line; and

a parking position candidate detection device configured to detect a parking type including an oblique parking and a vertical parking and at least one parking position candidate, which is a parking available region candidate, based on a position of the parking line,

wherein, candidate parking stall detection device includes:

a virtual line calculation unit configured to calculate a virtual line connecting road-side ends of the parking bit lines adjacent to each other;

an angle calculation unit configured to calculate an angle between the virtual line calculated by the virtual line calculation unit and one of the parking lines;

a parking type determination unit configured to determine the parking type based on an angle between the dummy line and the one of the parking bit lines; and

a parking position candidate setting unit configured to set at least one temporary parking space in a region between the parking position lines based on a position of the parking position line, and set an available parking region among the temporary parking spaces as the parking position candidate.

2. The park recognition system according to claim 1, wherein the park type determination unit determines the park type as either oblique parking or vertical parking when three or more park lines are recognized.

3. The parking space recognition system according to claim 2, wherein the parking type determination unit determines the parking type as oblique parking when the angle calculated by the angle calculation unit is within a prescribed first angle range that is greater than 0 degrees and less than 180 degrees, and

the parking type determination unit determines the parking type as vertical parking when the angle calculated by the angle calculation unit is within a second angle range including 90 degrees and excluding the first angle range.

4. The park recognition system of claim 3, wherein the first angular range includes: a prescribed angular range comprising 45 degrees or 135 degrees; and another prescribed angular range including 60 degrees or 120 degrees.

5. The parking space recognition system according to any one of claims 1 to 4, wherein, when the parking type determination unit determines the parking type as an oblique parking, the parking space candidate setting unit does not set the parking space candidate between a first parking space line that is a parking space line closest to the vehicle and a second parking space line that is a parking space line adjacent to the first parking space line.

6. The park position recognition system according to any one of claims 1 to 4, wherein, when the park type determination unit determines the park type as a vertical park, the park position candidate setting unit sets the temporary park position to include a region between a first park position line that is a park position line closest to the vehicle and a second park position line that is a park position line adjacent to the first park position line.

7. The park position recognition system according to any one of claims 1 to 4, wherein the parking position candidate setting unit sets the temporary park position between the park position lines in a case where at least two of the park position lines are recognized.

8. A parking assist system for parking a vehicle in a parking space, the parking assist system comprising:

the park position recognition system of any one of claims 1-7;

a display device configured to display the at least one candidate parking spot;

a selection input member configured to receive a selection operation of a target parking place by a user from the at least one candidate parking place displayed on the display device; and

a control device configured to execute a drive process to autonomously move the vehicle to the target parking space based on a determination result of the candidate parking space detection device.

Technical Field

The present invention relates to a parking space identification system for identifying a parking space and a parking assist system for autonomously moving a vehicle to the identified parking space and parking the vehicle therein.

Background

A known parking assist system includes a parking space recognition device mounted on a host vehicle (hereinafter simply referred to as "vehicle") that detects a parking space located ahead of the vehicle in a moving direction of the vehicle and notifies a driver of the parking space (e.g., JP2016-016681 a). The above parking space identifying device detects an available parking space (i.e., a parking space in which a vehicle can be parked) from a captured image of the front of the vehicle in its moving direction based on the feature of the parking line and the parking type. The characteristics of the parking lines include the presence or absence of the parking lines, the interval between the parking lines, the shape of the parking lines, the color of the parking lines, and the angle between the moving direction of the vehicle and the parking lines. The parking type represents a parking form of the vehicle with respect to a parking line (e.g., vertical parking, oblique parking, parallel parking), and is determined by the parking position recognition means by using an angle between a moving direction of the vehicle and the parking line and an interval between parking lines adjacent to each other.

An angle between the moving direction of the vehicle and the parking line varies depending on the moving direction of the vehicle. Therefore, for example, in a case where the vehicle approaches the oblique parking spot line (i.e., the parking spot line for oblique parking) from a direction perpendicular to the oblique parking spot line, the angle between the moving direction of the vehicle and the oblique parking spot line may become substantially 90 degrees, and thus, the oblique parking may be erroneously recognized as the vertical parking.

Disclosure of Invention

In view of such problems of the prior art, a primary object of the present invention is to prevent erroneous recognition of a parking type in a parking space recognition system configured to determine a parking type and set a parking space and in a parking assist system for parking a vehicle in a parking space recognized by the parking space recognition system.

To achieve such an object, one embodiment of the present invention provides a parking space identifying system S mounted on a vehicle for identifying at least one parking space between a plurality of parallel parking space lines 55 provided on one side of a road 57, the parking space identifying system comprising: an external environment information acquisition device 7 configured to acquire a position of the parking space line; and a candidate parking space detection device 15 configured to detect a parking type including oblique parking and vertical parking and at least one candidate parking space based on a position of the parking line, the candidate parking space being a candidate available parking area, wherein the candidate parking space detection device includes: a virtual line calculation unit 61 configured to calculate a virtual line 57 connecting road-side ends of the parking lines adjacent to each other; an angle calculation unit 62 configured to calculate an angle θ between the virtual line calculated by the virtual line calculation unit and one of the parking lines; a parking type determination unit 63 configured to determine the parking type based on an angle between the dummy line and the one of the parking bit lines; and a candidate parking space setting unit 64 configured to set at least one temporary parking space 52X in a region between the parking space lines based on the position of the parking space line, and set an available parking region in the temporary parking spaces as the candidate parking space.

According to this configuration, the parking type is determined not based on the moving direction of the vehicle but based on the shape of the parking line, and therefore erroneous recognition of the parking type can be prevented.

In the above configuration, when three or more of the parking lines are recognized, the parking type determination unit determines the parking type as either oblique parking or vertical parking.

According to this configuration, when three or more parking lines are identified, the parking type is determined as either oblique parking or vertical parking. Therefore, it is possible to prevent erroneous recognition of the parking type, as compared with the case where the parking type is determined as the oblique parking or the vertical parking when the two parking lines are recognized.

In the above configuration, the parking type determination unit determines the parking type as oblique parking when the angle calculated by the angle calculation unit is within a prescribed first angle range that is greater than 0 degrees and less than 180 degrees, and determines the parking type as vertical parking when the angle calculated by the angle calculation unit is within a second angle range that includes 90 degrees and excludes the first angle range.

According to this configuration, the parking type can be easily determined by determining the angle between the dummy line and one of the parking bit lines.

In the above configuration, the first angle range includes: a prescribed angular range comprising 45 degrees or 135 degrees; and another prescribed angular range including 60 degrees or 120 degrees.

According to this configuration, it is possible to appropriately park the vehicle in the oblique parking space in which the angle between the virtual line and one of the parking lines is substantially 45 degrees (or substantially 135 degrees) and the oblique parking space in which the angle between the virtual line and one of the parking lines is substantially 60 degrees (or substantially 120 degrees).

In the above configuration, when the parking type is determined as an oblique parking by the parking type determination unit, the parking space candidate setting unit does not set the parking space candidate between a first parking space line that is a parking space line closest to the vehicle and a second parking space line that is a parking space line adjacent to the first parking space line.

In a parking lot for oblique parking, it is often difficult to recognize the closest parking space line (i.e., the parking space line closest to the vehicle) immediately after the vehicle enters the parking lot. Therefore, the area between the closest parking spot line and its neighboring parking spot line may not be suitable as a parking position. According to the above configuration, the region other than the region between the closest parking space line (first parking space line) and its adjacent parking space line (second parking space line) is set as the parking space candidate. Therefore, it is possible to prevent the region unsuitable for the parking position of the seat from being set as the parking candidate space.

In the above configuration, when the parking type is determined as the vertical parking by the parking type determination unit, the parking position candidate setting unit sets the temporary parking position to include a region between a first parking position line that is a parking position line closest to the vehicle and a second parking position line that is a parking position line adjacent to the first parking position line.

According to this configuration, a larger number of temporary parking spaces can be appropriately set. Therefore, a greater variety of candidate parking spaces can be provided to the user, so that the user can move the vehicle to a desired position and park the vehicle therein.

In the above configuration, the parking position candidate setting unit sets the temporary parking position between the parking position lines in a case where at least two of the parking position lines are recognized.

According to this configuration, even if only two parking spaces are recognized, a temporary parking space is provided between the two parking spaces. Therefore, the candidate parking space is more easily provided, thereby improving the convenience of the vehicle.

Another embodiment of the present invention provides a parking assist system 1 for parking a vehicle in a parking space, the parking assist system including: the parking position identification system described above; a display device 32 configured to display the at least one candidate parking spot; a selection input member 35 configured to receive a selection operation of a target parking place by a user from the at least one candidate parking places displayed on the display device; and a control device 15 configured to execute a drive process to autonomously move the vehicle to the target parking space based on a determination result of the candidate parking space detection device.

According to this configuration, the vehicle can autonomously park in the target parking space.

Therefore, according to the above configuration, in the parking space recognition system configured to determine the parking type and set the parking space, and in the parking assist system that parks the vehicle in the parking space recognized by the parking space recognition system, it is possible to prevent erroneous recognition of the parking type.

Drawings

Fig. 1 is a functional block diagram of a vehicle provided with a parking assist system according to an embodiment of the invention;

fig. 2 is a flowchart of the automatic parking process;

fig. 3A is a diagram showing a screen display (parking search screen) of the touch panel during the target parking space reception process;

fig. 3B is a diagram showing a screen display (parking screen) of the touch panel during the driving process;

fig. 3C is a view showing a screen display (parking screen) of the touch panel at the time of completion of automatic parking of the vehicle;

fig. 4 is an explanatory diagram showing parking lines and temporary parking spots in a parking lot providing an oblique parking spot;

fig. 5A is an explanatory diagram showing parking bit lines and temporary parking spaces in a parking lot providing vertical parking spaces;

fig. 5B is an enlarged view of a portion surrounded by a two-dot chain line circle in fig. 5A; and

fig. 6 is a flowchart showing the extraction process.

Detailed Description

Hereinafter, one embodiment of the present invention will be described in detail with reference to the accompanying drawings.

The parking assist system 1 configured to assist parking of the vehicle includes a parking space recognition system S therein, and the parking assist system 1 is mounted on a vehicle such as an automobile provided with a vehicle control system 2, the vehicle control system 2 being configured to autonomously move the vehicle.

As shown in fig. 1, the vehicle control system 2 includes a powertrain 4, a brake device 5, a steering device 6, an external environment sensor 7, a vehicle sensor 8, a navigation device 10, an operation input member 11, a driving operation sensor 12, a state detection sensor 13, a human-machine interface (HMI)14, and a control device 15. The above components of the vehicle control system 2 are connected to each other so that signals CAN be transmitted therebetween via a communication mechanism such as a Controller Area Network (CAN).

The powertrain 4 is a device configured to apply driving force to the vehicle. For example, the powertrain 4 includes a power source and a transmission. The power source includes at least one of an internal combustion engine such as a gasoline engine and a diesel engine and an electric motor. In the present embodiment, the powertrain 4 includes an automatic transmission 16 and a shift actuator 17 for changing a gear position of the automatic transmission 16 (a gear position of the vehicle). The brake device 5 is a device configured to apply a braking force to the vehicle. For example, the braking device 5 includes: a brake caliper configured to press a brake pad toward a brake rotor; and an electric cylinder configured to drive the caliper by oil pressure. The brake device 5 may include an electric parking brake device configured to restrict rotation of the wheel via a cable. The steering device 6 is a device for changing the steering angle of the wheels. For example, the steering device 6 includes: a rack-and-pinion mechanism configured to steer (rotate) wheels; and an electric motor configured to drive the rack-and-pinion mechanism. The drive train 4, the brake device 5 and the steering device 6 are controlled by a control device 15.

The external environment sensor 7 functions as an external environment information acquisition unit for detecting electromagnetic waves, acoustic waves, and the like from the surroundings of the vehicle to detect an object outside the vehicle and acquire the surrounding information of the vehicle. The external environment sensor 7 includes a sonar 18 and an external camera 19. The external environment sensor 7 may also comprise a millimeter wave radar and/or a lidar. The external environment sensor 7 outputs the detection result to the control device 15.

Each sonar 18 is composed of a so-called ultrasonic sensor. Each sonar 18 emits an ultrasonic wave to the surroundings of the vehicle and captures an ultrasonic wave reflected by an object around the vehicle, thereby detecting the position (distance and direction) of the object. A plurality of sonars 18 are provided at each of the rear and front of the vehicle. In the present embodiment, two pairs of sonars 18 are provided on the rear bumper so as to be laterally spaced from each other, two pairs of sonars 18 are provided on the front bumper so as to be laterally spaced from each other, one pair of sonars 18 are provided on the front end portion of the vehicle such that two sonars 18 forming a pair are provided on the left and right side surfaces of the front end portion of the vehicle, and one pair of sonars 18 are provided on the rear end portion of the vehicle such that two sonars 18 forming a pair are provided on the left and right side surfaces of the rear end portion of the vehicle. That is, the vehicle is provided with six pairs of sonars 18 in total. The sonar 18 provided on the rear bumper mainly detects the position of an object behind the vehicle. The sonar 18 provided on the front bumper mainly detects the position of an object in front of the vehicle. The sonars 18 provided on the left and right side faces of the front end portion of the vehicle detect the positions of objects on the left and right outer sides of the front end portion of the vehicle, respectively. The sonars 18 provided on the left and right side faces of the rear end portion of the vehicle detect the positions of objects on the left and right outer sides of the rear end portion of the vehicle, respectively.

The external camera 19 is a device configured to capture an image of the surroundings of the vehicle. For example, each external camera 19 is composed of a digital camera using a solid-state imaging element such as a CCD or a CMOS. The external cameras 19 include a front camera for capturing an image in front of the vehicle and a rear camera for capturing an image behind the vehicle. The exterior cameras 19 may include a pair of left and right cameras disposed near a rear view mirror of the vehicle to capture images of both left and right sides of the vehicle.

The vehicle sensor 8 includes: a vehicle speed sensor configured to detect a speed of the vehicle; an acceleration sensor configured to detect an acceleration of the vehicle; a yaw rate sensor configured to detect an angular velocity about a vertical axis of the vehicle; and a direction sensor configured to detect a direction of the vehicle. For example, the yaw rate sensor is composed of a gyro sensor.

The navigation device 10 is a device configured to obtain a current position of a vehicle and provide route guidance to a destination or the like. The navigation device 10 includes a GPS receiving unit 20 and a map storage unit 21. The GPS receiving unit 20 identifies the position (latitude and longitude) of the vehicle based on a signal received from an artificial satellite (positioning satellite). The map storage unit 21 is constituted by a known storage device such as a flash memory or a hard disk, and stores map information.

The operation input member 11 is provided in the vehicle compartment to receive an input operation by an occupant (an embodiment of a user) to control the vehicle. The operation input member 11 includes a steering wheel 22, an accelerator pedal 23, a brake pedal 24 (brake input member), and a shift lever 25 (shift member). The shift lever 25 is configured to receive an operation for selecting a gear of the vehicle.

The driving operation sensor 12 detects an operation amount of the operation input member 11. The driving operation sensor 12 includes: a steering angle sensor 26 configured to detect a steering angle of the steering wheel 22; a brake sensor 27 configured to detect a stepping amount of the brake pedal 24, and an acceleration sensor 28 configured to detect a stepping amount of the accelerator pedal 23. The driving operation sensor 12 outputs the detected operation amount to the control device 15.

The state detection sensor 13 is a sensor configured to detect a state change of the vehicle according to an operation of an occupant. The operations of the occupant detected by the state detection sensor 13 include an operation indicating an intention of the occupant to get off the vehicle (intention to come from getting on or off the vehicle) and an operation indicating no intention of the occupant to check the environment around the vehicle during an autonomous parking operation or an autonomous driving-off operation. The state detection sensor 13 includes a door opening/closing sensor 29 configured to detect opening and/or closing of a vehicle door, and a seat belt sensor 30 configured to detect a fastening state of a seat belt as sensors for detecting an operation indicating an intention to get off the vehicle. The state detection sensor 13 includes a mirror position sensor 31 configured to detect the position of the mirror as a sensor for detecting an operation corresponding to the out-of-position intention. The state detection sensor 13 outputs a signal indicating the detected change in the vehicle state to the control device 15.

The HMI 14 is an input/output device for receiving an input operation of an occupant and notifying the occupant of various information via display and/or voice. The HMI 14 includes, for example: a touch panel 32, the touch panel 32 including a display screen such as a liquid crystal display or an organic EL display, and being configured to receive an input operation by an occupant; a sound generating device 33 such as a buzzer or a speaker; a parking main switch 34; and a selection input member 35. The parking owner switch 34 receives an input operation of the occupant to perform a selected one of an automatic parking process (automatic parking operation) and an automatic drive-off process (automatic drive-off operation). The parking owner switch 34 is a so-called momentary switch that is turned on only when the occupant performs a pressing operation (push operation). The selection input member 35 receives selection operation of the occupant regarding selection of the automatic parking process and the automatic drive-off process. The selection input member 35 may be composed of a rotary selector switch, which preferably requires pressing as a selection operation.

The control device 15 is composed of an Electronic Control Unit (ECU) including a CPU, a nonvolatile memory such as a ROM, a volatile memory such as a RAM, and the like. The CPU executes operation processing according to the program, so that the control device 15 executes various types of vehicle control. The control device 15 may be composed of one piece of hardware, or may be composed of a unit including a plurality of pieces of hardware. Further, the functions of the control device 15 may be performed at least partially by hardware such as LSI, ASIC, and FPGA, or may be performed by a combination of software and hardware.

Further, the control device 15 performs arithmetic processing in accordance with the program, thereby performing conversion processing of the image (video) captured by the external camera 19 to generate a top view image corresponding to a plan view of the vehicle and its surrounding area and a bird's eye view image corresponding to a three-dimensional image of the portion of the vehicle and its surrounding area located in the moving direction when viewed from above. The control device 15 may generate the overhead image by combining the images of the front camera, the rear camera, and the left and right cameras, and may generate the bird's-eye view image by combining the image captured by the front camera or the rear camera facing the moving direction and the image captured by the left and right cameras.

The parking assist system 1 is a system for performing a so-called automatic parking process and a so-called automatic drive-off process in which a vehicle autonomously moves to a prescribed target space (a target drive-off space or a target parking space 53 shown in fig. 3B) selected by an occupant to park or drive off the vehicle.

The parking assist system 1 includes: a control device 15; an external environment sensor 7 (sonar 18 and external camera 19) as an external environment information acquisition means; a touch panel 32 as a display device configured to receive a selection operation; and a selection input member 35. The parking space recognition system S includes a control device 15 and an external environment sensor 7 (sonar 18 and external camera 19) as an external environment information acquisition device.

The control device 15 controls the powertrain 4, the brake device 5, and the steering device 6 to perform an autonomous parking operation, thereby autonomously moving the vehicle to the target parking space 53 and parking the vehicle in the target parking space 53; and performing an autonomous drive-off operation, thereby autonomously moving the vehicle to the target drive-off space and driving the vehicle off at the target drive-off space. To perform such an operation, the control device 15 includes an external environment recognizing unit 41, a vehicle position identifying unit 42, an action planning unit 43, a travel control unit 44, a vehicle abnormality detecting unit 45, and a vehicle state determining unit 46.

The external environment recognition unit 41 recognizes an obstacle (e.g., a parked vehicle or a wall) existing around the vehicle based on the detection result of the external environment sensor 7, thereby obtaining information about the obstacle. Further, the external environment recognition unit 41 analyzes the image captured by the external camera 19 based on a known image analysis method such as pattern matching, thereby determining whether a wheel stopper or an obstacle is present, and obtains the size of the wheel stopper or the obstacle in the case where the wheel stopper or the obstacle is present. Further, the external environment recognition unit 41 may calculate a distance to the obstacle based on the signal from the sonar 18 to obtain the position of the obstacle.

In addition, the external environment recognition unit 41 can acquire, for example, a lane and a parking line 55 on a road (see fig. 4 and 5A) by analyzing the detection result of the external environment sensor 7 (more specifically, an image captured by the external camera 19) based on a known image analysis method such as pattern matching. Lanes on the road are defined by road markings. The parking space line 55 is constituted by a white line or the like provided on the surface of the parking lot. The parking space line 55 is a boundary line for defining boundaries of both lateral sides of at least one parking space 52.

The parking lines 55 are arranged in parallel with each other and are provided on one side (or one side edge) of a roadway 56 (road) on which vehicles entering the parking lot move. Each parking line 55 forms a prescribed parking angle δ with respect to the extending direction of the roadway 56 (road). Parking spaces 52 for parking the vehicle are defined between the parking spaces 55 adjacent to each other. The vehicle moves to the parking position 52 in a predetermined direction forming a parking angle δ with respect to the extending direction of the roadway 56.

An angle θ (see fig. 4 and 5A) between the dummy line 57 and one of the parking bit lines 55 (more specifically, an extension line of a center line of one of the parking bit lines 55 in an extending direction thereof; hereinafter, simply referred to as "parking bit line 55") is equal to the parking angle δ. The dummy line 57 is a line connecting a roadway-side end portion of one parking space line 55 (i.e., an end portion on one side of the roadway 56) and a roadway-side end portion of another parking space line 55 adjacent to the one parking space line 55. The parking angle δ is determined based on the parking type including the oblique parking and the vertical parking. Next, an angle θ between two straight lines (the dummy line 57 and the parking line 55) indicates a smaller angle between the two straight lines. That is, the angle θ between the two straight lines is defined as an angle equal to or greater than 0 degrees and equal to or less than 90 degrees.

In the case where the parking type is the bevel parking, the parking angle δ is set to a prescribed value equal to or greater than 0 degrees and less than 90 degrees. In the case where the parking type is the bevel parking, the parking angle δ may be set to 45 degrees or 60 degrees. On the other hand, in the case where the parking type is the vertical parking, the parking angle δ is set to 90 degrees.

The vehicle position identification unit 42 identifies the position of the vehicle (own vehicle) based on the signal from the GPS receiving unit 20 of the navigation device 10. Further, the vehicle position recognition unit 42 may obtain the vehicle speed and yaw rate from the vehicle sensor 8 in addition to the signal from the GPS receiving unit 20, and recognize the position and attitude of the vehicle by means of so-called inertial navigation.

The travel control unit 44 controls the powertrain 4, the brake device 5, and the steering device 6 to cause the vehicle to travel based on the travel control command from the action planning unit 43.

The vehicle abnormality detection unit 45 detects an abnormality of the vehicle (hereinafter referred to as "vehicle abnormality") based on signals from various devices and sensors. The vehicle abnormality detected by the vehicle abnormality detection unit 45 includes a malfunction of various devices (e.g., the powertrain 4, the brake device 5, and the steering device 6) required to drive the vehicle and a malfunction of various sensors (e.g., the external environment sensor 7, the vehicle sensor 8, and the GPS receiving unit 20) required to autonomously move the vehicle. Further, the vehicle abnormality includes a malfunction of the HMI 14.

The vehicle state determination unit 46 acquires the state of the vehicle based on signals from various sensors provided in the vehicle, and determines whether the vehicle is in a prohibition state in which autonomous movement of the vehicle (i.e., an autonomous parking operation or an autonomous drive-away operation) should be prohibited. When the occupant performs a driving operation (reset operation) of the operation input member 11, the vehicle state determination unit 46 determines that the vehicle is in the prohibition state. The reset operation is an operation of resetting (canceling) autonomous movement of the vehicle (i.e., an autonomous parking operation or an autonomous drive-off operation).

More specifically, the vehicle state determination unit 46 may determine to start the reset operation when the depression amount of the brake pedal 24 acquired (detected) by the brake sensor 27 reaches or exceeds a prescribed threshold value (hereinafter referred to as a "depression threshold value"). Additionally or alternatively, the vehicle state determination unit 46 may determine to start the reset operation when the depression amount of the accelerator pedal 23 acquired (detected) by the accelerator sensor 28 reaches or exceeds a prescribed threshold value. The vehicle state determination unit 46 may also determine to start the reset operation when the rate of change of the steering angle obtained (detected) by the steering angle sensor 26 reaches or exceeds a prescribed threshold value.

Further, when the vehicle is in a state reflecting the intention of the occupant to get off (intention to get on or off from the vehicle), the vehicle state determination unit 46 determines that the vehicle is in the prohibition state based on the detection result of the state detection sensor 13. More specifically, when the door open/close sensor 29 detects that the vehicle door is opened, the vehicle state determination unit 46 determines that the vehicle is in the prohibition state. Further, when the seatbelt sensor 30 detects that the seatbelt is released, the vehicle state determination unit 46 determines that the vehicle is in the prohibition state.

When the vehicle is in a prescribed state and the HMI 14 or the parking master switch 34 receives a prescribed input of a user corresponding to a request for the automatic parking process or the automatic drive-off process, the action planning unit 43 executes the automatic parking process (autonomous parking operation) or the automatic drive-off process (autonomous drive-off operation). More specifically, when the vehicle is stopped or the vehicle is moving at a low speed equal to or less than a prescribed vehicle speed (vehicle speed at which a candidate parking space can be searched for), the action planning unit 43 executes the automatic parking process in the case where a prescribed input corresponding to the automatic parking process is made. When the vehicle is stopped, the action planning unit 43 executes the automatic drive-off process (parallel drive-off process) when a prescribed input corresponding to the automatic drive-off process is performed. The process to be executed (automatic parking process or automatic drive-off process) may be selected by the action planning unit 43 based on the state of the vehicle. Alternatively, the above selection may also be made by the occupant via the touch panel 32 or the selection input member 35. When executing the automatic parking process, the action planning means 43 first displays a parking search screen for setting the target parking space 53 on the touch panel 32. After the target parking space 53 is set, the action planning unit 43 displays the parking screen on the touch panel 32. When the automatic drive-away process is executed, the action planning unit 43 first causes the touch panel 32 to display a drive-away search screen for setting a target drive-away position. After the target departure position is set, the action planning means 43 displays the departure screen on the touch panel 32.

Next, the automatic parking process will be described with reference to fig. 2. First, the action planning unit 43 performs an acquisition process (step ST1) to acquire at least one candidate parking space 60 that is a candidate for an available parking area (i.e., an area in which the vehicle can be parked) and a target parking position in which the vehicle is parked. More specifically, when the vehicle is stopped, the action planning unit 43 first causes the touch panel 32 of the HMI 14 to display a notification indicating that the occupant moves the vehicle straight. When an occupant (hereinafter, referred to as a "driver") sitting in a driver seat moves the vehicle straight, the external environment recognition unit 41 acquires the position and size of an obstacle and the position of the parking line 55 based on a signal from the external environment sensor 7. The action planning unit 43 performs processing (hereinafter referred to as "extraction processing") of extracting a candidate parking space 60, which is an available parking space 52 defined by the parking space line 55 (i.e., a parking space 52 where the vehicle can be parked), based on the position and size of the obstacle and the position of the parking space line 55 acquired by the external environment recognition unit 41.

In the case where the vehicle has moved a prescribed distance and at least one candidate parking space 60 has been extracted, the action planning unit 43 notifies the driver that the candidate parking space 60 has been extracted. The notification may be issued to the driver by a display on the touch panel 32 or by a voice generated by a speaker.

Thereafter, the action planning unit 43 causes the touch panel 32 to display at least one already acquired parking space candidate 60, and executes a target parking space reception process (step ST2) to receive the selection operation of the occupant. The selection operation is an operation of selecting a target parking space 53 in which the occupant wants to park the vehicle from among the at least one candidate parking spaces 60 displayed on the touch panel 32. More specifically, the action planning unit 43 causes the touch panel 32 to display a bird's eye view image in the moving direction and a plan view image on the parking search screen shown in fig. 3A. After acquiring at least one candidate parking space 60, the action planning unit 43 causes the touch panel 32 to display a frame representing the candidate parking space 60 and an icon 59 corresponding to the frame such that the frame and the icon 59 are superimposed on at least one of the above surrounding images (i.e., at least one of the overhead image and the bird's eye view image). The icon is composed of a symbol (see "P" in fig. 3A) representing a candidate parking slot 60. Further, the action planning unit 43 displays a notification on the parking search screen of the touch panel 32, instructs the driver to stop the vehicle and set the parking position (target parking space 53), and receives a selection operation of the target parking space 53. The selection operation of the target parking space 53 may be performed via the touch panel 32, or may be performed via the selection input member 35.

Next, after the driver selects the target parking space 53, the action planning unit 43 performs a trajectory calculation process (ST3) to calculate a trajectory of the vehicle to the target parking space 53. Incidentally, in the case where the trajectory to the target parking space 53 cannot be calculated, the action planning unit 43 may return to step ST1 and issue again a notification instructing the driver to move the vehicle straight. In addition, when the trajectory to the target parking space 53 cannot be calculated after the plurality of candidate parking spaces 60 are acquired, the action planning unit 43 may receive the selection of a new target parking space 53 by displaying the candidate parking spaces 60 other than the candidate parking space 60 selected by the driver on the touch panel 32. When a new target parking space 53 is selected, the action planning unit 43 may calculate the trajectory of the vehicle to the target parking space 53 again.

When the calculation of the trajectory of the vehicle to the target parking space 53 is completed, the action planning unit 43 causes the touch panel 32 to switch the screen from the parking search screen to the parking screen. As shown in fig. 3B, the parking screen is a screen in which a moving direction image (a front image or a rear image) in the vehicle moving direction is displayed on the right half of the touch panel 32, and a plan view image including the vehicle and its surrounding area is displayed on the left half of the touch panel 32. At this time, the action planning unit 43 may cause the touch panel 32 to display a thick frame indicating the target parking space 53 selected from the candidate parking spaces 60 so that the thick frame is superimposed on the overhead image.

After the screen of the touch panel 32 is switched to the parking screen, the action planning section 43 executes a driving process (step ST4) to move the vehicle along the calculated trajectory. At this time, the action planning unit 43 controls the vehicle so that the vehicle moves along the calculated trajectory based on the vehicle position acquired by the GPS receiving unit 20 and signals from the external camera 19, the vehicle sensor 8, and the like. At this time, the action planning unit 43 controls the powertrain 4, the brake device 5, and the steering device 6 so as to perform a switching operation for switching the moving direction of the vehicle (a reverse operation for reversing the moving direction of the vehicle). The switching operation may be repeatedly performed or may be performed only once.

During the driving process, the action planning unit 43 may acquire the movement direction image from the external camera 19 and cause the touch panel 32 to display the acquired movement direction image on the right half thereof. For example, as shown in fig. 3B, when the vehicle moves backward, the action planning unit 43 may cause the touch panel 32 to display an image behind the vehicle captured by the external camera 19 on the right half thereof. When the action planning unit 43 is executing the driving process, the surrounding image of the vehicle (own vehicle) in the overhead image displayed on the left half portion of the touch panel 32 changes with the movement of the vehicle. When the vehicle reaches the target parking space 53, the action planning unit 43 stops the vehicle and ends the driving process.

When the vehicle state determination unit 46 determines that the vehicle is in the prohibition state during the driving process, the action planning unit 43 displays a notification that the automatic parking is suspended or canceled on the touch panel 32, and executes the deceleration process to decelerate the vehicle, thereby stopping the vehicle. Therefore, when the occupant inputs a predetermined operation via the operation input member 11, the action planning unit 43 executes the deceleration process, whereby it is possible to avoid the discomfort that would be caused to the occupant if the vehicle continues to move.

When the driving process ends, the action planning unit 43 executes the parking process (step ST 5). In the parking process, the action planning unit 43 first drives the shift actuator 17 to set the shift position (shift range) to the parking position (parking range). Thereafter, the action planning unit 43 drives the parking brake device, and causes the touch panel 32 to display a pop-up window indicating completion of the automatic parking of the vehicle (see fig. 3C). The pop-up window may be displayed on the screen of the touch panel 32 for a prescribed period of time. Thereafter, the action planning section 43 may cause the touch panel 32 to switch the screen to the operation screen or the map screen of the navigation device 10.

In the parking process, there may be a case where the shift position cannot be changed to the parking position due to an abnormality of the shift actuator 17 or a case where the parking brake device cannot be driven due to an abnormality of the parking brake device. In these cases, the action planning unit 43 may cause the touch panel 32 to display the cause of the abnormality on the screen thereof.

Next, the extraction process will be described in more detail. In the extraction process, the action planning unit 43 acquires the position of the parking space line 55 from the external environment recognition unit 41, determines the parking type including the oblique parking and the vertical parking, and sets at least one parking space candidate 60. To execute such processing, as shown in fig. 1, the action planning unit 43 includes a virtual line calculation unit 61, an angle calculation unit 62, a parking type determination unit 63, and a parking position candidate setting unit 64, which are functional units.

The virtual line calculation unit 61 acquires the moving direction image and the parking position line 55 from the external camera 19. When two or more parking bit lines 55 cannot be acquired, the virtual line calculation unit 61 does not calculate the virtual line 57. When three or more parking spots 55 can be acquired, the virtual line calculation unit 61 calculates a virtual line 57 connecting the roadway-side ends (i.e., the ends on one side of the roadway 56) of the parking spots 55 adjacent to each other. The dummy line calculation unit 61 may calculate the dummy line 57 by connecting a roadway-side end of one parking space line 55 (hereinafter referred to as "second parking space line 55B") and a roadway-side end of the other parking space line 55 (hereinafter referred to as "third parking space line 55C"). The second parking space line 55B is a parking space line 55 arranged second from the vehicle toward the moving direction thereof, and the third parking space line 55C is a parking space line 55 arranged third from the vehicle toward the moving direction thereof. That is, the second and third parking bit lines 55B and 55C are adjacent to each other.

At this time, the virtual line calculation unit 61 may calculate line segments connecting the roadway-side ends of the two adjacent parking spots 55 of each combination of the parking spots 55, and determine whether the calculated line segments are located on substantially the same straight line. At this time, the virtual line calculation unit 61 may also determine whether the line segments have substantially the same length. When the line segments are located on substantially the same straight line and have substantially the same length, the virtual line calculation unit 61 may output one of the line segments as the virtual line 57.

The angle calculation unit 62 calculates the parking angle δ by using the angle θ between the virtual line 57 and the parking position line 55 calculated by the virtual line calculation unit 61. More specifically, when the virtual line 57 calculated by the virtual line calculation unit 61 connects the roadway-side end of the second parking space line 55B and the roadway-side end of the third parking space line 55C, the angle calculation unit 62 calculates the angle θ between the second parking space line 55B or the third parking space line 55C and the virtual line 57, and sets the calculated angle θ as the parking angle δ.

When three or more parking bit lines 55 are acquired by the virtual line calculation unit 61 and the parking angle δ calculated by the angle calculation unit 62 is within a prescribed first angle range, the parking type determination unit 63 determines the parking type as the oblique parking. On the other hand, when three or more parking bit lines 55 are acquired by the virtual line calculation unit 61 and the parking angle δ is within the prescribed second angle range, the parking type determination unit 63 determines the parking type as vertical parking. The first angle range is a prescribed angle range greater than 0 degrees and less than 90 degrees. In the present embodiment, the first angle range includes: a prescribed angular range including 45 degrees (an angular range between 45 ± 5 degrees); and another prescribed angular range including 60 degrees (an angular range between 60 ± 5 degrees). The second angular range includes 90 degrees and excludes the first angular range. In the present embodiment, the second angle range is set to a predetermined angle range including 90 degrees (an angle range between 90 ± 5 degrees).

In a case where the dummy line calculation unit 61 acquires only two or less parking space lines 55 (for example, the dummy line calculation unit 61 does not acquire the parking space lines 55 and thus does not calculate the dummy lines 57), the parking type determination unit 63 does not determine the parking type.

The parking space candidate setting unit 64 sets at least one rectangular temporary parking space 52X in the region between the parking spaces 55 based on the position of the parking space 55. Temporary parking space 52X is a space that may be a candidate parking space 60. More specifically, the parking space candidate setting unit 64 first sets the temporary parking space 52X between two adjacent parking spaces 55 arranged in front of the vehicle.

Incidentally, when the parking type is the oblique parking, the parking space candidate setting unit 64 sets the temporary parking space 52X so that the vehicle is parked farther from the roadway 56 than the roadway-side ends of the two parking spaces 55. More specifically, the parking space candidate setting unit 64 calculates straight lines L1 and L2 that pass through the roadway-side ends of the two parking spaces 55 and are arranged orthogonal to the extending direction of the two parking spaces 55. Thereafter, the parking space candidate setting unit 64 selects a far-side straight line (a straight line farther from the roadway 56; i.e., L2) from the two straight lines L1 and L2, and sets the temporary parking space 52X at a position farther from the roadway 56 than the far-side straight line. Alternatively, the candidate parking space setting unit 64 may set the temporary parking space 52X such that the roadway-side end portion of the temporary parking space 52X (i.e., the end portion of one side of the roadway 56) matches the far-side straight line (i.e., L2) of the two straight lines L1 and L2. Alternatively, the parking space candidate setting unit 64 may estimate the start position of the two parking spaces 55 in front in the extending direction thereof (the position at which the vehicle starts moving backward, see the two-dot chain line in fig. 4), and set the temporary parking space 52X such that the position of the temporary parking space 52X is further rearward than the start position and the roadway-side ends of the two parking spaces 55.

On the other hand, when the parking type is vertical parking, the parking space candidate setting unit 64 sets the temporary parking space 52X such that the roadway-side end portion of the parked vehicle (i.e., the end portion of one side of the roadway 56) matches one of the roadway-side end portions of the two parking spaces 55 that is closer to the roadway 56. More specifically, the parking position candidate setting unit 64 calculates straight lines M1 and M2 that pass through the roadway-side ends of the two parking positions 55 and are arranged orthogonally to the extending direction of the two parking positions 55. Thereafter, the parking space candidate setting unit 64 may set the temporary parking space 52X such that the roadway-side end of the temporary parking space 52X matches the near-side straight line of the two straight lines M1 and M2 (the straight line closer to the roadway 56; i.e., M1). Alternatively, the parking space candidate setting unit 64 may estimate the starting positions of the two parking spaces 55 in the front in the extending direction thereof (the positions at which the vehicle starts moving backward; see the two-dot chain line in fig. 5A), and set the temporary parking space 52X such that the roadway-side end of the vehicle is positioned further backward than the starting positions and matches the ends of the two parking spaces 55.

In addition, when the virtual line calculation unit 61 acquires only the two parking lines 55 (as in the case where the parking type is vertical parking), the parking space candidate setting unit 64 sets the temporary parking space 52X such that the road-side end of the parked vehicle matches one of the road-side ends of the two parking lines 55 that is closer to the road 56.

Next, the candidate parking space setting unit 64 performs a determination process to determine whether each temporary parking space 52X is suitable for the candidate parking space 60. In the determination process, when it is determined that the temporary parking place 52X is suitable for the candidate parking place 60, the candidate parking place setting unit 64 outputs the temporary parking place 52X as the candidate parking place 60. Incidentally, when the parking type cannot be determined by the parking type determining unit 63, the candidate parking space setting unit 64 makes an output corresponding to the fact that the candidate parking space 60 cannot be set.

More specifically, in the determination process in the case where the parking type determined by the parking type determination unit 63 is the oblique parking, the parking space candidate setting unit 64 determines that the temporary parking space 52X (hereinafter referred to as "the latest temporary parking space 52X") set between one parking space line 55 (hereinafter referred to as "first parking space line 55A") and the second parking space line 55B is not suitable for the parking space candidate 60. The first parking position line 55A is the parking position line 55 closest to the vehicle. In addition, the candidate parking space setting unit 64 determines whether at least one temporary parking space 52X other than the latest temporary parking space 52X is suitable for the candidate parking space 60 based on the signal from the external camera 19 and/or the sonar 18. In the case where there is no obstacle for the movement and parking of the vehicle (for example, no obstacle is detected in the temporary parking space 52X), the candidate parking space setting unit 64 determines that the vehicle can be parked in the temporary parking space 52X (i.e., the temporary parking space 52X is suitable for the candidate parking space 60). On the other hand, in the case where there is an obstacle to the movement or parking of the vehicle, the candidate parking space setting unit 64 determines that the vehicle cannot be parked in the temporary parking space 52X (i.e., the temporary parking space 52X is not appropriate for the candidate parking space 60).

In the determination process in the case where the parking type determined by the parking type determination unit 63 is the vertical parking, the parking space candidate setting unit 64 includes the latest temporary parking space 52X in the temporary parking spaces 52X for which the above-described suitability determination is made. In the case where there is no obstacle for the movement and parking of the vehicle (for example, no obstacle is detected in the temporary parking space 52X), the candidate parking space setting unit 64 determines that the temporary parking space 52X is suitable for the candidate parking space 60. On the other hand, in the case where there is an obstacle to the movement or parking of the vehicle, the parking space candidate setting unit 64 determines that the temporary parking space 52X is not appropriate for the parking space candidate 60.

Next, the extraction process performed by the action planning unit 43 will be described with reference to fig. 6. In the first step ST11 of the extraction process, the action planning unit 43 (more specifically, the virtual line calculation unit 61) acquires (extracts) the moving direction image and the parking space line 55. After completion of the acquisition, the action planning unit 43 executes step ST 12.

In step ST12, the action planning unit 43 (virtual line calculation unit 61) determines whether three or more parking bitlines 55 have been acquired. When three or more parking lines 55 are acquired, the action planning unit 43 executes step ST 13. When the three or more parking lines 55 are not acquired, the action planning unit 43 executes step ST 14.

In step ST13, the action planning means 43 (virtual line calculation means 61) calculates a virtual line 57 connecting the roadway-side ends of the parking spaces 55 adjacent to each other. After the calculation is completed, the action planning unit 43 executes step ST 15.

In step ST14, the action planning unit 43 (virtual line calculation unit 61) determines whether two parking bitlines 55 have been acquired. When the two parking lines 55 are acquired, the action planning unit 43 executes step ST 16. When the two parking lines 55 are not acquired, the action planning unit 43 executes step ST 17.

In step ST15, the action planning unit 43 (angle calculation unit 62) determines the angle θ between the parking position line 55 and the virtual line 57 (i.e., the parking angle δ). Next, the action planning unit 43 (parking type determining unit 63) determines whether the angle θ (i.e., the parking angle δ) is within a first angle range (i.e., one angle range between 45 ± 5 degrees or another angle range between 60 ± 5 degrees). In the case where the angle θ (parking angle δ) is within the first angle range, the action planning unit 43 determines that the parking type is the oblique parking, and executes step ST 18. When the angle θ (parking angle δ) is out of the first angle range, the action planning unit 43 executes step ST 19.

In step ST16, the action planning unit 43 (parking space candidate setting unit 64) sets the temporary parking space 52X between the two parking levels 55. In the present embodiment, as in the case where the parking type is vertical parking, the action planning unit 43 (parking space candidate setting unit 64) sets the temporary parking space 52X such that the roadway-side end of the parked vehicle matches one of the roadway-side ends of the two parking spaces 55 that is closer to the roadway 56. After that, the action planning unit 43 (parking space candidate setting unit 64) executes the determination process of the temporary parking space 52X. If the temporary parking space 52X is suitable for the candidate parking space 60, the action planning unit 43 sets the temporary parking space 52X as the candidate parking space 60 and ends the extraction process.

In step ST17, the action planning unit 43 (parking space candidate setting unit 64) determines that the parking space candidate 60 cannot be acquired (the parking space candidate 60 does not exist), and ends the extraction processing.

In step ST18, the action planning unit 43 (parking space candidate setting unit 64) sets the temporary parking space 52X between the two parking levels 55. At this time, since the parking type is the oblique parking, the action planning unit 43 sets the temporary parking space 52X so that the vehicle is parked farther from the roadway 56 than the roadway-side ends of the two parking levels 55 (see fig. 4). After that, the action planning unit 43 (parking space candidate setting unit 64) executes determination processing regarding each temporary parking space 52X. At this time, it is determined that the latest temporary parking space 52X (i.e., the temporary parking space 52X of the closest vehicle) is not suitable for the candidate parking space 60. Thus, the action planning unit 43 (parking space candidate setting unit 64) extracts the available temporary parking space 52X (i.e., the temporary parking space 52X in which the vehicle can be parked) from at least one temporary parking space 52X arranged further forward than the vehicle body and the latest temporary parking space 52X (i.e., at least one temporary parking space 52X excluding the latest temporary parking space 52X). Then, the action planning unit 43 sets the extracted temporary parking slot 52X as the candidate parking slot 60, and ends the extraction process.

In step ST19, the action planning unit 43 (angle calculation unit 62) determines the parking angle δ. Next, the action planning unit 43 (parking type determining unit 63) determines whether the angle θ (parking angle δ) is within a second angle range (i.e., an angle range between 90 ± 5 degrees). In the case where the angle θ is within the second angle range, the action planning unit 43 determines that the parking type is the vertical parking, and executes step ST 20. In the case where the angle θ is outside the second angle range, the action planning unit 43 determines that the parking type is unknown, and executes step ST 16.

In step ST20, the action planning unit 43 (parking space candidate setting unit 64) sets the temporary parking space 52X between the two parking levels 55. At this time, since the parking type is vertical parking, the action planning unit 43 sets the temporary parking slot 52X such that the lane-side end of the parked vehicle matches one of the ends of the two parking levels 55 that is closer to the lane 56. After that, the action planning unit 43 (parking space candidate setting unit 64) executes the determination process for each temporary parking space 52X. At this time, in a case where the vehicle can be parked in the latest temporary parking space 52X, the latest temporary parking space 52X is determined to be suitable for the candidate parking space 60. That is, the action planning unit 43 (parking space candidate setting unit 64) extracts the available temporary parking space 52X (i.e., the temporary parking space 52X in which the vehicle can be parked) from at least one temporary parking space 52X arranged further forward than the vehicle body (i.e., at least one temporary parking space 52X including the latest temporary parking space 52X). Then, the action planning unit 43 sets the extracted temporary parking slot 52X as the candidate parking slot 60, and ends the extraction process.

When the extraction process is completed, the action planning unit 43 ends the acquisition process, and executes the target parking position reception process. At this time, when the parking candidate slot 60 has been acquired, the action planning unit 43 displays the parking candidate slot 60 on the touch panel 32 and receives the selection operation of the target parking slot 53. In a case where the candidate parking place 60 is not acquired (for example, in a case where the candidate parking place 60 does not exist in step ST 17), the action planning unit 43 causes the touch panel 32 to display that the candidate parking place 60 is not found. Alternatively, the action planning unit 43 may cause the touch panel 32 to display to continue searching for the candidate parking space 60 without causing the touch panel 32 to display the candidate parking space 60 or displaying that the candidate parking space 60 is not found.

Next, the effects of the parking assist system 1 configured in this manner will be described. In steps ST15 and ST19, the parking type of the vehicle is determined based on the virtual line 57 and the parking bit line 55. Therefore, the parking type is determined not based on the moving direction of the vehicle but based on the shape of the parking bit line 55, so that erroneous recognition of the parking type can be prevented.

Even if only two parking spaces 55 are identified (yes in ST 14), the temporary parking space 52X may be set between the parking spaces 55. Therefore, the candidate parking space 60 is more easily provided, thereby improving the convenience of the vehicle.

In steps ST16, ST18, and ST20, at least one temporary parking space 52X is set between the parking levels 55, and a target parking space 53 is selected from the temporary parking spaces 52X. That is, the parking space recognition system S (including the control device 15 and the external environment sensor 7 (external camera 19)) recognizes the parking space 52 for parking the vehicle between the parking spaces 55, and the control device 15 includes a virtual line calculation unit 61, an angle calculation unit 62, a parking type determination unit 63, and a parking space candidate setting unit 64.

In the case where only two parking spots 55 are recognized, the parking spots 55 in the parking lot tend to have faded. In this case, the end of the parking line 55 may be blurred and may not be accurately recognized, and thus the position of the temporary parking space 52X may not be accurately determined. Therefore, when the temporary parking space 52X is set such that the roadway-side end of the parked vehicle matches one of the roadway-side ends of the two parking levels 55 that is farther from the roadway 56, the parking position of the vehicle may be excessively offset rearward.

In this case, in the present embodiment, as in the case where the parking type is the vertical parking, the temporary parking space 52X is set such that the roadway-side end of the parked vehicle matches one of the roadway-side ends of the two parking levels 55 that is closer to the roadway 56. Therefore, the parking position of the vehicle is prevented from being excessively shifted rearward, and the safety of the vehicle is improved.

The parking type is determined based on whether the angle θ between the virtual line 57 and the parking line 55 (i.e., the parking angle δ) is within the first angle range or the second angle range. Therefore, for example, the determination of the parking type becomes simple as compared with the case where the parking line 55 is recognized and the parking type is determined by means of a method such as pattern matching.

The parking angle δ of the oblique parking spot 52A (i.e., the parking spot 52 for oblique parking; see fig. 4) is generally set to 45 degrees or 60 degrees. In the present embodiment, the first angle range is set to an angle range between 45 ± 5 degrees and 60 ± 5 degrees. Therefore, when the roadway-side end of the parking spot line 55 of the vertical parking spot 52B (i.e., the parking spot 52 for vertical parking; see FIGS. 5A and 5B) is blurred and its position cannot be recognized, it is possible to prevent the vertical parking from being erroneously recognized as the oblique parking.

Further, as shown in fig. 4, in a parking lot where the oblique parking spaces 52A are provided, a zebra zone 80 for preventing the vehicle from entering and parking is often provided outside the parking spaces 55 at both ends among the parking spaces 55 arranged at regular intervals. Therefore, it is often difficult to recognize the roadway-side end of the closest parking space 55 of the vehicle (i.e., the parking space 55 closest to the vehicle) immediately after the vehicle enters such a parking lot. Therefore, when performing an angled parking, the area between the closest parking line 55 and its adjacent parking line 55 is often not suitable for automatic parking of the vehicle. In the present embodiment, as shown in fig. 6, when the parking type is an oblique parking (step ST 15: yes), the action planning unit 43 sets the temporary parking space 52X in a region other than a region between the closest parking space 55 (first parking space 55A) and its adjacent parking space 55 (second parking space 55B). Thereafter, the action planning unit 43 sets the parking candidate slot 60 by extracting the available temporary parking slot 52X from the set temporary parking slots 52X (ST 18). Therefore, it is possible to prevent the region unsuitable for the parking position from being set as the parking candidate space 60.

On the other hand, in the parking lot provided with the vertical parking spaces 52B, the zebra regions 80 are not often provided outside the parking lines 55 at both ends among the parking lines 55 arranged at regular intervals, as compared with the parking lot provided with the oblique parking spaces 52A. In the present embodiment, when the parking type is vertical parking (step ST 19: yes), the parking space candidate setting unit 64 sets the temporary parking space 52X such that the area between the closest parking space line 55 (first parking space line 55A) and its adjacent parking space line 55 (second parking space line 55B) is included in the temporary parking space 52X to be extracted as the parking space candidate 60. Therefore, a large number of temporary parking spaces 52X can be set (step ST 20). Thus, a greater variety of candidate parking slots 60 may be provided to the user so that the user may move the vehicle to a desired location and park the vehicle therein.

The specific embodiments of the present invention have been described above, but the present invention should not be limited by the foregoing embodiments, and various modifications and alterations can be made within the scope of the present invention. For example, the specific structure, arrangement, number, processing content, program, and the like of the components/units of the embodiments may be appropriately changed within the scope of the present invention. In addition, not all the structural elements shown in the above embodiments are indispensable, and they may be selectively employed as appropriate.

In the present embodiment, the action planning means 43 calculates the virtual line 57, and acquires the parking angle δ based on the virtual line 57. However, the present invention is not limited to this embodiment. For example, in a case where three or more parking spots 55 and the extending direction of the roadway 56 can be recognized, the action planning unit 43 may first determine whether all angles between the respective parking spots 55 and the extending direction of the roadway 56 are the same. After that, the action planning unit 43 may set the assumed angle as the parking angle δ when the interval between the parking spots 55 is constant on the assumption that each of the parking spots 55 forms an angle of 45 degrees or 60 degrees with respect to the extending direction of the roadway 56.

In the present embodiment, when one white line is captured by the external camera 19, the external environment recognition unit 41 recognizes the captured one white line as one parking bit line 55. However, the present invention is not limited to this embodiment. When the external camera 19 captures two or more white lines within the prescribed range, the external environment recognition unit 41 may recognize one parking bit line 55 by regarding the two or more white lines as one white line.

In the present embodiment, the parking assist system 1 autonomously moves the vehicle and parks the vehicle in the parking space based on the determination results such as the candidate parking space 60 set by the candidate parking space setting unit 64 and the parking type determined by the parking type determination unit 63. However, the present invention is not limited to this embodiment. The parking assist system 1 may have only the functions of determining the parking type and detecting the candidate parking space 60. However, if the parking assist system 1 is capable of autonomously moving the vehicle and parking the vehicle in a parking position, the convenience of the vehicle can be improved. In addition, in the present embodiment, the control device 15 is provided with a virtual line calculation unit 61, an angle calculation unit 62, a parking type determination unit 63, and a parking position candidate setting unit 64. However, the present invention is not limited to this embodiment. The virtual line calculation unit 61, the angle calculation unit 62, the parking type determination unit 63, and the parking position candidate setting unit 64 may be provided in a device (parking position candidate detection device) different from the control device 15.

In the present embodiment, the angle θ between the dummy line 57 and the parking bit line 55 represents a small angle therebetween, and is defined as an angle equal to or greater than 0 degrees and equal to or less than 90 degrees. However, the present invention is not limited to this embodiment. An angle θ between the dummy line 57 and the parking bit line 55 may be defined as an angle equal to or greater than 0 degrees and less than 180 degrees. In this case, the first angle range may be defined as one prescribed angle range including 45 degrees or 135 degrees and another prescribed angle range including 60 degrees or 120 degrees, and the second angle range may be defined as a range including 90 degrees and excluding the first angle range. In this case, as in the present embodiment, when three or more parking lines 55 are recognized and the angle θ (i.e., the parking angle δ) is within the first angle range, the parking type determination unit 63 may determine the parking type as the oblique parking. In addition, when three or more parking lines 55 are recognized and the angle θ (i.e., the parking angle δ) is within the second angle range, the parking type determination unit 63 may determine the parking type as the vertical parking.