JP2019156308A - Parking support device - Google Patents

Abstract

To provide a parking support device which can park a vehicle in a further proper position in a parking region when guiding the vehicle on the basis of a compartment line which is recognized from a photographed image.SOLUTION: A parking support device comprises: a setting part for setting a movement target position of a vehicle within a parking region included in an image which is photographed by a photographing part; a position acquisition part for acquiring a current position of the vehicle; a guide control part for guiding the vehicle to the movement target position on the basis of the movement target position and the current position; a comparison part for comparing a first angle which is formed of a first direction passing the movement target position, and extending along an extension direction of a compartment line and a second direction extending along a fore-and-aft direction of the vehicle, and a preset second angle; a recognition part for recognizing a compartment line near the vehicle out of a pair of compartment lines on an image when the first angle is larger than the second angle, and recognizing both the pair of compartment lines on the image when the first angle is equal to or less than the second angle; and a correction part for correcting at least either of the movement target position or the current position of the vehicle according to a recognition result of the compartment lines.SELECTED DRAWING: Figure 6

Description

  Embodiments described herein relate generally to a parking assistance device.

  2. Description of the Related Art Conventionally, a parking support device that supports a parking operation of a vehicle in a parking lot or the like is known. For example, when a parking assistance apparatus guides and parks a vehicle in a parking area that is partitioned by a lane marking (for example, a pair of white lines) in a parking lot, first, the parking assistance device is parked based on a captured image around the vehicle. Search and present possible parking area candidates. When a parking area is selected from the candidates by the driver or the system, a movement target position (parking target position) is set in the selected parking area, and the movement target position is reached from the current position of the vehicle. The movement route for making it go is calculated. As a result, the driver or the system can move the vehicle by guidance according to the movement route. The parking assist device monitors the vehicle so as to reach the movement target position along the movement path while estimating the current position of the vehicle as needed based on the captured image and detection signals from the wheel speed sensor, the steering angle sensor, and the like. . In addition, for example, the parking assistance device detects a lane line from the captured image at any time during the parking assistance, and corrects the movement target position and the like based on the detected lane line.

Japanese Patent No. 4235026

  In the case of the parking assistance device described above, during parking assistance, regardless of the distance from the vehicle to the lane marking and the attitude of the vehicle relative to the lane marking, what is deemed to be a lane marking or lane marking from the captured image at any time, Based on the detection result, the movement target position, the movement route, and the like are corrected. However, when the position of the vehicle is far from the lane line, the lane line that appears on the image is small, or depending on the vehicle's posture, the lane line may be difficult to see on the image, and the lane line cannot be accurately recognized (recognition). The accuracy may be low), and the recognition accuracy may differ for each lane marking. In that case, the tip of the lane marking cannot be identified, or the direction (angle) in which the lane marking extends cannot be detected accurately. As a result, the width, depth, etc. (width) of the parking area cannot be accurately detected, and the movement target position, movement route, etc. are corrected to an inappropriate state. For example, the parking area is inclined with respect to the parking area. In some cases, the vehicle was guided in a different posture.

  Therefore, one of the problems of the embodiment is to provide a parking assist device that can park at a more appropriate position in the parking area when the vehicle is guided based on the lane marking recognized from the captured image. is there.

  The parking assist device according to the embodiment of the present invention is, for example, in a parking area defined by a pair of lane markings arranged apart from each other, which is included in an image output from an imaging unit that images the surrounding situation of a vehicle. A setting unit for setting the movement target position of the vehicle, a position acquisition unit for acquiring the current position of the vehicle, and guidance for guiding the vehicle to the movement target position based on the movement target position and the current position. A first angle formed by a control unit, a first direction passing through the movement target position and extending along the extending direction of the lane marking, and a second direction extending along the longitudinal direction of the vehicle; A comparison unit that compares a second angle set in advance, and a section closer to the vehicle among the pair of lane lines on the image when the first angle is larger than the second angle. Recognize the line and the first angle is the second angle A recognition unit for recognizing both of the pair of lane markings on the image and at least one of the movement target position or the current position of the vehicle according to the recognition result of the lane markings when the angle is less than A correction unit.

  According to this configuration, when the first angle is larger than the second angle, for example, it can be considered that the posture of the vehicle is greatly inclined with respect to the first direction. In this case, on the image, there are lane lines whose relative distance from the vehicle is close and easy to be recognized accurately, and lane lines whose recognition accuracy is lower than that of a lane line whose relative distance from the vehicle is far and close to the vehicle. . In such a case, a near lane marking with relatively high recognition accuracy is recognized, and at least one of the movement target position or the current position of the vehicle is corrected based on the lane marking. As a result, it is possible to reduce the fact that the recognition result of the lane markings with low recognition accuracy is reflected in the parking assistance by affecting the correction accuracy of the movement target position and the current position of the vehicle. On the other hand, when the first angle is equal to or smaller than the second angle, it can be considered that the inclination of the vehicle front-rear direction (second direction) with respect to the first direction is small. That is, it can be considered that the difference in relative distance from the vehicle to the pair of lane markings that define the parking area is small, and the difference in recognition accuracy between the pair of lane markings is small. In such a case, both lane markings can be handled in the same way, and therefore the width of the parking area and the depth of the parking area, such as the width of the parking area, can be more accurately determined based on the recognition result of both lane markings. it can. That is, the correction accuracy of the movement target position and the current position of the vehicle can be improved. As a result, it is possible to prevent the vehicle from being guided toward one of the lane markings in the parking area or guided in a tilted position within the parking area. Can be parked in position.

  The said guidance control part of the parking assistance apparatus concerning embodiment of this invention may display the parameter | index which shows the said parking area on a display apparatus based on the said movement target position and the said present position, for example. According to this configuration, a more accurate parking area can be provided to the driver.

  The parking assist device according to the embodiment of the present invention further includes a route acquisition unit that acquires a movement route for moving the vehicle based on the movement target position and the current position, for example, The vehicle may be guided to the movement target position according to the movement route based on the movement target position and the current position. According to this configuration, for example, the movement route can be acquired based on the movement target position based on the lane marking with higher recognition accuracy and the current position of the vehicle. As a result, it is possible to prevent the vehicle from being guided toward one of the lane markings or guided in a tilted position within the parking area, and park the vehicle at a more appropriate position within the parking area. be able to.

  For example, the comparison unit of the parking assistance device according to the embodiment of the present invention may execute the comparison process when the distance from the movement target position to the vehicle is a predetermined value or less. According to this configuration, for example, when the distance from the movement target position to the vehicle (the vehicle) is long and it is difficult to expect improvement in the recognition accuracy of the lane line, the lane line recognition is temporarily suspended. That is, the correction of the movement target position and the current position of the vehicle is temporarily stopped, and it is possible to avoid the correction that the accuracy of the movement target position and the current position of the vehicle is lowered.

FIG. 1 is a schematic plan view illustrating an example of a vehicle on which the parking assist device according to the embodiment can be mounted. FIG. 2 is an exemplary block diagram of a configuration of a parking assistance system including the parking assistance device according to the embodiment. Drawing 3 is a figure showing an example in the case of performing parking assistance of vehicles with the parking assistance device concerning an embodiment, and is a bird's-eye view schematic diagram explaining notion of search of a parking area and guidance of a vehicle by a movement route. is there. FIG. 4 is a schematic diagram illustrating an example of an image captured by the imaging unit of the parking assistance device according to the embodiment. FIG. 5 is a schematic diagram illustrating a determination angle for determining whether or not to recognize a lane marking far from the vehicle by the parking assistance device according to the embodiment. FIG. 6 is an exemplary block diagram of a configuration of a CPU of the parking assistance device according to the embodiment. FIG. 7 is a flowchart illustrating an example of parking support processing by the parking support device according to the embodiment, in which the movement route is corrected by correcting the movement target position.

  Hereinafter, exemplary embodiments of the present invention are disclosed. The configuration of the embodiment shown below and the operations, results, and effects brought about by the configuration are examples. The present invention can be realized by configurations other than those disclosed in the following embodiments, and at least one of various effects based on the basic configuration and derivative effects can be obtained. .

  FIG. 1 is a schematic plan view of a vehicle 10 on which the parking assist device of the present embodiment is mounted. The vehicle 10 may be, for example, an automobile (an internal combustion engine automobile) using an internal combustion engine (engine, not shown) as a drive source, or an automobile (electric vehicle) using an electric motor (motor, not shown) as a drive source. Or a fuel cell vehicle or the like, or a vehicle (hybrid vehicle) using both of them as drive sources. Further, the vehicle 10 can be mounted with various transmissions, and various devices (systems, components, etc.) necessary for driving the internal combustion engine and the electric motor can be mounted. In addition, the system, number, layout, and the like of devices related to driving of the wheels 12 (front wheels 12F, rear wheels 12R) in the vehicle 10 can be set in various ways.

  As illustrated in FIG. 1, the vehicle 10 is provided with, for example, four imaging units 14 a to 14 d as the plurality of imaging units 14. The imaging unit 14 is a digital camera that incorporates an imaging element such as a charge coupled device (CCD) or a CMOS image sensor (CIS). The imaging unit 14 can output moving image data (captured image data) at a predetermined frame rate. The imaging unit 14 has a wide-angle lens or a fish-eye lens, respectively, and can capture a range of, for example, 140 ° to 220 ° in the horizontal direction. Further, the optical axis of the imaging unit 14 may be set obliquely downward. Therefore, the imaging unit 14 is a road surface on which the vehicle 10 is movable, an index (including a lane line indicating a parking area, a lane separation line, an arrow, or the like) or an object (as an obstacle, such as a pedestrian, The surrounding environment outside the vehicle 10 including the vehicle etc. is sequentially photographed and output as captured image data.

  The imaging unit 14 is provided on the outer periphery of the vehicle 10. The imaging unit 14a is provided at, for example, the rear side of the vehicle 10, that is, the rear side of the vehicle in the vehicle front-rear direction, at the substantially central end in the vehicle width direction, for example, above the rear bumper 10a. The rear region including the rear bumper 10a) can be imaged. Further, the imaging unit 14b is provided at, for example, the front side of the vehicle 10, that is, the front side in the vehicle front-rear direction and the substantially center end in the vehicle width direction, for example, the front bumper 10b, the front grill, or the like. A front image including (for example, the front bumper 10b) can be captured. Further, the imaging unit 14c is provided on, for example, the right end of the vehicle 10, for example, the right door mirror 10c, and includes a right side including a region centered on the right side of the vehicle 10 (for example, a region from right front to right rear). A square image can be captured. The imaging unit 14d is provided on, for example, the left end of the vehicle 10, for example, the left door mirror 10d, and includes a left side image including a region centered on the left side of the vehicle 10 (for example, a region from the left front to the left rear). Can be imaged.

  The parking assistance apparatus according to the present embodiment recognizes (detects) lane markings and the like by executing arithmetic processing and image processing based on captured image data (images) obtained by the plurality of imaging units 14. Can do. The parking support device searches for a parking area for parking the vehicle 10 based on recognition of the lane marking, sets a movement target position used when guiding the vehicle 10 to the parking area, and estimates the current position of the vehicle 10. In addition, it is possible to calculate a movement route for guiding the vehicle 10 to the movement target position. In addition, an image with a wider viewing angle is generated by executing arithmetic processing and image processing based on captured image data obtained by the plurality of imaging units 14, and the vehicle 10 is moved upward, forward, sideward, and the like. A virtual image viewed from above (a bird's-eye view image (planar image), a side view image, a front view image, etc.) can be generated.

  FIG. 2 is an exemplary block diagram of a configuration of a parking assistance system 100 including a parking assistance device mounted on the vehicle 10. A display device 16 and an audio output device 18 are provided in the passenger compartment of the vehicle 10. The display device 16 is, for example, an LCD (liquid crystal display) or an OELD (organic electroluminescent display). The audio output device 18 is, for example, a speaker. The display device 16 is covered with a transparent operation input unit 20 such as a touch panel, for example. An occupant (for example, a driver) can visually recognize an image displayed on the display screen of the display device 16 via the operation input unit 20. In addition, the occupant can perform an operation input by operating the operation input unit 20 by touching, pushing, or moving the operation input unit 20 with a finger or the like at a position corresponding to the image displayed on the display screen of the display device 16. it can. The display device 16, the audio output device 18, the operation input unit 20, and the like are provided, for example, in a monitor device 22 that is positioned in the vehicle width direction of the dashboard of the vehicle 10, that is, the central portion in the left-right direction. The monitor device 22 can have an operation input unit (not shown) such as a switch, a dial, a joystick, and a push button. The monitor device 22 can be used also as, for example, a navigation system or an audio system.

  As illustrated in FIG. 2, the parking support system 100 (parking support device) includes an ECU 24 (electronic control unit) in addition to the imaging unit 14 (14 a to 14 d) and the monitor device 22. In the parking assistance system 100, the ECU 24 and the monitor device 22 are electrically connected via an in-vehicle network 26 as an electric communication line. The in-vehicle network 26 is configured as a CAN (controller area network), for example. The ECU 24 can control various systems by sending a control signal through the in-vehicle network 26. For example, in the parking assistance system 100, the steering system 28, the steering angle sensor 30, the brake system 32, the drive system 34, the accelerator sensor 36, the shift sensor 38, the wheel speed sensor 40, etc. are provided in the vehicle in addition to the ECU 24, the monitor device 22, and the like. It is electrically connected via the network 26. The ECU 24 can control the steering system 28, the brake system 32, the drive system 34, and the like by sending a control signal through the in-vehicle network 26. The ECU 24 also detects the detection results of the torque sensor 28a, the brake sensor 32a, the rudder angle sensor 30, the accelerator sensor 36, the shift sensor 38, the wheel speed sensor 40, and the like and the operation of the operation input unit 20 and the like via the in-vehicle network 26. You can receive signals, etc.

  The ECU 24 includes, for example, a CPU 24a (central processing unit), a ROM 24b (read only memory), a RAM 24c (random access memory), a display control unit 24d, an audio control unit 24e, an SSD 24f (solid state drive, flash memory), and the like. ing. For example, the CPU 24a determines the target position of the vehicle 10 when performing parking support, estimates the current position of the vehicle 10, calculates the movement distance, calculates the target vehicle speed and the target position for each time, and displays the display device. Various arithmetic processing and control such as image processing related to the image displayed at 16 can be executed.

  The CPU 24a can read a program installed and stored in a non-volatile storage device such as the ROM 24b and execute arithmetic processing according to the program. The ROM 24b stores each program and parameters necessary for executing the program. The RAM 24c temporarily stores various types of data used in computations by the CPU 24a. The display control unit 24d mainly executes image processing using the image data obtained by the imaging unit 14, synthesis of image data displayed on the display device 16, etc., among the arithmetic processing in the ECU 24. In addition, the voice control unit 24e mainly performs processing of voice data output from the voice output device 18 among the calculation processes in the ECU 24. The SSD 24f is a rewritable nonvolatile storage unit, and can store data even when the power of the ECU 24 is turned off. Note that the CPU 24a, the ROM 24b, the RAM 24c, and the like can be integrated in the same package. Further, the ECU 24 may have a configuration in which another logical operation processor such as a DSP (digital signal processor) or a logic circuit is used instead of the CPU 24a. Further, an HDD (hard disk drive) may be provided in place of the SSD 24f, and the SSD 24f and the HDD may be provided separately from the ECU 24.

  As illustrated in FIG. 1, the vehicle 10 is, for example, a four-wheel vehicle, and includes two left and right front wheels 12 </ b> F and two right and left rear wheels 12 </ b> R. Any of these four wheels 12 can be configured to be steerable. As illustrated in FIG. 2, the steering system 28 steers at least two wheels 12 of the vehicle 10. The steering system 28 includes a torque sensor 28a and an actuator 28b. The steering system 28 is electrically controlled by the ECU 24 or the like to operate the actuator 28b. The steering system 28 is, for example, an electric power steering system, an SBW (steer by wire) system, or the like. The steering system 28 adds torque, that is, assist torque to a steering part (for example, a steering wheel) by the actuator 28b to supplement the steering force, or steers the wheel 12 by the actuator 28b. In this case, the actuator 28b may steer one wheel 12 or may steer a plurality of wheels 12. Moreover, the torque sensor 28a detects the torque which a driver | operator gives to a steering part, for example.

  The steering angle sensor 30 is, for example, a sensor that detects the steering amount of the steering unit. The rudder angle sensor 30 is configured using, for example, a hall element. The ECU 24 obtains the steering amount of the steering unit by the driver, the steering amount of each wheel 12 during automatic steering, and the like from the steering angle sensor 30 and executes various controls. The rudder angle sensor 30 detects the rotation angle of the rotating part included in the steering unit.

  The brake system 32 is, for example, an anti-lock brake system (ABS) that suppresses the locking of the brake, a skid prevention device (ESC: electronic stability control) that suppresses the skidding of the vehicle 10 during cornering, and increases the braking force ( Electric brake system that executes brake assist, BBW (brake by wire), etc. The brake system 32 applies a braking force to the wheels 12 and thus to the vehicle 10 via the actuator 32b. In addition, the brake system 32 can execute various controls by detecting brake lock, idle rotation of the wheel 12, signs of skidding, and the like from the rotation difference between the left and right wheels 12. The brake sensor 32a is, for example, a sensor that detects the position of a movable part of a braking operation part (for example, a brake pedal).

  The drive system 34 is an internal combustion engine (engine) system or a motor system as a drive source. The drive system 34 controls the fuel injection amount and intake air amount of the engine and the output value of the motor in accordance with the requested operation amount (for example, the depression amount of the accelerator pedal) of the driver (user) detected by the accelerator sensor 36. . Further, the engine and motor output values can be controlled in cooperation with the control of the steering system 28 and the brake system 32 in accordance with the traveling state of the vehicle 10 regardless of the operation of the user. The same applies when the vehicle 10 is traveling in the automatic travel mode.

  The accelerator sensor 36 is, for example, a sensor that detects the position of a movable part of an acceleration operation part (for example, an accelerator pedal). The accelerator sensor 36 can detect the position of an accelerator pedal as a movable part.

  The shift sensor 38 is, for example, a sensor that detects the position of a movable part of a speed change operation part (for example, a shift lever). The shift sensor 38 can detect the position of a lever, an arm, a button, etc. as a movable part. The shift sensor 38 may include a displacement sensor or may be configured as a switch. Based on the detection result of the shift sensor 38, the ECU 24 can determine whether the vehicle 10 has received a forward travel request or a reverse travel request.

  The wheel speed sensor 40 is a sensor that is provided in each wheel 12 and detects the amount of rotation of each wheel 12 and the number of rotations per unit time, and outputs the number of wheel speed pulses indicating the detected number of rotations as a detection value. The wheel speed sensor 40 can be configured using, for example, a hall element. The ECU 24 calculates the vehicle speed, the amount of movement, and the like of the vehicle 10 based on the detection value acquired from the wheel speed sensor 40, and executes various controls. When the ECU 24 calculates the vehicle speed of the vehicle 10 based on the detection value of the wheel speed sensor 40 of each wheel 12, the ECU 24 determines the vehicle speed of the vehicle 10 based on the speed of the wheel 12 having the smallest detection value among the four wheels. Execute control. In addition, when there is a wheel 12 having a detected value larger than that of the other wheels 12 among the four wheels, the ECU 24 has a rotation speed in a unit period (unit time or unit distance) as compared to the other wheels 12, for example. When there are more than a predetermined number of wheels 12, the wheels 12 are considered to be in a slip state (idling state), and various controls are executed. The wheel speed sensor 40 may be provided in the brake system 32. In that case, the ECU 24 acquires the detection result of the wheel speed sensor 40 via the brake system 32.

  The configuration, arrangement, electrical connection form, and the like of the various sensors and actuators described above are examples, and can be set (changed) in various ways.

  For example, the ECU 24 performs a parking support process based on the captured image data acquired from the imaging unit 14, or transmits data related to the peripheral image and sound generated based on the captured image data to the monitor device 22.

  CPU24a is provided with various modules as shown in Drawing 6 mentioned below, for example, for example, performs processing related to parking support. For example, the CPU 24a performs arithmetic processing, image processing, and the like on the captured image data captured by the imaging unit 14 to search for (present) a parking area candidate in which the vehicle 10 can be parked, or to set the vehicle 10 in the parking area. The parking target position to be guided is set, the current position of the vehicle 10 is estimated, or the vehicle 10 is guided to the parking target position. Details of the CPU 24a will be described later.

  In the present embodiment, the ECU 24 parks the vehicle 10 in the parking area automatically or semi-automatically while reducing the burden on the driver by cooperation of hardware and software (control program). As a parking support mode, the parking support system 100 executes a steering operation, an acceleration / deceleration operation, a braking operation, and the like for guiding the vehicle 10 to the movement target position set in the parking area, and the driver starts the support. There is “full automatic parking assistance” that does not require any operation other than the above. In addition, “semi-automatic parking assistance” in which at least one operation of full automatic parking assistance is entrusted to the driver or the operation content of the vehicle 10 is provided to the driver by voice or display, and the driver operates the vehicle 10 according to the operation content. There is "guidance support" to run. In the following description, “full automatic parking assistance” in which the vehicle 10 enters the parking area while moving backward is described as an example.

  First, the outline of parking assistance will be described with reference to FIG. FIG. 3 is a diagram illustrating an example of parking assistance of the vehicle 10 by the parking assistance system 100 (parking assistance device), and conceptually explains the search of the parking area 42 and the guidance of the vehicle 10 by the movement route L1. It is a bird's-eye view schematic diagram. In FIG. 3, for example, a plurality of parking areas 42 defined by a pair of dividing lines 44a and dividing lines 44b (hereinafter referred to as dividing lines 44 when not distinguished) are aligned (for example, parking areas 42A to 42F are arranged side by side). This is an example in which the vehicle 10 enters the parking lot P that is aligned) for parking. The lane markings 44a and 44b are, for example, white lines painted on the parking road surface so as to define a parking area 42 having a sufficient width W and a depth D that allows parking of a general passenger car (for example, the vehicle 10). Be placed. The parking assistance system 100 searches for a parking area 42 that can be parked when the vehicle 10 travels at a parking area search speed or less (for example, 30 km / h or less). In the case of FIG. 3, the parking assist system 100 has an imaging unit 14c mounted on the vehicle 10 while traveling in the parking lot traveling space PS in which the parking areas 42 are lined up in the parking lot P (for example, traveling along the traveling locus L2). The imaging unit 14d searches for a parking area 42 (only one of the parking areas 42 is shown in FIG. 3) that may exist around the vehicle 10 (for example, left and right). The parking support system 100 sequentially performs image processing such as edge processing on an image captured while traveling, and also executes, for example, straight line detection and the like, and the lane markings 44a and 44b and the lane markings 44 and the like. Recognize something similar. When a pair of lane markings 44a and 44b adjacent to each other at an interval wider than the vehicle width of the vehicle 10 are recognized, an area defined by the pair of lane markings 44a and 44b is defined as a parking area 42. recognize. Furthermore, when there is no object such as another vehicle in the recognized parking area 42, the parking support system 100 registers the parking area 42 as a candidate for the parking area 42 that can be parked and, for example, in the display device 16. Display and present to the driver.

  When the driver selects a parking area 42 that he wants to park from the proposed parking areas 42, the parking support system 100 moves to guide and store the vehicle 10 in the selected parking area 42. A target position T1 is set. The parking support system 100, for example, in addition to the vehicle width and length of the vehicle 10, in addition to the position of the tip of the lane lines 44a and 44b constituting the selected parking area 42 and the lane line 44a obtained as a result of straight line detection. The movement target position T1 is set based on the direction (angle) in which the partition line 44b extends. The movement target position T1 is, for example, a reference position set at the center position in the vehicle width direction of the rear wheel shaft 12a that supports the rear wheel 12R of the vehicle 10 when the vehicle 10 is within the selected parking area 42. The position where T2 exists is set. Therefore, the parking assistance system 100 calculates the movement route L1 connecting the reference position T2 indicating the current position of the vehicle 10 and the movement target position T1 using a known technique, and follows the movement route L1 along the movement route L1. The vehicle 10 can be parked in the selected parking area 42 by guiding the vehicle backward.

  As described above, when searching for the parking area 42, the parking support system 100 recognizes the lane marking 44 with a relatively high vehicle speed. Therefore, the recognition accuracy of the lane marking 44a and the lane marking 44b may be lowered. And the movement target position T1 set at the start stage of parking assistance performs straight line detection on the lane line 44a and the lane line 44b that are recognized in a relatively fast vehicle speed. It is determined by estimating the position (tilt). Thus, when the lane markings 44a and 44b with low recognition accuracy are used, the setting accuracy of the movement target position T1 and the movement route L1 may not be high accuracy, and the vehicle 10 is positioned at a predetermined position in the parking area 42. In some cases, it is not possible to guide to the center position (for example, the center position without left-right bias). Therefore, the parking assist system 100 according to the present embodiment recognizes the lane line 44 and calculates using the recognized lane line 44 while the vehicle 10 is guided according to the movement route L1 and gradually approaches the parking area 42. Are repeatedly executed, for example, the position correction of the movement target position T1 and the reference position T2 indicating the current position of the vehicle 10 is executed, and the movement route L1 is further corrected.

  For example, when the guided traveling of the vehicle 10 is started based on the movement route L1 set when the parking area 42 is selected, the parking support system 100 monitors the movement state of the vehicle 10 with respect to the movement target position T1 and the movement target position T1. In order to perform the position correction and the like, the surroundings are photographed by the imaging unit 14a installed at the rear of the vehicle 10. And the parking assistance system 100 starts re-recognition of the lane marking 44 based on a back image. However, each imaging unit 14 mounted on the vehicle 10 including the rear imaging unit 14a uses a wide-angle lens or a fish-eye lens so as to enable a wide range of imaging. As a result, as shown in FIG. 4, the captured image 46 is an entirely curved image (an image corresponding to the reflected rear bumper 10 a, the horizon, the partition line 44, etc.). In this case, an object (for example, a lane marking 44a or a lane marking 44b) recognized in the image 46 appears smaller as it is farther from the imaging unit 14a. When edge processing or straight line detection is performed on a small division line 44, it is difficult to expect high detection accuracy such as the position of the edge of the division line 44 and the direction (angle) of the division line 44. In addition, depending on the relative relationship between the vehicle 10 and the lane marking 44, the recognition accuracy may be different between the lane marking 44 reflected in the vicinity and the lane marking 44 reflected in the distance. As a result, the parking assistance system 100 recognizes the shape different from the actual state, for example, the parking area 42 in a curved state, or erroneously recognizes the extending direction of the parking area 42 (partition line 44). Sometimes In this case, the parking assistance system 100 may misrecognize the width and position of the parking area 42, and may improperly correct the movement target position T1, the reference position T2, and further the movement route L1. is there.

  Therefore, the parking assist system 100 according to the present embodiment can ensure higher recognition accuracy when it is determined that there is a difference in recognition accuracy with respect to the pair of lane markings 44 that define the selected parking area 42. The lane marking 44 is used to recognize and correct the movement target position T1 and the current position of the vehicle 10 (reference position T2), and further to correct the movement path L1. As an example, as shown in FIG. 5, consider a situation where the vehicle 10 faces the rear of the vehicle to the parking area 42 and is about to enter the parking area 42 by traveling backward. In such a situation, the first direction X extending through the currently set movement target position T1 and extending in the length direction of the selected parking area 42 (the extending direction of the partition line 44), and the vehicle 10 A first angle θ that is an acute angle among the angles formed with the second direction Y extending along the front-rear direction and passing through the reference position T2, for example, is detected. Then, by comparing the first angle θ with the second angle φ, which is an acute angle set in advance with respect to the first direction X, the attitude of the vehicle 10 with respect to the lane marking 44 (with the vehicle 10 and The difference in relative distance between the lane marking 44a and the lane marking 44b) is detected.

  For example, when the first angle θ is larger than the second angle φ as a result of the comparison, the distance from the vehicle 10 (imaging unit 14a) to the pair of lane markings 44 (the lane marking 44a and the lane marking 44b). Is different. As a result, the lane marking 44 (for example, the lane marking 44b) far from the vehicle 10 has a lower recognition accuracy than the near lane marking 44 (for example, the lane marking 44a), and an error occurs when edge detection or straight line recognition is performed. It is considered that the recognition rate exceeds the allowable range and is not suitable for correcting the movement target position T1. In this case, of the pair of lane markings 44 (the lane marking 44a and the lane marking 44b), the lane marking 44 (for example, the lane marking 44a) closer to the vehicle 10 is used for correction control of the movement target position T1 and the reference position T2. Recognized as a line 44.

  On the other hand, when the first angle θ is equal to or smaller than the second angle φ, the second direction Y is approaching the first direction X. That is, the difference between the relative distance from the vehicle 10 (imaging unit 14a) to the lane marking 44a and the relative distance from the vehicle 10 (imaging unit 14a) to the lane marking 44b is reduced, and the lane marking 44a and the lane marking 44b on the image 46 are reduced. Can be seen in the same way. Therefore, the difference in recognition accuracy when edge detection or straight line recognition is applied to the lane marking 44a and the lane marking 44b is small, and the recognition accuracy of the width and shape of the parking area 42 defined by the lane marking 44a and the lane marking 44b is reduced. It can be regarded as not worsening. In this case, the recognition accuracy of the width and posture (angle) of the parking area 42 can be improved by recognizing the parking area 42 from the dividing line 44a and the dividing line 44b having a small recognition accuracy difference. Therefore, the movement target position T1 is corrected and set to an accurate position from the movement target position T1 set by the lane marking 44 recognized when passing through the parking lot traveling space PS (see FIG. 3) in the parking lot P. Can do. Therefore, when the first angle θ is equal to or smaller than the second angle φ, the parking support system 100 recognizes both the pair of lane lines 44a and 44b as the lane lines 44 used for correction control of the movement target position T1. To do.

  For example, when the first angle θ is larger than the second angle φ, the lane marking 44 a is recognized in the search range 48 a near the vehicle 10. In this case, since the search range is limited to the vicinity side, it can contribute to the reduction of the image processing load in the parking support system 100. When the first angle θ is equal to or smaller than the second angle φ, the lane marking 44a is recognized in the search range 48a near the vehicle 10 and the lane marking 44b is detected in the search range 48b far away from the vehicle 10. Recognize. In this case, as described above, the parking area 42 can be recognized by the pair of division lines 44a and the division lines 44b, and the recognition accuracy of the width and posture (angle) of the parking area 42 can be improved. That is, the correction accuracy of the movement target position T1 can be improved. When the relative distance between the parking area 42 and the vehicle 10 is long and the first angle θ is equal to or less than the second angle φ, the recognition accuracy of the lane marking 44a and the lane marking 44b may be low. However, the recognition accuracy difference between the lane marking 44a and the lane marking 44b is small, and the width and shape of the parking area 42 defined by the lane marking 44a and the lane marking 44b can be recognized. In this case, since the vehicle 10 approaches the parking area 42 without making a large turn, the recognition accuracy is gradually improved while the difference in recognition accuracy between the lane marking 44a and the lane marking 44b is small. Therefore, the movement target position T1 can be corrected by using the lane marking 44a and the lane marking 44b.

  The first direction X is defined as a straight line that passes through the movement target position T1 and extends in the length direction of the selected parking area 42. For example, the first direction X is recognized when the vehicle 10 searches the parking area 42. The accuracy of the lane marking 44 may be low as described above. Therefore, the accuracy of the first direction X defined in the length direction of the parking area 42 may be low. Therefore, the parking assistance system 100 approaches the parking area 42 and uses the recognized lane marking 44 in the first direction X every time the recognition accuracy of the lane marking 44 (the lane marking 44a or the lane marking 44b) is improved. May be corrected. In addition, the second angle φ varies depending on the performance of the imaging unit 14, the mounting position in the vehicle 10, and the like, but it can be determined in advance by evaluating the recognition accuracy of the lane marking 44 due to the difference in the first angle θ by a test or the like. it can. The second angle φ can be “30 °”, for example, but can be changed as appropriate.

  FIG. 6 is an exemplary block diagram of the configuration of the CPU 24a included in the ECU 24 (see FIG. 2) that realizes the recognition process of the lane marking 44 and the correction process of the movement path L1 as described above. The CPU 24a includes various modules for executing the parking support process as described above. The various modules are realized by the CPU 24a reading a program installed and stored in a storage device such as the ROM 24b and executing it. For example, as illustrated in FIG. 6, the CPU 24 a, as shown in FIG. 6, the image acquisition unit 50, the projection conversion unit 52, the vehicle position acquisition unit 54, the recognition unit 56, the setting unit 58, the route acquisition unit 60, the trigger acquisition unit 62, guidance control. Modules such as a unit 64, a comparison unit 66, and a correction unit 68 are provided. Note that each module shown in FIG. 6 is illustrated for each function, and the module may be changed as appropriate, and the same effect can be obtained even if the functions described below are integrated or separated. it can.

  The image acquisition unit 50 acquires the image captured by the imaging unit 14 via the display control unit 24d. In the case of this embodiment, when searching for the parking area 42, when acquiring the side image of the vehicle 10 imaged mainly by the imaging units 14c and 14d and receiving parking assistance at the time of warehousing by reverse running, A rear image of the vehicle 10 captured mainly by the imaging unit 14a is acquired. In another embodiment, when parking assistance is received at the time of warehousing by forward traveling, a front image of the vehicle 10 captured mainly by the imaging unit 14b is acquired. The image acquisition unit 50 provides the acquired image to the projection conversion unit 52. Note that the display control unit 24d displays the image captured by the image capturing unit 14 by performing image processing such as distortion correction, displays the image without performing image processing, or displays it superimposed on other data. The processing may be performed by the display control unit 24d and displayed on the display device 16.

  The projection conversion unit 52 performs, for example, a well-known projection conversion process on the peripheral image of the vehicle 10 acquired by the image acquisition unit 50 so that the parking area 42 as shown in FIG. 3 or FIG. Convert to a 3D image.

  The vehicle position acquisition unit 54 acquires the current position (vehicle position) of the vehicle 10 on the coordinate system defined by the three-dimensional image converted by the projection conversion unit 52. For example, as a vehicle design value of the vehicle 10, the relationship between the mounting position of the imaging unit 14a and the center position of the rear wheel shaft 12a in the vehicle width direction is known. Therefore, when the projection conversion unit 52 performs projection conversion of the image captured by the imaging unit 14a, the position of the reference position T2 can be determined on the three-dimensional coordinates. Similarly, the relationship between the mounting position of the imaging unit 14c and the imaging unit 14d and the center position of the rear wheel shaft 12a in the vehicle width direction is known. Accordingly, the vehicle position acquisition unit 54 determines the current position of the vehicle 10 with respect to a reference point (for example, the origin) determined on the projection-transformed three-dimensional coordinates acquired when searching for the parking area 42 or after parking assistance is started. The position can be acquired sequentially.

  The recognition unit 56 performs, for example, edge processing on the projection-converted image and performs straight line detection processing to recognize the partition line 44. As described above, when the parking area 42 is searched, the recognition accuracy of the lane marking 44 by the recognition unit 56 is not so high. On the other hand, by executing the parking support, the recognition result of the lane line 44 is sequentially updated while the vehicle approaches the selected parking area 42, and the recognition accuracy of the lane line 44 by the recognition unit 56 is improved. In addition, the recognition unit 56 searches for a region having a frontage that can be used as the parking region 42 by calculating a relative distance (separation distance) between the adjacent division lines 44 with respect to the recognized division line 44. . The recognizing unit 56 recognizes the pair of lane lines 44 (the lane line 44a and the lane line 44) when a pair of lane lines 44 adjacent to each other at an interval wider than the vehicle width of the vehicle 10 is recognized based on the recognition result of the lane line 44. 44b) is defined as a parking area 42. Furthermore, the recognition part 56 registers the parking area 42 as a candidate of the parking area 42 which can be parked, when objects (obstacles), such as another vehicle, do not exist in the detected parking area 42. FIG. And the recognition part 56 displays the information of the registered parking area 42 on the display apparatus 16 via the display control part 24d, and shows it to a driver | operator. When displaying the candidate of the parking area 42, the display control unit 24d may display a message that causes the driver to select one of the candidates. When the vehicle 10 includes a distance measuring unit such as a sonar, the recognition unit 56 detects an object (obstacle) in the parking area 42 based on the distance measurement result and can use the available parking area 42. The candidates may be determined.

  The setting unit 58 sets the movement target position T1 in the selected parking area 42 based on the pair of lane lines 44a and 44b that define the parking area 42 selected by the driver. The movement target position T1 is a position at which the reference position T2 when the vehicle 10 enters the parking area 42 is guided. The position in the width direction of the parking area 42 of the movement target position T1 is, for example, the midpoint position in the separation direction of the pair of lane markings 44a and 44b detected in a straight line. Further, the position in the depth direction of the parking area 42 of the movement target position T1 is, for example, from the front end portion 44c on the entrance side of the recognized lane marking 44 to the reference position T2 from the front end of the vehicle 10 (front bumper 10b). The position can correspond to the distance. The setting unit 58 may automatically select the parking area 42 that satisfies a preset condition from the candidates for the parking area 42 presented by the recognition unit 56 and set the movement target position T1. Good.

  The route acquisition unit 60 is a well-known recommended travel route calculation technique based on the movement target position T1 set based on the lane line 44 currently recognized by the setting unit 58 and the reference position T2 at the current position of the vehicle 10. Is used to calculate the travel route L1.

  The trigger acquisition unit 62 acquires a trigger signal for starting parking support processing in the parking support system 100. For example, when the vehicle 10 is parked while traveling backward, as a parking assistance preparation process, searching for candidates for the parking area 42, selection of the parking area 42 for which parking is desired, and setting of the movement target position T1 (for example, initial setting) The detection (for example, initial estimation) of the reference position T2 is performed. And when actually starting parking assistance, a driver moves a gear shift operation part (for example, shift lever) to "R position". In the case of the parking assistance system 100, as an example, the movement of the speed change operation unit based on the detection result of the shift sensor 38 to the “R position” is set as a parking assistance start trigger. In another embodiment, parking assistance may be started by input by the operation input unit 20 or voice input, and the trigger acquisition unit 62 may acquire those input signals.

  The guidance control unit 64 performs guidance processing based on the movement target position T1 and the reference position T2 that is the current position of the vehicle 10, that is, guidance processing so that the vehicle 10 is moved along the movement route L1 acquired by the route acquisition unit 60. Execute. When executing “fully automatic parking assistance”, the guidance control unit 64 controls the steering system 28, the brake system 32, the drive system 34, and the like to cause the vehicle 10 to travel backward along the movement path L1 and to perform the reference. The position T2 is moved closer to the movement target position T1. In the case of “semi-automatic parking assistance” and “guidance assistance”, the parking operation is performed by providing the driver with the operation content by voice or display and the driver executing part or all of the operation.

  As described with reference to FIG. 5, the comparison unit 66 passes through the movement target position T <b> 1 in the first direction X extending in the length direction of the parking area 42 (extending direction of the partition line 44), and in the longitudinal direction of the vehicle 10. A first angle θ formed along the second direction Y extending along the reference position T2 is compared with a preset second angle φ. As described above, each time the recognizing unit 56 re-recognizes the lane marking 44, straight line detection of the lane marking 44 is executed, so that the position of the movement target position T1 and the direction of the first direction X are updated. Similarly, since the current position (reference position T2) of the vehicle 10 changes as the vehicle 10 moves, the second direction Y is updated. Therefore, for example, the comparison unit 66 can compare the first angle θ and the second angle φ in the recognition cycle of the lane markings 44 by the recognition unit 56. The comparison unit 66 provides the comparison result to the correction unit 68. The comparison unit 66 may execute the comparison process only when the distance from the movement target position T1 to the vehicle 10 (distance to the reference position T2) is equal to or less than a predetermined value (division line recognition start distance). Good. For example, when the distance from the movement target position T1 to the vehicle 10 (the distance to the reference position T2) exceeds a predetermined value (for example, 6 m), the recognition accuracy is expected to be improved even on the lane marking 44 on the side close to the vehicle 10. It is determined that it cannot be performed, and recognition of the lane marking 44 for resetting the movement target position T1 is temporarily stopped. In this case, since the reset of the movement target position T1 is not performed, the route acquisition unit 60 does not reset the movement route L1. In this case, since the position of the vehicle 10 is far from the movement target position T1, accurate guidance is not necessarily required, and there is no problem even if the movement route L1 based on the movement target position T1 set at the time of searching is used as it is. Can be considered. Thus, by adding control based on the lane marking recognition start distance, when the position of the vehicle 10 is far from the movement target position T1, the accuracy of the currently set movement target position T1 and movement path L1 is deteriorated. It is possible to prevent such correction. Moreover, it can contribute to reduction of the processing load of the parking assistance system 100. And the guidance control part 64 guides the vehicle 10 using the movement route L1 based on the movement target position T1 set at the time of search as it is, and the distance from the movement target position T1 to a vehicle becomes below predetermined value. Like that. Thereafter, the comparison unit 66 executes the comparison process only when the distance from the movement target position T1 to the vehicle 10 is equal to or less than a predetermined value, and determines which lane marking 44 is to be recognized.

  Based on the comparison result of the comparison unit 66, the correction unit 68 causes the recognition unit 56 to perform re-recognition of the lane marking 44, and based on the result of the re-recognition, the setting unit 58 corrects the movement target position T1. Execute (Setting). Specifically, when the correction unit 68 obtains a result indicating that the first angle θ is larger than the second angle φ as the comparison result of the comparison unit 66, the correction unit 68 sets the vehicle 10 out of the pair of lane markings 44. It is determined that edge processing and straight line detection can be performed with a higher accuracy on the closer lane marking 44 (in the case of FIG. 5, the lane marking 44a in FIG. 5) with higher accuracy than the far lane marking 44 (in the case of FIG. 5 lane marking 44b). . Therefore, the correction unit 68 causes the recognition unit 56 to perform re-recognition of the lane marking 44 (the lane marking 44a) in the search range 48a. As a result, for example, the setting unit 58 can reset the movement target position T1 based on the lane marking 44a closer to the vehicle 10, which is likely to be recognized more accurately. For example, the setting unit 58 offsets the position in the width direction of the movement target position T1 in the parking area 42 by a predetermined amount offset from the recognized marking line 44a by a distance of ½ the vehicle width of the vehicle 10 in the parking area 42 inward. It is determined by the added value of the distance. In this case, the distance offset by a predetermined amount is the distance between the right end of the vehicle 10 and the lane marking 44a when the vehicle 10 is parked in the parking area 42, and can be set to 150 mm, for example. In addition, about the 1st direction X, the parallelism with respect to the division line 44 can be improved by resetting based on the division line 44a nearer to the vehicle 10 with a high possibility of being recognized more correctly. . As a result, the comparison accuracy when comparing the first angle θ and the second angle φ in the next control cycle can be improved.

  On the other hand, when the correction unit 68 obtains a result indicating that the first angle θ is equal to or smaller than the second angle φ as the comparison result of the comparison unit 66, both of the pair of lane lines 44 (the lane lines 44a and 44) The partition line 44b) determines that edge processing and straight line detection can be performed with higher accuracy. That is, the difference in relative distance from the vehicle 10 (for example, the reference position T2) to the lane marking 44a and the lane marking 44b is small. That is, the difference in recognition accuracy between the lane marking 44a and the lane marking 44b is small, and it is determined that edge processing and straight line detection can be performed with the same accuracy. Then, the correction unit 68 causes the recognition unit 56 to perform re-recognition of the division line 44 (partition line 44a) in the search range 48a, and re-recognition of the division line 44 (partition line 44b) in the search range 48b. Run recognition. As a result, the setting unit 58 can reset the movement target position T1 based on the lane markings 44a and 44b that can ensure the same level of recognition accuracy. In this case, the setting accuracy of the center position in the width direction of the parking area 42 of the movement target position T1 can be improved as compared with the case where the movement target position T1 is set only by one lane marking 44. It should be noted that the first direction X is also set in parallel with the lane lines 44 by setting again based on the pair of lane lines 44a and 44b, as compared with the case where the lane line 44 is set with only one lane line 44 (lane line 44a). The degree can be improved. As a result, the comparison accuracy when comparing the first angle θ and the second angle φ in the next control cycle can be improved.

  Furthermore, the correction unit 68 corrects (resets) the movement route L1 based on the movement target position T1 set by the lane marking 44 newly recognized by the route acquisition unit 60 according to the comparison result of the comparison unit 66. Is executed. For example, when the first angle θ is larger than the second angle φ, the correction unit 68 sets the movement target position T1 and the vehicle position that are set again by the setting unit 58 using the lane marking 44a in the route acquisition unit 60. Using the current position (reference position T2) of the vehicle 10 acquired by the acquisition unit 54, the movement route L1 is corrected (reset). In this case, it is possible to set the movement target position T1 whose positional accuracy is improved with respect to the actual lane line 44 (division line 44a) from the initially set movement target position T1 when the vehicle 10 searches the parking area 42. Thus, the accuracy of the movement route L1 set based on the movement target position T1 can be improved. Similarly, when the first angle θ is equal to or smaller than the second angle φ, the correction unit 68 moves the movement target position reset by the setting unit 58 to the route acquisition unit 60 using the division lines 44a and 44b. By using T1 and the current position (reference position T2) of the vehicle 10 acquired by the vehicle position acquisition unit 54, correction (resetting) of the movement route L1 is executed. In this case, the positional accuracy of the actual lane line 44 is higher than the movement target position T1 that is initially set when the vehicle 10 searches the parking area 42 or the movement target position T1 that is reset only using the lane line 44a. The improved movement target position T1 can be set. Therefore, it is possible to further improve the accuracy of the movement route L1 set based on the movement target position T1. Therefore, the vehicle 10 can be parked at a more ideal position within the parking area 42, that is, at a position where an appropriate gap is secured on the front, rear, left and right of the vehicle 10 in the parking area 42.

  The parking support process by the parking support system 100 configured as described above will be described with reference to the flowchart of FIG.

  First, the imaging unit 14 of the vehicle 10 normally captures a peripheral image of the vehicle 10 at all times. However, for example, when the vehicle is traveling at a speed of 30 km / h (parking area search speed) or less, the parking support system 100 operates as a driver. Considers driving while finding a parking space. And the parking assistance system 100 acquires the surrounding image of the vehicle 10 by the imaging part 14c and the imaging part 14d, for example, in order to search the parking area 42 as a preparation stage for parking assistance (S100).

  The projection conversion unit 52 sequentially performs projection conversion processing on an image captured while traveling, and the recognition unit 56 performs edge processing, straight line detection processing, obstacle detection processing, and the like on the projection-converted image, A candidate for the parking area 42 is searched, and the search result is displayed (presented) on the display device 16 (S102). When the specific parking area 42 is not selected from the presented candidates for the parking area 42 by the driver or the setting unit 58 (No in S104), the process returns to S100 and the parking area 42 based on the newly acquired image is displayed. Repeat the candidate presentation.

  On the other hand, when the parking area 42 is selected by the driver or the setting unit 58 (Yes in S104), the setting unit 58 acquires a temporary (initial) movement target position T1 (S106). In addition, the host vehicle position acquisition unit 54 acquires a reference position T2 that can be regarded as the position of the vehicle 10 (current host vehicle position) when the movement target position T1 is temporarily set (S108). Subsequently, the route acquisition unit 60 acquires the movement route L1 based on the temporarily set movement target position T1 and the reference position T2 (S110).

  And the trigger acquisition part 62 confirms whether the trigger signal for starting a parking assistance process was received (it acquired) (S112). When the trigger acquisition unit 62 has not received a trigger signal (No in S112), the process returns to S108. As a result, the own vehicle position acquisition unit 54 re-acquires the current position (reference position T2) of the vehicle 10, and the route acquisition unit 60 acquires the updated current position (reference position T2) of the vehicle 10 and S106. A new movement path L1 is acquired based on the moving target position T1.

  In S112, when the trigger acquisition unit 62 receives the trigger signal (Yes in S112), the recognition unit 56 determines that the distance from the movement target position T1 to the vehicle 10 (distance to the reference position T2) is a predetermined value (division line). It is confirmed whether it is less than (recognition start distance) (S114). When the distance is equal to or less than the lane marking recognition start distance (for example, 6 m), the comparison unit 66 compares the first angle θ with the second angle φ (S116). In S116, when the first angle θ> the second angle φ (Yes in S116), the recognition unit 56 recognizes the division line 44 (division line 44a) closer to the vehicle 10 (near side) (division line 44a). S118). On the other hand, when the first angle θ> the second angle φ is not satisfied (No in S116), that is, when the first angle θ ≦ the second angle φ, the recognizing unit 56 determines the dividing lines 44 (partitions 44) on both sides. The line 44a and the partition line 44b) are recognized (S120).

  Then, the correction unit 68 causes the setting unit 58 to execute correction (reset) of the movement target position T1 based on the recognized marking line 44 (S122). Further, the correction unit 68 sends the movement route to the route acquisition unit 60 based on the movement target position T1 reset by the setting unit 58 by the lane marking 44 newly recognized by the recognition unit 56 as a result of the comparison by the comparison unit 66. Correction (re-setting) of L1 is executed (S124).

  The guidance control unit 64 performs guidance of the vehicle 10 based on the corrected (reset) travel route L1 (S126), and the position of the reference position T2 (own vehicle position) acquired by the own vehicle position acquisition unit 54. Does not reach the movement target position T1 (No in S128), the process returns to S114, and the subsequent processes are repeated. Further, when the position (vehicle position) of the reference position T2 acquired by the vehicle position acquisition unit 54 has reached (can be regarded as) the movement target position T1 (Yes in S128), the guidance control unit 64 performs a series of parking operations. Complete the support process. In this case, the guidance control unit 64 may display a parking support completion message or the like on the display device 16 or the like.

  In the process of S114, when the recognition unit 56 determines that the distance from the movement target position T1 to the vehicle (distance to the reference position T2) is not less than the lane marking recognition start distance (No in S114). By skipping the processing of S116 to S124, the guidance control unit 64 performs guidance of the vehicle 10 based on the currently set movement route L1, and determines whether the reference position T2 has reached the movement target position T1. (S128) If not reached, the processing from S114 is executed.

  As described above, when the first angle θ is larger than the second angle φ, the movement target position T1 and the movement route L1 can be reset using the lane marking 44 that can improve the recognition accuracy in the vicinity of the vehicle 10. . As a result, it is possible to realize guidance of the vehicle 10 by the movement route L1 in which additional guidance control such as turning back is difficult to occur. In addition, when the first angle θ is equal to or smaller than the second angle φ, the movement target position T1 and the movement using both of the lane markings 44 (the lane marking 44a and the lane marking 44b) that can be recognized with a small difference in accuracy. The route L1 can be reset. As a result, the position accuracy with respect to the actual lane line 44 is determined from the movement target position T1 temporarily set when the vehicle 10 searches the parking area 42 or the movement target position T1 reset only using the lane line 44a. The improved movement target position T1 can be set. Therefore, it is possible to further improve the accuracy of the movement route L1 set based on the movement target position T1. That is, the vehicle 10 can be guided and parked at a more ideal position in the parking area 42. That is, in the parking area 42, it is possible to prevent the vehicle 10 from being guided toward one of the lane markings 44 or guided in a tilted position within the parking area 42, and the vehicle 10 can be prevented from being parked. In this way, it is possible to realize parking at a more appropriate position while ensuring an appropriate gap on the front, rear, left and right sides of the vehicle body.

  In the parking support process described in the flowchart of FIG. 7, the correction unit 68 determines the lane line 44 recognized based on the comparison between the first angle θ and the second angle φ, and moves based on the recognized lane line 44. An example is shown in which the movement route L1 is reset after correcting (resetting) the target position T1. In this case, as the accuracy of the movement target position T1 is improved, the setting accuracy of the movement route L1 based on the movement target position T1 is improved, and the guidance accuracy of the vehicle 10 is improved. In another embodiment, the correction unit 68 determines the lane line 44 to be recognized based on the comparison between the first angle θ and the second angle φ, and the vehicle position of the vehicle 10 based on the recognized lane line 44. The movement path L1 may be reset by redetecting (current position, reference position T2). In the case of the above-described example, the current position (reference position T2) of the vehicle 10 is not related to the recognition of the lane marking 44, but using the detection signals from the wheel speed sensor 40, the steering angle sensor 30, etc. An error occurs when the position changes due to vibration or the like. On the other hand, by detecting the lane marking 44 based on the image captured by the imaging unit 14 and detecting the current position of the vehicle 10 (reference position T2) based on the recognition result, the detection accuracy of the current position of the vehicle 10 is improved. Maintenance improvement is possible. As the accuracy of the reference position T2 with respect to the lane marking 44 is improved, the setting accuracy of the movement route L1 based on the reference position T2 can be improved, and the guidance accuracy of the vehicle 10 can be improved. .

  In this case, when the lane marking 44 is recognized according to the comparison result of S116 (S118, S120), instead of the processing of S122, refer to, for example, the tip 44c (see FIG. 5) of the recognized lane marking 44, The current position (reference position T2) of the vehicle 10 may be detected. In this case, the correction unit 68 can cause the host vehicle position acquisition unit 54 to detect the current position of the vehicle 10 based on the lane marking 44 with high recognition accuracy in the image acquired by the image acquisition unit 50. . Then, the correction unit 68 causes the route acquisition unit 60 to correct (reset) the movement route L1 determined using the movement target position T1 and the current position of the vehicle 10 (reference position T2) (S124). And the guidance control part 64 implements guidance control of the vehicle 10 (S126). As a result, similarly to the case of the movement route L1 that is reset using the corrected movement target position T1, the setting accuracy of the movement route L1 is improved, and the guidance accuracy of the vehicle 10 can be improved. In the case where the current position of the vehicle 10 is detected, both the lane markings 44 (the lane marking 44a and the lane marking 44b) are used rather than the case where only the lane marking 44 (the lane marking 44a) near the vehicle 10 is used. However, since the detection accuracy is improved, it is possible to set the movement path L1 closer to the ideal.

  In another embodiment, both the correction of the movement target position T1 and the detection (correction) of the reference position T2 may be performed based on the recognized lane marking 44, and the movement based on the lane marking 44 with high recognition accuracy. The movement route L1 may be reset by the target position T1 and the reference position T2. In this case, it is possible to further improve the setting accuracy of the movement route L1, and the vehicle 10 is guided toward one of the lane markings 44 or guided in a tilted posture within the parking area 42. Is more suppressed.

  In the embodiment described above, the example in which the guidance control unit 64 guides the vehicle 10 to the movement target position T1 based on the movement route L1 acquired (set, reset) by the route acquisition unit 60 has been described. In another embodiment, the guidance control unit 64 is an index indicating the parking area 42 to be guided from now on based on the movement target position T1 and the current position (reference position T2) of the vehicle 10 as an example of guidance processing of the vehicle 10. May be displayed on the display device 16. As an index indicating the parking area 42, a “parking frame” that is displayed so as to overlap with the partition line 44 (44 a, 44 b) of the parking area 42 to be guided or displayed inside the partition line 44 (44 a, 44 b). It can be. The “parking frame” may be a rectangular frame that is entirely enclosed by a diagram, etc., may be a frame that shows only portions corresponding to the four corners of the parking frame, or a frame that displays only side portions other than the four corners. But you can. In this case, since the recognition accuracy of the relative positional relationship between the parking area 42 and the vehicle 10 is improved based on the movement target position T1 and the reference position T2 whose accuracy has been improved based on the lane marking 44 re-recognized by the recognition unit 56, An indicator (for example, a parking frame) indicating the parking area 42 can be displayed on the display device 16 at a more accurate position with respect to the vehicle 10. As a result, when the vehicle 10 is guided, it is easy for the driver to grasp a more accurate parking position and to give a higher sense of security. The “parking frame” is an example of an “index”, and can be appropriately changed as long as it indicates information regarding the position of the parking area 42 to be guided from now on, and may be a mark other than a diagram.

  Moreover, in embodiment mentioned above, the parking assistance at the time of the reverse parking which the vehicle 10 enters into the parking area | region 42, traveling backwards was demonstrated. In another embodiment, during forward parking when the vehicle 10 travels forward and enters the parking area 42, the lane marking 44 is similarly recognized, and at least one of correction of the movement target position T1 and detection of the reference position T2 is performed. And parking assistance may be performed while resetting the movement route L1, and the same effect can be obtained.

  In the embodiment described above, the example in which the CPU 24a calculates or guides the vehicle position of the vehicle 10, the movement route L1, the content of the guidance control executed by the guidance control unit 64, and the like has been shown. In another embodiment, for example, various types of information are transmitted to an external center, the center side calculates the vehicle position and movement route L1 of the vehicle 10, and determines the guidance content of the vehicle 10 to determine the vehicle 10 , The vehicle 10 may be controlled, and the same effect can be obtained.

  In the above-described embodiment, the lane marking 44 has been illustrated as being painted on the parking road surface, but is not limited thereto, and may be any lane marking that can be recognized by performing image processing on the captured image. For example, the present embodiment can be applied to the case where the dividing line is formed by a rope or the like, and the same effect can be obtained.

  A program for parking support processing executed by the CPU 24a of the present embodiment is a file in an installable or executable format, and is a CD-ROM, flexible disk (FD), CD-R, DVD (Digital Versatile Disk). For example, the program may be recorded on a computer-readable recording medium.

  Furthermore, the parking assistance processing program may be stored on a computer connected to a network such as the Internet and provided by being downloaded via the network. Moreover, you may comprise so that the parking assistance processing program performed by this embodiment may be provided or distributed via networks, such as the internet.

  Although embodiments and modifications of the present invention have been described, these embodiments and modifications are presented as examples and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the scope of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalents thereof.

  DESCRIPTION OF SYMBOLS 10 ... Vehicle, 12a ... Rear-wheel axle, 14, 14a, 14b, 14c, 14d ... Imaging part, 16 ... Display apparatus, 24 ... ECU, 24a ... CPU, 42 ... Parking area, 44, 44a, 44b ... Dividing line, 44c ... tip part, 46 ... image, 48a, 48b ... search range, 50 ... image acquisition part, 52 ... projection conversion part, 54 ... own vehicle position acquisition part, 56 ... recognition part, 58 ... setting part, 60 ... route acquisition part , 62 ... Trigger acquisition unit, 64 ... Guidance control unit, 66 ... Comparison unit, 68 ... Correction unit, 100 ... Parking support system, L1 ... Travel route, L2 ... Traveling track, T1 ... Movement target position, T2 ... Reference position ( Your vehicle position).

Claims (4)

A setting unit configured to set a target position of movement of the vehicle in a parking area defined by a pair of spaced apart marking lines included in an image output from an imaging unit that captures a situation around the vehicle;
A position acquisition unit for acquiring a current position of the vehicle;
A guidance control unit for guiding the vehicle to the movement target position based on the movement target position and the current position;
A first angle formed by a first direction extending along the lane marking extending direction through the movement target position and a second direction extending along the front-rear direction of the vehicle, and set in advance A comparison unit for comparing the second angle;
When the first angle is larger than the second angle, the lane marking closer to the vehicle is recognized among the pair of lane markings on the image, and the first angle is the second angle. A recognition unit that recognizes both of the pair of lane markings on the image in the following cases;
A correction unit that corrects at least one of the movement target position or the current position of the vehicle according to the recognition result of the lane marking;
A parking assistance device comprising:   The parking assistance device according to claim 1, wherein the guidance control unit displays an index indicating the parking area on a display device based on the movement target position and the current position. A route acquisition unit for acquiring a movement route for moving the vehicle based on the movement target position and the current position;
The parking assistance device according to claim 1 or 2, wherein the guidance control unit guides the vehicle to the movement target position according to the movement route based on the movement target position and the current position.   The parking assist device according to any one of claims 1 to 3, wherein the comparison unit executes a comparison process when a distance from the movement target position to the vehicle is equal to or less than a predetermined value.

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