JP7003755B2 - Parking support device - Google Patents

Description

An embodiment of the present invention relates to a parking support device.

Conventionally, a parking support device that supports a vehicle parking operation in a parking lot or the like is known. When, for example, a parking support device guides a vehicle into a parking area partitioned by a lane marking line (for example, a pair of white lines) in a parking lot and parks the vehicle, the parking support device first parks based on a photographed image of the surroundings of the vehicle. Search for and present possible parking area candidates. Then, when the parking area is selected by the driver or the system from the candidates, the 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 the vehicle is calculated. As a result, the driver or system can move the vehicle by guidance according to the movement path. The parking support device monitors the vehicle to reach the movement target position along the movement route while estimating the current position of the vehicle at any time based on the captured image and the detection signal from the wheel speed sensor, the steering angle sensor, or the like. .. Further, the parking support device, for example, detects a lane marking from the captured image at any time during the parking support, and corrects the movement target position or the like based on the detected lane marking.

Japanese Patent No. 4235526

In the case of the above-mentioned parking support device, during parking support, regardless of the distance from the vehicle to the lane marking or the posture of the vehicle with respect to the lane marking, the captured image can be detected at any time to detect what can be regarded as the lane marking or the lane marking. The movement target position, movement route, etc. are corrected based on the detection result. However, if the position of the vehicle is far from the lane marking, the lane marking may be small on the image, or the lane marking may be difficult to see on the image depending on the posture of the vehicle, and the lane marking cannot be recognized accurately (recognition). The accuracy may be low), or 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) at which the lane marking extends cannot be accurately detected. 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 rather corrected to an inappropriate state. For example, the parking area is tilted. In some cases, the vehicle was guided in a slanted posture.

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

The parking support 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 image pickup unit that captures the surrounding situation of the vehicle. Guidance to guide the vehicle to the movement target position based on the setting unit for setting the movement target position of the vehicle, the position acquisition unit for acquiring the current position of the vehicle, and the movement target position and the current position. A first angle formed by the control unit and a first direction extending along the extending direction of the lane marking through the movement target position and a second direction extending along the front-rear direction of the vehicle. A comparison unit that compares with a preset second angle, and a section closer to the vehicle among the pair of section lines on the image when the first angle is larger than the second angle. The recognition unit that recognizes a line and recognizes both of the pair of marking lines on the image when the first angle is equal to or less than the second angle, and the recognition result of the marking line, the above A correction unit for correcting at least one of the movement target position and the current position of the vehicle is provided.

According to this configuration, when the first angle is larger than the second angle, it can be regarded as, for example, a posture in which the vehicle is greatly tilted with respect to the first direction. In this case, there are lane markings on the image where the relative distance from the vehicle is short and easy to recognize accurately, and lane markings where the relative distance from the vehicle is far and the recognition accuracy is lower than the lane markings closer to the vehicle. .. In such a case, the closer lane marking with relatively high recognition accuracy is recognized, and at least one of the movement target position and the current position of the vehicle is corrected based on the lane marking. As a result, it is possible to reduce that the recognition result of the lane marking with low recognition accuracy affects the correction accuracy of the movement target position and the current position of the vehicle and is reflected in the parking support. On the other hand, when the first angle is equal to or less than the second angle, it can be considered that the inclination of the vehicle in the front-rear direction (second direction) is small with respect to the first direction. That is, it can be considered that the difference in the relative distance from the vehicle to the pair of lane markings defining the parking area is small, and the difference in the recognition accuracy of the pair of lane markings is small. In such a case, both lane markings can be treated in the same way, so that the size of the parking area such as the width and depth of the parking area can be grasped more accurately based on the recognition result of both lane markings. can. That is, it is possible to improve the accuracy of correcting the movement target position and the current position of the vehicle. As a result, it becomes possible to prevent the vehicle from being guided toward one of the lane markings in the parking area or being guided in a tilted posture in the parking area, so that the vehicle can be guided more appropriately in the parking area. Can be parked in position.

The guidance control unit of the parking support device according to the embodiment of the present invention may display, for example, an index indicating the parking area on the display device based on the movement target position and the current position. According to this configuration, a more accurate parking area can be provided to the driver.

The parking support device according to the embodiment of the present invention further includes, for example, a route acquisition unit that acquires a movement route for moving the vehicle based on the movement target position and the current position, and the guidance control unit includes the guidance control unit. Based on the movement target position and the current position, the vehicle may be guided to the movement target position according to the movement route. According to this configuration, for example, it is possible to acquire a movement route based on a movement target position based on a lane marking with higher recognition accuracy and the current position of the vehicle. As a result, it becomes possible to prevent the vehicle from being guided to one of the lane markings or being guided in a leaning posture in the parking area, and the vehicle is parked in a more appropriate position in the parking area. be able to.

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

FIG. 1 is a schematic plan view showing an example of a vehicle on which the parking support device according to the embodiment can be mounted. FIG. 2 is an exemplary block diagram of the configuration of a parking support system including the parking support device according to the embodiment. FIG. 3 is a diagram showing an example of a case where the parking support device according to the embodiment assists the parking of the vehicle, and is a schematic schematic diagram conceptually explaining the search of the parking area and the guidance of the vehicle by the movement route. be. FIG. 4 is a schematic diagram showing an example of an image captured by the image pickup unit of the parking support 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 support device according to the embodiment. FIG. 6 is an exemplary block diagram of the configuration of the CPU of the parking support device according to the embodiment. FIG. 7 is an example of parking support processing by the parking support device according to the embodiment, and is a flowchart illustrating an example of correcting a movement route by correcting a movement target position.

Hereinafter, exemplary embodiments of the present invention will be disclosed. The configurations of the embodiments shown below, as well as the actions, results, and effects produced by such configurations, are examples. The present invention can be realized by a configuration other than the configurations 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 support device of the present embodiment is mounted. The vehicle 10 may be, for example, an automobile (internal engine vehicle) driven by an internal combustion engine (engine, not shown), or an automobile (electric vehicle) driven by an electric motor (motor, not shown). , Fuel cell vehicle, etc.), or a vehicle (hybrid vehicle) using both of them as a drive source. Further, the vehicle 10 can be equipped with various transmission devices, and can be equipped with various devices (systems, parts, etc.) necessary for driving an internal combustion engine or an electric motor. In addition, the method, number, layout, and the like of the devices involved in driving 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 image pickup units 14a to 14d as a plurality of image pickup units 14. The image pickup unit 14 is, for example, a digital camera having a built-in image pickup element such as a CCD (Charge Coupled Device) or a CIS (CMOS image sensor). The image pickup 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 fisheye lens, respectively, and can photograph a range of, for example, 140 ° to 220 ° in the horizontal direction. Further, the optical axis of the image pickup unit 14 may be set diagonally downward. Therefore, the image pickup unit 14 is a road surface on which the vehicle 10 can move, an index (including a lane marking line indicating a parking area, a lane separation line, an arrow, etc.) or an object (as an obstacle, for example, a pedestrian, etc.). The surrounding environment outside the vehicle 10 including the vehicle) is sequentially photographed and output as captured image data.

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

The parking support device of the present embodiment recognizes (detects) a lane marking or the like by executing arithmetic processing or image processing based on the captured image data (images) obtained by the plurality of imaging units 14. Can be done. The parking support device searches for a parking area for parking the vehicle 10, sets a movement target position to be used when guiding the vehicle 10 to the parking area, and estimates the current position of the vehicle 10 by recognizing the lane marking. , Calculation of a movement route for guiding the vehicle 10 to the movement target position, and the like can be executed. By executing arithmetic processing and image processing based on the captured image data obtained by the plurality of imaging units 14, an image with a wider viewing angle can be generated, and the vehicle 10 can be moved upward, forward, sideways, or the like. It is possible to generate a virtual image (a bird's-eye view image (planar image), a side view image, a front view image, etc.) viewed from above.

FIG. 2 is an exemplary block diagram of the configuration of the parking support system 100 including the parking support device mounted on the vehicle 10. A display device 16 and a voice output device 18 are provided in the vehicle interior of the vehicle 10. The display device 16 is, for example, an LCD (liquid crystal display), an OELD (organic electroluminescent display), or the like. The audio output device 18 is, for example, a speaker. Further, the display device 16 is covered with a transparent operation input unit 20 such as a touch panel. The occupant (for example, the driver) can visually recognize the image displayed on the display screen of the display device 16 via the operation input unit 20. Further, the occupant may execute the operation input 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. can. The display device 16, the voice output device 18, the operation input unit 20, and the like are provided, for example, in the monitor device 22 located at the center of the dashboard of the vehicle 10 in the vehicle width direction, that is, 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 monitoring device 22 can also be used as, for example, a navigation system or an audio system.

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

The ECU 24 has, 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, a voice control unit 24e, an SSD 24f (solid state drive, flash memory), and the like. ing. The CPU 24a is, for example, a display device in addition to determining a moving target position of the vehicle 10 when executing parking assistance, estimating the current position of the vehicle 10, calculating a moving distance, calculating a target vehicle speed and a moving target position for each time, and so on. Various arithmetic processing and control such as image processing related to the image displayed in 16 can be executed.

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

As illustrated in FIG. 1, the vehicle 10 is, for example, a four-wheeled vehicle, and has two left and right front wheels 12F and two left and right rear wheels 12R. All of these four wheels 12 may 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 has 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 applies torque, that is, an assist torque to the steering portion (for example, the steering wheel) by the actuator 28b to supplement the steering force, or steers the wheels 12 by the actuator 28b. In this case, the actuator 28b may steer one wheel 12 or a plurality of wheels 12. Further, the torque sensor 28a detects, for example, the torque given to the steering portion by the driver.

The steering angle sensor 30 is, for example, a sensor that detects the steering amount of the steering unit. The steering angle sensor 30 is configured by using, for example, a Hall element or the like. The ECU 24 acquires the steering amount of the steering unit by the driver, the steering amount of each wheel 12 at the time of automatic steering, and the like from the steering angle sensor 30, and executes various controls. The steering angle sensor 30 detects the rotation angle of the rotating portion included in the steering portion.

The brake system 32, for example, has an ABS (anti-lock brake system) that suppresses brake lock, an electronic stability control (ESC) that suppresses sideslip of the vehicle 10 during cornering, and enhances braking force (ESC). An electric brake system (which 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. Further, the brake system 32 can execute various controls by detecting a brake lock, idling of the wheels 12, signs of skidding, etc. from the difference in rotation between the left and right wheels 12. The brake sensor 32a is, for example, a sensor that detects the position of a movable portion of a braking operation portion (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 amount of the engine and the output value of the motor according to the required operation amount (for example, the depression amount of the accelerator pedal) of the driver (user) detected by the accelerator sensor 36. .. Further, regardless of the operation of the user, the output value of the engine or the motor can be controlled in cooperation with the control of the steering system 28 and the brake system 32 according to the traveling state of the vehicle 10. The same applies when the vehicle 10 is traveling in the automatic traveling mode.

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

The shift sensor 38 is, for example, a sensor that detects the position of a movable portion of a shift operation unit (for example, a shift lever). The shift sensor 38 can detect the position of a lever, an arm, a button, or the like as a movable portion. 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 the forward travel request or the reverse travel request.

The wheel speed sensor 40 is a sensor provided on each wheel 12 to detect 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 may be configured by using, for example, a Hall element or the like. The ECU 24 calculates the vehicle speed, the amount of movement, and the like of the vehicle 10 based on the detection values 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. Take control. Further, when there is a wheel 12 having a detection value larger than that of the other wheels 12 among the four wheels, the ECU 24 has, for example, a rotation speed of a unit period (unit time or a unit distance) as compared with the other wheels 12. When there are more wheels 12 than a predetermined number, the wheels 12 are considered to be in a slip state (idle 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 configurations, arrangements, electrical connection forms, etc. of the various sensors and actuators described above are examples and can be set (changed) in various ways.

For example, the ECU 24 executes parking support processing based on the captured image data acquired from the imaging unit 14, and transmits data related to peripheral images and sounds generated based on the captured image data to the monitoring device 22.

The CPU 24a includes, for example, various modules as shown in FIG. 6, which will be described later, and executes, for example, a process related to parking support. For example, the CPU 24a executes arithmetic processing, image processing, and the like on the captured image data captured by the imaging unit 14 to search (present) a candidate for a parking area in which the vehicle 10 can park, 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, and 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 automatically or semi-automatically parks the vehicle 10 in the parking area while reducing the burden on the driver by the cooperation of hardware and software (control program). As a mode of parking support, the parking support system 100 executes steering operation, acceleration / deceleration operation, braking operation, etc. for guiding the vehicle 10 to the movement target position set in the parking area, and the driver starts support. There is "fully automatic parking support" that does not require any operation other than the operation of. In addition, "semi-automatic parking support" that entrusts the driver with at least one operation of the fully automatic parking support and the operation content of the vehicle 10 are 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 drive. In the following description, as an example, "fully automatic parking support" in which the vehicle 10 is moved backward and stored in the parking area will be described.

First, an outline of parking support will be described with reference to FIG. FIG. 3 is a diagram showing an example of a case where the parking support system 100 (parking support device) is used to support the parking of the vehicle 10, and conceptually explains the search for 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 division lines 44a and division lines 44b (hereinafter, referred to as division lines 44 when not distinguished) are arranged side by side (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 which 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 to allow parking of a general passenger car (for example, a vehicle 10). Be placed. The parking support system 100 searches for a parking area 42 that can be parked when the vehicle 10 travels at a parking area search speed or lower (for example, 30 km / h or less). In the case of FIG. 3, the parking support system 100 is 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 on the traveling locus L2). And the image pickup 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 executes image processing such as edge processing on the images captured while traveling, and also executes, for example, straight line detection, the division line 44a and the division line 44b and the like division line 44 and the division line 44 thereof. Recognize similar things. When a pair of lane markings 44a and lane markings 44b adjacent to each other at intervals wider than the vehicle width of the vehicle 10 are recognized, the area defined by the pair of lane markings 44a and the lane marking 44b is designated as the parking area 42. recognize. Further, the parking support system 100 registers the parking area 42 as a candidate for a parking area 42 that can be parked when an object such as another vehicle does not exist in the recognized parking area 42, and for example, the display device 16. Display and present to the driver.

When the driver selects a parking area 42 desired to be parked from the presented candidates for the parking area 42, the parking support system 100 moves to guide and accommodate the vehicle 10 in the selected parking area 42. Set the target position T1. In the parking support system 100, for example, in addition to the vehicle width and length of the vehicle 10, the division lines 44a obtained as a result of detecting the positions of the tip portions of the division lines 44a and 44b constituting the selected parking area 42 and the straight line detection. The movement target position T1 is set based on the direction (angle) in which the marking 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 fits in the selected parking area 42. It is set at the position where T2 exists. Therefore, the parking support system 100 calculates the movement path L1 connecting the reference position T2 indicating the current position of the vehicle 10 and the movement target position T1 by using a well-known technique, and the vehicle 10 is along the movement path L1. The vehicle 10 can be parked in the selected parking area 42 by guiding the vehicle 10 in reverse travel.

As described above, when searching for the parking area 42, the parking support system 100 recognizes the lane marking 44 in a state where the vehicle speed is relatively high. Therefore, the recognition accuracy of the lane marking 44a and the lane marking 44b may be low. Then, the movement target position T1 set at the start stage of the parking support is the size of the parking area 42 by performing straight line detection on the lane markings 44a and the lane markings 44b recognized in a state where the vehicle speed is relatively high. It is determined by estimating the position (tilt). As described above, when the lane markings 44a and 44b having low recognition accuracy are used, the setting accuracy of the movement target position T1 and the movement path L1 may not be high accuracy, and the vehicle 10 is placed at a predetermined position in the parking area 42. It may not be possible to guide to (for example, the center position without left-right bias). Therefore, the parking support system 100 of the present embodiment recognizes the lane marking 44 and performs arithmetic processing using the recognized lane marking 44 while the vehicle 10 is guided according to the movement path L1 and gradually approaches the parking area 42. Is 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 further, the correction of the movement path L1 is performed.

For example, when the guided running of the vehicle 10 is started based on the movement path 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 correct the position of the vehicle 10, the image pickup unit 14a installed at the rear of the vehicle 10 takes a picture of the surrounding situation. Then, the parking support system 100 starts re-recognizing the lane marking 44 based on the rear image. However, a wide-angle lens or a fisheye lens is used for each image pickup unit 14 mounted on the vehicle 10 including the rear image pickup unit 14a so as to enable a wide range of imaging. As a result, as shown in FIG. 4, the captured image 46 is an image in which the entire image is curved (an image in which a portion corresponding to the reflected rear bumper 10a, the horizon, the lane marking 44, or the like is curved). In this case, the object recognized in the image 46 (for example, the division line 44a or the division line 44b) appears smaller as it is farther from the image pickup unit 14a. When edge processing or straight line detection is performed on a small lane marking 44, it is difficult to expect high detection accuracy such as the position of the edge of the lane marking 44 and the direction (angle) of the lane marking 44. Further, depending on the relative relationship between the vehicle 10 and the lane marking 44, the recognition accuracy may differ between the lane marking 44 reflected near and the lane marking 44 reflected far away. As a result, the parking support system 100 recognizes a shape different from the actual state, for example, the parking area 42 in a curved state, or mistakenly recognizes the extending direction of the parking area 42 (section line 44). It may happen. In this case, the parking support system 100 may erroneously recognize the size and position of the parking area 42, and may improperly correct the movement target position T1, the reference position T2, and the movement path L1. be.

Therefore, the parking support system 100 of the present embodiment can secure higher recognition accuracy when it is determined that there is a difference in recognition accuracy with respect to the pair of lane markings 44 defining the selected parking area 42. It is configured to perform recognition correction of the movement target position T1 and the current position (reference position T2) of the vehicle 10 by using the lane marking 44 of the above, and further to correct the movement path L1. As an example, consider a situation in which the vehicle 10 faces the parking area 42 at the rear of the vehicle and tries to enter the parking area 42 by traveling backward, as shown in FIG. In such a situation, the first direction X extending in the length direction (extending direction of the lane marking 44) of the selected parking area 42 through the currently set movement target position T1 and the vehicle 10 The first angle θ, which is an acute angle among the angles extending along the front-back direction and formed in the second direction Y passing through the reference position T2, is detected. Then, by comparing the first angle θ with the second angle φ, which is an acute angle angle preset with respect to the first direction X, the posture of the vehicle 10 with respect to the lane marking 44 (with the vehicle 10). The difference in relative distance between the lane marking 44a and the lane marking 44b) is detected.

For example, as a result of comparison, when the first angle θ is larger than the second angle φ, the distance to the pair of lane markings 44 (section line 44a and lane marking 44b) with respect to the vehicle 10 (imaging unit 14a). Is different. As a result, the lane marking 44 farther from the vehicle 10 (for example, the lane marking 44b) has lower recognition accuracy than the lane marking 44 (for example, the marking line 44a) closer to the vehicle 10, and is erroneous when edge detection or straight line recognition is performed. The recognition rate exceeds the permissible range and is considered unsuitable for correcting the moving target position T1. In this case, the division line 44 (for example, division line 44a) closer to the vehicle 10 among the pair of division lines 44 (section line 44a and division line 44b) is used for correction control of the movement target position T1 and the reference position T2. Recognized as line 44.

On the other hand, when the first angle θ is equal to or less 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 division line 44a and the relative distance from the vehicle 10 (imaging unit 14a) to the division line 44b is reduced, and the division line 44a and the division line 44b are displayed on the image 46. Can be regarded as being reflected 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 can be improved. It can be considered that it does not make it worse. In this case, by recognizing the parking area 42 by the division line 44a and the division line 44b having a small difference in recognition accuracy, the recognition accuracy of the size and posture (angle) of the parking area 42 can be improved. Therefore, the movement target position T1 should be 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 running space PS (see FIG. 3) in the parking lot P. Can be done. Therefore, when the first angle θ is equal to or less than the second angle φ, the parking support system 100 recognizes both the pair of division lines 44a and the division line 44b as the division lines 44 used for the correction control of the movement target position T1. do.

For example, when the first angle θ is larger than the second angle φ, the lane marking 44a is recognized in the search range 48a on the near side of the vehicle 10. In this case, since the search range is limited to the vicinity side, it can contribute to reducing the load of image processing in the parking support system 100. When the first angle θ is equal to or less than the second angle φ, the lane marking 44a is recognized in the search range 48a on the near side of the vehicle 10, and the lane marking 44b is recognized in the search range 48b on the distant side of the vehicle 10. Do recognition. In this case, as described above, the pair of marking lines 44a and the marking line 44b makes it possible to recognize the parking area 42, and the recognition accuracy of the size 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 division line 44a or the division line 44b may be low. However, the difference in recognition accuracy 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 vehicle 10 recognizes the parking area 42 when searching for 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 also be low. Therefore, every time the parking support system 100 approaches the parking area 42 and the recognition accuracy of the lane marking 44 (the lane marking 44a or the lane marking 44b) is improved, the parking support system 100 uses the recognized lane marking 44 in the first direction X. May be modified. Further, the second angle φ differs depending on the performance of the image pickup unit 14, the mounting position in the vehicle 10, etc., but it is possible to evaluate and determine the recognition accuracy of the lane marking 44 due to the difference in the first angle θ by a test or the like in advance. can. The second angle φ can be, for example, “30 °”, 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. Various modules are realized by the CPU 24a installed in a storage device such as a ROM 24b, reading a stored program, and executing the program. For example, as shown in FIG. 6, the CPU 24a has an image acquisition unit 50, a projection conversion unit 52, a vehicle position acquisition unit 54, a recognition unit 56, a setting unit 58, a route acquisition unit 60, a trigger acquisition unit 62, and guidance control. It includes modules such as a unit 64, a comparison unit 66, and a correction unit 68. It should be noted 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 by integrating or separating each function described below. can.

The image acquisition unit 50 acquires the image captured by the image pickup unit 14 via the display control unit 24d. In the case of the present embodiment, when the search for the parking area 42 is performed, the side image of the vehicle 10 captured mainly by the image pickup units 14c and 14d is acquired, and when the parking support is received at the time of warehousing due to the backward traveling, the parking support is received. The rear image of the vehicle 10 captured mainly by the image pickup unit 14a is acquired. In another embodiment, when parking assistance is received at the time of warehousing by forward traveling, the front image of the vehicle 10 captured mainly by the image pickup unit 14b is acquired. The image acquisition unit 50 provides the acquired image to the projection conversion unit 52. The display control unit 24d may perform image processing such as distortion correction on the image captured by the image pickup unit 14 to display the image, display the image without image processing, or superimpose the image on other data. , The process may be performed by the display control unit 24d and displayed by 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 as to take a bird's-eye view of the parking area 42 as shown in FIGS. 3 and 5. Convert to a 3D image.

The own vehicle position acquisition unit 54 acquires the current position (own 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 image pickup unit 14a and the center position of the rear wheel axle 12a in the vehicle width direction is known. Therefore, when the projection conversion unit 52 projects and converts the image captured by the image pickup unit 14a, the position of the reference position T2 can be determined on the three-dimensional coordinates. Similarly, the relationship between the mounting positions of the image pickup unit 14c and the image pickup unit 14d and the center position of the rear wheel axle 12a in the vehicle width direction is known. Therefore, the own vehicle position acquisition unit 54 is the current position of the vehicle 10 with respect to the reference point (for example, the origin) determined on the projected and transformed three-dimensional coordinates acquired at the time of searching the parking area 42 or after the parking support is started. The position can be acquired sequentially.

The recognition unit 56 performs edge processing, for example, linear detection processing, or the like on the projected and transformed image to recognize the division line 44. As described above, when searching for the parking area 42, the recognition accuracy of the lane marking 44 by the recognition unit 56 is not very high. On the other hand, by executing the parking support, the recognition result of the lane marking 44 is sequentially updated in the process of the vehicle approaching the selected parking area 42, and the recognition accuracy of the lane marking 44 by the recognition unit 56 is improved. Further, the recognition unit 56 searches for an area having a frontage that can be used as the parking area 42 by calculating the relative distance (separation distance) of the adjacent division lines 44 with respect to the recognized division line 44. .. Based on the recognition result of the lane marking 44, the recognition unit 56 recognizes the pair of lane markings 44 adjacent to each other at intervals wider than the vehicle width of the vehicle 10, and the recognition unit 56 recognizes the pair of lane markings 44 (the lane marking 44a and the marking line 44a). The area defined in 44b) is referred to as a parking area 42. Further, when the detected parking area 42 does not have an object (obstacle) such as another vehicle, the recognition unit 56 registers the parking area 42 as a candidate for a parkingable area 42. Then, the recognition unit 56 displays the information of the registered parking area 42 on the display device 16 via the display control unit 24d and presents it to the driver. When displaying the candidate of the parking area 42, the display control unit 24d may display a message for the driver to select one of the candidates. When the vehicle 10 is provided with 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 measuring result, and can use the parking area 42. You may decide the candidate of.

The setting unit 58 sets the movement target position T1 in the selected parking area 42 based on the pair of division lines 44a and the division line 44b that define the parking area 42 selected by the driver. The movement target position T1 is a position where 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, a midpoint position in the separation direction between the pair of lane markings 44a and the lane marking 44b detected in a straight line. Further, the position of the parking area 42 of the movement target position T1 in the depth direction is, for example, from the tip of the vehicle 10 (front bumper 10b) to the reference position T2 with reference to the tip portion 44c on the entrance side of the recognized lane marking 44. It can be a position corresponding to the distance of. Even if the setting unit 58 automatically selects a parking area 42 that satisfies the preset conditions from the candidates for the parking area 42 presented by the recognition unit 56, and sets the movement target position T1. good.

The route acquisition unit 60 is a well-known recommended movement route calculation technique based on the movement target position T1 set based on the division 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 movement path L1.

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

The guidance control unit 64 guides the vehicle 10 based on the movement target position T1 and the reference position T2 which is the current position of the vehicle 10, that is, guides the vehicle 10 to move along the movement route L1 acquired by the route acquisition unit 60. To execute. When executing the "fully automatic parking support", the guidance control unit 64 controls the steering system 28, the brake system 32, the drive system 34, etc., and causes the vehicle 10 to travel backward along the movement path L1 as a reference. The position T2 is brought closer to the movement target position T1. In the case of "semi-automatic parking support" or "guidance support", the parking operation is performed by providing the operation content to the driver by voice or display and the driver performing a part or all of the operation.

As described with reference to FIG. 5, the comparison unit 66 passes through the movement target position T1 and extends in the length direction of the parking area 42 (extending direction of the lane marking 44) in the first direction X and in the front-rear direction of the vehicle 10. The first angle θ formed by the second direction Y extending along the reference position T2 and passing through the reference position T2 is compared with the preset second angle φ. As described above, since the linear detection of the division line 44 is executed every time the recognition unit 56 re-recognizes the division line 44, 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 with the movement of the vehicle 10, the second direction Y is updated. Therefore, the comparison unit 66 can compare the first angle θ and the second angle φ in the recognition cycle of the division line 44 by the recognition unit 56, for example. The comparison unit 66 provides the result of the comparison 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 moving target position T1 to the vehicle 10 (distance to the reference position T2) exceeds a predetermined value (for example, 6 m), improvement in recognition accuracy is expected even on the lane marking 44 on the side closer to the vehicle 10. It is determined that the movement target position T1 cannot be reset, and the recognition of the lane marking 44 for resetting is temporarily stopped. In this case, since the movement target position T1 is not reset, 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 always necessary, and there is no inconvenience even if the movement path L1 based on the movement target position T1 set at the time of search is used as it is. Can be regarded. In this way, by adding the 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 the movement path L1 is deteriorated. It is possible to prevent the correction from being carried out. Further, it can contribute to the reduction of the processing load of the parking support system 100. Then, the guidance control unit 64 guides the vehicle 10 by using the movement path 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 the vehicle becomes a predetermined value or less. To do so. After that, 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 division line 44 is to be recognized.

The correction unit 68 causes the recognition unit 56 to re-recognize the lane marking 44 based on the comparison result of the comparison unit 66, and the setting unit 58 corrects (re-recognizes) the movement target position T1 based on the re-recognition result. Setting) is executed. 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 vehicle 10 out of the pair of lane markings 44 It is determined that the nearer division line 44 (in the case of FIG. 5, the division line 44a) can perform edge processing and straight line detection with higher accuracy than the farther division line 44 (in the case of FIG. 5, the division line 44b). .. Therefore, the correction unit 68 causes the recognition unit 56 to re-recognize the division line 44 (section line 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 more likely to be recognized more accurately. For example, the setting unit 58 offsets the position of the movement target position T1 in the parking area 42 in the width direction from the recognized lane marking 44a toward the inside of the parking area 42 by a distance of ½ of the vehicle width of the vehicle 10 and a predetermined amount. 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, for example, 150 mm. It should be noted that the parallelism with respect to the lane marking 44 can be improved by resetting the first direction X based on the lane marking 44a closer to the vehicle 10, which is more likely to be recognized more accurately. .. As a result, it is possible to improve the comparison accuracy when comparing the first angle θ and the second angle φ in the next control cycle.

On the other hand, when the correction unit 68 obtains a result indicating that the first angle θ is equal to or less than the second angle φ as the comparison result of the comparison unit 66, both of the pair of division lines 44 (the division lines 44a and the division line 44a). It is determined that the lane marking 44b) enables edge processing and straight line detection 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, it is determined that the difference in recognition accuracy between the lane markings 44a and the lane markings 44b is small, and that edge processing and straight line detection are possible with the same degree of accuracy. Then, the correction unit 68 causes the recognition unit 56 to re-recognize the lane marking 44 (section line 44a) in the search range 48a, and re-recognizes the lane marking 44 (section line 44b) in the search range 48b. Perform recognition. As a result, the setting unit 58 can reset the movement target position T1 based on the division line 44a and the division line 44b that can secure the same recognition accuracy. In this case, the accuracy of setting 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 of the lane markings 44. It should be noted that the first direction X is also set again based on the pair of lane markings 44a and 44b, so that it is parallel to the lane marking 44 as compared with the case where only one lane marking 44 (section line 44a) is set. The degree can be improved. As a result, it is possible to improve the comparison accuracy when comparing the first angle θ and the second angle φ in the next control cycle.

Further, the correction unit 68 corrects (resets) the movement path L1 based on the movement target position T1 newly recognized by the route acquisition unit 60 according to the comparison result of the comparison unit 66. To execute. 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 own vehicle position reset by the setting unit 58 in the route acquisition unit 60 using the lane marking 44a. Using the current position (reference position T2) of the vehicle 10 acquired by the acquisition unit 54, the correction (resetting) of the movement path L1 is executed. In this case, it is possible to set the movement target position T1 whose position accuracy is improved with respect to the actual division line 44 (section line 44a) from the movement target position T1 initially set when the vehicle 10 searches the parking area 42. Therefore, the accuracy of the movement path L1 set based on the movement target position T1 can be improved. Similarly, when the first angle θ is equal to or less than the second angle φ, the correction unit 68 sets the movement target position reset by the setting unit 58 in the route acquisition unit 60 using the division line 44a and the division line 44b. Using the current position (reference position T2) of the vehicle 10 acquired by T1 and the own vehicle position acquisition unit 54, the correction (resetting) of the movement path L1 is executed. In this case, the position accuracy is higher than the movement target position T1 initially set when the vehicle 10 searches the parking area 42 or the movement target position T1 reset using only the lane marking 44a with respect to the actual lane marking 44. The improved movement target position T1 can be set. Therefore, the accuracy of the movement path L1 set based on the movement target position T1 can be further improved. Therefore, the vehicle 10 can be parked at a more ideal position in the parking area 42, that is, at a position in the parking area 42 that secures an appropriate gap in the front, rear, left, and right of the vehicle 10.

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 image pickup unit 14 of the vehicle 10 normally constantly captures an image of the surroundings of the vehicle 10, but when the vehicle is traveling at, for example, 30 km / h (parking area search speed) or less, the parking support system 100 operates. It is considered that the person is driving while finding a parking space. Then, the parking support system 100 acquires a peripheral image of the vehicle 10 by, for example, the image pickup unit 14c and the image pickup unit 14d in order to search the parking area 42 as a preparatory step for parking support (S100).

The projection conversion unit 52 performs sequential projection conversion processing on the 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 for, and the search result is displayed (presented) on the display device 16 (S102). When a specific parking area 42 is not selected from the candidates of the parking area 42 presented by the driver or the setting unit 58 (No of S104), the process returns to S100 and the parking area 42 based on the newly acquired image is used. Repeat the presentation of candidates.

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 the temporary (initial) movement target position T1 (S106). Further, the own vehicle position acquisition unit 54 acquires a reference position T2 that can be regarded as the position of the vehicle 10 (current own vehicle position) when the movement target position T1 is provisionally 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).

Then, the trigger acquisition unit 62 confirms whether or not the trigger signal for starting the parking support process has been received (acquired) (S112). If the trigger acquisition unit 62 has not received the trigger signal (No in S112), the process returns to S108. As a result, the own vehicle position acquisition unit 54 reacquires 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 movement target position T1.

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

Then, the correction unit 68 causes the setting unit 58 to perform correction (resetting) of the movement target position T1 based on the recognized division line 44 (S122). Further, the correction unit 68 moves 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 of the comparison unit 66. The correction (resetting) of L1 is executed (S124).

The guidance control unit 64 executes guidance of the vehicle 10 based on the corrected (reset) movement path L1 (S126), and the position of the reference position T2 acquired by the vehicle position acquisition unit 54 (vehicle position). If has not reached the movement target position T1 (No in S128), the process of S114 returns, and the subsequent processes are repeated. Further, when the position (own vehicle position) of the reference position T2 acquired by the own vehicle position acquisition unit 54 has reached (can be regarded as) the movement target position T1 (Yes in S128), the guidance control unit 64 has a series of parking. 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.

When the recognition unit 56 determines in the process of S114 that the distance from the movement target position T1 to the vehicle (distance to the reference position T2) is not equal to or less than the lane marking recognition start distance (No in S114). Skipping the processes of S116 to S124, the guidance control unit 64 guides the vehicle 10 based on the currently set movement path L1 and determines whether the reference position T2 has reached the movement target position T1. (S128) If it has not been reached, the processing after S114 is executed.

In this way, when the first angle θ is larger than the second angle φ, the movement target position T1 and the movement path L1 can be reset using the lane marking 44 that can improve the recognition accuracy on the near side of the vehicle 10. .. As a result, it is possible to guide the vehicle 10 by the movement path L1 in which additional guidance control such as turning is unlikely to occur. Further, when the first angle θ is equal to or less than the second angle φ, the movement target position T1 and the movement are performed using both division lines 44 (partition line 44a and division line 44b) that can be recognized with little difference in accuracy. The route L1 can be reset. As a result, the position accuracy is higher than the movement target position T1 temporarily set when the vehicle 10 searches the parking area 42 or the movement target position T1 reset using only the lane marking 44a with respect to the actual lane marking 44. The improved movement target position T1 can be set. Therefore, the accuracy of the movement path L1 set based on the movement target position T1 can be further improved. That is, the vehicle 10 can be guided to a more ideal position in the parking area 42 and parked. That is, in the parking area 42, it becomes possible to prevent the vehicle 10 from being guided toward one of the lane markings 44 or being guided in the parking area 42 in an inclined posture, and the vehicle 10 can be guided to the parking area 42. Within, it is possible to realize parking at a more appropriate position with appropriate gaps secured on the front, back, 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 marking 44 to be recognized based on the comparison between the first angle θ and the second angle φ, and moves based on the recognized lane marking 44. An example of correcting (resetting) the target position T1 and then resetting the movement path L1 is shown. In this case, along with the improvement of the accuracy of the movement target position T1, the setting accuracy of the movement path 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 marking 44 to be recognized based on the comparison between the first angle θ and the second angle φ, and the own vehicle position of the vehicle 10 based on the recognized lane marking 44. The movement path L1 may be reset by re-detecting (current position, reference position T2). In the case of the above example, the current position (reference position T2) of the vehicle 10 is determined by the image pickup unit 14 by using the detection signal from the wheel speed sensor 40, the steering angle sensor 30, etc., regardless of the recognition of the lane marking 44. An error occurs when the position changes due to vibration or the like. On the other hand, by recognizing the lane marking 44 based on the image captured by the image pickup 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 obtained. Maintenance and improvement are possible. With the improvement of the accuracy of the reference position T2 with respect to the lane marking 44, it is possible to improve the setting accuracy of the movement path L1 based on the reference position T2, and it is possible to improve the guidance accuracy of the vehicle 10. ..

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 portion 44c (see FIG. 5) of the recognized lane marking 44. The current position of the vehicle 10 (reference position T2) may be detected. In this case, the correction unit 68 enables the own vehicle position acquisition unit 54 to detect the current position of the vehicle 10 with respect to the lane marking 44 having 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 path L1 determined by using the movement target position T1 and the current position (reference position T2) of the vehicle 10 (S124). Then, the guidance control unit 64 performs guidance control of the vehicle 10 (S126). As a result, the setting accuracy of the movement path L1 is improved and the guidance accuracy of the vehicle 10 can be improved, as in the case of the movement path L1 which is reset using the corrected movement target position T1. Even when the current position of the vehicle 10 is detected, both lane markings 44 (lane lane 44a, lane marking 44b) are used rather than only the lane marking 44 (lane marking 44a) on the near side of the vehicle 10. 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 having high recognition accuracy may be performed. The movement path L1 may be reset according to the target position T1 and the reference position T2. In this case, it is possible to further improve the setting accuracy of the movement path L1, and the vehicle 10 is guided to one of the lane markings 44 in a biased manner or is guided in the parking area 42 in an inclined posture. Is more suppressed.

In the above-described embodiment, the guidance control unit 64 has described an example in which the vehicle 10 is guided to the movement target position T1 based on the movement path L1 acquired (set and reset) by the route acquisition unit 60. In another embodiment, the guidance control unit 64, as an example of the guidance process of the vehicle 10, is an index indicating the parking area 42 to be guided based on the movement target position T1 and the current position (reference position T2) 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 the division line 44 (44a, 44b) of the parking area 42 to be guided or is displayed inside the division line 44 (44a, 44b). Can be. The "parking frame" may be a rectangular frame entirely surrounded by a diagram or the like, a frame showing only the parts corresponding to the four corners of the parking frame, or conversely a frame displaying only the side parts other than the four corners. But it may be. In this case, 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 is improved based on the lane marking 44 re-recognized by the recognition unit 56. An index (for example, a parking frame) indicating the parking area 42 can be displayed at a more accurate position with respect to the vehicle 10 on the display device 16. As a result, when the vehicle 10 is guided, it is easy for the driver to grasp a more accurate parking position, and it is easy 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 the diagram.

Further, in the above-described embodiment, the parking support at the time of backward parking in which the vehicle 10 enters the parking area 42 while traveling backward has been described. In another embodiment, when the vehicle 10 enters the parking area 42 while traveling forward, the lane marking 44 is similarly recognized, and at least one of the correction of the movement target position T1 and the detection of the reference position T2 is performed. , And parking support may be provided while resetting the movement route L1, and the same effect can be obtained.

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

In the above-described embodiment, the marking line 44 shows an example of being painted on the parking road surface, but the present invention is not limited to this, and any marking line 44 may be used as long as it can be recognized by performing image processing on the captured image. For example, this embodiment can be applied even when a lane marking is formed by a rope or the like, and the same effect can be obtained.

The program for parking support processing executed by the CPU 24a of the present embodiment is a file in an installable format or an executable format, and is a CD-ROM, a flexible disk (FD), a CD-R, or a DVD (Digital Versatile Disk). It may be configured to record and provide on a recording medium readable by a computer such as.

Further, the parking support processing program may be configured to be provided by storing it on a computer connected to a network such as the Internet and downloading it via the network. Further, the parking support processing program executed in the present embodiment may be configured to be provided or distributed via a network 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 embodiments, and various omissions, replacements, and changes can be made without departing from the gist of the invention. These embodiments and variations thereof are included in the scope and gist of the invention, and are also included in the scope of the invention described in the claims and the equivalent scope thereof.

10 ... vehicle, 12a ... rear wheel shaft, 14, 14a, 14b, 14c, 14d ... image pickup unit, 16 ... display device, 24 ... ECU, 24a ... CPU, 42 ... parking area, 44, 44a, 44b ... lane marking, 44c ... tip, 46 ... image, 48a, 48b ... search range, 50 ... image acquisition unit, 52 ... projection conversion unit, 54 ... vehicle position acquisition unit, 56 ... recognition unit, 58 ... setting unit, 60 ... route acquisition unit , 62 ... Trigger acquisition unit, 64 ... Guidance control unit, 66 ... Comparison unit, 68 ... Correction unit, 100 ... Parking support system, L1 ... Movement route, L2 ... Travel locus, T1 ... Movement target position, T2 ... Reference position ( Own vehicle position).

Claims (4)

A setting unit that sets the movement target position of the vehicle in a parking area defined by a pair of lane markings arranged apart from each other, which is included in the image output from the image pickup unit that captures the surrounding situation of the vehicle.
A position acquisition unit that acquires the current position of the vehicle, and
A guidance control unit that guides the vehicle to the movement target position based on the movement target position and the current position.
A preset angle and a first angle formed by a first direction extending along the extending direction of the lane marking and a second direction extending along the front-rear direction of the vehicle through the movement target position. A comparison section that compares with the second angle,
When the first angle is larger than the second angle, the lane marking line closer to the vehicle among the pair of lane markings on the image is recognized, and the first angle is the second angle. In the following cases, a recognition unit that recognizes both of the pair of marking lines on the image, and a recognition unit.
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.
Parking support device equipped with. The parking support 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. Further, a route acquisition unit for acquiring a movement route for moving the vehicle based on the movement target position and the current position is provided.
The parking support 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 support device according to any one of claims 1 to 3, wherein the comparison unit executes a comparison process when the distance from the movement target position to the vehicle is equal to or less than a predetermined value.

Images