Parking assistance device and control method for parking assistance device

Abstract

The present application can determine a parking path that is favorable for improving the ride, comfort. The parking assistance device (100) calculates, by the parking path calculation section (115), a plurality of modes of parking paths that differ in the radius of curvature of a circular arc included in the parking path, using vehicle information (122) and the recognition result of the surrounding recognition section (111), as a parking path for parking the vehicle (1) in a parking area. In addition, the parking assistance device (100) selects, by the parking path selection section (116), a parking path in which the number of times of the driving operation of changing the traveling direction of the vehicle (1) from forward to reverse, or from reverse to forward, is the least, and the radius of curvature of the circular arc is the largest, from among the plurality of modes of parking paths.

Description

TECHNICAL FIELD

[0001] The present application relates to a parking assistance device and a control method for a parking assistance device. BACKGROUND

[0002] As a technology related to automatic parking, there is patent literature 1.

[0003] In the abstract of patent literature 1, it is described that "a parking frame position acquisition unit 21 acquires one or a plurality of parking frame positions from images of cameras 3 to 6 mounted on a vehicle. An evaluation unit 24 evaluates an operation burden of a driver with respect to a plurality of parking paths, and a parking path selection unit 25 selects a parking path having the smallest operation burden of the driver based on the evaluation result, and displays it on a vehicle-mounted monitor 13."

[0004] In this patent literature 1, "the parking path selection mechanism selects a parking path having the smallest number of forward-rearward switching" and "the parking path selection mechanism selects a parking path having the smallest steering operation amount from among parking paths having the smallest number of forward-rearward switching in a case where the parking path having the smallest number of forward-rearward switching is a plurality of parking paths."

[0005] Prior Art Documents

[0006] Patent Literature

[0007] Patent literature 1: Japanese Patent Application Publication No. 2011-46335 SUMMARY

[0008] Problems to be Solved by the Invention

[0009] In the technology of patent literature 1, in a case where a plurality of parking frames are acquired, parking paths to each of the parking frames are generated, and a parking path having the smallest operation burden of the driver is generated from among them. Therefore, in a case where only one parking frame is acquired, there is a possibility that a parking path having a large rudder angle and a parking path having a large number of forward-rearward switching are generated, which affects the ride comfort of the occupant.

[0010] In addition, in patent literature 1, the curved portion of the parking path is made to be a path in which a basic clothoid curve is similar to an enlarged path. Therefore, the radius of curvature of the curved portion depends on the similar enlargement rate, and it is not possible to increase the radius of curvature in order to improve the ride comfort or the like.

[0011] An object of the present application is to provide a parking assistance device and a control method for a parking assistance device that can determine a parking path that is advantageous for improving the ride comfort and the like.

[0012] Means for Solving the Problems

[0013] One aspect of the present application is a parking assistance device characterized by comprising: a surrounding recognition unit that recognizes information of a surrounding of a vehicle; a parking area detection unit that detects a parking area in which the vehicle can park, using a recognition result of the surrounding recognition unit; a parking path calculation unit that calculates, as a parking path in which the vehicle stops in the parking area, a parking path in which a curvature radius of a circular arc included in the parking path is different in a plurality of modes, using information of the vehicle and the recognition result of the surrounding recognition unit; and a parking path selection unit that selects, from the plurality of modes of the parking path, a parking path in which a number of times of a driving operation of changing a traveling direction from forward to reverse or from reverse to forward of the vehicle is the least and a curvature radius of the circular arc is the largest.

[0014] Effects of the Invention

[0015] According to the present application, it is possible to determine a parking path that is advantageous for improving a ride feeling, comfort. BRIEF DESCRIPTION OF DRAWINGS

[0016] Figure 1 is a view showing a configuration of a vehicle on which a parking assistance device of an embodiment of the present application is mounted.

[0017] Figure 2 is an explanatory view of a parking area.

[0018] Figure 3 is a flowchart of a parking assistance process.

[0019] Figure 4 is an explanatory view of a parking path.

[0020] Figure 5 is an explanatory view of a comparative example.

[0021] Figure 6 is an explanatory view of an embodiment of the present application.

[0022] Figure 7 is a flowchart of a parking assistance process of a modified example.

[0023] Explanation of Reference Signs

[0024] 1 vehicle

[0025] 2, 3 other vehicle

[0026] 5 in-vehicle network

[0027] 10 surrounding detection sensor unit

[0028] 10A sonar

[0029] 10B camera

[0030] 20 vehicle sensor unit

[0031] 30 vehicle control device

[0032] 100 parking assistance device

[0033] 110 position detection section

[0034] 111 peripheral recognition section

[0035] 111A peripheral information acquisition section

[0036] 111B obstacle detection section

[0037] 111C map generation section

[0038] 113 parking area detection section

[0039] 114 parking frame setting section

[0040] 115 parking path calculation section

[0041] 116 parking path selection section

[0042] 117 automatic travel control section

[0043] 120 storage section

[0044] 121 control program

[0045] 122 vehicle information

[0046] Q parking area

[0047] R radius of curvature

[0048] Ra upper limit value of the radius of curvature R

[0049] Rb lower limit value of the radius of curvature R

[0050] D1, D2 parking path

[0051] C1, C2 circle along the circular arc in the parking path

[0052] P1, P2 center of the circle

[0053] DC, DCa, DCb curve

[0054] DCb circular arc

[0055] CL1, CL2, CL1a, CL2a, CL1b, CL2b clothoid curve DETAILED DESCRIPTION

[0056] Embodiments of the present application will be described below with reference to the accompanying drawings.

[0057] Figure 1 is a view showing the configuration of a vehicle 1 equipped with the parking assistance device 100 of the present embodiment.

[0058] The vehicle 1 includes a surrounding detection sensor section 10, a vehicle sensor section 20, a vehicle control device 30, and the parking assistance device 100, which are connected in a manner enabling data communication by means of a vehicle-mounted network 5 such as a CAN (Controller Area Network) bus.

[0059] The surrounding detection sensor section 10 is provided with various sensors for detecting information on the surroundings of the vehicle 1, and outputs the detection results (outputs) to the parking assistance device 100. Hereinafter, the information on the surroundings will be referred to as "surrounding information".

[0060] The surrounding information includes information on objects existing in the surroundings of the vehicle 1, such as obstacles, boundary lines dividing the parking area of the vehicle 1, and the like. The obstacles are various objects that obstruct the travel of the vehicle 1. As typical examples of the obstacles, there can be mentioned structures such as pillars, walls, and fire hydrants, other vehicles and pedestrians in the process of parking or traveling.

[0061] The surrounding detection sensor section 10 of the present embodiment includes a sonar 10A and a camera 10B.

[0062] The sonar 10A is a distance measuring sensor that detects obstacles in the surroundings using sound waves and measures the distance between the obstacles and the vehicle 1. The sonar 10A is provided at the left and right of the vehicle 1 or the like, and can detect objects and the like around the parking area Q in which the vehicle 1 is to be parked. Note that, instead of the sonar 10A, other distance measuring sensors such as a radar or a Lidar (Laser Imaging Detection and Ranging) can be used.

[0063] The camera 10B functions as an imaging section that images the surroundings of the vehicle 1. The camera 10B is provided so as to be able to image the front, rear, left, and right of the vehicle 1, and can image the parking area Q existing in the surroundings of the vehicle 1. Note that the camera 10B can be a camera provided separately at the front, rear, left, and right of the vehicle 1 or the like, or a camera that can image the front, rear, left, and right using one camera.

[0064] The vehicle sensor section 20 has sensors that acquire information on each part of the vehicle 1, and can detect various information required for travel state detection and autonomous navigation (dead reckoning) of the vehicle 1. For example, the vehicle sensor section 20 has a gyro sensor, an acceleration sensor, a vehicle speed sensor, a steering angle sensor that detects the steering angle of the vehicle 1, and the like.

[0065] The vehicle control device 30 controls the steering device, the drive device, and the brake control device of the vehicle 1 to cause the vehicle 1 to move by itself (automatic travel) based on a parking route to be described later, which is calculated by the parking assistance device 100. The vehicle control device 30 has a computer (for example, an ECU (Electronic Control Unit)) that executes the control. Note that the steering device includes an actuator that steers the steering wheel of the vehicle 1.

[0066] In addition, the drive device includes an actuator that adjusts the driving force of the driving wheel of the vehicle 1. In the case where the power source of the vehicle 1 is an engine, the actuator of the drive device is a throttle adjuster. In the case where the power source is a motor, the actuator of the drive device is the motor of the power source.

[0067] The brake control device has an actuator that controls the brake system provided to the vehicle 1, and controls the braking force of the vehicle 1 by the actuator.

[0068] The parking assistance device 100 is a device that causes the vehicle 1 to automatically travel to the parking area Q to assist the parking of the vehicle 1.

[0069] The parking assistance device 100 includes a processor (corresponding to the computer of the present application) such as a CPU (Central Processing Unit), an MPU (Microprocessor Unit), a storage device (corresponding to the storage section 120 of the present application) such as an HDD (Hard Disk Drive), an SSD (Solid State Drive), an interface circuit for connecting sensors, external devices, and the like, and an in-vehicle network communication circuit that communicates with other in-vehicle devices via the in-vehicle network 5. Figure 1 The parking assistance device 100 realizes the various functional structures shown in FIG. 1 by executing the control program 121 stored in the storage section 120 by the processor. Figure 1

[0070] That is, the parking assistance device 100 includes the position detection section 110, the surrounding recognition section 111, the parking area detection section 113, the parking frame setting section 114, the parking route calculation section 115, the parking route selection section 116, the automatic travel control section 117, and the storage section 120 as functional structures.

[0071] The position detection section 110 detects the current position (self-position) of the vehicle 1 based on the detection result (output) of the vehicle sensor section 20 using a publicly known or well-known dead reckoning method.

[0072] ​The surrounding recognition unit 111 includes a surrounding information acquisition unit 111A, an obstacle detection unit 111B, and a map generation unit 111C. The surrounding information acquisition unit 111A acquires information of a detection target object in the surrounding of the vehicle 1 on the basis of a detection result of the surrounding detection sensor unit 10. For example, a demarcation line or the like that divides a parking area of the vehicle 1 is detected by image recognition of an image of the camera 10B, and a position of the demarcation line or the like with the vehicle 1 as a reference is detected. The obstacle detection unit 111B detects an obstacle in the surrounding of the vehicle 1 on the basis of a detection result of the surrounding detection sensor unit 10. For example, an obstacle in the surrounding is detected on the basis of a detection result of the sonar 10A, and a position of the obstacle with the vehicle 1 as a reference is detected.

[0073] The map generation unit 111C generates map data on the basis of detection results of the surrounding information acquisition unit 111A and the obstacle detection unit 111B. The map data is data in which positions of obstacles and the like are recorded in a local space coordinate system with a current position of the vehicle 1 at an appropriate timing as an origin. The surrounding recognition unit 111 can recognize surrounding information related to travel (including parking) of the vehicle 1 by using the surrounding information acquisition unit 111A, the obstacle detection unit 111B, and the map generation unit 111C and on the basis of a detection result (output) of the surrounding detection sensor unit 10. Note that a technique of recognizing surrounding information related to travel of the vehicle 1 can widely use a known technique.

[0074] The parking area detection unit 113 detects a parking area Q in which the vehicle 1 is parked on the basis of surrounding information recognized by the surrounding recognition unit 111. Here, Figure 2 a case in which a parking frame between the other vehicles 2 and 3 is recognized as the parking area Q is exemplified. A method of detecting the parking area Q on the basis of surrounding information can use a known or well-known technique. For example, the parking area detection unit 113 recognizes a rectangular area in which the vehicle 1 can be parked in size on the basis of a distribution of obstacles represented by the map data, and detects the area as the parking area Q. Alternatively, for example, the parking area detection unit 113 detects the parking area Q by recognizing a demarcation line of the parking area by using image recognition with respect to a captured image of the camera 10B.

[0075] In a case where the parking area Q is detected, the parking area detection unit 113 converts a position of the parking area Q in the captured image to a position of the local space coordinate system of the map data by projection conversion from a 2-dimensional coordinate system of the captured image to the local space coordinate system of the map data. The projection conversion can be performed using a known or well-known appropriate technique. By the projection conversion to the local coordinate system, the position of the parking area Q is determined.

[0076] The parking frame setting section 114 sets a rectangular parking frame that defines a range in which the vehicle 1 is accommodated at the time of parking, in the parking area Q based on the parking area Q detected by the parking area detection section 113. Note that, in the case where the parking area Q is a parking area divided by a boundary line, the parking frame setting section 114 sets the boundary line as the parking frame.

[0077] The parking route calculation section 115 is a portion of a parking route calculation function that calculates a parking route to the parking area Q based on the current position of the vehicle 1. The parking route calculation section 115 of the present embodiment calculates a parking route in which the vehicle 1 parks toward the parking area Q from the current position backward based on the map data. In calculating this parking route, the parking route calculation section 115 can calculate a plurality of modes of parking routes by making the radius of curvature (may also be referred to as the turning radius) R of the circular arc included in the parking route different. In other words, the parking route calculation section 115 has a parking route calculation function that calculates a parking route including a circular arc of a specified radius of curvature R.

[0078] Note that, depending on the value of the radius of curvature R, there is a possibility that a parking route including a circular arc of the corresponding radius of curvature R cannot be calculated at the time of, for example, one forward-backward switching. Therefore, the parking route calculation section 115 is configured so that it can calculate a parking route including a circular arc of a specified radius of curvature R as much as possible by appropriately changing the number of forward-backward switching.

[0079] As such, the parking route calculation section 115 can calculate a plurality of modes of parking routes in which the radius of curvature R of the circular arc in the parking route is different and the number of forward-backward switching in the parking route is appropriately different.

[0080] Note that, forward-backward switching refers to a driving operation in which the vehicle 1 changes the traveling direction from forward to backward or from backward to forward in order to change the angle of entry of the vehicle 1 into the parking area Q, and is also referred to as a U-turn route.

[0081] The parking route selection section 116 extracts a parking route in which the number of forward-backward switching is the least among the parking routes calculated by the parking route calculation section 115, and selects a parking route in which the radius of curvature R of the circular arc in the parking route is the largest from among the extracted parking routes. By selecting a parking route in which the number of forward-backward switching is the least and the radius of curvature R is the largest, it is possible to select a route in which the external force that causes the occupant to sway forward and backward or left and right is suppressed at the time of parking, or a route in which the degree of suppression of the external force itself is suppressed, which is advantageous in improving the ride feeling, comfort of the occupant.

[0082] The automatic travel control section 117 generates control information for causing the vehicle 1 to travel automatically, and outputs the control information to the vehicle control device 30. The automatic travel control section 117 generates corresponding control information with respect to the parking path calculated by the parking path calculation section 115.

[0083] The storage section 120 stores a control program 121, vehicle information 122 including information related to the minimum turning radius of the vehicle 1 on which the parking assistance device 100 is mounted, and the like. The minimum turning radius is information that can determine the turning performance of the vehicle 1, and the value of the minimum turning radius itself or information that can calculate the minimum turning radius (the wheel base of the vehicle 1, the distance between the left and right steered wheels, the steering angles of the outer and inner steered wheels at the maximum steering, and the like) can be stored in the vehicle information 122.

[0084] Next, the operation of the present embodiment will be described.

[0085] During the period in which the occupant drives the vehicle 1 to move within the parking area, in the parking assistance device 100, the surrounding recognition section 111 continuously recognizes obstacles (for example, other vehicles 2, 3 shown in FIG. 6) in the surroundings on the basis of the surrounding information, and sequentially records the positions of the recognized obstacles in the map data. In addition, the parking area detection section 113 also needs to detect the parking area Q existing to the side of the vehicle 1 on the basis of the distribution of the obstacles represented by the map data or the image recognition result of the captured image. Figure 2

[0086] As shown in FIG. 7, when the occupant finds the parking area Q in front of the vehicle 1, the occupant instructs the automatic parking to the parking assistance device 100 by parking the vehicle 1 and operating an HMI (Human Machine Interface) not shown. Figure 2

[0087] The parking assistance device 100 starts the parking assistance process for causing the vehicle 1 to park into the parking area Q by automatic travel when the instruction of the automatic parking is input.

[0088] Figure 3 is a flowchart of the parking assistance process.

[0089] First, the parking assistance device 100 detects the parking area Q by the parking area detection section 113 (step S1: parking area detection step). Next, the parking assistance device 100 sets the upper limit value Ra and the lower limit value Rb of the radius of curvature R of the circular arc in the parking path on the basis of the minimum turning radius of the vehicle 1 by determining the minimum turning radius of the vehicle 1 on the basis of the vehicle information 122 by the parking path calculation section 115 (step S2: range setting step).

[0090] ​​In the present embodiment, as the upper limit value Ra of the radius of curvature R, a value obtained by multiplying the minimum turning radius by a coefficient K set in advance is set. The coefficient K takes a value that includes a range suitable for improving the ride feeling of the occupant, the comfort, and does not include an excessively large radius of curvature, for example, a value 5, or a value before and after the value 5. The coefficient K can be set to an appropriate value by the manufacturer of the vehicle 1 or the user of the vehicle 1, or the like. Thus, the upper limit value Ra of the radius of curvature R of the circular arc in the parking path can be set in correspondence with the tight turning performance of the vehicle 1.

[0091] Note that the upper limit value Ra can also be set to 50% of the maximum steering amount (also referred to as the maximum turning amount) of the vehicle 1. In this case, if the minimum turning radius is 5 m, 10 m, which is twice the value, can be set as the upper limit value Ra. The upper limit value Ra can take an appropriate value within a range in which the upper limit value Ra corresponding to the tight turning performance of the vehicle 1 can be set.

[0092] In addition, in the present embodiment, as the lower limit value Rb of the radius of curvature R of the circular arc in the parking path, the minimum turning radius of the vehicle 1 is set. Thus, a situation in which the parking path cannot be calculated to turn a full circle at the minimum turning radius of the vehicle 1 can be avoided, and the lower limit value Rb of the radius of curvature R that matches the vehicle 1 can be set. Note that the lower limit value Rb can also be set to a value greater than the minimum turning radius of the vehicle 1. The calculation of the lower limit value Rb can also take another formula that takes at least the minimum turning radius as a factor within a range in which the lower limit value Rb corresponding to the tight turning performance of the vehicle 1 can be set.

[0093] Next, the parking assistance device 100 calculates the parking path that moves the vehicle 1 from the current position to the parking area Q in such a manner that the radius of curvature R of the circular arc in the parking path is set to the upper limit value Ra by the parking path calculation section 115 (step S3) (step S4). The calculation process of the parking path can be appropriately applied to a publicly known calculation process.

[0094] Next, the parking path calculation section 115 determines whether the set radius of curvature R satisfies the lower limit value Rb (step S5), and in the case where the lower limit value Rb is not less than the lower limit value Rb (step S5; No), the radius of curvature R is changed to a value obtained by subtracting a prescribed value N from the current radius of curvature R (step S6), and the process proceeds to step S4. The prescribed value N is set to, for example, 10 cm. Note that the value N can be changed to various values.

[0095] Thus, as exemplified in Figure 4 , the parking paths of various modes in which the radius of curvature R is different are calculated. Note that in Figure 4 , the reference sign D1 indicates a position at which the forward and reverse of the vehicle 1 is switched from the current position to the position at which theFigure 4 The parking path D2 indicates a parking path from the forward-rearward switching position to the parking area Q. The radius of curvature R of the arc included in each parking path D1, D2 is set to the set radius of curvature.

[0096] In addition, reference sign C1 indicates a circle along the arc in the parking path D1, and reference sign P1 indicates the center of the circle C1. In addition, reference sign C2 indicates a circle along the arc in the parking path D2, and reference sign P2 indicates the center of the circle C2.

[0097] Figure 4 The parking paths are simply shown in the case where parking is performed from the current position to the parking area Q by one forward-rearward switching. As described above, in the case where the parking path including the arc of the set radius of curvature R cannot be calculated, the number of forward-rearward switching is changed, and the parking path including the arc of the set radius of curvature R is calculated, and thus, the parking path in which the number of forward-rearward switching is two or more can also be appropriately calculated.

[0098] Note that the parking path in which the number of forward-rearward switching is too large is not preferable, and thus, an upper limit value of the number of forward-rearward switching is set, and in the calculation process of each parking path, in the case where the parking path cannot be calculated in the range in which the number of forward-rearward switching is equal to or smaller than the upper limit value, the calculation process can also be skipped.

[0099] The steps (S3→S4→S5→S6→S4...) of calculating the parking paths of the plurality of modes in which the above-described radius of curvature R is different correspond to the parking path calculation step of the present application. In the present embodiment, the parking path is calculated until the set radius of curvature R is smaller than the minimum turning radius of the vehicle 1, and thus, the parking path including the arc of the radius of curvature R coinciding with the minimum turning radius of the vehicle 1 is also calculated.

[0100] If the parking path is calculated until the radius of curvature R is lower than the lower limit value Rb (step S5; Yes), that is, in the case where the parking path in the range in which the radius of curvature R is from the upper limit value Ra (the value K times the minimum turning radius of the vehicle 1) to the lower limit value Rb (the minimum turning radius of the vehicle 1) is calculated, the parking support device 100 shifts to the process of step S7.

[0101] In the process of step S7, the parking support device 100 selects the parking path in which the radius of curvature R of the arc is the largest from the parking paths in which the number of forward-rearward switching is the smallest among the calculated plurality of modes of parking paths by the parking path selection section 116.

[0102] Further, the parking assistance device 100 generates control information based on the selected parking path by the automatic travel control section 117, and outputs the control information to the vehicle control device 30 (step S8). Thereby, by the control of the vehicle control device 30, the vehicle 1 automatically travels from the current position and enters the parking area Q. The above step S7 corresponds to the parking path selection step of the present application, and step S8 corresponds to the automatic travel step of the present application.

[0103] Next, the comparative example and the embodiment of the present application will be described.

[0104] As shown in FIG. 10, the comparative example adopts a method of generating a parking path connecting the current position and the parking area Q by similar magnification of a basic path which is a reference of the parking path to the parking area Q. Figure 5

[0105] The basic path is a path generated using a shortest spiral curve or a circular arc calculated under a predetermined condition (for example, a prescribed vehicle speed and a rudder angle). Figure 5 In FIG. 11, a case where the embodiment of the present application is generated by a prescribed curve DC and spiral curves CL1, CL2 attached before and after the curve DC is schematically shown.

[0106] The parking path of the comparative example is generated by independently magnifying (corresponding to similar magnification) each portion DC, CL1 and CL2 of the basic path in the X direction and the Y direction in FIG. 10. Here, the curve DCa is a portion where the curve DC is similar magnified, and the spiral curves CL1a, CL2a are portions where the spiral curves CL1, CL2 are similar magnified. Since the similar magnification is performed, the radius of curvature of each portion of the parking path of the comparative example depends on the radius of curvature of each portion of the basic path and the similar magnification rate, and there is a tendency that the parking path is easily elongated as a whole. Figure 5

[0107] Figure 6 In FIG. 11, a case where the embodiment of the present application is generated by a prescribed curve DC and spiral curves CL1, CL2 attached before and after the curve DC is schematically shown.

[0108] In this Figure 6 In FIG. 11, a case where the embodiment of the present application is generated by a prescribed curve DC and spiral curves CL1, CL2 attached before and after the curve DC is schematically shown. Figure 6 In FIG. 11, a case where the embodiment of the present application is generated by a prescribed curve DC and spiral curves CL1, CL2 attached before and after the curve DC is schematically shown.

[0109] In the embodiment of the present application, among the parking paths of the plurality of patterns different in the radius of curvature R, the circular arc DCb in the parking path is set to the circular arc having the largest radius of curvature R. Thereby, as shown in FIG. 11, the parking path of the embodiment of the present application is generated. Figure 6 ​​As shown, a curvature radius greater than that of the comparative example can be obtained. Therefore, as compared with the comparative example, a parking path that is more favorable for improving the ride feeling, comfort of the occupant, and for shortening the parking time can be easily obtained.

[0110] In addition, for the clothoids CL1b, CL2b attached before and after the circular arc DCb, a curve of a short distance substantially the same as the clothoids CL1, CL2 of the basic path can also be employed, whereby a parking path that is favorable for shortening the parking time can also be obtained.

[0111] According to the present embodiment, the following effects are obtained.

[0112] The parking assistance device 100 of the present embodiment uses the minimum turning radius of the vehicle 1 determined based on the vehicle information 122 and the recognition result of the surrounding recognition section 111, and, by the parking path calculation section 115, calculates parking paths of a plurality of modes in which the curvature radius R of the circular arc included in the parking path is different, as a parking path for parking the vehicle 1 in the parking area Q. Next, the parking assistance device 100 selects, by the parking path selection section 116, a parking path with the largest curvature radius R from among the parking paths of the plurality of modes in which the number of forward-rearward switching is the least.

[0113] Thus, by selecting a parking path with the least number of forward-rearward switching (i.e., a driving operation of the vehicle 1 to change the traveling direction from forward to rearward, or from rearward to forward) and the largest curvature radius of the circular arc from among the parking paths of the plurality of modes, a parking path that is favorable for improving the ride feeling, comfort of the occupant, and for shortening the parking time can be easily determined.

[0114] Note that, while the case where the minimum turning radius of the vehicle 1 is used in the vehicle information 122 is described, the present embodiment is not limited thereto, and other information related to the parking path of the vehicle 1 can also be used. For example, as the vehicle information 122, information that enables the wheelbase of the vehicle 1 to be estimated to some extent, vehicle type information, or a pre-set evaluation value of the turning ability, or the like can also be used.

[0115] In addition, the parking assistance device 100 limits the range of the curvature radius R of the circular arc included in the parking paths of the plurality of modes by the parking path calculation section 115 based on the minimum turning radius of the vehicle 1.

[0116] Thus, a parking path including an appropriate circular arc that takes the minimum turning radius into consideration can be calculated while reducing the amount of calculation and the calculation time required for calculating the parking path.

[0117] Further, the parking assistance device 100 calculates, as the parking path of the plurality of modes, a parking path in which the radius of curvature R of the arc included in the parking path is different between the upper limit value Ra and the lower limit value Rb set based on the minimum turning radius of the vehicle 1, by the parking path calculation section 115.

[0118] Thus, it is easy to avoid a situation in which the radius of curvature R is set too large based on the minimum turning radius of the vehicle 1, or a situation in which a parking path having a sharp turn that the vehicle 1 cannot travel is set. Note that, although both the upper limit value Ra and the lower limit value Rb are set based on the minimum turning radius of the vehicle 1, only one of the values can be set as a threshold value, and the other value can be set as a fixed value set in advance.

[0119] Here, Figure 7 A flowchart of the parking assistance process of the modification example is shown. Note that the same processing as the steps shown in FIG. 8 is labeled with the same number and repeated explanations are omitted. Figure 3

[0120] The parking assistance device 100 determines the minimum turning radius of the vehicle 1 based on the vehicle information 122 by the parking path calculation section 115 after detecting the parking area Q by the parking area detection section 113 (step S1), and sets the determined minimum turning radius as the lower limit value Rb (step S2A: range setting step).

[0121] Next, the parking assistance device 100 sets the radius of curvature R of the arc in the parking path to the lower limit value Rb by the parking path calculation section 115 (step S3A), and calculates a parking path in which the vehicle 1 moves from the current position to the parking area Q to satisfy the radius of curvature R thereof (step S4).

[0122] Next, the parking assistance device 100 determines whether the number of forward-rearward switching in the parking path calculated by the parking path calculation section 115 is larger than that of the previously calculated parking path (step S5A). Here, in the case where the previous parking path is not calculated, the determination of step S5A is a negative result, the radius of curvature R is changed to a value obtained by adding a predetermined value N to the current radius of curvature R (step S6A), and the processing of step S4 is resumed.

[0123] Thus, the processing consisting of the above steps S4→S5A→S6A→S4 is repeatedly executed, and the parking paths of the plurality of modes in which the radius of curvature R is increased by the value N from the lower limit value Rb each time are calculated.

[0124] When the number of forward-rearward switching in the calculated parking path is increased compared to the previously calculated parking path (step S5A; Yes), the parking assistance device 100 resumes the processing of step S7.

[0125] ​In step S7, the parking support device 100 uses the parking path selection unit 116 to select the parking path with the largest radius of curvature R of the arc from among the parking paths calculated in multiple modes, the parking path with the fewest forward and reverse switching times. Furthermore, the parking support device 100 uses the automatic driving control unit 117 to generate control information based on the selected parking path and outputs this control information to the vehicle control device 30 (step S8).

[0126] exist Figure 7 The flowchart shown allows selection of parking paths where the radius of curvature R of the arcs included in the parking path gradually increases from the minimum rotation radius of vehicle 1. Furthermore, the calculation process for the parking path is paused when the number of forward / backward switching operations increases compared to the previously calculated parking path, and the parking path with the largest radius of curvature R of the arcs is selected from among them. This allows for the determination of a parking path with the fewest forward / backward switching operations and the largest radius of curvature R of the arcs, further reducing computational load and processing time.

[0127] In addition, if the number of forward and backward switching in the calculated parking path increases compared to the previously calculated parking path, the parking path calculation process in step S4 is terminated, so there is no need to set the upper limit value Ra of the radius of curvature R.

[0128] It should be noted that, in Figure 7 In the flowchart shown, it can also be combined with Figure 3 Similarly, in the case of the flowchart, the upper limit value Ra of the curvature radius R is set based on the minimum rotation radius, and if the curvature radius R increases compared to the upper limit value Ra, the calculation and processing of the parking path in step S4 is terminated.

[0129] In other words, if the number of forward and reverse switching in the calculated parking path increases compared to the number of forward and reverse switching in the previously calculated parking path or the predetermined number formed by the upper limit value Ra, the calculation process of the parking path in step S4 can also be terminated. The predetermined number can also be set appropriately.

[0130] It should be noted that the above embodiments are merely illustrative examples of one aspect of the present invention, and can be arbitrarily modified and applied without departing from the spirit of the present invention.

[0131] For example, in the above embodiments, it is described that the present invention is applied to... Figure 1 The parking support device 100 and its control method are shown in the illustration, but are not limited thereto. For ease of understanding of the invention, Figure 1The functional modules shown in the flowcharts shown in the drawings are schematic diagrams in which the components of the vehicle 1 and the parking assistance device 100 are classified in correspondence with the main processing contents, and the components can be classified into more components in correspondence with the processing contents. In addition, one component can be classified in such a manner as to perform more processing.

[0132] In addition, the processing of each component of the parking assistance device 100 can be performed by one hardware or can be performed using a plurality of hardware. In addition, the processing of each component can be implemented by one program or can be implemented by a plurality of programs.

[0133] In addition, Figure 3 and Figure 7 The processing units of the flowcharts shown in the drawings are portions in which the processing performed by the parking assistance device 100 is divided in correspondence with the main processing contents. The embodiments are not limited by the division method or the name of the processing units of each flowchart. In addition, the processing order of the flowcharts described above is not limited to the examples shown in the drawings.

Claims

1. A parking support device, characterized in that, include: The surrounding recognition unit identifies information about the vehicle's surroundings. The parking area detection unit uses the recognition results of the peripheral recognition unit to detect the parking area where the vehicle can park. The parking path calculation unit uses the vehicle information and the recognition result of the surrounding recognition unit to calculate a parking path with different radii of curvature of the arcs contained in the parking area, as a parking path for parking the vehicle in the parking area. as well as The parking path selection unit selects from the various parking path modes the parking path that minimizes the number of driving operations (i.e., turning around) required by the vehicle (changing direction from forward to reverse or from reverse to forward) and maximizes the radius of curvature of the arc. It has a storage unit that stores information about the vehicle, including information that can determine the vehicle's minimum turning radius. The parking path calculation unit calculates each parking path (D1, D2) by using the parking path (D1) from the current position of the vehicle to the turnaround position where the vehicle moves forward or backward, and the parking path (D2) from the turnaround position to the parking area, where the radius of the arc contained in each parking path (D1, D2) is set to the same radius of curvature. If it is impossible to calculate the parking path (D1, D2) containing the arc of the set radius of curvature, change the number of turns and calculate the parking path (D1, D2) containing the arc of the set radius of curvature. The parking path calculation unit calculates the parking paths (D1, D2) for the various modes by setting the radius of curvature to be different within a range from a lower limit to an upper limit based on the minimum rotation radius of the vehicle.

2. A control method for a parking support device, the parking support device comprising: The surrounding recognition unit identifies information about the vehicle's surroundings. The parking area detection unit uses the recognition results of the peripheral recognition unit to detect the parking area where the vehicle can park. as well as The parking path calculation unit calculates the parking path that allows the vehicle to stop in the parking area. The control method for the parking support device is characterized by performing the following steps: The parking path calculation step, which serves as the parking path, uses the vehicle information and the recognition results of the peripheral recognition unit to calculate multiple parking paths with different radii of curvature of the arcs contained in the parking path. as well as The parking path selection step involves selecting from the various parking path modes the parking path with the fewest driving operations (i.e., turning back) required for the vehicle to change direction from forward to reverse or from reverse to forward, and with the largest radius of curvature of the arc. As information about the vehicle, the control method stores information that can determine the minimum turning radius of the vehicle. In the parking path calculation step, each parking path (D1, D2) is calculated by using the radius of the arc contained in each parking path (D1, D2) from the current position of the vehicle to the turnaround position where the vehicle moves forward and backward, and the parking path (D2) from the turnaround position to the parking area, as paths with the same set radius of curvature. If it is impossible to calculate the parking path (D1, D2) containing the arc of the set radius of curvature, change the number of turns and calculate the parking path (D1, D2) containing the arc of the set radius of curvature. The parking paths (D1, D2) for the various modes are calculated so that the set radius of curvature is different within a range from the lower limit to the upper limit set based on the minimum rotation radius of the vehicle.

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