JP2014054912A - Parking support system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a parking support system which controls generating of technical hitches of parking support resulting from the incorrect detection of obstacle positions during the time of advancement when going backward of own vehicle to park at a parking space.SOLUTION: While carrying out sequential detection of obstacles which exist in back and slanting back of own vehicle by a ranging sensor prepared at the backside, a vehicle goes back. When a backward ranging means detects any obstacles near a target parking space during going backward, the position of obstacles detected, based on comparison of the position of the detected obstacle and the position of the obstacle detected by a lateral ranging means during the time of advancement, the latter is corrected. Moreover, according to the amount of correction corresponding to the corrected obstacle position, a target parking position is corrected and a parking route is re-calculated. Thus, even when the obstacle is detected in a different position from the position detected during the time of advancement, a parking route can be corrected and the parking support can be continued.

Description

  The present invention relates to a parking assistance system.

  The driver assistance system (that is, the parking assistance system) disclosed in Patent Document 1 detects the position and shape of an obstacle on the side of the vehicle by a side ultrasonic sensor group at the time of advance before parking starts. The position and shape of a parking space, which is a space where the host vehicle is to be parked, are grasped. And the parking route for parallel parking is calculated, and the own vehicle is moved along this parking route. After the vehicle enters the parking space, the lateral distance from the vehicle of the obstacle adjacent to the parking space is detected by a group of ultrasonic sensors attached to the side of the rear bumper. Comparing the shape and the shape of the parking space grasped before the start of parking, the parking route is corrected.

Special table 2011-522737

  In the technique described in Patent Document 1, the side surface of the obstacle adjacent to the parking space is detected by an ultrasonic sensor group (hereinafter referred to as a lateral distance measuring sensor) attached to the side of the rear bumper during the backward movement. By doing so, the parking route is corrected. Therefore, when the parking route is deviated so that the side distance sensor cannot detect the side surface of the obstacle on the parking space side, the parking route cannot be corrected.

  For example, if the driver greatly turns the steering wheel in the direction opposite to the side where the parking space exists during detection of the parking space during forward travel, the host vehicle moves away from the parking space. At this time, the obstacle existing on the back side in the traveling direction at the time of forward movement is likely to be out of the detection range of the ultrasonic sensor, and it becomes difficult to obtain data for detecting the position and shape of the obstacle. As a result, the parking space detection error at the time of forward movement becomes large, and a part of the area estimated as the parking space may overlap with the area where the obstacle is located.

  In such a case, there may be a case where the side surface of the obstacle on the parking space side cannot be detected and the parking route cannot be corrected based on the obstacle. And if the vehicle moves backward without correcting the parking route and approaches the obstacle until the distance to the obstacle is less than the threshold value, contact with the obstacle detected at an unexpected position is avoided. In order to do so, there was a problem that parking support was interrupted.

  The present invention has been made in view of this situation, and an object of the present invention is to provide a parking support system in which the parking support system is unlikely to be interrupted due to erroneous detection of an obstacle position.

In order to achieve the object, the present invention provides a lateral distance measuring means (1, 2) that is mounted on a vehicle and sequentially detects the distance to the obstacle based on the reflected wave of the exploration wave transmitted sequentially to the side of the vehicle. S1)
A rear ranging means (1, S101) for sequentially detecting the distance to the obstacle based on the reflected wave of the exploration wave sequentially transmitted to the rear and obliquely rear of the vehicle;
Obstacle position detecting means (1, S2) for detecting the position where the obstacle exists based on the detection result of the lateral distance measuring means when the vehicle moves forward;
A parking space detecting means (1, S3) for detecting a parking space existing on the side of the route on which the vehicle is traveling, based on the position where the obstacle detected by the obstacle position detecting means exists;
Target parking position setting means (1, S5) for setting a target parking position, which is a target position of the parking position of the vehicle, based on the parking space detected by the parking space detection means;
A parking route calculation means (1, S100, S112) for calculating a parking route for the vehicle to travel backward to the target parking position;
A support means (1) for assisting the vehicle to travel backward along the parking route calculated by the parking route calculation means, and a parking assistance device (1) comprising:
For the obstacle adjacent to the parking space, the position of the obstacle detected during forward movement is corrected based on a comparison between the position detected by the rear distance measuring means during backward movement and the position detected during forward movement. Obstacle position correcting means (1, S103, S108) to perform,
Target parking position correction means (1, S104, S111) for correcting the target parking position according to the correction amount corrected by the obstacle position correction means,
The parking route calculation means recalculates a parking route along which the vehicle travels to the target parking position based on the corrected target parking position and the current position of the vehicle.

  According to this, when the rear distance measuring means detects an obstacle adjacent to the target parking space during the backward movement, the position of the detected obstacle and the position of the obstacle detected by the side distance measuring means during the forward movement are determined. Based on the comparison, the obstacle position detected during forward movement is corrected. Then, the target parking position is corrected according to the correction amount for correcting the obstacle position, and the parking route is recalculated. For this reason, parking assistance can be continued even when an obstacle is detected at a position different from the position detected during forward movement.

It is a block diagram which shows an example of a schematic structure of a parking assistance system. It is a schematic diagram for demonstrating the outline of the parking assistance in a parking assistance system. It is a flowchart which shows an example of the flow of the parking space detection process in parking assistance ECU. It is a flowchart which shows an example of the flow of the reverse parking assistance relevant process in parking assistance ECU. It is a flowchart (continuation of FIG. 4A) which shows an example of the flow of the reverse parking assistance relevant process in parking assistance ECU. It is a schematic diagram for demonstrating the effect in this embodiment. It is a schematic diagram for demonstrating the effect in this embodiment. It is a schematic diagram for demonstrating the effect in this embodiment. It is a schematic diagram for demonstrating the effect in this embodiment.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. A parking assistance system 100 shown in FIG. 1 includes a parking assistance ECU 1, a side ranging sensor 2, a rear ranging sensor 3, a rudder angle sensor 4, a wheel speed sensor 5, a display device 6, and an audio output device 7. . Further, the parking assist ECU 1, the lateral distance measuring sensor 2, the rear distance measuring sensor 3, the rudder angle sensor 4, the wheel speed sensor 5, the display device 6, and the sound output device 7 are, for example, CAN (Controller Area Network). Each is connected via an in-vehicle LAN conforming to the communication protocol. Hereinafter, a vehicle equipped with the parking assist system 100 is referred to as a host vehicle.

  The lateral distance measuring sensor 2 and the rear distance measuring sensor 3 are sensors used to detect a distance to an obstacle by transmitting a survey wave and receiving a reflected wave of the survey wave reflected by the obstacle. It is. In the present embodiment, a distance measuring sensor that transmits ultrasonic waves as an exploration wave, that is, an ultrasonic sensor is used. Examples of other distance measuring sensors include laser radar and millimeter wave radar.

  The lateral distance measuring sensors 2 are arranged one by one on the left and right side surfaces of the front bumper of the own vehicle, for example, so that the directivity center line is parallel to the axle direction of the own vehicle. The directivity center line of the lateral distance measuring sensor 2 may be arranged to be inclined, for example, to about 20 ° from the axle direction of the own vehicle. Further, the directivity of the lateral distance measuring sensor 2 is preferably narrower as long as it is wide enough to perform transmission / reception in use in the assumed vehicle speed range. Hereinafter, the side ranging sensor 2 on the left side of the host vehicle is referred to as a side ranging sensor 2a, and the side ranging sensor 2 on the right side of the host vehicle is referred to as a side ranging sensor 2b.

  A total of four rear ranging sensors 3 are arranged, for example, one at the left and right corners of the rear bumper of the own vehicle and one at the left and right near the center of the rear bumper. These four rear ranging sensors 3 detect obstacles within a predetermined range obliquely rearward and rearward (for example, the maximum detection distance is about 1.5 m). Thereafter, the rear ranging sensor 3 provided at the rear left corner of the host vehicle is the rear ranging sensor 3a, the rear ranging sensor 3 at the left rear center of the host vehicle is the rear ranging sensor 3b, and the rear rear center sensor is at the rear right center. The distance measuring sensor 3 is referred to as a rear distance measuring sensor 3c, and the rear distance measuring sensor 3 provided at the rear right corner of the host vehicle is referred to as a rear distance measuring sensor 3d.

  In the present embodiment, for the sake of explanation, the rear distance measuring sensors 3a to 3d all form the same detection range, but the present invention is not limited to this. The maximum detection distance of the rear ranging sensors 3b and 3c installed near the center may be larger than the detection distance of the rear ranging sensors 3a and 3d installed in the corner portion. Further, the number of the rear ranging sensors 3 is not limited to four. What is necessary is just to be able to detect an obstacle existing diagonally behind and behind the vehicle.

  The rudder angle sensor 4 is a sensor that detects the steering angle of the steering of the host vehicle. The steering angle when the host vehicle travels in a straight traveling state is set to the neutral position (0 degree), and the rotation angle from the neutral position is steered. Output as a corner. The steering angle is output with a positive (+) sign when rotating right from the neutral position, and is output with a negative (-) sign when rotating left from the neutral position. The The wheel speed sensor 5 is a sensor that detects the speed of the vehicle from the rotational speed of each wheel.

  The display device 6 displays text and images in accordance with instructions from the parking assistance ECU 1. For example, the display device 6 is capable of full color display and can be configured using a liquid crystal display, an organic EL display, a plasma display, or the like. The display device 6 may be configured to use a display provided in the in-vehicle navigation device, or may be configured to use a display provided in an instrument panel or the like separately from the display of the in-vehicle navigation device. Good.

  The audio output device 7 is constituted by a speaker or the like, and outputs audio according to an instruction from the parking assistance ECU 1. In addition, as the audio | voice output apparatus 7, it is good also as a structure which utilizes the audio | voice output apparatus provided in the vehicle-mounted navigation apparatus, for example.

  The parking assist ECU 1 is mainly composed of a microcomputer, and each includes a well-known CPU, a memory such as a ROM, a RAM, and an EEPROM, an I / O, and a bus connecting them. The parking assist ECU 1 executes various control programs stored in the ROM based on various information input from the lateral distance measuring sensor 2, the rear distance measuring sensor 3, the steering angle sensor 4, and the wheel speed sensor 5. Various processes such as a process related to parking support for reversing the host vehicle and parking in parallel in the parking space (hereinafter referred to as parking support process) are executed. The parking assistance ECU 1 corresponds to the parking assistance device in the claims.

  First, with reference to FIG. 2 and FIG. 3, a description will be given of the process until the host vehicle A reaches the reverse start position P5. FIG. 2 is a schematic diagram for explaining the outline of the parking support process in the parking support system 100. Here, for convenience, a plurality of parked vehicles (B1, B2, B3) and parking spaces (C1, C2) are alternately arranged on the left side of the host vehicle, and the driver of the host vehicle parks the front side in the traveling direction when moving forward. The case where the target parking position is set in the space C2 will be described as an example.

  In FIG. 2, A indicates the own vehicle, the arrow indicated by a solid line indicates the route when the own vehicle moves forward, and the arrow indicated by a broken line indicates the route when the own vehicle moves backward. B1, B2, and B3 are parked vehicles that are parked in parallel, and the vehicle passes through these sides in the order of parked vehicles B1, B2, and B3 when moving forward. Here, the traveling direction when the vehicle moves forward, that is, the direction in which the parked vehicles B1 to B3 are parked in parallel is hereinafter referred to as a lateral direction. In a plane parallel to the road surface, a direction perpendicular to the lateral direction is defined as a y direction, a direction entering the parking space from the passage in the y direction is defined as a positive y direction, and a reverse direction is defined as a negative y direction. Further, a lateral distance between spaces between obstacles where no obstacle is detected is defined as a parking space width D. Here, for the sake of convenience, the side distance measuring sensor 2a disposed on the left side surface of the vehicle A and the detection range E formed by the exploration wave transmitted by the side distance measuring sensor 2a will be illustrated and described.

  The own vehicle A passes the side of the parked vehicles B1 and B2 while sequentially transmitting the exploration wave from the side ranging sensor 2a toward the left side of the own vehicle A (for example, every 100 msec). The detection start condition by the side distance measuring sensor 2 may be set when the vehicle speed of the host vehicle A becomes a predetermined speed (for example, 15 km / h) or less. The parking assist ECU 1 measures the distance to the obstacle from the time taken until the side ranging sensor 2 transmits the exploration wave and receives the reflected wave. Further, since the lateral distance measuring sensor also moves as the vehicle moves, the position of the obstacle can be detected by a known triangulation technique using this moving distance.

  Then, the contour shape of the parked vehicle B1 or the parked vehicle B2 or B1 is specified from the distance data series (point sequence) in which the distance to the obstacle is stored in time series by sequentially receiving the reflected wave from each parked vehicle. The parking space C1 is detected. These correspond to steps S1 to S3 in FIG.

  As an example, the contour shape of the parked vehicles B1 and B2 is obtained by approximating a distance data series (dot sequence) by an ellipse or a parabola by a known method similar to that disclosed in Japanese Patent Application Laid-Open No. 2008-21039. It specifies (FIG. 3 S1). In the parked vehicle end detection process (S2), the positions of the vehicle ends facing each other in the lateral direction of the parked vehicles B1 and B2 are determined. And the distance (namely, parking space width D) between this vehicle end is calculated | required (S3). For example, the left side edge of the parked vehicle B1 is detected at P1, and the right side edge of the parked vehicle B2 is detected at P2 (S2). Thereby, the width (hereinafter referred to as parking space width) D1 of the parking space C1 is obtained (S3).

  Here, the configuration in which the positions of the vehicle ends of the parked vehicles B1 and B2 are both determined from the contour shapes of the parked vehicles B1 and B2 is shown, but the configuration is not necessarily limited thereto. For example, the vehicle end of the parked vehicle B is determined from the contour shape of the parked vehicle B1, and the vehicle end of the parked vehicle B2 is a point at a certain distance from the vehicle end of the parked vehicle B1 in the traveling direction of the own vehicle A. It is good also as composition to do. The fixed distance here is a value of a minimum opening width (hereinafter referred to as an accessible width) required as a parking space for parallel parking of the own vehicle A, and is set according to the width of the own vehicle A. The As an example, in this embodiment, the allowable width is set to a vehicle width +0.8 m obtained by adding 0.4 m to the left and right of the own vehicle.

  By using this vehicle end determination method, not only the parking space for one vehicle sandwiched between two parked vehicles is detected, but also the parking space for one vehicle is sandwiched between two parked vehicles. It is good also as a structure which detects the parking space which is not (that is, adjoining only one parked vehicle).

  The boundary line between the parking space and the passage may be aligned with the passage-side end surface of the parked vehicle adjacent to the parking space. In addition, when both sides of an obstacle adjacent to the parking space are detected, it may be adjusted to the end face on the aisle side of one of the parked vehicles, or at an intermediate position between the end faces on the aisle side of the parked vehicles on both sides. You may combine them.

  In addition, although the method for detecting the parking space C1 from the contour shape of the parked vehicles B1 and B2 (or either one) has been described above for explanation, the same applies from the contour shape of the parked vehicles B2 and B3 in the parking space C2. Can be requested.

  Thereafter, it is determined whether the detected parking space C2 is set as a parking space in which the vehicle A is parked (S4). Here, in order to distinguish from other parking spaces (for example, C1), a parking space in which the host vehicle A is to be parked is defined as a target parking space. For example, when a parking preliminary operation such as turning the steering wheel within a predetermined range (for example, several meters) from the position where the parking space is detected is detected, S4 becomes Yes, and this parking space is set as the target parking space. The target parking position is arranged at the center of the target parking space (S5). On the other hand, if the predetermined distance from the parking space C2 is detected without detecting the parking preliminary operation, S4 is No, the parking space position is stored in the memory provided in the parking assist ECU 1 (S6), and the parked vehicle detection process ( Return to S1).

  The position of the vehicle end may be expressed as coordinates in the ground surface coordinate system that is a coordinate system on the road surface. The origin of the ground surface coordinate system is, for example, the position of the center of the rear axle of the own vehicle A at the start of detection by the side distance measuring sensor 2. The horizontal axis (x axis) constituting the coordinate system may be parallel to the above-described horizontal direction, and the vertical axis (y axis) may be parallel to the y direction. In addition, what is necessary is just to set it as the structure determined by calculating the variation | change_quantity from an origin based on the steering angle and vehicle speed which are obtained sequentially from the steering angle sensor 4 and the wheel speed sensor 5 about the own vehicle position after a movement. .

  The host vehicle advances while sequentially detecting surrounding obstacle shapes, and parking assist processing at the time of reverse starts from the reverse start position P5 at which the shift position of the own vehicle A becomes the R position. Here, when the error between the obstacle position detected at the time of forward movement and the actual obstacle position is small, there is a low possibility of contact with the obstacle in the process of retreating the vehicle along the parking route. Parking support processing is rarely interrupted. And if the own vehicle can move to a place where an obstacle adjacent to the target parking space C2 can be detected by the side ranging sensor 2, the parking route can be corrected by the technique described in the prior document 1, for example. .

  However, if the driver greatly turns the steering wheel while the parking space is being detected during forward movement (for example, during movement from P3 to P4), the vehicle is an obstacle positioned forward in the traveling direction when viewed from the vehicle (in this case, the parked vehicle B3). ) And turn away sharply. In such a case, the reflected wave returning from the obstacle located in the front side of the traveling direction, that is, the number of data for calculating the obstacle position decreases, so the obstacle position calculated by the parking assistance ECU 1 There is a possibility that an error generated between the actual obstacle position and the actual obstacle position becomes large. In the parking route based on the position information of obstacles including a large error, the vehicle may move so as to touch the neighboring obstacles, and if the vehicle is too close to the obstacles, the vehicle is obstructed. The retreat is stopped to avoid touching the object. However, in the parking assistance system 100 of the present embodiment, initially, even if a parking route that contacts an adjacent obstacle is calculated, the parking route is corrected during the backward movement by executing the process shown in FIG. The parking assistance control is less likely to be interrupted.

  The operation of the parking assistance ECU 1 during backward parking assistance will be described using the flowcharts of FIGS. 4A and 4B. The process shown in the flowchart of FIG. 4A is started when the parking assist ECU 1 detects a predetermined start trigger. As the start trigger, for example, when a reverse start position is reached and a shift lever (not shown) of the host vehicle A is set to the reverse position, the start trigger can be cited.

  In step S100, a route from the current own vehicle position, the current direction of the own vehicle with respect to the target parking position, and the target parking position to the target parking position (hereinafter, parking route) is calculated. Thereafter, when the driver starts moving the vehicle by weakening the depression of the brake pedal, automatic steering control is started so that the vehicle automatically moves along the parking route. Here, although the driver performs speed control by operating a brake pedal (not shown), the speed may be automatically controlled.

  In step S101, an exploration wave is transmitted from the rear ranging sensor 3 during retreat, and the presence or absence of obstacle detection is determined. Note that the processing of FIGS. 4A and 4B is repeated periodically, and therefore step S101 is also sequentially executed. The execution cycle of step S101 is, for example, every 100 msec. In addition, the vehicle position, the position of the obstacle detected when moving forward, the target parking position, etc. are grasped in the ground surface coordinate system, and the moving vehicle position is obtained sequentially from the rudder angle sensor 4 and the wheel speed sensor 5. It is calculated based on the steering angle and the vehicle speed.

  If the rear distance measuring sensor 3 has not detected an obstacle, step S101 is No, and the vehicle continues to reverse in accordance with the automatic steering control of the parking assist ECU 1. On the other hand, if any obstacle is detected by any one of the rear ranging sensors 3 (3a to 3d) during the backward movement, Step S101 is Yes and the process proceeds to Step S102.

  In step S102, the area where the detected rear ranging sensor 3 transmits the exploration wave is calculated from the current vehicle position and the vehicle direction in the ground surface coordinate system, and the obstacle detected in step S101 is the target. It is determined whether the obstacle is located on the left or right side of the parking space. When it is determined that the detected obstacle on one side or both sides is an obstacle located on one of the left and right sides of the target parking space, the process proceeds to step S103. Of the obstacles adjacent to the target parking space, when this step 102 is Yes, the side where the detected obstacle exists is the detection side, and the side not detected is the undetected side.

  On the other hand, if a plurality of obstacles are detected in step S102 and it is determined that these are obstacles located on both sides of the target parking space, the process proceeds to step S108.

  In step S103, the obstacle position on the detection side is corrected (translated in the lateral direction and the y direction). The amount to be corrected (correction amount) may be an amount that is deviated by comparing the obstacle position detected during the backward movement with the obstacle position detected during the forward movement. The obstacle position to be detected at the time of backward movement is the same as the obstacle detection at the time of forward movement. A distance data series (point sequence) in which distances to obstacles at multiple measurement points are stored in time series is generated and detected obstacles. A region where an obstacle exists is obtained from the contour shape of the object.

  In step S104, the position of the target parking space and the target parking position are corrected by the correction amount obtained by correcting the obstacle on the detection side in step S103. For example, if the obstacle on the detection side is translated 0.1 m to the right in the lateral direction, the position of the target parking space and the target parking position are also translated 0.1 m to the right in the lateral direction. When correction based on the position of the obstacle on the detection side is performed, the fact that it has been corrected is held as an internal state, and if it has already been corrected, correction processing (steps S103 to S104) is performed again. You may make it not.

  In addition, the obstacle-free judgment line (line segment) for judging that there is no obstacle at the time of reversing when entering 0.1 m in the positive y direction from the boundary line on the passage side of the corrected target parking space. ) Set L. The position where the obstacle absence determination line is set is not limited to the position 0.1 m in the positive y direction from the side surface on the aisle side of the target parking space. Of the end points of the obstacle absence determination line, the end point on the detection side is defined as an obstacle side end e.

  In step S105, the parking assistance ECU 1 determines whether the detectable range of the rear distance measuring sensor 3 extends to the obstacle absence determination line from the own vehicle position and the obstacle detectable range of the rear distance measuring sensor 3. To do. Here, the detectable range is a range formed by the detection maximum distance of the exploration wave transmitted by the rear ranging sensor 3, but is not limited thereto. The detectable range may be a range formed by a distance obtained by multiplying the maximum reachable distance of the exploration wave by a predetermined safety factor (for example, 0.8). If the detectable range of the rear ranging sensor 3 has reached the obstacle-free determination line, step S105 is Yes and the process proceeds to step S106. If the detectable range of the rear ranging sensor 3 has not reached the obstacle-free determination line, step S105 returns No and returns to step S100, and the target parking position corrected in step S104 from the current own vehicle position. Recalculate the parking route until and continue the parking assistance process.

  In step S106, the temporary parking space is recognized. As for the position in the width direction (lateral direction) of this temporary parking space, one end is set as the above-mentioned obstacle side end e1. The other end is a point (detected end e2) farthest from the obstacle side end e1 in a portion where the obstacle absence determination line and the obstacle detectable range overlap. That is, this temporary parking space represents a space that is determined to have no obstacle even when retreating. When at least one of the obstacle-side end e1 and the detected end e2 is updated, the width of the temporary parking space (temporary parking space width D ') is also updated.

  In step S107, the temporary parking space width D 'is compared with the accessible width. If it is determined that the temporary parking space width D ′ is equal to or greater than the allowable entry width (S107 Yes), the temporary parking space is set as the target parking space, and the process proceeds to step S111. If it is determined that the temporary parking space width D ′ is smaller than the allowable entry width, the process returns to step S100 to recalculate the parking route from the current own vehicle position to the target parking position corrected in step S104, and park the vehicle. Continue the support process.

  Step S108 is processing when it is determined in step S102 that both obstacles located on both sides of the target parking space are detected. Here, in the obstacles positioned on both sides of the target parking space, the obstacle position is corrected from the detected obstacle detection data, as in step S103.

  In step S109, the target parking space is corrected and the parking space width D is recalculated using the corrected obstacle position. In step S110, the parking assistance ECU 1 compares the recalculated parking space width D with the allowable width, and determines whether the host vehicle is allowed to enter. If the parking assist ECU 1 determines that parking is possible, the result of step S110 is Yes, and the process proceeds to step S111. On the other hand, if the parking assist ECU 1 determines that parking is not possible in step S110, S110 is No and the process proceeds to step S113.

  In step S111, the target parking position is set at the center of the target parking space, and the process proceeds to step S112.

  In step S112, a parking route from the current vehicle position to the corrected target parking position is calculated. Then, in the process of traveling along the parking route, if the side surface of the target parking space side of the obstacle adjacent to the target parking space can be detected by the side ranging sensor 2 of the own vehicle, What is necessary is just to further correct | amend a target parking position and a route with the technique of the prior art document 1.

  In step S113, it is determined whether or not there is another parking space within a range that can be guided from the current vehicle position (for example, within a range of 10 m). This is because when a plurality of parking spaces can be detected when the host vehicle A moves forward, these positions are stored in S6 of FIG. The parking space to be memorized may be preferentially memorized in several places from the one close to the own vehicle position, or all the parking spaces existing within a certain distance from the current position may be memorized. Good. If another parking space exists at a distance that can be guided from the current position, Step S113 becomes Yes, and the process proceeds to Step S114. If there are a plurality of candidate parking spaces, the positions may be displayed on the display device 6 and selected by the user.

  In step S114, the parking space selected in step S113 is set as a new target parking space, and the process proceeds to step 115.

  In step S115, the target parking position is arranged at the center of the target parking space, the process returns to step S100, the parking route from the current vehicle position to the target parking position is recalculated, and the parking support process is continued.

If it is determined in step S113 that no other parking space exists at a distance that can be guided from the current position, the process proceeds to step S116, and parking assistance is interrupted.
An example in which the above processing is applied to the backward movement from the backward movement start position P5 in FIG. 2 will be described with reference to FIG. FIG. 5 shows a situation in which an obstacle is detected by the rear distance measuring sensor 3a when the vehicle automatically moves backward by the parking assistance process (S101 Yes). At this time, the exploration wave of the rear ranging sensor 3a is transmitted in the direction of the left side of the target parking space C2, that is, the direction of the parked vehicle B3. Therefore, the parking assist ECU 1 determines that the obstacle detected by the rear distance measuring sensor 3a is an obstacle corresponding to the parked vehicle B3. The other rear ranging sensors 3b to 3d do not detect other obstacles. From the above, the parking assist ECU 1 determines that an obstacle has been detected only on one side (left side) of the target parking space C2 (No in S102). Here, the left side of the target parking space C2 is the detection side, and the right side of the target parking space C2 is the undetected side here.

  The parking assist ECU 1 compares the position of the parked vehicle B3 detected when moving forward with the position of the obstacle detected by the rear distance measuring sensor 3a when moving backward, and corrects the position of the parked vehicle B3 to B3a (S103). Then, the target parking space C2 and the target parking position P10 are corrected by the amount obtained by correcting the position of the obstacle on the detection side, and are set as the target parking space C2a and the target parking position P10a, respectively (S104). In FIG. 5, since the detectable range of the rear ranging sensor 3 has not reached the obstacle determination line L (No in S105), the process returns to S100 and continues to move backward.

  After that, FIG. 6 shows a schematic diagram of a state in which the reversible is continued and the detectable range reaches the obstacle absence determination line L. Here, for simplicity of explanation, the parked vehicle B2 and the like are omitted. In FIG. 6, the temporary parking space width D ′ is from the obstacle side end e to the detected end e ′ where the detectable range overlaps the obstacle absence determination line (S <b> 106). Then, the temporary parking space D ′ is compared with the allowable width, and when it is determined that the temporary parking space width is larger than the allowable width (S107 Yes), the target parking position is set at the center of the temporary parking space. (S111). Then, the parking route is recalculated and the parking assistance is continued (S112).

  Thereafter, the parking position may be further corrected using a conventional technique as long as the side ranging sensor 2 can detect the side surface of the adjacent vehicle so long as the vehicle can enter the parking space.

  FIG. 7 shows a case where the rear ranging sensor 3 detects an obstacle (here, a parked vehicle) on both sides of the target parking space C2 (Yes in S102). At this time, the position of the parked vehicle B3 is corrected to B3a and the position of the parked vehicle B2 is corrected to B2a from the information of the obstacle position detected at the time of forward travel and the information of the obstacle position detected by the rear distance measuring sensor 3 at the time of backward travel. (S108). From the corrected positions of the parked vehicle B3a and the parked vehicle B2a, the target parking space is corrected to C2b, and the parking space width D3 is calculated (S109). And parking assistance ECU1 compares this recalculated parking space width D3 with the approachable width, and if the parking space width D3 is larger (S110 Yes), it determines that it can enter, and progresses to S111, Continue parking assistance as described above.

  Further, when it is determined that entry is impossible from the recalculated parking space width D3 and the accessible width (No in S110), it is determined whether another parking space (here, the parking space C1) exists (S113). . Here, when another parking space (here, the parking space C1) exists (S113 Yes), as shown in FIG. 8, from the current position toward the target parking position P10b set to the new target parking space C1. The parking assistance is continued (return to S100). In addition, the broken line arrow of FIG. 8 represents the parking route from the current position to the target parking position P10b, which is recalculated after returning to S100.

  According to such a configuration, even if the obstacle position detected at the time of forward movement has an error from the actual obstacle position, the parking path can be determined by correcting the target parking position according to the correction amount of the obstacle position. You can recalculate and continue parking assistance.

  In the present embodiment, the parking space width of the target parking space is calculated when both obstacles located on both sides of the target parking space are detected. However, the present invention is not limited to this. For example, as shown in P3 of FIG. 2, since the own vehicle A travels in the vicinity of the parked vehicle B2 located behind the forward travel direction, the detection accuracy of the obstacle position of the parked vehicle B2 is the front side in the travel direction. It can be expected to be higher than the parked vehicle B3. For this reason, when it is possible to determine that the detection accuracy when detecting the rear parked vehicle at the time of forward movement is good even in the situation where only the parked vehicle in the forward direction of the target parking space can be detected at the time of reverse movement, The parking space width may be calculated by using the rear obstacle position as the position detected during forward movement. Regarding the determination of the detection accuracy, for example, when the curvature of the vehicle traveling locus during obstacle detection is a predetermined value or less, or in the distance data series (point sequence) for detecting the contour of the obstacle, the interval between the points is When it is below the predetermined value, it is determined that the detection accuracy is good.

  Further, in the above-described embodiment, the obstacle position correction process is performed by a parallel movement combining the horizontal direction and the y direction, but it may be a parallel movement of at least one of the horizontal direction and the y direction.

A ... own car, B1, B2, B2a, B3, B3a ... parked vehicle,
C1, C1a, C2 ... parking space, P10, P10a, P10b ... target parking position,
DESCRIPTION OF SYMBOLS 1 ... Parking assistance ECU, 2 ... Side distance sensor, 3 ... Back distance sensor

Claims (5)

Mounted on the vehicle,
Side ranging means (1, S1) for sequentially detecting the distance to the obstacle based on the reflected wave of the exploration wave sequentially transmitted to the side of the vehicle;
A rear ranging means (1, S101) for sequentially detecting the distance to the obstacle based on the reflected wave of the exploration wave sequentially transmitted to the rear and obliquely rear of the vehicle;
Obstacle position detecting means (1, S2) for detecting the position where the obstacle exists based on the detection result of the lateral distance measuring means when the vehicle moves forward;
A parking space detecting means (1, S3) for detecting a parking space existing on the side of the route on which the vehicle is traveling, based on the position where the obstacle detected by the obstacle position detecting means exists;
Target parking position setting means (1, S5) for setting a target parking position, which is a target position of the parking position of the vehicle, based on the parking space detected by the parking space detection means;
A parking route calculation means (1, S100, S112) for calculating a parking route for the vehicle to travel backward to the target parking position;
A support means (1) for assisting the vehicle to travel backward along the parking route calculated by the parking route calculation means, and a parking assistance device (1) comprising:
For the obstacle adjacent to the parking space, the position of the obstacle detected during forward movement is corrected based on a comparison between the position detected by the rear distance measuring means during backward movement and the position detected during forward movement. Obstacle position correcting means (1, S103, S108) to perform,
Target parking position correction means (1, S104, S111) for correcting the target parking position according to the correction amount corrected by the obstacle position correction means,
The parking route calculating device recalculates a parking route along which the vehicle travels to the target parking position based on the corrected target parking position and the current position of the vehicle. The parking assist device according to claim 1,
When the obstacle on both sides of the parking space can be detected by the rear distance measuring means while the vehicle is moving backward, the parking space is detected based on the position of the obstacle corrected by the obstacle position correcting means. Parking space width correction means (1, S109) for correcting the length in the width direction;
1st entry possibility judgment means (1, S110) which judges whether the own vehicle can enter into the parking space based on the width direction length of the parking space corrected by the parking space width correction means. A parking assist device. The parking assistance device according to claim 1 or 2,
When an obstacle on one side of the parking space is detected by the rear distance measuring means while the vehicle is moving backward, an obstacle is detected in the parking space based on the detection result of the rear distance measuring means. Parking space width update means (1, S106) for sequentially updating the width direction length of the space confirmed not to exist,
By sequentially comparing the width direction length sequentially updated by the parking space width updating means and the preset allowable width, based on the fact that the width direction length is equal to or greater than the allowable width, A parking assistance device comprising: a second approachability determining means (1, S107) that determines that the own vehicle can enter the parking space. In claim 2,
The position acquired when the vehicle is moving forward when the obstacle on one side of the parking space is detected by the rear distance measuring means while the vehicle is moving backward, and the obstacle on the other side of the parking space is detected. If it can be determined that the detection accuracy of the parking space is good, the parking space width correction means uses the position detected during advance as the position of the obstacle on the other side adjacent to the parking space, and uses the width direction of the parking space. A parking assistance device that corrects a length. In any one of Claims 2-4,
When a plurality of parking spaces are detected by the parking space detection means, among the plurality of parking spaces, a plurality of parking spaces excluding the parking space where the target parking position is set by the target parking position setting means are parked. Storage processing means (1, S6) to be stored in a predetermined storage unit as a space candidate;
Whether or not the parking space candidate exists within a distance range that can be guided from the current position of the vehicle when it is determined by the entry possibility determination means (1, S110) that the vehicle cannot enter the parking space. A parking space candidate determination means (1, S113) for determining a parking space candidate stored in the storage unit,
Parking space changing means (1, S114) for changing the parking space for resetting the target parking to the parking space candidate when the parking space candidate determining means determines that the parking space candidate exists. Prepared,
The target parking position setting means (1, S115) resets the target parking position based on the parking space changed by the parking space changing means,
The parking route calculation means recalculates a parking route on which the vehicle travels to the target parking position based on the target parking position reset by the target parking position setting means and the current position of the vehicle. A parking assist device.

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